Vascular Surgery in Japan: 2019 Annual Report by the Japanese Society for Vascular Surgery

Abstract

Objectives: This is an annual report indicating the number and early clinical results of annual vascular treatment performed by vascular surgeons in Japan in 2019, as analyzed by database management committee (DBC) members of the JSVS.

Materials and Methods: To survey the current status of vascular treatments performed by vascular surgeons in Japan, the DBC members of the JSVS analyzed the vascular treatment data provided by the National Clinical Database (NCD), including the number of treatments and early results such as operative and hospital mortality.

Results: In total 154,460 vascular treatments were registered by 1,082 institutions in 2019. This database is composed of 7 fields including treatment of aneurysms, chronic arterial occlusive disease, acute arterial occlusive disease, vascular injury, complication of previous vascular reconstruction, venous diseases, and other vascular treatments. The number of vascular treatments in each field was 23,826, 17,100, 4,947, 2,369, 674, 54,023, and 51,521, respectively. In the field of aneurysm treatment, 20,369 cases of abdominal aortic aneurysm (AAA) including common iliac aneurysm were registered, and 63.3% were treated by endovascular aneurysm repair (EVAR). Among AAA cases, 1,739 (8.5%) cases were registered as ruptured AAA. The operative mortality rates of ruptured and un-ruptured AAA were 15.0%, and 0.6%, respectively. 43.8% of ruptured AAA were treated by EVAR, and the EVAR ratio was gradually increasing, but the operative mortality rates of open repair and EVAR for ruptured AAA were 12.6%, and 15.4%, respectively. Regarding chronic arterial occlusive disease, open repair was performed in 8,026 cases, including 1,250 distal bypasses to the crural or pedal artery, whereas endovascular treatment (EVT) was performed in 8,879 cases. The EVT ratio was gradually increased at 51.9%. Varicose vein treatment was decreased in 42,313 cases (1.9% less than in 2018), and 79.8% of the cases were treated by endovenous thermal ablation (ETA) including endovenous laser ablation (EVLA) and radio-frequency ablation (RFA). Regarding other vascular operations, 47,605 cases of vascular access operations and 1,703 lower limb amputation surgeries were included.

Conclusions: The number of vascular treatments increased since 2011, and the proportion of endovascular procedures increased in almost all fields of vascular diseases, especially EVAR for AAA, EVT for chronic arterial occlusive disease, and ETA for varicose veins. (This is a translation of Jpn J Vasc Surg 2024; 33: 307–335.)

Introduction

Following the launch of the National Clinical Database (NCD) and initiation of surgical case registration in 2011, the Japanese Society for Vascular Surgery has been compiling vascular surgery cases from NCD-registered cases and publishing an annual report on vascular surgery as an academic meeting.^1–14) This paper presents the results of the vascular surgery cases registered in NCD from January 2019 to December 2019, which were tabulated and analyzed by the members of the Database Management and Steering Committee of the Japanese Society for Vascular Surgery.

Methods

The vascular surgery data extracted from the surgical procedures registered with NCD in 2019, at the request of the Japanese Society for Vascular Surgery (member society of NCD), were classified into the following 7 categories: (1) revascularization for aneurysms, (2) revascularization for chronic arterial occlusive disease, (3) revascularization for acute arterial occlusive disease, (4) treatment of vascular trauma, (5) surgery for complications of revascularization, (6) venous surgery, and (7) other vascular diseases and related surgeries. Tabulated data were reviewed by members of the Japanese Society for Vascular Surgery Database Management Steering Committee, and tabulated results were analyzed.

The compiled results included the number of surgical procedures performed, etiology of conditions treated, number of operative and in-hospital deaths, and materials used. Operative death, synonymous with surgical death, refers to any death that occurs within 30 days following surgery, irrespective of the cause or patient’s hospitalization status. In-hospital deaths are defined as those occurring during the period of continuous hospitalization after surgery, regardless of the duration of the stay.

For data on etiology and materials used, there were some discrepancies in the values presented in tables, such as the data sum was inconsistent with the total number of cases. After careful investigation by the Committee and NCD, it was concluded that the discrepancies were due to one of the following 5 reasons: (1) selection of multiple choices was permitted, (2) blank choices were permitted, (3) omissions or incorrect entries made by the data entry person, (4) use of multiple materials in a single procedure or treatment involving multiple sites, and (5) inadequate item expansion conditions. Since 2013, we have implemented measures to viably minimize input errors. These measures include reorganizing existing options, introducing new ones, and programming the system to prevent the registration of incomplete items for fields where leaving them blank would make registration impossible.

Table 1 shows the items for which the registration and tabulation methods have changed since 2017.

Table 1 Major changes in the 2019 annual report.

Item	Change details
Thoracic aortic aneurysm (ascending, arch, descending)	Unified registration with JCVSD
Thoracoabdominal aortic aneurysm	If "Thoracoabdominal" is selected under "Site of aortic aneurysm," the thoracoabdominal registry will be shown
Arterial occlusive diseases	The input was to be made for both sides or for each of the left and right sides
Venous surgery	The input was to be made for both sides or for each of the left and right sides

Tabulation and Analysis Results

The total number of vascular surgeries registered with NCD in 2019 was 154,460 (a 7.5% increase from the previous year), accounting for 9.9% of the total number of surgical procedures (1,558,465) registered with NCD in the same year (9.4% in the previous year). Moreover, 1,082 institutions registered vascular surgery, which represented 28.1% of the 3,854 institutions registering surgeries. Of these 1,082 institutions, 517 (46.8%) were certified cardiovascular surgery training facilities (as of 2019). However, the total number of certified cardiovascular surgery training facilities was 544, and 95% (517/544) of these institutions registered data for vascular surgery. The tabulated and analytical results for 2019 are explained below by category.

1. Treatment for Aneurysms (Tables 2-1 and 2-2)

Table 2 Treatment for aneurysm: Table 2-1 Aortic aneurysm.

Region of aortic aneurysm	Cases	Gender		Mortality		Ruptured aneurysm			Dissectionc	Etiology
		Male	Female	30-day death	In-hospital death	Cases	30-day death	In-hospital death		Degeneratived			Inflammatory	Vasculitis	Infected	Connective tissue diseasee	Others
										Cases	30-day death	In-hospital death
Thoracoabdominal aortaa	177	137	40	9	11	21	5	7	51	160	9	10	1	0	5	2	9
Abdominal aortic aneurysmb	20,369	16,813	3,556	370	487	1,739	261	327	928	19,621	345	436	213	12	255	31	237
With renal artery reconstruction	372	306	66	9	16	31	4	9	33	358	9	15	3	0	5	1	5
With renal artery clamping	1,439	1,221	218	51	72	192	33	44	82	1,356	45	61	36	0	29	4	14
With internal iliac artery aneurysm	879	771	108	20	23	85	13	13	48	847	19	22	8	1	15	1	7
With internal iliac artery reconstruction	1,360	1,214	146	13	17	78	9	9	91	1,312	12	16	13	0	11	9	15
Simultaneous thoracic aortic surgery	178	136	42	15	18	18	8	9	50	162	15	18	2	1	1	2	10

Table 2-1 Aortic aneurysm (continued).

Region of aortic aneurysm	Treatment procedure						Graft materialsg
	Replacement			Exclusion with bypass	Stent graft	Hybridf	Polyester	ePTFE	Others
	Cases	Bifurcated-graft	Straight-graft
Thoracoabdominal aortaa	4	3	0	1	115	6	47	8	0
Abdominal aortic aneurysmb	6,936	5,577	992	38	12,846	47	6,566	433	60
With renal artery reconstruction	342	265	54	5	12	4	326	30	6
With renal artery clamping	1,416	1,124	243	2	7	4	1,329	91	10
With internal iliac artery aneurysm	786	623	36	2	17	13	730	57	8
With internal iliac artery reconstruction	1,303	999	54	3	23	20	1,231	79	20
Simultaneous thoracic aortic surgery	11	9	0	5	112	2	34	13	3

a: These data are not including cases recorded in JCVSD Database in which most cardiac surgeons were entering their cases.

b: Including common iliac artery aneurysm.

c: Including both acute and chronic aortic dissection.

d: Most likely atherosclerosis.

e: Connective tissue abnormalities such as Marfan syndrome.

f: Debranch bypass surgery combined with two staged TEVAR is counted as one case of hybrid treatment.

g: Only for open surgery.

Table 2-2 Abdominal aortic aneurysm mortality classified by treatment procedures.

Procedure for aneurysm repair	Ruptured aneurysm			Non-ruptured aneurysm
	Cases	30-day death	In-hospital death	Cases	30-day death	In-hospital death
Replacement	911	115	144	6,025	53	82
Exclusion with bypass	11	0	5	27	1	1
EVAR	742	113	141	11,732	43	62
EVAR with branch chimney	17	3	4	187	4	5
Fenestrated/branched EVAR	0	0	0	168	1	1
Hybrid	3	1	1	44	0	0

EVAR: endovascular aneurysm repair

1) Thoracic aortic aneurysm

In consultation with the Japanese Cardiovascular Surgery Database (JCVSD), it was decided that from 2019, surgeries for thoracic aortic aneurysm, including thoracic endovascular aortic repair (TEVAR), performed by vascular surgeons will be registered in JCVSD. Only surgeries for thoracoabdominal aortic aneurysms performed by vascular surgeons will be registered in NCD.

2) Abdominal aortic aneurysm (Tables 2-1 and 2-2)

The total number of surgeries for abdominal aortic aneurysms (including common iliac artery aneurysms) registered in NCD in 2019 was 20,369, showing a slight increase each year from 19,144 cases in 2016, 19,982 cases in 2017, and 20,160 cases in 2018. Of these, 6,936 (34.1%) were replacement surgeries, and 12,893 (63.3%) were stent graft endovascular repair (EVAR), including hybrids. The proportion of EVAR cases has continued to increase gradually since it exceeded 50% in 2013 (60.3% in 2016, 61.4% in 2017, and 61.6% in 2018). This trend can be attributed to the fact that EVAR has become the standard treatment for abdominal aortic aneurysms. Furthermore, the number of replacement procedures, which had been between 7,000 and 8,000 cases, declined slightly, falling below 7,000 cases (Fig. 1).

Fig. 1 Treatment procedure for non-ruptured and ruptured AAA. Comparing the year 2011–2018, the proportion of EVAR selection gradually increased in 2019. AAA: abdominal aortic aneurysm; EVAR: endovascular aneurysm repair.

Among the replacement procedures, 1,439 cases (20.7%) required renal artery clamping, and 372 cases (5.4%) required renal artery reconstruction. With the popularization of EVAR, the number of pararenal artery lesions requiring renal artery clamping has increased gradually from 17.6% in 2016 to 20.2% in 2017, and 19.1% in 2018, approximately 20% in 2019.

Regarding the treatment outcomes for non-ruptured AAAs, the operative and in-hospital mortality rates were 0.9% and 1.4%, respectively, for the replacement procedure, and 0.4% and 0.6%, respectively, for EVAR, including specialized and hybrid procedures (Fig. 2). In cases, requiring renal artery clamping, the mortality rates increased to 1.4% and 2.2%, respectively, and further increased to 1.5% and 2.1%, respectively, when reconstruction was performed.

Fig. 2 Early clinical results of non-ruptured AAA in the year 2011–2019. AAA: abdominal aortic aneurysm.

The number of surgeries for ruptured AAAs was 1,739 and was approximately 1,800 each year. The operative mortality rate was 15.0%, and the in-hospital mortality rate was 18.8%. For ruptured cases, the operative mortality rate was approximately 15%, and the in-hospital mortality rate was just under 20%, which was similar to the results in recent years. EVAR was performed in 762 cases (43.8%), and although there was an increasing trend, the proportion of EVAR for ruptured cases was similar to that in 2018 (35.9% in 2016, 37.9% in 2017, and 43.3% in 2018) (Fig. 1). The operative and in-hospital mortality rates for ruptured cases were 15.4% and 19.2%, respectively, which are similar to the results from recent years: 2016 (15.3% and 18.8%, respectively), 2017 (12.3% and 15.8%, respectively), and 2018 (14.6% and 16.4%, respectively). Despite the increasing number of ruptured EVARs, the outcome has remained stable. This may be due to the increasing experience with EVAR at each institution and the accumulation of experience with EVAR for ruptured cases. Although patient selection bias must be considered (as EVAR is generally performed in anatomically more favorable patients), the results were comparable to those of replacement surgery, which had operative and in-hospital mortality rates of 12.6% and 15.8%, respectively (Fig. 3).

Fig. 3 Early clinical results of ruptured AAA in the year 2011–2019. AAA: abdominal aortic aneurysm.

3) Peripheral aneurysm (Tables 2-3 and 2-4)

Table 2-3 Peripheral artery aneurysm.

Aneurysm	Cases	Gender		Mortality		Ruptured aneurysm			Etiology
		Male	Female	30-day death	In-hospital death	Cases	30-day death	In-hospial death	Degenerative	Vasculitisa	Takayasu arteritis	Connective tissue diseaseb	Infected	Traumas	Others
Aortic arch branches
Carotid	13	12	1	0	0	2	0	0	3	0	0	1	2	1	6
Vertebral	1	0	1	0	0	0	0	0	0	0	0	0	0	0	1
Subclavian	60	41	19	1	4	7	1	2	41	1	0	3	5	3	7
Multiple in arch branches	1	1	0	0	0	0	0	0	1	0	0	0	0	0	0
Others	20	14	6	0	0	2	0	0	9	0	1	1	0	2	7
Upper limb artery
Axillary	26	19	7	1	1	3	1	1	22	0	0	1	2	1	0
Brachial	181	111	70	5	5	30	3	2	55	1	0	0	19	42	64
Forearm-hand	122	67	55	2	4	18	0	0	46	1	0	0	16	27	32
Others	20	14	6	0	0	2	0	0	10	0	0	0	1	2	7
Visceral artery
Celiac	27	22	5	1	1	5	1	1	18	1	0	0	1	0	7
Hepatic	15	11	4	1	1	4	1	1	10	0	0	0	1	0	4
Splenic	93	45	48	0	1	5	0	1	87	0	0	1	1	0	4
Superior mesenteric	41	32	9	3	3	6	1	1	25	0	1	1	8	3	3
Renal	90	63	27	1	1	12	1	1	75	1	0	0	1	2	11
Others	122	100	22	2	2	16	1	1	102	1	0	2	4	2	11
Lower limb artery
External iliac	204	171	33	5	9	28	4	7	159	1	1	1	13	5	24
Internal iliac	1,493	1,274	219	24	31	111	15	19	1,448	4	1	3	15	0	22
Femoral	470	367	103	15	18	97	9	9	214	3	0	0	58	69	126
Popliteal	269	209	60	1	0	14	0	0	240	3	0	0	7	3	16
Others	55	34	21	0	1	7	0	1	25	0	0	0	2	12	16
Total	3,166	2,468	698	60	79	354	36	45	2,453	16	3	12	153	173	356

Table 2-3 Peripheral artery aneurysm (Continued).

Aneurysm	Treatment procedure						Graft material for open surgery
	Replacement	Exclusion with bypass	Ligation/ resection	Stent graft	Coil embolization	Others	Polyester	ePTFE	Autogenous vessel	Others
Aortic arch branches
Carotid	2	0	0	7	0	4	1	0	1	0
Vertebral	0	0	0	0	1	0	0	0	0	0
Subclavian	13	7	4	29	13	7	6	11	3	0
Multiple in arch branches	1	0	0	0	0	0	0	1	0	0
Others	1	0	5	9	7	1	1	2	0	0
Upper limb artery
Axillary	11	7	4	2	1	3	1	7	10	0
Brachial	39	7	90	4	1	52	5	24	16	0
Forearm-hand	9	5	91	0	0	20	0	7	6	0
Others	1	0	13	0	1	5	0	1	0	0
Visceral artery
Celiac	3	1	2	13	11	1	2	1	1	0
Hepatic	2	0	4	4	6	1	1	0	2	0
Splenic	3	1	11	8	69	6	2	0	0	0
Superior mesenteric	3	5	13	10	14	5	0	0	7	0
Renal	11	1	14	27	36	12	3	1	5	1
Others	27	6	17	43	41	7	28	3	3	0
Lower limb artery
External iliac	57	8	11	118	35	10	52	14	0	0
Internal iliac	187	9	136	716	795	44	183	21	1	2
Femoral	157	32	152	39	19	101	57	114	27	0
Popliteal	123	89	47	15	7	16	19	78	113	6
Others	8	6	24	6	8	6	3	7	4	0
Total	586	172	620	1,000	1,027	292	309	271	186	8

a: Including TAO, Takayasu aortitis, collagen disease related vasculitis, Behçet disease, fibromuscular dysplasia.

b: Connective tissue abnormalities such as Marfan syndrome.

Y-graft: Y-shape artificial graft; T-graft: straight artificial graft; Polyester: polyester artificial graft such as Dacron graft; ePTFE: expanded polytetrafluoroethylene graft

Table 2-4  Internal iliac artery aneurysm.

Internal iliac artery aneurysm	Cases
Unilateral solitary	639
Bilateral solitary	202
Associated with AAA	558
Associated with other aneusym	94

AAA: abdominal aortic aneurysm

A total of 3,166 patients were registered, with a male-to-female ratio of 2,468:698, indicating that male cases were more common. Affected regions included the lower limb arteries in 2,491 cases, abdominal visceral arteries in 388 cases, upper limb arteries in 349 cases, and aortic arch branches in 95 cases. It is estimated that 157 cases involved multiple lesions in different regions. Case distribution by artery was as follows: 44.9% in the internal iliac artery, 14.1% in the femoral artery, 8.1% in the popliteal artery, 6.1% in the external iliac artery, and 5.4% in the brachial artery. Of the internal iliac artery aneurysms, 42.8% were unilateral solitary, 13.5% were bilateral solitary, and 37.4% coexisted with abdominal aortic aneurysms. Symptoms were noted in 29.4% of overall cases, with higher rates observed in the brachial (65.2%), femoral (52.8%), and popliteal arteries (55.4%). Rupture occurred in 11.1%. The most common cause was degenerative disease (77.9%). Surgical procedures included coil embolization in 24.5%, stent graft placement in 24.1%, replacement in 16.9%, ligation/resection in 16.4%, and exclusion with bypass in 4.7%, with endovascular treatment accounting for 54.3% of cases. It is inferred that 23.1% of cases involved multiple procedures. The number of registrations increased by 6.3% from 2018, but the incidence by region, etiology, symptomatic cases, and percentage of endovascular procedures were similar to those in 2018.

2. Revascularization for Chronic Arterial Occlusive Disease (Table 3)

1) Aortic arch branch, upper limb, and abdominal visceral arteries (Tables 3-1 and 3-6)

Table 3 Reconstruction for chronic arterial occlusive diseases^a: Table 3-1 Arterial reconstruction for aortic arches.

Aortic branches	Cases	Gender		Mortality	Background	Etiology					Revascularization procedures
		Male	Female	30-day death	Dialysis	ASO	TAO	Vasculitisb	Takayasu arteritis	Others	CAS		CEA		PTA/ stentd		Replacement	Visceral artery bypass	Internal iliac artery bypass
											Cases	Brain complicationc	Cases	Brain complicationc	Cases	Brain complicationc
Carotid artery	267	202	65	9	10	96	0	0	1	170	14	0	70	4	21	0	3	0	0
Vertebral artery	4	4	0	0	0	1	0	0	0	3			0	0	1	0	0	0	0
Subclavian artery	589	450	139	15	41	134	1	1	1	452			0	0	99	0	2	0	0
Multiple lesions of arch branches	29	20	9	0	1	4	0	0	0	25			0	0	2	0	1	0	0
Upper limb including axillar artery	119	75	44	1	62	85	0	2	0	31			0	0	66	0	0	0	1
Celiac/ Superior mesenteric artery	101	71	30	5	8	48	0	0	3	49			0	0	32	0	5	57	6
Renal artery	119	86	33	2	2	71	0	1	0	45			0	0	88	0	1	25	1
Others	0	0	0	0	0	0	0	0	0	0			0	0	0	0	0	0	0
Total	1,043	767	276	23	119	424	1	4	5	605	14	0	70	4	285	0	11	63	8

Table 3-1 Arterial reconstruction for aortic arches (Continued).

Aortic branches	Revascularization procedures					Graft materialse				Previous recontruction					Revision reason
	Anatomical bypass	Carotid-subclavian bypass	Axillo-axillar bypass	Others	Upper limb artery recanalization	Polyester	ePTFE	Autogenous veins	Others	None	Once	Twice	Three times and more	Unclear	Host artery stenosis/ occlusion	Graft stenosis	Graft occlusion	EVT stenosis	EVT occlusion	Stent graft-caused stenosis/ occlusion	Poor symptom recovery	Others
Carotid artery	13	143	87	34	1	50	154	11	11	257	8	1	1	0	1	2	0	2	0	3	0	5
Vertebral artery	0	3	1	1	0	1	2	0	0	4	0	0	0	0	0	0	0	0	0	0	0	0
Subclavian artery	16	277	280	61	4	132	411	2	6	550	27	4	8	0	5	8	8	6	3	4	2	8
Multiple lesions of arch branches	4	5	6	15	1	19	8	0	0	28	1	0	0	0	0	1	0	0	0	0	0	0
Upper limb including axillar artery	5	4	7	27	20	8	16	13	6	73	28	9	7	2	13	5	4	16	3	1	1	3
Celiac/ Superior mesenteric artery	0	0	1	7	0	36	29	16	2	84	12	1	3	1	2	0	0	5	3	1	1	4
Renal artery	0	1	1	6	1	20	14	3	1	100	14	2	1	2	0	2	0	11	0	1	1	3
Others	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Total	26	301	295	118	26	202	496	44	21	920	83	16	19	5	20	16	12	38	9	8	4	21

a: Bypass surgery combined with endovascular treatment is counted in both the bypass category (Table 3-2) and the endovascular category (Table 3-5).

b: Including TAO, Coarctation of aorta, collagen disease related vasculitis, Behçet disease, fibromuscular dysplasia.

c: Postoperative irreversible brain complication.

d: Including percutaneous transluminal angioplasty (PTA), stent, and other endovascular means such as catheter atherectomy.

e: Only for open surgery.

Table 3-2 Arterial reconstruction for chronic lower limb ischemia.

From aorta to lower limb arterial systems	Cases	Gender		Mortality	Dialysis cases	Etiology					Graft materials
		Male	Female	30-day death		ASO	TAO	Vasculitis	Takayasu arteritis	Others	Polyester	ePTFE	Autogenous veins	Others
Aorto-aortic bypass	50	33	17	2	3	43	0	2	1	3	22	9	0	0
Infrarenal aortic reconstruction (suprarenal clamp)	40	31	9	0	1	37	0	0	0	2	15	0	0	0
Aorto-femoral bypassa	497	376	121	2	33	465	2	2	2	23	174	102	16	6
Femoro-popliteal (above the knee) bypass	1,203	880	323	14	164	1,189	1	2	0	11	106	719	219	20
Infrapopliteal arterial bypass	1,865	1,314	551	35	707	1,810	12	10	0	31	49	256	1,480	62
Femoro-popliteal (below the knee) bypass	633	442	191	7	188	621	1	2	0	8	33	187	360	27
Femoro-crural/pedal bypassb	1,250	882	368	28	526	1,207	11	8	0	23	17	74	1,137	35
Extended deep femoral plasty	65	50	15	0	9	63	0	0	0	2	8	17	19	5
Others	84	64	20	1	10	75	0	1	0	6	19	32	23	0
Total	3,698	2,669	1,029	54	915	3,576	15	17	3	78	369	1,094	1,722	90

Table 3-2 Arterial reconstruction for chronic lower limb ischemia (Continued).

From aorta to lower limb arterial systems	Previous reconstruction					Revision reason
	None	Once	Twice	Three times and more	Unclear	Host artery stenosis/occlusion	Graft stenosis	Graft occlusion	EVT stenosis	EVT occlusion	Stent graft-caused stenosis/ occlusion	Poor symptom recovery	Others
Aorto-aortic bypass	45	4	1	0	0	2	0	1	0	0	0	1	1
Infrarenal aortic reconstruction (suprarenal clamp)	34	3	3	0	0	0	0	3	1	2	0	0	0
Aorto-femoral bypassa	419	54	15	7	2	11	11	20	8	14	2	5	8
Femoro-popliteal (above the knee) bypass	863	220	54	58	8	80	21	61	20	83	16	39	26
Infrapopliteal arterial bypass	1,022	445	183	192	23	164	42	154	60	185	19	149	61
Femoro-popliteal (below the knee) bypass	378	133	54	62	6	44	17	59	18	63	11	20	27
Femoro-crural/pedal bypassb	658	315	129	131	17	121	25	95	42	124	8	130	34
Extended deep femoral plasty	37	19	1	8	0	7	2	5	3	5	0	3	4
Others	50	20	6	8	0	9	2	13	2	4	0	1	3
Total	2,392	750	258	265	33	270	75	250	91	284	37	197	101

a: Including aorto-iliac bypass or ilio-femoral bypass.

b: Including popliteal-crural (or pedal) bypass.

Table 3-3 Extra-anatomical bypass^a.

Extra-anatomical bypass	Cases	Gender		Mortality	Dialysis cases	Etiology			Graft materials				Previous reconstruction
		Male	Female	30-day death		ASO	TAO	Others	Polyester	ePTFE	Autogenous veins	Others	None	Once
Carotid-subclavian bypass	301	222	79	11	9	20	0	281	70	256	0	2	291	8
Axillo-axillar bypass	295	227	68	10	14	45	0	250	62	253	1	4	283	9
Axillo-femoral bypassb	204	125	79	5	32	188	0	16	33	164	8	1	163	22
Femoro-femoral crossover bypass	614	491	123	9	62	568	0	45	125	453	32	19	465	102
Others	56	43	13	0	9	45	2	9	7	45	4	2	28	10
Total	1,616	1,192	424	27	157	1,103	2	511	331	1,282	63	29	1,336	185

Table 3-3 Extra-anatomical bypass^a (Continued).

Extra-anatomical bypass	Previous reconstruction			Revision reason
	Twice	Three times and more	Unclear	Host artery stenosis/ occlusion	Graft stenosis	Graft occlusion	EVT stenosis	EVT occlusion	Stent graft-caused stenosis/ occlusion	Poor symptom recovery	Others
Carotid-subclavian bypass	0	2	0	0	2	3	0	0	2	0	4
Axillo-axillar bypass	1	2	0	2	1	3	1	0	2	0	4
Axillo-femoral bypassb	8	8	3	3	2	15	3	6	1	4	7
Femoro-femoral crossover bypass	23	19	4	33	5	40	10	21	11	13	14
Others	5	10	3	1	1	9	1	2	0	3	8
Total	45	39	11	42	13	82	22	36	15	26	41

a: Cases underwent extraanatomical bypass because of graft infection should not be include this category. Those cases are listed in vascular complication (Table 6-1).

b: A case that underwent axillo-femoro-femoral crossover bypass is counted as one case. A case combined with an additional contralateral side of the axillo-femoral bypass as second staged surgery is counted as 2 cases.

Table 3-4 Thromboendarterectomy^a for chronic lower limb ischemia.

Thromboendarterectomy	Cases	Gender		Mortality	Dialysis cases	Etiology			Previous reconstruction					Revision reason
		Male	Female	30-day death		ASO	TAO	Others	None	Once	Twice	Three times and more	Unclear	Host artery stenosis/ occlusion	Graft stenosis	Graft occlusion	EVT stenosis	EVT occlusion	Stent graft-caused stenosis/ occlusion	Poor symptom recovery	Others
Aorto-iliac lesion	74	52	22	2	17	71	2	1	52	15	3	4	0	6	3	0	3	3	2	2	5
Femoro-popliteal lesion	1,239	922	317	12	329	1,233	2	4	940	187	49	57	6	115	10	24	47	50	2	26	30
Othersb	577	421	156	27	149	527	4	46	301	145	48	70	13	31	41	28	25	20	8	36	77
Total	1,864	1,375	489	41	492	1,805	8	51	1,275	340	99	131	19	151	51	52	73	73	12	64	109

a: Including patch plasty.

b: Including reconstruction, thrombolysis and others.

Table 3-5 Endovascular treatment for chronic lower limb ischemia^a.

Endovascular treatment	Cases	Gender		Mortality		Dialysis cases	Etiology			Previous reconstruction					Revision reason
		Male	Female	30-day death	In-hospital death		ASO	TAO	Others	None	Once	Twice	Three times and more	Unclear	Host artery stenosis/ occlusion	Graft stenosis	Graft occlusion	EVT stenosis	EVT occlusion	Stent graft-caused stenosis/ occlusion	Poor symptom recovery	Others
Aorto-iliac lesionb	4,281	3,363	918	35	49	640	4,214	3	64	3,377	553	172	154	25	301	59	53	267	89	46	35	52
Femoro-popliteal lesionb	5,091	3,521	1,570	50	89	1,476	5,063	4	24	3,035	1,088	418	521	29	548	204	120	615	303	62	126	78
Infrapopliteal-ankle lesionb	2,743	1,743	1,000	50	92	1,358	2,716	11	16	1,333	599	266	531	14	286	197	114	351	286	14	127	36
Others	230	147	83	3	7	121	221	2	7	28	42	42	116	2	10	114	46	12	9	1	4	5
Total (number of lesions underwent EVT)b	10,581	7,587	2,994	117	207	2,950	10,463	17	101	6,719	1,923	751	1,126	62	977	507	274	1041	557	106	246	152
Total (number of limbs underwent EVT)c	8,879	6,440	2,439	98	179	2,330	8,774	14	91	5,703	1,574	611	937	54	815	441	216	845	431	91	201	134

a: Including PTA, stent, and other endovascular means such as catheter atherectomy.

b: When endovascular treatment performed for multiple lesions, the case should be counted in each lesions (If a case underwent endovascular treatment in both aorto-iliac and femoro-popliteal lesion, this case can be counted one in aorto-iliac, and one in femoro-popliteal lesion).

c: Counting the patients number not treated lesions. When a case underwent endovascular treatment in multiple lesion, the case is counted as one case.

ASO: arteriosclerosis obliterans; TAO: thromboangitis obliterans (Buerger's disease); CAS: carotid artery stenting; CEA: carotid endarterectomy; PTA: percutaneous transluminal angioplasty; EVT: endovascular treatment; IIA: internal iliac artery

Table 3-6 Debranch for TEVAR or EVAR.

Debranch for TEVAR or EVAR	Cases
Ascending aorta-brachiocephalic-left common carotid(-left subclavian) arterial bypass	15
Right axillar-left common carotid(-left axillary) arterial bypass	271
Right common carotid-let common carotid(-left subclavian) arterial bypass
Left common carotid-left subclavian arterial bypass or transposition
Right axillar (subclavian)-left axillar (subclavian) arteril bypass	237
Abdominal aorta (iliac) (-celiac)-superior mesenteric-renal arterial bypass	45

EVAR: endovascular aneurysm repair; TEVAR: thoracic endovascular aortic repair

In 2019, there was an overall decreasing trend, with 267 cases of carotid artery, 4 cases of vertebral artery, 589 cases of subclavian artery, 29 cases of multiple lesions of aortic arch branches, and 119 cases of axillary and upper extremity artery conditions. The celiac and superior mesenteric arteries showed an increase from 83 cases in 2018 to 101 cases. The number of carotid artery stenting (CAS) and carotid endarterectomy (CEA) carotid arteries increased from 77 cases in 2018 to 84 cases in 2019 but remained below 112 cases recorded in 2017. Surgical revascularization was performed in 83% of subclavian artery lesions, which was similar to the previous year in terms of technique. Among lesions of the axillary and upper extremity arteries, 45% were treated surgically, with a high proportion of dialysis patients at 52%, up from 41% in the previous year.

Regarding debranching with TEVAR/EVAR, the number of registered cases was 15 for ascending aorta–brachiocephalic–left common carotid (–left subclavian) arterial bypass, 271 for right axillar (subclavian)–left common carotid arterial bypass, 237 for right axillary (subclavian)–left axillary (subclavian) arterial bypass, and 45 for abdominal aorta–superior mesenteric artery–renal artery bypass. Compared to 2018, this represents a decrease of 29%, 8%, and 26%, and an increase of 136%, respectively, indicating a decline in cases except for abdominal debranching.

2) Anatomical bypass (Table 3-2), non-anatomical bypass (Table 3-3), thromboendarterectomy (Table 3-4), and endovascular treatment (Table 3-5) in the aorta–lower extremity artery region

Aortoiliac artery territory: For anatomic bypass in lesions of the aortoiliac artery region, the number of cases increased slightly from 553 in 2018 to 587 in 2019, reflecting a 6% increase, with no changes noted in the breakdown, including etiology and graft vessel used. However, for non-anatomic revascularization procedures, such as axillary–femoral and femoral–femoral artery bypass, the number of cases decreased from 311/719 in 2018 to 204/614 in 2019, indicating a 34%/15% decrease (Fig. 4A).

Fig. 4 The annual trends of the number of arterial reconstructions in aorto-iliac (A), femoro-popliteal (B), and crural/pedal region (C), comparing open repair and endovascular treatment. Ao-F: aorto-femoral; Ax-F: axillo-femoral; F-F: femoro-femoral crossover; EVT: endovascular treatment; FPAK: femoropopliteal (above the knee); FPBK: femoro-popliteal (below the knee); SFA: superficial femoral artery; TEA: thromboendarterectomy.

Femoropopliteal artery region: Femoral–above-knee popliteal artery bypass surgeries decreased for the second consecutive year by 4.3%, from 1,257 cases in 2018 to 1,203 cases in 2019, and by 13.9% from 2017 (1,348 cases) to 2019 (Fig. 4B). Artificial vessels accounted for 69% of the grafts (ePTFE/polyester = 60%/9%), whereas the use of autologous veins remained at 18%, similar to that in 2018 (22%). In addition, revascularization to the popliteal artery below the knee decreased by 8%, from 690 cases in 2018 to 633 cases in 2019 (Fig. 4B). Autologous veins comprised 57% of grafts, similar to 59% in 2018. Regarding previous revascularization, 28% of patients underwent above-knee bypass, 39% underwent below-knee bypass, and among dialysis patients, 14% underwent above-knee bypass and 30% underwent below-knee bypass, with no significant difference from the previous year.

Below-knee and foot region: Bypass procedures of the lower leg and foot were similar to the previous year, with 1,292 cases in 2018 and 1,250 cases in 2019 (Fig. 4C). Autologous veins were used as the graft in 91% of cases, similar to the previous year (91%), and dialysis cases accounted for 42%, which was similar to the previous year (40%). Previous revascularization was noted in 46% of cases, suggesting that the frequency of previous revascularization tends to increase with more distal bypass.

Thromboendarterectomy (Table 3-4): Regarding thromboendarterectomy cases of lower extremity arteries, cases in the iliac artery region decreased by 14%, from 86 cases in 2018 to 74 cases in 2019. By contrast, cases in the femoral–popliteal artery region increased by 7%, from 1,159 cases in 2018 to 1,239 cases in 2019. Cases classified as other, including vascular replacement, decreased by 3%, from 597 cases in 2018 to 577 cases in 2019. As a result, the total number of cases in 2019 increased by 5% compared to 2018. For extended deep femoral arterioplasty, the number of cases in 2019 was 65, which was similar to 64 cases in 2018.

Endovascular treatment (Table 3-5): The total number of endovascular treatments was 8,879 cases, representing an increase of 878 cases, or approximately 10%, compared to 2018. Of these, 26% were performed on dialysis patients. Surgical revascularization procedures (bypass, thromboendarterectomy) in the lower limb region showed varying trends by region, but overall, there was a gradual decrease in the total number, whereas endovascular procedures continued to increase over time. By region, the iliac artery region showed the highest increase, with a 13% increase from 3,774 cases in 2018 to 4,281 cases in 2019. The femoral–popliteal artery region showed a 7% increase, whereas endovascular treatment in the lower leg artery region remained unchanged, with the same number of cases as the previous year (Figs. 4A–4C).

3. Revascularization for Acute Arterial Occlusion (Table 4)

Table 4 Revascularization for acute arterial occlusive disease^a.

Obstructive arteryb	Cases	Gender		Mortality		Etiology			Procedure						Graft materials for open surgery
		Male	Female	30-day death	In-hospital death	Embolism	Thrombosisc	Others	Thrombectomy ± patchd	Bypass	Replacement	PTA ± stent	Thrombolysis	Others	Autogenous vessel	Polyester	ePTFE	Others
Carotid artery	16	10	6	2	2	3	5	8	4	4	3	5	0	1	0	2	5	1
Subclavian artery	70	34	36	8	10	29	24	17	37	17	2	12	0	6	0	4	14	0
Axillary artery	79	42	37	6	7	50	20	9	61	10	0	1	0	7	1	2	8	0
Brachial artery	690	336	354	30	32	337	336	17	573	18	5	48	2	68	11	6	12	0
Celiac/superior mesenteric artery	117	75	42	26	36	50	38	29	48	23	2	38	3	11	14	4	7	0
Renal artery	39	31	8	4	7	11	10	18	8	7	2	21	0	4	1	5	6	1
Abdominal aorta-iliac artery	846	616	230	90	105	316	406	124	535	207	18	251	6	43	13	76	167	10
Femoro-popliteal artery	2,837	1,769	1,068	191	268	1,262	1,465	110	2,292	315	26	486	28	174	149	109	223	12
Crural artery	891	578	313	73	96	397	474	20	679	86	5	196	13	85	55	34	36	6
Pedal arterye	86	64	22	6	7	35	46	5	54	13	0	19	3	14	9	4	3	2
Others	252	141	111	12	16	52	182	18	191	17	1	48	7	28	7	7	19	0
Total	4,947	3,051	1,896	351	476	2,080	2,525	342	3,690	596	54	887	47	380	216	218	424	26

a: Cases with non-traumatic acute arterial occlusion are listed in this table. Please see Table 5-1 for acute arterial occlusion by trauma.

b: If the primary occlusion site cannot be identified, the most proximal lesion is described.

c: Cases with acute exacerbation of chronic lesion are excluded. Treatment for those cases are listed in Table 3.

d: If either thrombectomy or patch plasty is performed, cases are listed in this section.

e: Including acute occlusion of dorsalis pedis or plantar artery.

PTA: percutaneous transluminal angiography; ePTFE: expanded polytetrafluoroethylene

Excluding vascular trauma, there were 4,947 cases of acute arterial occlusion, and the total number of occlusions by region was 5,923 cases, suggesting that 976 cases (16%) involved simultaneous occlusions at multiple sites. The affected sites included the abdominal aorta and infra-aortic peripheral arteries in 4,660 cases (79%), upper limb arteries (subclavian, axillary, and brachial) in 839 cases (14%), and abdominal viscera (celiac, superior mesenteric, and renal arteries) in 156 cases (2.6%). The etiology was thrombosis in 50% of cases, embolism in 40%, and other causes in 10%, which was consistent with previous years. Of the 4,947 cases, 934 (19%) underwent endovascular treatment, including percutaneous transluminal angioplasty (PTA) with or without stent, and thrombolysis, which was almost the same as the previous year. By region, endovascular treatment was performed in 30% of abdominal aorta–iliac artery, 18% of femoral–popliteal arteries, 23% of crural arteries, and 26% of pedal artery cases. For femoral–popliteal artery cases, thrombectomy was performed in 81% of cases, and 12% required revascularization (bypass or replacement). For crural artery cases, thrombectomy was performed in 76%, and revascularization was performed in 10%. The operative and in-hospital mortality rates were 11%/12% for the abdominal aorta–iliac artery (10%/12% in the previous year), 7%/9% for the femoral–popliteal artery (7%/9% in the previous year), 8%/11% for the crural artery (8%/11% in the previous year), and 7%/8% for the pedal artery (15%/17% in the previous year). As in previous years, the prognosis was clearly poorer compared to elective revascularization surgery. The operative and in-hospital mortality rates for the celiac and superior mesenteric arteries were 22%/31% (16%/24% in the previous year), indicating a very poor prognosis, consistent with previous years.

4. Treatment of Vascular Trauma (Table 5)

Table 5 Treatment for vascular trauma^a: Table 5-1 Arterial trauma.

Injured artery	Cases	Gender		Mortality		Cause of trauma				Procedure
		Male	Female	30-day death	In-hospital death	Traffic accident	Labor accident	Iatrogenic	Others	Direct closure	Patch plasty	Replacement
Carotid artery	39	17	22	5	10	0	0	29	10	17	1	0
Subclavian artery	78	51	27	9	14	8	3	54	13	21	1	2
Axillar artery	23	14	9	0	0	4	4	12	3	7	0	1
Brachial artery	362	216	146	8	13	5	12	304	41	240	2	17
Descending aorta (thoracic/thoracoabdominal)	26	20	6	8	9	9	1	5	11	6	2	1
Celiac/ superior mesenteric artery	69	44	25	7	7	18	1	27	23	12	1	1
Renal artery	27	19	8	2	3	3	2	14	8	5	0	2
Abdominal aorta-iliac artery	266	149	117	36	38	32	14	165	55	66	5	14
Femoro-popliteal artery	991	589	402	72	94	23	31	848	89	682	40	37
Crural artery	44	25	19	0	0	7	6	15	16	11	2	1
Others	318	180	138	15	23	16	27	184	91	135	0	6
Total	2,186	1,298	888	154	202	109	97	1,635	345	1,193	51	77

Table 5-1 Arterial trauma (Continued).

Injured artery	Procedure				Status of injured artery						Prosthesis
	Bypass	Endo-vascular	Ligation	Others	Obstruction/stenosisb	Bleeding without specificationc	GI fistula	Non-GI fistula	Pseudo-aneurysm	Others	Autogenous vessel	Polyester	ePTFE	Others
Carotid artery	2	10	5	5	6	21	1	5	2	4	0	0	2	1
Subclavian artery	8	32	8	10	15	34	1	2	10	17	5	1	6	0
Axillar artery	8	4	2	2	10	7	0	1	6	3	5	0	4	0
Brachial artery	15	13	55	38	23	46	0	8	237	64	23	2	8	0
Descending aorta (thoracic/ thoracoabdominal)	4	6	1	7	1	16	0	0	5	5	1	3	4	0
Celiac/ superior mesenteric artery	9	41	1	6	15	36	4	2	8	5	7	2	2	0
Renal artery	1	18	2	0	4	16	0	2	3	4	0	3	0	0
Abdominal aorta-iliac artery	28	134	16	29	48	130	9	14	47	37	1	24	23	1
Femoro-popliteal artery	77	68	70	81	103	226	0	7	553	152	62	29	55	9
Crural artery	15	9	7	4	9	15	0	0	15	6	15	1	2	0
Others	6	64	83	41	27	155	2	8	71	61	3	2	10	0
Total	161	371	247	213	236	675	17	46	950	355	117	59	108	10

a: Iatrogenic pseudoaneurysm in endovascular treatment is listed in this table.

b: Including arterial dissection.

c: Without GI fistula or non-GI fistula. Cases with vessel injury involving both vein and accompanying artery are listed in this table.

GI: gastro-intestinal; ePTFE: expanded polytetrafluoroethylene

Table 5-2 Venous trauma.

Injured veins	Cases	Cause of trauma				Procedure							Prosthesis
		Traffic accident	Labor accident	Iatrogenic	Others	Direct closure	Patch plasty	Replacement	Bypass	Endo-vascular	Ligation	Others	Autogenous vessel	Polyester	ePTFE	Others
Superior vena cava	5	0	1	3	1	4	0	0	0	0	0	1	0	0	0	0
Inferior vena cava	20	1	3	10	6	14	1	1	0	1	1	3	1	0	0	1
Brachiocephalic- subclavian vein	9	1	2	5	1	7	0	0	1	0	1	2	1	0	0	0
Iliac-femoral- popliteal vein	48	1	1	40	6	32	0	1	3	8	7	6	1	1	2	0
Others	103	3	7	46	47	65	1	2	4	1	26	10	7	0	0	0
Total	183	6	13	103	61	120	2	4	8	10	35	22	10	1	2	1

ePTFE: expanded polytetrafluoroethylene

The site of vascular trauma, cause of injury, procedure, and type of graft used in the 2019 NCD registry data are shown in Table 5. The total number of arterial and venous trauma cases was 2,369. The most common cause of vascular trauma was iatrogenic, accounting for 1,738 cases (73%), followed by traffic accidents in 115 cases (5%), and labor accidents with 110 cases (5%). A total of 2,428 sites of vascular injury were recorded, with the most common site being the arteries of the lower extremities, accounting for 1,035 cases (43%), followed by the arteries of the upper extremities with 463 cases (19%), and the abdominal aorta–iliac artery with 266 cases (11%). Regarding the procedure, direct suturing was used in 1,313 cases (52%), endovascular treatment in 381 cases (15%), and ligation in 282 cases (11%) (Fig. 5A). Vascular grafts were used in 308 cases, with 38% of these grafts being autologous.

Fig. 5 Treatment procedure and location of vascular trauma in the year 2019. Operation mode (A), location vascular trauma by iatrogenic (B), traffic accident (C), and work-related accident (D).

1) Iatrogenic vascular trauma

Examination by site revealed that, among the 1,738 cases of iatrogenic vascular trauma at 1,761 sites, the lower extremity arteries were most commonly affected (863 sites, 49%), followed by the upper extremity arteries (370 sites, 21%), together accounting for 70% of the total. Most of these injuries were believed to be complications from puncture sites associated with endovascular catheterization and treatment (Fig. 5B).

2) Traffic accidents

Of 131 sites in 115 cases of traffic accidents, the most commonly injured were the upper and lower limb arteries (47 sites, 36%), followed by the abdominal aorta and iliac arteries (32 sites, 24%), visceral arteries (21 sites, 16%), and the descending aorta and thoracoabdominal aorta (9 sites, 7%) (Fig. 5C). Vessels in the extremities, being closer to the body surface, are assumed to be more susceptible to direct external force. However, unlike vascular trauma from other causes, injuries to the thoracic and abdominal aorta, which are protected by the thoracic cage and abdominal wall, make up a significant proportion of traffic accident injuries. This is likely due to high-energy trauma involving rapid deceleration, such as in collisions.

3) Occupational injuries

This category is based on the assumption of labor accidents, such as falling from a high place or being caught in a machine tool, with 110 cases and 115 sites registered, respectively. By site, the arteries of the extremities, which are close to the body surface and more susceptible to external forces, accounted for 49% of the 56 sites (Fig. 5D).

5. Surgery for Complications after Revascularization (Table 6)

1) Prosthetic graft infection (Table 6-1)

Table 6 Revascularization for vascular complication after revascularization: Table 6-1 Graft infection.

Position of infected garft	Cases	mortality		Status of infected graft				Proceduere for graft infection				Material for revision or redo surgery
		30-day death	In-hospital death	Sepsis	Graft-GI fistulab	Garaft-skin fistulab	Others	In-situ replacement	Extra-anatomical bypass	Prosthetic graft extirpation	Others	Polyester	ePTFE	Autogenous vessel	Cryo-preserved homograft	Others
Descending thoracic aorta	2	0	0	0	0	1	1	0	0	0	2	1	0	0	0	0
Thoracoabdominal aorta	13	1	1	2	7	0	4	5	0	1	7	3	1	2	0	0
Abdominal aorta-iliac artery	78	10	20	36	20	4	21	39	18	4	17	33	19	5	0	8
Abdominal aorta-femoral artery	35	2	2	12	2	16	8	4	10	14	7	8	6	4	0	0
Femoro-distal artery	104	4	10	20	0	55	34	10	23	44	27	5	40	18	0	3
Othersa	174	7	16	33	9	61	79	19	34	79	42	23	50	17	0	4
Total	406	24	49	103	38	137	147	77	85	142	102	73	116	46	0	15

a: Cases with graft infection involving aortic arch branch or upeer limb artery are listed on this column.

b: Including anastomotic disruption.

GI: gastrointestinal; ePTFE: expanded polytetrafluoroethylene

The number of cases registered remained unchanged compared to 2018, with 406 cases. By site, “other,” which includes upper extremity arteries, accounted for 42.9% of all cases, reflecting a trend similar to previous years. Approximately half of the cases in the “other” category involved only graft excision, suggesting that many of these cases were likely due to graft infections in the arteriovenous fistula. In the aorta–iliac and aorta–femoral artery regions, sepsis occurred in approximately 40% of patients, and graft–gastrointestinal fistulas occurred in approximately 20% of patients, with a 30-day postoperative mortality rate of 10.6%. In the femoral–peripheral artery region, sepsis occurred in approximately 20% of patients, and graft–skin fistula occurred in approximately half of the patients, with a 30-day postoperative mortality rate of 3.8%.

2) Anastomotic aneurysm (non-infected) (Table 6-2)

Table 6-2 Anastomotic aneurysm^a.

Location of anastomotic aneurysm	Cases	Mortality	Rupture		Cause of aneurysm treated at the primary operation					Repair procedure				Material for repair surgery
		30-day death	Cases	30-day death	Degenerativeb	Takayasu arteritis	Other vasculitisc	Infection	Others	Replacement	Excludion and bypass	Stent graft	Others	Polyester	ePTFE	Autogenous vessel	Others
Aortic arch branch	9	0	1	0	1	0	2	0	6	2	0	6	1	5	1	0	2
Upper limb artery including axillar artery	14	0	2	0	6	0	0	1	7	0	0	2	12	1	0	1	0
Thoracic aorta	4	0	1	0	1	0	0	0	3	0	0	1	3	0	0	0	1
Splanchnic artery	7	0	2	0	3	0	1	0	3	1	0	3	3	1	1	0	1
Renal artery	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Abdominal aorta	39	3	13	1	28	0	0	0	11	11	1	26	2	16	7	2	4
Iliac artery	25	1	8	1	10	0	1	3	11	3	0	19	4	6	3	1	4
Femoral artery	51	2	13	1	24	1	5	4	17	17	5	4	26	12	17	5	0
Popliteal or more distal lower limb artery	13	0	3	0	8	0	0	2	3	2	3	2	6	1	3	4	1
Total	159	6	42	3	80	1	8	10	60	35	9	61	57	42	32	12	13

a: Cases with infected pseudoaneurysm located at the anastomotic site to the artificial graft are listed in Table 6-1.

b: Including the atherosclerotic aneurysm.

c: Including TAO, collagen disease, Behçet disease, and fibromuscular dysplasia.

ePTFE: expanded polytetrafluoroethylene; TAO: thromboangitis obliterans (Buerger’s disease)

The number of cases has remained almost unchanged over the past several years. The abdominal aorta–iliac artery and lower extremity arteries below the femoral artery each accounted for approximately 40% of the cases. Approximately one-quarter of the cases were ruptured. The treatment involved stent graft insertion in approximately 40% of cases, with the proportion increasing steadily each year.

3) Autologous vascular graft aneurysm (Table 6-3)

Table 6-3 Autogenous graft aneurysm.

Revascularization area	Cases	Mortality	Repair procedure
		30-day death	Replacement	Bypass	Others
Visceral artery	3	1	1	0	2
Upper limb artery	10	0	0	1	9
Lower limb artery	30	0	6	9	15
Others	2	0	1	0	1
Total	45	1	8	10	27

The number of cases remained almost unchanged, with lower extremity arteries accounting for two-thirds of the cases.

4) Prosthetic graft deterioration (Table 6-4)

Table 6-4 Graft degeneration.

Revascularization	Cases	Mortality	Initial revascularization procedure				Degenerative material			Repair procedure					Graft material
		30-day death	Replacement	Bypass	Stent graft	Others	Polyester	ePTFE	Others	Replacement	Bypass	Stent graft	Patch plasty	Others	Polyester	ePTFE	Others
Desceding thoracic aorta	1	0	1	0	0	0	0	1	0	0	0	0	0	1	0	0	0
Thoracoabdominal aorta	1	0	1	0	0	0	1	0	0	0	1	0	0	0	0	1	0
Abdominal aorta-femoral artery	18	0	6	6	3	3	15	2	1	2	4	5	0	7	7	4	4
Femoro-popliteal artery	17	0	2	12	1	3	3	12	2	5	5	1	0	7	2	7	1
Others	29	0	11	13	2	4	16	10	3	11	4	4	2	9	8	12	5
Total	64	0	20	30	6	10	34	24	6	17	14	10	2	23	16	24	10

ePTFE: expanded polytetrafluoroethylene

The number of registered patients decreased by approximately 10% from the previous year to 64 cases, continuing the downward trend. Of these, approximately 10% of graft deterioration cases occurred after stent grafting. Among the materials of the degenerated grafts, polyester and ePTFE accounted for 53.1% and 37.5%, respectively.

6. Venous Surgery (Table 7)

1) Lower extremity varicose veins (Table 7-1)

Table 7 Venous surgery: Table 7-1 Varicose veins.

Varicose veins treatment	Casesa	Male	Female	30-day death
Saphenous vein treatmentsa
High ligation	2,258	780	1,478	0
Stripping	5,239	2,125	3,114	0
Endovenous thermal ablation	41,676	15,172	26,504	2
EVLA	23,749	8,486	15,263	2
RFA	17,877	6,666	11,211	0
Valvuloplasty	2	1	1	0
Perforating vein treatmentsa
Ligation (Direct surgery)	439	171	268	0
SEPS	58	27	31	0
Varicose veins treatmentsa
Avulsion	824	282	542	0
Sclerotherapy	1,473	304	1,169	0
Others	249	90	159	0
Totalb	52,218	18,952	33,266	2

a: Only one procedure can be registered in one leg.

b: Total number of surgeries.

EVLA: endovenous laser ablation; RFA: radiofrequency ablation; SEPS: subfascial endoscopic perforator surgery

The number of target tabulating facilities decreased from 909 in 2018 to 905 in 2019. The number of varicose vein surgeries had been increasing steadily through the NCD-based surveys up until 2016 but began to decline in 2017, further dropping to a total of 43,133 in 2018 and 42,131 in 2019. A 2.4% decrease from the previous year was noted, with an average of 47 procedures per center per year. Endovascular thermal ablation (ETA) includes endovenous laser ablation (EVLA) and radiofrequency ablation (RFA). In 2019, EVLA and RFA were performed in 23,749 cases and 17,877 cases, respectively, with the proportion of EVLA cases increasing from the previous year. Stripping and high ligation remained unchanged, with ETA continuing to be the mainstay of treatment, accounting for 79.8% of the total number of procedures (Fig. 6). With the approval of cyanoacrylate embolization¹⁵⁾ and the statement on inappropriate treatments, further changes in treatment methods are expected in the future.

Fig. 6 Changes in varicose veins treatment in the year 2011–2019. EVLA: endovenous laser ablation; RFA: radiofrequency ablation.

2) Deep vein thrombosis of the lower limbs (including deep vein stenosis/occlusion) (Table 7-2)

Table 7-2 Deep vein thrombosis (including venous stenosis or obstruction).

Deep vein thrombosis treatment	Cases	Male	Female	30-day death
Thrombectomy	35	18	17	1
Catheter-directed thrombolysisa	41	26	15	0
Bypass (peripheral venous reconstruction)	6	5	1	0
IVC filter insertionb	207	87	120	2
IVC filter retrievalb	108	44	64	1
Direct surgery of stenosisc	1	1	0	0
Endoluminal treatment of stenosis	12	6	6	0
Others	9	5	4	0
Total	384	170	214	4

a: Including the catheter-directed thrombolysis using hydrodynamic thrombectomy catheter.

b: Including temporary IVC filter.

c: Including obstruction.

IVC: inferior vena cava

Surgery for lower extremity deep vein thrombosis was registered in 384 cases, decreasing from 449 cases in 2018. Although the number of surgeries related to inferior vena cava filters decreased with increased awareness of the guidelines, 207 cases (53.9%) involved filter insertion, and 108 cases (28.1%) involved filter retrieval, representing the majority. The removal rate was 52.2% (down from 61.4% in the previous year), reflecting a significant decrease in removals (−27.1%) compared to insertions (−14.1%) from 2018. The number of catheter-directed thrombolysis cases was 41 (10.6%), compared to 45 (10.0%) from the previous year, showing no significant change.

3) Upper limb and jugular vein stenosis/obstruction (Table 7-3)

Table 7-3 Upper limb vein stenosis or obstruction.

	Cases	Male	Female	30-day death
Thrombectomy	95	59	36	0
Catheter-directed thrombolysisa	5	5	0	0
Bypass	41	32	9	0
SVC filter insertionb	1	1	0	0
Direct surgery of stenosis	8	5	3	0
Endovascular treatment of stenosis	92	54	38	1
Others	8	4	4	0
Total	204	131	73	1

a: Including the catheter-directed thrombolysis using hydrodynamic thrombectomy catheter.

b: Including temporary IVC filter.

SVC: superior vena cava; IVC: inferior vena cava

The number of upper extremity and jugular vein procedures increased from 148 cases in 2016 to 157 cases in 2017 and 213 cases in 2018 but decreased by 4.3% from the previous year to 204 cases in 2019. Thrombectomy decreased from 106 cases (49.8%) in 2018 to 95 cases (46.6%) in 2019, showing a decline from the previous year. Bypass procedures also showed a decreasing trend, from 54 cases (25.4%) in 2018 to 41 cases (19.7%) in 2019, while endovascular treatment increased from 63 cases (29.6%) in 2018 to 92 cases (45.1%) in 2019.

4) Vena cava reconstruction (Table 7-4)

Table 7-4 Vena cava reconstruction.

Vena cava reconstruction cases	Cases	Mortality		Etiology			Treatment procedures					Material for open surgery
		30-day death	In-hospital death	Tumor	Thrombus	Others	Patch plasty	Bypass	Replacement	PTA ± stent	Others	Polyester	ePTFE	Autogenous vein	Autogenous artery	Cryopreserved vessel	Others	Unused
SVC reconstruction	13	0	0	9	2	2	3	5	2	3	1	0	6	1	0	0	4	2
IVC reconstruction	37	0	1	35	0	2	10	1	13	1	12	3	8	7	0	0	3	16
Total	50	0	1	44	2	4	13	6	15	4	13	3	14	8	0	0	7	18

IVC: inferior vena cava; SVC: superior vena cava; PTA: percutaneous transluminal angiography; ePTFE: expanded polytetrafluoroethylene

The ratio of inferior vena cava reconstruction to superior vena cava reconstruction was similar to that of the previous year, although the number of vena cava surgeries was 50, which was slightly lower than that of the previous year. The most common cause was tumor (44 cases, 88.0%), and there was one death without surgery and one death in hospital, accounting for 2.0%.

5) Budd–Chiari syndrome (Table 7-5)

Table 7-5 Budd-Chiari syndrome.

Treatment	Cases	Gender		Mortality		Material for open surgery
		Male	Female	30-day death	In-hospital death	Polyester	ePTFE	Autogenous veins	Autogenous artery	Cryopreserved vessels	Others	Unused
Shunting	0	0	0	0	0	0	0	0	0	0	0	0
Percutaneous shunting (TIPS)	0	0	0	0	0	0	0	0	0	0	0	0
Direct surgery of stenosis	2	2	0	0	0	0	1	0	0	0	0	1
Endoluminal treatment of stenosis	0	0	0	0	0	0	0	0	0	0	0	0
Liver transplantation	0	0	0	0	0	0	0	0	0	0	0	0
Total	2	2	0	0	0	0	1	0	0	0	0	1

TIPS: transjugular intrahepatic portosystemic shunt; ePTFE: expanded polytetrafluoroethylene

There were no registered cases of transjugular intrahepatic portosystemic shunt (TIPS) in this study, with only 2 cases of direct surgery registered.

6) Others (Table 7-6)

Table 7-6 Other surgery.

Treatment	Cases	Gender		Mortality
		Male	Female	30-day death	In-hospital death
Plication of deep venous aneurysma	10	2	8	0	0
Plication of abdominal venous aneurysm	4	2	2	0	0
Others	1,151	632	519	27	77
Total	1,165	636	529	27	77

a: Including patch plasty.

There were 10 cases of aneurysmorrhaphy for deep venous aneurysm and 4 cases of surgery for visceral venous aneurysm, both representing a small number of surgeries, similar to the numbers in 2018.

7. Other Vascular Diseases and Associated Procedures (Table 8)

Vascular access surgeries continued to increase significantly in 2019 compared to 2018, while the number of other surgeries remained stable, showing no significant changes from previous years.

1) Popliteal artery entrapment syndrome and adventitial cystic disease (Tables 8-1 and 8-2)

Table 8 Other vascular diseases: Table 8-1 Popliteal artery entrapment syndrome.

Treatment	Cases	30-day death
Myotomy	20	0
Revascularization	16	0
Total	26	0

Table 8-2 Adventitial cystic disease.

Treatment	Cases	30-day death
Cyst excision ± patch plasty	25	0
Replacement	8	0
Bypass	6	0
Total	35	0

The number of cases has remained almost unchanged over the past few years, and the disease continues to be rare.

2) Thoracic outlet syndrome (Table 8-3)

Table 8-3 Throracic outlet syndrome (TOS).

Treatment	Cases	Male	Female	30-day death	Type of TOSa
					Neurogenic	Venous	Arterial
Rib resectionb	7	4	3	0	6	0	2
Rib resection + scalenectomy	7	4	3	0	7	0	1
Bypass	1	0	1	0	1	0	1
Total	14	8	6	0	13	0	3

a: In the case with mixture type, the type having the most significant impact on the clinical symptom is listed. But, if the impacts are similar, multiple response is allowed.

b: Including cervical rib.

The number of cases has remained almost unchanged over the past few years, and the disease continues to be rare.

3) Vascular access procedures (Table 8-4)

Table 8-4 Vascular access operation.

Treatment	Cases	30-day death
Arteriovenous access creation by autogenous material	16,061	133
Arteriovenous access creation by artificial materiala	4,050	59
Open surgery for access repair	3,822	33
Endovascular access repair	21,272	93
Arterial transposition	611	10
Arteriovenous access aneurysm repair	565	5
Venous transposition with arteriovenous access creation	187	3
Arteriovenous access closure	584	13
Artificial graft extirpation	453	10
Total	47,605	359

a: Including cases with access repair using artificial graft.

While the number of cases has generally increased every year, this year also saw an increase of 3,600 cases compared to last year, with a particular increase in PTA cases, as was the case in the previous year.

4) Lymphedema surgery (Table 8-5)

Table 8-5 Surgery for lymphedema.

Treatment	Cases	Male	Female	30-day death
Lymphovenous anastomosis	13	3	10	0
Lymph drainage operation	1	0	1	0
Resection	25	16	9	0
Total	39	19	20	0

Although the number of cases has decreased slightly compared to last year, it remains a rare procedure.

5) Sympathectomy (Table 8-6)

Table 8-6 Symphatectomy.

Symphatectomy	Cases	30-day death
Thoracic sympathectomy	29	0
Lumbar sympathectomy	3	0
Total	32	0

As in the previous year, >30 cases were reported this year, but it remains a rare procedure.

6) Upper and lower extremity amputations (Tables 8-7, 8-8)

Table 8-7 Amputation of upper limb.

Amputation level	Cases	30-day death
Digit	10	0
Forearm/ upper arm	6	2
Total	16	2

Table 8-8 Amputation of lower limb^a.

Amputation level	Cases	30-day death	Etiology
			ASO	DM-ASO	TAO	Others
Toe	689	12	241	387	1	60
Transmetatarsal	361	17	79	245	1	36
Lisfranc/chopart	55	4	20	33	0	2
Syme	7	0	0	6	0	1
Below-knee	242	15	104	109	1	28
Through-knee/above-knee	341	31	168	115	2	56
Hip	8	1	6	0	0	2
Total	1,703	80	618	895	5	185

a: Amputations not due to ischemia are not included.

ASO: arteriosclerosis obliterans; DM-ASO: diabetic ASO; TAO: thromboangitis obliterans (Buerger's disease).

Upper limb amputations remained stable this year; however, lower limb amputations continued to increase.

7) Arterial/venous graft harvesting, and surgical cannulation and removal for IABP, PCPS, and ECMO (Table 8-9)

Table 8-9 Arterial graft harvest, venous graft harvest, surgical cannulation and removal of IABP, PCPS, ECMO.

	Cases	30-day death
Arterial graft harvest	153	5
Venous graft harvest	238	6
Surgical cannulation and removal of IABP, PCPS, ECMO	1,660	483
Total	2,051	494

IABP: intraaortic balloon pumping; PCPS: percutaneous cardiopulmonary support; ECMO: extracorporeal membrane oxygenation.

Although the overall number of grafts increased compared to last year, the number of arterial and venous grafts decreased, and the future trend should be closely monitored.

Conclusion

One of the main purposes of participating in NCD is to utilize the data to improve the quality and safety of medical care. The Japanese Society for Vascular Surgery initiated a nationwide multicenter study in 2018 on treatment options for ruptured abdominal aortic aneurysms, comparing open surgery and EVAR. Enrollment was closed at the end of DEC 2021, and the paper is currently being prepared. One of the first attempts by the Japanese Society for Vascular Surgery to use NCD data involved a model research project. “A retrospective study on the treatment and prognosis of infected abdominal aortic and common iliac artery aneurysms” was published in the British Journal of Surgery in 2021,¹⁶⁾ and the Journal of Vascular Surgery in 2024,¹⁷⁾ while “a retrospective study on the surgical technique and prognosis of popliteal artery entrapment syndrome” was published in the European Journal of Vascular and Endovascular Surgery in 2023.¹⁸⁾ Furthermore, the Database Management and Administration Committee of the Japanese Society for Vascular Surgery plans to modify the databases on abdominal aortic aneurysms and acute occlusive arterial disease starting JAN 2024 and to substantially revise the database on chronic occlusive arterial disease from 2025 to make better use of NCD as a database. We are engaging in continuous discussions with the Japanese Committee for Stentgraft Management (JACSM) and the Japan Critical Limb Ischemia Database (JCLIMB) to create a more efficient, useful, and user-friendly database. We welcome your candid opinions and suggestions.

We sincerely hope that the vascular surgery NCD database will contribute to providing high-quality medical care to patients suffering from vascular diseases.

Acknowledgments

A great deal of effort went into the preparation of this annual report.

We would like to thank Ms. Chigusa Yamamoto of the Secretariat of the Japanese Society for Vascular Surgery, Ms. Kyoko Namatame and Ms. Momoka Shimada of the Secretariat of the NCD, and other persons for their great efforts devoted to preparation of this annual report.

Ethical Review

Data disclosure and analysis of vascular surgery data registered with the NCD are conducted on an opt-out basis. The Vascular Surgery Annual Report was approved by the NCD Ethics Committee on 10-OCT-2023 and by the Keio University School of Medicine Ethics Committee on 27-SEP-2024.

Annual Report 2019 Analysis Team

Members of the Database Management Committee of the Japanese Society for Vascular Surgery:

Hideaki Obara (chairperson), Yukio Obitsu (vice-chairperson), Akihiro Hosaka (vice-chairperson), Kunihiro Shigematsu, Shinsuke Mii, Hiroshi Banno, Noriyasu Morikage, Keisuke Miyake, Terutoshi Yamaoka, Kentaro Matsubara, Jin Okazaki, Kinya Matsui, Shinya Takase, Naoki Fujimura, Nobuyoshi Azuma (president of the Japanese Society for Vascular Surgery)

NCD Vascular Surgery Data Analysis Team:

Hiraku Kumamaru

Conflicts of Interest

All co-authors have no conflicts of interest.