Table 1.
Summary of studies
| Author (year) and study type | Study period | Patients | Aortic disease (%) | FET stent‐graft length | CSF drain? | Treatment outcomes | Adverse effects | Limitations/Downs and Black Quality Assessment score |
|---|---|---|---|---|---|---|---|---|
| Leontyev (2013) | 1/2003‐12/2011 | CET: 125 | Aneurysm: | Stent‐graft sized according to the dimension of the native nondiseased aorta or true aortic lumen in patients with acute or chronic dissection, with 5%–10% oversizing | Yes for all FET cases (could not confirm first 20 FET cases, confirmed use in all others) | In‐hospital mortality was 21.6% versus 8.7% for CET and FET patients, respectively (p = .1) | Stroke occurred in 16% versus 13% of CET versus FET patients (p = .4) | Limitations: Retrospective, nonrandomized, single center study; patients with heterogenous aortic pathology |
| CET: 42 (33.6) | ||||||||
| Spinal cord injury was significantly higher in the FET group (21.7% vs. 4.0%, p < .001) | ||||||||
| D&B score: 20 | ||||||||
| FET: 27 (58.7) | Estimated 1‐,3‐, and 5‐year survival were 70 ± 4%, 70 ± 4%, and 68 ± 4% (CET) and 74 ± 7%, 60 ± 9%, and 40 ± 1% (FET) | |||||||
| Renal failure occurred in 184% versus 23.9% of CET versus FET pts (p = .4) | ||||||||
| Acute type A: | ||||||||
| CET: 67 (53.6) | ||||||||
| FET:8 (17.4) | ||||||||
| Acute type B: | ||||||||
| FET: 46 | CET: 6 (4.8) | |||||||
| FET: 7 (16.2) | ||||||||
| Chronic type A: | ||||||||
| CET:3 (2.4) | ||||||||
| FET: 1 (2.2) | ||||||||
| Chronic type B: | ||||||||
| CET: 2 (1.6) | ||||||||
| RCS | FET: 1 (2.2) | |||||||
| DiEusanio (2014) | 2003‐2011 | CET: 36 | Reoperation: | Not reported | No | No significant difference was found for in‐hospital mortality (13.9% vs. 4.8% for CET and FET patients, respectively (p = .2)) | No significant difference was found for permanent neurologic dysfunction (elephant trunk: 5.7% vs. 9.5% for CET and FET (p = .4)) or paraplegia (2.9% vs. 4.8% for CET and FET, respectively (p = .6)) | Limitations: Retrospective, nonrandomized, small sample size; patients with heterogenous aortic pathology |
| CET: 4 (11.1) | ||||||||
| FET: 6 (28.6) | ||||||||
| D&B score: 19 | ||||||||
| Urgent/emergent: | ||||||||
| Endovascular second‐stage procedures were successfully performed in all FET patients with residual aneurysmal disease (n = 3); 9/11 CET patients with second‐stage procedures required conventional surgical replacement through lateral thoracotomy | ||||||||
| CET: 11 (30.6) | ||||||||
| FET: 3 (14.3) | ||||||||
| FET: 21 | ||||||||
| RCS | ||||||||
| Kaplan–Meier estimate of 4‐year survival was 75.8 ± 7.6 and 72.8 ± 10.6 in CET and FET patients, respectively (log‐rank p = .8) | ||||||||
| Shrestha (2015) | 8/2001‐3/2013 | CET: 97 | Aneurysm: | Stent‐graft length was chosen depending on the distance of the landing zone from the left subclavian artery | Yes for all FET cases; performed in CET cases “according to anatomic needs” | In‐hospital mortality was 24.7% versus 12.2% for CET and FET, respectively | Postoperative stroke rate was 12.4% versus 13.3% for CET and FET, respectively | Limitations: Retrospective, nonrandomized, single center study; heterogenous aortic pathology |
| CET: 43 (44) | ||||||||
| FET: 62 (34) | ||||||||
| D&B score: 19 | ||||||||
| During follow‐up, 27.8% of CET cases underwent a second‐stage procedure vs 27.7% in FET group | ||||||||
| Acute dissection: | ||||||||
| CET: 47 (48) | ||||||||
| FET: 67 (37) | ||||||||
| Chronic dissection: CET: 7 (7) | ||||||||
| FET: 180 | ||||||||
| FET: 51 (28) | ||||||||
| Reoperation: | ||||||||
| CET: 20 (21) | ||||||||
| FET: 54 (30) | ||||||||
| RCS | ||||||||
| Mkalaluh (2018) | 2001‐2017 | CET: 25 | Aneurysm: | Not reported | Not reported | In‐hospital mortality was statistically similar: 32% versus 20% for CET and FET, respectively (p = .52) | No significant difference between the incidence of stroke, acute renal failure or postoperative bleeding between CET and FET | Limitations: Retrospective, nonrandomized, single‐center study; small sample size |
| CET: 16 (64) | ||||||||
| FET: 12 (48) | D&B score: 20 | |||||||
| Dissection: | One‐year survival rates were higher with FET vs CET (60% vs. 38%), but not statistically significant | |||||||
| CET: 13 (52) | ||||||||
| FET: 15 (60) | ||||||||
| FET: 25 | ||||||||
| CCS | ||||||||
| Furitachi (2019) | 1/2010‐8/2018 | CET: 30 | Acute type A dissection: | Length selected by measuring the distance along an aortic centerline from the left carotid artery and the left subclavian artery to the descending aorta at the level of T4–6 | Not reported | No significant different was found for perioperative (30‐day) mortality between FET and CET patients (10% vs. 5%, respectively (p = .64)) | 6.7% of patients in the CET group experienced recurrent nerve palsy, and 6.7% of pts experienced paraplegia, whereas no patients in the FET group experienced either recurrent nerve palsy or paraplegia | Limitations: Retrospective, nonrandomized, single‐center study; small sample size |
| CET: 30 (100) | ||||||||
| D&B score: 18 | ||||||||
| FET: 20 (100) | ||||||||
| FET: 20 | ||||||||
| RCS | ||||||||
| 6.7% of pts in the CET group experienced a cerebrovascular event, while no patients in the FET group experienced an event | ||||||||
| Graft diameter was selected to be 90% of the outer aortic diameter at the level of the distal landing zone | ||||||||
| Stent‐graft induced new entry occurred in 15.8% of FET cases, with no cases in the CET group |
Abbreviations: CCS, case‐control matching study; CET, conventional elephant trunk; CSF, cerebrospinal fluid; D&B, Downs and Black; FET, frozen elephant trunk; RCS, retrospective cohort study.