Abstract
Although directional coronary atherectomy (DCA) is designed to effectively reduce plaque volume by debulking in patients with ischemic heart disease, excision of fibroatheroma has potential to cause distal embolization and periprocedural myocardial infarction. The patients had intravascular ultrasound-derived attenuated plaques in the culprit lesions. A DCA catheter was inserted over a filter-based embolic protection device. After DCA, filter no-reflow phenomenon occurred, and embolized debris was retrieved by the filter device. We describe the novel use of a filter-based embolic protection device during intravascular imaging-guided DCA, particularly in patients at high risk of distal embolization.
<Learning objective: The presence of intravascular ultrasound-derived attenuated plaques is at increased risk of distal embolization of debris and periprocedural myocardial infarction during directional atherectomy. A filter-based embolic protection device is available during intracoronary imaging-guided directional coronary atherectomy, particularly in patients at high risk of distal embolization.>
Keywords: Percutaneous coronary intervention, Atherectomy, Coronary artery disease
Introduction
The new 7-Fr guiding catheter-compatible directional coronary atherectomy (DCA) catheter AHTEROCUT (Nipro, Osaka, Japan) was developed to facilitate percutaneous excision of coronary plaques. However, excision of friable plaques has the potential to cause distal embolization, regardless of atherectomy device size and numbers of cuts during the procedure [1], [2]. On the other hand, it remains unclear whether the use of a distal embolic protection device can reduce the incidence of DCA-related myonecrosis in patients with fibroatheromatous plaques. We herein describe a novel use of the filter-based device to prevent distal embolization during DCA.
Case 1
A 71-year-old man with Canadian Cardiovascular Society class III symptoms who presented with worsening angina over 2 weeks was referred to the institute to undergo coronary angiogram. The coronary risk factors included dyslipidemia, obesity, and smoking. Coronary computed tomography (CT) angiogram revealed a left anterior descending (LAD) ostial stenosis with positive remodeling, low-attenuation plaque, and spotty calcification (Fig. 1). The circumflex artery and right coronary artery did not exhibit significant stenosis. We planned a left radial artery approach for cardiac catheterization, and then we used the 7-in-6-Fr Glidesheath Slender sheath (Terumo, Tokyo, Japan). The left coronary artery was engaged with a 7-Fr JCL35 SH guide catheter and crossed with a guidewire. Intravascular ultrasound (IVUS) OptiCross (Boston Scientific, Natick, MA, USA) demonstrated large plaque burden with attenuation and eccentric stenosis in the LAD ostium. Quantitative grayscale IVUS analysis was performed by QIvus version 3.0 (Medis, Leiden, the Netherlands). The minimum lumen area (MLA) was 1.87 mm2, plaque burden and the remodeling index at the MLA site were 91.0% and 1.07, respectively. The total atheroma volume and percent atheroma volume were 400.5 mm3 and 77.4%. A filter-based embolic protection device 5.0 mm Filtrap (Nipro) was advanced to the mid LAD. After attachment of an extension guidewire to the Filtrap device, a DCA catheter ATHEROCUT L (Nipro) was inserted in the proximal LAD. After we performed five cuts using the DCA catheter with 2 to 3 atm to remove plaques in the proximal LAD, subsequent angiogram revealed filter no-reflow phenomenon with the thrombolysis in myocardial infarction flow grade 0 in the LAD (Fig. 2). After aspiration proximal to the filter using a 7-Fr aspiration catheter, the LAD ostial lesion was then treated with a 3.5 × 20 mm drug-eluting stent. Coronary flow was restored to normal after retrieval of the filter device. Macroscopic material captured in the filter was identified. Final angiogram and IVUS revealed no residual stenosis in the proximal LAD, and final MLA and plaque burden were 8.40 mm2 and 65.6%, respectively. Cardiac enzymes were not raised (creatine kinase MB, 14 U/L), but cardiac troponin T was raised at 0.127 ng/mL (normal value <0.014 ng/mL) the next day. The patient remained asymptomatic at 1-year follow-up.
Fig. 1.
Case 1. Cardiac computed tomography, coronary angiogram, and intravascular ultrasound imaging.
LAD, left anterior descending artery; LCx, left circumflex artery; LM, left main.
Fig. 2.
Case 1. (A) Distal protection using the Filtrap device during directional coronary atherectomy (DCA). (B) Filter no-reflow phenomenon. (C) Intravascular ultrasound image after DCA followed by stent implantation. (D) Final angiogram.
LAD, left anterior descending artery.
Case 2
A 66-year-old man with diabetes, dyslipidemia, hypertension, and a history of colon cancer, who complained of new-onset chest discomfort during exercise, was diagnosed with effort angina. Coronary CT angiogram showed an eccentric stenosis in the proximal LAD. Using left radial access, the left coronary artery was engaged with a 7-Fr JCL35 guiding catheter. IVUS images demonstrated a proximal LAD stenosis with attenuated plaques and spotty calcification, and the MLA was 1.93 mm2 and plaque burden at the MLA site was 89.3%. DCA and drug-coated balloon treatment were planned instead of drug-eluting stent implantation, because he was at high risk for bleeding during antiplatelet therapy. Distal protection using 5.0-mm Filtrap was performed at the level of mid LAD. ATHEROCUT L (Nipro) was inserted over an extension guidewire attached to the Filtrap device and was positioned in the proximal LAD (Fig. 3). After five cuts for debulking with balloon inflation at 2 atm, filter no-reflow phenomenon occurred in the mid LAD. The Filtrap was removed due to detection of embolization into the filter, and then this resulted in complete resolution of no reflow without evidence of further embolization. After DCA, MLA and plaque burden at the MLA site were 6.55 mm2 and 58.0%. The proximal LAD was treated with a 3.5-mm cutting balloon followed by a 3.5 × 20 mm drug-coated balloon SeQuent Please (Nipro). No evidence of no-reflow, branch occlusion, or apparent dissection was seen on final angiogram and IVUS imaging. Atherectomy tissue specimens that were stored in the nosecone of the DCA catheter (Fig. 3G) as well as embolized material that were retrieved in the distal embolic protection device (Fig. 3H) were prepared for histopathologic analysis with ethanol preparation and hematoxylin/eosin staining. The next-day value of creatine kinase MB was 11 U/L and that of cardiac troponin T was 0.043 ng/mL. The patient was discharged home and remained symptom free at 1-year follow-up.
Fig. 3.
Case 2. (A) Coronary computed tomography. (B) Coronary angiogram before percutaneous coronary intervention. (C) The prevention of distal embolization using the Filtrap during directional coronary atherectomy (DCA). (D) Final angiogram after DCA followed by drug-coated balloon angioplasty. (E) IVUS image before DCA. (F) IVUS image after DCA. (G) Histological section of the plaques debulked by the DCA catheter, hematoxylin and eosin stained. Specimens contained tissue with granulomatous inflammation and fibrosis. Low amount of macrophage infiltration and microcalcification were also histopathologically found. (H) Histological section of embolized material in the filter. Hyalinized fibrous tissue was observed. There was no thrombus, and the captured material had neither calcification nor cholesterol crystal.
IVUS, intravascular ultrasound; LAD, left anterior descending artery.
Discussion
After assessment of lesion morphology by multimodality coronary imaging, we demonstrated the utility of distal protection device to prevent embolization of debris during DCA for lesions at high risk for no-reflow phenomenon and periprocedural myocardial infarction.
The occurrence of periprocedural myocardial infarction remains a barrier to DCA in ischemic heart disease. In the Coronary Angioplasty Versus Excisional Atherectomy Trial (CAVEAT-I), the incidence of periprocedural myocardial infarction was higher with DCA than with balloon angioplasty [2]. In the CAVEAT-II trial, DCA compared with balloon angioplasty in vein grafts was associated with a higher rate of angiographic success and greater acute lumen gain [3]. However, distal embolization occurred significantly more often with DCA than with balloon angioplasty, and there was a trend toward more non-Q wave myocardial infarction after DCA than after balloon angioplasty [4]. Waksman et al. also demonstrated that angiographic distal embolization was common in native coronary arteries and saphenous vein grafts after DCA, and that the length of hospital stay after percutaneous coronary intervention (PCI) was longer in patients with clinical distal embolization than without distal embolization [1]. Although early studies had raised concern about procedural complications such as embolization, acute occlusion, and perforation, some studies had a possibility that the risks of complications had not been adequately assessed in advance, because the use of intravascular imaging modalities had not been standardized.
Noninvasive imaging with coronary CT angiogram is a widespread method to evaluate coronary stenosis as well as coronary plaque characteristics. A prospective cohort study showed low-attenuation plaque was a strong prognostic marker for subsequent adverse cardiovascular events during a long-term follow-up period [5]. Furthermore, the presence of low CT attenuation plaque is likely to cause no-reflow phenomenon during PCI and then periprocedural myocardial infarction in patients with stable ischemic heart disease [6]. It also seems that IVUS has become increasingly important for quantitative and qualitative measurement of coronary arteries and for the decision of the PCI strategies. Deteriorated coronary blood flow during PCI frequently occurs in lesions with IVUS-derived attenuated plaques, which were commonly observed in patients with acute coronary syndrome [7]. In particular, IVUS use is the cornerstone for DCA, because IVUS imaging allows for evaluation of plaque distribution and morphology as well as the debulking effect.
Angelini et al. assessed characteristics of the debris captured by a filter device during stent implantation in de novo native coronary arteries of patients with stable or unstable angina [8]. The results of histopathological analysis showed the presence of platelets, leukocytes, red cells, fibrous tissue, calcium deposits, macrophages, or cholesterol clefts in the retrieved particles. Brilakis et al. showed platelet and fibrin thrombi were retrieved from distal protection devices during stent implantation in coronary lesions which contained lipid-rich plaques derived by near-infrared spectroscopy [9]. On the other hand, hyalinized fibrous tissue was captured from the Filtrap device during DCA. Incomplete retrieval of friable plaques by a nosecone was considered to contribute to distal embolization (Supplemental Video S1). However, we utilized distal protection device to prevent periprocedural myocardial necrosis (Supplemental Video S2). The distal protection devices have been used clinically in selected lesions with massive thrombus, large plaque burden, or attenuation especially in patients with acute coronary syndrome. A randomized controlled trial showed the use of the Filtrap device reduced the incidence of no-reflow in acute coronary syndrome patients who had IVUS-derived attenuation of ≥180° with a longitudinal length ≥5 mm in the culprit lesions [10]. Our novel technique has the potential to become a solution in treating lesions with lipid-rich plaques in the setting of DCA.
There are several limitations to this technique. First, embolization in side branches proximal to the filter might not be prevented. Second, there is concern about mechanical damage by the filter device distal to the culprit lesions when we insert a DCA catheter. However, the DCA catheter was safely delivered by our technique. The core shaft of the Filtrap device is made from stiff stainless steel, which allows the smooth delivery of a DCA catheter.
Conclusion
Although low-attenuation plaque is at high risk for periprocedural myonecrosis during DCA, distal protection with a filter-based embolic protection device was successfully utilized for prevention of distal embolization during DCA, and macroscopic embolized debris was captured in the filter device. Intravascular imaging assessment is highly recommended to facilitate DCA in stable or unstable ischemic heart disease.
Footnotes
Supplementary material related to this article can be found, in the online version, at doi:https://doi.org/10.1016/j.jccase.2020.02.006.
Appendix A. Supplementary data
The following are Supplementary data to this article:
References
- 1.Waksman R., Douglas J.S., Jr., Scott N.A., Ghazzal Z.M.B., Yee-Peterson J., King S.B., III Distal embolization is common after directional atherectomy in coronary arteries and saphenous vein grafts. Am Heart J. 1995;129:430–435. doi: 10.1016/0002-8703(95)90263-5. [DOI] [PubMed] [Google Scholar]
- 2.Harrington R.A., Lincoff M., Califf R.M., Holmes D.R., Jr., Berdan L.G., O’Hanesian M.A. Characteristics and consequences of myocardial infarction after percutaneous coronary intervention: insights from the coronary angiography versus excisional atherectomy trial (CAVEAT) J Am Coll Cardiol. 1995;25:1693–1699. doi: 10.1016/0735-1097(95)00091-h. [DOI] [PubMed] [Google Scholar]
- 3.Holmes D.R., Jr., Topol E.H., Califf R.M., Berdan L.G., Leya F., Berger P.B. A multicenter, randomized trial of coronary angioplasty versus directional atherectomy for patients with saphenous vein bypass graft lesions. Circulation. 1995;91:1966–1974. doi: 10.1161/01.cir.91.7.1966. [DOI] [PubMed] [Google Scholar]
- 4.Lefkovits J., Holmes D.R., Califf R.M., Safian R.D., Pieper K., Keeler G. Predictors and sequelae of distal embolization during saphenous vein graft intervention from the CAVEAT-II trial. Circulation. 1995;92:734–740. doi: 10.1161/01.cir.92.4.734. [DOI] [PubMed] [Google Scholar]
- 5.Feuchtner G., Kerber J., Burghard P., Dichtl W., Friedrich G., Bonaros N. The high-risk criteria low-attenuation plaque <60 HU and the napkin-ring sign are the most powerful predictors of MACE: a long-term follow-up study. Eur Heart J Cardiovasc Imaging. 2017;18:772–779. doi: 10.1093/ehjci/jew167. [DOI] [PubMed] [Google Scholar]
- 6.Uetani T., Amano T., Kunimura A., Kumagai S., Ando H., Yokoi K. The association between plaque characterization by CT angiography and post-procedural myocardial infarction in patients with elective stent implantation. J Am Coll Cardiol Img. 2010;3:19–28. doi: 10.1016/j.jcmg.2009.09.016. [DOI] [PubMed] [Google Scholar]
- 7.Lee S.Y., Mintz G.S., Kim S.Y., Hong Y.J., Kim S.W., Okabe T. Attenuated plaque detected by intravascular ultrasound: clinical, angiographic, and morphologic features and post-percutaneous coronary intervention complications in patients with acute coronary syndromes. J Am Coll Cardiol Interv. 2009;2:65–72. doi: 10.1016/j.jcin.2008.08.022. [DOI] [PubMed] [Google Scholar]
- 8.Angelini A., Rubartelli P., Mistrorigo F., Della Barbera M., Abbadessa F., Vischi M. Distal protection with a filter device during coronary stenting in patients with stable and unstable angina. Circulation. 2004;110:515–521. doi: 10.1161/01.CIR.0000137821.94074.EE. [DOI] [PubMed] [Google Scholar]
- 9.Brilakis E.S., Adbel-Karim A.R., Papayannis A.C., Michael T.T., Rangan B.V., Johnson J.L. Embolic protection device utilization during stenting of native coronary artery lesions with large lipid core plaques as detected by near-infrared spectroscopy. Catheter Cardiovasc Interv. 2012;80:1157–1162. doi: 10.1002/ccd.23507. [DOI] [PubMed] [Google Scholar]
- 10.Hibi K., Kozuma K., Sonoda S., Endo T., Tanaka H., Kyono H. A randomized study of distal filter protection versus conventional treatment during percutaneous coronary intervention in patients with attenuated plaque identified by intravascular ultrasound. J Am Coll Cardiol Interv. 2018;11:1545–1555. doi: 10.1016/j.jcin.2018.03.021. [DOI] [PubMed] [Google Scholar]
Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.