Repetitive restenosis in a biodegradable polymer sirolimus-eluting stent with hypersensitivity reaction: a case report

Stentless percutaneous coronary intervention with directional coronary atherectomy and drug-coated balloon angioplasty in worsening angina patients with metal allergies

Metal allergy is a concern in percutaneous coronary intervention (PCI) with stent implantation because of its potential association with poor cardiovascular outcomes, such as stent thrombosis and recurrent in-stent restenosis requiring revascularization. Although stentless PCI with drug-coated balloon (DCB) angioplasty is theoretically useful for patients with metal allergies, DCB angioplasty alone for huge plaques in large vessels may yield inadequate luminal enlargement and coronary deep dissection, leading to insufficient results. Directional coronary atherectomy (DCA) is effective to reduce plaque volume. However, the efficacy of DCA followed by DCB (DCA/DCB) angioplasty in patients with metal allergies has never been described. We present two cases wherein stentless PCI with DCA/DCB angioplasty was an alternative revascularization strategy for patients with metal allergy and concomitant worsening angina pectoris involving proximal left anterior descending artery stenoses. Preoperative evaluation using coronary computed tomography angiography in Case 1 and intravascular ultrasound in Case 2 was useful to determine the possible use of the DCA/DCB procedure for huge plaques in large vessels.

Learning objective

Revascularization for patients with metal allergy with worsening angina pectoris due to stenoses of the proximal main arteries is often challenging because of the necessity to avoid stent implantation. As stentless percutaneous coronary intervention (PCI) is theoretically useful in such settings, PCI with directional coronary atherectomy (DCA)/drug-coated balloon angioplasty can be one of the treatable strategies. Preoperative evaluation of plaque morphology for the suitability of DCA procedure is important.

Hypersensitivity and in-stent restenosis in coronary stent materials

Coronary heart disease (CHD) is a type of cardiovascular disease with the highest mortality rate worldwide. Percutaneous transluminal coronary intervention (PCI) is the most effective method for treating CHD. However, in-stent restenosis (ISR), a long-term complication after PCI, affects the prognosis of patients with CHD. Previous studies have suggested that hypersensitivity reactions induced by metallic components may be one of the reasons of this complication. With the emergence of first- and second-generation drug-eluting stents (DES), the efficacy and prognosis of patients with CHD have greatly improved, and the incidence of ISR has gradually decreased to less than 10%. Nevertheless, DES components have been reported to induce hypersensitivity reactions, either individually or synergistically, and cause local inflammation and neointima formation, leading to long-term adverse cardiovascular events. In this article, we described the relationship between ISR and hypersensitivity from different perspectives, including its possible pathogenesis, and discussed their potential influencing factors and clinical significance.

Histopathological findings of late-phase restenosis after directional coronary atherectomy with drug-coated balloon angioplasty: a case report

Background

Drug-coated balloon angioplasty after directional coronary atherectomy (DCA) allows for a stentless strategy providing good short-term outcomes; however, late-phase restenosis and its mechanism remain unclear. Moreover, histopathological evaluation for late-phase restenosis post-drug-coated balloon angioplasty after DCA has never been reported.

Case summary

We report the first case of late-phase restenosis post-drug-coated balloon angioplasty after DCA, wherein tissue analysis using intravascular coronary imaging and histopathology suggested neovascularization in newly developed neointimal proliferation. A 52-year-old man with a history of dyslipidaemia presented with exertional angina pectoris. He underwent percutaneous coronary intervention (PCI) with drug-coated balloon angioplasty after DCA for the proximal left anterior descending artery. Although coronary angiography after nine months revealed no restenosis, he experienced recurrent chest discomfort after 25 months. Coronary angiography confirmed late-phase restenosis, and intravascular ultrasound showed progressively developed neointima above the underlying residual plaque. Optical coherence tomography suggested developing neovascularization within the neointima. Stentless PCI with drug-coated balloon angioplasty after DCA was re-performed, and collected restenotic sample. The histopathological evaluation confirmed less-cellular neointimal proliferation with rich neovascularization and concomitant diffuse vascular endothelial growth factor (VEGF) expression.

Discussion

Late-phase restenosis post-drug-coated balloon angioplasty after DCA comprised less-cellular neointima, suggesting inhibition of cell proliferation by drug-coated balloon efficacy. However, diffuse VEGF expression and concomitant rich neovascularization with haemorrhage and inflammation might indicate neointimal proliferation. Further large-scale investigations of the restenotic mechanism should be performed to avoid long-term target vascular failure after drug-coated balloon angioplasty post-DCA.

Severe chronic aortic regurgitation after percutaneous coronary intervention: a case report and literature review

Background

Severe aortic regurgitation (AR) is an extremely rare complication after coronary catheterization and percutaneous coronary intervention (PCI), where most reported cases have required relatively urgent surgical intervention due to acute-onset AR and cardiac decompensation.

Case summary

We report a case of a 60-year-old woman that previously presented with a non-ST-elevation myocardial infarction (NSTEMI) due to an ostial right coronary artery stenosis. During the course of 2 years, she developed five recurrent NSTEMI due to in-stent thrombosis, necessitating either a new coronary stent or balloon. She developed a chronic severe AR due to a drug-eluting coronary stent protruding from the right coronary artery and underwent successful aortic valve replacement and coronary artery by-pass grafting.

Discussion

We performed a literature review and identified 16 reported cases of iatrogenic severe aortic regurgitation related to coronary catheterization or percutaneous coronary intervention. All patients developed an acute aortic regurgitation and, thus, we report the first case of a delayed complication caused by a protruding coronary stent. The surgical strategy is related to the extent of the damage, where smaller perforations or lacerations seems to be feasible for aortic valve repair and larger defects more often lead to aortic valve replacement. Our patient developed a fibrotic right coronary cusp which could not be used to perform a successful aortic valve repair.

Clinical outcome of biodegradable polymer sirolimus-eluting stent and durable polymer everolimus-eluting stent in patients with diabetes

Background

Diabetes mellitus is a risk for increased incidence of adverse clinical events after percutaneous coronary intervention. However, the difference in the incidence of adverse clinical events according to stent type in patients with diabetes remains to be elucidated. In the present study, we aimed to compare the clinical outcomes between patients treated with the biodegradable polymer sirolimus-eluting stents (BP-SES) and the durable polymer everolimus-eluting stents (DP-EES) among patients with diabetes.

Methods

Among 631 lesions in 510 consecutive patients treated with either BP-SES or DP-EES, 165 lesions in 141 patients with diabetes mellitus and stable angina pectoris were identified and classified into the BP-SES group (48 lesions in 44 patients) and the DP-EES group (117 lesions in 100 patients). The incidence of adverse clinical events after stent implantation was compared between the 2 groups.

Results

There was no significant difference in the prevalence of conventional risk factors, lesion characteristics, and procedural characteristics between the 2 groups. During median 386 [334–472] days follow-up, the incidence of target lesion revascularization (11.4 vs. 2.0%, p = 0.003) and device-oriented clinical endpoint (13.6 vs. 6.0%, p = 0.035) in the BP-SES group was significantly greater than that in the DP-EES group. A univariate model demonstrated that the BP-SES usage was significantly associated with the higher incidence of target lesion revascularization (odds ratio, 6.686; 95% confidence interval, 1.234–36.217; p = 0.028).

Conclusion

BP-SES was associated with the greater incidence of TLR than the DP-EES in patients with diabetes mellitus. Further studies with larger cohorts and longer follow-up are required to confirm the present results.