The Outcome of Ultrathin-Strut Biodegradable Polymer-Coated Sirolimus-Eluting Stents in Coronary Artery Disease Patients – A Feasibility Study

BACKGROUND: Drug-eluting coronary stents with ultrathin struts and biodegradable polymers have been shown to reduce inflammation, neointimal proliferation, and thrombus formation, leading to less early and late complications in patients with coronary artery disease as compared to thinner strut and durable polymer second-generation stents. In Oman, currently, second-generation stents are used for all patients. OBJECTIVE: The purpose of this feasibility study was to evaluate the clinical safety and performance of ultrathin-strut (60 μm) biodegradable polymer-coated sirolimus-eluting stents in an all-comers patient population. METHODS: This was a prospective, observational, single-center, and single-arm investigator-initiated study from August 2018 to August 2019. Inclusion criteria: 18 years of age, patients with symptomatic coronary artery disease indicated for percutaneous coronary intervention, and stenting of at least one coronary lesion. All patients were followed clinically or telephonically at 12 months after the index procedure. RESULTS: A total of 88 patients were recruited in the study, but 10 patients were lost to follow-up and hence excluded from the analysis. The overall mean age was 63 ± 13 years and 78% were males. The main comorbid conditions were hypertension (58%), diabetes mellitus (49%), and hyperlipidemia (26%). Fifty-three percent presented with unstable angina or non-ST elevation myocardial infarction (MI), 10% with ST elevation MI, recent MI 16%, 18% with stable angina, and 1.3% in cardiogenic shock. The mean left ventricular ejection fraction of the cohort was 46 ± 14%. Angiographically, Type A lesions were seen in 25%, Type B in 32%, and Type C in 42%. Left anterior descending stenting was done in 44%, right coronary artery in 32%, left circumflex artery in 14%, left main in 5%, and graft stenting in 4%. Device success was 96%. Procedural success was seen in 97% of patients. At 1-year follow-up, 93% were asymptomatic; overall device-oriented clinical events were 6.8% including cardiac death in 2.7%, target-vessel MI in 2.7%, and target-lesion revascularization in 1.3% which all occurred in uncontrolled diabetic patients. CONCLUSIONS: At index admission and 1 year, ultrathin-strut biodegradable polymer-coated sirolimus-eluting stent study showed low device-related adverse clinical events which are comparable to published data for the second-generation stents. This feasibility study shows that these stents can be used in all types of stent-indicated patients with added advantages of biodegradable polymer and ultrathin struts. In addition, measures to prevent, diagnose, and control diabetes need to be taken in Oman as this cohort of patients develop ST after stenting.