2013 European Interventional Cardiology Annual Meeting Highlights
Although the weather in Paris in May was warm at first, cardiovascular interventionalists from all over the world gathered in the romantic capital for the annual European Society of Percutaneous Cardiovascular Interventions, where the latest advances in cardiovascular interventions and medical device advances were shared for lively discussions, bringing a wealth of information to the attending scholars. Highlights of this meeting included interventional treatment of structural heart disease, coronary interventions Biodegradable stents and polymer degradable drug-eluting stents are one of the highlights in coronary interventions. Gao Lijian, Department of Cardiovascular Medicine, Fu Wai Hospital, Beijing, China
The BIOFLOW II study is a comparison of the safety and efficacy of a fully degradable polymeric rapamycin drug-eluting stent (ORSIROTM) with a polymeric non-degradable drug-eluting stent (XIENCE PRIMETM). BIOFLOW-II is a prospective, international, multicenter, randomized clinical trial with a primary endpoint of late lumen loss (LLL) at 9 months. Secondary endpoints include target lesion failure rate (TLF), including cardiac mortality, target vessel Q-wave or non-Q-wave myocardial infarction rate (MI), coronary artery bypass grafting rate (CABG), and clinically driven target lesion revascularization rate (TLR ). Coronary angiography, intravascular ultrasound (IVUS), and optical coherence tomography (OCT) imaging were completed at 9 months.
A total of 452 patients were enrolled in the BIOFLOW-II study in Europe and were divided into the Orsiro stent group and the XIENCE PRIMETM stent group. 9-month LLL was 0.10±0.32 mm and 0.11±0.29 mm, respectively (non-inferiority p<0.0001). The rates of target lesion failure, cardiac mortality, target vessel Q-wave or non-Q-wave myocardial infarction, and target lesion revascularization were 4.8% and 5.3%, 0.7% and 0, 2.4% and 2.6%, and 2.1% and 2.7%, respectively), which were not statistically different. There was no in-stent thrombosis in either group. oCT showed better strut coverage in the Orsiro group than in the XIENCE PRIME group (98.3% versus 97.5%, p=0.042). the results of the BIOFLOW-II study demonstrated the effectiveness of this drug-eluting stent of bioresorbable polymer, while the low rate of myocardial infarction and revascularization and the absence of in-stent thrombosis proved its usefulness in safety in the treatment of in situ lesions (excluding triple branch lesions, chronic totally occlusive lesions, bifurcation lesions, open lesions, bridge vessel lesions, acute myocardial infarction, calcified lesions, and ejection fraction <30%).
BIOFLOW-III is an international multicenter, unblinded registry trial of 1356 patients placed with Orsiro stents with the primary endpoints of 12-month TLF including cardiac mortality, target vessel Q-wave or non-Q-wave myocardial infarction rate (MI), emergency coronary artery bypass graft rate (CABG), and clinically driven target lesion revascularization rate. Patients enrolled included: diabetes, small vessels (≤2.75 mm), chronic total occlusive lesions (CTO), and acute myocardial infarction (AMI). 12-month TLF was 4.7%. Cardiac mortality was 1.3%, target vessel Q-wave or non-Q-wave myocardial infarction rate was 2.0%, emergency coronary artery bypass graft rate was 0.0%, and clinically driven target lesion revascularization rate was 2.7%, confirming the efficacy and safety of Orsiro for use in more complex patients.
Drug-eluting bioresorbable stents may theoretically be the most ideal option, and the DESolve NX study enrolled 126 patients with single-branch coronary lesions, with the primary endpoint of late in-stent lumen loss at 6 months, and a 6-month QCA analysis of MLD of 2.41 ± 0.19 mm; diameter stenosis (DS) of 12.9 ± 11.2%; and LLL of 0.21 mm in both diabetic and non-diabetic patients. was 0.21 mm. intrasegmental restenosis was 3.5%. on IVUS analysis, vessel area increased from 10.44 mm2 to 12.23 mm2 postoperatively, an increase of 16.8% (P≤0.001). The mean lumen area increased by 9.0% (P≤0.001). no late acquired malapposition or aneurysm was detected by IVUS. oCT analysis showed a mean stent area increase of 16.9% (P≤0.001). Endothelial coverage was as high as 98.78±1.69% at 6 months, with a mean intimal hyperplasia thickness of 0.10±0.03 mm. OCT also did not reveal late acquired malapposition, with 1 sudden cardiac death (0.8%), 1 target vessel MI (0.8%), and 2 clinically driven TLRs (both PCI; 1.6%) at 6-month follow-up, and the incidence of MACE was 3.25% with no definite in-stent thrombosis. In addition, the BIOSOLVE-I (DREAMS stent) study provided preliminary confirmation of the efficacy and safety of the DREAMS drug-eluting bioresorbable stent. data from the ABSORB EXTEND (the earliest biodegradable stent) study showed that with the Absorb stent in 450 patients with more complex lesions than the ABSORB trial population, the 1-year major adverse cardiac events were slightly lower than the best metal drug-eluting stents. Among the diabetic subgroup analysis, the rate of major adverse cardiac events was found to be similar in diabetic patients versus non-diabetic patients.
In summary, both biodegradable stents and polymeric degradable drug-eluting stents have come a long way from first- and second-generation drug-eluting stents, especially with regard to late thrombosis and the dual antiplatelet time window for drug-eluting stents, and as clinical trial data continue to be updated, better entry points will be found that will benefit more patients.