Real World Experience of a Biodegradable Polymer Sirolimus-Eluting Stent (Yukon Choice PC Elite) in Patients with Acute ST-Segment Elevation Myocardial Infarction Undergoing Primary Angioplasty: A Multicentric Observational Study (The Elite India Study)

Post market surveillance registry (PIONEER) of the Yukon Choice PC-Elite Coronary Stent System for percutaneous coronary intervention in Indian acute coronary syndrome population

AIM

The aim of this study was to assess the safety and efficacy profile of a newer generation biodegradable DES, the Yukon Choice PC Elite with a temperature controlling mechanism, in patients with acute coronary syndrome (ACS).

METHODS

This prospective multi-center study (PIONEER Registry) was conducted in an Indian ACS population, therefore providing data in real world clinical practice. Patients with ACS underwent DES implantation in de novo native-vessel coronary lesions with the Yukon Choice PC Elite biodegradable polymer DES and were followed up for a year.

RESULTS

A total 999 patients were evaluated. The majority of patients were male (79.2%). A total of 6.7% of the patients had a history of prior myocardial infarction (MI) and 2.7% of patients had a history of previous coronary artery bypass graft. The clinical presentations of the patients included: unstable angina pectoris (UA) (46.4%), ST-segment elevation MI (STEMI) (38.1%), and Non-ST-segment elevation MI (NSTEMI) (15.4%). Implantation of the device was successful in 99.9% of cases. The median stent length and stent size were 21.0 mm (Range: 8.0-40.0 mm) and 2.8 mm (Range 2.0-4.0 mm), respectively. Through to one-year clinical follow-up after percutaneous coronary intervention, all-cause death occurred in 4 of 999 patients (Crude Percentage: 0.4%). Cardiac death, MI, TLR, and stent thrombosis were occurred in 1 (0.1%), 8 (0.8%), 12 (1.2%) and 1 (0.1%) patients, respectively.

CONCLUSION

The results of this post marketing surveillance registry suggest favorable safety and efficacy outcomes associated with the Yukon Choice PC Elite biodegradable DES in a real world Indian ACS population.

Sirolimus Release from Biodegradable Polymers for Coronary Stent Application: A Review

Drug-eluting stents (DESs) are commonly used for the treatment of coronary artery disease. The evolution of the drug-eluting layer on the surface of the metal stent plays an important role in DES functionality. Here, the use of biodegradable polymers has emerged as an attractive strategy because it minimizes the occurrence of late thrombosis after stent implantation. Furthermore, understanding the drug-release behavior of DESs is also important for improving the safety and efficacy of stent treatments. Drug release from biodegradable polymers has attracted extensive research attention because biodegradable polymers with different properties show different drug-release behaviors. Molecular weight, composition, glass transition temperature, crystallinity, and the degradation rate are important properties affecting the behavior of polymers. Sirolimus is a conventional anti-proliferation drug and is the most widely used drug in DESs. Sirolimus-release behavior affects endothelialization and thrombosis formation after DES implantation. In this review, we focus on sirolimus release from biodegradable polymers, including synthetic and natural polymers widely used in the medical field. We hope this review will provide valuable up-to-date information on this subject and contribute to the further development of safe and efficient DESs.

Use of dabigatran for treatment of left ventricular thrombus: A tertiary care center experience

OBJECTIVES

Direct oral anticoagulants (DOACs) are now replacing vitamin K oral anticoagulants (VKAs) owing to superior efficacy, rapid action, less bleeding, wider therapeutic range,and fewer food and drug interactions.Unfortunately, the available data on the use of DOACs, particularly dabigatran, for treatment of left ventricular thrombus (LVT) issparse. We have hereby presented the largest study on use of dabigatran in LVT.

METHODS

Retrospective data of patients having LVT as diagnosed by transthoracic echocardiography (TTE) was screened. Patients on dabigatran were included in the study and follow up data of 6 months was obtained through medical records.

RESULTS

Of the 15 patients included in the study, the most frequent etiology was ischemic heart disease (67%), including 7 patients of STEMI (47%), followed by non-ischemic cardiomyopathy in 5 patients (33%). Only one patient, with STEMI, developed mild gastrointestinal bleeding at 3 months. Complete clot resolution was seen in 2 patients (13%) at first week of follow up and total 5 patients (33%) at the end of second week. The rate of clot resolution at 1 month, 3 months, and 6 months were 80%, 93% and 100%, respectively. The median duration required for complete clot resolution was 30 days (IQR=14-30).

CONCLUSION

Dabigatran appears to be safe, highly efficacious and results in rapid LV clot resolution. DOACs may be a suitable alternative to warfarin in treatment of LV thrombus. However, larger studies are required to validate this hypothesis.

Comparison of Contrast Enhanced Low-Dose Dobutamine Stress Echocardiography with 99mTc-Sestamibi Single-Photon Emission Computed Tomography in Assessment of Myocardial Viability

INTRODUCTION

Dobutamine stress echocardiography (DSE) and myocardial perfusion scan are the commonly used modalities to detect viable myocardium. DSE is comparatively cheaper and widely available but has a lower sensitivity.

AIM

We aimed to compare contrast-enhanced low-dose dobutamine echocardiography (LDDE) and gated 99mTc-sestamibi myocardial perfusion scan (MPS) for the degree of agreement in the detection of myocardial viability.

METHODS

We studied 850 left ventricular segments from 50 patients (42 men, mean age 55.5 years), with coronary artery disease and left ventricular systolic dysfunction (ejection fraction < 40%), using contrast-enhanced LDDE and 99mTc-Sestamibi gated SPECT. Segments were assessed for the presence of viability by both techniques and head to head comparisons were made.

RESULTS

Adequate visualisation increased from 80% in unenhanced segments to 96% in contrast-enhanced segments. Of the total 850 segments studied, 290 segments (34.1%) had abnormal contraction (dysfunctional). Among these, 138 were hypokinetic (16.2% of total), 144 were severely hypokinetic or akinetic (16.9% of total), and 8 segments were dyskinetic or aneurismal (0.9% of total). Among 151 segments considered viable by technetium, 137 (90.7%) showed contractile improvement with dobutamine; in contrast, only 8 of the 139 segments (5.7%) considered nonviable by technetium had a positive dobutamine response. The per cent of agreement between technetium uptake and a positive response to dobutamine was 78.6% with kappa = 0.63, suggestive of a substantial degree of agreement between the two modalities.

CONCLUSION

Use of contrast-enhanced LDDE significantly increased the adequate endocardial border visualisation. Furthermore, this study showed a strong degree of agreement between the modalities in the detection of viable segments. So, contrast-enhanced LDDE appears to be a safe and comparable alternative to MPS in myocardial viability assessment.