Artur Klecha

Mesh covered stent in ST-segment elevation myocardial infarction

AIMS The MGuard stent (bare metal stent wrapped externally with a polymer mesh sleeve) is designed to prevent distal embolisation by reducing thrombus and plaque fragments released during and post percutaneous coronary intervention (PCI). The aim of this study was to confirm the clinical feasibility, safety and performance of the MGuard stent during primary PCI for ST-segment elevation myocardial infarction (STEMI). METHODS AND RESULTS The present study was a multicentre, prospective, single arm study in which 60 patients with STEMI <12 hours were enrolled. Predilatation was performed in 61.7% of the cases and thrombus aspiration in 18.3%. In one (1.7%) patient the stent could not cross the lesion. Final TIMI grade 3 flow was observed in 90.0% of patients, with myocardial blush grade 3 in 73.3% of patients and complete (>70%) ST-segment resolution 60 minutes after PCI in 61.4% of patients. In 5.0% of cases distal embolisation occurred. The total major adverse cardiac events rate during the 6-month follow-up was 1.7%. CONCLUSIONS Based on this experience, the MGuard stent implantation in STEMI patients is safe and highly effective. A larger randomised trial is warranted to confirm the clinical endpoints.

Myocardial perfusion in hypertensive patients with normal coronary angiograms.

Background Pressure-induced left ventricular hypertrophy is one of the mechanisms responsible for an impaired coronary vasodilating capacity leading to myocardial ischemia and angina. The aim of the study was to investigate myocardial perfusion using cardiovascular magnetic resonance in patients with arterial hypertension and a history of chest pain and normal coronary angiography, and to estimate the influence of left ventricular hypertrophy on the parameters of myocardial perfusion. Methods The study included 102 patients (mean age 55.4 ± 7.7 years) with well controlled hypertension and 12 healthy volunteers. In 96 patients, myocardial first-pass perfusion cardiovascular magnetic resonance both at rest and during an infusion of adenosine 140 μg/kg/min was performed. Semiquantitative perfusion analysis was performed by using the upslope of myocardial signal enhancement to derive the myocardial perfusion index and the myocardial perfusion reserve index. The study group was divided according to the presence of left ventricular hypertrophy in the cardiovascular magnetic resonance examination: group with left ventricular hypertrophy (n = 40) and without left ventricular hypertrophy (n = 56). Results Independent of the presence of left ventricular hypertrophy, there were significant differences in baseline myocardial perfusion index between hypertensive patients and controls (0.13 ± 0.07 vs. 0.04 ± 0.01; P < 0.001), and in stress myocardial perfusion index (hypertensive patients 0.21 ± 0.10 vs. controls 0.09 ± 0.03; P < 0.001). In hypertensive patients, the myocardial perfusion reserve index was reduced in the mid and apical portions of the left ventricle (1.71 ± 1.1 vs. 2.52 ± 0.83; P < 0.02). There was no significant correlation of myocardial perfusion reserve index with left ventricular mass or hypertrophy. Conclusion In patients with mild or moderate hypertension and a history of chest pain with normal coronary angiography, there is regional myocardial perfusion reserve impairment that is independent of the presence of left ventricular hypertrophy and may be a reason for angina.

Long-term follow-up of mesh-covered stent implantation in patients with ST-segment elevation myocardial infarction

BACKGROUND The MGuard stent (a bare-metal stent wrapped externally in a polymer mesh sleeve) was introduced to reduce the risk of distal embolisation and no-reflow phenomenon during percutaneous coronary intervention (PCI) in thrombus containing lesions, including ST-segment elevation myocardial infarction (STEMI). However, data on the long-term performance of the MGuard stent is limited. AIM To assess the long-term safety and efficacy of MGuard stent implantation during primary PCI for STEMI. METHODS AND RESULTS In this multicentre study, a total of 60 patients with STEMI ≤12 h treated with the MGuard stent were enrolled. Angiographic success of PCI was achieved in 96.7%, with the final TIMI grade 3 flow in 90.0% of patients. At six months, the overall rate of major adverse cardiac and cerebrovascular events (MACCE; composite of cardiac death, nonfatal target vessel reinfarction, target lesion revascularisation, and stroke) was 1.7%. A long-term follow-up of the study was successfully performed in 57 patients (mean follow-up of 38.7 ± 3.1 months). The long-term cardiac mortality was 7.0%, with a MACCE rate of 8.8%. There was no decrease in the left ventricular ejection fraction and no enlargement of the left ventriclebetween index and long-term follow-up echocardiogram. CONCLUSIONS The early safety and efficacy of the MGuard stent was maintained during the long-term follow-up. However, comparative data from ongoing randomised clinical trials are still required to confirm the long-term efficacy of MGuard stent implantation in patients with STEMI.

A clinical evaluation of the ProNOVA XR polymer-free sirolimus eluting coronary stent system in the treatment of patients with de novo coronary artery lesions (EURONOVA XR I study)☆

AIMS Evaluation of safety and efficacy of ProNOVA XR, a new generation of polymer-free sirolimus eluting stents (SES), utilizing a pharmaceutical excipient for timed release of sirolimus from the XR platform. METHODS AND RESULTS Safety and efficacy of ProNOVA XR coronary stent system was examined in EURONOVA prospective, single arm, multi-center registry of 50 patients with de novo native coronary lesions up to 28 mm in length in arteries between 2.25 and 4 mm. At 6-month, in-stent late lumen loss by QCA was 0.45 ± 0.41 mm and in-stent neointimal volume obstruction in the IVUS sub-study was 14 ± 11%. One-year clinical follow-up revealed a favorable safety profile, with 2% of in-hospital MACE and 6.4% of MACE from hospital discharge up to 12 months (including 1 cardiac death >30 days after stent implantation and 2 TLRs). According to the ARC definition, there was no definite or probable stent thrombosis and 1 possible stent thrombosis (2%) up to 12 months of clinical follow-up. CONCLUSIONS In this preliminary evaluation, ProNOVA XR polymer-free sirolimus eluting stent system appeared safe with an early promise of adequate effectiveness in the treatment of de novo coronary lesions in up to 12 months of clinical, angiographic and IVUS follow-up.

Association of coronary atherosclerosis with insulin resistance in patients with impaired glucose tolerance.

Objectives — The purpose of the study was to evaluate the role of insulin resistance (IR) in the development of coronary atherosclerosis in patients with impaired glucose tolerance. Methods and results — The study group consisted of 42 patients with impaired glucose tolerance. Based upon coronary angiography the patients were divided into group A – with prior myocardial infarction and critical coronary stenosis (n = 20) and group B – without prior myocardial infarction and without critical coronary stenosis (n = 22). In each patient glucose disposal rate (GDR) during metabolic clamp, insulinaemia in the fasting state and during the clamp, glycaemia during oral glucose tolerance test (OGTT), BMI and body mass composition were measured.The groups did not differ in age, BMI, percent fat content and distribution, and blood pressure. Fasting insulinaemia (56.7 mU/ml) was higher in group A than in group B (22.3 μU/ml). GDR in group A (2.96 mg/kg b.m./min) was lower than in group B (5.36 mg/kg b.m./min).There was a negative correlation between the number of critically narrowed coronary vessels and GDR in group A. GDR below 3.97 mg/kg b.m./min was found, based on regression analysis, to be a powerful risk factor for myocardial infarction. Conclusions — The relationship between IR and severity of coronary atherosclerosis implies its unfavourable role in the development of atherosclerosis. The present findings indicate a negative role of IR in the development of myocardial infarction and suggest that it is an independent risk factor, which identifies high-risk patients requiring treatment that would increase tissue insulin sensitivity.