To address the coronavirus (Covid-19) pandemic,¹ strict social containment measures have been adopted worldwide, and health care systems have been reorganized to cope with the enormous increase in the numbers of acutely ill patients.^2,3 During this same period, some changes in the pattern of hospital admissions for other conditions have been noted. The aim of the present analysis is to investigate the rate of hospital admissions for acute coronary syndrome (ACS) during the early days of the Covid-19 outbreak.

Aims: The aim of the present study was to establish the safety and efficacy profile of prasugrel and ticagrelor in real-life acute coronary syndrome (ACS) patients with renal dysfunction. Methods and results: All consecutive patients from RENAMI (REgistry of New Antiplatelets in patients with Myocardial Infarction) and BLEEMACS (Bleeding complications in a Multicenter registry of patients discharged with diagnosis of Acute Coronary Syndrome) registries were stratified according to estimated glomerular filtration rate (eGFR) lower or greater than 60 mL/min/1.73 m2. Death and myocardial infarction (MI) were the primary efficacy endpoints. Major bleedings (MBs), defined as Bleeding Academic Research Consortium bleeding types 3 to 5, constituted the safety endpoint. A total of 19 255 patients were enrolled. Mean age was 63 ± 12; 14 892 (77.3%) were males. A total of 2490 (12.9%) patients had chronic kidney disease (CKD), defined as eGFR <60 mL/min/1.73 m2. Mean follow-up was 13 ± 5 months. Mortality was significantly higher in CKD patients (9.4% vs. 2.6%, P < 0.0001), as well as the incidence of reinfarction (5.8% vs. 2.9%, P < 0.0001) and MB (5.7% vs. 3%, P < 0.0001). At Cox multivariable analysis, potent P2Y12 inhibitors significantly reduced the mortality rate [hazard ratio (HR) 0.82, 95% confidence interval (CI) 0.54–0.96; P = 0.006] and the risk of reinfarction (HR 0.53, 95% CI 0.30–0.95; P = 0.033) in CKD patients as compared to clopidogrel. The reduction of risk of reinfarction was confirmed in patients with preserved renal function. Potent P2Y12 inhibitors did not increase the risk of MB in CKD patients (HR 1.00, 95% CI 0.59–1.68; P = 0.985). Conclusion: In ACS patients with CKD, prasugrel and ticagrelor are associated with lower risk of death and recurrent MI without increasing the risk of MB.

Patient-specific computational fluid dynamics is a powerful tool for investigating the hemodynamic risk in coronary arteries. Proper setting of flow boundary conditions in computational hemodynamic models of coronary arteries is one of the sources of uncertainty weakening the findings of in silico experiments, in consequence of the challenging task of obtaining in vivo 3D flow measurements within the clinical framework. Accordingly, in this study we evaluated the influence of assumptions on inflow velocity profile shape on coronary artery hemodynamics. To do that, (1) ten left anterior descending coronary artery (LAD) geometries were reconstructed from clinical angiography, and (2) eleven velocity profiles with realistic 3D features such as eccentricity and differently shaped (single- and double-vortex) secondary flows were generated analytically and imposed as inflow boundary conditions. Wall shear stress and helicity-based descriptors obtained prescribing the commonly used parabolic velocity profile were compared with those obtained with the other velocity profiles. Our findings indicated that the imposition of idealized velocity profiles as inflow boundary condition is acceptable as long the results of the proximal vessel segment are not considered, in LAD coronary arteries. As a pragmatic rule of thumb, a conservative estimation of the length of influence of the shape of the inflow velocity profile on LAD local hemodynamics can be given by the theoretical entrance length for cylindrical conduits in laminar flow conditions.

Data regarding the best treatment for spontaneous coronary artery dissection (SCAD) are scarce. The aim of the present study was to compare the clinical outcomes of conservative versus invasive treatment in SCAD patients. We systematically searched the literature for studies evaluating the comparative efficacy and safety of invasive revascularization versus medical therapy for the treatment of SCAD from 1990 to 2020. The study endpoints were all-cause death, cardiovascular death, myocardial infarction, heart failure, SCAD recurrence and target vessel revascularization (TVR) rates. Random-effect meta-analysis was performed comparing the clinical outcomes between the two groups. A univariate meta-regression analysis was also performed. 24 observational studies with 1720 patients were included. After 28±14 months, a conservative approach was associated with lower TVR rate compared with invasive treatment (OR=0.50; 95%CI 0.28-0.90; P=0.02). No statistical difference was found regarding all-cause death (OR=0.81; 95%CI 0.31-2.08; P=0.66), cardiovascular death (OR=0.89; 95%CI 0.15-5.40; P=0.89), myocardial infarction (OR=0.95; 95%CI 0.50-1.81; P=0.87), heart failure (OR 0.96; 95%CI 0.41-2.22; P=0.92) and SCAD recurrence (OR=0.94; 95%CI 0.52-1.72; P=0.85). The meta-regression analysis suggested that male gender, diabetes mellitus, smoking habit, prior coronary artery disease, left main coronary artery involvement, lower ejection fraction and low TIMI flow at admission are related with higher overall mortality, whereas SCAD recurrence was higher among patients with fibromuscular dysplasia. A conservative approach was associated with similar clinical outcomes and lower TVR rates compared to with an invasive strategy in SCAD patients; future prospective studies are needed to confirm these results.