Metabolic risk factors in first acute coronary syndrome (MERIFACS) Study

Objectives: In acute coronary syndrome (ACS) patients the focus is on major conventional risk factors - CRF [diabetes, hypertension, elevated low-density cholesterol (LDL-C) and smoking] whereas others - specific metabolic risk factors - MRF [high-density lipoprotein cholesterol (HDL-C), body-mass index (BMI), waist-hip ratio (WHR), and triglycerides, and HbA1c get less attention. Methods: This is a prospective caseecontrol observational study from 15 tertiary care hospitals in India. CRF and MRF in patients presenting with first incidence of ACS (n ¼ 2153) were compared with matched controls (n ¼ 1210). Results: Propensity score matching (PSM) yielded 1193 cases and matched 1210 controls. Risk factor prevalence in cases vs. controls were CRF: hypertension - 39.4% vs 16.4% (p < 0.0001), diabetes - 42.6% vs 12.7% (p < 0.0001), smoking - 28.3% vs 9.3% (p < 0.0001) and elevated LDL-C - 70.2% vs 57.9% (p < 0.0001). MRF: High BMI - 54.7% vs 55.1% (p ¼ 0.84), increased waist: hip ratio 79.5% vs 63.6% (p < 0.0001), high HbA1c - 37.8% vs 14.9% (p < 0.0001), low HDL-C - 56.2% vs 42.8% (p < 0.0001) and elevated triglycerides - 49.7% vs 44.2% (p ¼ 0.007). Adjusted Odds ratios by multivariate analysis were CRF: hypertension - 2.3 (p < 0.001), diabetes - 4.7 (p < 0.001), high LDL-C - 3.3 (p < 0.001) and smoking6.3 (p < 0.001). MRF: High waist: hip ratio - 2.4 (p < 0.001) high HbA1c - 3.2 (p < 0.001), low HDL-C 2.2 (p < 0.001) and elevated triglycerides - 0.878 p ¼ 0.17. Conclusion: In India, the risk of ACS conferred by specific metabolic risk factors (High waist: hip ratio, Low HDL-C and High HbA1c) is comparable to that caused by CRF

Comparison of resting and adenosine-free pressure indices with adenosine-induced hyperemic fractional flow reserve in intermediate coronary lesions

Objective Fractional flow reserve (FFR) using adenosine has been the gold standard in the functional assessment of intermediate coronary stenoses in the catheterization laboratory. We aim to study the correlation of adenosine-free indices such as whole cycle Pd/Pa [the ratio of mean distal coronary pressure (Pd) to the mean pressure observed in the aorta (Pa)], instantaneous wave-free ratio (iFR), and contrast-induced submaximal hyperemia (cFFR) with FFR. Methods This multicenter, prospective, observational study included patients with stable angina or acute coronary syndrome (>48 h since onset) with discrete intermediate coronary lesions (40–70% diameter stenosis). All patients underwent assessment of whole cycle Pd/Pa, iFR, cFFR, and FFR. We then evaluated the correlation of these indices with FFR and assessed the diagnostic efficiencies of them against FFR ≤0.80. Results Of the 103 patients from three different centers, 83 lesions were included for analysis. The correlation coefficient (r value) of whole cycle Pd/Pa, iFR, and cFFR in relation to FFR were +0.84, +0.77, and +0.70 (all p values < 0.001), respectively, and the c-statistic against FFR ≤0.80 were 0.92 (0.86–0.98), 0.89(0.81–0.97), and 0.91 (0.85–0.97) (all p values < 0.001), respectively. The best cut-off values identified by receiver–operator characteristic curve for whole cycle Pd/Pa, iFR, and cFFR were 0.94, 0.90, and 0.88, respectively, for an FFR ≤0.80. By the concept of “adenosine-free zone” (iFR = 0.86–0.93), 59% lesions in this study would not require adenosine. Conclusion All the three adenosine-free indices had good correlation with FFR. There is no difference in the diagnostic accuracies among the indices in functional evaluation of discrete intermediate coronary stenoses. However, further validation is needed before adoption of adenosine-free pressure parameters into clinical practice.