Quantitative myocardial perfusion should be interpreted in the light of sex and co-morbidities in patients with suspected chronic coronary syndrome - a cardiac positron emission tomography study.

Diagnosis and treatment of patients with suspected chronic coronary syndrome (CCS) currently relies on the degree of coronary artery stenosis and its significance for myocardial perfusion. However, myocardial perfusion can be affected by factors other than coronary stenosis. The aim of this study was to investigate to what extent sex, age, diabetes, hypertension and smoking affect quantitative myocardial perfusion, beyond the degree of coronary artery stenosis, in patients with suspected CCS. Eighty-six patients (median age 69 [range 46-86] years, 24 females) planned for elective coronary angiography due to suspected CCS were included. All patients underwent cardiac 13 N-NH 3 Positron Emission Tomography to quantify myocardial perfusion at rest and stress. Lowest myocardial perfusion (perfusion min ) at stress and rest and lowest myocardial perfusion reserve (MPR min ) for all vessel territories was used as dependent variables in a linear mixed model. Independent variables were vessel territory, degree of coronary artery stenosis (as a continuous variable of 0-100% stenosis), sex, age, diabetes, hypertension and smoking habits. Degree of coronary artery stenosis (P<0.001), male sex (1.8±0.6 vs 2.3±0.6 ml/min/g, P<0.001), increasing age (P=0.03), diabetes (1.6±0.5 vs 2.0±0.6 ml/min/g, P=0.02) and smoking (1.9±0.6 vs 2.1±0.6 ml/min/g, P=0.05) were independently associated with myocardial perfusion min at stress. Degree of coronary artery stenosis (P<0.001), age (P=0.05), diabetes (1.8±0.6 vs 2.3±0.7, P=0.05) and hypertension (2.2±0.7 vs 2.5±0.6, P=0.03) were independently associated with MPR min . Sex, increasing age, diabetes, hypertension and smoking affect myocardial perfusion independent of coronary artery stenosis in patients with suspected CCS. Thus, these factors need to be considered when assessing the significance of reduced quantitative myocardial perfusion of patients with suspected CCS. This article is protected by copyright. All rights reserved.