Impact of physiological and coronary artery disease risk factors on myocardial perfusion in stress computed tomography myocardial perfusion imaging

To analyze the correlation between the main perfusion parameters of the left ventricle and various physiological and coronary artery disease (CAD) risk factors or comorbidities using dynamic stress computed tomography myocardial perfusion imaging (CT-MPI) in patients without obstructive coronary stenosis. This retrospective analysis included 119 patients without obstructive coronary artery stenosis in computed tomography angiography (CTA), and without perfusion defects in CT-MPI. Patients were categorized into groups based on the presence or absence of physiological and CAD risk factors or comorbidities. The global myocardial blood flow (MBF), myocardial blood volume (MBV), and perfused capillary blood volume (PCBV) of the left ventricle were compared between groups, and correlations with continuous variables were analyzed. Multivariate linear regression was used to identify independent factors. Perfusion parameters were higher (MBF, 149.41 +/- 26.38 vs. 159.20 +/- 21.31 ml/100 ml/min, MBV, 17.09 +/- 2.37 vs.18.84 +/- 1.89, and PCBV, 9.82 +/- 2.21 vs. 11.47 +/- 1.79 ml/100 ml [all P < 0.05]) in female patients than in male patients. Hypertension and overweight/obesity resulted in lower perfusion parameters (hypertension vs. normotension: MBF, 148.09 +/- 21.15 vs. 161.47 +/- 25.13 ml/100 ml/min, PCBV, 10.25 +/- 2.23 vs. 11.22 +/- 1.96 ml/100 ml; overweight/obesity vs. none: MBF, 148.82 +/- 20.98 vs. 159.51 +/- 25.44 ml/100 ml/min, PCBV, 10.20 +/- 1.93 vs. 11.15 +/- 2.22 ml/100 ml [all P < 0.05]). Body surface area (BSA), body mass index, stress heart rate (HR), incremental HR, coronary total plaque volume, and stress systolic blood pressure were significantly correlated with perfusion parameters (all P < 0.05). Stress HR, BSA, and hypertension were independent predictors of MBF, stress HR and sex were independent predictors of MBV, and stress HR and BSA were independent predictors of PCBV. Dynamic stress CT-MPI myocardial perfusion is affected by stress HR, sex, and BSA, and can identify early perfusion distribution in hypertension and obesity/overweight.