Abstract 2809: Hypertension plays an important role on the Impairment of Myocardial Perfusion Reserve Determined by Quantitative Analysis of Myocardial Perfusion MRI
Background: Myocardial perfusion reserve (MPR) is associated with endothelial function, which has been shown to be influenced by hypertension, diabetes, dyslipidemia, renal dysfunction, anemia and left ventricular hypertrophy. Quantitative analysis of myocardial perfusion MRI can provide noninvasive assessment of MPR. The purpose of this study was to examine the influences of hypertension, diabetes, dyslipidemia, estimate glomerular filtration rate (e-GFR), left ventricular mass index (LVMI) and hematocrit on MPR in subjects without regional myocardial ischemia.
Method: We studied 123 patients (65 years ±10, male 67%, hypertension 76%, diabetes mellitus 44%, dyslipidemia 65%) who did not exhibit regional myocardial ischemia. ATP stress and rest first pass perfusion MR images were acquired in 1.5-T MR system, and MPR was calculated as the ratio of stress to rest myocardial blood flow (MBF).
Results: The rest MBF averaged in 123 patients was 1.14±0.84ml/min/g, and stress MBF was 3.15±2.00ml/min/g, and MPR was 3.24±1.86. Both rest and stress MBF were lower in men than in women. Rest MBF was significantly correlated with LVMI and hematocrit, and stress MBF showed significantly relation with hypertension, e-GFR and LVMI. Although there was no significant difference in rest MBF, stress MBF was significantly reduced in subjects with hypertension and those with lower e-GFR. MPR was associated with hypertension, e-GFR, LVMI and hematocrit. In multiple regression analysis, hypertension (p<0.01) showed strong correlation with MPR after adjusting age and gender when compared to other parameters such as diabetes (p=0.957), dyslipidemia (p=0.934), e-GFR (p=0.929), LVMI (p<0.05) and hematocrit (p=0.193).
Conclusion: Hypertension is the most important affecter of MPR in subjects without myocardial ischemia.