Delayed Blood Pressure Recovery Ratio and Its Relation to Endothelial Function and Left Ventricular Diastolic Function in Prediabetics

BACKGROUND: Endothelial function plays a key role in determining the clinical manifestations of established atherosclerotic lesions and has shown to be associated with suppressed sympathetic tone. Abnormal heart rate recovery (HRR) and systolic blood pressure (SBP) response during recovery has been found to have diagnostic role for detecting cardiovascular risk. AIM: To investigate whether with abnormal HRR and delayed SBP recovery ratio after exercise could predict endothelial dysfunction in prediabetic subjects. METHODS: Ninety-two prediabetic patients underwent brachial artery flow-mediated dilatation (FMD) test and a maximal exercise stress test. Seventy-eight healthy subjects served as a control group. HRR at 1 minute (HRR1 ) and SBP recovery ratio (SBPRR3 ) was defined as the SBP at minute 3 of recovery divided by SBP at peak exercise. Left ventricular diastolic function was assessed utilizing both conventional and tissue Doppler echocardiography. RESULTS: Flow-mediated dilatation was significantly decreased in prediabetics versus controls (P < 0.0001). Isovolumetric relaxation time and E/E' were significantly increased in prediabetics (P < 0.01 and <0.001). Delayed SBPRR3 was significantly correlated with impaired endothelial function and (E/E') in prediabetics (r = 0.62, P < 0.001 and r = 0.56, P < 0.001, respectively). Stepwise linear regression analysis revealed that HRR1 and SBPRR3 were significant predictors of endothelial dysfunction (r = 0.61, r(2) = 0.37, P < 0.01 and r = 0.51; r(2) = 27; P < 0.0001). CONCLUSIONS: Abnormal HRR1 and delayed SBP response detected during recovery imply a significant correlation with impaired endothelial function and diastolic dysfunction in prediabetics.