Relations of ambulatory blood pressure level and variability to left ventricular and arterial function and to left ventricular mass in normotensive and hypertensive adults
Diabetes Mellitus, Type 2
Hypertrophy, Left Ventricular
OBJECTIVE: To assess the relationships between the level and variability of ambulatory blood pressure and left ventricular and arterial function. METHOD: We related 24 h ambulatory systolic blood pressure (SBP) and diastolic blood pressure (DBP), measures of their variability and clinic blood pressures to echocardiographic measures of left ventricle geometry and systolic function, total peripheral resistance, and the pulse pressure: stroke volume ratio as a measure of arterial stiffness in 58 normotensive and 222 unmedicated hypertensive adults. RESULTS: For hypertensive patients and for the entire population, awake and home ambulatory as well as technician-measured DBP were negatively related to left ventricle midwall fractional shortening (MWS) and to MWS as a percentage of the value predicted for end-systolic stress (afterload-corrected MWS), with inconsistent relations with SBP. Similarly, the SD and coefficient of variation of awake ambulatory DBP, but not SBP, were negatively related to both measures of left ventricle midwall function. Hypertensive patients in the lowest quintile of afterload-corrected MWS had similar physician-measured but higher ambulatory awake and home as well as technician-measured DBP, but not SBP, and higher SD of awake SBP and DBP than did those with higher afterload-corrected MWS. Ambulatory awake, home, and sleep as well as technician-measured DBP, but not SBP, were positively related to total peripheral resistance at rest whereas all components of ambulatory SBP, but not DBP, were positively related to the resting p;ulse pressure: stroke index ratio, a measure of arterial stiffness. We detected no relation between the nocturnal dip in blood pressure and any measure of left ventricular or arterial function or left ventricle geometry. Finally, left ventricle mass and relative wall thickness were related most strongly to awake and home ambulatory SBP whereas left ventricular relative wall thickness was also related to the SD of awake DBP. CONCLUSION: For this population of predominantly hypertensive unmedicated adults, ambulatory blood pressures during waking hours and at home were related to left ventricular and arterial function, the strongest relations being negative ones of DBP with left ventricular midwall function and positive ones of ambulatory DBP with peripheral resistance and ambulatory SBP with a measure of arterial stiffness. For this population the nocturnal dip of blood pressure was not related to measures either of cardiovascular function or of left ventricular structure.