Similar effects of isolated systolic and combined hypertension on left ventricular geometry and function: the LIFE study

Echocardiograms of 143 patients with isolated systolic hypertension were compared to 808 patients with combined (systolic and diastolic) hypertension. All patients met electrocardiographic criteria for left ventricular hypertrophy and were evaluated off medication. Patients with isolated systolic hypertension were older, shorter, weighed less, and were mostly women, but body mass index (BMI) was similar in both groups. Systolic blood pressure (SBP) was 172 mm Hg in isolated systolic hypertension, 174 mm Hg in combined (P = not significant). Diastolic blood pressure was 83 and 101 mm Hg, respectively (P< .001). Despite having mean arterial pressure 12 mm Hg lower than patients with combined hypertension, the group with isolated systolic hypertension had equally severe abnormalities of left ventricular mass, left ventricular geometric patterns, and measures of systolic and diastolic function. Peripheral resistance was lower and pulse pressure/stroke volume ratio (arterial stiffness index) was higher and the isovolumic relaxation time shorter in isolated systolic hypertension. Multiple regression analyses identified age, height, BMI, stress-corrected mid wall shortening, stroke volume, male gender, and systolic or mean blood pressure (but not isolated systolic hypertension) as independent correlates of left ventricular mass. Relative wall thickness was independently associated with isolated systolic hypertension (P = .001) in addition to mean pressure and other covariates. The present results add support to the concept that systolic blood pressure (SBP) is a stronger determinant than diastolic pressure of cardiac target organ damage in hypertension.