LEFT-VENTRICULAR GEOMETRIC ADAPTATION TO CHRONIC PRESSURE-OVERLOAD - DIFFERENCES BETWEEN SYSTEMIC HYPERTENSION AND VALVULAR AORTIC-STENOSIS- AN ECHOCARDIOGRAPHIC STUDY

In patients with systemic hypertension, the adaptation of left ventric le to pressure overload may manifest with four geometric patterns on t he echocardiographic tracing, and each of them seems to reflect a diff erent hemodynamic profile and to have a different prognostic value. Th e aim of this study was to analyze how the left ventricle adapts to pr essure overload in a group of adult patients with valvular aortic sten osis, compared to a group of hypertensive subjects. Left ventricular ( LV) mass indexed for body surface area and relative wall thickness (2 x posterior wall thickness/LV end-diastolic diameter) were measured on M-mode echo in 100 patients with essential hypertension of different severities and 80 patients with isolated valvular aortic stenosis (mea n valve area by Doppler: 0.67 +/- 0.2 cm(2)). LV mass index was signif icantly higher in aortic stenosis compared to hypertensive patients (1 87 +/- 50 vs. 128 +/- 42 g/m(2); p < 0.001); mean wall thickness was a lso higher in the aortic stenosis group (13.6 +/- 2 vs. 11.3 +/- 2.2 m m; p < 0.01) while LV end-diastolic diameter and LV fractional shorten ing were similar in the two groups. Among hypertensive patients, LV ma ss and relative wall thickness were normal in 33%, whereas 22% had inc reased relative wall thickness with normal LV mass (concentric remodel ing), 32% had increased mass and increased relative wall thickness ('t ypical' concentric hypertrophy) and 13% had increased LV mass with nor mal relative wall thickness (eccentric hypertrophy). Among aortic sten osis patients, none had a normal LV anatomy, 11% showed a concentric r emodeling pattern, 69% a concentric hypertrophy and 20% an eccentric h ypertrophy. It is of interest that most aortic patients with eccentric hypertrophy (14 out of 16) had a clinical picture of severe congestiv e heart failure associated with a significant LV dilation with a marke d reduction of LV fractional shortening and more severe valve stenosis . In conclusion, compared to hypertensive patients, aortic stenosis pa tients show a larger LV hypertrophy probably indicating a higher hemod ynamic overload. Furthermore, other than with hypertension, the presen ce of eccentric hypertrophy in patients with aortic stenosis usually i ndicates a more severe disease. The evaluation of the geometric patter n of the left ventricle may add useful information to the clinical eva luation of patients with chronic pressure overload.