Load independent impairment of reverse remodeling after valve replacement in hypertensive aortic stenosis patients

BACKGROUND

We evaluated the impact of hypertension on the left ventricular mass regression in aortic stenosis after aortic valve replacement.

METHODS

We prospectively studied 135 patients with severe aortic stenosis at baseline and 1 year after surgery. In 32 patients we analyzed myocardial gene expression of collagen types I and III, connective tissue growth factor, transforming growth factor-β1, metalloproteinase-2 and its tissue inhibitor and compared its levels vs controls.

RESULTS

Seventy-six patients (56.3%) had a history of hypertension. Hypertensive patients were older, had higher Euroscore-II and NYHA class, with no differences in stenosis severity. At 1 year follow-up there was a median decrease of mass index of 14.2% (P25-75: -4.3%-30.4%; p<0.001). Mass regression was significantly higher in patients without hypertension, with a median decrease of 25.9% (P25-75: 12.0%-38.7%) vs 5.4% (P25-75: -12.5%-20.1%; p=0.001), despite similar increase in effective orifice area and no differences in valvuloarterial impedance. After 1 year, higher baseline left ventricular mass index (p=0.005) and the absence of hypertension (p=0.002) or diabetes (p=0.041) were the only independent predictors of mass regression higher than the median. Comparing with controls, aortic stenosis patients had an increased expression of collagen types I and III, but only hypertensive patients had higher relative expression of collagen type I vs III. In hypertensive patients TIMP2 expression was up-regulated and correlated with higher baseline left ventricular mass index (r=0.61; p=0.020).

CONCLUSIONS

In aortic stenosis, hypertension impairs mass regression one year after valve replacement, independently of total afterload. Differences in the expression of extracellular matrix remodeling genes might contribute to this finding.