Objective: In some patients with aortic stenosis left-ventricular hypertrophy exceeds what is needed to sustain the hemodynamic load imposed by the aortic stenosis, a condition named inappropriately high left-ventricular mass (iLVM). Although iLVM is associated with increased mortality after aortic valve replacement, prevalence and covariates of iLVM in asymptomatic aortic stenosis are unknown.
Methods: We analyzed baseline data from 1614 patients (67 ± 10 years, 51% hypertensive) recruited in the Simvastatin Ezetimibe in Aortic Stenosis study evaluating placebo-controlled combined simvastatin and ezetimibe treatment in asymptomatic mild-moderate aortic stenosis. iLVM was diagnosed by Doppler echocardiography as LVM greater than 28% of the expected LVM predicted from height, sex and stroke work.
Results: iLVM was detected in 268 patients (16.6%), irrespective of concomitant hypertension. Patients with iLVM had higher body weight, LVM and relative wall thickness, higher prevalence of systolic dysfunction (88 vs. 15%) and lower left-ventricular afterload (all P < 0.01) than patients with appropriate LVM in spite of comparable aortic stenosis severity. In multivariate analysis, all these five variables were independently associated with iLVM. The simple coexistence of low stress-corrected midwall shortening and left-ventricular hypertrophy was the best clinical model describing iLVM phenotype (sensitivity 72%, specificity 96%, area under the receiver operating characteristic curve 0.954).
Conclusion: iLVM is common in asymptomatic mild-moderate aortic stenosis and unrelated to severity of aortic stenosis or presence of hypertension. iLVM was associated with combined concentric geometry and reduced left-ventricular myocardial contractility, suggesting iLVM in asymptomatic aortic stenosis as a marker of more advanced myocardial disease.