Prognostic impact of impaired left ventricular midwall function during progression of aortic stenosis.

Abstract

In hypertension, indexes of midwall left ventricular (LV) function may identify patients at higher cardiovascular (CV) risk independent of normal LV ejection fraction (EF). We analyzed the association of baseline and new-onset LV midwall dysfunction with CV outcome in a large population of patients with asymptomatic aortic stenosis (AS). One thousand four hundred seventy-eight patients with asymptomatic AS and normal EF (≥50%) at baseline in the Simvastatin Ezetimibe in Aortic Stenosis (SEAS) study were followed for a median of 4.3 years. LV systolic function was assessed by biplane EF and midwall shortening (MWS, low if <14% in men/16% in women) at baseline and annual echocardiographic examinations. One hundred twenty-three CV deaths and heart failure hospitalizations occurred during follow-up. In Cox analyses, adjusting for age, gender, body mass index, hypertension, EF, AS severity, LV hypertrophy and systemic arterial compliance, low baseline MWS predicted 61% higher risk of a major CV event and a twofold higher risk of death and heart failure hospitalization (P < .05). New-onset low MWS developed in 574 patients, particularly in elderly women with higher blood pressure and more severe AS (P < .05). In time-varying Cox analysis, new-onset low MWS was associated with a twofold higher risk of CV death and heart failure hospitalization, independent of changes over time in EF, AS severity, LV hypertrophy and systemic arterial compliance (P < .05). Low MWS develops in a large proportion of patients with AS and normal EF during valve disease progression and is a marker of increased CV risk.