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

OBJECTIVE: 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). METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.