Study questions

What is the temporal course of reduced left ventricular ejection fraction (LVEF), its predictors, and impact on prognosis in severe aortic stenosis (AS)?

Methods

The investigators evaluated serial echocardiograms of 928 consecutive patients with a first-time diagnosis of severe AS (aortic valve area [AVA] ≤1 cm²) who had at least 1 echocardiogram before the diagnosis. A total of 3,684 echocardiograms (median three studies per patient) within the preceding 10 years were analyzed. The primary endpoint was defined as all-cause mortality. All patients were followed up until death or last contact, at which time they were censored.

Results

At the initial diagnosis, 196 (21%) patients had an LVEF <50% (35.1 ± 9.7%) and 732 (79%) had an LVEF ≥50% (64.2 ± 6.1%). LVEF deterioration had begun before AS became severe for those with an LVEF <50%, and accelerated after the AVA reached 1.2 cm², whereas mean LVEF remained >60% in patients with LVEF ≥50% at initial diagnosis. The strongest predictor for LVEF deterioration was LVEF <60% at 3 years before AS became severe (OR, 0.86; 95% CI, 0.83-0.89; p < 0.001). During a median follow-up of 3.3 years, mortality was significantly worse not only for patients with an LVEF <50%, but for patients with an LVEF of 50% ≤ LVEF <60% compared with patients with an LVEF ≥60% even after aortic valve replacement (p < 0.001).

Conclusions

The authors concluded that in patients with severe AS and reduced LVEF, a decline in LVEF began before AS became severe, and accelerated after the AVA reached 1.2 cm².

Perspective

This study suggests that LVEF <60% at the time of moderate AS predicts further deterioration of LVEF. It seems that there may be an underlying myocardial process predisposing this group of patients to developing LV maladaptation to increased LV afterload when AS severity is only moderate. Furthermore, among patients with severe AS and an LVEF <60%, clinical outcomes, including mortality, are worse even after AVR is performed. Additional studies are indicated to assess whether patients with moderate AS and an LVEF <60% can benefit from earlier AVR.