Left ventricular performance after aortic valve replacement in patients with low ejection fraction.

The operative validity of aortic valve replacement (AVR) for high-risk patients with impaired left ventricular (LV) function is controversial. We measured LV contractility, afterload, and efficiency by use of transthoracic echocardiography data obtained before, after, and approximately 1 year after isolated AVR for 335 patients with aortic stenosis (AS group; n = 160), aortic regurgitation (AR group; n = 116), or aortic stenosis and regurgitation (ASR group; n = 59). Two subgroups were created: LV ejection fraction (EF) of ≥50 % (normal-EF subgroup) and <50 % (low-EF subgroup). Contractility decreased after AVR in the normal-EF AS and normal-EF AR subgroups, but did not change after AVR in the low-EF subgroups. Afterload decreased after AVR in the AS group and increased in the AR group. LV efficiency was unchanged after AVR in the normal-EF AS and ASR subgroups, worsened in the normal-EF AR subgroup, improved in the low-EF AS and ASR subgroups, and did not improve in the low-EF AR subgroup. LV contractility and efficiency improved during the 1-year period after AVR for all patients and subgroups, but the improvements in the low-EF AR subgroup were not as good as those in the low-EF AS and ASR subgroups. Improvements in LV contractility and efficiency after AVR can be expected for patients with low EF. However, contractility and efficiency did not improve after AVR for patients with AR and low EF. Low mortality and morbidity of AVR likely conceal a latent problem among patients with AR.