Clinical impact of left ventricular outflow tract obstruction in takotsubo cardiomyopathy

Abstract

Background: A hyperdynamic state of the basal left ventricle sometimes results in obstruction of the left ventricular outflow tract (LVOT). However, the prevalence, clinical presentation, and prognostic effect of LVOT obstruction in takotsubo cardiomyopathy (TC) have not been fully evaluated. Methods and Results: Among 933 consecutive patients who underwent emergency coronary angiography for suspected acute coronary syndrome, 35 patients (3.8%) were diagnosed as TC. The cumulative 3-year incidence of all-cause death, cardiac death, hospitalization for congestive heart failure (CHF), and recurrent TC was 24.2%, 0.0%, 6.5%, and 12.2%, respectively. Among 27 patients with information of a LVOT pressure gradient, LVOT obstruction was present in 9 (33%). The prevalence of moderate to severe mitral regurgitation (67% vs. 11%, P=0.003), CHF (78% vs. 28%, P=0.02), and hypotension (56% vs. 5.6%, P=0.008) was significantly higher in patients with LVOT obstruction than in those without. Nevertheless, the cumulative 3-year incidence of all-cause death was not significantly different between the 2 groups (49.2% vs. 23.0%, P=0.22) with no cardiac deaths in either group. Hospitalization for CHF and recurrent TC were significantly more frequent in patients with LVOT obstruction (25.0% vs. 0.0%, P=0.04, and 25.0% vs. 6.7%, P=0.02). Conclusions: In 35 consecutive patients with TC, those with significant LVOT obstruction (33%) had a more serious clinical presentation such as CHF and hypotension, but had similar 3-year mortality rate as compared with those without.