Prevalence and characteristics of left ventricular outflow tract obstruction in Tako-Tsubo syndrome

Background and Objective Tako-Tsubo syndrome is a clinical entity mimicking acute coronary syndrome (ACS). Left ventricular outflow tract (LVOT) obstruction may occur in Tako-Tsubo syndrome. The aim of this study was to determine the prevalence and features of LVOT obstruction in Tako-Tsubo syndrome in a population presenting with ACS. Methods This study included consecutive patients admitted to 2 catheterization laboratories for suspected ACS. All patients underwent echocardiography, coronary arteriography, and left ventricular angiography if no significant coronary lesions were found. Results Among 10,366 patients referred for coronary angiography, the study population consisted of 3,909 patients with suspected ACS. Thirty-two patients (mean age 71 ± 13 years old) presented with Tako-Tsubo syndrome, resulting in a prevalence of 0.8% in our population of ACS and 5% of patients without significant coronary lesions. Eight women (mean age 81 ± 4 years old, P = .01) exhibited LVOT obstruction, a prevalence of 25% among Tako-Tsubo syndrome cases. All patients with intraventricular pressure gradient had systolic anterior motion of the mitral valve and septal bulge. Prevalence of septal bulge was 100% in patients with Tako-Tsubo syndrome and LVOT obstruction versus 29% in patients without LVOT obstruction ( P = .002). Mean degree of mitral regurgitation was 2.1 ± 0.7 in cases of LVOT obstruction versus 0.9 ± 0.7 in patients without LVOT ( P = .0003) and significantly decreased during follow-up (1 ± 0.8, P = .002). Recovery of left ventricular ejection fraction was similar in patients with and without LVOT obstruction ( P = .58). Conclusions The present study demonstrates that the prevalence of LVOT obstruction in Tako-Tsubo syndrome is high, with specific characteristics as compared with patients without LVOT obstruction. Echocardiography should be systematically performed for all patients presenting with Tako-Tsubo syndrome for the detection of LVOT obstruction.