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

ABSTRACT

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.