Abstract 13838: Tako-Tsubo Cardiomyopathy: Direct Evidences of Sympathetic Nervous System Hyperactivity
Tako-Tsubo Cardiomyopathy (TTC) is an acute reversible condition that involves left ventricular apical ‘ballooning’ and mimics acute myocardial infarction with no detectable coronary arterial disease. TTC typically affects aged postmenopausal women and is usually triggered by emotional or physical stress. The exact pathophysiology remains unknown but datas suggest a link between sympathetic hyperactivity (catecholamine plasmatic level, heart rate variability depressed) and TTC. Up to now, no direct evidence of sympathetic hyperactivity has been established. The aim of our study was to determine, by microneurography (direct technique), if patients with TTC present an increased of muscle sympathetic nerve activity (MSNA) in TTC patients in comparison to matched heart failure controls. We enrolled 13 TTC patients (80.1 ± 2.1 years, all female, Body Mass Index: 22.8 ± 0.9 kg/m², Left Ventricular Ejection Fraction: 40 ± 2%) and 13 control patients matched for age, sex, BMI, LVEF, renal function and hemoglobinemia. Between 36 hours after admission, all patients underwent a microneurography and an arterial baroreflex gain assessment (slope of the relationship between MSNA and diastolic blood pressure). There is no difference between groups on hemodynamics parameters (SBP, DBP, MBP and HR) and oxygen saturation. TTC patients presented a significant increase of sympathetic activity (66.3 ± 2.7 vs 55.6 ± 2.6 bursts/min; p=0.0088). Arterial baroreflex gain is significantly decreased compared to control patients (1.2 ± 0.3 vs. 2.5 ± 0.4 %MSNA/mmHg; p=0.005). This study showed for the first time with a direct technique, that TTC patients present a sympathetic hyperactivity. The increase of sympathetic nerve activity is associated to a decrease of arterial baroreflex gain.
- © 2011 by American Heart Association, Inc.