Abstract 14416: Can a Simple ECG Marker Differentiate Takotsubo Cardiomyopathy From Ischemic Cardiomyopathy Due to Left Anterior Descending Coronary Artery Disease?
Background: Takotsubo cardiomyopathy (TCM) as well as ischemic cardiomyopathy due to significant Left Anterior Descending (LAD) coronary artery disease involve the apical segments of heart. However, the prognostic and therapeutic implications of the two conditions are very different. Coronary angiography is commonly performed to differentiate the two conditions. Availability of simple clinical markers may avoid the need for such invasive procedures. Therefore, the objective of the study was to determine non-invasive clinical and laboratory markers that would help differentiate the two conditions.
Methods: Between 2005 and 2010, consecutive patients who underwent coronary angiogram and had focal wall motion abnormalities on echocardiography were identified retrospectively. Patients with acute coronary syndrome who had obstructive LAD disease (n= 192) were compared with patients who had normal coronaries and an echocardiogram demonstrating wall motion abnormalities characteristic of Takotsubo cardiomyopathy (n = 30). Clinical, ECG, and laboratory variables were compared between the two groups. Baseline and follow up echocardiographic data were also compared between the two groups.
Results: The two groups were comparable with respect to age, gender, and race. Pathological Q waves were present in 31% of patients with LAD disease and only 3% of TCM patients (p< 0.001). In identifying TCM, absence of Q waves had a sensitivity of 97% and a negative predictive value of 98%. While the initial left ventricular ejection fraction (LVEF) was similarly depressed in the two groups, at follow up, LVEF was significantly greater in TCM patients (TCM group, follow up LVEF = 0.54 ± 0.11 vs. LAD group, follow up LVEF = 0.45±0.13; p = 0.005). Interestingly, there was no difference in the length of hospital stay or need for admission to intensive care unit (ICU).
Conclusions: Absence of Q wave on ECG is a highly sensitive marker of Takotsubo cardiomyopathy and has a high negative predictive value. In the absence of distinguishable echocardiographic abnormalities, a simple ECG finding may help avoid routine use of invasive procedures to differentiate the two conditions.
- © 2011 by American Heart Association, Inc.