Prevalence of stress-induced myocardial stunning (Tako-Tsubo cardiomyopathy) among patients undergoing emergency coronary angiography for suspected acute myocardial infarction.

Stress-induced myocardial stunning is defined as a syndrome of acute chest pain, ST-T changes on the ECG and transient left ventricular apical wall motion abnormalities mimicking acute myocardial infarction but with surprisingly normal coronary angiography findings. The aim of this retrospective study is to assess the prevalence of stress-induced myocardial stunning among patients undergoing urgent coronary angiography for suspected acute myocardial infarction. During a four-year period (2002-2005), a total of 5876 patients underwent urgent coronary angiography for suspected acute myocardial infarction at three tertiary centers. Four patients fulfilled the diagnostic criteria for stress-induced myocardial stunning. Thus, the cath-lab prevalence of stress-induced myocardial stunning (i.e. among patients undergoing urgent coronary angiography for suspected acute myocardial infarction) was estimated as 1 per 1469 ST-elevation coronary angiograms (i.e. 0.07%) The estimated annual population incidence of this rare disorder was calculated as 0.00006%. Stress-induced myocardial stunning is an extremely rare syndrome among patients undergoing emergency coronary angiography for suspected acute myocardial infarction.