Stress cardiomyopathy: clinical and ventriculographic characteristics in 107 North American subjects.

Background: Stress cardiomyopathy (SCM) is a newly described reversible cardiomyopathy of largely unclear etiology. We studied SCM in a large cohort to gain further insights.

Methods: We retrospectively identified 114 cases of SCM from among 12,150 consecutive North American patients diagnosed as Troponin-positive acute coronary syndrome, from January 2000 through December 2007, at two 24-h coronary angioplasty-capable centers. Left ventriculographic wall contractility was analyzed and scored in 107 patients on the right anterior oblique view.

Results: In 107 patients (66+/-14 years, 99 females), variable regional contractility or "ballooning" was observed including: postero-basal, 1%; basal+mid-ventricular, 1%; diaphragmatic, 2%; localized apical, 2%; antero-lateral, 11%; complete mid-ventricular, 29%; and classical variant, 54%. The localized and complete mid-ventricular variants (n=45, 40 females) had a younger median age at presentation (64 vs. 71 years, p=0.008) and higher median LV ejection fraction (45% vs. 35%, p=0.006) than the classical or tako-tsubo variants (n=58, 55 females) with similar baseline exposure to stressors, risk factor and in-hospital complications. Frequency of involvement and mean contractile score (dysfunction) of the antero-lateral segment was significantly (p<0.05) greater in the order, antero-lateral>diaphragmatic>apical>basal.

Conclusion: From a single large cohort of SCM, evidence on significant individual variation in clinical and morphological pattern was confirmed. Frequency and vulnerability to transient dysfunction differs within segments with antero-lateral involvement significantly greater than diaphragmatic, apical, basal-anterior and basal-posterior LV segments. Further studies in phenotype should be undertaken for proper identification, classification and pathophysiological implications.