Stress-induced cardiomyopathy in Sweden: evidence for different ethnic predisposition and altered cardio-circulatory status.

Background: In this paper, we report about new insights regarding clinical course, long-term outcome, ethnic/genetic predisposition and cardio-circulatory status in the large stress-induced cardiomyopathy (SIC) cohort from Sweden.

Methods And Results: We have included 115 consecutive SIC patients between January 2005 and January 2010 at Sahlgrenska University Hospital in Gothenburg. Hemodynamic status and sympathetic nerve activity were evaluated and compared with those of healthy controls. Mean age was 64, and 14% were males. Thirty-day and 3-year mortality was 6 and 10%, respectively. Eleven percent had ischemic heart disease, 3% developed thromboembolic complications, 6% had cardiac arrest and 14% developed cardiogenic shock. The great majority of SIC patients (93%) were ethnic Swedes. In three families, several close relatives developed SIC. Fourteen percent developed two or more episodes of SIC. Hemodynamic evaluation has shown subnormal systemic vascular resistance, 22% lower sympathetic activity and preserved cardiac output in SIC patients.

Conclusions: SIC affects both men and women of different ages and is associated with significant short- and long-term mortality. There is a strong signal for the presence of ethnic/genetic predisposition to develop SIC. Sympathetic activity and systemic vascular resistance are lower in SIC patients, suggesting that SIC is a cardio-circulatory phenomenon.