Systolic and Diastolic Mechanics in Stress Cardiomyopathy
Background—Stress cardiomyopathy (SCM) is a peculiar form of reversible LV dysfunction, seen predominantly in women, and occurs in response to emotional or physical stress. Since dysfunction in SCM is reversible, while that of acute myocardial infarction (MI) is not, we hypothesized that these fundamental mechanistic differences between SCM and MI would be associated with different systolic and diastolic properties.
Methods and Results—We examined 3 groups, all women: SCM (n=24, mean age 63±12), left anterior (LAD) ST elevation MI (n=36, mean age 63±10) and referent controls (C) (n=30, mean age 62±8). All underwent angiography, ventriculography, and pressure measurements within 48 hours of presentation. LV volumes, diastolic pressures, and diastolic stiffness were higher in SCM and LAD MI than C, but no different from each other. Similarly, LV diastolic pressures and diastolic stiffness were elevated in SCM and LAD MI, compared with control. LV ejection fraction in SCM and LAD MI were 40.8 ± 12.3, 49.6 ± 5.6 %, respectively, vs. 70.4 ± 9.4 % in C, p<0.001, and stroke work less than half the value of C. Indices of contractility and ventricular-arterial coupling were similarly abnormal in SCM and LAD MI.
Conclusions—SCM and LAD MI show severe diastolic dysfunction: at similar LV volumes, their diastolic pressures are more than twice as high as control; systolic dysfunction is equally reduced in SCM and LAD MI. Despite a completely different pathophysiology, as far as systolic and diastolic function, SCM is indistinguishable from acute LAD territory MI.
- Received March 31, 2013.
- Revision received December 13, 2013.
- Accepted January 17, 2014.