Serial evaluation of microcirculatory dysfunction in patients with Takotsubo cardiomyopathy by myocardial contrast echocardiography.

BACKGROUND: Stress cardiomyopathy manifests as reversible left ventricular apical ballooning in the absence of epicardial coronary obstruction. Transient microcirculatory dysfunction has been proposed as a potential putative mechanism. This study aimed to understand the natural history of this dysfunction using readily available noninvasive methods. HYPOTHESIS: Stress cardiomyopathy presents with profound microvascular dysfunction that improves quickly over a period of 3 to 4 weeks.
METHODS: Nine consecutive patients with Takotsubo cardiomyopathy were followed serially with myocardial perfusion echocardiograms at 24 hours, within 1 week, and 3 to 6 months after index admission.
RESULTS: The mean left ventricular ejection fraction (LVEF) steadily improved from 38% at baseline to 48% within 1 week to 67% by the end of 3 to 6 months follow-up. The number of wall segments with reduced or absent perfusion decreased from 4.1 at baseline to 2 at 1 week. By 3 to 6 months, perfusion had returned to normal in all but 1 segment in 1 patient. At 1 week, the relative improvement in mean LVEF was 26%, whereas perfusion had improved by nearly 50%, suggesting a fairly pronounced improvement in microcirculatory function prior to recovery of wall motion.
CONCLUSIONS: Patients with Takotsubo cardiomyopathy present with significant acute microcirculatory dysfunction that recovers quickly prior to the recovery of regional wall motion abnormalities.