Effects of α-lipoic acid therapy on sympathetic heart innervation in patients with previous experience of transient takotsubo cardiomyopathy

Abstract

Background: Takotsubo syndrome is a stress cardiomyopathy, characterized by reversible left ventricle (LV) apical ballooning in the absence of significant angiographic coronary artery stenosis. The frequent association with emotional stress suggests in this disease an autonomic nervous system involvement. We could think that a therapeutic treatment targeting heart sympathetic dysfunction could be of crucial importance.

Methods: From January 2010 to June 2012, 886 patients were consecutively evaluated at Cardarelli Hospital, Naples, Italy. Among these, 48 patients met takotsubo cardiomyopathy (TCM) criteria. Each patient was assessed with history and physical examination, 12-lead electrocardiogram, serum troponin, coronary arteriography, and left ventricular angiogram, perfusion myocardial scintigraphy with technetium 99m, with echocardiography and 123I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy. At discharge, the surviving patients were randomly assigned to α-lipoic acid (ALA) treatment (600mg once daily) or placebo. Following discharge, after the initial TCM event, patients returned to our outpatient clinic at Internal Medicine of the Second University Naples for the follow-up evaluation quarterly until 12 months. Routine analysis, myocardial damage serum markers, oxidative stress serum markers, pro-inflammatory cytokines, and sympathetic tone activity were evaluated in all patients.

Results: ALA administration improved MIBG defect size at 12 months compared to placebo.

Conclusions: Adrenergic cardiac innervation dysfunction in TCM patients persists after previous experience of transient stress-induced cardiac dysfunction. ALA treatment improves the adrenergic cardiac innervation. This study evaluates whether sympatho-vagal alterations are TCM event-related.

Keywords: Nitric oxide; Sympathetic heart innervation; Takotsubo cardiomyopathy; α-Lipoic acid.