Obesity cardiomyopathy and systolic function: obesity is not independently associated with dilated cardiomyopathy.

Obesity is a growing worldwide problem and the prevalence of heart failure is also on the rise. Obesity itself is an independent risk factor for the development of heart failure and the case of obesity-related heart failure is thought to be multifactorial. Obesity leads to increased central and total blood volumes along with decreased systemic arterial resistance resulting in high cardiac output state related adaptations in the cardiac structure. Persistence of these hemodynamic changes ultimately results in diastolic dysfunction, however, whether these changes progress to significant systolic dysfunction or not is doubtful. Some MUGA (Multi Gated Acquisition) scan-based studies had shown mild degree of left ventricular systolic dysfunction in the obese, however, these findings could not be confirmed with recent echocardiogram-based studies. Using extensive literature review, we found no evidence of obesity-related cardiomyopathy leading to significant systolic dysfunction fulfilling criterion for the diagnosis of dilated cardiomyopathy (LVEF <35 %). Therefore, any obese patient presenting with severe LV dysfunction should prompt further investigations to evaluate for the underlying etiology.