Severe Myocardial Steatosis

Abstract

Myocardial steatosis, also known as lipomatosis cordis, is characterized by adipose tissue within the myocardium without significant fibrosis. Evidence suggests that accumulation of fat can disturb the normal electromechanical physiology of the myocardium. Herein, we discuss the case of a 60-year-old woman with a history of chronic obstructive pulmonary disease who died because of anoxic encephalopathy after a sudden cardiac arrest (SCA). An electrocardiogram showed QRS fragmentation noted as notched R in inferior leads. The autopsy revealed a very small thromboembolus in a distal subsegmental branch of the pulmonary artery, which could not explain the SCA. There was an extensive intramyocardial accumulation of adipose tissue involving the right ventricle and interventricular septum, which split the myocardium into discrete bundles. Arrhythmogenic right ventricular cardiomyopathy was ruled out based on the absence of typical fibrofatty changes. The mechanism of fat replacement was likely secondary to redistribution of visceral fat in the setting of Cushing syndrome. We propose that severe myocardial steatosis can create an anatomic substrate to facilitate the development of SCA. Myocardial steatosis should be reported to identify patients who are at risk for developing cardiovascular events secondary to extreme cardiac adiposity.

Myocardial steatosis: An autopsy-discovered case

“…Rarely, it is found in heart tissue, where it may be found in the epicardium, the endocardium, or the myocardium. Myocardial localization is the most severe type causing heart failure with a risk of sudden death [1]. The causes are usually hypoxic or metabolic.…”

Noninvasive Assessment of Lipomatous Metaplasia as a Substrate for Ventricular Tachycardia in Chronic Infarct

“…Importantly, LM is to be distinguished from the intracellular accumulation of fat droplets within cardiomyocytes. 7 Myocardial steatosis refers to fat deposition within both extracellular and intracellular space of the myocardium but without significant fibrosis 8 or mainly intracellular fat droplet accumulation without fibrosis, 9 typically concomitant with a substantial increase of epicardial adipose tissue (EAT).…”

The Silent Player

“…On the other hand, myocardial steatosis refers to the deposition of adipose tissue within both the extracellular and intracellular space of the myocardium without significant fibrosis. 18 LM is now recognized as an essential contributor to VT circuitry in patients with prior MI. 19 Xu et al 20 explained that critical VT circuit pathways pass through or near infarcted tissue adjacent to LM.…”