Ventricular Myocardial Fat: An Unexpected Biomarker for Long-term Survival?

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

Myocardial lipomatous metaplasia (LM) has been increasingly reported in patients with prior myocardial infarction. Cardiac magnetic resonance and cardiac contrast-enhanced computed tomography have been used to noninvasively detect and quantify myocardial LM in postinfarct patients, and may provide useful information for understanding cardiac mechanics, arrhythmia susceptibility, and prognosis. This review aims to summarize the advantages and disadvantages, clinical applications, and imaging features of different cardiac magnetic resonance sequences and cardiac contrast-enhanced computed tomography for LM detection and quantification. We also briefly summarize LM prevalence in different cohorts of postinfarct patients and review the clinical utility of cardiac imaging in exploring myocardial LM as an arrhythmogenic substrate in patients with prior myocardial infarction.

Intradermal Band-like Lipomatous Metaplasia Can Be Associated With the Regression of Overlying Skin Neoplasms: A Clinicopathologic Study of 20 Cases

ABSTRACT

Lipomatous metaplasia has been rarely reported in both neoplastic and inflammatory dermatological disorders. Most neoplastic cases show the lipomatous change within the tumor silhouette, but band-like lipomatous metaplasia in the dermis under tumors has not been well-described. The aim of this study was to reveal the characteristics and relationship of intradermal band-like lipomatous metaplasia and coexisting skin tumors. A total of 20 cases with intradermal band-like lipomatous metaplasia were retrieved from 10,992 archive cases between April 1997 and March 2020 at Hyogo Cancer Center, and subjected to a detailed clinicopathologic analysis. Nine (45%) patients had superficial variant basal cell carcinoma as a coexisting neoplasm. Eight (40%) patients had squamous cell carcinoma, 5 of which were in situ. The remaining 3 (15%) cases were invasive extramammary Paget disease. All 20 cases showed at least one of 3 signs of tumor regression, namely, partial loss of overlying neoplasia, significant inflammatory infiltrate under the tumor, and fibrosis around the tumor. We concluded that intradermal band-like lipomatous metaplasia could be seen in association with the regressing process of cutaneous superficially-spreading neoplasms.

Arrhythmogenic left ventricular cardiomyopathy

Arrhythmogenic ventricular cardiomyopathy (AVC) is a heritable heart muscle disorder characterized by fibrofatty infiltration of the myocardium. Intramyocardial fat deposition is considered arrhythmogenic and predisposes patients to life-threatening arrhythmias and sudden cardiac death. The classic subtype of AVC is characterized by fibrofatty replacement of the right ventricular myocardium (i.e. arrhythmogenic right ventricular cardiomyopathy). In advanced cases of arrhythmogenic right ventricular cardiomyopathy, the left ventricle may be involved as well. Predominantly left ventricular involvement by AVC is exceedingly rare and lack of specific diagnostic criteria as well as its potential cardiotoxic effect make its diagnosis challenging and of high importance.