A Prospective Evaluation of Clinical Characteristics of Methamphetamine-associated Cardiomyopathy (MACM) in Comparison to a Matched-cohort with Non-methamphetamine Non-ischemic Cardiomyopathy

Background With globally increasing rates of methamphetamine (MA) abuse, there is a rising prevalence of methamphetamine-associated cardiomyopathy (MACM). The condition, however, is poorly characterized, leaving clinicians with little data to guide diagnosis and management. Purpose To compare clinical characteristics of prospectively encountered patients with MACM to those with non-MA non-ischemic cardiomyopathy (NMACM). Methods Consecutive patients with MACM confirmed by history presenting to Los Angeles County (LAC)+USC Medical Center between Jun 2018 and March 2020 were interviewed and studied. We retrospectively identified an age- and gender-matched cohort of NMACM and compared demographic, laboratory, and echocardiographic data between the two groups. Results 140 patients (70 MACM and 70 NMACM) were included. Mean age was similar (49.6±10 vs 48.2±10.5 years, p=0.45) and 94% of patients were male. Patients were predominantly Hispanic in both groups (51% vs 61%, p=0.232) with a greater proportion of Caucasians in the MACM group (21% vs 6%, p=0.007). Significantly more patients with MACM were homeless (47% vs 7%, p=0.001). 20% of MACM patients were college educated. The mean and median duration of MA use prior to a diagnosis of heart failure was 9.8 and 5.5 years, respectively. Two-thirds of MACM patients reported current MA use. MACM compared to NMACM was characterized by lower left ventricular ejection fraction (LVEF) [20% vs 26%, p Conclusion Compared to an age and gender matched cohort of NMACM, prospectively identified patients with MACM had a high incidence of homelessness and significantly more severe myocardial insult with greater degree of LV and RV dilatation and depression of LV function. Frequency or amount of MA use did not appear to be associated with severity of MACM.