Cardiac Recovery Possible in Patients With Cardiomyopathy Related to Methamphetamine Abuse

Giving hope to patients with methamphetamine-associated cardiomyopathy, a German study has shown that severe impairments in cardiac function may be partially reversed by stopping use of the drug, with accompanying improvements in heart failure symptoms.

Continuing abuse, on the other hand, is associated with persistently compromised cardiac function and worse clinical outcomes, lead author Stephan Schürer, MD (University of Leipzig, Germany), and colleagues report in a study published in the June 2017 issue of JACC: Heart Failure.

Moreover, they found the extent of myocardial fibrosis on biopsy—which worsens with a longer duration of methamphetamine use—correlates negatively with the likelihood of recovering cardiac function.

“These findings confirm those derived from animal studies and show for the first time that there are time-dependent changes leading at some point to irreversible fibrosis, which is associated with a worse outcome,” senior author Norman Mangner, MD (University of Leipzig), told TCTMD in an email. “Furthermore, our data support the thesis that stopping methamphetamine is mandatory to recover cardiac function and improve symptoms.”

But this study, which included 30 patients with already severely impaired cardiac function and poor symptoms, “only shows the tip of the iceberg,” he said, adding, “I suppose that there are many patients [who have] subclinical changes at early phases of their drug abuse.” In a future study, he said, the investigators will evaluate patients undergoing withdrawal therapy for methamphetamine use to look at cardiac changes in the absence of heart failure symptoms.

Commenting for TCTMD, David Shaw, MD (Scripps Health, San Diego, CA), said the study is important in that it confirms prior research.

“We and others have reported that if you continue to use or abuse methamphetamines, your heart failure gets progressively worse and you often die,” Shaw said. “If you abstain, there is a high probability of recovery, and I think that’s an extremely important point that everyone—the medical community and the greater community of people who are affected by methamphetamine—needs to be aware of. So there’s both hope and grave danger.”

Methamphetamine use has been linked to numerous cardiac complications, including malignant hypertension, arrhythmias, aortic dissection, MI secondary to vasospasm, stroke, and cardiomyopathy, according to Schürer et al. Proposed mechanisms include catecholamine excess, direct toxic effects, and others.

 

The cardiac effects of methamphetamine abuse represent a pertinent issue considering that abuse of the drug is a growing problem around the world. In fact, Shaw and his colleagues reported last year that there was a significant increase in hospitalizations for methamphetamine-associated congestive heart failure at their hospital between 2009 and 2014. Shaw said data from San Diego County reflected a similar rise in emergency room admissions over the same span.

 

“Physicians should be aware of the possibility that heart failure is due to or associated with meth and remember to ask about it and also to screen for it,” he said, noting, however, that ingestion of certain cold medications also could yield a positive urine test.

A Deeper Look

To explore histopathological changes in the myocardium associated with methamphetamine-associated cardiomyopathy and patient outcomes, which have not previously been well described, the investigators looked at 30 patients (mean age 30.3 years; 93.3% men) treated in Germany. Mean duration of methamphetamine abuse was 5.7 years, ranging from 1 to 15 years. Use of other drugs, including nicotine, alcohol, cannabis, heroin, and cocaine, was common.

All patients had an LVEF below 40% (mean 19%) at baseline, and most (83.3%) had NYHA class III or IV dyspnea. Echocardiography also revealed marked LV dilatation, in addition to intraventricular thrombi in one-third of the cohort. Cardiac catheterization excluded CAD in all but one patient.

Endomyocardial biopsies performed at the initial diagnosis in all patients uncovered markers of inflammation, myocyte damage, and fibrosis.

Over an average follow-up of 35 months, 23 patients stopped using methamphetamines and seven continued. Those who quit achieved a higher LVEF (43% vs 21%; P < 0.001) and tended to have greater improvements in symptoms. The only factor independently associated with LVEF at follow-up was the extent of fibrosis.

Death, nonfatal stroke, or rehospitalization for heart failure occurred more frequently in patients with continued methamphetamine abuse (57.1% vs 17.4%; P = 0.037).

More Donor Hearts, but at What Cost?

In an accompanying editorial, Tariq Ahmad, MD (Yale University School of Medicine, New Haven, CT), and colleagues look at the issue from a different angle: the impact of increasing drug use on the supply of donor hearts.

They point out that there was a surge in cardiac transplantations in 2016, which is good news for patients seeking new hearts but raises questions about why there are so many more donor organs available. The explanation, the editorialists say, seems to be swelling numbers of drug-related deaths.

“Workers in the field of advanced heart failure must perpetually operate with conflicting emotions: on the one hand, our patients waiting for a heart are given another chance, whereas on the other hand, this opportunity is coming at a dark cost,” they write.

 

This study, which “provides objective data in support of the presumption that cardiac function will improve only after cessation of drug abuse,” Ahmad et al continue, might have implications for using donor hearts from a population with a growing proportion of drug-related deaths.

 

“More data are needed to understand the short- and long-term implications of using donor hearts from patients with a history of methamphetamine use,” they said. “Additionally, in the future, increasing knowledge of the microscopic and biochemical effects of methamphetamine use may allow us to ‘optimize’ suboptimal donor hearts and continue to increase the donor pool from this demographic group.”