Methamphetamine use is associated with systolic dysfunction, pulmonary arterial hypertension and may also be associated with diastolic dysfunction. The impact of methamphetamine cessation on methamphetamine-associated heart failure (MethHF) remains poorly characterised. We aimed to longitudinally characterise methamphetamine-associated heart failure patients with reduced (METHrEF) and preserved (METHpEF) left ventricular ejection fraction (EF), and evaluate the relationship between methamphetamine cessation and clinical outcomes.We performed a retrospective cohort study, and reviewed medical records of patients with METHrEF, METHpEF and heart failure controls without methamphetamine use. Echocardiographic variables were recorded for up to 12 months, with clinical follow-up extending to 24 months.Among METHrEF patients (n=28, mean age 51±9 years, 82.1% male), cessation was associated with improvement in EF (+10.6±13.1%, p=0.009) and fewer heart failure admissions per year compared with continued use (median 0.0, IQR 0.0-1.0 vs median 2.0, IQR 1.0-3.0, p=0.039). METHpEF patients (n=28, mean age 50±8 years, 60.7% male) had higher baseline right ventricular systolic pressure (median 53.44, IQR 43.70-84.00 vs median 36.64, IQR 29.44-45.95, p=0.011), and lower lateral E/E' ratio (8.1±3.6 vs 11.2±4., p<0.01) compared with controls (n=32). Significant improvements in echocardiographic parameters and clinical outcomes were not observed following cessation in this group.METHrEF patients who cease methamphetamine use have significant improvement in left ventricular systolic function and fewer heart failure admissions, suggesting that METHrEF may be reversible. Echocardiographic parameters suggest that some patients with METHpEF may have pulmonary hypertension in the absence of overt signs of left ventricular diastolic dysfunction, but additional study is needed to characterise this patient cohort.