ABSTRACT
BACKGROUND: Mitoxantrone is an effective disease-modifying therapy in multiple sclerosis (MS), but its use is limited by cardiotoxicity. We evaluated global myocardial function, including myocardial performance index (MPI), on echocardiography in MS patients after remote mitoxantrone treatment. METHODS AND RESULTS: Consecutive patients (n = 50) treated with standard-protocol mitoxantrone from 2002 to 2010 in our center were identified. After exclusion of those who had died (n = 4; all noncardiac) or had developed interim cardiovascular disease or risk factors (n = 3), 33 (mean age 49 ± 11 years, 45% male, median follow-up 77 months, mean cumulative dose 72 mg/m(2)) of the remaining patients (77%) underwent 2-dimensional echocardiography. A comparison group of 17 age- and sex-matched control subjects were included. No significant differences occurred in standard echocardiographic parameters between groups. However, mean MPI (defined as isovolumic contraction time plus isovolumic relaxation time (IVRT) divided by ejection time) was significantly higher in patients (0.51 ± 0.12 vs 0.39 ± 0.06; P = .02) owing to a significantly prolonged IVRT (81 ± 25 vs 60 ± 9 ms; P = .04). Overall MPI was >0.5 in 18 patients compared with none of the control subjects (54.5% vs 0%; P < .001). CONCLUSIONS: A subclinical form of global myocardial dysfunction reflecting primarily diastolic dysfunction may be present in MS patients after remote standard-dose mitoxantrone treatment.
Subject(s)
Cardiomyopathies/chemically induced , Cardiomyopathies/diagnostic imaging , Mitoxantrone/adverse effects , Multiple Sclerosis/diagnostic imaging , Multiple Sclerosis/drug therapy , Myocardial Contraction/drug effects , Adult , Diastole/drug effects , Diastole/physiology , Echocardiography, Doppler/methods , Female , Follow-Up Studies , Humans , Male , Middle Aged , Multiple Sclerosis/physiopathology , Myocardial Contraction/physiology , Retrospective Studies , Treatment OutcomeABSTRACT
BACKGROUND: Mitoxantrone has been extensively used as a disease-modifying therapy for multiple sclerosis. However, estimates of the associated risk of therapy-related acute leukaemia and cardiomyopathy have been derived from short-term studies. This study aimed to ascertain the long-term risk of therapy-related acute leukaemia or cardiomyopathy after mitoxantrone therapy for multiple sclerosis. METHODS: Between 2002 and 2010, 50 patients were treated with mitoxantrone at a single centre using a standard protocol (12 mg/m(2) body surface area monthly for 6 months as tolerated to a maximum of 72 mg/m(2) body surface area). Follow-up haematologic and echocardiographic data were collected in March 2011. RESULTS: Fifteen patients (30%) were excluded from analysis either because of lack of follow-up data, death due to non-cardiac and non-haematologic causes, or comorbid cardiovascular disease. The remaining 35 patients (70%) were followed for a median of 75 months (range: 9-103). The median cumulative mitoxantrone dose given was 72 mg/m(2) body surface area (range: 24-123). At the end of follow-up, no patients had developed therapy-related acute leukaemia. One patient suffered an asymptomatic drop in left ventricular ejection fraction from 55 to 47%. CONCLUSION: This series of patients followed for up to 8.5 years suggests that the risk of either therapy-related acute leukaemia or cardiomyopathy after mitoxantrone therapy for multiple sclerosis is low when patients are treated within standard protocol.
