Reduced inotropic reserve is predictive of further degradation in left ventricular ejection fraction in patients with Duchenne muscular dystrophy


    loading  Checking for direct PDF access through Ovid

Abstract

AimsDuchenne muscular dystrophy (DMD), an inherited X-linked muscular disease, is associated with dilated cardiomyopathy that is responsible for death in 40% of patients. Our objective was to determine whether inotropic reserve is predictive of LV trend over time.Methods and resultsA total of 69 DMD patients (age 12.2 ± 2.3 years) were investigated. At baseline, LVEF and the presence of inotropic reserve (defined as an increase in LVEF >10% during dobutamine infusion) were investigated using radionuclide ventriculography. During follow-up (FU), LVEF was remeasured after a mean 29 ± 19 months delay. In the whole population, mean LVEF was 58 ± 8% at baseline and declined to 54 ± 11% during FU (P = 0.004). At baseline, 21 patients (30.4%) had LVEF <55% and 38 had no LV inotropic reserve. LVEF declined in the 38 patients (55.1%) without LV inotropic reserve (58 ± 8% to 52 ± 10%, P = 0.001), and not in the other patients (58 ± 8% to 57 ± 11%, P = 0.516) (P = 0.042 for trends in LVEF between groups after adjustment for age, FU duration, and baseline LVEF). Fewer patients with vs. without inotropropic reserve at baseline show a depressed LVEF <55% during follow-up (35.5% vs. 63.2%, respectively, P = 0.030). Similar findings were observed in the subgroups of patients with LVEF >45% or 55% at baseline.ConclusionInotropic reserve assessment allows the distinction of DMD patients who will vs. those who will not show a deterioration in LVEF, thus offering a sensitive approach for delineating the presence and progression of cardiovascular disease in these patients.

    loading  Loading Related Articles