Pediatr Cardiol 26:361–366, 2005 DOI: 10.1007/s00246-004-0742-1
The Effect of Coenzyme Q10 on Idiopathic Chronic Dilated Cardiomyopathy in Children J. Soongswang,1,5 C. Sangtawesin,2 K. Durongpisitkul,1 D. Laohaprasitiporn,1 A. Nana,1 K. Punlee,3 C. Kangkagate4 1 Division of Cardiology, Department of Pediatrics, Faculty of Medicine, Siriraj Hospital, Mahidol University, 10700 Bangkok, Thailand 2
Division of Cardiology, Department of Pediatrics, Queen Sirikit National Institute of Child health, 10400 Bangkok, Thailand 3
Her Majesty Cardiac Center, Faculty of Medicine, Siriraj Hospital, Mahidol University, 10700 Bangkok, Thailand
4
Department of Research Promotion, Faculty of Medicine, Siriraj Hospital, Mahidol University, 10700 Bangkok, Thailand 5
Department of Pediatrics, Siriraj Hospital, 2 Prannok Road, 10700 Bangkoknoi, Bangkok, Thailand
Abstract. The objective of this study was to assess the effect of coenzyme Q10 (CoQ10) as supplementation to conventional antifailure drugs on quality of life and cardiac function in children with chronic heart failure due to dilated cardiomyopathy (DCM). The study was an open-label prospective study performed in two of the largest pediatric centers in Thailand from August 2000 to June 2003. A total of 15 patients with idiopathic chronic DCM were included, with the median age of 4.4 years (range, 0.6-16.3). Presenting symptoms were congestive heart failure in 12 cases (80%), cardiogenic shock in 2 cases (13.3%), and cardiac arrhythmia in 1 case (6.7%). Sixty-one percent of patients were in the New York Heart Association functional class 2 (NYHA 2), 31% in NYHA 3, and 8% in NYHA 4. Cardiothoracic ratio from chest x-ray, left ventricular ejection fraction, and left ventricular end diastolic dimension in echocardiogram were 0.62 (range, 0.55-0.78), 30% (range, 2040), and 5.2 cm (range, 3.8-6.5), respectively. CoQ10 was given at a dosage of 3.1 ? 0.6 mg/kg/day for 9 months as a supplementation to a fixed amount of conventional antifailure drugs throughout the study. At follow-up periods of 1, 3, 6, and 9 months, NYHA functional class was significantly improved, as was CT ratio and QRS duration at 3 and 9 months follow-up with CoQ10 when compared to the baseline and post-discontinuation of CoQ10 at 9 months (range, 4.8-10.8). However, when multiple compariBiogenetech (Thailand) Co., Ltd. supported coenzyme Q10 for all patients throughout the study. Correspondence to: J. Soongswang, email:
[email protected]
sons were taken into consideration, there was no statistical significant improvement. In addition to the conventional antifailure drugs, CoQ10 may improve NYHA class and CT ratio and shorten ventricular depolarization in children with chronic idiopathic DCM. Key words: Dilated cardiomyopathy — Coenzyme Q10 — Chronic congestive heart failure Primary chronic dilated cardiomyopathy is a rare disease with high morbidity and mortality [1, 7, 13]. The clinical features and natural history are well described in adult and children [1, 6-8, 13]. Two-year survival rate has been reported to be 50-62% [8, 10, 13]. These patients have poor quality of life with frequent admission to the hospital from chronic severe congestive heart failure and arrhythmia. For decades, there has been interest improving the quality of life and outcome of these patients. Partial ventriculectomy by the Batista procedure [23] and biventricular pacing have been reported to limited improvement provide for specific groups of patients [18]. Cardiac transplantation has been performed for this group of patients since 1967 with acceptable results [4]. However, scarcity of donor organs, lifelong immunosuppression, the complication of rejection, and economic issues are limitations. Coenzyme Q10 (CoQ10) is the coenzyme of mitochondrial enzyme complexes involved in oxidative phosphorylation in the production of adenosine triphosphate (ATP) and natural antioxidants [11, 12]. Studies have demonstrated a low level of CoQ10 in blood and myocar-
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dium of patients with chronic heart failure together with improvement of myocardial function and quality of life in adults after supplementation of CoQ10 [10, 15-17, 19, 21, 22, 24]. These results drew our attention to the use of CoQ10 in pediatric patients with idiopathic chronic dilated cardiomyopathy. Patients and Methods Patients with primary chronic dilated cardiomyopathy were recruited from two of the largest pediatric centers in Bangkok-Siriraj Hospital, Mahidol University and Queen Sirikit National Institute of Child health. The study was approved by the respective institutional ethical committees. In this study, idiopathic or primary dilated cardiomyopathy is defined as follows: no associated systemic diseases that could cause myocardial dysfunction, no dysmorphic features, no persistent abnormal metabolic state, and normal major coronary arteries (by echocardiogram). Endomyocardial biopsy was done in 3 of 15 patients believed to have chronic dilated cardiomyopathy. From August 2000 to June 2003, patients who were diagnosed with primary dilated cardiomyopathy (ejection fraction
