Background Some cases of advanced heart failure with dilated cardiomyopathy (DCM) are complicated by neuromuscular diseases, such as muscular dystrophy. The prognosis in DCM with muscular dystrophy is worse than that of DCM alone [1]. Lamin mutations are associated with significant arrhythmia and cardiomyopathy burden, and mutation of the lamin A/C gene is associated with variable skeletal muscle involvement [2]. Therefore, the prognosis in a patient with DCM is worse if the patient also has a lamin gene mutation.

BackgroundSarcopenia is generally complicated with patients with chronic heart failure (CHF) and its presence negatively affects the course of heart failure, however effective nutritional intervention had not been elucidated yet. The primary objective of this study is to explore whether the addition of a branched-chain amino acid (BCAA) preparation for cardiac rehabilitation (CR) of patients with CHF further improves cardiopulmonary functions, skeletal muscle functions, and metabolism in comparison with conventional CR.MethodsThis is a randomized, parallel-group comparative study. The elderly patients that were participated in CR and complicated with left ventricular systolic or diastolic dysfunction are randomized into two groups, CR + BCAA and CR. 20 weeks later, the second randomization is performed, which divide subjects into two groups with and without BCAA intervention without CR. Primary outcome measure is the rate of change of the anaerobic threshold workload from baseline to post-intervention. Secondary outcome include parameters of exercise capacity, cardiac function and psychological status.DiscussionIn the current study the effect of a promising new intervention, BCAA, will be assessed to determine whether its addition to CR improve exercise capacity in patients with heart failure, who are generally complicated with sarcopenia.Trial registrationThis clinical trial was registered with the University Hospital Medical Information Network—Clinical Trials Registry (UMIN–CTR; JPRN–UMIN R000022440).

To investigate the effect of atrial fibrillation (AF) on the oxygen uptake and exercise tolerance, we evaluated cardiopulmonary exercise test (CPET) data in AF patients and heart rate-matched controls with sinus rhythm (cSR) who received ambulatory cardiac rehabilitation. We compared CPET data between AF (N = 27) and cSR patients (N = 106) who had similar HRs at rest and the peak points. Oxygen uptake (VO2)/kg and relative O2 pulse (ml/bpm/kg) at rest and the anaerobic threshold (AT) level was not different between AF and cSR patients, but these parameters above the AT level were significantly lower in AF than in cSR patients. Concisely the parallel increase of relative O2 pulse during exercise was blunted above the respiratory compensation level (Rc) in the AF group. In addition, the HR change during exercise was inversely correlated with the increase of the O2 pulse above the AT level and this inverse correlation was more prominent in AF patients than in cSR patients. In conclusion, the value of VO2 was significantly lower above the AT level in AF patients. The trend of O2 pulse above the AT level was strongly associated with the detrimental response of HR increase and the response was markedly exaggerated in the AF patients.