[Cardiac manifestations of patients with mitochondrial disease]

To analyze the cardiac manifestations of mitochondriopathy patients.

We retrospectively analyzed the clinical (Electrocardiogram, Holter monitoring, echocardiogram and laboratory examinations) and pathological data of 90 mitochondriopathy patients diagnosed within recent 20 years. The cardiac involvement data from these patients were summarized.

Hypertrophic cardiomyopathy was found in 2 patients and dilated cardiomyopathy in 3 patients Mitochondriopathy diagnosis was made in 1 patient two years after heart transplantation due to heart failure resulting from previously diagnosed hypertrophic cardiomyopathy with noncompaction. The prevalence of cardiomyopathy is 5.6% (5/90). The prevalence of various arrhythmias was 22.2% (20/90). Four patients received permanent pacemaker because of Adams-Stokes attack or bradyarrhythmias (mitochondriopathy diagnosis was made 1-3 years post pacemaker implantation in 3 cases). History of syncope, respiratory failure, RBBB, atrial fibrillation and episodic ventricular tachyarrhythmias were presented in 1 patient with mitochondriopathy, another mitochondriopathy patient developed atrial tachyarrhythmias. Arrhythmia were present in 14 mitochondriopathy patients including RBBB, bifascicular block, intraventricular block, Wolff-Parkinson-White syndrome and short PR interval syndrome. The mtDNA 3243A-G mutation was detected in 8 patients.

Incidence of cardiomyopathy, heart failure and severe arrhythmias is high in patients with mitochondriopathy. Therefore, young cardiomyopathy patients with severe conduction block disorders should undergo relevant etiologic and genetic screening for mitochondriopathy and patients with diagnosed mitochondriopathy should regularly receive electrocardiogram and echocardiography examinations for possible cardiac involvement.