Endomyocardial biopsy in dilated cardiomyopathy and myocarditis: which role?

Role of myocarditis in athletes with minor arrhythmias and/or echocardiographic abnormalities

We report the clinical and instrumental data, including the endomyocardial biopsy findings, of six young athletes presenting with minor arrhythmias and/or echocardiographic abnormalities. In one of them, a left ventricular dilation with moderate depression of the systolic function had been attributed to an athlete's heart. A diagnosis of arrhythmogenic right ventricular dysplasia had been made in three others, one with right ventricular dilation and apical hypokinesia, and two with ventricular arrhythmias with QRS morphology of left bundle branch block. A myocarditis could be unequivocally established in four athletes (two with and two without fibrosis). In the remaining two, with a clinical history strongly suggesting a previously acute myocarditis, the endomyocardial biopsy specimen revealed a nonspecific fibrosis compatible but not definitely pathognomonic of a healed myocarditis. Our report suggests that a myocarditis may be a cause of minor rhythm disturbances and/or echocardiographic abnormalities in athletes. A prevalent localization of the inflammatory process in the right ventricle with or without the occurrence of ventricular arrhythmias with left bundle branch block morphology can mimic an arrhythmogenic right ventricular dysplasia. An early diagnosis of myocarditis in athletes is useful to avoid the risk of fatal arrhythmias, also considering that rest still keeps on being one of the most effective strategies in myocarditis management.

Endomyocardial biopsy in infants and children with cardiomyopathy

We reviewed our experience of endomyocardial biopsy performed on 21 symptomatic infants and children with cardiomyopathy. Clinical congestive cardiomyopathy was noted in 18 patients, 2 had hypertrophic cardiomyopathy, and 1 a restrictive cardiomyopathy. The biopsy findings led to a diagnosis of hemochromatosis in one patient, Adriamycin cardiomyopathy in another, and lymphocytic myocarditis in a third. Five patients had features of endocardial fibroelastosis, one endomyocardial fibrosis, and a further one, a mitochrondrial abnormality. In 11 patients normal or nonspecific features were seen. There were 2 myocardial perforations, both patients being successfully resuscitated. Endomyocardial biopsy, although occasionally hazardous, may sometimes provide valuable information which may lead to a diagnosis, facilitate treatment, and be of prognostic value. Despite the low positive yield, it may still be indicated in selected patients, in view of the seriousness and often poor prognosis of this disorder: 5 of our study group subsequently died.