The investigation of respiratory chain disorders in heart using endomyocardial biopsies

Conclusion

Hitherto, cardiomyopathy has never been reported as the presenting symptom of a mitochondrial disorder. Although it appears premature to conclude as to the prevalence of defects of oxidative phosphorylation in hypertrophic cardiomyopathies, this study demonstrates that such defects should be regarded as a potential cause of idiopathic hypertrophic cardiomyopathy in early infancy. While an abnormal redox status in plasma and widespread multitissue defects support the diagnosis of mitochondrial cardiomyopathy, normal results in such investigations do not preclude the possibility of heart-specific respiratory chain defect and should prompt one to carry outin vivo investigations on endomyocardial biopsies.