Noncompacted Ventricular Myocardium: Is Syncope the Only Warning Sign?

A rare genetic variant in PRDM16 is associated with Wolff-Parkinson-White syndrome with complex accessory pathway characteristics and left ventricular non-compaction cardiomyopathy

Not only has Wolff-Parkinson-White syndrome been associated with congenital cardiac abnormalities and cardiomyopathies, but familial clustering of Wolff-Parkinson-White syndrome has also been reported. Despite these well-known associations, direct genetic aetiology is rarely implicated in patients with Wolff-Parkinson-White syndrome. We report a 17-year-old girl with Wolff-Parkinson-White syndrome and left ventricular non-compaction cardiomyopathy due to a rare genetic variant in PR-domain containing protein 16. The report is supplemented by a comprehensive review of literature on association between PRDM16, left ventricular non-compaction and Wolff-Parkinson-White syndrome.

Wolff-Parkinson-White syndrome and noncompaction in Leber's hereditary optic neuropathy due to the variant m.3460G>A

This report describes a 66-year-old Caucasian male who acutely developed severe, bilateral impairment of visual acuity at 24 years of age. Leber’s hereditary optic neuropathy (LHON) was suspected but the diagnosis was not genetically confirmed until the age of 49 years when the primary LHON mutation m.3460G>A was detected. Since onset, visual acuity had slightly improved. The family history was positive for LHON (brother, two sisters of mother, female cousin) and genetically confirmed in his brother and one aunt. Since the age of 65 years, he had experienced recurrent vertigo. His cardiological history was positive for arterial hypertension, noncompaction, myocardial thickening, intermittent right bundle-branch-block (RBBB) and Wolff-Parkinson-White (WPW) syndrome. In addition to LHON, he presented with polyneuropathy, hyperCKaemia, carotid artery occlusion, and a history of stroke. Cardiological investigations at 66 years of age revealed mildly reduced systolic function, enlarged atria, and nonsustained ventricular tachycardias. He underwent an electrophysiological investigation, but radiofrequency ablation was ruled out due to a ‘bizarre’ cardiac conduction system. Instead, an implantable cardioverter defibrillator was proposed but refused by the patient. Since the vertigo did not resolve it was attributed to polyneuropathy. This case demonstrates that LHON may be associated with noncompaction, myocardial thickening, reduced systolic function, enlarged atria, RBBB, WPW syndrome and nonsustained ventricular tachycardias. WPW syndrome in LHON may require invasive antiarrhythmic treatment.