Asymmetric hypertrophic cardiomyopathy

Q: How can hypertrophic cardiomyopathy be diagnosed? show answer

A: The diagnosis can be made in adults by a maximal end-diastolic wall-thickness ≥15 mm anywhere in the left ventricle on imaging (echo or cardiac MRI) with no other cause e.g. explained by loading conditions. In the setting of a positive family history or genetic test, the left ventricular hypertrophy can be more limited (13-14mm). Similar to adults, in children the diagnosis requires an increased left ventricular wall thickness of more than two standard deviations from the predicted mean (z-score >2).

Q: What phenotype do we have here? show answer

A: This is an asymmetric hypertrophic phenotype maybe even mass-like.

Q: What is the role of cardiac magnetic resonance (CMR) in the assessment of left ventricular hypertrophy? show answer

A: Clarification of the diagnosis in the setting of inconclusive echocardiography; evaluation regarding alternative diagnoses (e.g. storage disease, infiltrative disease, athlete's heart etc.); assessment of the extent of myocardial fibrosis; clarification of findings in the setting of left ventricular outflow obstruction.

Q: What is the clinical significance of late gadolinium enhancement? show answer

A: If present and extensive (e.g. >15% of the LV mass, as proposed by some studies) it is associated with an increased risk for ventricular tachyarrhythmias and sudden cardiac death.