Perspective:

The following are 10 points to remember from a review article on management of left ventricular hypertrophy (LVH) of initially unknown origin:

1. Determination of the underlying etiology of LVH (frequently defined by an LV wall thickness of at least 13 mm) begins with a patient’s history with emphasis on his/her family history.

2. Transthoracic echocardiography remains the initial screening modality of choice to detect the presence of LVH.

3. As the extremes of LVH seen in athletes (with a presumably ‘physiologic’ form of LVH) overlap with those seen in patients with morphologically mild hypertrophic cardiomyopathy (HCM), cardiac magnetic resonance (CMR) imaging may be helpful to distinguish these two entities. A cut-off value of <0.15 mm x m²/ml for diastolic wall-to-volume ratio can differentiate an athlete’s heart from pathological cardiac hypertrophy.

4. The structural changes of hypertensive heart disease include not only LVH, but also decrease in intramyocardial capillary density and arteriolar wall thickening.

5. In familial HCM, patchy or confluent late-gadolinium enhancement (LGE) on cardiac MRI may be seen, predominantly at the insertion points of the right ventricle into the left ventricle. There is a potential role for LGE as an arbitrator in decision making for primary prevention with implantable cardioverter-defibrillator therapy in patients with HCM.

6. There are three frequently encountered forms of systemic amyloidosis: 1) acquired monoclonal immunoglobulin light chain amyloidosis (AL), 2) hereditary transthyretin (TTR) related form (ATTR), and 3) wild-type TTR, also called ‘senile’ systemic amyloidosis primarily affecting the hearts of older men. Cardiac disease is rapidly progressive in AL, but disease course is more benign with ATTR or senile systemic amyloidosis.

7. LGE-CMR demonstrates a distinct pattern in amyloidosis with distribution over the entire subendocardial circumference.

8. If there are extracardiac features or a pattern of maternal inheritance, consider mitochondrial myopathy.

9. Anderson-Fabry disease is a lysosomal storage disorder with systemic manifestations (renal failure, corneal deposits, and nervous, gastrointestinal, and cutaneous abnormalities). LGE is found in up to 50% of patients, often in a characteristic pattern affecting the basal and/or apical inferolateral wall.

10. Glycogen storage diseases (or mucopolysaccharidoses) are inherited and rare lysosomal storage disorders characterized by systemic manifestations, LVH, and valve thickening and dysfunction.