While LVH itself is not a disease, it is usually a marker for disease involving the heart. Disease processes that can cause LVH include any disease that increases the afterload that the heart has to contract against, and some primary diseases of the muscle of the heart.
The principal method to diagnose LVH is echocardiography, with which the thickness of the muscle of the heart can be measured. The electrocardiogram (ECG) often shows signs of increased voltage from the heart in individuals with LVH, so this is often used as a screening test to determine who should undergo further testing.
Two dimensional echocardiography can produce images of the left ventricle. The thickness of the left ventricle as visualized on echocardiography correlates with its actual mass. Normal thickness of the left ventricular myocardium is from 0.6 to 1.1 cm (as measured at the very end of diastole. If the myocardium is more than 1.1 cm thick, the diagnosis of LVH can be made.
Left ventricular hypertrophy with secondary repolarization abnormalities as seen on ECG
There are several sets of criteria used to diagnose LVH via electrocardiography. None of them are perfect, though by using multiple criteria sets, the sensitivity and specificity are increased.
The enlargement is not permanent in all cases, and in some cases the growth can regress with the reduction of blood pressure.
LVH may be a factor in determining treatment or diagnosis for other conditions. For example, LVH causes a patient to have an irregular ECG. Patients with LVH may have to participate in more complicated and precise diagnostic procedures, such as imaging, in situations in which a physician could otherwise give advice based on an ECG.
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