Left ventricular hypertrophy

What left ventricular hypertrophy is

The left ventricle is the chamber that pumps blood to the whole body, so it already has the thickest wall. Hypertrophy means this wall has become even thicker. In most cases this is a mechanism of adaptation: when the heart has to work against an obstacle, for example high blood pressure, the muscle grows just as arm muscles do when lifting weights. At first this helps the heart cope. Over time, however, the thickened wall becomes stiffer and harder to fill with blood, receives less oxygen relative to its mass and becomes more prone to arrhythmias.

For this reason LVH is an important sign that the organ has been under stress. It is usually found incidentally on an echocardiogram or an ECG during a check for high blood pressure rather than because of complaints.

LVH should be distinguished from a condition with a similar name: hypertrophic cardiomyopathy is an inherited disease of the heart muscle in which thickening occurs without an external cause. The two can look similar on ultrasound, but they are treated differently.

Causes

• Arterial hypertension, the most common cause: the heart pushes against a higher pressure and the wall thickens over the years (see hypertension).
• Aortic valve stenosis: the narrowed valve forces the ventricle to work harder (see aortic stenosis).
• Hypertrophic cardiomyopathy, an inherited disease of the heart muscle.
• Rarer infiltrative diseases, such as amyloidosis, in which an abnormal protein is deposited in the wall, or rare metabolic diseases.
• Adaptation to intense training in athletes (“athlete’s heart”): a moderate, physiological thickening that usually does not raise risk.
• Contributing factors: obesity, sleep apnea and chronic kidney disease.

Why it matters

Depending on the cause and degree, LVH raises the risk of heart failure (especially with preserved systolic function, where the heart contracts well but does not fill well), atrial fibrillation and other arrhythmias, and coronary disease. In some types, such as high-risk hypertrophic cardiomyopathy, there is also a risk of ventricular arrhythmias.

The good news is that in LVH caused by hypertension, proper treatment can reduce wall thickness over time, and this goes with a lower risk of complications. It is therefore worth finding and treating the cause rather than just accepting a number on a report.

Symptoms

Often there are no symptoms for years. When there are, they may include fatigue, shortness of breath on exertion, chest pain or tightness, palpitations, dizziness or fainting. These complaints have many other causes too, so they are not proof of hypertrophy; but when they appear in someone with LVH they deserve assessment by a cardiologist. Fainting during exertion, especially at a young age or with a family history of sudden death, calls for immediate evaluation.

How it is diagnosed

The ECG may suggest LVH, but it can also be normal when hypertrophy is present, so it cannot rule out the diagnosis on its own. Echocardiography is the main test: it measures wall thickness, ventricular mass, heart function, filling and the state of the valves (see echocardiography). In selected cases, when the cause is unclear or when hypertrophic cardiomyopathy must be told apart from another cause, the cardiologist requests cardiac magnetic resonance imaging, which gives a more detailed picture of the muscle tissue. A Holter ECG may also be needed to look for arrhythmias.

The cardiologist interprets the finding considering body size, blood pressure, valves, sporting activity and family history. Telling an athlete’s heart from hypertrophic cardiomyopathy sometimes requires specialized assessment: in athlete’s heart the thickening is moderate, symmetrical and shrinks when training stops, while filling function remains normal.

Treatment

The cause is treated:

• In hypertension, good blood pressure control reduces ventricular mass over time. Some drug groups, such as ACE inhibitors or ARBs, are particularly effective; the doctor chooses according to the case. Cutting salt and losing weight also matter, and sleep apnea, if present, is treated too.
• In aortic stenosis, the plan is determined by the severity of the valve and may include replacing it.
• In hypertrophic cardiomyopathy or infiltrative disease, treatment is specialized and includes specific medicines, assessment of arrhythmia risk and, in some cases, a procedure.

The degree of improvement differs from patient to patient, but regular medicines, weight control and tailored physical activity always matter. Sport: restrictions are not the same for everyone; do not make decisions about intense sport from one sentence on an ultrasound report, but discuss them with your cardiologist.

Family. If there is a family history of cardiomyopathy or sudden death at a young age, tell your cardiologist: close relatives may need assessment too.

This information is educational and does not replace a medical visit.