Thoroughly reviewing the patient’s medical history and giving the patient a physical examination are the first steps toward a diagnosis of MVP. During this exam, the physician will listen to the patient’s heartbeat through a stethoscope (a process called auscultation). MVP can be detected by a distinctive clicking sound (and, frequently, a heart murmur) at a given point in the cardiac cycle, just after the ventricles contract.

The next diagnostic step is usually an electrocardiogram (EKG), which is a recording of the heart’s electrical activity as a graph on a moving strip of paper or video monitor. The highly sensitive electrocardiograph machine helps to detect heart irregularities, disease, and damage by measuring the heart’s rhythms and electrical impulses. However, although an electrocardiogram will provide important information, a diagnosis of mitral valve prolapse cannot be made by this test alone.

When a history, physical examination and EKG suggest the possibility of MVP, an echocardiogram will usually follow. This test can provide detailed information about the extent of valve abnormality and verify the diagnosis. An echocardiogram is an ultrasound test that uses sound waves to track the structure and function of the heart. A moving image of the patient’s beating heart is played on a video screen, where a physician can study the heart’s thickness, size and function. The image also shows the motion pattern and structure of all four heart valves, revealing any potential billowing, leakage (regurgitation) or narrowing (stenosis). During this test, a Doppler ultrasound and color Doppler are required to fully assess each valve. If MVP is diagnosed, patients are encouraged to have repeat echocardiograms performed every 2 to 5 years, depending upon the severity of the regurgitation.

The physician may need additional tests to determine how the heart responds under physical stress. Therefore, an exercise stress test may be ordered. In an effort to detect abnormal heart rhythms (arrhythmias), the exercise stress test may reveal an excessively rapid heart rhythm called a supraventricular tachycardia. It may also reveal other electrical disturbances that account for the palpitations often felt by patients with MVP.

In order to help correlate the rhythm abnormalities with the symptoms (e.g., palpitations), the physician may order a Holter monitor test. A Holter monitor is a continuous EKG that is temporarily attached to an ambulatory (freely moving) patient for a 24-hour period. This test can detect or diagnose abnormal arrhythmias. It can also help to evaluate the effectiveness of any medications, especially antiarrhythmics, that the patient may be taking.

The physician may also order a chest x-ray to see whether the heart is enlarged, or whether there is excessive fluid in the lungs.

Occasionally, a more invasive procedure called a cardiac catheterization needs to be done. As part of the cardiac catheterization, two tests may be performed: a coronary angiogram to ensure that the coronary anatomy is normal and not the cause of the chest pain, and a left ventriculogram to visualize the left ventricle and mitral valve. 

To perform the coronary angiogram, the physician inserts a thin tube (catheter) through a blood vessel, usually in the upper thigh, and up into the coronary arteries. Once the catheter is in place, the physician can inject a special dye (contrast medium) through the catheter and into the coronary arteries. Once the dye has highlighted the area, an x-ray is taken.

To perform a left ventriculogram, the catheter is then placed in the left ventricle and dye is injected. Following the injection of the dye, the physician is able to assess for the presence of MVP and the strength and motion of the left ventricle.

Although the physician typically numbs the area where he or she inserts the catheter, the patient is awake for the entire cardiac catheterization. The patient receives a mild sedative before the procedure and does not ordinarily feel the movement of the catheter within the blood vessels, although he or she may feel the contrast dye when it is injected.