Examples

Angiotensin-converting enzyme (ACE) inhibitors:

Angiotensin II receptor blockers (ARBs):

Nitrates:

How It Works

Vasodilators work on different substances in the body to help widen (dilate) blood vessels.

Why It Is Used

Vasodilators are used for mitral valve regurgitation (MR) because the wider blood vessel will reduce resistance in blood flow and make it easier for blood to move forward from the left atrium to the left ventricle to the aorta. This helps reduce the amount of blood that leaks backward through the valve into the left atrium.

How Well It Works

Data support the use of vasodilators for those with acute and chronic MR when the left ventricle is enlarged. But there are no data to support using vasodilators in mitral valve regurgitation with no symptoms or with normal ventricular function.¹

Side Effects

Hydralazine may lower blood pressure, which may cause symptoms of dizziness, weakness, fainting, or fluid retention. People whose blood pressure is low when they start therapy will generally be started with a low dose and may need close monitoring to avoid reducing blood pressure too much. Hydralazine may also result in an allergic reaction (difficulty breathing; closing of the throat; swelling of the lips, tongue, or face; or hives); numbness, tingling, pain, or weakness of arms or legs; irregular or very fast heartbeat; new or chest pain or chest pain getting worse; or fainting.

ACE inhibitor side effects may include:

• Dry cough.
• Rash or itching.
• Symptoms that are like allergy symptoms.
• Allergic reaction with generalized swelling (angioedema) or, in rare cases, swelling of the upper airway.
• Excess potassium in the body (hyperkalemia), especially in people with kidney failure.

ACE inhibitors may interact with anti-inflammatory medicines, antacids, potassium supplements, certain diuretics, and lithium.

ARB side effects may include:

• Diarrhea.
• Stomach problems.
• Muscle cramps.
• Back and leg pain.
• Dizziness.
• Insomnia.
• Nasal congestion.
• Sinus problems.
• Upper respiratory infection.

Nitrate side effects may include:

• Feeling of pulsating fullness in the head (most common side effect), which can also cause headache.
• Drop in blood pressure, which can cause dizziness.
• Burning sensation under the tongue (with sublingual nitroglycerin).

Nitroprusside is generally only used for acute mitral regurgitation in the hospital. If nitroprusside is used, you are closely watched, because this medicine may cause severe low blood pressure.

See Drug Reference for a full list of side effects. (Drug Reference is not available in all systems.)

What To Think About

ACE inhibitors must be used carefully in people with severe kidney failure caused by diabetic nephropathy. A low dose is tried first. Potassium levels and kidney function are watched closely as the dose is increased.

Although vasodilators are used in acute MR, the benefits of using them for chronic MR are less clear.

If you are pregnant or may become pregnant, do not take ACE inhibitors or ARBs. If you are pregnant or breast-feeding or if you may become pregnant, talk to your doctor before you take other vasodilator medicines. These medicines may be harmful to a fetus or to a baby who is breast-feeding.

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References

Citations

1. Bonow RO, et al. (2006) ACC/AHA 2006 guidelines for the management of patients with valvular heart disease. A report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 1998 Guidelines for the Management of Patients with Valvular Heart Disease). Circulation, 114(5): e84–e231.