What is Drug-Induced Valvular Heart Disease?
Drug-induced valvular heart disease (DIVHD) is a condition where the shape and functioning of the heart valves are affected due to the use of certain medications. This disease is primarily identified through changes seen in heart scans of people at risk. It was first linked with a group of medications known as ergot alkaloids back in the mid-1960s, after patients using these drugs were found to have changes in their heart scans. It is well known that these drugs cause the growth of cells within the heart valves and this can lead to inadequate functioning of these valves. This happens because these medications stimulate something called 5-HT2B receptors within the heart.
What Causes Drug-Induced Valvular Heart Disease?
Several drugs have been linked to DIVHD, a type of heart valve disease. These drugs include anti-migraine medications such as ergotamine and methysergide, first noticed in 1967.
In 2002, some medications used for Parkinson’s disease and hyperprolactinemia, namely pergolide and cabergoline, were associated with changes in heart valves among those who used them.
Certain weight-loss drugs designed to decrease appetite in individuals with obesity such as fenfluramine, dexfenfluramine, and phentermine, have also been connected to heart valve problems in several research studies.
In 2007, the recreational drug MDMA — often known as ecstasy — was identified as a potential cause of heart valve disease. A study found that 8 out of 28 people who used an average of 3.6 tablets of MDMA each week over six years developed this condition, compared to nobody in the control group. The study showed a link between the amount of MDMA used and the seriousness of the heart valve disease.
Risk Factors and Frequency for Drug-Induced Valvular Heart Disease
The occurrence of drug-induced valvular heart disease (DIVHD) can vary significantly based on the specific medication involved.
- Certain weight loss drugs, “anorexigens,” have been associated with varying levels of heart valve disease, seen in 6% to 30% of users in different studies. One study indicated that nearly 23% of people using weight-loss drugs had heart valve problems, compared to just over 1% in a control group.
- Users of the medications pergolide and cabergoline have a higher chance of experiencing heart valve leakage, compared to other similar drugs. One 2007 research project indicated that roughly 23% of people using pergolide and up to 29% of those using cabergoline had an increased risk of this condition.
- In a different 2007 study, the group using pergolide showed an over 7-fold increase in heart valve leakage, while the group using cabergoline had a nearly 5-fold increase, compared to other dopamine drugs.
- In 1967, a study was published revealing that 36 patients treated with a medication called methysergide had either mitral or aortic valve leakage. In 1974, a drug called ergotamine was also linked to left-sided valve heart disease.
- One more study investigated users of the recreational drug MDMA, often called ecstasy. Out of 29 subjects studied, eight of them (28%) had significant heart valve leakage.
Signs and Symptoms of Drug-Induced Valvular Heart Disease
The severity of the symptoms in patients with faulty heart valves can vary. Some common symptoms include difficulty breathing during physical activity, sudden difficulty breathing at night, and difficulty breathing while lying flat. Another possible sign is a new heart murmur, which can be detected during a physical examination.
Testing for Drug-Induced Valvular Heart Disease
An echocardiogram, a type of heart imaging test, is the best method to check for drug-induced heart valve disease (DIVHD). DIVHD often doesn’t have obvious symptoms. According to guidelines from the Food and Drug Administration, significant cases of DIVHD involve a certain level of aortic or mitral regurgitation, which means the heart valves aren’t closing properly and blood is leaking back into the heart chambers.
In most cases, the backflow of blood is due to the heart valve not moving freely, especially the rear leaflet of the mitral valve. Sometimes, the front leaflet can also be affected. In aortic regurgitation, varying levels of retraction or inward pulling of the valve leaflets have been noted to cause the insufficiency. These faulty valves show signs of mild to moderate thickening without hardening or severe merging of the valve parts.
The diseases affecting the tricuspid and pulmonary valves, although less common, display similar changes in the valves when examined through an echocardiogram. Notably, DIVHD has not been linked to valvular stenosis, a condition where the valves of the heart become narrowed.
Treatment Options for Drug-Induced Valvular Heart Disease
The severity of the backflow of blood (regurgitation) decides the course of treatment. In most cases, stopping the medication that causes this condition improves the situation. But some patients may need to replace their heart valve with surgery, even if they’ve been off the medication for many years.
What else can Drug-Induced Valvular Heart Disease be?
- Sudden heart conditions (Acute coronary syndrome)
- Physical injury to the stomach area (Blunt abdominal trauma)
- Heart diseases
- Narrowing of the heart valve that connects the left heart chamber (Mitral stenosis)
- Backflow of blood due to a weak heart valve (Mitral regurgitate)
- Heart attack (Myocardial infarction)
- Backflow of blood into the lungs (Pulmonary regurgitation)
- Overactive nerve responses (Sympathetic overdrive)
- Narrowing of the heart valve that prevents blood from returning to the heart (Tricuspid stenosis)
- Loss of body fluids (Volume depletion)
