Valvular Heart Disease

Valvular heart disease encompasses any cardiovascular pathology affecting one or more of the heart's four valves: the aortic and mitral valves on the left side, and the pulmonic and tricuspid valves on the right.

This condition is often age-related but can also stem from congenital abnormalities, specific diseases, or physiological processes, including rheumatic heart disease and pregnancy.

Classification

Valvular heart diseases are primarily categorised into stenosis and insufficiency/regurgitation. Stenosis refers to the narrowing of the valve orifice, impeding adequate blood outflow. Insufficiency or regurgitation denotes the valve's inability to prevent backflow, resulting from improper leaflet closure.

Signs and Symptoms

Aortic Stenosis

Aortic stenosis manifests with symptoms of heart failure such as dyspnea on exertion, orthopnea, paroxysmal nocturnal dyspnea, angina pectoris, and exertional syncope. Medical signs include diminished and delayed carotid pulse, fourth heart sound, decreased A2 sound, sustained apex beat, and a systolic murmur heard in the 2nd right intercostal space radiating to the carotid arteries.

Aortic Regurgitation

Patients may experience dyspnea on exertion, orthopnea, paroxysmal nocturnal dyspnea, palpitations, and angina pectoris. Signs include increased pulse pressure, diastolic decrescendo murmur, water hammer pulse, Austin Flint murmur, and a third heart sound.

Mitral Stenosis

Mitral stenosis presents with dyspnea on exertion, orthopnea, paroxysmal nocturnal dyspnea, palpitations, chest pain, hemoptysis, thromboembolism, or signs of right-sided heart failure. Auscultation reveals a loud S1, an opening snap, and a low-pitched diastolic rumble.

Mitral Regurgitation

Symptoms include dyspnea on exertion, orthopnea, paroxysmal nocturnal dyspnea, palpitations, or pulmonary oedema. Auscultation may reveal a holosystolic murmur at the apex, a third heart sound, and atrial fibrillation.

Tricuspid Regurgitation

Patients may experience ascites, hepatomegaly, oedema, and jugular venous distension. Signs include a pulsatile liver, prominent V waves, rapid y descents in jugular venous pressure, and a holosystolic murmur.

Diagnosis

Aortic Stenosis

Diagnosis involves chest X-ray showing aortic dilation and echocardiography revealing left ventricular hypertrophy, leaflet calcification, and abnormal leaflet closure.

Aortic Regurgitation

Chest X-ray may show aortic root dilation and apex displacement. Echocardiography is very important for identifying aortic root dilation, and regurgitant fraction (RF) is used to classify severity.

Mitral Stenosis

Chest X-ray can reveal an enlarged left atrium and pulmonary vein dilation. Echocardiography estimates pulmonary artery systolic pressure and visualises leaflet calcification and the pressure gradient.

Mitral Regurgitation

Chest X-ray may show an enlarged left atrium and pulmonary venous congestion. Echocardiography visualises regurgitant flow and calculates RF.

Treatment

Aortic Stenosis

Treatment involves aortic valve replacement (AVR) surgery for severe and symptomatic cases. AVR can be performed using mechanical or tissue valves, or via Trans-catheter Aortic Valve Implantation (TAVI) in high-risk patients. Monitoring with echocardiography is essential in non-severe cases.

Aortic Regurgitation

Treatment includes aortic valve replacement for symptomatic severe cases and chronic severe cases with left ventricular ejection fraction less than 50%. Hypertension is managed with calcium channel blockers, ACE inhibitors, or ARBs.

Mitral Stenosis

Percutaneous balloon mitral valvuloplasty (PBMV) is recommended for symptomatic severe cases. Anticoagulation is indicated in the presence of atrial fibrillation or a previous embolic event. Diuretics may be used for pulmonary congestion.

Mitral Regurgitation

Surgical repair is preferred over replacement for severe cases. Medical management includes vasodilators, diuretics, digoxin, antiarrhythmics, and chronic anticoagulation.

Epidemiology

In the United States, about 2.5% of the population has moderate to severe valvular heart disease, with prevalence increasing with age. Rheumatic heart disease is the most common cause in underdeveloped regions, accounting for up to 65% of valve disorders.

Aortic Stenosis

This condition is primarily age-related, affecting 12.4% of those over 75. Bicuspid aortic valves are found in up to 1% of the population.

Aortic Regurgitation

Its prevalence increases with age, affecting 13% of those aged 55 to 86. It is often caused by aortic root dilation or infective endocarditis.

Mitral Stenosis

Almost exclusively caused by rheumatic heart disease, its prevalence is about 0.1% in the United States and is the most common valvular heart disease in pregnancy.

Mitral Regurgitation

This condition is significantly associated with ageing, affecting over 9% of those over 75.

Special Populations

Pregnancy

Valvular heart disease in pregnancy poses risks to both the mother and foetus due to physiological changes such as increased cardiac output and decreased systemic vascular resistance. Severe conditions like aortic stenosis, mitral stenosis, and mechanical prosthetic valves requiring anticoagulation are particularly high-risk during pregnancy.

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Self-assessment MCQs (single best answer)

Which of the following heart valves is located on the right side of the heart?

Which of the following symptoms is NOT commonly associated with aortic stenosis?

Which diagnostic tool is very important for identifying the extent of left ventricular hypertrophy in aortic stenosis?

What is the primary cause of mitral stenosis in the United States?

Which treatment is recommended for severe symptomatic mitral stenosis?

Which of the following is a common sign of tricuspid regurgitation?

Which valve disorder involves the inability of the valve to prevent backflow of blood?

Which valvular disease is most commonly associated with ageing and affects over 9% of those over 75?

What is the most common cause of aortic regurgitation?

Which of the following treatments is preferred for chronic severe mitral regurgitation?