Right ventricular (RV) dysfunction is a condition where the right side of the heart struggles to pump blood effectively. This impairment means the right ventricle cannot adequately move deoxygenated blood to the lungs.
Understanding the Right Ventricle
The right ventricle is one of the heart’s four chambers, located below the right atrium. Its role is to receive deoxygenated blood returning from the body. This blood enters the right atrium, passes through the tricuspid valve, and fills the right ventricle.
From the right ventricle, this deoxygenated blood is pumped through the pulmonary valve into the pulmonary artery, which carries it to the lungs. In the lungs, the blood releases carbon dioxide and picks up oxygen before returning to the left side of the heart. The right ventricle operates within a lower-pressure system compared to the left ventricle, which pumps oxygenated blood to the entire body.
The right ventricle is thinner-walled than the left ventricle. This structural difference reflects its function against the lower resistance of the pulmonary circulation.
Causes of RV Dysfunction
RV dysfunction can arise from conditions that increase the workload on the right ventricle or directly impair its pumping ability. Lung diseases are a common cause, often leading to increased pressure in the pulmonary arteries. Conditions like chronic obstructive pulmonary disease (COPD) and pulmonary embolism (PE) can significantly strain the right ventricle.
In COPD, chronic hypoxemia and destruction of pulmonary vascular beds increase pulmonary vascular resistance, forcing the right ventricle to work harder. Similarly, a pulmonary embolism, where blood clots obstruct pulmonary arteries, acutely raises pulmonary artery pressure and afterload on the right ventricle, potentially leading to rapid dysfunction.
Left-sided heart failure is another frequent cause. When the left ventricle cannot pump blood efficiently, blood can back up into the lungs, increasing pulmonary circulation pressure. This makes it more difficult for the right ventricle to pump blood into the lungs, leading to increased workload and eventual dysfunction.
Pulmonary hypertension (PH), characterized by high blood pressure in the lung arteries, is a common underlying cause. The right ventricle initially thickens its walls (hypertrophy) to maintain blood flow. However, if pressure overload continues, the right ventricle may eventually dilate and lose its ability to pump effectively, leading to failure.
Certain congenital heart defects can also predispose individuals to RV dysfunction. These include conditions causing chronic pressure or volume overload on the right ventricle, such as tetralogy of Fallot or atrial septal defects. Over time, these structural abnormalities can lead to progressive enlargement and impaired function.
Recognizing the Signs
The inability of the right ventricle to effectively pump blood leads to a buildup of pressure in the venous system, causing noticeable signs. Shortness of breath, particularly during physical exertion, is a common symptom. This occurs because the impaired right ventricle struggles to move blood to the lungs for oxygenation, leading to reduced oxygen delivery to the body.
Swelling (peripheral edema) frequently appears in the legs, ankles, and feet. This fluid retention results from increased pressure in the veins, forcing fluid out into surrounding tissues. In more advanced cases, fluid can also accumulate in the abdomen (ascites), and the liver may become enlarged due to congestion.
Fatigue is another prevalent symptom, described as a reduced capacity for physical activity. This arises from the heart’s decreased ability to pump enough oxygenated blood to meet the body’s metabolic demands. Patients may also experience chest discomfort or lightheadedness, especially with increased activity, as the heart struggles to maintain adequate blood flow.
Diagnosis and Management Approaches
Diagnosing RV dysfunction involves clinical assessment and specialized tests to evaluate heart structure and function. An echocardiogram, an ultrasound of the heart, is a common initial diagnostic tool. It visualizes the right ventricle’s size, shape, and pumping ability, and can help estimate pulmonary artery pressure and assess interventricular septum movement, indicating right ventricular strain.
Other diagnostic tools include an electrocardiogram (ECG), which can reveal signs of right ventricular hypertrophy or strain, and blood tests for markers like B-type natriuretic peptide (BNP) or cardiac troponin, indicating heart muscle stress. Advanced imaging techniques such as CT scans and cardiac MRI provide more detailed anatomical and functional information, especially when echocardiography images are limited.
Management of RV dysfunction focuses on addressing the underlying cause to reduce strain on the right ventricle. Treating lung diseases, managing left-sided heart failure, or lowering pulmonary hypertension are common approaches. Medications are often prescribed to improve heart function, reduce fluid retention, or decrease the workload on the right ventricle.
Diuretics (“water pills”) help reduce fluid buildup and swelling. Other medications might improve the heart’s pumping strength or relax blood vessels in the lungs to reduce resistance. Lifestyle modifications, such as dietary changes to limit sodium intake and controlled physical activity, are also encouraged to support overall heart health.
In some situations, advanced therapies or surgical interventions may be considered. These include mechanical circulatory support devices, like ventricular assist devices, to help the heart pump blood, or in severe cases, a heart transplant. Management is individualized, depending on the dysfunction’s severity and the patient’s overall health.