From the Guidelines
Moderate right ventricular dysfunction is most commonly caused by conditions that increase pressure in the pulmonary circulation, such as pulmonary hypertension, left heart failure, and pulmonary embolism, as well as direct effects on the right ventricle like right ventricular infarction, according to the American Heart Association's scientific statement on the evaluation and management of right-sided heart failure 1.
Causes of Right Ventricular Dysfunction
The causes of moderate right ventricular dysfunction can be diverse, including:
- Primary cardiomyopathies with right ventricular involvement
- RV ischemia and infarction
- Volume loading caused by cardiac lesions associated with congenital heart disease and valvular pathologies
- Pressure loading resulting from pulmonic stenosis or pulmonary hypertension from a variety of causes, including left-sided heart disease, as outlined in the scientific statement from the American Heart Association 1.
Management of Right Ventricular Dysfunction
Management of right ventricular dysfunction typically involves treating the underlying cause while providing supportive care. For pulmonary hypertension, medications such as phosphodiesterase-5 inhibitors (e.g., sildenafil), endothelin receptor antagonists (e.g., bosentan), or prostacyclin analogs may be prescribed, as discussed in the context of right-sided heart failure management 1.
Key Considerations
It's crucial to understand that the right ventricle has a thinner wall than the left ventricle, making it more susceptible to pressure overload but more adaptable to volume overload, which explains why different conditions affect right ventricular function in varying ways, as noted in the assessment of right ventricular function in the research setting 1.
Research and Clinical Implications
Further research is needed to address knowledge gaps in clinical and basic right ventricular research, including enhancing mechanistic understandings of adaptive versus maladaptive right ventricular responses to pulmonary vascular load, deriving and validating biomarkers for accurate evaluation of right ventricular function, and developing novel therapies aimed at targeting right ventricular myocardial contractility, as highlighted in the American Thoracic Society research statement 1.
From the Research
Causes of Moderate Right Ventricle Dysfunction
- Pulmonary embolism: a condition where thrombi from deep vein thrombosis dislodge and obstruct pulmonary arteries, raising pulmonary artery pressure and straining the right ventricle 2
- Chronic pulmonary hypertension: a condition where the right ventricle is subjected to increased afterload, leading to hypertrophy and potential dysfunction 3, 4
- Increased afterload: the right ventricle is not well suited to deal with pressure overload, and increased afterload can lead to right ventricular dysfunction 3, 5
- Volume overload: the right ventricle can also be affected by volume overload, which can lead to dysfunction 5
- RV cardiomyopathy: a condition where the right ventricle is affected by intrinsic contractile dysfunction, which can lead to right ventricular dysfunction 5
Pathophysiology of Right Ventricle Dysfunction
- The right ventricle plays a pivotal role in patients with pulmonary hypertension, and its adaptation to pressure overload determines a patient's functional status as well as survival 3
- The balance between the degree of RV contractility and afterload determines stroke volume, and hypertrophy is one of the major hallmarks of RV adaptation 3
- However, hypertrophy can also cause stiffening of the ventricle, making ventricular filling more difficult, and the right atrium tries to compensate through increased stroke work 3
- The interaction of RV diastolic stiffness and right atrial function determines RV filling, but also causes vena cava backflow 3
Clinical Implications of Right Ventricle Dysfunction
- Right ventricular dysfunction can lead to reduced cardiac output, impaired contractility, and potential development of chronic thromboembolic pulmonary hypertension 2
- Clinically, pulmonary embolism may present with symptoms such as dyspnea, pleuritic chest pain, and tachycardia, and diagnosis is typically confirmed through computed tomography pulmonary angiography, biomarkers, and clinical scoring systems 2
- Effective early diagnosis and management are crucial, as severe pulmonary embolism can significantly increase mortality and lead to serious complications 2