From the Guidelines
Rheumatic heart disease is associated with both volume and pressure overload, depending on the specific valve lesions present, with mitral stenosis and mitral regurgitation being the most common causes of pressure and volume overload, respectively. The disease can affect various heart valves, including the mitral and aortic valves, leading to different types of overload. Mitral stenosis, for example, creates a pressure overload in the left atrium and pulmonary circulation, as blood faces resistance when flowing from the left atrium to the left ventricle 1. On the other hand, mitral regurgitation causes volume overload in the left atrium and ventricle as blood flows backward into the atrium during ventricular contraction 1.
When the aortic valve is affected, aortic stenosis results in pressure overload of the left ventricle, while aortic regurgitation leads to volume overload. The underlying mechanism involves an autoimmune response following group A streptococcal infection, where antibodies cross-react with heart tissues, causing inflammation and scarring of the heart valves 1. Over time, this scarring leads to valve deformities that create these hemodynamic abnormalities.
Key points to consider in the management of rheumatic heart disease include:
- The type and severity of valve lesions present
- The presence of symptoms such as shortness of breath, fatigue, and peripheral edema
- The need for medical management of heart failure symptoms or surgical valve repair or replacement when symptoms become severe
- The importance of preventing further valve damage through antibiotic prophylaxis and prompt treatment of group A streptococcal infections 1.
In terms of treatment, the goal is to reduce the pressure and volume overload on the heart, improve symptoms, and prevent further valve damage. This can be achieved through a combination of medical and surgical interventions, including valve repair or replacement, and medical management of heart failure symptoms 1.
From the Research
Rheumatic Heart Disease and Volume or Pressure Overload
- Rheumatic heart disease (RHD) is often associated with mitral regurgitation (MR), which can lead to volume overload 2.
- The development of secondary MR in RHD may be triggered by longstanding volume overload with left atrial (LA) remodeling 2.
- Predictors of MR progression in RHD patients include age and LA volume, suggesting a link between primary MR and secondary MR in patients with RHD 2.
- Medical management of RHD can encompass treatments for left ventricular dysfunction, rate control in mitral stenosis, and anticoagulation, which may help reduce symptoms and improve left ventricular function, but do not alter disease progression 3.
- Mitral valve repair and replacement are surgical options for RHD, with mitral valve repair not associated with superior long-term outcomes and a higher reoperation rate 4.
Volume Overload in RHD
- Volume overload is a common feature of RHD, particularly in patients with mitral regurgitation 2.
- LA enlargement may play a role in the link between primary MR and secondary MR in patients with RHD 2.
- The incidence of MR progression in RHD patients is predicted by age and LA volume, highlighting the importance of volume overload in the disease 2.
Pressure Overload in RHD
- Pressure overload is also a feature of RHD, particularly in patients with mitral stenosis 5.
- Mitral stenosis can lead to increased pressure in the left atrium, which can result in LA remodeling and volume overload 5.
- The management of RHD in patients with mitral stenosis often involves rate control and anticoagulation to reduce the risk of complications 3.