Multivalvular heart disease, also known as combined valvular disease, is the simultaneous involvement of two or more heart valves.
Etiology
The causes of multivalvular heart disease are mostly due to a single underlying condition, though in some cases, multiple causes may coexist.
A Single Disease Affecting Multiple Valves
The most common cause is rheumatic heart disease, with nearly half of the patients having multiple valve involvement. Other causes include age-related degenerative changes and myxomatous degeneration, which can simultaneously affect the mitral and tricuspid valves, both of which may prolapse. Infective endocarditis can also involve multiple valves.
Hemodynamic Abnormalities caused by One Valve Lesion leading to Secondary Involvement of Adjacent Valves
For example, aortic regurgitation can cause left ventricular volume overload and dilation, resulting in secondary mitral regurgitation.
Different Diseases Affecting Different Valves
For instance, congenital pulmonary valve stenosis can be in combination with rheumatic mitral valve disease.
Pathophysiology and Clinical Manifestations
The pathophysiology and clinical presentation depend on the combination of valve lesions and the relative severity of each lesion. While one valve lesion may mitigate or offset the hemodynamic effects of another, reducing clinical symptoms, multivalvular disease generally exacerbates the overall condition and imposes a cumulative adverse impact on cardiac function.
Common combinations of multivalvular heart disease include:
- Mitral stenosis with aortic regurgitation
- Mitral stenosis with aortic stenosis
- Aortic stenosis with mitral regurgitation
- Mitral regurgitation with aortic regurgitation
- Mitral stenosis with tricuspid and/or pulmonary valve regurgitation
Mitral Stenosis with Aortic Regurgitation
It is commonly seen in rheumatic heart disease. Mitral stenosis can delay left ventricular dilation, resulting in less prominent peripheral vascular signs. The diastolic murmur of mitral stenosis may be diminished or even absent.
Mitral Stenosis with Aortic Stenosis
If mitral stenosis is more severe than aortic stenosis, the latter’s manifestations may be masked. Left ventricular filling becomes restricted, and left ventricular systolic pressure is reduced, delaying left ventricular hypertrophy and reducing myocardial oxygen demand, which may result in less prominent angina.
Due to significantly reduced cardiac output, the transvalvular pressure gradient across the aortic valve may be underestimated, leading to an underestimation of aortic stenosis severity.
Aortic Stenosis with Mitral Regurgitation
This is a dangerous combination but relatively uncommon. Aortic stenosis exacerbates mitral regurgitation, while mitral regurgitation reduces the preload required to maintain stroke volume in aortic stenosis. This results in early pulmonary congestion and rapid onset of left heart failure.
Mitral Regurgitation with Aortic Regurgitation
The left ventricle experiences a dual volume overload, leading to a significant rise in left ventricular diastolic pressure. This can further worsen mitral regurgitation and result in early left ventricular failure.
Mitral Stenosis with Tricuspid and/or Pulmonary Valve Regurgitation
They are commonly seen in patients with advanced rheumatic heart disease and mitral stenosis.
Diagnosis
Careful evaluation is essential for diagnosing multivalvular heart disease. Echocardiography plays a critical role in diagnosis and functional assessment.
When necessary, left and right heart catheterization can be performed for detailed evaluation of valve function.
Treatment
Medical management is similar to that for single valve lesions.
Surgical intervention is the primary treatment option. However, double valve replacement carries a higher risk of perioperative and long-term mortality compared to single valve replacement.
A thorough analysis of the benefits and risks for each valve should be conducted before surgery.
For patients who are not candidates for surgical intervention, staged percutaneous interventions may be considered.