From the Guidelines
The Valsalva maneuver typically decreases the intensity of the diastolic murmur heard in mitral stenosis. This effect is due to the decreased venous return to the heart during the strain phase of Valsalva, which reduces left atrial filling and subsequently diminishes the pressure gradient across the stenotic mitral valve, as described in the 2008 guidelines for the management of patients with valvular heart disease 1.
Key Points
- The Valsalva maneuver decreases the intensity of most cardiac murmurs, including mitral stenosis, with a few exceptions such as hypertrophic cardiomyopathy and mitral valve prolapse 1.
- The decreased venous return during Valsalva reduces left atrial filling, resulting in a softer murmur as less blood flows through the narrowed valve opening.
- The characteristic low-pitched, rumbling diastolic murmur of mitral stenosis becomes less audible during the Valsalva maneuver.
- After release of the Valsalva strain, there is a transient increase in venous return, which may briefly intensify the murmur before it returns to baseline.
Clinical Implications
- Understanding the physiologic response to Valsalva is valuable during cardiac auscultation to help confirm the diagnosis of mitral stenosis and distinguish it from other cardiac pathologies.
- The response to Valsalva can be used to differentiate mitral stenosis from other cardiac conditions like hypertrophic cardiomyopathy, where the murmur typically increases during strain 1.
From the Research
Effect of Valsalva Maneuver on Mitral Stenosis Murmur
- The Valsalva maneuver is used to aid in the diagnosis of various heart conditions, including mitral stenosis 2.
- However, the provided studies do not directly address the effect of the Valsalva maneuver on the murmur of mitral stenosis.
- One study discusses the use of bedside maneuvers, including the Valsalva maneuver, in evaluating patients with systolic murmurs, but it does not specifically address mitral stenosis, which is typically associated with a diastolic murmur 3.
- Another study explains the physiological principles behind the Valsalva maneuver and its effects on cardiac parameters, but it does not provide information on its specific effect on mitral stenosis murmur 4.
- The other studies focus on the mechanisms and clinical implications of the Valsalva maneuver 5, its effect on blood pressure 6, and its use in echocardiography 2, but they do not provide direct evidence on its effect on mitral stenosis murmur.