From the Research
The Valsalva maneuver typically increases the intensity of tricuspid regurgitation (TR) murmurs during the strain phase. This is because when a patient performs the Valsalva maneuver by bearing down against a closed glottis, there is increased intrathoracic pressure which reduces venous return to the right heart. During the strain phase, the decreased right ventricular preload initially reduces the intensity of the TR murmur, but as the strain continues, the increased right atrial pressure relative to right ventricular pressure enhances the regurgitant flow across the tricuspid valve, thereby augmenting the murmur.
Key Points to Consider
- The TR murmur is typically heard best at the left lower sternal border or xiphoid area and is characterized as a holosystolic, high-pitched, blowing murmur that increases with inspiration (Carvallo's sign) 1.
- When auscultating for TR, having the patient in a supine or left lateral decubitus position can help accentuate the murmur.
- The Valsalva maneuver serves as a valuable bedside tool for differentiating between various cardiac murmurs, with the response of TR being particularly distinctive due to its relationship with right-sided hemodynamics.
- Recent studies have shown that treatment of TR can have a positive impact on cardiac death and HF hospitalization at 1 year, as well as significant improvement in clinical and echocardiographic status at follow-up 1.
Mechanism of the Valsalva Maneuver
The Valsalva maneuver is an autonomic test that evokes short sharp cardiovascular fluctuations mediated by the autonomic nervous system 2. The increase in intrathoracic pressure that occurs during the Valsalva maneuver incites a sequence of rapid changes in preload and afterload stress. During the strain, venous return to the heart is decreased and peripheral venous pressures become increased.
Clinical Implications
The Valsalva maneuver is a useful tool in clinical practice for assessing TR and differentiating it from other cardiac murmurs. By understanding the mechanism of the Valsalva maneuver and its effects on TR, clinicians can better diagnose and manage patients with this condition, ultimately improving morbidity, mortality, and quality of life outcomes.