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Excessive respiratory variation in tricuspid regurgitation systolic velocities in patients with severe tricuspid regurgitation.

AIMS
Respiratory changes in tricuspid regurgitation (TR) systolic velocities are occasionally demonstrated by Doppler echocardiography in patients with TR. We tested the hypothesis that excessive respiratory changes in TR velocities are diagnostic of severe TR.


METHODS AND RESULTS
The difference between the maximal (expiratory) and minimal (inspiratory) TR systolic velocities during spontaneous respiration was measured by Doppler echocardiography in 68 patients with severe TR and 68 patients with moderate TR. The diagnostic value of the respiratory changes in TR velocity for detecting severe TR was assessed. The respiratory differences in TR velocities were greater in patients with severe TR (0.72 ± 0.30 m/s), compared with patients with moderate TR (0.28 ± 0.18; P < 0.001). Using receiver-operating characteristics analysis, the area under the curve for the respiratory difference in TR velocities for diagnosing severe TR was 0.92 (95% confidence interval: 0.87-0.96; P < 0.001). A difference in TR velocity ≥0.6 m/s had a sensitivity of 66%, specificity of 94%, positive predictive value of 92%, and a negative predictive value of 74% for diagnosing severe TR. Among patients with severe TR, excessive values of TR velocity difference were associated with signs of more severe TR (greater right ventricular size and malcoaptation of the tricuspid valve leaflets).


CONCLUSION
Excessive respiratory changes in Doppler measurements of TR systolic velocities are a specific sign of severe TR.