The Second Department of Internal Medicine, Faculty of Medicine, University of Tokushima
Continuous wave Doppler echocardiography, Pulmonary hypertension, Diastolic tricuspid regurgitation, Relaxation abnormality of the right ventricle
To investigate the characteristics and clinical significance of tricuspid regurgitation (TR) in pulmonary hypertension (PH), we analysed tricuspid regurgitant flow signal recorded by continuous wave Doppler echocardiography (CW) in 36 patients with various heart diseases. The patients were classified into four groups on the basis of right ventricular systolic pressure (RVSP) estimated indirectly from the formula of 4V²+10 (mmHg), where V indicated maximum velocity of TR obtained by CW method. No significant differences were found in heart rate, total electro-mechanical systole of the right ventricle and systolic duration of the TR signal (s-TR), which is the interval from the onset of TR signal to the pulmonic component (P2) of the second heart sound, among the four groups. However, diastolic duration of the TR signal (d-TR), which is the interval from the P2 to the end of TR signal, was prolonged proportionately with the severity of PH. A significant correlation was found between the RVSP and the ratio of diastolic to total duration of TR signal (r=0.79, p2 about 66 msec, but all of the 29 patients with moderate, mild and no PH showed the regurgitant murmur within the systolic phase. These abnormalities on diastolic phenomenon of the tricuspid regurgitant signal are thought to be caused mainly by the disturbed relaxation of the right ventricle. We conclude that the duration and configuration of the diastolic component of tricuspid regurgitation recorded by the CW method may be a useful index for the clinical evaluation of the severity of pulmonary hypertension and/or early diastolic property of the right ventricle.