Right ventricular myocardial isovolumic relaxation time and pulmonary pressure -: Pulsed Doppler tissue imaging in resurrection of Burstin's nomogram

Aims: Non-invasive assessment of pulmonary artery systolic pressure (PASP) has several limitations. As previously described by Burstin, the right ventricular (RV) isovolumic relaxation time (IVRt) is sensitive to changes in PASP. We therefore compared RV myocardial IVRt, derived by Doppler tissue imaging (DTI), with simultaneously measured invasive PASP. Methods and results: Twenty-six consecutive patients (18 males, mean age 5 +/- 12 years, range 23-75) underwent a simultaneous Doppler echocardiography, including DTI, and cardiac catheterization examination for measurement of PASP and right atrial mean pressures. IVRt was measured using the myocardial velocities by pulsed DTI at both basal and mid cavity segments of the RV free wall. As diastolic time intervals are influenced by heart rate IVRt was corrected for heart rate (IVRt/ RR%). A significant correlation was found between PASP and regional IVRt/RR% at both the basal (r = 0 center dot 42, P < 0 center dot 05) and mid cavity segment (r = 0 center dot 71, P < 0 center dot 001). Furthermore, when only patients with normal right atrial pressures (< 7 mmHg) were taken into account, the correlation coefficient improved at both basal and mid cavity segments (r = 0 center dot 74, P < 0 center dot 05 and r = 0 center dot 83, P < 0 center dot 01). Conclusion: Pulsed Doppler-derived IVRt correlates well with PASP. The use of pulsed DTI for measurement of IVRt is simple, reproducible and easy to obtain. We propose this method as an additional non-invasive tool in the assessment of PASP.