THE IMPACT OF ISCHEMIC-HEART-DISEASE ON MAIN PULMONARY-ARTERY BLOOD-FLOW PATTERNS - A COMPARISON BETWEEN MAGNETIC-RESONANCE PHASE-VELOCITY MAPPING AND TRANSESOPHAGEAL COLOR DOPPLER

Objective: To give a detailed evaluation on main pulmonary artery bloo d velocity patterns, in patients with ischemic heart disease and to pr ovide recommendations for pulsed Doppler sample Volume placement, in o rder to optimize cardiac output estimation. Methods: Using magnetic re sonance phase and esophageal color Doppler velocity mapping in 12 pati ents with ischemic heart disease and undergoing coronary artery by-pas s grafting, very similar data on pulmonary artery blood velocity patte rns were provided for comparison with each other. Results: Peak blood velocities were located in the inferior half of the main pulmonary art ery cross-sectional area. Early after peak systole the highest velocit ies shifted towards the superior/left (major curvature) with a simulta neous decrease in velocities inferiorly. The velocity decrease further evolved into retrograde flow to the inferior/right (minor curvature). This feature was significantly enhanced compared to earlier findings in healthy volunteers. The mean temporal blood velocity profiles were asymmetrically skewed, thereby giving unreliable cardiac output estima tes based on single point Doppler blood velocity recordings. The error incurred may amount to more than 100% in extreme cases. According to our data, optimal assessment of cardiac output should be based on mult iple sample volumes placed along the inferior/right to superior/left d iameter. Conclusions: MR-phase velocity mapping and multiplane transes ophageal color Doppler recordings provided similar blood velocity patt erns in patients with ischemic heart disease. The skewness of the mean temporal blood velocity profile is enhanced compared with healthy sub jects, resulting in error in the assessment of CO by means of pulsed D oppler echocardiography. By using multiple Doppler sample volumes, the error can be minimized. (C) 1997 Elsevier Science B.V.