[Evaluation of pulmonary regurgitation with a catheter-tip electromagnetic velocity probe]

Pulmonary regurgitation appeared after the surgical repair of pulmonary stenosis was investigated with an electromagnetic catheter-tip velocity probe in seven patients. Postoperative catheterization was performed by placing the probe in the pulmonary trunk transvenously and a velocity curve was recorded on a photographic recorder at a paper speed of 150 or 200 mm/sec with electrocardiograms and pulmonary arterial pressure pulse. The velocity curves were recorded under the baseline throughout diastole in patients with pulmonary regurgitation, while the curves in the normal controls were just on the baseline. The amount of regurgitation was evaluated with the ratio of the negative to positive area of velocity curves. The negative area (NA) was defined as an area circumscribed by the diastolic negative velocity curve and the baseline, and the positive area (PA) as an area circumscribed by the systolic positive curve and the baseline. The amount of the regurgitation was also evaluated from either the pulmonary cineangiogram or the volume measurement using the right arteriogram. The results were as follows: The severity of pulmonary regurgitation estimated by the pulmonary arteriogram (grade I to III) tended to be correlated with the ratio of the NA/PA. Right ventricular end-diastolic volume index (RVEDVI) and the NA/PA showed a fair correlation with a coefficient of 0.80. Right ventricular volume overload resulting from pulmonary regurgitation was reflected on the NA/PA. The subtraction of right and left ventricular systolic ejection indices (RVSI-LVSI) or its ratio (RVSI-LVSI)/RVSI, which were considered as the indices of the severity of pulmonary regurgitation from the volume measurement, had fairly good a correlation with the NA/PA.(ABSTRACT TRUNCATED AT 250 WORDS)