[Real-time coronary blood flow measurement in patients with atrial fibrillation: a study using a catheter-tip Doppler velocimeter].

To clarify the influence of changes in the cardiac cycle length (R-R) and aortic pressure on the coronary blood flow, a catheter-tip Doppler velocimeter was applied for 16 patients with chronic atrial fibrillation (11 with valvular heart disease, 2 with coronary artery disease, 2 with cardiomyopathy and one with atrial septal defect). An area under the coronary flow velocity curve during systole (integral of S), diastole (integral of D) and one cardiac cycle (integral of T) for the proximal portion of the left anterior descending artery (LAD: 12 cases) or the right coronary artery (RCA: 10 cases) was calculated in beat-by-beat. Then, the correlations between each area and the R-R, systolic period (S), diastolic period (D) and aortic pressure were assessed. In both the LAD and RCA, prolongation of R-R associated with prolonged D increased integral of D, which caused an increase of integral of T. Integral of D correlated with D (p < 0.05), but integral of S did not correlate with S, and the degree of change in integral of S or S was much less than that in integral of D or D. R-R or D of the preceding beat correlated inversely (p < 0.05) with integral S in 11 of 12 LAD cases. In the RCA, positive correlations between R-R or D of the preceding beat and integral of S were observed in cases with mitral stenosis (n = 6) or coronary heart disease (n = 1), but not in other cases; a case with aortic regurgitation or hypertrophic cardiomyopathy, negative, and dilated cardiomyopathy, no correlation.(ABSTRACT TRUNCATED AT 250 WORDS)