REVERSIBLE DIASTOLIC DYSFUNCTION AFTER SUCCESSFUL CORONARY-ARTERY BYPASS-SURGERY - ASSESSMENT BY TRANSESOPHAGEAL DOPPLER-ECHOCARDIOGRAPHY

To assess the potential effects of coronary artery bypass surgery on l eft ventricular diastolic filling, 12 patients, aged 65 +/- 11 years, were studied by serial transesophageal Doppler echocardiograms, Dopple r measures of mitral inflow velocity were made before, immediately aft er, 4 h after, and 20 h after cardiopulmonary bypass (CPB). Left atria l pressure was directly measured and controlled at 10 +/- 2 mm Hg for each study period. Mitral maximal early inflow velocity (E)/maximal at rial velocity (A) ratios and atrial filling fractions were calculated as indexes of diastolic function from maximal E and A velocities and t heir time velocity integrals, respectively. Data sets were available f or serial comparison in 11 patients and were also compared with an age -matched control group of normal values. The results of E/A ratios wer e as follows: control group-1.4 +/- 0.2; before CPB-1.7 +/- 0.6; immed iately after CPB-1.0 +/- 0.2 (p < 0.05 vs control group, before CPB, a nd 20 h after CPB values); 4 h after CPB-0.8 +/- 0.2 (p < 0.05 vs cont rol group, before CPB, and 20 h after CPB values); and 20 h after CPB- 1.3 +/- 0.4. Atrial filling fractions were as follows: control group-0 .29 +/- 0.05; before CPB-0.25 +/- 0.08; immediately after CPB-0.43 +/- 0.07 (p < 0.05 vs control group, before CPB, and 20 h after CPB value s); 4 h after CPB, 0.46 +/- 0.07 (p < 0.05 vs control group, before CP B, and 20 h after CPB values); and 20 h: after CPB-0.35 +/- 0.06. Alte rations in Doppler indexes of left ventricular filling occurred immedi ately after CPB and persisted 4 h after CPB. These indexes returned to baseline values by 20 h after CPB. This suggests reversible diastolic dysfunction in patients after coronary artery bypass surgery.