Influência do isoflurano na contratilidade miocárdica e fluxo coronariano de cora？？es isolados de ratos

eighteen adult rat hearts were studied by langendorff's technique under krebs-henseleit solution perfusion (90 ± 10 cm of h2o pressure, 36.5 ± 0.5°c temperature). nine rats were assigned to two groups: group i - control group and group ii - isoflurane group. hearts in group ii were treated with isoflurane at 1.5%. after stabilization during 15 minutes, initial values were obtained (t0), the next parameters were registered over the following periods: 1, 2, 4, 6, 10 minutes, respectively. there were no statistically significant variations in systolic pressure nor in dp/dt (p > 0.05) in period t1 in both groups. an increase was observed in diastolic pressure, statistically significant in group ii (4.8 mmhg - t0 period; 12.8 mmhg - t1 period). there was a decrease in heart rate and increase in coronary flow in group ii, statistically significant(p < 0.05), one minute after drug infusion. the coronary flow decreased progressively in every recovery period (t2 t0 t5) in group ii (p < 0.05). during the same periods there were no statistically significant variations in group i. isoflurane increases coronary flow during its administration, decreasing it during the recovery periods; it decreases heart rate, increases diastolic pressure and shows evidence of myocardial contractility depression in isolated rat hearts.