for the TAUSA Investigators Background Acute closure is increased after angioplasty in unstable angina, and adjunctive intracoronary thrombolytic therapy has been used successfully to increase angiographic success. The role of prophylactic thrombolytic therapy during angioplasty in unstable angina is unknown.Methods and Results Four hundred sixty-nine patients with ischemic rest pain with or without a recent (<1 month) infarction were randomized in double-blind fashion to intracoronary urokinase or placebo. Randomization was carried out in two sequential phases. In phase I, 257 patients were randomized to 250 000 U of urokinase or placebo given in divided doses at the time of angioplasty. In phase II, 212 patients were randomized to 500 000 U of urokinase or
Complex lesions before coronary angioplasty increase acute complication rates after coronary angioplasty. Urokinase as administered in the TAUSA trial had significant adverse effects, especially in complex lesions. However, even in the placebo arm, complex lesions were associated with higher complication rates than simple lesions. Newer antithrombotic measures that particularly target the platelet may eventually decrease complication rates in these lesions.
The opening of the tricuspid valve and the onset of right ventricular filling precede the opening of the mitral valve and the onset of flow in the normal adult. Sixty-five studies of atrioventricular flow with range-gated pulsed Doppler echocardiography, performed on 32 normal neonates, consistently demonstrated the reverse sequence. Further investigation showed that at the time of mitral valve opening, while the tricuspid valve was still closed, the valve of the foramen ovale began to bow posteriorly into the left atrium and remained posteriorly bowed for most of diastole. The magnitude of posterior bowing varied among the neonates but, concomitant with the more prominent grades of posterior bowing, right to left shunting across the foramen ovale was demonstrated on color flow mapping. Ultrasound studies in the normal fetus also revealed earlier opening of the mitral valve, bowing of the valve of the foramen ovale into the left atrium and right to left shunting across the foramen ovale. These findings indicate that in the normal immature heart isovolumic ventricular relaxation is completed earlier on the left than on the right side and that left ventricular compliance appears to be greater than right ventricular compliance. The relation of left and right ventricular compliance in the adult is different from that in the normal immature heart. Whereas systemic and pulmonary vascular resistance and pressure levels change rapidly in the newborn period, ventricular compliance matures over a longer period of time. As a result of the differential maturity, for a variable period of time in the normal neonate, a left to right ductal shunt coexists with a right to left atrial shunt.
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