RESUMEN
Although experimental evidence has demonstrated that brief periods of myocardial ischemia are not associated with norepinephrine overflow from the heart, cardiac sympathetic responses to myocardial ischemia in humans remain unclear. Eleven patients undergoing angioplasty of the left anterior descending coronary artery had cardiac norepinephrine spillover measured immediately before inflation, during the final minute of a 5-min balloon inflation, and 1 min after deflation. Angioplasty caused significant S-T segment elevation and a reduction in the transcardiac lactate extraction ratio. Cardiac norepinephrine spillover was reduced from a mean value of 58 +/- 14 pmol/min at control to 41 +/- 15 pmol/min during balloon inflation and 38 +/- 14 pmol/min after deflation (P < 0.05 vs. control for both inflation and deflation values). In contrast, during balloon inflation, there were significant increases in arterial norepinephrine and epinephrine concentrations. Therefore, a brief period of myocardial ischemia caused by angioplasty of the left anterior descending coronary artery does not result in cardiac sympathetic activation, despite evidence of generalized sympathoadrenal activation.
Asunto(s)
Isquemia Miocárdica/fisiopatología , Norepinefrina/metabolismo , Sistema Nervioso Simpático/fisiología , Angioplastia de Balón , Presión Sanguínea , Circulación Coronaria , Femenino , Frecuencia Cardíaca , Humanos , Masculino , Persona de Mediana EdadRESUMEN
Intracoronary stenting as a transcatheter treatment for bifurcation stenoses remains controversial. A novel technique of coronary bifurcation stenting is reported. A 15 mm Palmaz-Schatz stent is bent 180 degrees at its bridge articulation into a V- configuration and mounted on two balloon-catheters linked together by adhesive tape. This unified stent delivery system was used successfully in five cases of porcine coronary bifurcation stenting.