RESUMEN
UNLABELLED: Modifications of left ventricular isometric relaxation time (LVIRT) were analyzed in an experimental model of myocardial reperfusion (MR). In a prospective study, 19 mongrel dogs were studied with open chest, mechanical ventilation and hemodynamic monitoring. A catheter was inserted in the middle third of the anterior descending artery (ADA) for registry of its pressure. The ADA was ligated distal to the first diagonal branch for 15 min and subsequently untied. Epicardial Echo/Doppler registries were obtained in basal conditions, at 5 and 15 min of ischemia and at 5, 15, 30 and 60 min after MR. Mobility and changes in thickness of the interventricular septum (IVS) were analyzed, and LVIRT was measured in all of the periods mentioned. There were no significant changes in the thickness of IVS. LVIRT increased in comparison to the basal registry at 5 and 15 min of ischemia (p < 0.0001) and returned to basal values with MR (p < 0.05). CONCLUSIONS: Acute myocardial ischemia prolongs LVIRT, in this model, during MRLVIRT returned to normal. In the experimental model, measurement of LVIRT may be used as criterion for reperfusion.
Asunto(s)
Ecocardiografía Doppler , Contracción Miocárdica , Isquemia Miocárdica/fisiopatología , Reperfusión Miocárdica , Función Ventricular Izquierda , Animales , Perros , Frecuencia Cardíaca , Contracción Isométrica , Estudios ProspectivosRESUMEN
Previous reports suggest that morbidity and mortality post acute myocardial infarction (AMI) are increased in patients with non-insulin-dependent diabetes (NIDDM). To obtain information in our population related to the prognosis after an AMI in diabetic patients and its major determinants, we studied 96 NIDDM patients admitted consecutively with a diagnosis of AMI. We used a control group (CG) of age and sex matched non-diabetic individuals. Patients with NIDDM had more frequently a history of angina (40 vs 23%, p < 0.001) and previous MI (30 vs 15%, p < 0.05). The AMI localization and extension, and the presence of arrhythmias were similar for both groups. Early mortality after the AMI was 22% in the NIDDM group and 12% in the CG with Odds ratio of 1.9 (CI 95% 0.91-5.15), being higher in diabetic females [2.3 (CI 95% 0.77-14.6) vs female CG and 1.5 (CI 95% 0.8-7.6) vs male NIDDM]. Extended MIs predicted higher mortality rate, especially among NIDDM patients (p < 0.05). Stepwise logistic regression test supported diabetes mellitus, per se, as a major contributor for mortality (p < 0.02), followed by MI localization and extension. The worst outcome was in NIDDM female patients of advanced age and hypertensive (p < 0.00001).