RESUMEN
INTRODUCTION AND OBJECTIVES: The late reocclusion or restenosis rate of the infarct related artery is frequent after primary angioplasty. An implanted stent may be able to improve the coronary angioplasty results and long-term outcome of these patients. We present the clinical and angiographic outcome of a cohort of patients treated with primary stenting. PATIENTS AND METHODS: A group of 74 consecutive patients with acute myocardial infarction treated with primary angioplasty and stenting were followed for one year. An angiographic control was performed at the 6th month of follow-up in 91% of patients to assess the restenosis and reocclusion rates of the infarct-related artery. RESULTS: There were eight in-hospital deaths and three during follow-up (mortality rate 14.8%) and one non-fatal reinfarction (1.5%). The cumulative rate of recurrent ischemia was 6% at 3 months and 15% at 6 months, without any further increment at one-year follow-up. A new angioplasty was performed in 7 patients and three patients underwent surgical revascularization. Thus 80% of patients after discharge were free of events. The angiographic control showed only one reocclusion of the infarct related artery and a restenosis rate of 27%. CONCLUSIONS: These results show that primary stenting is an effective procedure in treating non-selected patients with acute myocardial infarction with a low long-term incidence of adverse events and a low restenosis rate.
Asunto(s)
Infarto del Miocardio/cirugía , Stents , Enfermedad Aguda , Fibrinolíticos/uso terapéutico , Estudios de Seguimiento , Oclusión de Injerto Vascular , Humanos , Infarto del Miocardio/terapiaRESUMEN
INTRODUCTION AND OBJECTIVES: There are not any conclusive data about the changes in in-hospital mortality in a non-selected series of patients admitted with acute myocardial infarction in different periods of time. We studied the in-hospital mortality of three extensive series of patients admitted to our Coronary Care Unit during different periods of time, the influence of reperfusion methods and their early application, as well as the changes in baseline characteristics of the three populations studied. METHODS: The in-hospital mortality of 1,858 consecutively-admitted patients during three different periods of time (1983-1986, 1992-1994, and 1995-1998) were studied. The demographic data, the previous history and risk factors, the evolution during the acute phase and the treatment prescribed with special attention to the reperfusion methods applied and the delay on its administration were compared. RESULTS: The differences in the baseline characteristics of the populations studied are described. In the two groups of the nineteen-nineties, an increase in the age and in the percentage of women, diabetics and hypertensives was compared. As for the characteristics of acute myocardial infarction, an increase of patients in Killip class 3 and 4 stands out besides other changes. Fibrinolitic treatment decreased during the third period due to the increment in primary angioplasty. There were no significant differences in hospital mortality among the three series studied. The treatment with thrombolysis and primary angioplasty during the first two hours showed a significant independent reduction of mortality. CONCLUSIONS: The early application of thrombolysis and primary angioplasty showed an independent reduction of the hospital mortality in our study. Nevertheless the non-adjusted mortality rate did not show any change during the last 15 years.
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Infarto del Miocardio/mortalidad , Infarto del Miocardio/terapia , Reperfusión Miocárdica , Anciano , Femenino , Hospitalización , Humanos , Masculino , Persona de Mediana Edad , España/epidemiología , Terapia TrombolíticaRESUMEN
INTRODUCTION AND OBJECTIVES: Stent implantation has been generally contraindicated during primary percutaneous transluminal balloon angioplasty in AMI, because of its possible trombogenicity. Report the early outcome of patients undergoing coronary stenting during primary PTCA. METHODS: From january 1995 to april 1996, 31 patients underwent stent implantation in primary. Mean age 62 +/- 11 years. Infarct location was anterior in 20 (65%), and inferior in 11 patients (35%). Four patients were in Killip class IV. Mean onset of chest pain was 129 +/- 29 minutes. Indications for stenting were suboptimal result (64%), dissection (29%) and elective (6%). All patients were treated with heparin during 72 hours and antiplatelet therapy with ticlopidine and aspirin. RESULTS: Coronary stenting restored vessel patency with TIMI 3 flow in 29 patients (94%) and TIMI 2 flow in 2 patients. Angiographic control was performed in 80% of the patients: no stent occlusion was observed and all patients showed a TIMI 3 flow. There were 3 deaths (9%): 2 patients died due to cardiogenic shock and 1 to severe right ventricular dysfunction. 2 patients (6%) had recurrent angina, due to other artery. One patient with left main coronary disease underwent elective coronary artery bypass graft surgery. CONCLUSIONS: Intracoronary stent can be used successfully during primary angioplasty with a low incidence of complications. The long term benefits remains to be established.
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Infarto del Miocardio/cirugía , Stents , Adulto , Anciano , Anciano de 80 o más Años , Angiografía Coronaria , Vasos Coronarios , Femenino , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/diagnóstico por imagenRESUMEN
INTRODUCTION AND OBJECTIVES: In previous studies we have observed ischemic processes of very brief duration (2 minutes) and with brief reperfusion (3 minutes), which have been repeated 20 times (ischemic protocol [IP]). They are capable of producing contractile dysfunction of the ischemic zone, with a decrease of 28.6% at 24 hours, and coronary blood flow maintenance (stunning). METHODS: The aim of this study is to examine the evolution of this dysfunction. The IP designed in our laboratory was used on 24 adult mongrel dogs. We measured regional myocardial function using a pair of implanted chronic ultrasonic crystals in the ischemic area (depending on the left anterior descending coronary artery) and a second pair in the control zone (depending on the left circumflex coronary artery). RESULTS: After analyzing results, we found that the shortening fraction decreased to 28.6% (p < 0.05) in 24 hours. During the subsequent five days the shortening fraction decreased to a minimum of 67.88% (p < 0.01), after which there was a progressive recovery that reached 18.95% (NS) below the base-line on the tenth day. We did not observe any significant variation in the hemodynamic parameters at any time. CONCLUSIONS: The repeated, very brief episodes of ischemia (in the experimental terms that we have explained) produced a contractile dysfunction which reached its maximum on the fifth day, and returned to normal on the tenth day. We hypothesize that these alterations could explain the episodes of left ventricular failure with spontaneous recuperation observed in stable myocardial ischemia, and for which no immediate cause has been found.
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Aturdimiento Miocárdico/fisiopatología , Animales , Modelos Animales de Enfermedad , Perros , Femenino , Hemodinámica , Masculino , Isquemia Miocárdica , Factores de TiempoRESUMEN
OBJECTIVE: To analyze whether nitroglycerin and nifedipine can reduce myocardial stunning due to very brief, repeated coronary ischemias. MATERIAL AND METHODS: In 33 anaesthetized and open chest dogs, the lengthening and shortening fractions were analyzed with ultrasonic crystals in the ischemic and control myocardial areas. Twenty repeated coronary occlusions of 2 minutes each, with a recovery time of 3 minutes between each occlusion, were induced. At the beginning of the experiment, nitroglycerin (0.3 mg i.v. and 80 micrograms/kg/min perfusion) was administered in series A (n = 8), nifedipine (5 mu/kg i.v. and 1 microgram/kg/min perfusion) in series B (n = 9). The results were compared with control results (n = 16) without drugs. RESULTS: Changes in the shortening fraction of the ischemic area during coronary occlusions were similar in all three series; after the last occlusion the shortening fraction in the control series was -14.9% with respect to basal values, -14.6% in series A and -16.6% in series B. Sixty minutes after the last ischemia, the shortening fraction impairment in respect to the basal values was larger in the control series (-18.9%) and in series A (-16.9%). In series B there was recovery (-13.5%) (p < 0.05 vs control series). CONCLUSIONS: Our study indicates that nitroglycerin does not seem to have cardioprotective effects against brief, repeated ischemia. However, nifedipine decreases postischemic dysfunction due to this model of ischemia, probably by avoiding the intracellular Ca overload produced during cardiac ischemia.