RESUMEN
INTRODUCTION: Numerous reports on the inducibility of ventricular tachyarrhythmias (VT) in patients with atypical right bundle branch block and right precordial ST-elevation (Brugada syndrome) are based on multicentre studies that have used different stimulation protocols. Therefore, we prospectively investigated the inducibility of VT in these patients using a uniform protocol. METHODS: In 41 consecutive patients (29 males) showing a pattern of right bundle branch block and ST-elevation, programmed ventricular stimulation was performed in the right ventricular apex with up to three premature stimuli at sinus rhythm and at four different paced cycle lengths (500, 430, 370, and 330 ms) until refractoriness was reached or reproducible induction of a sustained (>30s) VT occurred. If a VT was not reproducibly inducible, the same protocol was repeated in the right ventricular outflow tract. RESULTS: A history of life-threatening events defined as syncope (n=17) or aborted sudden cardiac death (n=13) was present in 30 patients (73%); 11 individuals were asymptomatic. Inducibility (68%) was similar between symptomatic (n=21, 70%) and asymptomatic patients (n=7, 64%). In 16 (39%) patients, VT were reproducibly inducible. If patients were only stimulated in the right ventricular apex, inducibility rate decreased to 39%. If only two premature beats at two sites were used it was as low as 32%. The mean coupling intervals of the second and third premature stimuli inducing sustained VT were short: 189+/-21 ms vs 186+/-22 ms, respectively. Forty-four percent of all patients (i.e. 64% of the inducible patients) had inducible VT only with coupling intervals shorter than 200 ms. CONCLUSIONS: The stimulation protocol markedly influences the extent of inducibility of VT in patients with right bundle branch block and ST-segment elevation. These findings question the significance of previous multicentre studies using different stimulation protocols and should have implications for further studies.
Asunto(s)
Bloqueo de Rama/fisiopatología , Taquicardia Ventricular/fisiopatología , Adulto , Anciano , Desfibriladores Implantables , Electrocardiografía , Técnicas Electrofisiológicas Cardíacas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Síndrome , Fibrilación Ventricular/fisiopatologíaRESUMEN
CASE REPORT: After administration methylergometrine 30 minutes after delivery for peripartal vaginal bleeding a 31-year-old female patient developed an acute anterior wall myocardial infarction. Coronary angiography 7 hours after beginning of the chest pain demonstrated a dissection with a large thrombus in the proximal left anterior descending artery, followed by a complete occlusion in the periphery of the vessel (Figure 1). After applying rtPA intravenously, coronary angiography showed 24 hours later an open vessel without thrombotic material (Figure 2). CONCLUSION: Coronary artery spasm induced by methylergometrine must be regarded as the main reason for the dissection and thrombus formation followed by a myocardial infarction.
Asunto(s)
Vasoespasmo Coronario/inducido químicamente , Metilergonovina/efectos adversos , Infarto del Miocardio/inducido químicamente , Hemorragia Posparto/tratamiento farmacológico , Adulto , Angiografía Coronaria , Trombosis Coronaria/inducido químicamente , Trombosis Coronaria/diagnóstico , Vasoespasmo Coronario/diagnóstico , Femenino , Humanos , Inyecciones Intramusculares , Metilergonovina/administración & dosificación , Infarto del Miocardio/diagnóstico , Factores de RiesgoRESUMEN
BACKGROUND: We assessed the impact of patient and procedural characteristics on the outcome after emergency coronary artery bypass grafting (CABG) for failed percutaneous transluminal coronary angioplasty (PTCA) and temporal changes in these factors. METHODS: Patients who underwent PTCA and subsequent emergency CABG were identified from the databases of the Departments of Cardiology and Cardiothoracic Surgery. RESULTS: Two periods of clinical practice were compared. In 1989 to 1993, 2,880 PTCAs were performed, 64 patients underwent emergency CABG (2.3%), and 7 patients died (10.9%). During 1994 to 1998, 46 patients of 3,801 PTCAs underwent emergency CABG (1.2%, p < 0.01), and 7 patients died (15.2%, NS). The average rate of stenting increased from 0.8% to 24% in 1994 to 1998 as well as the frequency of arterial bypass grafts (0% vs 39%). In the latter period, patients were older, were more often females, had more cardiovascular risk factors, a higher Cleveland score (each p < 0.05), and suffered more often from periprocedural myocardial infarctions (p < 0.001) and nonfatal periprocedural complications (p < 0.01). CONCLUSIONS: Although the frequency of emergency CABG after failed PTCA declined, perioperative mortality tended to increase according to an unfavorable shift in patient risk factors and morbidity.