[Prognostic value of myocardial perfusion SPECT in multivessel coronary disease patients with left ventricular dysfunction, comparing revascularized and non-revascularized patients]. / Valor pronóstico del SPECT de perfusión miocárdica en pacientes coronarios con enfermedad multivaso y disfunción ventricular izquierda, comparando revascularizados y no revascularizados.

OBJECTIVE: We investigated the prognostic value of 99mTc-Tetrofosmin myocardial SPECT (99mTc-TF) in dysfunctional multivessel coronary disease patients who underwent revascularization (RV) or only medical treatment (MT). METHODS: In 78 coronary patients with 2-3 diseased vessels and left ventricular ejection fraction (EF) <= 40% (24 10%), we have assessed the extension of the stress perfusion defect, and percent of reversibility (R) by quantification of stress-rest myocardial SPECT 99mTc-TF bull's eyes (2 days-protocol), lung/heart ratio (LH) calculated in the original stress SPECT images, and EF by equilibrium radionuclide ventriculography obtained at 24 h. A R value >= 8% was used to identify viable (V) patients. A total of 28 patients underwent RV and 50 only received MT. After a mean follow-up of 22.9 20 months (3-60), they were considered as coronary events (CE): cardiac death, non-fatal infarction and heart transplant. CE rate was 20.5% (16/78). RESULTS: No significant differences were found in the pre-revascularization study characteristics, except a significantly higher mean R value in RV (10.6 9.5%) than in MT patients (6.4 7.8%) p: 0.03, and the main difference was that RV patients showed less CE 2/28 (7%) than the MT group 14/50 (28%) p: 0.02. The CE rate was lower in V patients who underwent RV (6%) than in V patients with MT (45%) p: 0.03, but no significant difference was obtained in non-V patients between RV (7%) and MT (16%) groups. In viable patients, the corresponding survival curves (Kaplan-Meier) showed a CE-free survival at 5 years of 79% in patients RV and of 42% in MT patients, p: 0.03, without significant difference in non-V patients. CONCLUSIONS: Patients with viable myocardium by myocardial SPECT have a good prognosis after revascularization, and show higher risk of CE if they are only medically treated. Myocardial viability is an indispensable assessment in prognosis evaluation and, above all, in therapeutic decision making in dysfunctional multivessel coronary disease patients.

Valor pronóstico del SPECT de perfusión miocárdica en pacientes coronarios con enfermedad multivaso y disfunción ventricular izquierda, comparando revascularizados y no revascularizados* / Prognostic value of myocardial perfusion spect in multivessel coronary disease patients with left ventricular dysfunction, comparing revascularized and non-revascularized patients

Objetivo: Investigamos el valor pronóstico del SPECT miocárdico con 99mTc-Tetrofosmin (99mTc-TF) en pacientes disfuncionales con coronariopatía multivaso, que sufrieron revascularización (RV) o fueron sometidos sólo a tratamiento médico (TM).Métodos: En 78 pacientes coronarios con 2-3 vasos afectos y fracción de eyección del ventrículo izquierdo (FE) 40 por ciento (24 ñ 10 por ciento) hemos valorado la extensión del defecto de perfusión de esfuerzo (E), el porcentaje de reversibilidad (R), mediante cuantificación del diagrama polar a partir del SPECT miocárdico de esfuerzo-reposo (protocolo 2 días), el índice pulmón/miocardio (P/M), calculado en las imágenes originales del SPECT de esfuerzo, y la FE, mediante ventriculografía isotópica de equilibrio, obtenida a las 24 h del SPECT. Se utilizó un valor de R 8 por ciento para identificar a los pacientes viables (V). Un total de 28 pacientes sufrieron RV (by-pass) y 50 recibieron sólo TM. Tras un seguimiento medio de 22,9 ñ 20 meses (3-60) se consideraron como accidentes cardíacos (AC): muerte cardíaca, trasplante cardíaco e IAM, que aparecieron en 16/78 (20,5 por ciento). Resultados: No se encontraron diferencias significativas en las características del estudio pre-revascularización, salvo una R media mayor en los RV (10,6 ñ 9,5 por ciento) que en los de TM (6,4 ñ 7,8 por ciento) p: 0,03, siendo lo principal la menor incidencia de AC en los RV, 2/28 (7,1 por ciento) que en los de TM, 14/50 (28 por ciento) p: 0,02. Hubo menor incidencia de AC en los pacientes V que fueron RV (6 por ciento) que en los pacientes V con TM (45 por ciento), p: 0,03, no siendo significativa la diferencia en los pacientes no V entre los RV (7 por ciento) y los de TM (16 por ciento). Se obtuvieron las correspondientes curvas de supervivencia (Kaplan-Meier), que mostraron, en los pacientes V, una probabilidad de supervivencia libre de AC a los 5 años del 79 por ciento en pacientes RV y del 42 por ciento en pacientes con TM, p: 0,03, sin ser significativas las diferencias en los pacientes no V. Conclusiones: Los pacientes con miocardio viable en el SPECT miocárdico, presentaron buen pronóstico tras revascularización y mostraron mayor riesgo de AC cuando recibieron sólo tratamiento médico. La detección de viabilidad miocárdica es una valoración indispensable en la evaluación pronóstica, y sobre todo en la toma de decisiones terapéuticas en los pacientes disfuncionales con coronariopatía multivaso (AU)

[The significance of the elevation of basal and exercise segments on Q-leads after acute myocardial infarct]. / Significado de la elevación basal y al esfuerzo del segmento ST en derivaciones con onda Q tras un infarto agudo de miocardio.

INTRODUCTION: ST segment elevation on Q-leads has been related to a greater infarct size and to the existence of ventricular aneurysm. On the other hand, ST elevation during exercise testing has been related to the presence of myocardial viability. OBJECTIVES: In the present study we investigated the relation between ST segment elevation on infarct-related electrocardiographic leads at rest and during exercise with: a) the extension and severity of the regional dysfunction; b) the presence of myocardial viability (response to dobutamine), and c) the residual stenosis in the culprit artery. MATERIAL AND METHODS: The study group was composed of 51 patients; cardiac cathetherism (8 +/- 3 days) and exercise testing (8 +/- 2 days) were performed during the pre-discharge period. In contrast ventriculography (centerline method) we determined the circumferential extension (rads) and the severity (SD/rad) of the regional dysfunction at rest and after dobutamine (10 micrograms/kg/min). The minimal luminal diameter (MLD) in the culprit artery was also measured. Results are expressed as median [Q1-Q3] and the differences among the groups were assessed by Mann-Whitney U. RESULTS: Patients with ST segment elevation in two or more leads at rest (n = 36) showed a greater (41 [30-51] rads vs 20 [14-41] rads; p = 0.007) and more severe regional dysfunction (1.9 [1.5-2.5] SD/rad vs 0.6 [0.5-2.4] SD/rad; p = 0.01), less response to dobutamine (% of reduction of the dysfunction extension after dobutamine) (17 [0-42]% vs 50 [24-100]%; p = 0.004) and smaller MLD (0.5 [0-0.9] mm vs 0.8 [0.6-1.1] mm; p = 0.03). Likewise, patients with exercise-induced ST segment elevation (n = 28) showed less response to dobutamine (15 [0-45]% vs 40 [21-57]%; p = 0.03) and smaller MLD (0.5 [0-0.7] mm vs 0.9 [0.5-1] mm; p = 0.02). There were non significant differences between patients with and without ST elevation during exercise in the extension or severity of the regional dysfunction. ST segment elevation both at rest (RR 0.2; CI 95% 0.04-0.85) and during exercise (RR 0.19; CI 95%: 0.05-0.69) decreased the probability of improvement with dobutamine. CONCLUSIONS: We conclude that ST segment elevation on Q-leads at rest is related to a more extended and severe dysfunction. Patients with ST segment elevation (at rest or during exercise) show less response to dobutamine (myocardial viability less likely) and a more severe residual coronary stenosis.