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Resumen Objetivo Analisis de la relacion coste-efectividad (RCE) del electrocardiograma de esfuerzo y de la SPECT de perfusion miocardica esfuerzo-reposo en relacion con la revascularizacion coronaria (RC), eventos cardiacos (EC) y mortalidad total (MT). Material y metodos Se estudiaron 8.496 pacientes con SPECT y seguimiento medio de 5,3 ± 3,5 anos. Evaluamos la RCE para la RC quirurgica (RCQ) y percutanea (RCP) (45,6%/54,4%) de acuerdo con los resultados de la isquemia electrocardiografica y gammagrafica. La efectividad se evaluo como MT, EC, LYSO (life-year-saved-observed) y EC-LYSO. Los analisis de costes se realizaron desde la perspectiva del pagador de atencion medica. El analisis de sensibilidad fue considerando las relaciones RCQ/RCP actuales (12%/88%). Resultados Al combinar los resultados del electrocardiograma de esfuerzo y de la gammagrafia, los valores de coste-efectividad para la RCQ variaron entre 112.589 € (isquemia electrocardiografica y gammagrafica) y 2.814.715 € (sin isquemia)/evento evitado, y entre 38.664 y 2.221.559 €/LYSO; y para la RCP entre 18.824 € (isquemia electrocardiografica y gammagrafica) y 46.377 € (sin isquemia)/evento evitado, y entre 6.464 y 36.604 €/LYSO. Para el EC: los valores de coste-efectividad de la RCQ y RCP en presencia de isquemia electrocardiografica y gammagrafica fueron de 269.904 €/EC evitado y de 24.428 €/EC evitado, respectivamente; y los €/LYSO de la RCQ y RCP fueron de 152.488 y 13.801, respectivamente. Se mantuvo la misma RCE para la proporcion actual de pacientes revascularizados (12%/88%). Conclusiones El analisis combinado de las imagenes de la SPECT y del electrocardiograma de esfuerzo permite la diferenciacion entre grupos de pacientes en donde la RCP y la RCQ son mas rentables. La mayor RCE en relacion con la RC, EC y MT se da en los pacientes con isquemia electrocardiografica y gammagrafica. La RCP es mas coste-efectiva que la RCQ.

Objective The aim was to analyze the cost-effectiveness ratio (CER) of stress electrocardiogram (ES) and stress myocardial perfusion imaging (SPECT-MPI) according to coronary revascularization (CR) therapy, cardiac events (CE) and total mortality (TM). Material and methods A total of 8496 consecutive patients who underwent SPECT-MPI were followed-up (mean 5.3 ± 3.5 years). Cost-effectiveness for coronary bypass (CABG) or percutaneous CR (PCR) (45.6%/54.4%) according to combined electrocardiographic ischemia and scintigraphic ischemia were evaluated. Effectiveness was evaluated as TM, CE, life-year saved observed (LYSO) and CE-LYSO; costs analyses were conducted from the perspective of the health care payer. A sensitivity analysis was performed considering current CABG/PCR ratios (12%/88%). Results When electrocardiogram and SPECT approaches are combined, the cost-effectiveness values for CABG ranged between 112,589 € (electrocardiographic and scintigraphic ischemia) and 2,814,715 € (without ischemia)/event avoided, 38,664 and 2,221,559 €/LYSO; for PCR ranged between 18,824 € (electrocardiographic and scintigraphic ischemia) and 46,377 € (without ischemia)/event avoided, 6464 and 36,604 €/LYSO. To CE: the cost-effectiveness values of the CABG and CPR in presence of electrocardiographic and scintigraphic ischemia were 269,904 €/CE-avoided and 24,428 €/CE-avoided, respectively; and the €/LYSO of the CABG and PCR were 152,488 and 13,801, respectively. The RCE was maintained for the current proportion of revascularized patients (12%/88%). Conclusions Combined ES and SPECT-MPI results, allows differentiation between patient groups, where the PCR and CABG are more cost-effective in different economic frameworks. The major CER in relation to CR, CE and TM occurs in patients with electrocardiographic and scintigraphic ischemia. PCR is more cost-effective than CABG.

Diabetes mellitus is an independent risk factor in the development of coronary artery disease (CAD), myocardial infarction (MI), and cardiac death (CD). The major adverse cardiac events (MACEs) between men and women in diabetic patients stratified by CAD (previous MI and/or coronary revascularization, CR) were analyzed. A cohort of 1327 consecutive diabetic patients (age 66.5 ± 9 years) underwent gated SPECT (single-photon emission computed tomography). During a mean follow-up of 4.7 ± 2.2 years post gated SPECT, MACEs (non-fatal MI, CD, and late CR) were evaluated according to gender stratified by CAD. Among diabetic patients without known CAD (N = 731), men had more MACEs (sHR 1.9;95%CI 1.2-3.2) than women. Among diabetic patients with known CAD (N = 596), there was no difference in MACEs in diabetic men and women (sHR 1.15;95%CI 0.73-1.8). Diabetic women with known CAD (n = 143) were the group with the highest risk (sHR 1.7; P = .041) for MACEs (4.5% MACEs/year, [95%CI 3.1%-6.4%]), compared to the remaining diabetic patients (N = 1184) (3% MACEs/year, [95%CI 2.6%-3.5%]). The prognosis of diabetic patients for MACEs is different in men and women stratified by CAD. The worst prognosis for MACEs occurs in women with known CAD.

AIMS To create a risk score for cardiac events (CE) according to clinical, exercise, and gated SPECT variables. METHODS AND RESULTS We analysed 5707 consecutive patients; 3181 patients (age 64.2 ± 11 years, male 59.6%) with suspected coronary artery disease (CAD) [without previous myocardial infarction (MI) or coronary revascularization (CR)] and 2526 patients (age 63.3 ± 11 years, male 81.7%) with established CAD (with previous MI or CR). To create the Vall d'Hebron Risk Score (VH-RS), first we analyse the predictors of CE (non-fatal MI, CR, and/or cardiac death), then the probability of CE for every patient according to the predictive variables. According to risk we stratified patients into four risk levels: very low risk (VLR), low risk (LR), moderate risk (MR), and high risk (HRi) using Multiple Cox Regression analysis models. Finally, we validate the VH-RS in another prospective cohort of 734 patients. In patients with suspected CAD; age (P

The effective non-invasive identification of coronary artery disease (CAD) and its proper referral for invasive treatment are still unresolved issues. We evaluated our quantification of myocardium at risk (MAR) from our second generation 3D MPI/CTA fusion framework for the detection and localization of obstructive coronary disease. Studies from 48 patients who had rest/stress MPI, CTA, and ICA were analyzed from 3 different institutions. From the CTA, a 3D biventricular surface of the myocardium with superimposed coronaries was extracted and fused to the perfusion distribution. Significant lesions were identified from CTA readings and positioned on the fused display. Three estimates of MAR were computed on the 3D LV surface on the basis of the MPI alone (MARp), the CTA alone (MARa), and the fused information (MARf). The extents of areas at risk were used to generate ROC curves using ICA anatomical findings as reference standard. Areas under the ROC curve (AUC) for CAD detection using MARf was 0.88 (CI = 0.75-0.95) and for MARp and MARa were, respectively 0.82 (CI = 0.69-0.92) and 0.75 (CI = 0.60-0.86) using the ≥70% stenosis criterion. AUCs for CAD localization (all vessels) using MARf showed significantly higher performance than either MARa or MARp or both. Using ICA as the reference standard, MAR as the quantitative parameter, and AUC to measure diagnostic performance, MPI-CTA fusion imaging provided incremental diagnostic information compared to MPI or CTA alone for the diagnosis and localization of CAD.

Reduction of left ventricular (LV) dilation (RD) beyond the first year after ST-segment-elevation myocardial infarction (STEMI) is unknown. We investigated its potential occurrence in comparison with stationary (SD) and progressive (PD) dilation.Perfusion gated SPECT features at 1 and 3 years were evaluated in 168 3-year survivors of a first anterior STEMI. Comparisons were made among patients with RD (≥15% reduction of LV end-systolic volume [LVESV]), SD (15% reduction or increase), and PD (≥15% increase). There were 35 patients with RD (21%), 84 with SD (50%), and 49 with PD (29%). At 1 year, ejection fraction, wall motion and perfusion scores, and LV volumes were similar. In RD patients, the fall in LVESV, nearly 22%, was apparent in those with frank (51 mL; P.001) or little/moderate LV dilation at 1 year (LVESV ≤51 mL; P = .002) and was associated with increased ejection fraction (P values .008 and .009, respectively). In the 3 groups, however, LVESV changes were unrelated to 1-year LV volumes, ejection fraction, or contractility score.At 3 years following anterior STEMI there is reduction of LV dilation in about 21% of patients associated with increases in ejection fraction in those with or without clearly dilated ventricles at 1year. These findings add to the complexity of LV remodeling and possibly suggest very late changes in infarct size.

Resumen Objetivos Valorar la informacion de la SPECT, de la angio-TC coronaria y de las imagenes hibridas de fusion en los pacientes con cardiopatia isquemica estable en los que se practica una coronariografia invasiva (CI). Material y metodos Se ha incluido en forma prospectiva a 46 pacientes (65,98 ± 8,3 anos) con enfermedad coronaria, valorandose la informacion de dichas tecnicas en el diagnostico de la enfermedad multivaso, en la deteccion del vaso culpable y en el manejo de los pacientes. Resultados En la CI, 29 de los 46 pacientes (63%) presentaban enfermedad multivaso: la SPECT la diagnostico en un 48,2% y la angio-TC en un 89,6%. La concordancia entre la angio-TC y la CI en el diagnostico del vaso culpable fue del 77% (kappa 0,6) y entre la SPECT y la CI del 73% (kappa 0,56). Las imagenes hibridas obtenidas despues del cateterismo no habrian aportado nueva informacion a la ya obtenida mediante la SPECT y la CI de cara al manejo terapeutico. Conclusiones La angio-TC destaca en el diagnostico de la enfermedad multivaso y en la deteccion del vaso culpable respecto a la CI. La SPECT resulta un buen complemento funcional de la CI en la deteccion del territorio mas isquemico. No obstante, en los pacientes con cardiopatia isquemica estable en los que se ha realizado una SPECT como primer estudio no invasivo, si la decision de practicar posteriormente una CI es clara, la realizacion de una angio-TC y la obtencion de imagenes de fusion SPECT-TC no parecen indicadas, ya que no cambiaria el manejo terapeutico que se adopta sobre la base de la informacion de la SPECT y la CI.

Resumen Objetivos Valorar si la estimacion del consumo maximo de oxigeno (CMO 2 ) en MET (unidad metabolica) mediante las tablas propuestas en las guias de la Sociedad Espanola de Cardiologia (SEC) es un metodo suficientemente fiable cuando se aplica a las pruebas de esfuerzo con bicicleta ergometrica. Material y metodos Se obtuvo el CMO 2 en MET por consumo de gases en bicicleta ergometrica en 97 sujetos sanos (grupo i ) y se comparo con la estimacion de los MET obtenida mediante tabla en la que solo intervienen los vatios y el peso del paciente. Mediante la introduccion de variables clinicas y ergometricas se obtuvo una formula con mejor ajuste para el calculo de los MET validandose en 289 pacientes (grupo ii ) con gated-SPECT de perfusion miocardica normal. Resultados En los individuos del grupo i se observo una buena correlacion entre los MET estimados con la tabla y los MET obtenidos mediante consumo de gases (CCI: 0,93). Sin embargo, la formula con mejor ajuste para la estimacion de los MET en los pacientes del grupo ii incluyo los vatios, el indice de masa corporal (IMC), la edad y el sexo (MET = 11,820 − 0,054 × edad − 0,189 × IMC + 1,031 × sexo + 0,020 × vatios) (mujer: 0, hombre: 1). Esta formula permitio la reclasificacion de un 46,9% de los individuos del grupo ii en la categoria Conclusiones La estimacion de los MET mediante la tabla convencional es fiable, aunque el ajuste optimo, cuando se aplica a sujetos con gated-SPECT de perfusion miocardica de esfuerzo normal, se obtiene al considerar, ademas de los vatios, el IMC, la edad y el sexo.

Resumen Paciente de 63 anos con antecedentes de implantacion de un stent en la descendente anterior 3 meses antes. Se le practico una gated-SPECT de perfusion miocardica de esfuerzo al presentar sintomas vegetativos. Durante la adquisicion de las imagenes de reposo presento dolor precordial y elevacion del segmento ST por lo que se realizo un cateterismo cardiaco urgente que evidencio una trombosis aguda intra-stent. Las imagenes de perfusion correspondientes al reposo demostraron un defecto de perfusion anterior y apical, mas intenso y extenso que en las imagenes de esfuerzo, con una llamativa dilatacion ventricular izquierda y caida de la fraccion de eyeccion, en relacion con el fenomeno de isquemia aguda. El ejercicio intenso se asocia con una activacion transitoria del sistema de coagulacion y cambios hemodinamicos que pueden inducir trombosis, especialmente en stents coronarios recientemente implantados y probablemente no completamente endotelizados.

A 63-year-old male patient with a history of stent implantation in the left anterior descending three months before. Due to the presentation of vegetative symptoms, he was referred for gated-SPECT myocardial perfusion. During acquisition of the resting images he presented chest pain and ST segment elevation, so that urgent cardiac catheterization was performed, showing stent thrombosis. Rest perfusion imaging showed a defect in anterior and apical perfusion, more severe and extensive than in the stress images, with striking left ventricular dilatation and a fall in the ejection fraction related to the acute ischemia phenomenon. Intense exercise is associated with a transient activation of the coagulation system and hemodynamic changes that might induce thrombosis, especially in recently implanted coronary stents that probably still have not become completely endothelialized.

To assess different warranty periods following a normal myocardial perfusion SPECT based on patients' clinical characteristics and the type of stress performed.A study was done of 2,922 consecutive patients (62.9 ± 13 years; 53.4% women) with a normal stress-rest SPECT. The warranty period was defined as the period during which patients remained at a low risk (1% events/year) of total mortality (TM), or hard events (HE) (cardiac death or non-fatal myocardial infarction). Of these patients, 2,051 were given an exercise myocardial perfusion imaging (Ex-MPI); 461 submaximal exercise plus dipyridamole (Ex+Dipy-MPI); and 410 dipyridamole (Dipy-MPI). During a mean follow-up of 5 ± 3.3 years, a significant reduction (P.05) of the warranty period for TM (13.5, 9.6 and 8 months) and HE (34.8, 20.5 and 8.2 months) was observed, for Ex-MPI, Ex+Dipy-MPI and Dipy-MPI, respectively. Other warranty period determinants were the clinical variables of age, sex, diabetes and known coronary artery disease. An abnormal left ventricular ejection fraction on gated-SPECT also significantly shortened the warranty period for HE in patients undergoing Ex+Dipy-MPI (P = .001) or Dipy-MPI alone (P = .007).The warranty period for a normal stress-rest SPECT is highly variable since it is primarily determined by the type of stress, the patient's clinical characteristics and LVEF.

Resumen Objetivo El objetivo de este estudio fue investigar que variables en el momento de la practica de una gated-SPECT de perfusion miocardica normal son predictoras de la indicacion de una segunda gated-SPECT. Material y metodos Estudio unicentrico, prospectivo de cohorte. Se incluyeron consecutivamente 2.326 pacientes (edad 63,6 ± 13 anos, 57,3% mujeres) sin defectos de perfusion y con una fraccion de eyeccion del ventriculo izquierdo normal en una gated-SPECT de perfusion miocardica estres-reposo. Se estudiaron variables clinicas y ergometricas predictoras de la indicacion de una nueva gated-SPECT y de la presencia de defectos reversibles de perfusion en esta ultima. Resultados Durante un seguimiento medio de 3,6 ± 2 anos despues de una gated-SPECT normal se practico una segunda gated-SPECT en 286 pacientes (12,3%). Las variables predictoras independientes que influyeron en la indicacion de una segunda gated-SPECT fueron la presencia de 3 o mas factores de riesgo cardiovascular (χ2: 5.501; HR: 1,4; p = 0,019), el antecedente de infarto agudo de miocardio (χ2: 3.862; HR: 1,4; p = 0,049), la revascularizacion coronaria previa (χ2: 41.063; HR: 2,5; p 2 : 4.322; HR: 1,9; p = 0,038) que realizaron una primera gated-SPECT farmacologica pura (χ 2 : 7.182; HR: 2,6; p = 0,007). Conclusiones En los pacientes con una gated-SPECT de perfusion miocardica normal diversos factores clinicos y variables derivadas de la prueba de estres influyen en la indicacion de una segunda gated-SPECT y en la presencia de isquemia en esta ultima.

The objective of this study was to investigate predictor variables at the moment of normal stress-rest myocardial perfusion gated SPECT for indication of a second gated SPECT.A prospective, single center cohort study was conducted. We evaluated 2326 consecutive patients (age 63.6 ± 13 years, 57.3% females) without perfusion defects and with normal left ventricular ejection fraction on a myocardial perfusion gated SPECT. Clinical and stress test variables were studied to predict indication of a second gated SPECT and presence of reversible perfusion defects in the second gated SPECT.During a mean follow-up of 3.6 ± 2 years a second gated SPECT was performed in 286 patients (12.3%). Independent predictor variables of a second gated SPECT were presence of three or more cardiovascular risk factors (χ(2): 5.510; HR: 1.4; p=0.019), previous acute myocardial infarction (χ(2): 3.867; HR: 1.4; p=0.049), previous coronary revascularization (χ(2): 41.081; HR: 2.5; p0.001), and a positive stress test (χ(2): 8.713; HR: 1.5; p=0.003). Observation of perfusion defects in the 280 patients in whom a second stress-rest gated SPECT was performed was more likely in male patients (χ(2): 4.322; HR: 1.9; p=0.038) who had a first pure pharmacological gated-SPECT (χ(2): 7.182; HR: 2.6; p=0.007).In patients with a first normal myocardial perfusion gated SPECT, various clinical factors and variables derived from the stress test affect the indication of a second gated SPECT and the presence of ischemia in the latter.

Resumen La imagen cardiaca es la piedra angular del diagnostico en cardiologia, asi como un instrumento esencial en la valoracion pronostica y las decisiones terapeuticas. Este ano, la ecocardiografia destaca como guia en el intervencionismo y en la eleccion del tamano de las protesis. Se consolida la entidad de la estenosis aortica de bajo flujo y bajo gradiente. El metodo tridimensional avanza en el conocimiento anatomico y la cuantificacion valvular. Los parametros de deformacion muestran su poder predictor en valvulopatias y en el seguimiento en la cardiotoxicidad inducida por farmacos. La tomografia computarizada por emision monofotonica y la tomografia por emision positronica consolidan su utilidad en cardiopatia isquemica y destacan en el diagnostico de inflamaciones e infecciones cardiacas. La tomografia computarizada cardiaca afianza su papel en la coronariografia no invasiva, el manejo del dolor toracico en urgencias, la valoracion de las oclusiones cronicas y el estudio morfologico de la placa. La resonancia magnetica cardiaca permanece como tecnica de referencia en la caracterizacion tisular tanto en cardiopatia isquemica como en las miocardiopatias y afianza su papel en el estudio de estres y la valoracion de la viabilidad.

Resumen Introduccion y objetivos El objetivo de este estudio es comparar los resultados de la resonancia magnetica y la gated- SPECT de perfusion miocardica en la valoracion de la funcion ventricular y la viabilidad en pacientes con infarto de miocardio en fase cronica. Metodos Se estudio con resonancia magnetica y gated- SPECT a 104 pacientes (media de edad, 61 ± 12 anos; el 87,5% varones) con infarto previo. Se correlacionaron los volumenes y la fraccion de eyeccion del ventriculo izquierdo y los criterios clasicos de viabilidad con realce tardio con gadolino ( 50%) en los 17 segmentos del ventriculo izquierdo. Se valoro la motilidad, el engrosamiento y la isquemia en la gated- SPECT de los segmentos no viables o con criterios dudosos con el realce (un 50-75% de transmuralidad). Resultados Se observo buena correlacion entre ambas exploraciones para los volumenes y la fraccion de eyeccion (p 75%, 82 (31%) tenian captacion > 50% en la SPECT. De los 106 segmentos con criterios dudosos de viabilidad (un 50-75% de realce) en la resonancia magnetica, en la SPECT 68 (64%) tenian una captacion > 50%; 41 (38,7%), motilidad conservada; 46 (43,4%), engrosamiento conservado, y 17 (16%), criterios de isquemia. Conclusiones Una tercera parte de los segmentos considerados no viables en la resonancia magnetica muestran captacion > 50% en la SPECT. El analisis de la motilidad, engrosamiento y presencia de isquemia en la gated- SPECT es de utilidad en los segmentos de dudosa viabilidad en la resonancia magnetica.

The arterial switch operation (ASO) is the preferred technique for correcting transposition of the great arteries, but translocation and reimplantation of the coronary arteries can produce myocardial ischemia. This report aims to describe the authors' experience with exercise single-photon emission computed tomography (SPECT) used to evaluate myocardial perfusion. Exercise-rest gated-myocardial perfusion SPECT was performed for 69 patients (49 boys; median age, 9 years; 5th percentile [6.4 years] to 95th percentile [15.6 years]), 64 of whom were asymptomatic 9.98 ± 3.20 years after ASO. During exercise testing, the patients reached 9.85 ± 3.05 metabolic equivalents (METs) and a median heart rate of 160 beats per minute (bpm), 5th percentile (106 bpm) to 95th percentile (196 bpm). Whereas 61 patients (88.41 %) had normal myocardial perfusion, 2 patients (2.9 %) had reversible defects, and 6 patients (8.7 %) had fixed defects. All the patients with perioperative ischemic complications (4/4, 100 %) had myocardial perfusion defects, whereas four patients (4/65, 6.15 %) without ischemic complications had abnormal perfusion (p = 0.0005). Age at the time of surgery did not differ significantly (p = 0.234) between the patients with perfusion defects and those with normal study results. No significant difference was observed between the patients who had an A coronary pattern (left coronary artery originating from the left sinus and the right coronary artery originating from the right sinus, n = 47) and those who had a non-A coronary pattern (n = 22) (p = 1). The high rate for normality of exercise myocardial perfusion in our study suggests that myocardial perfusion gated-SPECT should be reserved for patients who have experienced perioperative ischemic complications or those with symptoms, at least during the first 10 years after the surgery.

Background— The incremental prognostic value of myocardial perfusion–gated single photon emission computed tomography (MPGS) compared with exercise test has not yet been properly evaluated. Methods and Results— Five thousand six hundred seventy-two consecutive patients with known or suspected coronary disease undergoing exercise MPGS between 1997 and 2007 were included. Three-year predictive models for total death and death from cardiovascular causes or acute myocardial infarction (ie, major cardiovascular events [MCE]) were built using Cox-regression modeling, including only the clinical information. Then the exercise and MPGS information was sequentially added. The added discriminative ability of exercise test information and MPGS was assessed by net reclassification improvement and integrated discrimination improvement. The increase in predictive ability of exercise information for death and MCE was high as assessed by net reclassification improvement (0.199 and 0.263) and integrated discrimination improvement (0.042 and 0.021). The only variable of MPGS associated with total death was ejection fraction (hazard ratio, 0.84; 95% confidence interval, 0.79–0.89; P P =0.007). Adding MPGS information barely improved the prognostic value for total death (net reclassification improvement, 0.017; integrated discrimination improvement, 0.013), but it increased for MCE (net reclassification improvement, 0.122; integrated discrimination improvement, 0.033). Conclusions— Adding MPGS information to exercise information does not improve prediction of total death, although it allows a more accurate prediction of MCE.

Resumen Introduccion y objetivos La distension de la region isquemica se ha relacionado con una mayor incidencia de arritmias ventriculares espontaneas tras la oclusion coronaria. Analizamos si la distension isquemica regional predice una mayor inducibilidad de fibrilacion ventricular tras la oclusion coronaria en cerdos. Metodos En 18 cerdos anestesiados con torax abierto, se ocluyo la descendente anterior durante 60 min. Se monitorizo la longitud segmentaria en la region isquemica mediante cristales ultrasonicos. Se realizo estimulacion programada basal, y despues continuamente entre 10 y 60 min tras la oclusion. Resultados La oclusion coronaria indujo un rapido aumento en la longitud telediastolica en la region isquemica, que alcanzo el 109,4 ± 0,9% de los valores basales a los 10 min (p Conclusiones La distension regional isquemica predice una mayor inducibilidad de fibrilacion ventricular tras la oclusion coronaria. Estos resultados subrayan la influencia potencial de los factores mecanicos, que actuan no solo sobre los desencadenantes, sino tambien sobre el sustrato, en la genesis de las arritmias ventriculares malignas durante la isquemia aguda.

Distension of the ischemic region has been related to an increased incidence of spontaneous ventricular arrhythmias following coronary occlusion. This study analyzed whether regional ischemic distension predicts increased ventricular fibrillation inducibility after coronary occlusion in swine.In 18 anesthetized, open-chest pigs, the left anterior descending coronary artery was ligated for 60 min. Myocardial segment length in the ischemic region was monitored by means of ultrasonic crystals. Programmed stimulation was applied at baseline and then continuously between 10 and 60 min after coronary occlusion.Coronary occlusion induced a rapid increase in end-diastolic length in the ischemic region, which reached 109.4% (0.9%) of baseline values 10 min after occlusion (P.001). On average, 6.6 (0.5) stimulation protocols were completed and 5.4 (0.6) ventricular fibrillation episodes induced between 10 and 60 min of coronary occlusion. Neither baseline serum potassium levels nor the size of the ischemic region were significantly related to ventricular fibrillation inducibility. In contrast, the increase in end-diastolic length 10 min after coronary occlusion was associated directly (r=0.67; P=.002) with the number of induced ventricular fibrillation episodes and inversely (r=-0.55; P=.018) with the number of extrastimuli needed for ventricular fibrillation induction.Regional ischemic expansion predicts increased ventricular fibrillation inducibility following coronary occlusion. These results highlight the potential influence of mechanical factors, acting not only on the triggers but also on the substrate, in the genesis of malignant ventricular arrhythmias during acute ischemia.

OBJECTIVE Noninvasive differentiation between ischemic cardiomyopathy (ICM) and nonischemic (NICM) cardiomyopathy is frequently difficult. The aim of this study was to analyze the value of stress test and stress-rest gated single-photon emission computed tomography (SPECT) criteria to differentiate between ICM and NICM. METHODS Data pertaining to 145 consecutive patients (mean age: 63±11 years, 24 women) assessed by means of stress-rest gated SPECT with Tc-tetrofosmin, with left ventricular ejection fraction less than or equal to 40% (107 patients with ICM and 38 with NICM according to coronary angiography) and known coronary anatomy, were analyzed. RESULTS Multivariate analyses of gated SPECT variables identified a summed stress score greater than 21 [odds ratio (OR) 7.67, 95% confidence interval (CI): 2.85-20.58)] and divergent pattern (OR 6.84, 95% CI: 1.83-25.5) as predictors of ICM, and analysis of exercise test variables disclosed metabolic equivalents less than or equal to 7.3 (OR 10.75, 95% CI: 3.64-31.81) and ST depression of at least 1 mm (OR 6.97, 95% CI: 1.42-34.3) as independent predictors of ICM. The exercise test variables had a significant additional predictive value of ICM over gated SPECT variables (P

Objective To evaluate the evolutive changes in diastolic function after percutaneous coronary revascularization (PCR) in acute myocardial infarction (AMI), using myocardial perfusion gated SPECT. Methods Thirty-two patients (mean 61.9 ± 9.7 years, 7 women) were studied by two at rest gated SPECT: the first gated-SPECT-1 was performed with an injection of a dose of 99mTc-tetrofosmin prior to PCR and the second gated-SPECT-2 between the fourth and fifth weeks after AMI. Changes of peak filling rate (PFR) and the time to peak filling rate (TTPF) were assessed between both studies, and were related to the extent of salvaged myocardium (SM), end-diastolic (EDV) and end-systolic (ESV) volumes, and left ventricular ejection fraction (LVEF) changes. Results An improvement was observed in diastolic function parameters gated-SPECT-2: PFR increased significantly (p = 0.011) while the TTPF decreased without reaching statistical significance (p = 0.288). In multivariate analysis, adjusted by clinical and coronary variables, improvement of PFR was significantly associated with percentage of SM (p = 0.030), increase in LVEF (p = 0.004) and with ESV volume reduction (p = 0.005). Improvement of TTPF was only related significantly to the percentage of SM (p = 0.046). PFR increased by 0.01 EDV/s. and TTPF decreased by 1.14 ms for each cm2 increase of the area of SM. Conclusions After PCR in AMI, the myocardial perfusion gated SPECT makes it possible to assess the significant improvement in diastolic function mainly related to the amount of MS.

Resumen Objetivo Valorar mediante gated-SPECT de perfusion miocardica los cambios evolutivos de la funcion diastolica despues de la revascularizacion coronaria percutanea (RCP) de un infarto agudo de miocardio (IAM). Material y metodos Se estudiaron consecutivamente 32 pacientes (media 61,9 ± 9,7 anos; 7 mujeres) mediante 2 gated-SPECT de perfusion miocardica en reposo: la primera gated-SPECT-1 con inyeccion de una dosis de 99mTc-tetrofosmina previa a la RCP y la segunda gated-SPECT-2 entre la cuarta y quinta semana despues del IAM. Se valoraron los cambios de la velocidad maxima de llenado (Vmax) y del tiempo a la velocidad maxima de llenado (TVmax) entre ambos estudios, relacionandolos con la extension del miocardio salvado (MS) y con los cambios observados en los volumenes telediastolico (VTD) y telesistolico (VTS) y en la fraccion de eyeccion del ventriculo izquierdo (FEVI). Resultados En la gated-SPECT-2 se observo una mejoria de los parametros de la funcion diastolica: la Vmax aumento significativamente (p = 0,011) mientras que el TVmax disminuyo sin alcanzar significacion estadistica (p = 0,288). En el analisis multivariante, ajustado por variables clinicas y coronariograficas, el aumento de la Vmax se relaciono significativamente con el porcentaje de MS (p = 0,030), el aumento de la FEVI (p = 0,004) y la reduccion del VTS (p = 0,005). La mejoria del TVmax solo se relaciono significativamente con el porcentaje de MS (p = 0,046). Por cada cm2 de aumento del area del MS la Vmax aumento 0,01 VTD/s y la TVmax disminuyo 1,14 ms. Conclusiones Tras la RCP en el IAM, la gated-SPECT de perfusion miocardica permite valorar la mejoria significativa de la funcion diastolica que se relaciona fundamentalmente con la cantidad de MS.

The aim of this study was to establish different degrees of mechanical dyssynchrony according to validated cut-off (CO) values of myocardial perfusion gated SPECT phase analysis parameters (SD, standard deviation; B, bandwidth; S, skewness; K, kurtosis). Using Emory Cardiac Toolbox™, we prospectively analyzed 408 patients (mean age 64.1 years, 26.7% female), divided into a control group of 150 normal subjects and a validation group of 258 patients (left bundle branch block: 17.8%, right bundle branch block: 8.9%. atrial fibrillation: 16.3%, coronary revascularization: 30%, dilated cardiomyopathy: 7.4%. valvulopathies: 2.7%, ischemic test: 45.3%) with ischemic and non-ischemic cardiac diseases, by means of phase analysis. Agreement of CO values (SD > 18.4°; B > 51°; S ≤ 3.2; K ≤ 9.3) used to discriminate between normal subjects and patients was strong (c-statistic 0.9; 95% CI 0.98-0.99). Four degrees of dyssynchrony were found according to the number of abnormal phase parameters. All patients with mechanical and electrical criteria for cardiac resynchronization therapy (CCRT) (n: 82) had Grade 2 to 4 (two to four abnormal phase parameters). Agreement of CO values (SD > 40.2°; B > 132°; S ≤ 2.3; K ≤ 4.6) used to discriminate between patients with and without CCRT was strong (c-statistic 0.8; 95% CI 0.79-0.87) but 12% of patients with CCRT did not have any of these abnormal phase parameters. The discriminatory capacity of gated SPECT phase analysis parameters between normal subjects and patients, and between patients with and without CCRT, is very good, making it possible to define different degrees of mechanical dyssynchrony.

Background To analyse prognosis according to different clinical, electrocardiographic and scintigraphic responses on stress myocardial perfusion scintigraphy. Methods 3579 consecutive patients (age 63.1±12; women: 46.8%) without known coronary artery disease were evaluated with a stress-rest myocardial perfusion single photon emission computed tomography (SPECT). In accordance with clinical (chest pain: ChP), electrocardiographic (ST+) and scintigraphic (SPECT+) ischemia criteria, patients were divided into 5 groups: Group 1 (n=1902; with normal exercise test and SPECT without ChP); Group 2 (n=456): ChP−, ST+ and SPECT−; Group 3 (n=594): ChP− and SPECT+; Group 4 (n=444): ChP+ and SPECT−; and Group 5 (n=183): ChP+ and SPECT+. Results During a follow-up of 5.1±3.4years, cardiac events (CE: cardiac mortality or nonfatal myocardial infarction) were significantly higher in groups 2 to 5 than in group 1 (p Conclusions SMI has incremental prognostic value over clinical variables and symptomatic ischemia. In the context of SMI, a similar prognosis was observed between patients with only ST+ and patients with only SPECT+, but significant worse prognosis was observed in patients with ST+ plus SPECT+.

Purpose Ischemic cardiomyopathy (ICM) is a disease with high morbidity and mortality. There are several published studies on the evolution and prognosis of patients with ICM. However, reports on the therapeutic management in clinical practice are scarce. The aim of this study was to analyze coronary revascularization (CR) performance in patients with ICM and suitable coronary anatomy according to myocardial perfusion stress-rest gated SPECT results. Patients and methods Eighty-seven consecutive patients (mean age, 62.4 y; 20 women), with ischemic heart disease, left ventricular ejection fraction of 40% or less, coronary anatomy suitable for CR, and without previous CR, were evaluated by means of stress-rest gated SPECT. Results Sixty-four percent of patients had scintigraphic criteria of viability and 62.1% showed scintigraphic ischemia in stress-rest gated SPECT. Forty-five percent of patients were revascularized, and the remainder received medical treatment only. Coronary revascularization was more frequent in patients with scintigraphic viability (P = 0.012), in those with scintigraphic ischemia (P = 0.007), and in those with low left ventricular end-systolic volume (P = 0.006). Cox regression analysis identified multivessel disease [hazard ratio (HR), 3.3; 95% confidence interval (CI), 4-7.8], summed difference score greater than 4 (HR, 3.9; 95% CI, 1.5-9.8), and left ventricular end-systolic volume less than 120 mL (HR, 3.2; 95% CI, 1.3-8.2) as the best independent predictors of CR treatment. Conclusions In patients with ICM and suitable coronary arteries who are able to perform a stress myocardial perfusion-gated SPECT, the presence of multivessel disease and myocardial ischemia and the absence of severely increased left ventricular volume were associated to a decision of CR.

Objectives To assess the significance of a paradoxical pattern (PP) (greater tracer uptake during stress than at rest) on gated myocardial perfusion SPECT in myocardial regions with myocardial necrosis.

Cardiac imaging continues to reveal new anatomical and functional insights into heart disease. In echocardiography, both transesophageal and transthoracic three-dimensional imaging have been fully developed and optimized, and the value of the techniques that have increased our understanding of cardiac mechanics and ventricular function is well established. At the same time, the healthcare industry has released new devices onto the market which, although they are easier to use, have limitations that restrict their use for routine assessment. Tomography's diagnostic and prognostic value in coronary artery disease continues to increase while radiation exposure becomes progressively lower. With cardiac magnetic resonance imaging, myocardial injury and recovery in ischemic heart disease and following acute coronary syndrome can be monitored in exquisite detail. The emergence of new combined tomographic and gamma camera techniques, exclusively developed for nuclear cardiology, have improved the quality of investigations and reduced radiation exposure. The hybrid or fusion images produced by combining different techniques, such as nuclear cardiology techniques and tomography, promise an exciting future.

Objectives In patients with depressed systolic function after recent acute myocardial infarction (AMI), improvement of global left ventricular (LV) systolic function using low-dose dobutamine (LDD) may be influenced by factors different from those observed in patients with chronic ischemic cardiomyopathy (CIC). The aim of this study was to analyze, by means of myocardial perfusion-gated single photon emission computed tomography, segmental thickening (STh), LV volumes and ejection fraction (EF), at baseline and during LDD infusion in patients with systolic dysfunction early after AMI, and compare these results with those in patients with CIC. Methods Prospective, multicenter study. Eighty-nine patients {mean 60.7 years [standard deviation (SD)=12.9]} with coronary artery disease and LVEF less than or equal to 40% were investigated with resting gated single photon emission computed tomography with LDD, 41 patients between 5 and 8 days post-AMI, and 48 patients with CIC. Results Post-AMI the patients had lower LVEF, worse STh scores, and a greater number of segments with severely diminished thickening than patients with CIC. In post-AMI patients, contractile reserve in segments with severely impaired baseline thickening was predictive of a more than or equal to 5% increase in LVEF [odds ratio (OR): 3.77], whereas in patients with CIC the predictors were global contractile reserve (OR: 2.45) and a lower resting end-diastolic volume (OR: 0.98). Conclusion Improvement of LVEF with LDD in patients with systolic dysfunction early after AMI depended essentially on contractile reserve in segments with severely impaired baseline thickening, whereas in patients with CIC it depended on overall LV contractile reserve and the presence of less ventricular remodeling.

Resumen Objetivo El objetivo de este estudio fue analizar como la gated-SPECT (Single Photon Emission Computed Tomography) de perfusion miocardica influye en la practica de una coronariografia en los pacientes con miocardiopatia isquemica (MI). Material y metodos Se evaluaron consecutivamente 120 pacientes (edad media: 64,9 ± 11,5 anos, 25 mujeres) con MI (fraccion de eyeccion ventricular izquierda ≤ 40%) mediante gated-SPECT de perfusion miocardica (96 estres-reposo y 24 solo reposo) y sin coronariografia previa. La fraccion de eyeccion (FE) fue obtenida en reposo mediante gated-SPECT. El origen isquemico de la disfuncion sistolica se establecio mediante coronariografia en los 64 pacientes en que fue practicada despues de la gammagrafia y por el antecedente de infarto de miocardio en el resto. Los resultados de la gated-SPECT se compararon con los de los 56 pacientes en los que no se indico la coronariografia. Resultados La isquemia miocardica gammagrafica (HR: 5,2; IC 95%: 2,68 a 10,35) en los pacientes que habian podido realizar una prueba de estres y la disminucion severa de la fraccion de eyeccion (FE Conclusiones En los pacientes con MI, la demostracion de isquemia y la reduccion severa de la FE en la gated-SPECT de perfusion miocardica influyeron en la indicacion de una coronariografia, sin que los criterios gammagraficos de viabilidad tuvieran un impacto significativo en esta decision.

Introduccion y objetivos El objetivo de este estudio es evaluar la eficacia diagnostica de la tomografia computarizada por emision monofotonica (SPECT) de perfusion miocardica con la administracion de atropina intravenosa al final de una prueba de esfuerzo con insuficiente taquicardizacion. Metodos A 172 pacientes que, a pesar de realizar una prueba ergometrica limitada por sintomas, no alcanzaron un 80% de taquicardizacion, sin presentar angina ni descenso del segmento ST ≥ 1 mm, se les administro 1 mg de atropina intravenosa al final del esfuerzo. A 23 de estos pacientes con criterios de isquemia gammagrafica en la SPECT con atropina, y en el curso de 1 semana, se les practico una segunda SPECT sin la administracion de atropina con la finalidad de comparar la presencia y la gravedad de la isquemia gammagrafica entre los dos estudios (suma puntuacion diferencial [SPD]). Resultados De los 172 pacientes, 75 (43,6%) presentaron angina (n = 56) o descenso del segmento ST (n = 30) con la administracion de atropina. De los 23 pacientes en los que se hicieron ambas pruebas, 8 (35%) tuvieron isquemia (SPD ≥ 2) unicamente en la prueba con atropina. Ademas, la SPD fue significativamente superior en las imagenes de SPECT con atropina (5,6 ± 4,5 frente a 3,1 ± 2,8; p = 0,0001). Conclusiones La administracion de atropina al final de una prueba de esfuerzo insuficiente permite obtener criterios gammagraficos de isquemia en una tercera parte de los casos en que no se habria obtenido sin la administracion del farmaco.

Resumen Introduccion y objetivos El objetivo de este estudio ha sido crear una base de datos espanola (BDE) de normalidad de la SPECT (single photon emission computed tomography) de perfusion miocardica y compararla con una base de datos de normalidad de poblacion norteamericana. Metodos Se selecciono a 104 voluntarios sanos (45 mujeres, media de edad, 42 ± 14 anos) a los que se practico una SPECT de estres y reposo, procesandose los estudios en el programa comercial 4DM-SPECT. La BDE de normalidad generada para varones y mujeres se comparo con la base de datos de la poblacion norteamericana (70 varones y 60 mujeres) que proporciona el programa 4DM-SPECT. Resultados En la BDE el mayor porcentaje de captacion correspondio a la region lateral-medial, y el menor, a la region septal-basal, tanto en estres como en reposo. En las mujeres el porcentaje de captacion de la region anterior-medial fue significativamente mas bajo que en los varones, mientras que en estos se observo una menor captacion en las regiones inferiores, septal medial y apical con respecto a las mujeres. Los valores de la BDE fueron significativamente mas bajos que los de la 4DMSPECT en la mayoria de las regiones. Conclusiones Se ha creado una base de datos de normalidad espanola para mujeres y varones por separado de la SPECT de perfusion miocardica, y se ha observado que hay diferencias significativas con una base de datos comercial de origen norteamericano que suele utilizarse en estudios semicuantitativos.

Resumen Objetivo Analizar la funcion sistolica ventricular izquierda y la perfusion miocardica entre los protocolos corto esfuerzo reposo en un solo dia y largo en 2 dias de la gated-SPECT (Single Photon Emision Computed Tomography) de perfusion miocardica en pacientes con miocardiopatia isquemica. Metodos Estudio prospectivo de 40 pacientes (59,6±8,9 anos, 3 mujeres) con miocardiopatia isquemica (fraccion de eyeccion (FE) ventricular izquierda ≤40%) estudiados mediante gated-SPECT. Entre 5–10 dias despues de realizar el protocolo corto esfuerzo reposo (gated-SPECT-1) los pacientes fueron recitados para un segundo estudio de reposo (gated-SPECT-2) para comparar los resultados de la FE y de las diferencias de la suma de puntuacion de perfusion en reposo (ΔSPR=SPR1–SPR2) y de la suma de puntuacion de perfusion diferencial (ΔSPD=SPD1–SPD2) entre ambos protocolos. Resultados En 26 pacientes (65%) la FE de la gated-SPECT-2 fue superior (37 vs 34%, p=0,008) a la de la gated-SPECT-1 y en 11 pacientes (27,5%) el incremento fue ≥5%. No hubo diferencias clinicas ni coronariograficas significativas entre los pacientes con y sin aumento de la fraccion de eyeccion ≥5%. En el analisis multivariante ΔSPR (IC95%: −1,1 a −29,2) y ΔSPD (0,179–1,236) fueron predictoras del incremento de la FE ≥5% entre ambos estudios. Conclusiones En los pacientes con miocardiopatia isquemica la practica de un protocolo corto esfuerzo reposo puede infravalorar la FE del ventriculo izquierdo. El aturdimiento miocardico postestres y la posible contaminacion de las imagenes de reposo con las del esfuerzo previo en el protocolo corto permitirian explicar en parte estos resultados.

Introduccion y objetivos. Analizar la respuesta contractil negativa (RCN) del ventriculo izquierdo (VI) en la gated-SPECT con bajas dosis de dobutamina (BDD) en pacientes con miocardiopatia isquemica (MI). Metodos. Se estudio prospectivamente a 68 pacientes (media de edad, 60 ± 11 anos; 7 mujeres) con MI mediante gated-SPECT en reposo y durante la infusion de BDD. Se relaciono la RCN (aumento de la puntuacion del engrosamiento = 1 unidad) con los criterios gammagraficos de viabilidad y los resultados de la coronariografia. Resultados. El 42,6% (29/68) de los pacientes presento uno o mas segmentos con RCN. En el 14,7% (n = 10) de los pacientes se observo una disminucion de la fraccion de eyeccion = 4% con las BDD. Estos pacientes se caracterizaron por tener un mayor numero de segmentos con RCN (2,8 ± 2,5 frente a 0,87 ± 0,4; p = 0,042), con un valor de corte en el analisis de curva ROC = 2 segmentos con RCN (sensibilidad, 70%; especificidad, 74%; +LR, 2,71; -LR, 0,40). El 94% (74/79) de los segmentos con RCN correspondia a miocardio vivo (normal o viable gammagraficamente). De los 17 segmentos con acinesia o hipocinesia severa y RCN, 12 (71%) tenian criterios gammagraficos de viabilidad y en su mayoria (10/12) correspondian a territorios con arteria coronaria abierta. Conclusiones. La RCN no es un fenomeno infrecuente en los pacientes con MI y se relaciona con una disminucion de la funcion sistolica general del VI. Mayoritariamente se observa en segmentos con criterios gammagraficos de viabilidad y dependientes de una arteria coronaria abierta

The aim of this study was to assess interassay reproducibility of myocardial perfusion gated-SPECT for calculation of end-diastolic volume (EDV), end-systolic volume (ESV), and left ventricular ejection fraction (LVEF) in patients with atrial fibrillation (AF).One hundred and fifteen consecutive patients with AF from three participating hospitals (mean age 68.9 years, 39 women) were included in the study. All patients underwent two image gated acquisitions at rest with a 30 minute interval between them. Quantitative data were obtained using the QGS and ECT software algorithms.Heart rate was similar in both studies: 74.94 +/- 15.2 vs 73.03 +/- 15.57. QGS yielded an LVEF of 54.4%/53.8%, an EDV of 100 mL/101.5 mL, and an ESV of 51 mL/52.3 mL; and ECT showed an LVEF of 63.6%/62.9%, an EDV of 125.8 mL/127.4 mL and ESV of 54.1 mL/56.3 mL. Correlation between the two acquisitions was high (0.948) for both methods for LVEF, EDV and ESV. Regression and Bland-Altman graphics showed a good agreement between all parameters. Interassay variation coefficients for each method (QGS/ECT) were 5.29% vs 4.83% for LVEF, 4.94% vs 5.17% for EDV, and 9.94% vs 12.78% for ESV.Interassay reproducibility of LVEF and EDV with gated-SPECT in patients with AF is good, whereas for ESV it is suboptimal, particularly when ESV is small.

La miocardiopatia isquemica es consecuencia de una enfermedad coronaria severa y extensa que conlleva una disfuncion del ventriculo izquierdo y, en muchas ocasiones, una importante dilatacion de este. Su mortalidad es elevada, sobre todo en los pacientes con criterios de viabilidad miocardica que no son revascularizados. Si bien la edad, la capacidad de ejercicio y las comorbilidades influyen en la supervivencia, la isquemia, la viabilidad miocardica y el remodelado ventricular son variables pronosticas importantes y todas ellas pueden valorarse adecuadamente mediante la gated-SPECT de perfusion miocardica.

La utilizacion de la fraccion de eyeccion del ventriculo izquierdo como objetivo subrogado en los ensayos clinicos esta avalada por numerosos estudios. Para que el rendimiento de este objetivo sea aceptable, es esencial ser muy rigurosos en la adquisicion de las imagenes y es conveniente utilizar unidades especificamente dedicadas a analizar cuantitativamente parametros de imagen con las diversas tecnicas disponibles. A continuacion se expone la evidencia disponible en relacion con la fraccion de eyeccion y los volumenes del ventriculo izquierdo, la importancia de las unidades de analisis de imagen y las distintas tecnicas disponibles. Finalmente, se comenta sobre las tecnicas de imagen de eleccion segun el contexto clinico.

Resumen Objetivos Evaluar el numero de sujetos que es necesario tratar (NNT) mediante revascularizacion coronaria (RC) para obtener 1 supervivencia, en relacion con la presencia o ausencia de viabilidad miocardica en las imagenes de la gated-SPECT (tomografia computarizada por emision de foton unico, del ingles single photon emission computed tomography ) de perfusion miocardica, de pacientes con miocardiopatia de origen isquemico (MOI). Metodo Se estudiaron consecutivamente 198 pacientes con MOI mediante gated -SPECT de reposo con compuestos tecneciados. Se analizo la mortalidad cardiaca en 4 grupos: viables con RC (n = 50); no viables con tratamiento medico (TM) (n = 90); no viables con RC (n = 18), y no viables con TM (n = 40). Resultados Durante un seguimiento medio de 2,3 anos la mortalidad cardiaca en los pacientes con criterios gammagraficos de viabilidad miocardica revascularizados fue de 5,9/100 pacientes/ano y en los que continuaron con TM 12,9/100 pacientes/ano. En los pacientes sin criterios de viabilidad revascularizados la mortalidad cardiaca fue de 6,2/100 pacientes/ano y en los que recibieron TM 1,9/100 pacientes/ano. En los pacientes con criterios de viabilidad el NNT fue de 4 y en los pacientes sin viabilidad miocardica fue de 24. Conclusiones El NNT mediante RC para obtener 1 supervivencia en los pacientes con criterios gammagraficos de viabilidad fue 6 veces menor con respecto a los pacientes sin criterios de viabilidad, con un menor coste y mortalidad.

There are no extensive series in which risk stratification of patients with ischemic cardiomyopathy (IC) is based on their rest and exercise and scintigraphic characteristics. The purpose of our study was to analyze rest and exercise myocardial perfusion-gated SPECT variables for prognosis in patients with ischemic IC.Prospective cohort study. A study was performed in 167 patients with IC who consecutively underwent rest myocardial perfusion-gated SPECT. In addition, stress SPECT was performed on 137 of these patients. During an average follow-up of 2.3 +/- 1.2 years, cardiac mortality (CM) was 17.4%. Independent predictors of CM in rest-gated SPECT were the positive criteria for myocardial viability (P = 0.027; Hazard risk, HR: 5.1; 95% CI: 1.2-21.4). In the 137 patients who underwent stress-gated SPECT, predictors were scintigraphic criteria for viability plus ischemia (P = 0.026; HR: 3.6; 95% CI: 1.16-11.2) and exercise durationor = 5 minutes (P = 0.04; HR: 2.7; 95% CI: 1.01-7.36). Coronary angiography variables, performed in 111 patients, did not significantly modify the prognostic value of non-invasive testing.Myocardial perfusion-gated SPECT improves prognostic stratification of patients with IC.

Resumen Objetivo La angina cronica previa al infarto (ACPI) de miocardio es una de las expresiones clinicas del precondicionamiento isquemico. Las implicaciones de este fenomeno fisiopatologico han sido objeto de escaso interes en los estudios de gated-SPECT (tomografia computarizada por emision de foton unico) de perfusion miocardica. El objetivo del estudio fue analizar la influencia de la ACPI en el diagnostico de la viabilidad miocardica y el remodelado ventricular izquierdo post-infarto en la gated-SPECT de perfusion miocardica, asi como entre los pacientes sin y con diabetes mellitus. Metodos Se estudiaron consecutivamente 131 pacientes con antecedentes de infarto de miocardio y funcion sistolica deprimida, analizandose las caracteristicas clinicas, electrocardiograficas, ergometricas y de la gated-SPECT de perfusion miocardica entre los enfermos sin (n = 104) y con ACPI (n = 27). Resultados Los pacientes con ACPI se caracterizaron por tener una menor extension de la necrosis miocardica, mas criterios de viabilidad miocardica y menor remodelado ventricular izquierdo (menores volumenes, menor remodelado apical y mayor fraccion de eyeccion) en la gated-SPECT. Entre los pacientes diabeticos sin y con ACPI no se alcanzo la significacion estadistica para la viabilidad, necrosis y remodelado ventricular. Conclusiones La ACPI parece proteger a los pacientes con cardiopatia isquemica de presentar un infarto mas extenso, a expensas de mas criterios gammagraficos de viabilidad miocardica residual.

Desde 1999 no se habia realizado ninguna revision de las Guias de actuacion clinica de la Sociedad Espanola de Cardiologia en Cardiologia Nuclear, por lo que en este articulo exponemos las indicaciones clase I y IIa de la American College of Cardiology/American Heart Association/American Society of Nuclear Cardiology (ACC/AHA/ASNC) con nivel de evidencia A o B, junto con las 27 indicaciones consideradas adecuadas por el Comite de expertos de la American College of Cardiology Foundation/American Society of Nuclear Cardiology (ACCF/ASNC) y los comentarios que hemos considerado oportuno anadir los firmantes de este articulo.

Objective Chronic angina prior to myocardial infarction (CAPMI) is one of the clinical expressions of ischaemic preconditioning. The implications of this physiopathological phenomenon have been of little interest in myocardial perfusion gated SPECT (Single Photon Emission Computed Tomography) studies. The objective was to analyse the influence of CAPMI in the diagnosis of post-infarction myocardial viability and left ventricular remodelling in myocardial perfusion gated SPECT, and between patients with and without diabetes mellitus. Methods 131 patients with history of myocardial infarction and diminished systolic function were studied consecutively, analysing the clinical, electrocardiographic and ergometric characteristics and myocardial perfusion gated SPECT in patients with (n = 27) and without (n = 104) CAPMI. Results Patients with CAPMI were characterised by having a lesser extent of myocardial necrosis, more myocardial viability criteria and less left ventricular remodelling (lower volumes, less apical remodelling and higher EF) on the gated SPECT. Statistical significance for viability, necrosis and ventricular remodelling was not reached between diabetic patients with and without CAPMI. Conclusions CAPMI seems to protect patients with ischaemic cardiopathy from having a more extensive infarction at the expense of more residual myocardial viability scintigraphic criteria.

The purpose of this study was to develop a (1)H-nuclear magnetic resonance metabolomic approach capable of predicting the occurrence of exercise-induced ischemia in patients with suspected coronary artery disease and to identify the metabolite patterns that contribute most importantly to the prediction. In 31 patients with suspected effort angina and without previous myocardial infarction, serum was obtained just prior to a stress single-photon emission computed tomography. Serum NMR spectra were acquired with pulse-and-acquire and T(2)-edited sequences. The region between 0.50 and 4.25 ppm was used for analysis. Twenty-two patients had reversible myocardial perfusion defects and nine did not. Both groups had similar age and clinical profile, except for more smokers and diabetics in the ischemia group, and attained a similar peak heart rate. The best separation was achieved with long T(2)-edited spectra, 84% of patients being correctly classified based on the partial least square discriminant analysis. The main contributors to discrimination were lactate, glucose, as well as methyl and methylene moieties of lipids and long-chain amino acids. Metabolomic analysis of serum can predict exercise-inducible ischemia in patients with suspected coronary artery disease. This capability could be useful in screening and risk stratification of patients with coronary risk factors.

Estudio del efecto pronostico de la revascularizacion coronaria (RC) y del tratamiento medico (TM) en los pacientes con miocardiopatia isquemica y criterios de viabilidad miocardica en la gated-SPECT de perfusion miocardica. Se estudio consecutivamente a 140 pacientes con miocardiopatia isquemica mediante gated-SPECT en reposo con compuestos de tecnecio. Durante un seguimiento medio tras la gated-SPECT de 2,3 anos, la mortalidad cardiaca en los pacientes con RC (n = 50) fue del 16%, y en los que continuaron con TM (n = 90) fue del 26,7%. Asi pues, la RC tuvo un efecto protector (hazard ratio = 0,42; intervalo de confianza del 95%, 0,17-1,02) en los pacientes con miocardiopatia isquemica y criterios de viabilidad.

Introduction and objectives. The objective of this study was to use low-dose dobutamine (LDD) gated single-photon emission computed tomography (SPECT) to evaluate segmental thickening of the left ventricle (LV) and its relationship with changes in ejection fraction (EF) and ventricular volumes in patients with ischemic cardiomyopathy. Methods. This prospective multicenter study involved 89 patients with ischemic cardiomyopathy (ie, EF ≤40%) who underwent LDD gated-SPECT at rest. The LV was divided into 17 segments and systolic thickening was assessed in a total of 1513 segments during LDD infusion. Results. A significant increase in LVEF (33.2% vs 30.8%; P

Study on the effects of coronary revascularization and medical treatment on the prognosis of patients with ischemic cardiomyopathy who satisfy myocardial viability criteria on gated single-photon emission computed tomography (SPECT) assessment of myocardial perfusion. In total, 140 consecutive patients with ischemic cardiomyopathy were studied at rest using gated-SPECT and technetium-labeled contrast agents. During a mean follow-up period of 2.3 years after gated-SPECT, the rate of cardiac death in patients who underwent coronary revascularization (n=50) was 16% compared with 26.7% in those who received medical treatment (n=90). Thus, coronary revascularization had a protective effect (hazard ratio = 0.42; 95% confidence interval, 0.17-1.02) in patients with ischemic cardiomyopathy who satisfied myocardial viability criteria.

Introduction and objectives. Although it is known that the presence of myocardial viability predicts an increase in ejection fraction after revascularization in patients with ischemic cardiomyopathy, little is known about other predictive factors. The aim of this study was to identify variables that can predict an increase in ejection fraction after coronary revascularization surgery in patients with ischemic cardiomyopathy and a viable myocardium. Methods. The study included 30 patients (mean age, 61.6 [11] years, 1 female) with ischemic cardiomyopathy (ejection fraction ≤40%) who fulfilled criteria for myocardial viability. All underwent ECG-gated single-photon emission computed tomography before and after surgery. Results. An increase in ejection fraction ≥5% occurred after surgery in 17 of the 30 patients (56.6%). These patients were characterized by the presence of left main coronary artery disease (P

There are no studies in which diagnostic yield of early rest myocardial perfusion gated single-photon emission computed tomography (SPECT), electrocardiographic exercise testing, and stress SPECT were compared in patients with atypical chest pain, nondiagnostic electrocardiograms (ECGs), and negative markers of myocardial damage in the emergency department. A prospective study of 96 patients who presented with atypical chest pain and nondiagnostic ECG, but without elevated markers of necrosis, was performed. All underwent rest gated SPECT using technetium-99m methoxyisobutyl isonitrile within 6 hours after pain subsided followed by an electrocardiographic exercise test to obtain stress-rest SPECT images. After 1 year, there were no deaths and coronary artery disease was confirmed in only 5 patients. Negative predictive values of the 3 techniques were high (99%, 96%, and 100%, respectively), but positive predictive values were low (27%, 22%, and 14%, respectively). Sensitivities of early SPECT (80%) and stress SPECT (100%) were higher than for the electrocardiographic exercise test (40%). In conclusion, in patients with atypical chest pain, nondiagnostic ECG, and negative biochemical markers, negative predictive values of the 3 tests analyzed are very high. The sensitivity of radionuclide tests is higher, but their widespread use does not appear warranted because their positive predictive value and incidence of complications is low.

Background: We aimed to evaluate the prognostic value of myocardial perfusion gated SPECT in patients with symptomatic intracranial large-artery atherosclerosis (ILA). Methods: Seventy-two consecutive first-ever symptomatic ILA patients without known heart disease underwent a stress myocardial perfusion gated SPECT, and long-term follow-up was conducted thereafter. Results: During an average follow-up of 15.2 ± 9 months, 9 patients (13.8%) presented major coronary events (CEs). Survival analyses (Kaplan-Meier and Cox regression) identified presence of moderate-to-severe myocardial perfusion defects (log rank p = 0.004) and ejection fraction Conclusion: Myocardial perfusion scintigraphy predicts future CEs in patients with symptomatic ILA and may be helpful to guide therapeutic strategies in this subgroup of stroke patients.

Several studies have demonstrated a correlation between myocardial ischemia and severity of coronary lesions as determined by intravascular ultrasound (IVUS) and fractional flow reserve (FFR) measurements. However, their value for the assessment of mild coronary stenoses that are associated with myocardial perfusion abnormalities has not been well studied. The objective of this study was to prospectively compare the results of myocardial perfusion as determined by exercise/dipyridamole myocardial single-photon emission computed tomography with IVUS and FFR measurements in patients who had angiographically mild coronary stenosis (50% diameter stenosis by quantitative coronary angiography). Forty-eight patients who had stable coronary disease (61 +/- 11 years of age; 6 women) were included. All had mild coronary stenosis in the proximal/middle segment ofor = 1 coronary artery and had undergone maximal exercise myocardial technetium-99m tetrofosmin single-photon emission computed tomography within 48 hours before coronary angiography. IVUS measurements included lesion lumen area, external elastic membrane area, lesion plaque burden (calculated as external elastic membrane minus lumen area, divided by external elastic membrane, and multiplied by 100), and lumen area stenosis (calculated as reference lumen area minus lesion lumen area, divided by reference lumen area, multiplied by 100). Fifty-three coronary lesions were studied, with a mean percent diameter stenosis of 34.9 +/- 7.9% on angiography. Myocardial perfusion defects were demonstrated by single-photon emission computed tomography in 11 patients (12 myocardial regions) with no differences in lesion percent diameter stenosis compared with those without perfusion defects. The presence of reversible perfusion defects was associated with a higher lesion plaque burden as evaluated by IVUS (67.4 +/- 8.1% vs 60.2 +/- 9.3%, p = 0.01). FFR values did not differ in the presence or absence of perfusion defects (0.90 +/- 0.06 vs 0.92 +/- 0.07, respectively; p = NS). In conclusion, plaque burden as determined by IVUS may partly explain the presence of myocardial perfusion defects in cases of angiographically nonsignificant coronary lesions. However, the high FFR values associated with these lesions suggest that other mechanisms, such as endothelial/microvascular dysfunction, might also account for perfusion abnormalities in these patients.