Eficacia y seguridad de la terapia de resincronización cardíaca combinada con cardiodesfibrilador implantable para el tratamiento de la insuficiencia cardíaca: metaanálisis de 5.674 pacientes

Objetivo: el propósito de este estudio fue evaluar la eficacia y seguridad de la resincronización cardíaca agregada a la terapia con cardiodesfibrilador implantable (TRC-D) y la terapia con desfibrilador automático implantable (DAI) para el tratamiento de la insuficiencia cardíaca. A esos efectos se realizó un examen sistemático de ensayos controlados aleatorizados. Métodos y resultados: se revisaron las bases de datos de Medline, Embase y la Biblioteca Cochrane en busca de estudios publicados hasta el 31 de mayo de 2012. Se buscó también en las páginas web de clinicaltrials.gov y de la Administración de Alimentos y Medicamentos de EEUU. En el metaanálisis solo se incluyeron ensayos controlados aleatorizados que compararan la eficacia de la TRC-D con la terapia con DAI. Finalmente se incluyeron ocho ensayos controlados aleatorizados de 5.674 pacientes. El metaanálisis puso en evidencia que la terapia con TRC-D se acompañaba de una importante mejoría de las condiciones clínicas [odds ratio (OR): 1,66; 95% intervalo de confianza (IC) 1,33-2,07] y una reducción de la hospitalización (OR: 0,7; IC 95%: 0,6-0,81) y la mortalidad por todas las causas (OR: 0,8; IC 95%: 0,67-0,95). Si bien las ventajas de TRC-D con respecto a DAI resultaron obvias, los eventos adversos periimplantación de TRC-D siguen planteando inquietud. Conclusión: comparado con la terapia con DAI, los pacientes sometidos a TRC-D tienen resultados favorables en cuanto a las mejoras de las condiciones clínicas, la tasa de internaciones y la supervivencia global, pero presentan un riesgo significativamente mayor de eventos adversos periimplantación. Se requieren estudios adicionales para optimizar la aplicación clínica de TRC-D.

Aims: the purpose of this study was to evaluate the efficacy and safety of cardiac resynchronization plus implantable cardioverter defibrillator (CRT-D) therapy and implantable cardioverter defibrillator (ICD) therapy in treating heart failure by systematically reviewing randomized controlled trials. Methods and results: databases of Medline, Embase, and Cochrane Library were searched for published studies up to 31 May 2012. Clinicaltrials.gov and US Food and Drug Administration websites were searched as well. Only randomized controlled trials comparing the efficacy of CRT-D therapy with ICD therapy were enrolled in meta-analysis. Eight randomized controlled trials characterizing 5674 patients were finally included. Meta-analysis found that CRT-D therapy was associated with significant improvement in clinical conditions [odds ratio (OR): 1.66; 95% confidence interval (CI):1.33-2.07] and a reduction in hospitalization (OR: 0.7; 95% CI: 0.6 -0.81) and all-cause mortality (OR: 0.8; 95% CI: 0.67-0.95). Although advantages of CRT-D therapy over ICD therapy were obvious, the peri-implantation adverse events of CRT-D therapy remained to be concerns. Conclusion: compared with ICD therapy, patients receiving CRT-D therapy have favourable outcomes regarding improvement in clinical conditions, hospitalization rate, and overall survival, but at a significantly higher risk of peri-implantation adverse events. Future studies are warranted to optimize the clinical application of CRT-D.

Coronary cyclic flow variations following primary angioplasty is associated with poor short-term prognosis.

AIMS: Recent studies have shown that coronary cyclic flow variations (CCFV) is a platelet-related phenomenon that occurred following reperfusion. Although CCFV predicts acute complications following thrombolytic therapy, its impact following percutaneous coronary interventions (PCI) has not been evaluated yet. METHODS AND RESULTS: One hundred and thirty-one patients with ST-segment Elevation Myocardial Infarction (STEMI) who underwent PCI were included in the analysis. All patients have 24-hour ST-segment monitoring. The development of CCFV was defined as > or = 3 ST-segment transitions (> or =150 microV). We divided the population in two groups according to the presence (n=14, 10.6%) or absence (n=117) of CCFV. The relation between CCFV and 30-day major adverse cardiac events (MACE) was analyzed using a multivariate logistic regression model adjusting for age, sex, diabetes, smoking, anterior infarct, Killip class, and final TIMI flow grade. Clinical and angiographic characteristics were similar between the two groups. Higher 30-day mortality (21.4 vs. 3.8%, p=0.022) and MACE rates (42.9 vs. 10.7%, p=0.005) were seen in the CCFV group. Multivariate regression analysis revealed that patients with CCFV were at increased risk of 30-day MACE (adjusted RR 5.09; 95% CI 1.3-19.1; p=0.0016). CONCLUSION: The presence of CCFV altered primary PCI may provide an early indication of insufficient myocardial perfusion and impending catastrophic outcome.

Protection of Distal Embolization in High-Risk Patients with Acute ST-Segment Elevation Myocardial Infarction (PREMIAR).

Distal embolization may decrease myocardial reperfusion after primary percutaneous coronary intervention (PCI). Nonetheless, results of previous trials assessing the role of distal protection during primary PCI have been controversial. The Protection of Distal Embolization in High-Risk Patients with Acute ST-Segment Elevation Myocardial Infarction Trial (PREMIAR) was a prospective, randomized, controlled study designed to evaluate the role of filter-based distal protection during PCI in patients with acute ST-segment elevation myocardial infarction at high risk of embolic events (including only baseline Thrombolysis In Myocardial Infarction grade 0 to 2 flow). The primary end point was continuous monitoring of ST-segment resolution. Secondary end points included core laboratory analysis of angiographic myocardial blush, ejection fraction measured by cardiac ultrasound, and adverse cardiac events at 6 months. From a total of 194 enrolled patients, 140 subjects were randomized to PCI with or without embolic protection, and 54 were included in a registry arm due to the presence of angiographic exclusion criteria. Baseline characteristics were comparable between arms. The rate of complete ST-segment resolution (>or=70%) at 60 minutes was similar in patients treated with or without distal protection (61.2% vs 60.3%, respectively, p = 0.85). Angiographic myocardial blush (67% vs 70.7%, p = 0.73), in-hospital ejection fraction (47.4 +/- 9.9% vs 45.3 +/- 7.3%, p = 0.29), and combined end point of death, heart failure, or reinfarction at 6 months (14.3% vs 15.7%, p = 0.81) were consistently achieved in a similar proportion in the 2 groups. In conclusion, the use of filter-based distal protection is safe and effectively retrieves debris; however, such use does not translate into an improvement of myocardial reperfusion, left ventricular performance, or clinical outcomes.