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Background: Securing transvenous left ventricular (LV) pacing leads without an active fixation mechanism in proximal coronary vein (CV) segments is usually challenging and frequently impossible. We investigated how active fixation leads can be safely implanted in this location, how to avoid perforating the free wall of the CV, and how to recognize and respond to perforations. Materials and Methods: In five patients with no alternative to LV pacing from proximal CV segments, 4 Fr SelectSecure (Medtronic, Minneapolis, MN, USA) leads, which have a fixed helix, were implanted through a modified 6 Fr guide catheter with a pre-shaped tip (Launcher, Medtronic). Results: Active fixation leads were successfully implanted in proximal CVs in five patients. There were no complications. Acute and chronic pacing thresholds were comparable to those of conventional CV leads. The pre-shaped guide catheter tip remains in close proximity to the myocardial aspect of the CV, directing the lead helix toward a safe implantation site. Conclusions: If only proximal CV pacing sites are available, 4 Fr SelectSecure leads can be safely implanted through a modified Launcher guide catheter, avoiding more invasive implantation techniques. Other than venous stenting or implantation of leads with retractable tines, SelectSecure leads are expected to remain extractable. [ABSTRACT FROM AUTHOR]

This multicenter longitudinal observational trial was designed to analyze the long-term outcome of patients with heart failure (HF) treated with cardiac resynchronization therapy (CRT) alone or with implantable cardioverter-defibrillator (ICD) backup in a daily practice scenario. It is unknown whether the magnitude of survival benefits conferred by CRT in a daily practice scenario is comparable to what has been observed in randomized controlled trials and whether this benefit is sustained over the long term. The outcome of 1,303 consecutive patients with ischemic or nonischemic cardiomyopathy on optimal pharmacologic therapy treated from August 1, 1995 to August 1, 2004 at 4 European centers with CRT alone (44%) or with ICD backup for symptomatic HF and prolonged QRS duration was assessed. Cumulative event-free survival was evaluated for a combined end point, defined as death from any cause, urgent transplantation, or implantation of a left ventricular assist device. The cumulative incidence of competing events, HF, sudden cardiac death, and noncardiac death, was also assessed. Event-free survival was similar across the different centers. At 1 and 5 years, cumulative event-free survivals were 92% (95% confidence interval [CI] 91 to 94) and 56% (95% CI 48 to 64), respectively. The cumulative incidence of HF deaths was 25.1% (95% CI 19 to 31.7), whereas that of sudden death was 9.5% (95% CI 5.1 to 15.7). Using multivariate analysis, CRT with an ICD backup was associated with a nonsignificant decrease in mortality by 20% (hazard ratio 0.83, 95% CI 0.58 to 1.17, p = 0.284), with a highly significant protective effect against sudden cardiac death (hazard ratio 0.04, 95% CI 0.04 to 0.28, p <0.002). In conclusion, patients with advanced HF and a wide QRS complex routinely treated with CRT have a favorable long-term outcome that was reproducible at different centers. The leading cause of death in these patients remained HF, and this mode of death was competing with other causes in determining outcome. Total mortality was 20% lower with ICD backup (95% CI 42% lower to 17% higher) due to a protective effect against sudden cardiac death. [Copyright &y& Elsevier]

Global drought projections are commonly based on Global Climate Models (GCMs), which can provide reliable prediction at medium or low spatial resolution. Instead, the use of Regional Climate Models (RCMs) and Empirical Statistical Downscaling (ESD), driven by GCMs, can provide information at higher spatial resolution, thus addressing the regional climate patterns, which can be very important especially over areas with complex orography. Using a large ensemble of 103 simulations (derived from the combination of 16 GCMs and 20 RCMs) at spatial resolution of 0.44°, we analyzed how drought frequency and severity is projected to change from 1981-2010 to the end of 21st century under two climate scenarios, the moderate RCP4.5 and the more extreme RCP8.5. Moreover, we focused on the probability of occurrence, in 2071-2100, of extreme drought events never recorded in the last decades. To obtain the drought metrics, we started from the Standardized Precipitation Index (SPI) and the Standardized Precipitation-Evapotranspiration Index (SPEI), both computed at 12-month accumulation scale. We identified the following drought hotspots, where the events are projected to become progressively more frequent and severe as the century passes: North Americas West Coast and the Dominican Republic, Chile and southwestern Argentina, the Mediterranean Region, parts of Congo, Angola, South Africa, Namibia and Madagascar, Southeastern China, Japan, southwestern Australia and Tasmania. We discuss on the importance of including (or not) temperature (and evapotranspiration) as climate driver of meteorological drought (and not only precipitation): in particular, the future drought tendency depends on this choice over large parts of North America, Amazonia, central Europe, central Asia, the Horn of Africa, and central Australia. [ABSTRACT FROM AUTHOR]