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Panstrongylus geniculatus has become the most frequently registered vector of Chagas disease in the metropolitan area of Caracas, Venezuela. This triatomine species has invaded urban areas in recent years and has been implicated in multiple oral outbreaks of Chagas disease in the region. The study of genetic variability and spatial structure in P. geniculatus populations can provide information about possible events of domiciliation and aid intervention programs against triatomine species rapidly adapting to urban ecotopes. We sequenced a region of the cytochrome-b gene in 114 specimens of P. geniculatus from the Metropolitan District of Caracas and assessed patterns of gene flow and phylogenetic relationships among these individuals. A total of 29 haplotypes were detected in the two sampled municipalities, Sucre and Libertador. Though high genetic connectivity was observed between the municipalities (FST = 0.10796; Nm = 11.20), subtle genetic structuring was also observed in particular geographic sub regions. Based on neutrality tests and the observed allele-frequency distribution, the Panstrongylus geniculatus population appears to be expanding and adapting to different microhabitats present in the study area. Our findings affirm the capacity of this insect to adapt to different environments and emphasize its principal role in the epidemiology of Chagas disease in northern Venezuela.

Percutaneous intervention of chronic limb ischemia is often limited by vascular access especially in patients with previous surgical interventions. This warrants development of alternative endovascular techniques, particularly for patients in whom traditional ipsilateral antegrade or contralateral retrograde access has failed or is not possible. We describe a novel approach to the posterior tibial artery using retrograde access with transradial techniques including closure devices in two patients with inaccessible antegrade access.

Aortic stenosis (AS) has been considered an exclusion criterion for the use of the Impella 2.5 catheter. We describe a case in which the Impella catheter was successfully implanted and used for hemodynamic support during balloon aortic valvuloplasty in a high-risk patient of severe AS with a calculated aortic valve area of 0.59 cm2 .

Background Chagas' disease is caused by the protozoan Trypanosoma cruzi and is autochthonous to the Americas. Its distribution depends on triatomine bugs that are responsible for the transmission of the disease. In 2005, we reported the presence of Panstrongylus geniculatus as a risk for Chagas' disease transmission in Caracas and neighboring areas. Three massive oral outbreaks occurred in the following years. Here we report the results of a 7-year study on triatomine species found in the Metropolitan District of Caracas (MDC), Venezuela. Methods Triatomine species collected by inhabitants of Caracas during 7 years were analyzed for parasite infection and blood meal. Triatomines were found in 31 of the 32 parishes surveyed. Traitomines were examined for the presence of blood and parasites in the digestive tract. Molecular techniques were used for the typing of parasites. Results A total of 3551 triatomines were captured from 31 of the 32 parishes surveyed. The vast majority of these were identified as P. geniculatus (98.96%), followed by Triatoma nigromaculata (0.59%), Triatoma maculata (0.39%) and Rhodnius prolixus (0.06%). Triatomines were always most abundant between April and June, and 2010 showed the highest number. We found that 54% of the specimens were females, 42.5% males and 3.5% nymphs. Overall, 75.2% of the insects were naturally infected with T. cruzi and 48.7% had fed on blood. Analysis of the adult forms showed that 60% of the females and 31.9 % of the males had blood in their stomachs, and 77.5% of the females and 73.3% of the males were naturally infected with T. cruzi. Nearly all, 99.6% of the T. cruzi isolates analyzed belonged to the TcI genotype. Conclusions Blood-fed triatomine bugs infected with T. cruzi were distributed throughout Caracas. Four different species of triatomines were identified of which P. geniculatus was by far the most predominant. Our previous report of Eratyrus mucronatus raises the number of triatomine species in the MDC to 5. Dramatic modifications to the surrounding natural habitats have led to the establishment of a T. cruzi urban enzootic cycle, resulting in a high risk for Chagas' disease transmission in this capital city. Electronic supplementary material The online version of this article (doi:10.1186/s13071-014-0602-7) contains supplementary material, which is available to authorized users.

Transcatheter aortic valve replacement has emerged as an alternative option for inoperable or very high-risk patients with severe aortic stenosis-however, there are serious complications associated with the procedure, such as patient mortality, stroke, conduction disturbances, paravalvular regurgitation, and vascular concerns. Our review focuses on the most common complications related to transcatheter aortic valve replacement procedures and potential bailout strategies and techniques.

Objectives To evaluate feasibility and technical outcomes in patients with aortic stenosis (AS) who have undergone high-risk procedures with continuous flow left ventricular (LV) assist, with the Impella 2.5 system (Abiomed, Danvers, MA). Background In preparation for transcatheter aortic valve implantation, an increasing number of high-risk patients with severe AS and left ventricular dysfunction are currently considered for percutaneous coronary interventions (PCI) and balloon aortic valvuloplasty (BAV). Hemodynamic support may be required in some patients. Methods We reviewed procedural and clinical findings and 30-day outcomes in patients with symptomatic AS who underwent high-risk percutaneous procedures supported by the Impella 2.5 system. All patients carried a high-risk of operative mortality. Impella was used during PCI, BAV, and for hemodynamic support during emergencies. Results Over a 14-month period, 21 patients with AS underwent insertion of Impella prior to high-risk PCI (n = 3), BAV with subsequent PCI (n = 8), BAV alone (n = 7), or during cardiac arrest immediately following BAV (n = 3). The mean Society of Thoracic Surgeons (STS) predicted mortality risk was 14% (range 7.3–24.7%). Impella was inserted successfully in all patients attempted. Retrograde advancement of two catheters across the aortic valve (for concomitant BAV in 15 patients) was technically feasible. Retrograde continuous flow LV assist produced a reduction in LV end-diastolic pressure and an increase in arterial pressure. Periprocedural complications occurred in 19% (n = 4) patients, with no periprocedural deaths. Mortality at 30 days was 14.2%. Conclusion Our data suggests that continuous flow LV assist with Impella 2.5 can be used in high-risk patients with severe AS who require periprocedural hemodynamic support. © 2012 Wiley Periodicals, Inc.

Chronic total occlusions remain a technical challenge for interventional cardiologists. This group of lesions carries a decreased rate of success and continues to be an important reason for surgical revascularization. Recently, retrograde percutaneous coronary intervention of total occlusions via epicardial and septal perforators was introduced as an alternative approach when a previous antegrade attempt has failed. We describe a unique case where retrograde approach was used as the initial recanalization technique in the absence of a right coronary ostium. V C 2011 Wiley-Liss, Inc.

Context: Octogenarians are the fastest growing segment of the population and little is known about the results of cardiopulmonary resuscitation (CPR) after in-hospital cardiac arrest in this population. Objective: We sought to investigate the clinical benefit and cost-effectiveness of CPR after in-hospital cardiac arrest in octogenarians. Main Outcome Measure: Years of life saved. Design: Effectiveness data were obtained from a review of 91,372 hospital discharges from January 1st, 1993 until June 30th, 1996. Cardiac arrest was reported in 956 patients. The study group consisted of 474 patients ≧80 years old. CPR costs included equipment and training, physician and nursing time and medications. Post-CPR expenses included in-hospital true cost, repeat hospitalizations, physician office visits, nursing home, rehabilitation, and chronic care hospital costs. Life expectancy of the patients who were still alive at the end of the study was estimated from census data. A utility of 0.8 was used to calculate quality-adjusted-life years saved (QALYS). We used a societal perspective for analysis. Results: The study population was 86 ± 4.8 years old (range 80–103), and 42% were male. Fifty-four patients (11%) were discharged alive, 35 to a chronic care facility and 19 to their home. Assuming that a cardiac arrest without CPR has 100% mortality, 12 octogenarians required treatment with CPR in order to save one life to hospital discharge. Similarly, 29 octogenarian patients with cardiac arrest have to be treated with CPR to net one long-term survivor (mean survival 21 months, with a range from 9 to 48 months). The cost-effectiveness ratio, after estimating the life expectancy of octogenarian survivors, was USD 50,412 per year of life saved, and USD 63,015 per QALYS. However, a utility of 0.5 yielded a cost of USD 100,825 per QALYS. Conclusion: In comparison with other life-saving strategies, CPR in octogenarians is effective. The favorable cost-effectiveness ratio is highly dependent on the patients’ preference for quality rather than quantity of life, as expressed by the utility assumptions.