RESUMO
BACKGROUND: Left bundle branch area pacing (LBBAP) has swiftly emerged as a safe and effective alternative to right ventricular pacing. Limited data exist on the use of retractable-helix, stylet-driven leads for LBBAP. OBJECTIVE: The objective of this study was to prospectively evaluate the performance and safety of a stylet-driven pacing lead in a rigorously controlled multicenter trial to support US market application. METHODS: A multicenter, prospective, nonrandomized trial enrolled patients with standard pacing indications. Implant procedure and lead data, including threshold, sensing, impedance, and capture type, were collected through 3 months. Primary end points were freedom from LBBAP lead-related serious complications through 3 months and LBBAP implant success according to prespecified criteria. A blinded clinical events committee adjudicated all potential end point complications. RESULTS: A total of 186 patients were included from 14 US sites. LBBAP implants were successful in 95.7% (178 of 186; 95% confidence interval 91.7%-98.1%; P < .0001 for comparison to the performance goal of 88%). Through the 3-month follow-up visit, 3 patients (1.7%) experienced a serious LBBAP complication (all lead dislodgments), resulting in a LBBAP lead-related complication-free rate of 98.3%. A total of 13 patients (7.8%) experienced any system- or procedure-related complication. The mean threshold was 0.89 V at 0.4 ms, the sensing value was 10.8 mV, and impedance was 608 Ω. CONCLUSION: The short-term results from this prospective trial demonstrate both high implant success and freedom from LBBAP lead-related complications using this stylet-driven retractable helix lead. This trial supports the safety, use, and effectiveness of stylet-driven leads for performing contemporary physiologic pacing.
RESUMO
This case describes some of the commonly overlooked device-related issues in patients who have reportedly failed to respond to cardiac resynchronization therapy (CRT). The case demonstrates voltage-dependent right ventricular capture instead of right atrial capture by a subtly malpositioned right atrial lead. CRT therapy failed to improve symptoms of heart failure and the diagnosis of "CRT nonresponder" was made. With a detailed fact-finding approach, the mechanism behind this nonresponse was identified, and the outcome of CRT was significantly improved with rectification of the problems.
RESUMO
Pyogenic liver abscesses are rare in children, and show geographical differences in their epidemiology. Mortality rates remain high at 15 %. Liver abscesses caused by anaerobic organisms are rare in a paediatric setting, even more so when complicated by portal vein thrombosis (PVT). A 6-year-old girl, previously fit and well, was admitted with fever, lethargy and weight loss of 2 weeks duration. The patient was febrile on examination and a review of the systems revealed no positive findings. An abdominal ultrasound scan showed multiple interconnecting cystic lesions consistent with liver abscesses, which was confirmed by a computed tomography scan. Aspirate of the abscess was cultured, resulting in the isolation of a non-haemolytic anaerobic organism, which was difficult to identify using conventional phenotypic identification tests. 16S rRNA typing identified the organism as Clostridium clostridioforme. The liver abscess in our patient displayed a particularly aggressive clinical course with extension of the abscess to involve the upper pole of the right kidney and the appendix, which was further complicated by PVT. The role of anaerobic organisms in liver abscesses has been underreported in the past. This case, therefore, highlights the importance of incubating biological samples in anaerobic conditions in order to adequately isolate and identify anaerobic bacteria, particularly those associated with abscesses.
