Performance and clinical comparison between left ventricular quadripolar and bipolar leads in cardiac resynchronization therapy: Observational research

Aim To evaluate Attain Performa (Medtronic, Dublin, Ireland) quadripolar lead performance in clinical practice and, secondarily, to compare its long term clinical outcomes vs bipolar leads for left ventricular (LV) pacing. Methods and results We retrospectively analyzed clinical, procedural and follow-up data of 215 patients implanted with a quadripolar lead. One hundred and twenty one patients implanted with bipolar lead were selected to compare long-term clinical outcomes. The quadripolar lead was implanted in the target vein in 196 patients (91%) without acute dislodgements. In 50% of patients the chosen final pacing configuration at implant would not have been available with bipolar leads. A dedicated quadripolar pacing vector was chosen more frequently when the LV tip location was apical than otherwise (65.6% vs 42.7%, p = 0.003). After a median follow-up of 14 months, the LV pacing threshold was less than 2.5 V at 0.4 ms in 98 patients (90%) with a safety margin between phrenic nerve and LV pacing threshold >3 V in 97 patients (89%). We observed a slight trend toward a lower risk of heart failure worsening and a lower incidence of ventricular arrhythmias and pulmonary congestion in patients implanted with quadripolar leads compared with the control group. Conclusion Quadripolar leads improve the management of phrenic nerve stimulation at no trade-off with pacing threshold and lead stability. Quadripolar leads seems to be associated with a lower incidence of VT/VF and pulmonary congestion, when compared with bipolar leads, but further investigations are necessary to confirm that this positive effect is associated with better LV reverse remodeling.

Resultados de pacientes con terapia de resincronización cardíaca utilizando un electrodo cuadripolar en el ventrículo izquierdo

La terapia de resincronización cardíaca (TRC) es un método terapéutico bien establecido para el tratamiento de pacientes con insuficiencia cardíaca. La TRC revierte la remodelación del ventrículo izquierdo (VI) dilatado en pacientes sintomáticos con una función sistólica deprimida y complejos QRS anchos, a pesar de recibir una terapia farmacológica óptima, mejorando la clase funcional y reduciendo tanto la sintomatología como la morbilidad, la mortalidad y la hospitalización. La proporción de pacientes que no responden a la TRC se estima en alrededor del 20-40%, según algunos estudios, asociándose a una tasa de complicaciones no despreciables, como son los desplazamientos de electrodos y la estimulación diafragmática. Estudios recientes sugieren que la TRC con un electrodo cuadripolar (EC) en el VI está asociada con excelentes umbrales de estimulación, bajas tasas de desplazamiento de estimulación del nervio frénico y mejora en el gasto cardíaco, en el seguimiento a corto y mediano plazo. Por último, serán necesarios estudios randomizados comparando EC con catéteres bipolares convencionales para evaluar la eficacia, complicaciones y el costo-eficacia.

Results of patients with cardiac resynchronization therapy using a quadripolar left ventricular lead Cardiac resynchronization therapy (CRT) is a well-established therapeutic for the treatment of patients with heart failure. CRT reverses remodelling of the dilated left ventricle (LV) and reduces morbidity and mortality in patients with symptomatic heart failure, prolonged electrical delay, and impaired systolic function receiving optimal pharmacological therapy, enhancing the functional class and reducing the symptoms and morbidity, mortality and hospitalization. The proportion of patients who do not respond to CRT is estimated at about 20-40%, according to some studies associated to a not insignificant complication rate, such as dislocation and phrenic nerve stimulation (PNS). Recent studies suggest that CRT with a quadripolar left ventricular (LV) lead results in excellent pacing thresholds, low rates of dislocation, PNS and improvement in cardiac output at short-term and at medium-term follow-up. Finally, it will be necessary quadripolar LV lead randomized trials comparing conventional bipolar catheter to assess the efficacy, complications and cost-effectiveness.

Resultados de pacientes com terapia de ressincronização cardíaca utilizando um eletrodo quadripolar no ventrículo esquerdo A terapia de ressincronização cardíaca (TRC) é uma abordagem terapêutica bem estabelecida para o tratamento de pacientes com insuficiência cardíaca. A TRC reverte remodelamento do ventrículo esquerdo (VE) em pacientes sintomáticos com função sistólica deprimida dilatada e complexos QRS largos, apesar de receber tratamento medicamentoso otimizado, melhorando a classe funcional e reduzindo os sintomas e a morbidade, mortalidade e hospitalização. A proporção de pacientes que não respondem a TRC é estimada em cerca de 20-40%, de acordo com alguns estudos, associado a uma taxa de complicação não insignificante, como o deslocamento de eletrodos e estimulação do nervo frênico (ENF). Estudos recentes sugerem que a TRC com eletrodo quadripolar (EQ) no VE está associada com excelentes limiares de estimulação, baixas taxas de deslocamento, ENF e melhor monitorização do débito cardíaco, a curto e médio prazo. Finalmente, serão necessários ensaios clínicos randomizados que comparam EQ com cateter bipolar convencional para avaliar a eficácia, as complicações e custo-efetividade.

O-X Flap; Quadripolar Advancement Flap / 대한피부과학회지

Large surgical defects are often difficult to repair and extensive adjacent skin transfer may be necessary. The purse-string suture can be used to reduce the size of large defects, but a second intervention may be necessary and requires several weeks for complete healing. Therefore, reconstruction of large defects is a challenge to the dermatologist. We report a case of basal cell carcinoma on the back in which the skin defect was reconstructed by a quadripolar advancement flap. Because the large O-shaped defect resulted in an X-shaped closure, we named this flap the O-X flap.

Static magnets: what are they and what do they do? / Magnetos estáticos: o que são e para que servem?

INTRODUCTION: Therapeutic static magnets have gained wide community acceptance for neuromusculoskeletal pain relief in many countries yet, apart from strong anecdotal reports of benefit, there is a paucity of scientific evidence for their use. OBJECTIVES: In this review we describe the physical characteristics of traditional and commonplace unipolar and bipolar static magnets as well as newer quadripolar magnetic arrays; discuss what is known of the physiological effects of static magnets and the strength of the literature; and make suggestions for targeted future research for static magnets in the management of neuromusculoskeletal pain conditions.

INTRODUÇÃO: A magnetoterapia estática conquistou ampla aceitação da comunidade para alívio da dor neuromusculoesquelética em diversos países. No entanto, com exceção de relatórios anedóticos de seus benefícios, há uma grande escassez de evidências científicas para seu uso. OBJETIVOS: Nesta revisão, descrevemos as características físicas dos tradicionais magnetos estáticos unipolares e bipolares comuns, assim como os mais recentes conjuntos magnéticos quadripolares; discutimos o que se conhece sobre os efeitos fisiológicos da magnetoterapia estática e o suporte da literatura; e fazemos sugestões para futuras pesquisas direcionadas à magnetoterapia estática no controle de condições de dor neuromusculoesquelética.