RESUMO
AIMS: Excessive prolongation of PR interval impairs coupling of atrio-ventricular (AV) contraction, which reduces left ventricular pre-load and stroke volume, and worsens symptoms. His bundle pacing allows AV delay shortening while maintaining normal ventricular activation. HOPE-HF evaluated whether AV optimized His pacing is preferable to no-pacing, in a double-blind cross-over fashion, in patients with heart failure, left ventricular ejection fraction (LVEF) ≤40%, PR interval ≥200 ms and either QRS ≤140 ms or right bundle branch block. METHODS AND RESULTS: Patients had atrial and His bundle leads implanted (and an implantable cardioverter-defibrillator lead if clinically indicated) and were randomized to 6 months of pacing and 6 months of no-pacing utilizing a cross-over design. The primary outcome was peak oxygen uptake during symptom-limited exercise. Quality of life, LVEF and patients' holistic symptomatic preference between arms were secondary outcomes. Overall, 167 patients were randomized: 90% men, 69 ± 10 years, QRS duration 124 ± 26 ms, PR interval 249 ± 59 ms, LVEF 33 ± 9%. Neither peak oxygen uptake (+0.25 ml/kg/min, 95% confidence interval [CI] -0.23 to +0.73, p = 0.3) nor LVEF (+0.5%, 95% CI -0.7 to 1.6, p = 0.4) changed with pacing but Minnesota Living with Heart Failure quality of life improved significantly (-3.7, 95% CI -7.1 to -0.3, p = 0.03). Seventy-six percent of patients preferred His bundle pacing-on and 24% pacing-off (p < 0.0001). CONCLUSION: His bundle pacing did not increase peak oxygen uptake but, under double-blind conditions, significantly improved quality of life and was symptomatically preferred by the clear majority of patients. Ventricular pacing delivered via the His bundle did not adversely impact ventricular function during the 6 months.
Assuntos
Terapia de Ressincronização Cardíaca , Insuficiência Cardíaca , Masculino , Humanos , Feminino , Fascículo Atrioventricular , Estudos Cross-Over , Volume Sistólico , Qualidade de Vida , Tolerância ao Exercício , Função Ventricular Esquerda , Oxigênio , Resultado do Tratamento , Estimulação Cardíaca Artificial/métodos , Terapia de Ressincronização Cardíaca/métodos , Eletrocardiografia/métodosRESUMO
OBJECTIVES: This study sought to test specialized processing of laser Doppler signals for discriminating ventricular fibrillation (VF) from common causes of inappropriate therapies. BACKGROUND: Inappropriate implantable cardioverter-defibrillator (ICD) therapies remain a clinically important problem associated with morbidity and mortality. Tissue perfusion biomarkers, implemented to assist automated diagnosis of VF, sometimes mistake artifacts and random noise for perfusion, which could lead to shocks being inappropriately withheld. METHODS: The study tested a novel processing algorithm that combines electrogram data and laser Doppler perfusion monitoring as a method for assessing circulatory status. Fifty patients undergoing VF induction during ICD implantation were recruited. Noninvasive laser Doppler and continuous electrograms were recorded during both sinus rhythm and VF. Two additional scenarios that might have led to inappropriate shocks were simulated for each patient: ventricular lead fracture and T-wave oversensing. The laser Doppler was analyzed using 3 methods for reducing noise: 1) running mean; 2) oscillatory height; and 3) a novel quantification of electromechanical coupling which gates laser Doppler relative to electrograms. In addition, the algorithm was tested during exercise-induced sinus tachycardia. RESULTS: Only the electromechanical coupling algorithm found a clear perfusion cut off between sinus rhythm and VF (sensitivity and specificity of 100%). Sensitivity and specificity remained at 100% during simulated lead fracture and electrogram oversensing. (Area under the curve running mean: 0.91; oscillatory height: 0.86; electromechanical coupling: 1.00). Sinus tachycardia did not cause false positive results. CONCLUSIONS: Quantifying the coupling between electrical and perfusion signals increases reliability of discrimination between VF and artifacts that ICDs may interpret as VF. Incorporating such methods into future ICDs may safely permit reductions of inappropriate shocks.
Assuntos
Desfibriladores Implantáveis , Cardioversão Elétrica , Eletrocardiografia , Falha de Equipamento , Fluxometria por Laser-Doppler , Processamento de Sinais Assistido por Computador , Fibrilação Ventricular/diagnóstico , Idoso , Algoritmos , Técnicas Eletrofisiológicas Cardíacas , Exercício Físico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Taquicardia SinusalRESUMO
Although permanent His bundle pacing was first reported almost 2 decades ago, it is only recently gaining wider adoption, following facilitation of the implant procedure by dedicated tools. An additional challenge is programming the system, as His bundle pacing may have specific configurations and require special considerations which current implantable pulse generators are not designed for. The aim of this article is to provide practical recommendations for programming His bundle pacing, to deliver optimal therapy and ensure patient safety.
Assuntos
Potenciais de Ação , Arritmias Cardíacas/terapia , Fascículo Atrioventricular/fisiopatologia , Estimulação Cardíaca Artificial/métodos , Insuficiência Cardíaca/terapia , Marca-Passo Artificial , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/fisiopatologia , Eletrocardiografia , Técnicas Eletrofisiológicas Cardíacas , Desenho de Equipamento , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/fisiopatologia , Frequência Cardíaca , Humanos , Valor Preditivo dos Testes , Processamento de Sinais Assistido por Computador , Fatores de Tempo , Resultado do TratamentoRESUMO
Migraine headaches are frequent in adolescents. Although many adolescents are adequately treated palliatively with analgesics, an important subgroup requires prophylactic treatment. Medical treatments for adolescents with frequent severe headaches is often problematic. Prophylactic pharmacological treatments are often shunned by adolescents and their parents because of concern over drug usage. Moreover, propranolol, the most widely used prophylactic drug with adults, is frequently not effective. Psychological interventions are effective but are costly and often not available. A randomized controlled trial was undertaken to evaluate the efficacy and efficiency of a predominantly self-administered treatment that could be delivered in a very cost-efficient format. Eighty seven adolescents (63 females and 24 males) ranging in age from 11 to 18 years were randomly assigned to receive a self-administered treatment, the same treatment delivered by a therapist or a control treatment. Self-administered and clinic treatment were equally effective and superior to the control treatment. However, the self-administered treatment was substantially more efficient. Both active treatments were durable at 1-year follow-up.
Assuntos
Terapia Cognitivo-Comportamental , Transtornos de Enxaqueca/terapia , Adaptação Psicológica , Adolescente , Criança , Depressão/psicologia , Feminino , Humanos , Masculino , Transtornos de Enxaqueca/psicologia , Terapia de RelaxamentoRESUMO
The present study compared the efficacy of two active treatments, relaxation training and cognitive coping, with a non-specific placebo control in the treatment of 42 children and adolescents with migraine. The first treatment is a simplified version of progressive deep muscle relaxation; the second, a form of cognitive restructuring involving the alteration of dysfunctional thought processes. The results demonstrated that each active treatment was superior to the non-specific intervention in reducing overall headache activity and frequency but not duration or intensity. There were no differences between the experimental groups, and both continued to improve through a 16-week follow-up period, but the control group did not. Initial level of headache severity was an important factor in treatment outcome, with children with severe headaches responding better than those with milder headaches. Possible reasons for the differential treatment effects are discussed, and the implications for future research are considered.