Abstract:
OBJECTIVES:We hypothesized that combining biphasic waveform and sequential pulse defibrillation techniques would lower the defibrillation threshold of a nonthoracotomy lead system in humans below that obtained with biphasic or sequential pulse defibrillation alone. BACKGROUND:Previous studies have shown that sequential pulse monophasic shocks and biphasic waveform shocks are more effective than single monophasic shocks for ventricular defibrillation. METHODS:Thirteen patients aged 48 to 71 years undergoing nonthoracotomy defibrillation lead testing participated in the study. Transvenous electrodes were positioned in the right ventricular apex, superior vena cava and coronary sinus. A cutaneous patch electrode was placed on the left chest wall. All electrodes were connected to an external defibrillator. In random order, defibrillation threshold measurements were made for biphasic defibrillation alone, sequential defibrillation alone and combined biphasic plus sequential defibrillation. RESULTS:The mean defibrillation threshold-delivered energy was 18.0 +/- 11.9 J for biphasic defibrillation and 16.3 +/- 9.0 J for sequential defibrillation. Biphasic plus sequential defibrillation significantly reduced the threshold energy to 10.2 +/- 5.3 J (p < 0.001). Threshold peak voltage and current values showed corresponding reductions. The combined waveform resulted in a greater reduction in defibrillation threshold in patients with threshold energies > 18 J versus those with threshold values < or = 18 J for sequential (p = 0.001) or biphasic (p < 0.01) waveform alone. The nonthoracotomy lead implantation rate was improved from 62% with each of the single techniques (biphasic waveform or sequential pulse defibrillation) to 85% with the combined waveform. CONCLUSIONS:Adding biphasic waveform to sequential pulse defibrillation significantly reduced the defibrillation threshold compared with either technique alone, and nonthoracotomy lead system implantation can be enhanced by this combined technique.
journal_name
J Am Coll Cardioljournal_title
Journal of the American College of Cardiologyauthors
Exner D,Yee R,Jones DL,Klein GJ,Mehra Rdoi
10.1016/0735-1097(94)90413-8subject
Has Abstractpub_date
1994-02-01 00:00:00pages
317-22issue
2eissn
0735-1097issn
1558-3597pii
0735-1097(94)90413-8journal_volume
23pub_type
临床试验,杂志文章,随机对照试验abstract::In a previous study, a significant inverse relation was found between the luminal size of aortocoronary venous bypass grafts and the vascular resistance of the coronary region that was perfused by the bypass graft in late stages after bypass surgery. This observation suggested that changes in the graft-dependent vascu...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章
doi:10.1016/s0735-1097(87)80153-5
更新日期:1987-07-01 00:00:00
abstract:BACKGROUND:Heart failure patients with primary prevention implantable cardioverter-defibrillators (ICD) may experience an improvement in left ventricular ejection fraction (LVEF) over time. However, it is unclear how LVEF improvement affects subsequent risk for mortality and sudden cardiac death. OBJECTIVES:This study...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章,多中心研究
doi:10.1016/j.jacc.2015.05.057
更新日期:2015-08-04 00:00:00
abstract:OBJECTIVES:We evaluated the relationship between acute hemodynamic response (AHR) and reverse remodeling (RR) in cardiac resynchronization therapy (CRT). BACKGROUND:CRT reduces mortality and morbidity in heart failure patients; however, up to 30% of patients do not derive symptomatic benefit. Higher proportions do not...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章
doi:10.1016/j.jacc.2011.04.042
更新日期:2011-09-06 00:00:00
abstract:OBJECTIVES:We sought to test the hypothesis that complex fractionated electrograms (CFAEs) recorded during atrial fibrillation (AF) could be used as target sites for catheter ablation of AF. BACKGROUND:Mapping of AF in humans has shown that areas of CFAEs correlate with areas of slowed conduction and pivot points of r...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章
doi:10.1016/j.jacc.2003.12.054
更新日期:2004-06-02 00:00:00
abstract::The combined clinical and pathophysiologic characteristics and diagnostic features as well as current concepts of pathogenesis, therapy and prevention of the principal forms of cardiomyopathy are reviewed. These include hypertrophic cardiomyopathy, dilated cardiomyopathy, restrictive cardiomyopathy and specific cardia...
journal_title:Journal of the American College of Cardiology
pub_type: 历史文章,杂志文章,评审
doi:10.1016/0735-1097(89)90293-3
更新日期:1989-05-01 00:00:00
abstract:OBJECTIVES:We examined whether mitral regurgitation (MR) augments post-myocardial infarction (MI) remodeling. BACKGROUND:MR doubles mortality after MI, but its additive contribution to left ventricular (LV) remodeling is debated and has not been addressed in a controlled fashion. METHODS:Apical MIs were created in 12...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章
doi:10.1016/j.jacc.2007.07.093
更新日期:2008-01-29 00:00:00
abstract:OBJECTIVES:We investigated whether the presence of right ventricular (RV) abnormalities detected by cardiovascular magnetic resonance (CMR) predict adverse outcome in patients presenting with frequent premature ventricular complexes (PVCs) of left bundle branch block (LBBB) morphology. BACKGROUND:CMR is a component of...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章
doi:10.1016/j.jacc.2010.03.087
更新日期:2010-10-05 00:00:00
abstract:OBJECTIVES:The aim of this study was to investigate whether multiple biomarkers contribute to improved coronary heart disease (CHD) risk prediction in post-menopausal women compared with assessment using traditional risk factors (TRFs) only. BACKGROUND:The utility of newer biomarkers remains uncertain when added to pr...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章
doi:10.1016/j.jacc.2009.12.047
更新日期:2010-05-11 00:00:00
abstract:OBJECTIVES:The present study sought to determine the value of fractional flow reserve (FFR) compared with stress perfusion scintigraphy (SPS) in patients with recent unstable angina/non-ST-segment elevation myocardial infarction (UA/NSTEMI). BACKGROUND:Fractional flow reserve, an invasive index of stenosis severity, i...
journal_title:Journal of the American College of Cardiology
pub_type: 临床试验,杂志文章,随机对照试验
doi:10.1016/s0735-1097(03)00057-3
更新日期:2003-04-02 00:00:00
abstract::Poorly controlled type 2 diabetes mellitus is associated with the development of cardiovascular and renal complications, resulting in significant morbidity and mortality. Intensive glycemic control has been a major focus for clinical trials and novel drug development. However, narrow treatment strategies developed str...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章,评审
doi:10.1016/j.jacc.2019.09.022
更新日期:2019-11-19 00:00:00
abstract:BACKGROUND:Early pathogenesis of diabetic cardiomyopathy (DMCM) may involve lipotoxicity of cardiomyocytes in the context of hyperglycemia. There are many preclinical studies of DMCM pathogenesis, but the human evidence is still poorly understood. OBJECTIVES:By using a nondiabetic mellitus (non-DM) heart transplanted ...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章
doi:10.1016/j.jacc.2020.01.018
更新日期:2020-03-24 00:00:00
abstract:OBJECTIVES:The purpose of this study was to determine whether alterations in cardiac structure or function contribute to the increased risk associated with renal impairment after myocardial infarction (MI). BACKGROUND:Renal impairment is associated with adverse cardiovascular outcomes after MI. METHODS:Echocardiograp...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章,随机对照试验
doi:10.1016/j.jacc.2007.06.018
更新日期:2007-09-25 00:00:00
abstract::To test the hypothesis that the human sinus node is capable of demonstrating multiple sites of impulse generation, we assessed spontaneous shifts in the sinus node pacemaker complex, and shifts after overdrive atrial pacing, premature atrial stimulation and carotid sinus massage. A total of 24 patients aged 59 +/- 15 ...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章
doi:10.1016/s0735-1097(87)80081-5
更新日期:1987-01-01 00:00:00
abstract:OBJECTIVES:We examined the possible effect of neuropeptide Y in modulating central sympathetic activity after myocardial infarction in rats. BACKGROUND:Previous studies have shown the coexistence of neuropeptide Y and norepinephrine in the brain and a possible functional interaction between the two. Neuropeptide Y inh...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章
doi:10.1016/0735-1097(96)00063-0
更新日期:1996-06-01 00:00:00
abstract:OBJECTIVES:We investigated coagulation abnormalities in out-of-hospital cardiac arrest (OHCA) patients, with special attention to the protein C anticoagulant pathway. BACKGROUND:Successfully resuscitated cardiac arrest is followed by a systemic inflammatory response and by activation of coagulation, both of which may ...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章
doi:10.1016/j.jacc.2005.03.046
更新日期:2005-07-05 00:00:00
abstract:OBJECTIVES:We evaluated left atrial appendage obliteration in high-risk patients with atrial fibrillation (AF). BACKGROUND:Left atrial appendage thrombosis and embolization is the principal mechanism of stroke in AF. Anticoagulation is underutilized and often contraindicated. METHODS:Thoracoscopic Left Appendage, Tot...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章,多中心研究
doi:10.1016/s0735-1097(03)00953-7
更新日期:2003-10-01 00:00:00
abstract:OBJECTIVES:Our goal was to compare histologically the mechanisms producing congenital complete heart block in normally structured hearts and in hearts with isomerism of the atrial appendages. BACKGROUND:It is known that several different histologic patterns can underscore the existence of congenital complete heart blo...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章
doi:10.1016/0735-1097(92)90191-o
更新日期:1992-10-01 00:00:00
abstract:OBJECTIVES:The goal of this study was to identify genes upregulated in the heart in human patients with hypertrophic cardiomyopathy (HCM). BACKGROUND:Hypertrophic cardiomyopathy is a genetic disease caused by mutations in contractile sarcomeric proteins. The molecular basis of diverse clinical and pathologic phenotype...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章
doi:10.1016/s0735-1097(01)01509-1
更新日期:2001-10-01 00:00:00
abstract::Nuclear magnetic resonance (NMR) imaging has been shown to accurately portray cardiac anatomy and function. To investigate the potential of NMR imaging for the assessment of coronary stenosis in patients with chest pain, ultrafast NMR imaging in conjunction with a T1 (longitudinal relaxation time) contrast agent was p...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章
doi:10.1016/0735-1097(91)90754-w
更新日期:1991-10-01 00:00:00
abstract:OBJECTIVES:The aim of this study was to compare the 3-year efficacy and safety of biodegradable polymer with permanent polymer stents and of everolimus-eluting stents (EES) with sirolimus-eluting stents (SES). BACKGROUND:Biodegradable polymer drug-eluting stents (DES) offer potential for enhanced late outcomes in comp...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章,多中心研究,随机对照试验
doi:10.1016/j.jacc.2011.06.027
更新日期:2011-09-20 00:00:00
abstract:BACKGROUND:In patients with resistant hypertension (RH) and obstructive sleep apnea (OSA), the blood pressure response to continuous positive airway pressure (CPAP) treatment is highly variable and could be associated with differential micro-ribonucleic acid (miRNA) profiles. Currently, no available methods exist to id...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章,多中心研究,随机对照试验
doi:10.1016/j.jacc.2015.06.1315
更新日期:2015-09-01 00:00:00
abstract:OBJECTIVES:This study aimed to compare changes in coronary endothelial function, systemic endothelin-1 (ET-1) levels, and vascular remodeling in heart transplant recipients randomized to cyclosporin A (CyA) or tacrolimus (Tac) immunosuppression. BACKGROUND:Functional endothelial abnormalities and intimal thickening ar...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章,随机对照试验
doi:10.1016/j.jacc.2005.10.073
更新日期:2006-04-18 00:00:00
abstract:BACKGROUND:The prevalence of obstructive coronary artery disease (CAD) in symptomatic patients referred for diagnostic testing has declined, warranting optimization of individualized diagnostic strategies. OBJECTIVES:This study sought to present a simple, clinically applicable tool enabling estimation of the likelihoo...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章
doi:10.1016/j.jacc.2020.09.585
更新日期:2020-11-24 00:00:00
abstract:OBJECTIVES:The purpose of the study was to analyze the factors that favor the occurrence of sustained monomorphic ventricular tachycardia in the early phase (< 48 h) of acute myocardial infarction and to establish its prognostic implications. BACKGROUND:Sustained monomorphic ventricular tachycardia early in the course...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章
doi:10.1016/S0735-1097(96)00383-X
更新日期:1996-12-01 00:00:00
abstract:OBJECTIVE:We compared long-term health outcomes associated with beta-adrenergic blocking agents and diltiazem treatment for unstable angina. BACKGROUND:No long-term data have been published comparing these two antianginal treatments in this setting. METHODS:Eligible veterans were discharged from the Veterans Affairs ...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章
doi:10.1016/s0735-1097(98)00408-2
更新日期:1998-11-01 00:00:00
abstract::Viral respiratory infections are risk factors for cardiovascular disease (CVD). Underlying CVD is also associated with an increased risk of complications following viral respiratory infections, including increased morbidity, mortality, and health care utilization. Globally, these phenomena are observed with seasonal i...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章,评审
doi:10.1016/j.jacc.2020.08.028
更新日期:2020-10-13 00:00:00
abstract:OBJECTIVES:The purpose of the present study was to test the potential of colchicine, an agent with potent anti-inflammatory action, to reduce atrial fibrillation (AF) recurrence after pulmonary vein isolation in patients with paroxysmal AF. BACKGROUND:Proinflammatory processes induced by AF ablation therapy have been ...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章,多中心研究,随机对照试验
doi:10.1016/j.jacc.2012.07.031
更新日期:2012-10-30 00:00:00
abstract:OBJECTIVES:The purpose of this study is to demonstrate the technical success of carotid artery stenting in acute extracranial internal carotid artery (ICA) occlusion as well as the benefit in clinical outcome. BACKGROUND:Stroke caused by acute occlusion of the ICA is associated with a significant level of morbidity an...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章
doi:10.1016/j.jacc.2011.08.044
更新日期:2011-11-29 00:00:00
abstract::The effectiveness of an intermittent regimen of transdermal nitroglycerin in chronic stable angina was evaluated in 206 patients using serial treadmill testing. After a placebo stabilization phase, patients were randomized to 4 weeks of double-blind treatment with transdermal nitroglycerin, 10 or 20 cm2 (equivalent to...
journal_title:Journal of the American College of Cardiology
pub_type: 临床试验,杂志文章,多中心研究,随机对照试验
doi:10.1016/0735-1097(89)90216-7
更新日期:1989-03-15 00:00:00
abstract:OBJECTIVES:We compared the safety of different devices by screening for subclinical intracranial embolic events after pulmonary vein isolation with either conventional irrigated radiofrequency (RF) or cryoballoon or multielectrode phased RF pulmonary vein ablation catheter (PVAC). BACKGROUND:New devices specifically d...
journal_title:Journal of the American College of Cardiology
pub_type: 杂志文章,多中心研究
doi:10.1016/j.jacc.2011.04.010
更新日期:2011-08-09 00:00:00