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Mehta Chetan - - 2010
Infants and children with congenital aortic stenosis and coarctation of the aorta can be treated by catheter intervention. There are several pharmacological and mechanical techniques described to overcome the balloon movement; none, however, have proved entirely satisfactory. An alternative method to achieve balloon stability is the use of rapid ventricular ...
Orlov Michael V - - 2010
BACKGROUND: Randomized trials have demonstrated benefits of biventricular (BiV) pacing in patients with advanced heart failure, intraventricular conduction delay, and atrial fibrillation (AF) post-atrioventricular (AV) node ablation. The AV Node Ablation with CLS and CRT Pacing Therapies for Treatment of AF trial (AVAIL CLS/CRT) was designed to demonstrate superiority of ...
Romero Daniel - - 2010
Heart failure leads to gross cardiac structural changes. While cardiac resynchronization therapy (CRT) is a recognized treatment for restoring synchronous activation, it is not clear how changes in cardiac shape and size affect the electrical pacing therapy. This study used a human heart computer model which incorporated anatomical structures such ...
Liu Enzhao - - 2010
Renin-angiotensin system (RAS) is activated in the fibrillating atria. Angiotensin-(1-7) [Ang-(1-7)] counterbalances the actions of angiotensin II (Ang II). To investigate the effects of Ang-(1-7) on the long-term atrial tachycardia-induced atrial fibrosis and atrial fibrillation (AF) vulnerability, eighteen dogs were assigned to sham group, paced group, or paced+Ang-(1-7) group, 6 ...
Mehta Chetan - - 2010
Introduction: Infants and children with congenital aortic stenosis and coarctation of the aorta can be treated by catheter intervention. There are several pharmacological and mechanical techniques described to overcome the balloon movement; none, however, have proved entirely satisfactory. An alternative method to achieve balloon stability is the use of rapid ...
La Rocca Vincenzo - - 2010
OBJECTIVES: Little is known about coronary sinus lead performance in patients with cardiac resynchronization therapy devices. We evaluated the impact of clinical and technical parameters on coronary sinus lead performance over long-term follow-up. METHODS: From February 1999 to July 2004, 235 patients (181 men; mean age, 68 +/- 9 years; ...
Watanabe Ichiro - - 2010
Sustained atrial fibrillation (AF) was induced by atrial burst pacing, and monophasic action potentials (MAPs) were recorded. MAP alternans was observed at a cycle length (CL) of 167.5 ± 28.2 msec before burst pacing and 201.3 ± 40.2 msec after burst pacing. AF > 5 minutes duration was induced in ...
Murakami Yoshimasa - - 2010
AIMS: Managed ventricular pacing (MVP) and Search AV+ are representative dual-chamber pacing algorithms for minimizing ventricular pacing (VP). This randomized, crossover study aimed to examine the difference in ability to reduce percentage of VP (%VP) between these two algorithms. METHODS AND RESULTS: Symptomatic bradyarrhythmia patients implanted with a pacemaker equipped ...
T?rko?lu Cengizhan - - 2010
BACKGROUND: Evaluation of repolarization during sequentional biventricular pacing. METHODS: Patients with biventricular devices, and left ventricular leads placed to the basal part of lateral left ventricular wall were enrolled. QRS, QTc, JTc, and corrected Tpeak-Tend intervals were compared during sequentional biventricular, left ventricular, and right ventricular pacing. RESULTS: Five patients ...
Van Casteren Lieve - - 2010
Cardiac resynchronization permits atrial-synchronized simultaneous pacing of both left and right ventricles in order to optimize mechanical contraction. In case of an atrial tachycardia, a VVI-'ventricular sense'-tracking modus can be programmed to maintain biventricular pacing. In this case report, we describe the use of this modus.
Edner Magnus - - 2010
Biventricular pacing (BiP) is an effective treatment in systolic heart failure (HF) patients with prolonged QRS. However, approximately 35% of the patients receiving BiP are classified as non-responders. The aim of this study is to evaluate the acute effects of VV-optimization on systolic heart function. Twenty-one HF patients aged 72 ...
Deneke Thomas - - 2010
Biventricular (BiV) is extensively used in the treatment of congestive heart failure but so far no recommendations for optimized programming of atrioventricular-delay (AVD) settings have been proposed. Can AVD optimization be performed using a simple formula based on non-invasive doppler-echocardiography? 25 patients (ejection fraction 30+/-8%) received BiV ICDs. Doppler-echocardiographic evaluation ...
Saba Samir - - 2010
Biventricular (BIV) pacing can improve cardiac function in heart failure by altering the mechanical and electric substrates. We investigated the effect of BIV versus right ventricular (RV) pacing on the normal heart. Male New Zealand White rabbits (n=33) were divided into 3 groups: sham-operated (control), RV pacing, and BIV pacing ...
ten Cate Tim J F - - 2010
BACKGROUND: The value of myocardial perfusion SPECT (MPS) for patients with left bundle branch block (LBBB) or right ventricular apical (RVA) pacing seems reduced. The prognosis of patients with only abnormal activation related perfusion defects (AARD) due to LBBB or RVA-pacing is similar to those with a normal MPS. We ...
Pastore Gianni - - 2010
BACKGROUND: The right ventricular septum (RVS) and Hisian area (HA) are considered more "physiological" pacing sites than right ventricular apex (RVA). Studies comparing RVS to RVA sites have produced controversial results. There are no data about variability of electromechanical activation obtained by an approach using fluoroscopy and electrophysiological markers. This ...
Pan Wenzhi - - 2010
BACKGROUND: The value between paced QRS duration (pQRSd) and native QRS duration (nQRSd) in paced population has not been compared. The relation between nQRSd and pQRSd remains undefined now. METHODS AND RESULTS: A total of 310 right ventricular apex (RVA) paced patients were enrolled. The correlation coefficients between nQRSd and ...
Ouali Sana - - 2010
BACKGROUND: Dual-chamber pacing is believed to have an advantage over single-chamber ventricular pacing. The aim of the study was to determine whether elderly patients with implanted pacemaker for complete atrioventricular block gain significant benefit from dual-chamber (DDD) compared with single-chamber ventricular demand (VVIR). METHODS: The study was designed as a ...
van Geldorp Irene E - - 2010
AIMS: To investigate whether cardiac resynchronization therapy (CRT) by means of biventricular (BiV) pacing can improve left ventricular (LV) function, remodelling and clinical status in chronically right ventricular (RV) paced patients with mild cardiomyopathy. METHODS AND RESULTS: Thirty-six chronically (10 +/- 7 years) RV paced patients with left ventricular ejection ...
Inoue Katsuji - - 2010
OBJECTIVE: The study objective was to compare the left ventricular (LV) dyssynchrony and torsional behavior between right ventricular apical (RVA) and right ventricular septal (RVS) pacing. METHODS: Forty-six patients with symptomatic sick sinus syndrome and preserved LV function were assigned to 2 groups: RVA (n = 23) and RVS (n ...
Henz Benhur D - - 2009
BACKGROUND: Right ventricular apical (RVA) pacing promotes tricuspid regurgitation (TR), electromechanical dyssynchrony, and ventricular dysfunction. We tested a novel intramyocardial bipolar lead to assess whether stimulation of the atrioventricular septum (AVS) produces synchronous ventricular activation without crossing the tricuspid valve (TV). METHODS: A lead with an active external helix and ...
Skadsberg Nicholas D - - 2009
OBJECTIVE: Right ventricular (RV) pacing has been associated with abnormal cardiac electrical and mechanical dyssynchrony, resulting in impaired global and regional ventricular pump function. This study aimed to characterize the relative effects of pacing site on left ventricular (LV) activation patterns and associated hemodynamic performances. METHODS: Acute pacing was performed ...
Ukkonen Heikki - - 2009
Right ventricular (RV) apical pacing induces dyssynchrony by a left bundle branch block type electrical activation sequence in the heart and may impair left ventricular (LV) function. Whether these functional changes are accompanied by changes in myocardial perfusion, oxidative metabolism and efficiency, and the relation with the induction of LV ...
Devecchi Paolo - - 2009
BACKGROUND: In healthy people the left ventricle presents a counter-clockwise apical rotation and a clockwise basal rotation ending in late systole. In early systole (during isovolumic contraction) there is a fast and inverse rotation (counter-clockwise at the base and clockwise at the apex). This opposite rotation between apex and base ...
Gong Xue - - 2009
BACKGROUND: Whether right ventricular outflow tract (RVOT) pacing is superior to right ventricular apex (RVA) pacing in terms of ventricular synchrony, cardiac function, and remodeling in patients with normal cardiac function is still unknown. HYPOTHESIS: Right ventricular outflow tract pacing is superior to RVA pacing in patients with normal cardiac ...
Day Geoffrey A - - 2009
BACKGROUND: A properly placed stimulus on the T-wave during ventricular repolarization can result in ventricular fibrillation (VF). Initiation of VF with pacing on T-wave is a rare event with a few reported cases in the literature. We present a unique case of induced VF attributed to a pacing stimulus on ...
Heinroth Konstantin M - - 2009
BACKGROUND: Transcoronary pacing for the treatment of bradycardia during percutaneous coronary intervention (PCI) is not well established, but may be a useful technique in interventional cardiology. We developed a porcine model to examine the feasibility and efficacy of transcoronary pacing during PCI. METHODS AND RESULTS: Eight pigs under general anesthesia ...
M?llmann H - - 2009
BACKGROUND: Previous large animal heart failure models led to inhomogeneous results. Therefore, we developed a novel model combining rapid pacing with forced ventricular desynchronization. METHODS: Heart failure was induced in 20 pigs during a pacing period of 21 days. Group A (n = 10) received one right ventricular lead (220 ...
Fang Fang - - 2010
Right ventricular apical (RVA) pacing may induce mechanical dyssynchrony. However, its impact on patients with normal ejection fraction (EF) is not fully understood. This study examined the prevalence and predictors of RVA pacing-induced systolic dyssynchrony by real-time three-dimensional echocardiography (RT3DE), and evaluated its impact on left ventricular (LV) function. Ninety-three ...
Derval Nicolas - - 2010
OBJECTIVES: We sought to evaluate the impact of the left ventricular (LV) pacing site on hemodynamic response to cardiac resynchronization therapy (CRT). BACKGROUND: CRT reduces morbidity and mortality in heart failure patients. However, 20% to 40% of eligible patients may not fully benefit from CRT device implantation. We hypothesized that ...
Yu Cheuk-Man - - 2009
BACKGROUND: Observational studies suggest that conventional right ventricular apical pacing may have a deleterious effect on left ventricular function. In this study, we examined whether biventricular pacing is superior to right ventricular apical pacing in preventing deterioration of left ventricular systolic function and cardiac remodeling in patients with bradycardia and ...
Lim Sern - - 2010
The ventricular sense response (VSR) algorithm enforces biventricular pacing on ventricular sensing to maximize biventricular pacing in patients with atrial fibrillation. This report describes a case of recurrent ventricular tachycardia that may be facilitated by this enforced pacing algorithm.
Ro Pamela S - - 2009
Pediatric patients with complete heart block (CHB) often require pacemaker therapy. Adult studies have shown chronic right ventricular pacemaker therapy may be associated with decreased echocardiographic parameters and increased brain natriuretic peptide (BNP) values. The goal of this study was to determine if there are echocardiographic or BNP changes in ...
Simantirakis Emmanuel N - - 2009
Right ventricular apical (RVA) stimulation, although beneficial in the treatment of symptomatic bradycardia, has proven detrimental in a substantial percentage of pacemaker recipients, leading to iatrogenic deterioration of left ventricular structure and function. Alternative right ventricular pacing sites appeared advantageous but their superiority has not been proven. Biventricular stimulation is ...
Leclercq Christophe - - 2009
Biventricular pacing is an efficient treatment to improve symptoms and clinical outcome in patients with drug-refractory heart failure, low left ventricular ejection fraction and wide QRS. The basis of the treatment is the permanent delivery of biventricular pacing. During the follow-up of biventricular devices the assessment of permanent biventricular capture ...
del Romeral Luisa Muñoz - - 2009
The pacing site has been shown to influence functional improvement with cardiac resynchronization therapy. We evaluated the effects of the pacing site on left ventricular (LV) function in an animal model. Equilibrium radionuclide angiography was acquired in sinus rhythm (NSR) and with ventricular pacing, from three pacing sites in seven ...
Wang Yu-Chen - - 2009
AIMS: The immediate effects of electric remodelling on the left ventricular (LV) function by dual-chamber pacemakers remain unknown. The purpose of our study was to assess the interaction between heart rates and right ventricular pacing (VP) on LV contractility and diastolic function. METHOD AND RESULTS: Twenty-five patients with dual-chamber pacemakers ...
Estrada Amara H - - 2009
OBJECTIVE: To compare left ventricular synchronization and systolic performance with transvenous pacing of the right ventricular apex (RVA), left ventricular free wall (LVF) or simultaneous pacing of the RVA and LVF (BiV). ANIMALS, MATERIALS AND METHODS: Seven canine patients with complete heart block. Prospective study evaluating effect of pacing site. ...
Quinn T Alexander - - 2009
The goal of this work was to investigate the hemodynamic effects of simultaneous left ventricular (LV) pacing site (LVPS) and interventricular pacing delay (VVD) variation with biventricular pacing (BiVP) during acute LV failure. Simultaneously varying LVPS and VVD with BiVP has been shown to improve hemodynamics during acute right ventricular ...
Lumens Joost - - 2009
In pulmonary arterial hypertension (PAH), duration of myofiber shortening is prolonged in the right ventricular (RV) free wall (RVfw) compared with that in the interventricular septum and left ventricular free wall. This interventricular mechanical asynchrony eventually leads to right heart failure. We investigated by computer simulation whether, in PAH, early ...
Rosso Raphael - - 2010
BACKGROUND: The detrimental effects of right ventricular (RV) apical pacing on left ventricular function has driven interest in alternative pacing sites and in particular the mid RV septum and RV outflow tract (RVOT). RV septal lead positioning can be successfully achieved with a specifically shaped stylet and confirmed by the ...
Hong Wen-Jing - - 2010
BACKGROUND: The increasing data suggest an association between chronic right ventricular (RV) and left ventricular (LV) dysfunction. We sought to determine the effect of temporary interruption of long-term RV pacing on LV function and mechanical dyssynchrony in children and young adults with complete heart block. METHODS: Twelve patients aged 20.0 ...
Scott Paul A - - 2009
Inadvertent placement of a pacemaker lead in the left ventricle (LV) is a rare complication of pacing. We describe a case of inadvertent LV pacing where the ventricular lead traversed the mediastinum and accessed the heart through the posterior wall of the left atrium. Both transesophageal echo and venography were ...
Yamada Takumi - - 2010
A 65-year-old man with frequent premature ventricular contractions (PVCs) underwent electrophysiological testing. Although an excellent pace map was obtained from the right coronary cusp (RCC), radiofrequency ablation at that site interrupted the PVCs transiently. Successful ablation was achieved in the left coronary cusp with earlier local ventricular activation during the ...
Hsieh Yu-Cheng - - 2009
BACKGROUND: Therapeutic hypothermia (TH, 30 degrees C) protects the brain from hypoxic injury. However, TH may potentiate the occurrence of lethal ventricular fibrillation (VF), although the mechanism remains unclear. The present study explored the hypothesis that TH enhances wavebreaks during VF and S(1) pacing, facilitates pacing-induced spatially discordant alternans (SDA), ...
Nguyen Charles T - - 2010
For infants with congenital complete atrioventricular block (CCAVB), the choice of pacing modalities is limited. Due to their size and surgical limitations, neonates typically start with an epicardial right ventricular pacing system, then upgrade to right-sided dual-chamber pacing once appropriate size is achieved. These modes are generally well tolerated. However, ...
Anderson Sara E - - 2010
We describe effects of pacing lead position and cardiac microanatomy on electrical pacing parameters. Passive fixation transvenous pacing leads were implanted in anterior interventricular veins in isolated swine hearts (n = 6). Electrical pacing parameters were measured in 3 implant positions (5 implant sites each): touching myocardial side of venous ...
Fishberger Steven B - - 2009
We report the technique of transatrial delivery of the Medtronic 3830 SelectSecure lead (Medtronic Inc., Minneapolis, MN, USA) for right ventricular endocardial pacing in two young adults with congenital heart disease who had multiple pacing lead failures and superior vena cava occlusion. The deflectable catheter delivery system used to position ...
Albouaini K - - 2009
The right ventricular apex (RVA) has been the elective site for placing endocardial pacing leads since 1959 when Furman described the use of the transvenous route for pacemaker implantation. This site was used because it is easily accessible, readily identified and associated with a stable position and reliable chronic pacing ...
Maraschiello Mark A - - 2009
AIM: The study aimed to determine if right ventricular apical pacing is associated with adverse change in atrial substrate compared with right ventricular septal pacing. METHODS: Patients with septal leads and dual-chamber devices with more than 3 months of follow-up and 70% or higher cumulative percentage of ventricular pacing were ...
Guiraudon Gerard M - - 2009
: To test an alternative to catheter and open-heart techniques, by documenting the feasibility of implanting an unmodified mechanical aortic valve (AoV) in the off pump, beating heart using the universal cardiac introducer (UCI) attached to the left ventricular (LV) apex. : In six pigs, the LV apex was exposed ...
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