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Right Ventricular Pacing (right + ventricular_pacing)

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Medical Sciences	100%

Selected Abstracts

Short-Term Effects of Right Ventricular Pacing on Cardiorespiratory Function in Patients With a Biventricular Pacemaker

CONGESTIVE HEART FAILURE, Issue 6 2008
Stefan Toggweiler MD
The intention of this study was to evaluate the short-term effect of right ventricular (RV) pacing on cardiorespiratory function in patients with a biventricular pacemaker. A group of 26 patients with a biventricular pacemaker was enrolled in this cross-over, single-blind study. All patients underwent spiroergometry and electrocardiography in RV and biventricular pacing mode. Peak work capacity (102±32 W and 107±34 W for RV and biventricular pacing mode, respectively; P<.01) and peak oxygen consumption (21.4±6.7 mL/min/kg and 22.6±7.0 mL/min/kg for RV and biventricular pacing mode, respectively; P<.01) were significantly lower in the RV pacing mode. Heart rate at rest was significantly higher with active RV pacing. Short-term RV pacing in patients with a biventricular pacemaker resulted in a higher heart rate at rest, a lower peak work capacity, and a lower peak oxygen consumption compared with that in the biventricular pacing mode. [source]

Acute Pulmonary Hypertension Secondary to Right Ventricular Pacing in a Patient With Sinus Node Dysfunction and Severe Ischemic Cardiomyopathy

CONGESTIVE HEART FAILURE, Issue 3 2005
Giancarlo H. Speziani MD
Right ventricular pacing has been associated with worsening symptoms of heart failure in patients with cardiomyopathy. We describe a patient with severe ischemic cardiomyopathy and sinus node dysfunction who developed acute worsening of pulmonary hypertension immediately after right ventricular pacing. [source]

Long-Term Mechanical Consequences of Permanent Right Ventricular Pacing: Effect of Pacing Site

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 10 2010
DARRYL P. LEONG M.B.B.S.
Optimal Right Ventricular Pacing,Introduction: Long-term right ventricular apical (RVA) pacing has been associated with adverse effects on left ventricular systolic function; however, the comparative effects of right ventricular outflow tract (RVOT) pacing are unknown. Our aim was therefore to examine the long-term effects of septal RVOT versus RVA pacing on left ventricular and atrial structure and function. Methods: Fifty-eight patients who were prospectively randomized to long-term pacing either from the right ventricular apex or RVOT septum were studied echocardiographically. Left ventricular (LV) and atrial (LA) volumes were measured. LV 2D strain and tissue velocity images were analyzed to measure 18-segment time-to-peak longitudinal systolic strain and 12-segment time-to-peak systolic tissue velocity. Intra-LV synchrony was assessed by their respective standard deviations. Interventricular mechanical delay was measured as the difference in time-to-onset of systolic flow in the RVOT and LV outflow tract. Septal A' was measured using tissue velocity images. Results: Following 29 ± 10 months pacing, there was a significant difference in LV ejection fraction (P < 0.001), LV end-systolic volume (P = 0.007), and LA volume (P = 0.02) favoring the RVOT-paced group over the RVA-paced patients. RVA-pacing was associated with greater interventricular mechanical dyssynchrony and intra-LV dyssynchrony than RVOT-pacing. Septal A' was adversely affected by intra-LV dyssynchrony (P < 0.05). Conclusions: Long-term RVOT-pacing was associated with superior indices of LV structure and function compared with RVA-pacing, and was associated with less adverse LA remodeling. If pacing cannot be avoided, the RVOT septum may be the preferred site for right ventricular pacing. (J Cardiovasc Electrophysiol, Vol. 21, pp. 1120-1126) [source]

Severe Atrioventricular Decoupling, Uncoupling, and Ventriculoatrial Coupling During Enhanced Atrial Pacing: Incidence, Mechanisms, and Implications for Minimizing Right Ventricular Pacing in ICD Patients

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 11 2008
MICHAEL O. SWEENEY M.D.
Background: Enhanced AAI/R pacing minimizes right ventricular pacing but may permit or induce AV decoupling (AV-DC) due to unrestricted AV intervals (AVIs). The purpose of this study was to characterize and quantify AVI behavior in a randomized trial of enhanced AAI/R pacing in ICD patients. Methods: One hundred twenty-one patients in the Marquis ICD MVPÔ Study, a randomized 1-month crossover comparison of cumulative% ventricular pacing (Cum%VP) in enhanced AAIR (MVP) vs DDD/R, were analyzed. AV-DC was defined as ,40% AVIs >300 ms; VA coupling (VA-C) was defined as%V-atrial pace (AP) intervals <300 ms. Dynamic AVI behavior and increases in Cum%VP due to AV block (AV uncoupling, AV-UC) were characterized using Holters with real-time ICD telemetry. Results: AV-DC occurred in 17 (14%) of patients. Baseline PR, amiodarone, nighttime, lower rate >60 beats/min, rate response, and Cum%AP were associated with longer AVIs. Logistic regression identified baseline PR (odds ratio [OR]= 1.024, 95% confidence interval [CI] 1.007,1.042; P = 0.005), and Cum%AP (OR = 1.089, 95% CI 1.027,1.154; P = 0.004) as predictors of AV-DC. AV-DC was associated with ,10-fold increases in both Cum%VP (13.6 ± 28.3% vs 1.2 ± 3.9%; P = 0.023) due to transient AV-UC) and VA-C (6.0 ± 17.5% vs 0.5 ± 1.2%, P = 0.028). AV coupling (<40% AVIs >300 ms) was preserved in 104 (86%) patients. Conclusions: AV-DC, VA-C, and AV-UC may be worsened or induced by enhanced AAI/R pacing. Conservative programming of lower rate and rate response should reduce the risk of AV-DC by reducing Cum%AP. [source]

Biventricular Versus Right Ventricular Pacing in Patients with AV Block (BLOCK HF): Clinical Study Design and Rationale

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 9 2007
ANNE B. CURTIS M.D.
Background: Right ventricular (RV) pacing restores ventricular systole in patients with atrioventricular (AV) block, yet recent studies have suggested that in patients with AV block and left ventricular (LV) dysfunction, RV pacing may exacerbate the progression to heart failure (HF). BLOCK HF is a prospective, multi-center, randomized, double-blind, controlled trial designed to determine whether patients with AV block, LV dysfunction (EF , 50%), and mild to moderate HF (NYHA I-III) who require pacing benefit from biventricular (BiV) pacing, compared with RV pacing alone. Objective: The primary objective of this trial is to determine whether the time to first event (all-cause mortality, heart failure-related urgent care, or a , 15% increase in left ventricular end systolic volume index [LVESVI]) for patients with BiV pacing is superior to that of patients with RV pacing. Methods: Patients with AV block and LV dysfunction who require permanent pacing and undergo successful implantation of a commercial Medtronic CRT device, with or without an ICD, will be randomized to BiV or RV pacing. Patients are followed at least every 6 months until study closure. Up to 1,636 patients may be enrolled in 150 centers worldwide. Conclusion: BLOCK HF is a large, randomized, clinical study in pacing-indicated patients with AV block, mild to moderate HF symptoms, and LV dysfunction to determine whether BiV pacing is superior to RV pacing in slowing the progression of HF. [source]

The Clinical Implications of Cumulative Right Ventricular Pacing in the Multicenter Automatic Defibrillator Trial II

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 4 2005
JONATHAN S. STEINBERG M.D.
Introduction: This study was designed to assess whether right ventricular pacing in the implantable cardioverter defibrillator (ICD) arm of the Multicenter Automatic Defibrillator Implantation Trial (MADIT) II was associated with an unfavorable outcome. Methods and Results: Data on the number of ventricular paced beats were available in 567 (76%) of 742 MADIT II patients with ICDs. The number of ventricular paced beats over the total number of beats showed a bimodal distribution with patients being predominantly paced or nonpaced. Therefore, patients were dichotomized at 0,50% and 51,100% of cumulative pacing with median pacing rate 0.2% and 95.6%, respectively. Endpoints included new or worsening heart failure, appropriate ICD therapy for VT/VF, and the combined endpoint of heart failure or death. Clinical features associated with frequent ventricular pacing included age ,65 years, advanced NYHA heart failure class, LVEF < 0.25, first degree AV and bundle branch block, and amiodarone use. During follow-up, 119 patients (21%) had new or worsened heart failure, 130 (23%) had new or worsened heart failure or death, and 142 (25%) had appropriate therapy for VT/VF. In comparison to patients with infrequent pacing, those with frequent pacing had significantly higher risk of new or worsened heart failure (hazard ratio = 1.93; P = 0.002) and VT/VF requiring ICD therapy (HR = 1.50; P = 0.02). Conclusions: Patients in MADIT II who were predominantly paced had a higher rate of new or worsened heart failure and were more likely to receive therapy for VT/VF. These results suggest the deleterious consequences of RV pacing, particularly in the setting of severe LV dysfunction. [source]

Impact of Temporary Interruption of Right Ventricular Pacing for Heart Block on Left Ventricular Function and Dyssynchrony

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1 2010
WEN-JING HONG M.D.
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 ± 7.4 years with congenital heart block (group I) and six patients aged 22.7 ± 11.0 years with surgically acquired heart block (group II) with RV pacing were studied. The pacing rate was reduced to less than patient's intrinsic heart rate and maintained for 5 minutes. The LV ejection fraction (EF), three-dimensional systolic dyssynchrony index (SDI), two-dimensional global longitudinal strain and strain rate, and Doppler-derived isovolumic acceleration before and after interruption of RV pacing were compared. Results:The LVEF and GLS increased while QRS duration decreased after the pacing interruption in both the groups (all P < 0.05). While SDI decreased in both groups I (6.8 ± 2.3%, 3.8 ± 0.8%, P = 0.001) and II (9.2 ± 4.1%,5.0 ± 1.6%, P = 0.032), it remained higher in group II than in group I (P = 0.046) after the pacing interruption. The prevalence of LV dyssynchrony (SDI > 4.7%) decreased in group I (83%,25%, P = 0.006) but not in group II (67%,50%, P = 0.50). The %increase in LVEF correlated positively with %reduction of LV SDI (r = 0.80, P = 0.001). Conclusions:Temporary interruption of chronic RV pacing acutely improves LV dyssynchrony and systolic function in children and young adults, the magnitude of which is greater in patients with congenital than those with surgically acquired heart block. (PACE 2010; 41,48) [source]

New or Aggravated Heart Failure during Long-Term Right Ventricular Pacing after AV Junctional Catheter Ablation

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2 2009
DRITAN POÇI M.D.
Background: Atrioventricular junctional ablation (AVJA) improves symptoms and quality of life in patients with pharmacologically resistant atrial fibrillation (AF). However, long-term right ventricular stimulation has also been reported to lead to deterioration of the left ventricular function. We retrospectively analyzed the incidence of new or aggravated heart failure (HF) during long-term right ventricular stimulation following AVJA. Methods: Two hundred thirteen patients (110F:103M), 73 ± 10 years old, were followed for a period of 6 ± 3 years after AVJA. Forty-nine patients (23%) were known to have HF before AVJA. New HF was diagnosed if at least two of the following criteria were present: NYHA class >2, an LVEF <45%, and medication for HF. Aggravated HF was defined as an increase in the functional class and/or new prescription of medication for HF. All-cause death was a secondary endpoint. Results: During follow-up, 26% of the patients with known HF showed an aggravation of HF, while 13% developed new symptoms of HF. High age and low EF were independent predictors of new or aggravated HF and of new HF, while none of the tested variables predicted aggravation of known HF. The all-cause mortality was 16%, where high age and coronary artery disease were found to be independent predictors. Conclusion: AVJA followed by right ventricular pacing was associated with aggravated HF in 23% of patients with known HF, while development of new symptoms of HF occurred much less often during follow-up (13%). The majority of patients who underwent AVJA continued to do well during long-term follow-up. [source]

Analysis of the Electrocardiographic Waveforms Produced by Right Ventricular Pacing: Relation to the Nonpaced Patterns

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 5 2008
HOWARD S. FRIEDMAN M.D.
Background: Ventricular aberrant conduction has a confounding effect on the known relationships between the electrocardiogram (ECG) and left ventricular (LV) mass. By relating the ECG of right ventricular pacing to LV mass and to nonpaced recordings, clarification of these effects might emerge. Methods and Results: In 30 patients (age, 81 ± 7 years; 13 women) who had right ventricular paced ECGs and echocardiograms, 24 of who also had nonpaced ECGs, comparative analyses were performed. Although the nonpaced ECGs had strong correlations with various echocardiographic measurements, for paced ECGs, only QRS complex voltage and interventricular septal thickness (IVS) were significantly related. However, paced QRS complex voltage relationships correlated with those of nonpaced QRS complexes, ranging from an r = 0.54, P < 0.006, for the sum of the R in aVL and the S in V-3 to r = 0.78, P < 0.001, for the sum of the R in I and the S in III. Paced ECGs had a QRS complex with a greater spatial amplitude, a longer duration, and a more superior position, and had more deeply inverted T waves than nonpaced ECGs. The differences between the voltages of paced and nonpaced QRS complexes, moreover, diminished as LV mass and/or IVS increased. When compared with nonpaced ECGs, paced ECGs showed the most similarity to nonpaced ECGs having a left bundle branch block (LBBB) pattern. Except for the presence of more superiorly directed QRS complexes, paced impulses were not significantly different (P < 0.008) from nonpaced impulses having a LBBB pattern. Also, the nonpaced ECG pattern had no discernable effect on ECG produced by right ventricular (RV) pacing. Conclusions: Despite having weak relations with echocardiographic measurements, the QRS complex voltage of the paced ECG correlated with those of nonpaced ECGs, and the voltage differences between them were smaller as LV mass increased. [source]

Acute Pulmonary Hypertension Secondary to Right Ventricular Pacing in a Patient With Sinus Node Dysfunction and Severe Ischemic Cardiomyopathy

Severe Atrioventricular Decoupling, Uncoupling, and Ventriculoatrial Coupling During Enhanced Atrial Pacing: Incidence, Mechanisms, and Implications for Minimizing Right Ventricular Pacing in ICD Patients

Newly Detected Atrial Fibrillation Following Dual Chamber Pacemaker Implantation

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 12 2006
JIM W. CHEUNG M.D.
Introduction: Pacemaker (PPM)-detected atrial high-rate episodes (AHREs) of even 5-minute duration may identify patients at increased risk for stroke and death. In this study, we sought to determine the incidence of newly detected atrial fibrillation (AF defined as an AHRE ,5 minutes) in patients following dual-chamber PPM implantation and to define the clinical predictors of developing AF. Methods and Results: We evaluated 262 patients (142 male; age 74 ± 12 years) without documented AF who underwent PPM implantation for sinus node dysfunction (n = 122) or atrioventricular block (n = 140). Information regarding patient demographics, cardiovascular diseases, and medication history was obtained. The cumulative percentages of ventricular pacing as well as the frequency, duration, and time to first episode of an AHRE were also determined. During follow-up of 596 ± 344 days, an AHRE ,5 minutes was detected in 77 (29%) patients. Of these, 47 (61%) patients had an AHRE ,1 hour, 22 (29%) patients had an AHRE ,1 day, and 12 (16%) patients had an AHRE ,1 week. An AHRE ,5 minutes was seen in 24% and 34% of patients at 1 year and 2 years, respectively. Among patients with sinus node dysfunction, ,50% cumulative ventricular pacing was the only significant predictor of an AHRE ,5 minutes (HR 2.2; CI 1.0,4.7; P = 0.04). Conclusions: Within 1 year of PPM implantation, AF is detected in 24% of patients without history of AF. In patients with sinus node dysfunction, ,50% cumulative right ventricular pacing is associated with a 2-fold increase in risk of developing AF. [source]

Multicenter, Prospective, Randomized Safety and Efficacy Study of a New Atrial-Based Managed Ventricular Pacing Mode (MVP) in Dual Chamber ICDs

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 8 2005
MICHAEL O. SWEENEY M.D.
Background: Ventricular desynchronization caused by right ventricular pacing may impair ventricular function and increase risk of heart failure (CHF), atrial fibrillation (AF), and death. Conventional DDD/R mode often results in high cumulative percentage ventricular pacing (Cum%VP). We hypothesized that a new managed ventricular pacing mode (MVP) would safely provide AAI/R pacing with ventricular monitoring and DDD/R during AV block (AVB) and reduce Cum%VP compared to DDD/R. Methods: MVP RAMware was downloaded in 181 patients with Marquis DR ICDs. Patients were initially randomized to either MVP or DDD/R for 1 month, then crossed over to the opposite mode for 1 month. ICD diagnostics were analyzed for cumulative percentage atrial pacing (Cum%AP), Cum%VP, and duration of DDD/R pacing for spontaneous AVB. Results: Baseline characteristics included age 66 ± 12 years, EF 36 ± 14%, and NYHA Class II,III 36%. Baseline PR interval was 190 ± 53 msec and programmed AV intervals (DDD/R) were 216 ± 50 (paced)/189 ± 53 (sensed) msec. Mean Cum%VP was significantly lower in MVP versus DDD/R (4.1 ± 16.3 vs 73.8 ± 32.5, P < 0.0001). The median absolute and relative reductions in Cum%VP during MVP were 85.0 and 99.9, respectively. Mean Cum%AP was not different between MVP versus DDD/R (48.7 ± 38.5 vs 47.3 ± 38.4, P = 0.83). During MVP overall time spent in AAI/R was 89.6% (intrinsic conduction), DDD/R 6.7% (intermittent AVB), and DDI/R 3.7% (AF). No adverse events were attributed to MVP. Conclusions: MVP safely achieves functional atrial pacing by limiting ventricular pacing to periods of intermittent AVB and AF in ICD patients, significantly reducing Cum%VP compared to DDD/R. MVP is a universal pacing mode that adapts to AVB and AF, providing both atrial pacing and ventricular pacing support when needed. [source]

The Clinical Implications of Cumulative Right Ventricular Pacing in the Multicenter Automatic Defibrillator Trial II

Rationale and Design of the OPTION Study: Optimal Antitachycardia Therapy in ICD Patients without Pacing Indications

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 9 2010
CHRISTOF KOLB M.D.
Background:,Implantable cardioverter-defibrillators (ICDs) represent the treatment of choice for primary and secondary prevention of sudden cardiac death but ICD therapy is also plagued by inappropriate shocks due to supraventricular tachyarrhythmias. Dual-chamber (DC) ICDs are considered to exhibit an enhanced discrimination performance in comparison to single-chamber (SC) ICDs, which results in reduction of inappropriate detections in a short- to mid-term follow-up. Comparative data on long-term follow-up and especially on inappropriate shocks are limited. Methods:,The aim of the OPTION study is to assess whether an optimized treatment with DC ICDs improves patient outcome and decreases the rate of inappropriate shocks in comparison to SC ICDs. DC ICD therapy optimization is achieved by optimal customizing of antitachycardia therapy parameters, activation of discrimination algorithms, antitachycardia pacing in the slow ventricular tachycardia zone, and avoidance of right ventricular pacing with the SafeR algorithm mode. The OPTION study, a prospective, multicenter, randomized, single-blinded, parallel study, will randomize 450 patients on a 1:1 allocation to either an SC arm with backup pacing at VVI 40 beats per minute (bpm) or to the DC arm with SafeR pacing at 60 bpm. Patients will be followed for 27 months. Primary outcome measure is the time to first occurrence of inappropriate shock and a combined endpoint of cardiovascular morbidity and all-cause mortality. Conclusion:,The study will evaluate the relative performance of DC in comparison to SC ICDs in terms of inappropriate shock reduction and patient outcome. (PACE 2010; 33:1141,1148) [source]

New or Aggravated Heart Failure during Long-Term Right Ventricular Pacing after AV Junctional Catheter Ablation

Analysis of the Electrocardiographic Waveforms Produced by Right Ventricular Pacing: Relation to the Nonpaced Patterns

Optimization of Repolarization during Biventricular Pacing: A New Target in Patients with Biventricular Devices?

ANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 1 2010
Cengizhan Türko, lu M.D.
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 with nonischemic and five with ischemic cardiomyopathy due to anterior myocardial infarction were enrolled. No correlation was observed between values of repolarization among patients. The optimal values of repolarization were significantly different from values of echocardiographically guided hemodynamic optimization. Two patients with biventricular pacing-induced ventricular fibrillation were successfully treated by reprogramming of V-V delay according to interventricular delay resulting in shorter Tpeak-Tend interval, although delayed effect of amiodarone in one of these patients cannot be ruled out. Conclusions: Patients with biventricular devices may be prone to development of ventricular arrhythmias depending on programmed V-V interval. We suggest that optimization of repolarization may be performed in patients with biventricular pacemakers in the absence of backup ICD and those with frequent episodes of ventricular tachyarrhythmias, although this finding deserves further study. Ann Noninvasive Electrocardiol 2010;15(1):36,42 [source]