			Home About us Contact

Pacemaker Implantation (pacemaker + implantation)

Distribution by Scientific Domains

Medical Sciences	100%

Distribution within Medical Sciences

Cardiovascular Disease	89%
General & Introductory Veterinary Medicine	2%
2 Other Subdomains	9%

Kinds of Pacemaker Implantation

permanent pacemaker implantation

Selected Abstracts

Real-Time Three-Dimensional Echocardiography in Diagnosis of Right Ventricular Pseudoaneurysm after Pacemaker Implantation

ECHOCARDIOGRAPHY, Issue 3 2006
Xuedong Shen M.D.
Right ventricular rupture is a critical cardiac complication associated with cardiac tamponade and death. Occasionally, the site of rupture may be contained by the parietal pericardium and thrombus, thus forming a pseudoaneurysm. Cases of traumatic pseudoaneurysm of the right ventricle have been reported. However, right ventricular pseudoaneurysm following pacemaker implantation has not been previously reported. This case demonstrates two right ventricular pseudoaneurysms following perforation of the right ventricular wall using real-time three-dimensional echocardiography (3DE) after pacemaker implantation although only one definite pseudoaneurysm was diagnosed by routine two-dimensional echocardiography (2DE). We also found that color Doppler 3DE enhanced visualization of the connections between the right ventricle and the pseudoaneurysm. Color Doppler 3DE allowed us to peel away the myocardial tissue and rotate the image to study the jets from different angles. In summary, real-time 3DE and color Doppler 3DE provided excellent visualization of the right ventricular pseudoaneurysm, flow between the ventricle and the pseudoaneurysm, and additional information to that obtained by 2DE. [source]

Risk Factors for Requirement of Permanent Pacemaker Implantation After Aortic Valve Replacement

JOURNAL OF CARDIAC SURGERY, Issue 3 2006
Hasan Basri Erdogan M.D.
Methods: Among 465 patients operated between 1994 and 2004, 19(4.1%) patients with a mean age 49.9 ± 17.2 years required the implantation of a permanent pacemaker. Eleven of them were female (57.9%). The main indication was aortic stenosis (89.5%). Severe annular calcification was documented in 78.9% of them, and the aortic valve was bicuspid in 57.9%. Results: Risk factors for permanent pacing after aortic valve replacement (AVR) identified by univariate analysis were female sex, hypertension, preoperative ejection fraction, aortic stenosis, annular calcification, bicuspid aorta, presence of right bundle branch block (RBBB) or left bundle branch block (LBBB), prolonged aortic cross-clamp and perfusion times, and preoperative use of calcium channel blockers. Multivariate analysis showed that female sex (p = 0.01, OR; 5.21, 95% CI: 1.48-18.34), annular calcification (p < 0.001, OR; 0.05, 95% CI: 0.01-0.24), bicuspid aortic valve (p = 0.02, OR; 0.24, 95% CI: 0.07-0.84), presence of RBBB (p = 0.009, OR; 0.03, 95% CI: 0.003-0.44) or LBBB (p = 0.01, OR; 0.13, 95% CI: 0.02-0.69), hypertension (p = 0.03, OR; 0.22, 95%CI: 0.05-0.89), and total perfusion time (p = 0.002, OR; 1.05, 95% CI: 1.01-1.08) were associated risk factors. Conclusion: Irreversible atrioventricular block requiring a permanent pacemaker implantation is an uncommon complication after AVR. Risk factors are annular calcification, bicuspid aorta, female sex, presence of RBBB or LBBB, prolonged total perfusion time, and hypertension. [source]

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]

Predictors of Complete Heart Block After Alcohol Septal Ablation for Hypertrophic Cardiomyopathy and the Timing of Pacemaker Implantation

JOURNAL OF INTERVENTIONAL CARDIOLOGY, Issue 1 2007
F.R.A.C.P., SEIFEDDIN S. EL-JACK M.B.B.S.
Catheter-based alcohol septal ablation has recently been introduced for the treatment of left ventricular outflow tract obstruction in hypertrophic obstructive cardiomyopathy. It is associated with various conduction disturbances and may lead to transient or persistent complete heart block (CHB). Electrocardiographic (ECG) changes and predictors of developing CHB and the timing of permanent pacemaker implantation have been variable among the different studies. Among 50 patients studied, we found that a new right bundle branch pattern was the most common new ECG change after septal ablation and that baseline left bundle branch block was strongly associated with the development of CHB (P = 0.004); 9 patients (18%) required permanent pacemaker implantation of whom 7 (78%) remained pacemaker dependent at 14 days with no delayed recovery of atrioventricular conduction. This favors an early pacemaker implantation strategy. [source]

Severe Venous and Lymphatic Obstruction after Single-Chamber Pacemaker Implantation in a Patient with Chest Radiation Therapy

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 4 2010
JOSHUA M. DIAMOND M.D.
A 73 - year - old woman with a history of paroxysmal atrial fibrillation, sinus node dysfunction, bilateral breast cancer, and extensive chest radiation developed progressive edema, dyspnea, and recurrent pleural effusions soon after single - chamber pacemaker implantation. Thoracentesis yielded a diagnosis of chylothorax, and progressive refractory anasarca developed. A computed tomography angiogram suggested obstruction of the superior vena cava and left subclavian vein despite outpatient therapeutic anticoagulation. Autopsy confirmed venous thrombosis, along with mediastinal fibrosis. The presumed etiology of the chylothorax and anasarca was obstruction of the atretic central venous structures following pacemaker implantation, critically impairing the already tenuous venous and lymphatic drainage. (PACE 2010; 520,524) [source]

Successful Cervical MR Scan in a Patient Several Hours after Pacemaker Implantation

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 10 2009
DORITH GOLDSHER M.D.
Recent data showed that patients with electrical implanted devices may under certain conditions be scanned safely by magnetic resonance imaging (MRI). The device must have been in place preferably for at least 4,8 weeks [Correction added after online publication 31-Aug-2009: number of weeks has been updated.] prior to MR imaging to allow healing and pacemaker pocket formation. We report on a patient with quadriplegia and suspected epidural hematoma referred for MR scan a day after he had a pacemaker implantation. The patient was also pacemaker-dependent. After considering the risk/benefit ratio in this patient, it was decided to perform the scan. The pacemaker was reprogrammed. MRI was performed under strict monitoring. A spinal cord contusion at the level of C1,3 was diagnosed. Based on the imaging findings no invasive procedure was done. Device interrogation found no change in sensing or pacing parameters or in the pacemaker's battery. At the end of the scan, the device was reprogrammed back to the initial settings. In this population, each scan should be discussed thoroughly and the risks to benefit ratio should be considered. Given appropriate precautions, in well-experienced imaging centers, MRI may be safely performed in patients with permanent cardiac electronic implantable devices. [source]

Permanent Pacemaker Implantation Following Cardiac Surgery: Indications and Long-Term Follow-Up

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1 2009
OFER MERIN M.D.
Background: Conduction disturbances requiring permanent pacemaker implantation after heart surgery occur in about 1.5% of patients. Early pacemaker implantation may reduce morbidity and postoperative hospital stay. We reviewed our experience with patients undergoing surgery to try and identify predictors for pacemaker requirements and patients who will remain pacemaker dependent. Methods: We performed a retrospective review of 4,999 patients undergoing surgery between the years 1993 and 2005. Patient age was 64 ± 12 years, and 71% were males. Coronary bypass was performed in 4,071 (81%), aortic valve replacement in 675 (14%), and mitral valve replacement in 968 (18%) patients. Results: Seventy-two patients (1.4%) required implantation of a permanent pacemaker after surgery. Indications for pacemaker implantation included complete atrioventricular block in 59, symptomatic bradycardia/slow atrial fibrillation in nine, second-degree atrioventricular block in two, and other conduction disturbances in two patients. Predictors for pacemaker requirement by multivariate analysis were left bundle branch block and aortic valve replacement (P < 0.001). Late follow-up was available in 58 patients, at 72 ± 32 months. Thirty-seven (63%) were pacemaker dependent. Predictors for late pacemaker dependency were third-degree atrioventricular block after surgery and preoperative left bundle branch block (P < 0.001). Conclusions: Patients at high risk for pacemaker implantation after heart surgery include those with preexisting conduction disturbances, and those undergoing aortic valve replacement. Of those receiving a pacemaker, about one-third will recover at late follow-up. For patients in the high-risk group who are pacemaker dependent after surgery, we recommend implanting a permanent pacemaker at 5 days after surgery, thus enabling early mobilization and early discharge. [source]

Percutaneous Permanent Pacemaker Implantation Via The Azygous Vein In A Patient With Superior Vena Cava Occlusion

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 3 2008
M.R.C.P., RAVINDU HASMUKH KAMDAR B.Sc. (Hons)
Occlusion of the superior vena cava (SVCO) makes implantation of permanent pacemakers challenging and difficult. We describe an extended application of a Medtronic Attain (Medtronic Inc., Minneapolis, MN, USA) guide catheter (a tool designed for delivery of left ventricular pacing leads into the coronary sinus) for delivery of a right ventricular pacing lead via the azygous vein in a 72-year-old woman with SVCO secondary to long-term central venous hemodialysis catheters. This approach allowed the use of an endocardial pacing lead, implantation under local anesthesia, and conventional positioning of the pacemaker generator in the pectoral region in a patient with SVCO. [source]

Inferior Vena Cava Approach to Permanent Pacemaker Implantation

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 6 2007
MARTIN BRUECK M.D.
A 89-year-old woman required permanent pacemaker implantation because of symptomatic bradyarrhythmia with multiple falls and repeated fractures. Because of the obstruction of the thoracic veins and infection of both groins, an alternative approach via directly punctured inferior vena cava was performed. At follow-up, the patient remained well with an excellent symptomatic response to pacing. The method seems simple to perform and is an alternative when the usual pectoral implantation site is inaccessible. [source]

Colonic Perforation Following Intraoperative Temporary Pacemaker Implantation

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 4p1 2003
PARIND M. OZA
OZA, P.M., et al.: Colonic Perforation Following Intraoperative Temporary Pacemaker Implantation. This report describes the case of a 73-year-old man who was referred for consultation for increasing abdominal free air 1 week after he underwent surgery for aortic valve replacement and coronary artery bypass grafting with intraoperative pacemaker implantation. Laparoscopic exploration revealed that the pacemaker wires had passed through the left transverse colon. Although no previous reports of colonic perforation due to pacemaker lead placement was found, this experience suggests that physicians should suspect this complication in patients with increasing free intraabdominal air and peritoneal signs who have recently undergone placement of a temporary cardiac pacing system. (PACE 2003; 26[Pt. I]:918,919) [source]

Determinants of Persistent Atrial Fibrillation in Patients with DDD Pacemaker Implantation

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 3 2003
AHMET DURAN DEMIR
DEMIR, A.D., et al.: Determinants of Persistent Atrial Fibrillation in Patients with DDD Pacemaker Implantation.Occurrence of AF in a pacemaker implanted patient is a significant cause of morbidity and mortality. The aim of this study was to prospectively investigate the clinical, echocardiographic, and electrocardiographic determinants of persistent AF in patients with DDD pacemakers. A 101 consecutive patients were followed for an average of19.8 ± 11.8months. Persistent AF was documented in 21 (20.8%) patients and 80 (79.2%) patients were in sinus or physiologically paced rhythm. In patients with persistent AF, previous AF attacks were observed more frequently(P < 0.03)and left atrial dimension was higher(3.5 ± 0.6vs3.0 ± 0.5 cm, P < 0.001). Average P maximum and P wave dispersion (PWD) values calculated in a 12-lead surface electrocardiogram were also found to be significantly higher in patients with persistent AF(P < 0.001). Cox regression analysis demonstrated that the presence of previous AF attacks(RR 8.95, P < 0.001), increased left atrial dimension(RR 2.1, P < 0.02), P maximum duration120 ms (RR 6.1, P < 0.001), and PWD 40 ms(RR 12.2, P < 0.001)were associated with an increased risk of persistent AF. Cut-off points were 120 ms for P maximum and 40 ms for PWD. Sensitivity, specificity, and positive and negative predictive values were calculated as 76.2, 82.5, 53.3, and 92.9 for P maximum and as 85.7, 87.5, 64.3, and 95.9 for PWD, respectively. In patients with DDD pacemakers, previous AF attacks, increased left atrial dimension, P maximum value of 120 ms, and a PWD value of 40 ms were associated with a significantly increased risk of persistent AF. These patients must further be managed with other treatment modalities to prevent the development of persistent AF. (PACE 2003; 26:719,724) [source]

Delayed Complications Following Pacemaker Implantation

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 8 2002
KENNETH A. ELLENBOGEN
ELLENBOGEN, K.A., et al.: Delayed Complications Following Pacemaker Implantation. Acute complications resulting from permanent pacemaker implantation are well known and include perforation of the right atrium or right ventricle. Recently, several reports have described the occurrence of perforation and pericarditis as late complications following pacemaker implantation. These complications may occur days to weeks following uncomplicated pacemaker implantation and may lead to death if they are not recognized early. Five patients with late complications caused by active-fixation leads are reported and the clinical features of their presentation and management are reviewed. Late perforation of the right atrium or right ventricle is an uncommon complication after pacemaker implantation but should be suspected by the general cardiologist in a patient who has a device implanted within a week to several months prior to the development of chest pain. [source]

Criteria for Pacemaker Explant in Patients Without a Precise Indication for Pacemaker Implantation

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 3 2002
MARTINO MARTINELLI
MARTINELLI, M., et al.: Criteria for Pacemaker Explant in Patients Without a Precise Indication for Pacemaker Implantation. Unnecessary pacemaker implantation may cause significant social and psychological consequences, the inconvenience of periodic office visits, and the expense of pulse generator replacement. Establishing adequate criteria for explanting pacemakers is crucial and has not yet been described. This study presents the results of a study protocol for explanting the pacemaker in patients without a clear indication for pacemaker implantation. Seventy pacemaker users without a clear reason for the implantation were included in the study conducted from August 1986 to November 1998 and were prospectively followed. The investigation consisted of clinical and neurological evaluations, echocardiogram, exercise testing, and tilt table testing. When these tests were negative, the pulse generator energy and stimulation rates were reprogrammed to the lowest values. Periodic Holter monitoring was conducted during follow-up. When asymptomatic for 1 year, patients underwent an electrophysiological evaluation of sinus and atrioventricular junction function and ventricular vulnerability. When the electrophysiological study was negative, pacemaker explantation was performed. Of the 70 patients, 35 had their pacemaker explanted; 3 were excluded due to a positive tilt table test and electrophysiological study, and 3 are waiting for pacemaker explantation. Mean follow-up after pacemaker explantation was 30.3 months, and all patients remained asymptomatic, except for one patient who died of a noncardiac cause. Critical analysis of pacemaker users without a well-established indication is justified because it may allow pacemaker explant in a significant proportion of these patients, and it may bring considerable social, economic, and psychological benefits. [source]

Changes in Quality-of-Life After Pacemaker Implantation: Responsiveness of the Aquarel Questionnaire

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 3 2001
MONIQUE A. M. STOFMEEL
STOFMEEL, M.A.M., et al.: Changes in Quality-of-Life After Pacemaker Implantation: Responsiveness of the Aquarel Questionnaire. Before being introduced for widespread use, health status instruments should be evaluated for reliability, validity, and responsiveness to relevant clinical changes. In a previous study the validity and reliability of Aquarel, a disease-specific quality-of-life (QOL) questionnaire for pacemaker patients, were tested and found satisfactory. The purpose of this study was to assess the sensitivity to change in health of Aquarel. A cohort of 51 patients was assessed at baseline and at 4,6 weeks after pacemaker implantation. We compared the sensitivity to change over time on the Aquarel scores to the scores on the SF-36 using various techniques (t -test value, effect size, standard error of measurement). Using the 1-standard error of measurement (SEM) criterion for clinically relevant change, Aquarel seemed to provide better classification of patients compared to the SF-36 alone. This study supports the value of Aquarel as a disease-specific measure of QOL in pacemaker patients. [source]

A Cosmetic Approach for Pectoral Pacemaker Implantation in Young Girls

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 9 2000
ERIC ROSENTHAL
Pectoral placement of pacemaker generators, combined with use of a redundant intravascular lead portion, reduces the need for endocardial lead advancement during growth in children. While the use of small generators and submuscular pockets has contributed to cosmetic acceptability, the conventional subclavicular incision may occasionally form a keloid scar that is unacceptable in young girls. A modified implantation technique was used in five girls (age 2.6,13.3 years) during implantation of VDD (n = 2), VVIR (n = 2), and DDDR (n = 1) pacemakers. A 5-cm incision was made in the axilla along the line of the pec-toralis major and dissection was continued below the muscle to create a pocket for the generator. Subclavian vein puncture was performed from the axillary incision and beneath the pectoralis major muscle using standard or extra long needles with a needle guard. Peel away sheaths were used for lead positioning. The generator was placed in the submuscular pocket and the wound closed with absorbable sutures. At follow-up, pacemaker function was excellent and neither the scars nor pacemakers were visible from the front. In conclusion, the axillary incision with direct subclavian vein puncture from below the pectoralis major muscle offers the advantages of pectoral pacemaker implantation through a single cosmetic incision. [source]

Safety of Pacemaker Implantation Prior to Radiofrequency Ablation of Atrioventricular Junction in a Single Session Procedure

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 6 2000
ALESSANDRO PROCLEMER
RF current delivery may cause acute and chronic dysfunction of previously implanted pacemakers. The aim of this study was to assess prospectively the effects of RF energy on Thera I and Kappa pacemakers in 70 consecutive patients (mean age 70 ± 11 years, mean left ventricular ejection fraction 48 ± 15%) who underwent RF ablation of the AV junction for antiarrhythmic drug refractory atrial fibrillation (permanent in 42 patients, paroxysmal in 28). These pacing systems incorporate protection elements to avoid electromagnetic interference. The pacemakers (Thera DR 7960 I in 20 patients, Thera SR 8960 1 in 30, Kappa DR 600,601 in 8, Kappa SR 700,701 in 12) were implanted prior to RF ablation in a single session procedure and were transiently programmed to VVI mode at a rate of 30 beats/min. Capsure SP and Z unibipolar leads were used. During RF application there was continuous monitoring of three ECG leads, endocavitary electrograms, and event markers. Complete AV block was achieved in all cases after 3.6 ± 2.9 RF pulses and 100 ± 75 seconds of RF energy delivery. The mean time of pacemaker implantation and RF ablation was 60 ± 20 minutes. Transient or permanent pacemaker dysfunction including under/oversensing, reversion to a "noise-mode" pacing, pacing inhibition, reprogramming, or recycling were not observed. Leads impedance, sensing, and pacing thresholds remained in the normal range in the acute and long-term phase (average follow-up 18 ± 12 months). In conclusion, Thera I and Kappa pacemakers exhibit excellent protection against interference produced by RF current. The functional integrity of the pacemakers and Capsure leads was observed in the acute and chronic phases. Thus, the implantation of these pacing systems prior to RF ablation of the AV junction can be recommended. [source]

Tricuspid Valve Malfunction and Ventricular Pacemaker Lead: Case Report and Review of the Literature

ECHOCARDIOGRAPHY, Issue 8 2006
Said B. Iskandar M.D.
Pacemaker implantation can be associated with several complications, including myocardial perforation with or without pericardial effusion, venous thrombosis, vegetations of the tricuspid valve (TV) or pacing lead, and tricuspid regurgitation (TR). The TR is thought to be derived from deformity or perforation of the TV by the pacing lead or secondary to atrioventricular discordance with asynchronous ventricular pacing. Severe TR can be deleterious to the patient because it raises the central venous pressure by increasing the right sided preload. Chronically, the increase in right sided blood volume can result in an increase in the right atrial pressure leading to a decrease in venous return and low cardiac output. Severe TR from leaflet adhesion to the pacemaker lead has not been reported before. With the aging of the population and the expanding use of pacemakers and implantable cardioverter defibrillators (ICD) in clinical practice, this complication may be seen more frequently. We present a patient diagnosed with severe TR, years after his pacemaker implantation. His TR was thought to be caused by adhesion of the tricuspid valve to his pacemaker lead. [source]

Real-Time Three-Dimensional Echocardiography in Diagnosis of Right Ventricular Pseudoaneurysm after Pacemaker Implantation

Risk Factors for Requirement of Permanent Pacemaker Implantation After Aortic Valve Replacement

Noninvasive Assessment of Cardiac Resynchronization Therapy for Congestive Heart Failure Using Myocardial Strain and Left Ventricular Peak Power as Parameters of Myocardial Synchrony and Function

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 12 2002
Ph.D., ZORAN B. POPOVI
Resynchronization Therapy for Heart Failure.Introduction: Although invasive studies have shown that cardiac resynchronization therapy by biventricular pacing improves left ventricular (LV) function in selected heart failure patients, it is impractical to apply such techniques in the clinical setting. The aim of this study was to assess the acute effects of cardiac resynchronization therapy by noninvasive techniques. Methods and Results: Twenty-two patients enrolled in the InSync trial (age 64 ± 9 years, 18 men and 4 women; all with ejection fraction <35% and QRS >130 msec) were studied 1 to 12 months after pacemaker implantation during pacing, and while ventricular pacing was inhibited. Regional myocardial strains of the interventricular septum, LV free wall, and right ventricular free wall were derived from color Doppler tissue echocardiography. Peak power index was calculated as a product of simultaneously recorded noninvasive blood pressure and pulse-wave (PW) Doppler velocity of the LV outflow tract. The Z ratio (sum of LV ejection and filling times divided by RR interval) and tei index were calculated from PW Doppler data. During pacing, overall regional strain improved (P = 0.01), while the LV strain coefficient of variation decreased from 2.7 ± 2.4 to 1.3 ± 0.7 (P = 0.009). Additionally, peak power index improved from 84 ± 24 to 94 ± 27 cm· mmHg/sec (P = 0.004). The Z ratio increased from 0.71 ± 0.08 to 0.78 ± 0.07 (P = 0.0005), while the tei index decreased from 0.86 ± 0.33 to 0.59 ± 0.16 (P = 0.0002). Conclusion: Using novel noninvasive indices, we demonstrated that cardiac resynchronization therapy improves LV performance. [source]

Bimodal RR Interval Distribution in Chronic Atrial Fibrillation:

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 5 2000
Impact of Dual Atrioventricular Nodal Physiology on Long-Term Rate Control after Catheter Ablation of the Posterior Atrionodal Input
Bimodal RR Interval Distribution, Introduction: Radiofrequency (RF) catheter modification of the AV node hi patients with atrial fibrillation (AF) is limited by an unpredictable decrease of the ventricular rate and a wish incidence of permanent AV block, A bimodal RR histogram has been suggested to serve as a predictor for successful outcome but the corresponding AV node properties have never been characterized, We hypothesized that a bimodal histogram indicates dual AV nodal physiology and predicts a better outcome after AV node modification in chronic AF. Methods and Results: Thirty-seven patients were prospectively subdivided into two groups according to the RR histogram of 24-hour ECC monitoring, Before to RF ablation, internal cardioversion and programmed stimulation were performed, Among the 22 patients (group I) with a bimodal RR histogram, dual AV nodal physiology was found in 17 (779f) patients, Ablation significantly decreased ventricular rate with loss of the peak of short RR cycles after ablation (mean and maximal ventricular rates: 32% and 35% rate reduction, respectively; P < 0,01), In 15 patients with a unimodal RR histogram (group II), dual AV nodal physiology was found in 2 (13%), and rate reductions were 16% and 17%, respectively, At 6 months, 3 (14%) patients in group 1 and 6 (40%) in group II underwent elective AV nodal ablation with pacemaker implantation due to intolerable rapid ventricular response to AF. Conclusion: Bimodal RR interval distribution during chronic AF suggests the presence of dual AV nodal physiology and predicts a better outcome of RF ablation of the posterior atrionocdal input. [source]

Predictors of Complete Heart Block After Alcohol Septal Ablation for Hypertrophic Cardiomyopathy and the Timing of Pacemaker Implantation

Results of pacemaker implantation in 104 dogs

JOURNAL OF SMALL ANIMAL PRACTICE, Issue 1 2007
M. S. Johnson
Objectives: To document the outcome, survival and complications involved in pacemaker implantation in dogs in a retrospective study. Methods: Case records for all dogs in which pacemaker implantation was performed were reviewed. Results: A total of 104 dogs underwent pacemaker implantation. Dogs were presented with atrioventricular (AV) block (71), sick sinus syndrome (25) or vasovagal syncope (eight). Age at presentation varied from six months to 13 years with a median age of seven years and two months. The Labrador was the most commonly represented breed (17 cases). All but one dog survived pacemaker implantation, with 93 showing resolution of their clinical signs while 10 dogs showed intermittent residual signs. One-, three- and five-year survival estimates were 86, 65 and 39 per cent, respectively. Major complications after implantation were documented in 15 dogs and three of these led to fatalities. Minor complications were noted in 23 dogs. Sudden death occurred in six dogs three to 55 months following successful pacemaker implantation. Clinical Significance: Transvenous pacemaker implantation was successful in reducing or eliminating clinical signs in over 90 per cent of dogs with third-degree atrioventricular (AV) block or sick sinus syndrome. In dogs with vasovagal syncope, six of eight dogs had greatly reduced frequency of collapse and two became asymptomatic. Although the procedure was associated with complications, these were rarely life threatening and good survival was documented in the majority of cases. [source]

Third-Degree Atrioventricular Block in 21 Cats (1997,2004)

JOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 1 2006
H.B. Kellum
The effect of 3rd-degree atrioventricular block on long-term outcome in cats is unknown. Clinical findings and long-term outcome of 21 cats with 3rd-degree atrioventricular block were studied retrospectively. Median age of cats studied was 14 years (range 7,19 years). Presenting signs included respiratory distress or collapse, but 6 cats had no clinical signs of disease. Eight cats had congestive heart failure (CHF) at the time that 3rd-degree atrioventricular block was detected. Heart rates ranged from 80 to 140 beats per minute (bpm; median 120 bpm) with no difference in heart rate between cats with and those without CHF. Eleven of 18 cats that had echocardiograms had structural cardiac disease, and 6 cats had cardiac changes consistent with concurrent systemic disease. No atrioventricular nodal lesions were detected by echocardiography. One cat had atrioventricular nodal lesions detected on histologic examination. Median survival of 14 cats that died or were euthanized was 386 days (range 1,2,013 days). Survival did not differ between cats with or without CHF or between cats with or without structural cardiac disease. Thirteen cats with 3rd-degree atrioventricular block survived >1 year after diagnosis, regardless of presenting signs or underlying cardiac disease. Third-degree heart block in cats is often not immediately life threatening. Survival was not affected by the presence of underlying heart disease or congestive heart failure at the time of presentation. Even cats with collapse might survive >1 year without pacemaker implantation. [source]

Severe Venous and Lymphatic Obstruction after Single-Chamber Pacemaker Implantation in a Patient with Chest Radiation Therapy

Right Ventricular Septal Pacing: The Success of Stylet-Driven Active-Fixation Leads

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1 2010
RAPHAEL ROSSO M.D.
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 left anterior oblique (LAO) fluoroscopic projection. Such a projection is neither always used nor available during pacemaker implantation. The aim of this study was to evaluate how effective is the stylet-driven technique in septal lead placement guided only by posterior-anterior (PA) fluoroscopic view. Methods:One hundred consecutive patients with an indication for single- or dual-chamber pacing were enrolled. RV septal lead positioning was attempted in the PA projection only and confirmed by the LAO projection at the end of the procedure. Results:The RV lead position was septal in 90% of the patients. This included mid RV in 56 and RVOT in 34 patients. There were no significant differences in the mean stimulation threshold, R-wave sensing, and lead impedance between the two sites. In the RVOT, 97% (34/35) of leads were placed on the septum, whereas in the mid RV the value was 89% (56/63). Conclusions:The study confirms that conventional active-fixation pacing leads can be successfully and safely deployed onto the RV septum using a purposely-shaped stylet guided only by the PA fluoroscopic projection. (PACE 2010; 49,53) [source]

Impact of Right Ventricular Pacing Sites on Exercise Capacity during Ventricular Rate Regularization in Patients with Permanent Atrial Fibrillation

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 12 2009
HUNG-FAT TSE M.D., Ph.D.
Background:The deleterious effects of right ventricular apical (RVA) pacing may offset the potential benefit of ventricular rate (VR) regularization and rate adaptation during an exercise in patient's atrial fibrillation (AF). Methods:We studied 30 patients with permanent AF and symptomatic bradycardia who receive pacemaker implantation with RVA (n = 15) or right ventricular septal (RVS, n = 15) pacing. All the patients underwent an acute cardiopulmonary exercise testing using VVI-mode (VVI-OFF) and VVI-mode with VR regularization (VRR) algorithm on (VVI-ON). Results:There were no significant differences in the baseline characteristics between the two groups, except pacing QRS duration was significantly shorter during RVS pacing than RVA pacing (138.9 ± 5 vs 158.4 ± 6.1 ms, P = 0.035). Overall, VVI-ON mode increased the peak exercise VR, exercise time, metabolic equivalents (METs), and peak oxygen consumption (VO2max), and decreased the VR variability compared with VVI-OFF mode during exercise (P < 0.05), suggesting that VRR pacing improved exercise capacity during exercise. However, further analysis on the impact of VRR pacing with different pacing sites revealed that only patients with RVS pacing but not patients with RVA pacing had significant increased exercise time, METs, and VO2max during VVI-ON compared with VVI-OFF, despite similar changes in peaked exercise VR and VR variability. Conclusion:In patients with permanent AF, VRR pacing at RVS, but not at RVA, improved exercise capacity during exercise. [source]

Successful Cervical MR Scan in a Patient Several Hours after Pacemaker Implantation

Use of Radiofrequency Perforation for Lead Placement in Biventricular or Conventional Endocardial Pacing after Mustard or Senning Operations for D-Transposition of the Great Arteries

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 9 2009
SANTABHANU CHAKRABARTI M.D.
Background: Endocardial pacemaker lead placement can be challenging after Mustard and Senning operations for transposition of the great arteries (D-TGA), if there is atresia of the systemic venous pathways and because the coronary sinus cannot be used for cardiac resynchronization therapy. Radiofrequency (RF)-assisted perforation techniques have been used in congenital heart disease but have not been reported for use in pacemaker implantation. Methods and Results: We describe RF perforation of an atretic superior systemic venous pathway and systemic venous baffles in three patients after Senning and Mustard operations to implant endocardial pacing systems to achieve conventional or biventricular pacing. Conclusions: RF-energy-assisted perforation is feasible and effective tool to facilitate endocardial lead placement during dual-chamber and biventricular pacemaker implantation in patients with Mustard or Senning operations for D-TGA. [source]

Utility of Noninvasive, Mobile, Continuous Outpatient Rhythm Monitoring to Diagnose Seizure-Related Arrhythmias

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 7 2009
KEVIN DRIVER M.D.
The identification of patients with a diagnosis of seizure disorder who are also at risk for clinically significant bradycardia and/or tachycardia may require long-term cardiac rhythm monitoring. Noninvasive, continuous, outpatient cardiac rhythm monitoring may be useful for such clinical scenarios. The study group consisted of two male patients with a history of seizure disorder involving loss of consciousness. Clinical data and results of electrocardiography, echocardiography, electroencephelography, and continuous, mobile, outpatient cardiac rhythm monitoring are described. In the first patient, while cardiac bradyarrhythmias were secondary to seizures, sinus arrest most likely complicated the episodes by leading to more prolonged states of unconsciousness. In the second patient, permanent pacemaker implantation for AV block averted all clinical events previously attributed to seizures. Despite the different causal relationships between seizures and bradyarrhythmias in these two patients, mobile, cardiac outpatient telemetry was successful in diagnosing the contribution of cardiac dysrhythmia, leading to permanent pacemaker implantation. A diagnostic strategy that incorporates mobile, noninvasive, continuous, outpatient cardiac rhythm monitoring can effectively be utilized to diagnose significant seizure-related arrhythmias. [source]