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Implantable Cardioverter Defibrillator (implantable + cardioverter_defibrillator)
Terms modified by Implantable Cardioverter Defibrillator Selected AbstractsSupraventricular Arrhythmia Induction by an Implantable Cardioverter Defibrillator in a Patient with Hypertrophic CardiomyopathyPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 3 2010FARIBORZ AKBARZADEH M.D. A 23-year-old woman with obstructive hypertrophic cardiomyopathy and history of frequent unexplained syncope had undergone implantable cardioverter defibrillator implantation. She had experienced frequent inappropriate shocks since implantation due to T-wave oversensing. After one of the syncopal attacks, she was found to have an atrioventricular (AV)-reentrant tachycardia, induced by a high-voltage shock, with rapid degeneration to atrial fibrillation and then ventricular fibrillation. The AV-reentrant tachycardia was believed to be the cause of both syncopal attacks and inappropriate shocks. The patient has been asymptomatic after ablation of the accessory pathway. To the best of our knowledge, this is the first report of induction of an AV-reentrant tachycardia by a high-voltage implantable cardioverter defibrillator shock. (PACE 2010; 33:372,376) [source] Depression and Anxiety Status of Patients with Implantable Cardioverter Defibrillator and Precipitating FactorsPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 6 2006AHMET KAYA BILGE Background: Implantable cardioverter defibrillators (ICDs) are life-saving devices in treatment of life-threatening arrhythmia. We evaluate the emotional status of Turkish patients with ICD and try to explain factors that affect emotional status of the patients. Methods: Ninety-one patients with previously implanted ICD were included in the study. Follow-up periods, presence of ICD shock, shock frequency, time of the recent shock, age, and gender were noted. Depression and anxiety scores were evaluated according to Hospital Anxiety and Depression (HAD) chart. Results: Mean anxiety and depression scores were found as 9.1 ± 5.3 and 7.2 ± 5.1, respectively. According to HAD charts, 42 patients (46%) had anxiety and 37 patients (41%) had depression. Depression scores indicated significant difference between subgroups divided on the basis of follow-up periods (P = 0.026) and on the basis of time of recent shock (P = 0.028). There was significant difference in anxiety scores (P = 0.016) between patients with ICD shocks and patients with no shocks. When the patients were divided into subgroups according to shock frequency, both depression (P = 0.024) and anxiety (P = 0.016) scores presented significant difference. In female patients, depression and anxiety scores were found significantly higher compared to male patients (P = 0.046 and P = 0.016, respectively). In multivariate analysis, gender and shock frequency were found as predictors for anxiety scores (P = 0.019 and P = 0.044, respectively). However same analysis revealed no predictive factor for depression score. Conclusion: Our study indicates presence of depression and anxiety in nearly half of the patients with ICD. Consultation with psychiatry should be a part of the treatment for patients with ICD, especially for those who constitute high-risk groups. [source] Strategy for Safe Performance of Magnetic Resonance Imaging on a Patient with Implantable Cardioverter DefibrillatorPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 1 2006CLAAS PHILIP NAEHLE Clinically indicated magnetic resonance imaging (MRI) of the brain was safely performed at 1.5 T on a patient with an implantable cardioverter defibrillator (ICD). The ICD was reprogrammed to detection only, and imaging hardware and protocols were modified to minimize radiofrequency power deposition to the ICD system. The integrity of the ICD system was verified immediately post-MRI and after 6 weeks, including an ICD test with induction of ventricular fibrillation. This case demonstrates that in exceptional circumstances, in carefully selected patients, and using special precautions, an MRI exam of the brain may be possible in patients with ICDs. [source] Persistent Left Superior Vena Cava-Inferior Vena Caval Communication Complicating Implantation of an Implantable Cardioverter DefibrillatorPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 11 2005SANJEEV GOYAL A persistent left superior vena cava has been observed in 0.3% of the general population on autopsy. Its presence can complicate left-sided device implantation. Commonly, a LSVC connects to the right atrium via the coronary sinus. A LSVC-accessory hemiazygous-hemiazygous-inferior vena caval communication has not been described previously. The presence of such a congenital venous anomaly will prohibit a left-sided device implant. [source] Electrical Interference from an Abdominal Muscle Stimulator Unit on an Implantable Cardioverter Defibrillator:PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 5 2003Report of Two Consecutive Cases Two consecutive cases are presented of patients with ICDs in whom the use of commercial units for muscle stimulation for abdominal training caused interference with the device, mimicked cardiac signals, and resulted in inappropriate treatment shock delivery. (PACE 2003; 26:1292,1293) [source] Inhibition of Bradycardia Pacing and Detection of Ventricular Fibrillation Due to Far-Field Atrial Sensing in a Triple Chamber ImplantablePACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 10 2002DIRK VOLLMANN VOLLMANN, D., et al.: Inhibition of Bradycardia Pacing and Detection of Ventricular Fibrillation Due to Far-Field Atrial Sensing in a Triple Chamber Implantable Cardioverter Defibrillator. Oversensing of intracardiac signals or myopotentials may cause inappropriate ICD therapy. Reports on far-field sensing of atrial signals are rare, and inappropriate ICD therapy due to oversensing of atrial fibrillation has not yet been described. This report presents a patient with a triple chamber ICD and a history of His-bundle ablation who experienced asystolic ventricular pauses and inappropriate detection of ventricular fibrillation due to far-field oversensing of atrial fibrillation. Several factors contributed to the complication, which resolved after reduction of the ventricular sensitivity. [source] Use of a Single Coil Transvenous Electrode with an Abdominally Placed Implantable Cardioverter Defibrillator in ChildrenPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 5 2000PETER S. FISCHBACH While transvenous defibrillator electrode placement avoiding a thoracotomy is preferable, electrode size, a large intercoil spacing, and the need for subclavicular device placement preclude this approach in most children. We investigated a single RV coil to an abdominally placed active can ICD device. Five children ages 8,16 years (weight 21,50 kg, mean 35 kg) underwent ICD placement. Placement of a single coil Medtronic model 6932 or 6943 electrode was performed via the left subclavian vein approach and the electrode positioned in the RV apex with the coil lying along the RV diaphragmatic surface. The ICD (Medtronic Micro Jewel II model 7223Cx) was implanted in a left abdominal pocket with the lead tunneled from the infraclavicular region to the pocket. Implant DFTs were ± 15 J using a biphasic waveform. DFTs rechecked within 3-month postimplant were unchanged. Lead impedance at implant ranged from 38 to 56 ,, mean 51 ,. Follow-up was 3,21 months (total 82 months) with no electrode dislodgment. lead fractures, or inappropriate discharges. Two of the five patients have had successful appropriate ICD discharges. Transvenous ICD electrode placement can be performed in children as small as 20 kg with the device implanted in a cosmetically acceptable abdominal pocket that is well tolerated. Excellent DFTs can be achieved. This approach avoids a thoracotomy in all but the smallest child, does not require subclavicular placement of the device, and avoids use of a second intravascular coil. [source] Remote Monitoring of Implantable Cardioverter Defibrillators versus Quarterly Device Interrogations in Clinic: Results from a Randomized Pilot Clinical TrialJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 5 2010M.H.S., SANA M. AL-KHATIB M.D. ICD: Remote Monitoring Versus Clinic Interrogations.,Introduction: Remote monitoring is increasingly becoming the new standard of care for implantable cardioverter defibrillator (ICD) follow-up. We sought to determine whether remote monitoring of ICDs improves patient outcomes compared with quarterly device interrogations in clinic. Methods and Results: In this single-center pilot clinical trial, adult patients with an ICD were randomly assigned to remote monitoring versus quarterly device interrogations in clinic. The primary endpoint was a composite of cardiovascular hospitalization, emergency room visit for a cardiac cause, and unscheduled visit to the electrophysiology clinic for a device-related issue at 1 year. We also examined health-related quality of life, costs, and patient satisfaction with their ICD care. Of 151 patients enrolled in this trial, 76 were randomized to remote monitoring and 75 to quarterly device interrogations in clinic. There was no significant difference in the primary endpoint (32% in the remote monitoring arm vs 34% in the control arm; P = 0.8), mortality, or cost between the 2 arms. Quality of life and patient satisfaction were significantly better in the control arm than in the remote monitoring arm at 6 months (83 [25th, 75th percentiles 70, 90] vs 75 [50, 85]; P = 0.002 and 88 [75, 100] vs 75 [75, 88]; P = 0.03, respectively), but not at 12 months. Conclusion: We showed no significant reduction in cardiac-related resource utilization with remote monitoring of ICDs. However, given the small number of patients in our study, the real clinical and health economics impact of remote monitoring needs to be verified by a large, multicenter, randomized clinical trial. (J Cardiovasc Electrophysiol, Vol. 21, pp. 545-550, May 2010) [source] Implantable Cardioverter Defibrillators: Do Women Fare Worse Than Men?JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 9 2009Gender Comparison in the INTRINSIC RV Trial Introduction: Due to limited enrollment of women in previous trials, there is a paucity of data comparing outcome and arrhythmic events in men versus women with implantable cardioverter defibrillators (ICDs). Methods and Results: We analyzed outcome of patients in the INTRINSIC RV (Inhibition of Unnecessary RV Pacing with AV Search Hysteresis in ICDs) trial based on gender. Women comprised 19% (293/1530) of the INTRINSIC RV population. Compared with men, women were less likely to have coronary disease, ischemic cardiomyopathy, and hyperlipidemia, and were more likely to have congestive heart failure and diabetes. Women were less likely to receive beta blockers and ACE inhibitors, and more likely to receive diuretics. Over 10.8 ± 3.5 months of follow-up, unadjusted mortality was higher in women than men (6.8% vs 4.1%, P = 0.04). Heart failure hospitalizations occurred in 7.9% of women versus 5.7% of men (P = 0.13). After adjustment for baseline differences and drug therapy, there was no significant difference in mortality between men and women. Adverse events were observed more often in women. There were no gender differences in the percentage of patients receiving appropriate or inappropriate ICD shocks. Conclusions: In INTRINSIC RV, women receiving ICDs differed from men regarding baseline characteristics and drug therapy. After adjusting for baseline differences and medical therapy, there were no differences in heart failure hospitalization, survival, or ICD shock therapy during follow-up. Apparent undertreatment of heart failure and greater frequency of adverse advents in women receiving ICDs warrant further investigation. [source] Predictors of All-Cause Mortality for Patients with Chronic Chagas' Heart Disease Receiving Implantable Cardioverter Defibrillator TherapyJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 12 2007AUGUSTO CARDINALLI-NETO M.D., Ph.D. Background: Implantable Cardioverter Defibrillators (ICD) have sporadically been used in the treatment of either Sustained Ventricular Tachycardia (VT) or Ventricular Fibrillation (VF) in Chagas' disease patients. This study aimed at determining predictors of all-cause mortality for Chagas' disease patients receiving ICD therapy. Methods and Results: Ninety consecutive patients were entered the study. Mean left ventricular ejection fraction was 47 ± 13%. Twenty-five (28%) patients had no left ventricular systolic dysfunction. After device implantation, all patients were given amiodarone (mean daily dose = 331, 1 ± 153,3 mg), whereas a B-Blocking agent was given to 37 (40%) out of 90 patients. Results: A total of 4,274 arrhythmias were observed on stored electrogram in 64 (71%) out of 90 patients during the study period; SVT was observed in 45 out of 64 (70%) patients, and VF in 19 (30%) out of 64 patients. Twenty-six (29%) out of 90 patients had no arrhythmia. Fifty-eight (64%) out of 90 patients received appropriate shock, whereas Antitachycardia Pacing was delivered to 58 (64%) out of 90 patients. There were 31 (34%) deaths during the study period. Five patients were lost to follow up. Sudden cardiac death affected 2 (7%) out of 26 patients, whereas pump failure death was detected in the remaining 24 (93%) patients. Number of shocks per patient per 30 days was the only independent predictor of mortality. Conclusion: Number of shocks per patient per 30 days predicts outcome in Chagas' disease patients treated with ICD. [source] Cigarette Smoking and the Risk of Supraventricular and Ventricular Tachyarrhythmias in High-Risk Cardiac Patients with Implantable Cardioverter DefibrillatorsJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 9 2006ILAN GOLDENBERG M.D. Introduction: Nicotine elevates serum catecholamine concentration and is therefore potentially arrhythmogenic. However, the effect of cigarette smoking on arrhythmic risk in coronary heart disease patients is not well established. Methods and Results: The risk of appropriate and inappropriate defibrillator therapy by smoking status was analyzed in 717 patients who received an implantable cardioverter defibrillator (ICD) in the Multicenter Automatic Defibrillator Implantation Trial-II. Compared with patients who had quit smoking before study entry (past smokers) and patients who had never smoked (never smokers), patients who continued smoking (current smokers) were significantly younger and generally had more favorable baseline clinical characteristics. Despite this, the adjusted hazard ratio (HR) for appropriate ICD therapy for fast ventricular tachycardia (at heart rates ,180 b.p.m) or ventricular fibrillation was highest among current smokers (HR = 2.11 [95% CI 1.11,3.99]) and intermediate among past smokers (HR = 1.57 [95% CI 0.95,2.58]), as compared with never smokers (P for trend = 0.02). Current smokers also exhibited a higher risk of inappropriate ICD shocks (HR = 2.93 [95% CI 1.30,6.63]) than past (HR = 1.91 [95% CI 0.97,3.77]) and never smokers (P for trend = 0.008). Conclusions: In patients with ischemic left ventricular dysfunction, continued cigarette smoking is associated with a significant increase in the risk of life-threatening ventricular tachyarrhythmias and inappropriate ICD shocks induced by rapid supraventricular arrhythmias. Our findings stress the importance of complete smoking cessation in this high-risk population. [source] Implantable Cardioverter Defibrillators in Pediatric Patients:JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 1 2005Off-Label Devices for Orphan Diseases No abstract is available for this article. [source] Supraventricular Arrhythmias in Children and Young Adults with Implantable Cardioverter DefibrillatorsJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 10 2001BARRY A. LOVE M.D. SVT in Pediatric ICD Recipients.Introduction: Rapidly conducted supraventricular tachycardias (SVTs) can lead to inappropriate device therapy in implantable cardioverter defibrillator (ICD) patients. We sought to determine the incidence of SVTs and the occurrence of inappropriate ICD therapy due to SVT in a pediatric and young adult population. Methods and Results: We undertook a retrospective review of clinical course, Holter monitoring, and ICD interrogations of patients receiving ICD follow-up at our institution between March 1992 and December 1999. Of 81 new ICD implantations, 54 eligible patients (median age 16.5 years, range 1 to 48) were identified. Implantation indications included syncope and/or spontaneous/inducible ventricular arrhythmia with congenital heart disease (30), long QT syndrome (9), structurally normal heart (ventricular tachycardia/ventricular fibrillation [VT/VF]) (7), and cardiomyopathies (7). Sixteen patients (30%) received a dual-chamber ICD. SVT was recognized in 16 patients, with 12 of 16 having inducible or spontaneous atrial tachycardias. Eighteen patients (33%) received , 1 appropriate shock(s) for VT/VF; 8 patients (15%) received inappropriate therapy for SVT. Therapies were altered after an inappropriate shock by increasing the detection time or rate and/or increasing beta-blocker dosage. No single-chamber ICD was initially programmed with detection enhancements, such as sudden onset, rate stability, or QRS discriminators. Only one dual-chamber defibrillator was programmed with an atrial discrimination algorithm. Appropriate ICD therapy was not withheld due to detection parameters or SVT discrimination programming. Conclusion: SVT in children and young adults with ICDs is common. Inappropriate shocks due to SVT can be curtailed even without dual-chamber devices or specific SVT discrimination algorithms. [source] Are Routine Arrhythmia Inductions Necessary in Patients with Pectoral Implantable Cardioverter Defibrillators?JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 2 2000MICHAEL GLIKSON M.D. Routine Arrhythmia Inductions in Patients with ICDs. Introduction: The value of ventricular arrhythmia inductions as part of routine implantable cardioverter defibrillator (ICD) follow-up in new-generation pectoral ICDs is unknown Methods and Results: We performed a retrospective analysis of a prospectively collected database analyzing data from 153 patients with pectoral ICDs who had routine arrhythmia inductions at predismissal, and 3 months and 1 year after implantation. Routine predismissal ventricular fibrillation (VF) induction yielded important findings in 8.8% of patients, all in patients with implantation defibrillation threshold (DFT) , 15 J or with concomitant pacemaker systems. At 3 months and 1 year, routine VF induction yielded important findings in 5.9% and 3.8% of tested patients, respectively, all in patients who had high DFT on prior testing. Ventricular tachycardia (VT) induction at predismissal, and 3 months and 1 year after implantation resulted in programming change in 37.4%, 28.1%, and 13.8% of tested patients, almost all in patients with inducible VT on baseline electrophysiologic study and clinical episodes since implantation. Conclusion: Although helpful in identifying potentially important ICD malfunctions, routine arrhythmia inductions during the first year after ICD implantation may not be necessary in all cases. VF inductions have a low yield in patients with previously low DFTs who lack concomitant pacemakers. VT inductions have a low yield in patients without baseline Inducible VT and in the absence of clinical events. Definite recommendations regarding patient selection must await larger prospective studies as well as consensus in the medical community about what comprises an acceptable risk justifying avoidance of the costs and inconveniences of routine arrhythmia inductions. [source] Age-Specific Differences in Women with Implantable Cardioverter Defibrillators: An International Multi Center StudyPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 12 2008LAUREN D. VAZQUEZ M.S. Background: Common psychological adjustment difficulties have been identified for groups of implantable cardioverter defibrillator patients, such as those who are young (<50 years old), have been shocked, and are female. Specific aspects and concerns, such as fears of death or shock and body image concerns, that increase the chance of distress, have not been examined in different aged female implantable cardioverter defibrillator (ICD) recipients. The aim of the study was to investigate these areas of adjustment across three age groups of women from multiple centers. Methods: Eighty-eight female ICD patients were recruited at three medical centers: Shands Hospital at the University of Florida, Brigham and Women's Hospital in Boston, and Royal North Shore Hospital in Sydney, Australia. Women completed individual psychological assessment batteries, measuring the constructs of shock anxiety, death anxiety, and body image concerns. Medical record review was conducted for all patients regarding cardiac illnesses and ICD-specific data. Results: Multivariate and univariate analyses of variance revealed that younger women reported significantly higher rates of shock and death anxiety (Pillai's F = 3.053, P = 0.018, ,2p= 0.067) and significantly greater body image concerns (Pillai's F = 4.198, P = 0.018, ,2p= 0.090) than middle- and older-aged women. Conclusions: Women under the age of 50 appear to be at greater risk for the development of psychosocial distress associated with shock anxiety, death anxiety, and body image. Clinical-based strategies and interventions targeting these types of adjustment difficulties in younger women may allow for improved psychosocial and quality of life outcomes. [source] Mechanisms of Ventricular Fibrillation Initiation in MADIT II Patients with Implantable Cardioverter DefibrillatorsPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2 2008RYAN ANTHONY M.D. Background:The availability of stored intracardiac electrograms from implantable defibrillators (ICDs) has facilitated the study of the mechanisms of ventricular tachyarrhythmia onset. This study aimed to determine the patterns of initiation of ventricular fibrillation (VF) in Multicenter Automatic Defibrillator Implantation Trial (MADIT) II patients along with associated electrocardiogram (ECG) parameters and clinical characteristics. Methods:Examination of stored electrograms enabled us to evaluate the rhythm preceding each episode of VF and to calculate (intracardiac) ECG parameters including QT, QT peak (QTp), coupling interval, and prematurity index. Results:Sixty episodes of VF among 29 patients (mean age 64.4 ± 2.5 years) were identified. A single ventricular premature complex (VPC) initiated 46 (77%) episodes whereas a short-long-short (SLS) sequence accounted for 14 (23%) episodes. Of the 29 patients studied, 23 patients had VF episodes preceded by a VPC only, two patients with SLS only, and four patients with both VPC and SLS-initiated episodes. There were no significant differences between initiation patterns in regards to the measured ECG parameters; a faster heart rate with SLS initiation (mean RR prior to VF of 655 ± 104 ms for SLS and 744 ± 222 ms for VPC) approached significance (P = 0.06). The two patients with SLS only were not on ,-blockers compared to 83% of the VPC patients. Conclusion:Ventricular fibrillation is more commonly initiated by a VPC than by a SLS sequence among the MADIT II population. Current pacing modes designed to prevent bradycardia and pause-dependent arrhythmias are unlikely to decrease the incidence of VPC-initiated episodes of VF. [source] A Clinical Risk Score to Predict the Time to First Appropriate Device Therapy in Recipients of Implantable Cardioverter DefibrillatorsPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 3 2007HAITHAM HREYBE M.D. Background:To develop a risk score to predict the occurrence of appropriate defibrillator [implantable cardioverter-defibrillator (ICD)] therapies. A simple clinical score predicting the risk of appropriate ICD therapy is lacking. Methods:A Cox regression model was developed from a database of ICD patients at a single tertiary center to predict the time to appropriate ICD therapy defined as shock or antitachycardia pacing. A risk score was derived from this model using half of the database and was validated using the other half. Results:A total of 399 patients were entered into the database between July 2001 and February 2004. There were no statistically significant differences between the derivation (n = 200) and validation (n = 199) groups in any of the demographic or clinical variables recorded. The risk score included three independent variables: indication for ICD implantation (P = 0.03), serum creatinine level (P = 0.015), and QRS width (P = 0.028). The observed risk scores were highly predictive of time to ICD therapy in the validation group (P = 0.02). Conclusion:We describe a new clinical risk score that predicts the time to appropriate device therapy in ICD recipients of a single tertiary center hospital. The performance of this risk score needs to be investigated prospectively in a larger patient population. [source] Shock Coordinated with High Power of Morphology Electrogram Improves Defibrillation Success in Patients with Implantable Cardioverter DefibrillatorsPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 9 2002ALEXANDER BERKOWITSCH BERKOWITSCH, A., et al.: Shock Coordinated with High Power of Morphology Electrogram Improves Defibrillation Success in Patients with Implantable Cardioverter Defibrillators. Animal studies have suggested that the success of defibrillation may depend on the properties of VF waveform obtained from the morphology electrogram (ME) at the time of the shock. The reliable identification of depolarization events in the fibrillatory signal can be achieved using adaptive estimation of the instantaneous signal power (P). The aim of this study was to investigate if a high P of the ME (PME) was related to ventricular DFT and if the upslope in ME can be associated with the depolarization event. A total of 575 VF (mean duration 10 s) episodes recorded and stored during ICD implantation in 77 patients with ventricular arrhythmias were used for analysis. The DFT was defined using a double step-down test. The values of PME immediately before pulse delivery (Pshock) and shock outcomes were registered. The differences between Pshock of successful and failed defibrillation were tested with the Mann-Whitney U test. The relationship between individual medians of Pshock (Pmed) and DFT was analyzed using the Kruskall-Wallis H-test. The coincidence between identified depolarization and upslope in ME was tested using the chi-square test. A P value of 0.05 was set for an error probability. The Pshock in case of failed defibrillation was significantly lower than Pshock in successful cases by the pulses of any strength (P < 0.001). The test revealed a significant inverse correlation between Pmed and DFT with P < 0.001. The depolarization corresponded to the upslope of ME in 85% of cases. This study demonstrated that a high value of instantaneous power of ME indicates the optimal time for shock delivery. The implementation of this algorithm in ICDs may improve the defibrillation efficacy. [source] Preliminary Results with the Simultaneous Use of Implantable Cardioverter Defibrillators and Permanent Biventricular Pacemakers: Implications for Device Interaction and DevelopmentPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 3 2000S. WALKER We report our preliminary experience with the combined use of implantable cardioverter defibrillutors (ICD) and biventricular pacemakers in six patients with heart failure and malignant ventricular arrhythmia. Two patients underwent ICD implantation for malignant ventricular arrhythmia after previous biventricular pacemaker implantation. One patient underwent biventricular pacemaker insertion for NYHA Class III heart failure after previous ICD implantation. Two patients underwent single device implantation. In the sixth patient, a combined implantation failed due to an inability to obtain a satisfactory left ventricular pacemaker lead position. The potential for device interaction was explored during implantation. In two patients a potentially serious interaction was discovered. Subsequent alterations in device configuration and programming prevented these interactions with long-term use. No complication of combined device use has been demonstrated during a mean follow-up of 2 months (range 1-4 months). Satisfactory ICD and pacemaker function has also been demonstrated. We conclude that combined device implantation may be feasible with currently available pacing technology and that further prospective studies are required in this area. [source] QT Variability during Rest and Exercise in Patients with Implantable Cardioverter Defibrillators and Healthy ControlsANNALS OF NONINVASIVE ELECTROCARDIOLOGY, Issue 1 2009Mark C. Haigney M.D. Background: Increased QT Variability (QTVI) is predictive of life threatening arrhythmias in vulnerable patients. The predictive value of QTVI is based on resting ECGs, and little is known about the effect of acute exercise on QTVI. The relation between QTVI and arrhythmic vulnerability markers such as T-wave alternans (TWA) has also not been studied. This study examined the effects of exercise on QTVI and TWA in patients with arrhythmic vulnerability. Methods: Digitized ECGs were obtained from 47 ICD patients (43 males; age 60.9 ± 10.1) and 23 healthy controls (18 males; age 59.7 ± 9.5) during rest and bicycle exercise. QTVI was assessed using a previously validated algorithm and TWA was measured as both a continuous and a categorical variable based on a priori diagnostic criteria. Results: QTVI increased with exercise in ICD patients (,0.79 ± 0.11 to 0.36 ± 0.08, P < 0.001) and controls (,1.50 ± 0.07 to ,0.19 ± 0.12, P < 0.001), and QTVI levels were consistently higher in ICD patients than controls during rest and exercise (P < 0.001). The magnitude of QTVI increase from baseline levels was not larger among ICD patients versus controls (P > 0.20). Among ICD patients, elevated exercise QTVI was related to lower LV ejection fraction and inducibility of ischemia (P < 0.05). QTVI at rest correlated with exercise TWA (r = 0.54, P = 0.0004). Conclusions: QT variability increases significantly with exercise, and exercise QTVI is related to other well-documented markers of arrhythmic vulnerability, including low ejection fraction, inducible ischemia, and TWA. Resting QTVI may be useful in the risk stratification of individuals incapable of performing standard exercise protocols. [source] ChemInform Abstract: Room Temperature Synthesis of the Larger Power, High Silver Density Cathode Material Ag4V2O6F2 for Implantable Cardioverter Defibrillators.CHEMINFORM, Issue 40 2009Thomas A. Albrecht Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] ChemInform Abstract: Ag4V2O6F2 (SVOF): A High Silver Density Phase and Potential New Cathode Material for Implantable Cardioverter Defibrillators.CHEMINFORM, Issue 50 2008Frederic Sauvage Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Examination of Research Trends on Patient Factors in Patients with Implantable Cardioverter Defibrillators,CLINICAL CARDIOLOGY, Issue 2 2007Lauren A. Stutts B.S. Abstract Background The implantable cardioverter defibrillator (ICD) is the most effective treatment available for terminating potentially life-threatening ventricular tachycardia and ventricular fibrillation and reducing the risk of mortality. Despite its established health benefits, ICD therapy is accompanied by a unique array of patient and psychological factors meriting ample research attention. The purpose of this paper is to examine research trends and results regarding patient factors in cardiac and ICD research and to discuss key areas for future research. Hypothesis: An increase in articles associated with patient factors in cardiac and ICD research will be shown over time. Methods: The Medical Subject Heading (MeSH) system in PubMed was used to index articles under a range of psychosocial headings for both cardiovascular disease and ICDs to quantify the frequency of articles published across time, the journals most frequently utilized, the most productive institutions, and the most common areas of inquiry. Results: A significant positive relationship was revealed between patient factors in cardiac research (r = 0.96, p<0.01) and ICD research (r = 0.88, p<0.01) over time. Research is limited by the small number of investigations and institutions. Of the 178 articles on patient factors in ICD research, the most frequent areas of inquiry were psychosocial treatment (70.79%), anxiety (33.15%), quality of life (32.02%), and depression (29.78%). Conclusion: Future research examining positive adjustment is warranted, especially in light of increased prophylactic ICD implantation and possible decreased treatment burden associated with decreased shocks. [source] Role of Transesophageal Echocardiography in Detecting Implantable Cardioverter Defibrillator Lead InfectionECHOCARDIOGRAPHY, Issue 3 2003Sanjeev Wasson Implantable cardioverter defibrillator (ICD) lead infection is a rare condition with reported incidence of 0.2% to 16%. It usually presents with persistent bacteremia or fever of unknown origin and requires high clinical suspicion for diagnosis. Whenever ICD lead infection is suspected, transesophageal echocardiography is the diagnostic technique of choice for detection and characterization of the lesions. Lead infections are extremely difficult to manage conservatively and surgical removal of the entire defibrillator system is recommended along with antimicrobial therapy. We describe a case of recurrent staphylococci bacteremia due to an ICD lead infection in a patient with arrhythmogenic right ventricular dysplasia. (ECHOCARDIOGRAPHY, Volume 20, April 2003) [source] Implantable cardioverter defibrillator in maintenance hemodialysis patients with ventricular tachyarrhythmias: A single-center experienceHEMODIALYSIS INTERNATIONAL, Issue 1 2009Itaru ITO Abstract Patients with hemodialysis (HD) are at risk of death due to cardiac arrhythmias, worsening congestive heart failure (CHF), and noncardiac causes. This study reviews our experience with the use of implantable cardioverter defibrillators (ICDs) in patients with ventricular tachycardia who are under maintenance HD. We retrospectively reviewed 71 consecutive patients who underwent an ICD implantation in our hospital. There were 11 patients under maintenance HD and 60 patients without HD. The group of patients with HD (HD group) was compared with the patients without HD (control group). The mean follow-up period was 30±9 vs. 39±4 months in the HD group vs. the control group, respectively. Among these patients, 6 in the HD group and 26 in the control group received appropriate ICD therapies. There was no difference in appropriate ICD therapy, time to the first therapy, and electrical storm between the 2 groups. In the HD group, 1 patient underwent surgical removal of the ICD system due to infective endocarditis. There were 5 deaths in the HD group (4 from CHF) and 8 deaths in the control group (4 from CHF). There were no sudden cardiac deaths or arrhythmic deaths in both groups of patients during the follow-up period. However, the overall death rate was significantly higher in the HD group (P<0.01). In HD patients, ICD therapy prevented arrhythmic death, but their rate of nonarrhythmic adverse outcomes was high. This risk-benefit association should be considered before implantation of the device. [source] Prophylactic Implantation of Cardioverter Defibrillators in Idiopathic Nonischemic Cardiomyopathy for the Primary Prevention of Death: A Narrative ReviewCLINICAL CARDIOLOGY, Issue 5 2010Cihan Cevik MD, FESC Implantable cardioverter defibrillator (ICD) therapy reduces sudden cardiac death rates and reduces mortality in patients with ischemic heart disease and low ejection fractions. One-third of the deaths in patients with nonischemic cardiomyopathy are sudden. However, the efficacy of ICDs in the primary prevention of death in these patients is less clear. The most common cause of mortality in patients treated with ICDs is heart failure progression. ICD shocks can cause direct myocardial injury, fibrosis, inflammation, and adverse psychological outcomes, and these changes may contribute to the ventricular dysfunction in patients who already have a significantly depressed ejection fraction. We have reviewed the published randomized controlled trials and meta-analysis of prophylactic ICD therapy in the primary prevention of death in patients with nonischemic cardiomyopathy. The individual randomized controlled trials do not report a statistically significant reduction of mortality unless the ICD treatment is added to cardiac resynchronization therapy, but the meta-analysis did show a significant mortality reduction and favored ICD therapy in these patients. Medical management of many study participants was suboptimal, at least based on current guidelines. The patients with non-ischemic cardiomyopathy have good outcomes with medical therapy, and ICD therapy in this relatively low-risk population needs better selection criteria. Copyright © 2010 Wiley Periodicals, Inc. [source] Australian implantable cardiac defibrillator recipients: Quality-of-life issuesINTERNATIONAL JOURNAL OF NURSING PRACTICE, Issue 2 2002Dianne Pelletier RN BSci(Nurs), DipEd, FRCNA, MasterSci(Soc) Implantable cardioverter defibrillators (ICDs) have become a well-established therapy for people experiencing potentially lethal dysrhythmias. Australian recipients' quality of life and adjustment to the device over time, device-related complications, shock and associated sensations, and potential sequelae have not been widely explored. This paper reports a longitudinal prospective study of Australian ICD recipients (n = 74) to determine their responses to the device, health-related quality of life over time and shock experiences. A questionnaire designed for the study and the Medical Outcomes Trust Quality of Life Instrument, the SF36, were completed by recipients prior to and at 3 and 12 months post insertion. Results show that quality of life decreased for general health and social function between 3 and 12 months. Nearly half (49%) of the recipients received shocks within 12 months and the majority (92%) of these experienced sequelae that could make driving hazardous. Half of the population (49%) were driving at 3 months and 69% by 12 months, including 67% of those who had been shocked. Twenty-seven percent were hospitalized with device-related complications. Driving, the shock experience and rehospitalization, the shock experience and driving behaviour are significant issues for those with the implanted device. While it is a limitation of the study that partners and carers were not included, these findings will also be of interest to them. [source] Defibrillation Threshold Testing: Tradition or Necessity?PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 5 2009CHRISTOF KOLB M.D. Implantable cardioverter defibrillators (ICDs) have become an essential tool for primary and secondary prevention of sudden cardiac death. Traditionally, defibrillation threshold (DFT) testing is part of the "lege artis" ICD implantation. Taking into consideration that the absolute mortality reduction in primary prevention trials is estimated around 8% and in secondary prevention trials around 7%, it is only in these patients that an acceptable DFT is expected to affect survival. Using a high-energy ICD, the likelihood of obtaining an inadequate DFT is about 2.5%. Thus, the number of patients needed to be subjected to DFT testing in order to avert one potential death is about 500. Application of antitachycardia pacing for rapid ventricular tachycardias further reduces the percentage of patients dependent on reliable ICD defibrillation capability. Thus, the mortality rate that can be prevented by DFT testing is below 0.2%. This contrasts a 0.4% risk of life-threatening complications and a low but not negligible mortality risk owed to the procedure. Although in light of these data the balance between DFT-related risk and benefit seems to tilt toward the former, insights gained from prospective randomized trials will clarify whether the abandonment of routine DFT testing can be claimed on a rightful basis. [source] Depression and Anxiety Status of Patients with Implantable Cardioverter Defibrillator and Precipitating FactorsPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 6 2006AHMET KAYA BILGE Background: Implantable cardioverter defibrillators (ICDs) are life-saving devices in treatment of life-threatening arrhythmia. We evaluate the emotional status of Turkish patients with ICD and try to explain factors that affect emotional status of the patients. Methods: Ninety-one patients with previously implanted ICD were included in the study. Follow-up periods, presence of ICD shock, shock frequency, time of the recent shock, age, and gender were noted. Depression and anxiety scores were evaluated according to Hospital Anxiety and Depression (HAD) chart. Results: Mean anxiety and depression scores were found as 9.1 ± 5.3 and 7.2 ± 5.1, respectively. According to HAD charts, 42 patients (46%) had anxiety and 37 patients (41%) had depression. Depression scores indicated significant difference between subgroups divided on the basis of follow-up periods (P = 0.026) and on the basis of time of recent shock (P = 0.028). There was significant difference in anxiety scores (P = 0.016) between patients with ICD shocks and patients with no shocks. When the patients were divided into subgroups according to shock frequency, both depression (P = 0.024) and anxiety (P = 0.016) scores presented significant difference. In female patients, depression and anxiety scores were found significantly higher compared to male patients (P = 0.046 and P = 0.016, respectively). In multivariate analysis, gender and shock frequency were found as predictors for anxiety scores (P = 0.019 and P = 0.044, respectively). However same analysis revealed no predictive factor for depression score. Conclusion: Our study indicates presence of depression and anxiety in nearly half of the patients with ICD. Consultation with psychiatry should be a part of the treatment for patients with ICD, especially for those who constitute high-risk groups. [source] Understanding Atrial Symptom Reports: Objective versus Subjective PredictorsPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 8 2005SAMUEL F. SEARS Background: Atrial fibrillation (AF) is the most common cardiac arrhythmia and is associated with a variety of symptoms such as dizziness, palpitations, shortness of breath, and other signs of heart failure, which in turn impact quality of life (QOL). Implantable cardioverter defibrillators with atrial therapies (ICDs-ATs) have been shown to reduce AF symptoms and improve QOL in select AF samples. Method: This study examined the strength of relationships between objective (device-detected AF events) versus subjective (emotional symptoms) data and AF symptoms (number) reported as part of the Patient Atrial Shock Survey of Acceptance and Tolerance Study (N = 96, 72% men, M age = 65, SD = 12). Depression and anxiety were assessed via the Center for Epidemiological Studies,Depression Scale and the-State Trait Anxiety Inventory. AF disease burden was measured via a number of device-detected AF episodes and the Atrial Tachyarrhythmia Symptom Severity Scale. Results: Hierarchical multiple regression analysis indicated that negative emotions accounted for a significant 13.2% of unique variance in AF symptom score (F change (1, 54) = 9.625, P = 0.003). On the other hand, the number of device-detected AF episodes accounted for non-significant 8.2% of unique variance in the AF symptom score (P = 0.167). The full model explained 25.7% of the variance in AF symptom score (F(6, 54) = 3.110, P = 0.011). Specifically, greater number of treated AF episodes (,= 0.251, P = 0.043) and higher levels of negative emotions (,= 0.369, P = 0.003) predicted greater number of reported AF symptoms. Conclusion: Therefore, psychological distress may be a significant confounding factor affecting patient's report of AF symptoms rather than the actual experience of recurrent AF episodes. [source] |