ICD Implantation (icd + implantation)

Distribution by Scientific Domains


Selected Abstracts


Habitual Cocaine Use Is Associated with High Defibrillation Threshold During ICD Implantation

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 7 2007
JAY CHEN M.D.
Background: Habitual cocaine use can lead to dilated cardiomyopathy (DCM) and sudden cardiac death. Based on prior clinical observations, we hypothesized that prior habitual cocaine use is a strong predictor of high defibrillation threshold (DFT) during implantable cardioverter-defibrillator (ICD) implant. Methods: We reviewed the medical records of 130 consecutive patients undergoing initial ICD implantation or revision at Parkland Hospital and the Dallas VA Hospital, Dallas, TX, from January 2002 to November 2005. Patient characteristics and DFT data were collected retrospectively. Results: The study group includes 11 patients (8.46%) who were identified as having a history of prior habitual cocaine use as demonstrated by history and urine toxicology; the rest (119 patients) form the control group. Cocaine-using patients tended to be younger (48.2 ± 10 vs 60.1 ± 12.3 years; P = 0.0026), were less likely to have coronary disease (36.3% vs 72.2%; P = 0.032), and had less comorbidity. The average DFT was 27.9 ± 7.8 J for all cocaine-using patients and 14.5 ± 4.1 J for noncocaine-using patients (P = 0.00018). In the cocaine-using group, three out of 11 patients required a subcutaneous array compared to none in the control group. Conclusions: Our results suggest that patients with a history of habitual cocaine use may be at increased risk to have a high DFT during ICD implantation. This is the first study to demonstrate such association. ICD implantation in patients with this history should be planned with these findings in mind, as larger output generators or subcutaneous arrays might be required. [source]


Defibrillation Testing at ICD Implantation: Are We Asking the Wrong Question?

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 5 2009
MICHAEL R. GOLD M.D., Ph.D.
No abstract is available for this article. [source]


ICD Implantation in Infants and Small Children: The Extracardiac Technique

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 12 2006
THOMAS KRIEBEL M.D.
Background: There is no clear methodology for implantation of an internal cardioverter-defibrillator (ICD) in infants and small children. The aim of this study was to assess efficacy and safety of an extracardiac ICD implantation technique in pediatric patients. Patients and Methods: An extracardiac ICD system was implanted in eight patients (age: 0.3,8 years; body weight: 4,29 kg). Under fluoroscopic guidance a defibrillator lead was tunneled subcutaneously starting from the anterior axillar line along the course of the 6th rib until almost reaching the vertebral column. After a partial inferior sternotomy, bipolar steroid-eluting sensing and pacing leads were sutured to the atrial wall (n = 2) and to the anterior wall of the right ventricle (n = 8). The ICD device was implanted as "active can" in the upper abdomen. Sensing, pacing, and defibrillation thresholds (DFTs) as well as impedances were verified intraoperatively and 3 months later, respectively. Results: In seven of eight patients, intraoperative DFT between subcutaneous lead and device was <15 J. In the eighth patient ICD implantation was technically not feasible due to a DFT >20 J. During follow-up (mean 14.5 months) appropriate and effective ICD discharges were noted in two patients. DFT remained stable after 3 months in four of six patients retested. A revision was required in one patient due to lead migration and in another patient due to a lead break. Conclusions: In infants and small children, extracardiac ICD implantation was technically feasible. Experience and follow-up are still limited. The course of the DFT is unknown, facing further growth of the patients. [source]


Implantable cardioverter defibrillator in maintenance hemodialysis patients with ventricular tachyarrhythmias: A single-center experience

HEMODIALYSIS INTERNATIONAL, Issue 1 2009
Itaru 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]


Are MADIT II Criteria for Implantable Cardioverter Defibrillator Implantation Appropriate for Chinese Patients?

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 3 2010
CHUNG-WAH SIU M.B.B.S.
MADIT II Criteria for Implantable Cardioverter.,Background: MADIT-II demonstrated that prophylactic implantation of an implantable cardioverter-defibrillator (ICD) device prevents sudden cardiac death (SCD) in patients with myocardial infarction (MI) and impaired left ventricular ejection fraction (LVEF). It remains unclear whether the MADIT-II criteria for ICD implantation are appropriate for Chinese patients. Methods and Results: We compared the clinical characteristics and outcome for a cohort of consecutive Chinese patients who satisfied MADIT-II criteria for ICD implantation with the original published MADIT-II population. Seventy consecutive patients who satisfied MADIT-II criteria but did not undergo ICD implantation (age: 67 years, male: 77%) were studied. Their baseline demographics were comparable with the original MADIT-II cohort with the exception of a higher incidence of diabetes mellitus. After follow-up of 35 months, most deaths (78%) were due to cardiac causes (72% due to SCD). The 2-year SCD rate (10.0%) was comparable with that of the MADIT-II conventional group (12.1%), but higher than the MADIT-II defibrillator group (4.9%). Similarly, the 2-year non-SCD rate was 3.0%, also comparable with the MADIT-II conventional group (4.6%), but lower than the MADIT-II defibrillator group (7.0%). Cox regression analysis revealed that advance NYHA function class (Hazard Ratio [HR]: 3.5, 95% Confidence Interval [CI]: 1.48,8.24, P = 0.004) and the lack of statin therapy (HR: 3.7, 95%CI: 1.35,10.17, P = 0.011) were independent predictors for mortality in the MADIT-II eligible patients. Conclusion: Chinese patients who satisfy MADIT-II criteria for ICD implantation are at similar risk of SCD and non-SCD as the original MADIT-II subjects. Implantation of an ICD in Chinese patients is appropriate. (J Cardiovasc Electrophysiol, Vol. 21, pp. 231,235, March 2010) [source]


Electrocardiographic Findings, Device Therapies, and Comorbidities in Octogenarian Implantable Defibrillator Recipients

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 3 2010
JAMES D. DANIELS M.D.
Implantable Defibrillators in Octogenarians.,Background: The use of implantable cardioverter-defibrillators (ICDs) in octogenarians is poorly defined. Objective: To assess baseline electrocardiographic (ECG) findings, arrhythmia episodes, and development of severe nonarrhythmic illness or death in patients aged ,80 years at ICD implantation, and to compare them with younger patients. Methods: Medical records and device interrogations for 199 patients ,70 years old who underwent ICD implantation were reviewed. Patients were divided into 3 groups based on age at the time of implant: age 70,74 (group 1; 88 patients), age 75,79 (group 2; 67 patients), and age ,80 (group 3; 44 patients). Results: ECGs: Octogenarians were more likely to have sinus bradycardia (SB) (P = 0.047) and left bundle branch block (LBBB) (P = 0.043) compared to younger patients. There was no difference among groups in the proportion of patients with atrial fibrillation or any degree of AV block. Therapies: There was no difference between age groups in any therapy (P = 0.78), appropriate therapy (P = 0.54), or inappropriate therapy (P = 0.21) per patient-year. There was no difference between groups in time-to-first therapy of any type (P = 0.71). Nonarrhythmic death/morbidity: There was no difference between groups in time to death or serious illness. Conclusion: Our study is the first to evaluate in detail the therapies received by octogenarians after ICD placement. The higher incidence of SB and LBBB might influence the number of pacing sites in octogenarian patients. Very elderly patients have similar rates of arrhythmic episodes and development of severe comorbidities as septuagenarians, and they should not be denied ICD implantation based solely on age. (J Cardiovasc Electrophysiol, Vol. 21, pp. 236,241, March 2010) [source]


Habitual Cocaine Use Is Associated with High Defibrillation Threshold During ICD Implantation

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 7 2007
JAY CHEN M.D.
Background: Habitual cocaine use can lead to dilated cardiomyopathy (DCM) and sudden cardiac death. Based on prior clinical observations, we hypothesized that prior habitual cocaine use is a strong predictor of high defibrillation threshold (DFT) during implantable cardioverter-defibrillator (ICD) implant. Methods: We reviewed the medical records of 130 consecutive patients undergoing initial ICD implantation or revision at Parkland Hospital and the Dallas VA Hospital, Dallas, TX, from January 2002 to November 2005. Patient characteristics and DFT data were collected retrospectively. Results: The study group includes 11 patients (8.46%) who were identified as having a history of prior habitual cocaine use as demonstrated by history and urine toxicology; the rest (119 patients) form the control group. Cocaine-using patients tended to be younger (48.2 ± 10 vs 60.1 ± 12.3 years; P = 0.0026), were less likely to have coronary disease (36.3% vs 72.2%; P = 0.032), and had less comorbidity. The average DFT was 27.9 ± 7.8 J for all cocaine-using patients and 14.5 ± 4.1 J for noncocaine-using patients (P = 0.00018). In the cocaine-using group, three out of 11 patients required a subcutaneous array compared to none in the control group. Conclusions: Our results suggest that patients with a history of habitual cocaine use may be at increased risk to have a high DFT during ICD implantation. This is the first study to demonstrate such association. ICD implantation in patients with this history should be planned with these findings in mind, as larger output generators or subcutaneous arrays might be required. [source]


Resynchronization or Dyssynchronization,Successful Treatment with Biventricular Stimulation of a Child with Obstructive Hypertrophic Cardiomyopathy without Dyssynchrony

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 5 2007
LENARCZYK RADOSLAW M.D.
CRT in a Child with Hypertrophic Cardiomyopathy. We present a case of a 10-year-old boy with hypertrophic cardiomyopathy, intraventricular pressure gradient of 104 mmHg, and indications for prophylactic ICD implantation. Based on intraoperative pressure measurements, the child was implanted with biventricular ICD. During 2.5 months of observation, the patient's functional status improved significantly, as shown by subjective and objective parameters and, moreover, the pressure gradient fell to 12 mmHg. Significant electrical and mechanical cardiac dyssynchrony appeared parallel to clinical improvement. [source]


Transvenous Cardioverter-Defibrillator Implantation in a Patient with Tricuspid Mechanical Prosthesis

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 3 2007
MAURO BIFFI M.D.
Background. A 64-year-old woman was referred to our center because of poorly tolerated ventricular tachycardia (VT) at 210 bpm due to an old myocardial infarction. The patient had been operated on at age of 20 for mitral valve commissurolysis, at age of 49 for ductal carcinoma, at age of 56 for mitral valve replacement, and at age of 61 for tricuspid valve replacement. Left ventricular EF was 31%. The patient was in permanent atrial fibrillation (AF) since the age of 53. She had undergone three cardiac surgery procedures, ending with two prosthetic mechanical valves. The cardiac surgery team advised against an epicardial ICD implantation. Results. We achieved a fully transvenous implant, with a screw-in defibrillation coil in the low right atrium and a bipolar pacing/sensing lead in a posterolateral branch of the coronary sinus. Pacing/sensing parameters were reliable, and effective defibrillation occurred at 20 J by a stepdown protocol. During 16-month follow-up, three VT episodes at 210 bpm were terminated by antitachycardia pacing (ATP) therapy. Left ventricular pacing/sensing was stable at long term. Conclusion. Thanks to technologic improvements, transvenous ICD implantation is feasible and safe in patients with a tricuspid mechanical prosthesis. [source]


Are Routine Arrhythmia Inductions Necessary in Patients with Pectoral Implantable Cardioverter Defibrillators?

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 2 2000
MICHAEL 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]


Defibrillation Threshold Testing: Tradition or Necessity?

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 5 2009
CHRISTOF 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]


Does ICD Indication Affect Quality of Life and Levels of Distress?

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2 2009
SUSANNE S. PEDERSEN Ph.D.
The implantable cardioverter defibrillator (ICD) is the treatment of choice for life-threatening arrhythmias, with ICD indications having recently been extended to include primary prophylaxis. Despite the medical benefits of the ICD, there is an ongoing debate as to the impact of the ICD on patients' lives, particularly whether primary prophylaxis implantation may impact adversely on patient-centered outcomes such as quality of life (QoL) and distress. We examined the evidence for a role of ICD indication on these patient-centered outcomes. A literature search was conducted on PubMed and Web of Science from 2002 to present, focusing on indication for ICD therapy and patient-centered outcomes (i.e., anxiety, depression, disease-specific, or general QoL). We identified five studies (seven articles) concerning the impact of indication on patient-centered outcomes. Sample sizes varied from 91,426 patients across studies, five of seven articles used a prospective design, and follow-up ranged from 2,12 months. No study reported an effect for indication on patient-centered outcomes. There is no evidence to suggest that patients receiving an ICD for primary prophylaxis have subsequent poorer QoL and greater distress than patients receiving an ICD for secondary prophylaxis. This knowledge may help cardiologists in the clinical management of patients, in particular when discussing ICD implantation with patients. [source]


Effect of Transvenous Cardiac Resynchronization Therapy Device Implantation on Cardiac Troponin I Release

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 11 2007
TIMUCIN ALTIN M.D.
Background: Pacemaker and implantable cardioverter defibrillator (ICD) implantation increases cardiac troponin I (cTnI) levels which indicates myocardial injury. During implantation of a cardiac resynchronization therapy (CRT) device, balloon inflation for coronary sinus (CS) venogram, cannulation of CS side branch, and electrode advancement may interfere with CS drainage and, hence, may decrease the washout of toxic metabolites from the heart. Thus, CRT implantation may further increase cTnI levels. In this study, we investigated the effects of CRT implantation on cTnI release. Methods: We included 10 patients (mean age = 57 ± 15 years) in whom a successful transvenous CRT system was implanted (CRT group). Twenty patients (mean age = 65 ± 10 years) who underwent a transvenous pacemaker or ICD implantation were included as the control group. Blood samples for cTnI were drawn at baseline and at six, 12, 18, and 24 hours thereafter. Results: Baseline median cTnI levels were similar in CRT and control groups (0.03 ng/mL vs 0.02 ng/mL, respectively; P = 0.1). Postoperative cTnI levels during 24 hours were significantly higher in the CRT group (P < 0.05) by two-way repeated measures of analyis of variance. Post hoc analysis revealed that cTnI levels were higher at the 6th, 12th, 18th, and 24th hours compared to baseline levels (P < 0.001, P < 0.001, P < 0.01, and P < 0.01, respectively). There was a significant difference in the area under the curves (AUCs) of cTnI measurements (1.79 hr·ng/mL in the CRT group and 0.78 hr·ng/mL in the control group, P < 0.05). Conclusion: Postoperative cTnI levels were higher after CRT implantation than simple pacemaker/ICD implantation. This may be due to CS manipulation during CRT implantation. [source]


Impact of Renal Function on Survival in Patients with Implantable Cardioverter-Defibrillators

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 3 2007
MINTU P. TURAKHIA M.D.
Background:Although chronic renal insufficiency (CRI) is associated with increased cardiac and noncardiac mortality, there is limited data on the relationship between CRI and survival in patients with implantable cardioverter-defibrillators (ICDs), particularly across a wide range of renal function. Methods:We studied 507 consecutive patients receiving first-time ICDs from 1993,2003 at a single center. Preimplant serum creatinine measurements were used to determine glomerular filtration rate (GFR) and stage of chronic kidney disease (CKD). The primary outcome was time to death. Results:During a mean follow-up of 4 years, all-cause mortality through completion of follow-up increased stepwise by GFR stage (I: 16%, II: 20%, III: 35%; IV: 40%; V: 50%; P < 0.001 for trend). After multivariate adjustment, CRI was independently associated with death (HR = 1.7, P = 0.02), as were a serum creatinine ,2.0 mg/dL (HR 2.5, P = 0.003) and the presence of end-stage renal disease (HR 6.8; P < 0.001). For every 10-unit decrease in GFR, the adjusted hazard of death increased 12% (P = 0.04). Conclusion:The presence of CRI prior to implant is independently associated with increased mortality in patients receiving ICDs. The risk is proportional to the degree of renal dysfunction and is apparent even when GFR is only mildly reduced. Differences in mortality are observed within the first year of implant, and patients on dialysis are at highest risk. Because randomized trials of ICDs have not included large numbers of patients with moderate or severe renal disease, our findings may have important implications in prognosis and case selection of patients who otherwise meet current indications for ICD implantation. [source]


A Clinical Risk Score to Predict the Time to First Appropriate Device Therapy in Recipients of Implantable Cardioverter Defibrillators

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 3 2007
HAITHAM 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]


A Comparison of ICD Implantations in the United States Versus Italy

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2007
STEVEN M. GREENBERG M.D.
Background: The benefits conferred by implantable cardioverter defibrillators (ICDs) have expanded to primary prevention. The advancements in ICD therapy (ACT) registry in the United States and the Italian ICD registry (IIR) examine changing trends in ICD implantation in their respective countries. Data from these registries may be useful for comparison of transcontinental differences in ICD utilization. Methods: This study includes initial implantations in patients enrolled in ACT and IIR. A comparative analysis was performed for device indications based on primary or secondary prevention. Sub-group analyses by device types (single, dual chamber, or cardiac resynchronization) were performed. Results: This analysis included 4,547 primary implantations in ACT and 6,491 in IIR. The groups were similar with respect to age. There were 82% primary and 18% secondary prevention indications in ACT, versus 42% primary and 58% secondary prevention indications in IIR (P < 0.001). There was a significantly higher rate of dual chamber ICD implants in ACT than in IIR for both primary (35.7% vs 23.7%, P < 0.001) and secondary prevention (52.3% vs 36.9%, P < 0.001). Conversely, more CRT-D were implanted in IIR than in ACT (primary prevention 46.5% vs 32.0%; secondary prevention 29.0% vs 13.0%, P < 0.001). Conclusions: Significant differences were observed in the types of indications for ICDs between ACT and IIR. Device prescription differed significantly between countries. The specific reasons for differences in ICD implantation patterns in these two countries are unclear. These observations warrant further investigations to determine if these differences are associated with different qualities of life and clinical outcomes. [source]


ICD Implantation in Infants and Small Children: The Extracardiac Technique

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 12 2006
THOMAS KRIEBEL M.D.
Background: There is no clear methodology for implantation of an internal cardioverter-defibrillator (ICD) in infants and small children. The aim of this study was to assess efficacy and safety of an extracardiac ICD implantation technique in pediatric patients. Patients and Methods: An extracardiac ICD system was implanted in eight patients (age: 0.3,8 years; body weight: 4,29 kg). Under fluoroscopic guidance a defibrillator lead was tunneled subcutaneously starting from the anterior axillar line along the course of the 6th rib until almost reaching the vertebral column. After a partial inferior sternotomy, bipolar steroid-eluting sensing and pacing leads were sutured to the atrial wall (n = 2) and to the anterior wall of the right ventricle (n = 8). The ICD device was implanted as "active can" in the upper abdomen. Sensing, pacing, and defibrillation thresholds (DFTs) as well as impedances were verified intraoperatively and 3 months later, respectively. Results: In seven of eight patients, intraoperative DFT between subcutaneous lead and device was <15 J. In the eighth patient ICD implantation was technically not feasible due to a DFT >20 J. During follow-up (mean 14.5 months) appropriate and effective ICD discharges were noted in two patients. DFT remained stable after 3 months in four of six patients retested. A revision was required in one patient due to lead migration and in another patient due to a lead break. Conclusions: In infants and small children, extracardiac ICD implantation was technically feasible. Experience and follow-up are still limited. The course of the DFT is unknown, facing further growth of the patients. [source]


Innovative Techniques for Placement of Implantable Cardioverter-Defibrillator Leads in Patients with Limited Venous Access to the Heart

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 2 2006
BRYAN C. CANNON
Background: Because of venous occlusion, intracardiac shunting, previous surgery, or small size placement of implantable cardioverter-defibrillator (ICD) leads may not be possible using traditional methods. The purpose of this study was to evaluate and describe innovative methods of placing ICD leads. Methods: The records of all patients undergoing ICD implantation at our institution were reviewed to identify patients with nontraditional lead placement. Indications for ICD, method of lead and coil placement, defibrillation thresholds, complications, and follow-up results were reviewed retrospectively. Results: Eight patients (aged 11 months to 29 years) were identified. Six patients with limited venous access to the heart (four extracardiac Fontan, one bidirectional Glenn, one 8 kg 11-month-old) underwent surgical placement of an ICD coil directly into the pericardial sac. A second bipolar lead was placed on the ventricle for sensing and pacing. Two patients with difficult venous access had a standard transvenous ICD lead inserted directly into the right atrium (transatrial approach) and then positioned into the ventricle. All patients had a defibrillation threshold of <20 J, although one patient required placement of a second coil due to an elevated threshold. There have been no complications and two successful appropriate ICD discharges at follow-up (median 22 months, range 5,42 months). Conclusions: Many factors may prohibit transvenous ICD lead placement. Nontraditional surgical placement of subcutaneous ICD leads on the pericardium or the use of a transatrial approach can be effective techniques in these patients. These procedures can be performed at low risk to the patient with excellent defibrillation thresholds. [source]


The Dual Chamber and VVI Implantable Defibrillator (DAVID) Trial

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 7p1 2003
Bruce L. Wilkoff
Introduction: The devices used to prove the benefit of ICD therapy had only VVI pacing but most current ICD devices provide dual chamber pacing therapy. The DAVID trial sought to measure the impact of dual chamber pacing at 70 bpm (DDDR-70) vs. ventricular backup pacing at 40 bpm (VVI-40) in patients with standard indications for ICD implantation but without indications for bradycardia pacing. Methods: This single-blind, multicenter, parallel-group, randomized clinical trial enrolled 506 patients with indications for ICD therapy between 10/2000 and 9/2002. All patients had an LVEF ,0.40, no indication for pacemaker therapy and no persistent atrial arrhythmias. ICDs with dual chamber, rate-responsive pacing capability were implanted and programmed to VVI-40 or DDDR-70. Results: The combined endpoint of mortality or hospitalization for congestive heart failure (CHF) at one year was 16.1% (VVI-40) vs. 26.7% (DDDR-70), (p , 0.03), mortality 6.5% vs. 10.1% (p , 0.15) and CHF hospitalization 13.3% vs. 22.5% (p , 0.07). Conclusion: For ICD patients, DDDR-70 pacing exhibits no clinical advantage over VVI-40 pacing and may increase CHF and mortality. [source]


Shock Coordinated with High Power of Morphology Electrogram Improves Defibrillation Success in Patients with Implantable Cardioverter Defibrillators

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 9 2002
ALEXANDER 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 Development

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 3 2000
S. 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]


Examination of Research Trends on Patient Factors in Patients with Implantable Cardioverter Defibrillators,

CLINICAL CARDIOLOGY, Issue 2 2007
Lauren 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]


Prognosis after ICD implantation

CLINICAL CARDIOLOGY, Issue 11 2001
C. Richard Conti M.D., M.A.C.C. Editor-in-Chief
No abstract is available for this article. [source]


Supraventricular Arrhythmias in Children and Young Adults with Implantable Cardioverter Defibrillators

JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 10 2001
BARRY 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]