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Objectives: The present study investigated whether regional anesthetic techniques, especially truncal blocks, can provide adjunct anesthesia without the additional risk of general anesthesia and neuraxial techniques for subcutaneous implantable cardioverter-defibrillator (S-ICD) implantation., Design: Single-center, prospective, randomized study., Setting: Holding area and operating room at a single-center tertiary care hospital., Participants: The study comprised 22 American Society of Anesthesiologists (ASA) physical status 3 or 4 patients with severe cardiac disease undergoing S-ICD implantation., Interventions: Patients received either a combination of serratus anterior plane block and transversus thoracis plane block or surgical infiltration of local anesthetics., Measurements and Main Results: Perioperative analgesic medication in the fascial plane block group versus the surgical wound infiltration group, visual analog pain scale score (0-10), intraoperative vital signs, total procedure time, and length of stay in the intensive care unit were measured. Total intraoperative fentanyl requirements (µg) were significantly less in the truncal block group versus the surgical infiltration group (45 [25-50] v 90 [50-100]; p = 0.026), and no patients had any adverse sequelae related to the study. Median intraoperative propofol use in the surgical infiltration group was 66.48 (47.30-73.73) µg/kg/min, and 65.95 (51.86-104.86) µg/kg/min for the truncal block group. This difference between the groups was not statistically significant (p = 0.293)., Conclusions: The performance of both the serratus anterior plane block and transversus thoracis plane blocks for S-ICD implantation are appropriate and may have the benefit of decreasing intraoperative opioid requirements., Competing Interests: Conflict of Interest None., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Background: Surgical site bleeding and infection are potential complications after electrophysiology (EP) device implantation procedures. To date, there is a wide variety of tools for management of intraoperative bleeding but it still remains unclear what methods are preferred., Objective: The aim of our study is to compare the rate of complications in patients who underwent cardiac implantable electronic device (CIED) implantation utilizing MPH hemostatic powder to the rate of complications in those patients who underwent standard procedure protocol without MPH hemostatic powder., Methods: In our study, a new plant-derived microporous polysaccharide hemostatic powder (Arista) was used. A total of 283 consecutive patients were retrospectively studied to assess the rate of complications in patients who underwent CIED implantation with MPH hemostatic powder (n = 77, MPH hemostatic powder) and without (n = 206, no MPH hemostatic powder). Patients were followed for 12 months., Results: The MPH hemostatic powder group of patients had a lower complication rate when compared to no MPH hemostatic powder, 0.3% vs. 1.7% (p < .05), respectively. The rate of device implantation site MPH hematoma in the MPH hemostatic powder group was 0.4%, versus 0.9% in the other group. There were no postoperative infections in the MPH hemostatic powder group versus 3.2% infections in the other group. The main predictor of increased risk of post-procedural complication was the usage of anticoagulation with a hazard ration of 2.7., Conclusion: Using MPH hemostatic powder for post-procedural hemostasis was shown to result in a significant reduction in the rate of overall post-procedural complications (a composite endpoint of hematoma and infections), and a trend in reduction of the infections rates and device implantation site hematoma rates.

Background: The perioperative anticoagulation management during subcutaneous implantable cardioverter-defibrillator (S-ICD) implantation is still evolving., Objective: The purpose of this study was to assess whether it is safe to perform S-ICD implantation with uninterrupted warfarin., Methods: This is a single-center retrospective review of patients undergoing S-ICD implantation between October 1, 2012 and June 30, 2017. One hundred thirty-seven patients underwent successful S-ICD implantation during the study period. The most common indication for implantation was primary prevention of sudden cardiac death. In 24 (17.5%) patients, warfarin was continued without any interruption (warfarin group). In 113 (82.5%) patients, no warfarin was used in the perioperative period (nonwarfarin group). The incidence of clinically significant lateral pocket hematoma was compared in the 2 groups., Results: The mean international normalized ratio was 1.83 ± 0.47 in the warfarin group and 1.09 ± 0.18 in the nonwarfarin group. A total of 8 patients developed a hematoma at the lateral pocket. No patient developed a hematoma at the parasternal pockets. Six patients (25%) in the warfarin group and 2 (1.5%) in the nonwarfarin group developed a significant lateral pocket hematoma (P = .001). The mean length of stay was longer in the warfarin group (1.23 ± 0.46 days) than in the nonwarfarin group (1.02 ± 0.18 days) (P = .0008). An international normalized ratio of >1.8 predicted the risk of hematoma. The concomitant use of dual antiplatelet therapy did not increase the risk of hematoma. None of the patients with a hematoma developed infection or required hematoma evacuation., Conclusion: Uninterrupted warfarin in the perioperative period during S-ICD implantation is associated with an increased risk of significant lateral pocket hematoma that results in prolonged hospital stay., (Copyright © 2017 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.)

Purpose: Cardiac sarcoidosis (CS) patients are at increased risk for sudden death. Isolated CS is rare and can be difficult to diagnose., Methods: In this multicenter retrospective review, patients with CS and an implantable cardiac defibrillator (ICD) were identified., Results: Of 235 patients with CS and ICD, 13 (5.5 %) had isolated CS, including 7 (3.0 %) with definite isolated CS (biopsy or necropsy-proven) and 6 (2.6 %) with suspected isolated CS based on a constellation of clinical, ECG, and imaging findings. Among 13 patients with isolated CS, 10 (76.9 %) were male, mean age was 53.8 ± 7.6 years, and mean left ventricular ejection fraction was 38.3 ± 16.5. Diagnosis was made by cardiac magnetic resonance (CMR) (n = 2), biopsy (n = 3), CMR and biopsy (n = 2), CMR and positron emission tomography (PET) (n = 2), PET (n = 1), late enhanced cardiac CT (n = 1), pathology at heart transplant (n = 1), and autopsy (n = 1). Eight of 13 (61.5 %) patients with isolated CS had a secondary prevention indication (VT in 6 and VF in 2) vs. 80 of 222 (36.0 %) with sarcoidosis in other organs (p = 0.04). Over a mean of 4.2 years, 9 of 13 (69.2 %) patients with isolated CS received appropriate ICD therapy, including anti-tachycardia pacing (ATP) and/or shock, compared with 75 of 222 (33.8 %) patients with cardiac and extracardiac sarcoidosis (p = 0.0150). Six of 7 (85.7 %) patients with definite isolated CS received appropriate ICD intervention, compared with 78 of 228 patients (34.2 %) without definite isolated CS (p = 0.0192.), Conclusions: In this retrospective study, patients with isolated CS had very high rates of appropriate ICD therapy. Prospective, long-term follow-up of consecutive patients with isolated CS is needed to determine the true natural history and rates of ventricular arrhythmias in this rare and difficult-to-diagnose disease.

Aims: Implantable cardiac defibrillator (ICD) implantation is a class IIA recommendation for patients with cardiac sarcoidosis (CS). However, little is known about the efficacy and safety of ICDs in this population. The goal of this multicentre retrospective data review was to evaluate the efficacy and safety of ICDs in patients with CS., Methods and Results: Electrophysiologists at academic medical centres were asked to identify consecutive patients with CS and an ICD. Clinical information, ICD therapy history, and device complications were collected for each patient. Data were collected on 235 patients from 13 institutions, 64.7% male with mean age 55.6 ± 11.1. Over a mean follow-up of 4.2 ± 4.0 years, 85 of 234 (36.2%) patients received an appropriate ICD therapy (shocks and/or anti-tachycardia pacing) and 67 of 226 (29.7%) received an appropriate shock. Fifty-seven of 235 patients (24.3%) received a total of 222 inappropriate shocks. Forty-six adverse events occurred in 41 of 235 patients (17.4%). Patients who received appropriate ICD therapies were more likely to be male (73.8 vs. 59.6%, P = 0.0330), have a history of syncope (40.5 vs. 22.5%, P = 0.0044), lower left ventricular ejection fraction (38.1 ± 15.2 vs. 48.8 ± 14.7%, P ≤ 0.0001), ventricular pacing on baseline electrocardiogram (16.1 vs. 2.1%, P = 0.0002), and a secondary prevention indication (60.7 vs. 24.5%, P < 0.0001) compared with those who did not receive appropriate ICD therapies., Conclusion: Patients with CS and ICDs are at high risk for ventricular arrhythmias. This population also has high rates of inappropriate shocks and device complications.

Background: Lead extraction is an effective method for removing pacemaker and defibrillator leads and to obtain venous access when central veins are occluded., Objective: We report a series of patients who required lead extraction and preservation of vascular access requiring a vascular snare introduced from the femoral vein to provide traction on the lead. This technique allowed advancement of the extraction sheath beyond the level of vascular occlusion, preserving vascular access in all patients., Methods: All patients had peripheral contrast venography performed immediately prior to the procedure to identify the site(s) of venous occlusion. An extraction sheath was employed and with direct manual traction, the lead tip pulled free from the myocardial surface prior to advancement of the sheath beyond the occlusion. A transfemoral snare was used to grasp the distal portion of the lead and traction was used to immobilize the lead., Results: In all patients, transfemoral snaring of the leads was necessary to allow safe advancement of a sheath to open the occluded venous system. There were no complications in any of the patients., Conclusion: Our series demonstrates the simple and safe technique of transfemoral lead snaring to assist lead extraction and maintain vascular access in the setting of venous occlusion, when the distal lead tip pulls free of the myocardium before an extraction sheath is passed beyond the point of venous obstruction.

Background: In the past 2 years, multiple implantable cardioverter-defibrillator (ICD) manufacturers have issued recalls on ICD models due to the potential for serious malfunction and even patient death. Previous studies examining the relationship between these recalls and patients' psychological well-being have been limited by small sample size and conflicting results. The purpose of this study is to examine the association between ICD recalls and patients' anxiety, depression, and quality of life., Methods: Patients were drawn from an outpatient electrophysiology clinic at a tertiary care hospital in New York City. Patients who had devices subject to a recall (cases) were identified from lists provided by device manufacturer and controls (patients with ICDs not subjected to a recall) were drawn from a convenience sample of outpatients. The survey instrument consisted of two validated questionnaires--Hospital Anxiety and Depression Score (HADS) and MacNew heart disease health-related quality of life (QOL) instrument. In addition, a series of Likert-type scales were designed to elucidate patients' concerns related to the following domains: anger, trust, hope, concerns regarding ICD shock, fear of death (FOD), and physicians' ability to reduce their concern about the ICD recall. Data were analyzed using simple descriptive statistics and bivariate analyses (chi(2) and t-test) as appropriate., Result: Sixty-one cases and 43 control patients were enrolled. Thirty-two patients (52%) with devices subject to a recall opted for a generator replacement. There were no significant differences in the mean scores on the HADS scale, or the MacNew QOL scale between these two groups of patients (cases and controls). Subgroup analysis within the group of patients whose ICDs were recalled (cases) revealed a reduced QOL among patients with a class I recall (reasonable probability that the product will cause serious adverse health consequences or death) as compared to those with a class II recall (product may cause temporary or medically reversible adverse health consequences) (P = 0.01). Both cases and control patients reported having reduced trust in the health-care system. On the whole, however, patients were satisfied with the way their physicians dealt with the recall. There was no significant change in the overall concern of ICD shocks or FOD between the two groups., Conclusion: In this study of ICD recall, we found no difference in the levels of anxiety, depression, or QOL expressed by patients with an ICD subject to a recall as compared to those without. These findings may be a reflection of good physician-patient communication, which might have reduced any anxiety associated with recalls.

Objective: To understand potential barriers to physician-initiated discussions about Implantable Cardioverter Defibrillator (ICD) deactivation in patients with advanced illness., Design: Qualitative one-on-one interviews., Participants: Four electrophysiologists, 4 cardiologists, and 4 generalists (internists and geriatricians) from 3 states., Approach: Clinicians were interviewed using open-ended questions to elicit their past experiences with discussing deactivating ICDs and to determine what barriers might impede these discussions. Transcripts of these interviews were analyzed using the qualitative method of constant comparison., Results: Although many physicians believed that conversations about deactivating ICDs should be included in advance care planning discussions, they acknowledged that they rarely did this. Physicians indicated that there was something intrinsic to the nature of these devices that makes it inherently difficult to think of them in the same context as other management decisions at the end of a patient's life. Other explanations physicians gave as to why they did not engage in conversations included: the small internal nature of these devices and hence absence of a physical reminder to discuss the ICD, the absence of an established relationship with the patient, and their own general concerns relating to withdrawing care., Conclusion: Whereas some of the barriers to discussing ICD deactivation are common to all forms of advance care planning, ICDs have unique characteristics that make these conversations more difficult. Future educational interventions will need to be designed to teach physicians how to improve communication with patients about the management of ICDs at the end of life.

Objective: To understand potential patient barriers to discussions about implantable cardioverter defibrillator (ICD) deactivation in patients with advanced illness., Design: Qualitative focus groups., Participants: Fifteen community-dwelling, ambulatory patients with ICDs assigned to focus groups based on duration of time since implantation and whether they had ever received a shock from their device., Approach: A physician and a social worker used a predetermined discussion guide to moderate the groups, and each session was audiotaped and subsequently transcribed. Transcripts were analyzed using the method of constant comparison., Results: No participant had ever discussed deactivation with their physician nor knew that deactivation was an option. Patients expressed a great deal of anxiety about receiving shocks from their device. Participants discussed why they needed the device and expressed desire for more information about the device; however, they would not engage in conversations about deactivating the ICD. One patient described deactivation "like an act of suicide" and all patients believed that the device was exclusively beneficial. Patients also expressed a desire to have their physician make the decision about deactivation., Conclusions: None of the patients in our study knew that they might need to deactivate their ICD as their health worsens. These community-dwelling outpatients were not willing to discuss the issue of ICD deactivation and their attitudes about deactivation might impede patients from engaging in these conversations. These findings are in contrast to findings in other advance care planning research and may be related to the unique nature of the ICD.

A case of successful laser extraction of a defibrillator lead with baffle stenting in a 15-year-old boy with dextrocardia, L-transposition, ventricular septal defect, and pulmonic stenosis status-post Senning/Rastelli repair is presented. Six-month follow-up revealed a significant increase in exercise tolerance and maximum oxygen consumption (VO(2)max).

Context: There has been a tremendous increase in the use of implantable cardioverter-defibrillators (ICDs) after several large clinical trials demonstrated their ability to effectively reduce mortality in selected populations of patients with cardiac disease. Thus, the nonelectrophysiologist will often encounter patients who have received an ICD shock., Objective: To assess options for the evaluation and management of patients who have received an ICD shock., Evidence Acquisition: Literature search using the PubMed and MEDLINE databases to identify articles published from January 1990 to September 2006, using the Medical Subject Headings defibrillators, implantable; defibrillators, implantable/adverse effects; anti-arrhythmic agents; electric countershock; quality of life; tachycardia therapy; algorithm; ventricular tachycardia/diagnosis; and supraventricular tachycardia/diagnosis. Case reports were excluded and articles were limited to those published in English. Scientific statements and guidelines from the American College of Cardiology, the American Heart Association, and the Heart Rhythm Society were also reviewed, as were the reference lists of retrieved articles, to identify any additional articles for inclusion., Evidence Synthesis: There are multiple causes of both appropriate and inappropriate ICD shocks. Irrespective of appropriateness, receiving ICD shocks substantially impairs a patient's quality of life. A variety of techniques are available using ICD programming to reliably limit the occurrence of appropriate or inappropriate ICD shocks. Antiarrhythmic medications can also effectively reduce the occurrence of shocks., Conclusions: Through the use of effective ICD programming and antiarrhythmic medications, the occurrence of ICD shocks can be reduced while maintaining the lifesaving ability of the ICD. A basic understanding of the range of available options is fundamental for evaluation and management of the patient who has received an ICD shock.

Objectives: We performed a meta-analysis of prognostic studies of patients with a Brugada ECG to assess predictors of events., Background: The Brugada syndrome is an increasingly recognized cause of idiopathic ventricular fibrillation; however, there is wide variation in the prognosis of patients with the Brugada ECG., Methods and Results: We retrieved 30 prospective studies of patients with the Brugada ECG, accumulating data on 1,545 patients. Summary estimates of the relative risk (RR) of events (sudden cardiac death [SCD], syncope, or internal defibrillator shock) for a variety of potential predictors were made using a random-effects model. The overall event rate at an average of 32 months follow-up was 10.0% (95% CI 8.5%, 11.5%). The RR of an event was increased (P < 0.001) among patients with a history of syncope or SCD (RR 3.24 [95% CI 2.13, 4.93]), men compared with women (RR 3.47 [95% CI 1.58, 7.63]), and patients with a spontaneous compared with sodium-channel blocker induced Type I Brugada ECG (RR 4.65 [95% CI 2.25, 9.58]). The RR of events was not significantly increased in patients with a family history of SCD (P = 0.97) or a mutation of the SCN5A gene (P = 0.18). The RR of events was also not significantly increased in patients inducible compared with noninducible by electrophysiologic study (EPS) (RR 1.88 [95% CI 0.62, 5.73], P = 0.27); however, there was significant heterogeneity of the studies included., Conclusions: Our findings suggest that a history of syncope or SCD, the presence of a spontaneous Type I Brugada ECG, and male gender predict a more malignant natural history. Our findings do not support the use of a family history of SCD, the presence of an SCN5A gene mutation, or EPS to guide the management of patients with a Brugada ECG.

Sudden cardiac death, usually due to fatal ventricular tachyarrhythmias, results in the loss of 300,000-400,000 lives each year in the United States. Implantable cardioverter-defibrillator therapy has revolutionized both the secondary and, increasingly, the primary prevention of sudden cardiac death. In the last decade, subcutaneous pectoral implantation with transvenous lead placement has lessened perioperative risk considerably, raising the benefit/risk ratio for many candidates. As a consequence, the list of approved indications for implantable cardioverter-defibrillator therapy has expanded rapidly in recent years. Current devices offer tiered therapy utilizing bradycardia pacing, anti-tachycardia pacing, low-energy cardioversion, and high-energy defibrillation. Hybrid therapy, combining device, drugs and radiofrequency catheter ablation as required, has become the standard of care for reducing both appropriate and inappropriate shocks. As implantation rates continue to rise, so will the number of patients presenting with electrical storm. The dilemma of how our society will cope with the enormous projected costs of implantable cardioverter-defibrillator therapy has yet to be resolved.

The control of life-threatening arrhythmias in the prevention of sudden cardiac death has been a long-standing challenge to clinicians. Large-scale, randomized, controlled trials have contributed immensely to our understanding of the management of life-threatening arrhythmias. There are many causes of life-threatening ventricular arrhythmias, which they occur mostly in the setting of healed myocardial infarction. Available treatments for the management of ventricular arrhythmias include antiarrhythmic drugs, implantable cardioverter defibrillators and catheter ablation. Each therapy provides unique advantages for selected patients with life-threatening arrhythmias. Because the goal of arrhythmia management is not only to provide the single best therapy but to provide the greatest assurance of symptomatic arrhythmia control, the use of combined therapy has become a standard treatment strategy for patients with sustained ventricular arrhythmias. This review will discuss the different modes of treatment available for the treatment of life-threatening ventricular arrhythmias, and their potential risks and benefits. The rationale for using hybrid or combination therapy will be presented. Finally, some of the better-known primary and secondary prevention trials for treatment of ventricular tachycardias will be reviewed.

Although medical therapy is the primary therapy for patients with heart failure, the use of pacemakers to improve cardiac hemodynamics is under investigation. Despite promising initial results, controlled studies have not verified the benefit of application of VDD or DDD pacing to a nonselected population of severely symptomatic congestive heart failure (CHF) patients to simply shorten their atrioventricular (AV) delay. There is increasing interest in pacing the left side of the heart or simultaneously pacing the right and left ventricles. Early studies suggest that these techniques may produce favorable hemodynamic effects in patients with CHF. Controlled, randomized studies are now underway. Further, it has been shown that sudden cardiac death accounts for 50% of deaths in patients with CHF. The value of an implantable cardioverter defibrillator (ICD) in secondary prevention of sudden cardiac death is well established. The use of ICD for primary prevention of sudden cardiac death in patients with CHF is being actively evaluated. Several large multicenter trials are underway, some combined with biventricular pacing, and should provide useful data in the coming years.

As the majority of ICDs with transvenous leads are now implanted in the pectoral region, complications associated with the technique are being identified. To determine the incidence of lead complications in patients with transvenous defibrillator leads and ICDs implanted in the pectoral region, 132 unselected consecutive patients with transvenous defibrillator leads had ICDs implanted in the pectoral region. Three lead systems were used: (1) lead system 1 (45 patients) consisted of a transvenous pacing sensing lead and a superior vena cava coil with a submuscular patch used for defibrillation; (2) lead system 2 (36 patients) utilized a CPI Endotak lead system; and (3) lead system 3 (51 patients) utilized a Medtronic Transvene lead system. Patients were followed for 3-54 months (cumulative 2,269, mean 18 months). The average duration of follow-up with the three systems was 32, 12 and 11 months, respectively. At 30 months follow-up, all three lead systems had a low incidence of complications. However, there was a 13% overall incidence (45% actuarial incidence) of erosion of the insulation of the pacing sensing lead of system 1 at 50 months of follow-up. All lead complications were seen in patients with ICDs whose weights were > 195 g and volumes > 115 cc. The erosion was probably a consequence of the pressure by the large ICD against the lead in the pectoral pocket. Follow-up with lead systems 2 and 3 is relatively short (average 12 months) but no lead erosions were seen. Pectoral implantation of ICDs with long transvenous leads and large generators is associated with a moderate risk of late complications in the form of insulation breaks caused by pressure of the generator against the leads. The use of less redundant leads coupled with smaller ICDs will probably eliminate this complication.

Analysis of stored electrograms from bipolar far-field electrodes is considered to be useful in differentiating supraventricular from ventricular arrhythmias. A case of inappropriate ICD shocks for sinus tachycardia is presented whereby successive shocks caused marked widening of the ventricular electrograms. Analysis of these stored electrograms, recorded from far-field bipolar electrodes, gave the false impression of ventricular tachycardia. The widening was due to the current of injury effects, probably a consequence of the large amount of intervening myocardium between the bipoles. While analyzing recordings from far-field bipolar electrodes is generally useful, it is not always reliable, for changes in electrogram morphology, relative to baseline rhythm, may result from other factors like current of injury.

A nonthoracotomy surgical approach using an endocardial electrode and combined implantation of a subcutaneous patch and the implantable cardioverter defibrillator (ICD) generator in a subpectoral pocket has been described. We report the long-term follow-up results in patients undergoing implantation using this approach. The patient population consisted of 28 patients (22 men and 6 women) with a mean age of 59 +/- 12 years. The underlying heart disease consisted of coronary artery disease in 20 patients and dilated cardiomyopathy in 8 patients. Sustained ventricular tachycardia was the mode of presentation in 16 patients and sudden cardiac death in 12 patients. The mean left ventricular ejection fraction was 31% +/- 6%. The lead system consisted of an 8 French bipolar passive fixation rate sensing lead positioned at the right ventricular apex, an 11 French spring coil electrode positioned at the superior vena cava-right atrial junction (surface area 700 mm2), and submuscular placement of a large patch (surface area 28 cm2) on the anterolateral chest wall near the cardiac apex via a submammary incision. A defibrillation threshold of < or = 15 joules (J) was required for implantation. This criterion was not satisfied in five patients; thus, a limited thoracotomy was performed via the submammary incision, and the large patch was placed epicardially. The mean R wave amplitude was 12 +/- 3 mV, the mean pacing threshold was 1.0 +/- 0.5 V at 0.5 msec, and the mean defibrillation threshold was 12.6 +/- 3 J. ICD generators implanted were the Ventak-P in 17, PCD-7217 in 5, and the Cadence V-100 in 6 patients.(ABSTRACT TRUNCATED AT 250 WORDS)

We describe a new approach to total pectoral implantation of cardioverter defibrillators with an endocardial defibrillation lead system. Endocardial lead configuration used was an FDA approved right atrial-superior vena cava defibrillation spring electrode, right ventricular bipolar sensing electrode, and a pectoral patch. Endocardial leads were implanted via a cephalic or an axillary venesection. Pectoral patch was placed in a submuscular position. In case of failure to obtain satisfactory thresholds, a small intercostal thoracotomy was performed via the same skin incision and patch placed over the epicardium instead of submuscular position and used with the right atrial spring electrode. The device was implanted in the pectoral region, submuscularly, over the patch. Sixteen consecutive patients underwent this approach. With a submuscular patch, adequate defibrillation thresholds (< or = 15 joules [J]) were obtained in 14 (87.5%) patients. In the other two, defibrillation thresholds of < or = 15 J were obtained with a epicardial patch. Pectoral implantation of the device was feasible in all 16 patients and none needed repositioning. Average postimplant hospital stay was 5 days. During follow-up period (average 5 months), none of the patients reported any major local symptoms and no problems have been encountered in device interrogation. Thus, total pectoral implantation of the cardioverter defibrillator including the patch, leads, and the device is feasible. Furthermore, in case of failure to obtain adequate defibrillation thresholds with submuscular patch, an epicardial patch can easily be implanted and allows 100% successful defibrillation at energy levels of < or = 15 J with right atrial patch configuration.

The beneficial effects of implanted cardioverter defibrillator (ICD) therapy in patients with malignant ventricular tachyarrhythmias and variable degrees of left ventricular (LV) dysfunction are debated. ICD use and patient survival were examined in 128 patients with malignant ventricular arrhythmias and moderate or severe LV dysfunction. Group I included 64 patients with moderate LV dysfunction (LV ejection fraction of > 30%) and group II, 64 patients with severe LV dysfunction (LV ejection fraction of < or = 30%). Follow-up period ranged from 1 to 78 months. The two groups were similar in age, incidence of coronary artery disease and presenting arrhythmia. The mean LV ejection fraction in group I was 44% +/- 8% and group II was 22% +/- 5% (P < 0.0001). At 4 years of follow-up, 66% of patients from group I and 62% from group II (P = NS) had ICD activation for presumed ventricular tachyarrhythmia. Survival was calculated using actuarial analysis. Arrhythmic or sudden death mortality at 4 years of follow-up was 4% in group I and 7% in group II (P = NS). Cardiac mortality was for group I, 7% (P < 0.05), 12% (P < 0.01), 15% (P < 0.01), and 15% (P < 0.01) for follow-up years 1, 2, 3, and 4, respectively. For group II, cardiac mortality was 27%, 36%, 41%, and 41% for follow-up years for 1, 2, 3, and 4, respectively. The majority of cardiac deaths in both groups was observed in the first 2 years of follow-up.(ABSTRACT TRUNCATED AT 250 WORDS)

The quantitative benefit of ICD therapy in patients with malignant ventricular tachyarrhythmia with different degrees of left ventricular dysfunction is unclear. We evaluated patterns of ICD use and survival in 112 patients with moderate to severe left ventricular dysfunction. Group 1 included 57 patients with moderate left ventricular dysfunction (defined as left ventricular ejection fraction greater than 30%) and group 2 comprised 55 patients with severe left ventricular dysfunction (defined as ejection fraction equal to or less than 30%). The follow-up period ranged from 1 to 78 months. Age, incidence of coronary artery disease, and presenting arrhythmia in the two groups were similar. The mean left ventricular ejection fraction in group 1 was 44.6 +/- 8.2% and in group 2 was 21.6 +/- 6% (p < 0.0001). At 3 years of follow-up 65% of the patients in group 1 and 71% in group 2 (p = NS) had ICD activation for presumed ventricular tachycardia. Survival was calculated by means of actuarial analysis. Arrhythmia or sudden death mortality at 4 years of follow-up was 5% in group 1 and 9% in group 2 (NS). Cardiac mortality was higher in patients with severe left ventricular dysfunction reaching levels of statistical significance at 2 years of follow-up. At 2 years of follow-up it was 12% in group 1 and 40% in group 2 (p = 0.05), and at 4 years of follow-up it was 15% in group 1 and 43% in group 2 (p < 0.01). In both groups there was no difference in cardiac mortality in patients who did and did not have appropriate ICD shocks.(ABSTRACT TRUNCATED AT 250 WORDS)

Technological advances in implantable cardioverter defibrillators (ICDs) have provided a variety of programmable parameters and antitachycardia therapies whose utility and impact on clinical outcome is presently unknown. ICDs have capabilities for cardioversion defibrillation alone (first generation ICDs), or in conjunction with demand ventricular pacing (second generation ICDs), or with demand pacing and antitachycardia pacing (third generation ICDs). We examined the pattern of antitachycardia therapy use and long-term survival in 110 patients with sustained ventricular tachycardia (VT) or ventricular fibrillation (VF). Group I included 62 patients with nonprogrammable first generation ICDs that delivered committed shock therapy after ventricular tachyarrhythmia detection based on electrogram rate and/or morphology was satisfied. Group II included 48 patients with multiprogrammable ICDs (including second and third generation ICDs) that had programmable tachyarrhythmia detection based on rate and tachycardia confirmation prior to delivery of electrical treatment with either programmable shocks and/or, as in the third generation ICDs, antitachycardia pacing. Incidence and patterns of antitachycardia therapy use and long-term survival were compared in the two groups. The incidence of appropriate shocks in patients who completed 1 year of follow-up was significantly greater in group I (30 of 43 patients = 70% vs 11 of 26 patients = 42%; P less than 0.05). In the total follow-up period, a significantly larger proportion of group I patients as compared to group II patients used the shock therapies (46 of 62 patients = 74% vs 25 of 48 patients = 52%; P less than 0.01), with the majority doing so within the first year of implantation (96% and 92%, respectively). Although the frequency of antitachycardia therapy activation was similar, the number of shocks delivered per patient was lower in group II, particularly in the initial 3 months of follow-up (P = 0.06). No clinical variable aided in identifying users from nonusers of antitachycardia therapy. Arrhythmic mortality was virtually eliminated in both groups. Two-year actuarial cardiac survival in the two groups was similar (group I = 78% vs group II = 84%; P greater than 0.2). Survival from cardiac mortality in users and nonusers of antitachycardia therapies was also similar in both groups (P greater than 0.2) and in the total patient group (P greater than 0.2). We conclude that programmable ICDs continue to confer advantages in prevention of sudden death that were observed with nonprogrammable ICDs and can be expected to improve patient tolerance and physician acceptance of device therapy for VT/VF.