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Background: Implantable cardioverter defibrillators (ICD) prevent sudden cardiac death (SCD). Patients with end-stage renal disease (ESRD) requiring dialysis are at a very high risk of infection from cardiac implantable electronic device (CIED) implantation as well as mortality. In the present study, we compared the long-term complications and outcomes between subcutaneous ICD (S-ICD) and transvenous ICD (TV-ICD) recipients. Methods: In this retrospective analysis, we analyzed a total of 43 patients with ESRD requiring dialysis who received either a prophylactic S-ICD (26 patients) or a single right ventricular lead TV-ICD (17 patients) at seven experienced centers in Germany. Follow-up was performed bi-annually, at the end of which the data concerning comorbidities and, if applicable, reason for death were checked and confirmed with patients' general practitioner, nephrologist and cardiologist. Results: The median follow up duration was 95.6 months (range 42.8–126.3 months). Baseline characteristics were without noteworthy significant differences between groups. During follow-up (FU), there were significantly more device-associated infections (HR 8.72, 95% confidence interval (CI), 1.18 to 12.85, p < 0.05) and device-associated hospitalizations (HR 10.20, 95% CI 1.22 to 84.61, p < 0.001), as well as a higher cardiovascular mortality (HR 9.17, 95% CI 1.12 to 8.33, p < 0.05), in the TV-ICD group. The number of patients requiring hospitalization for any reason was significantly higher in the TV-ICD group (HR 2.59, 95% CI 1.12 to 6.41, p < 0.05). There was no significant difference in overall mortality (HR 1.92, 95% CI 0.96 to 6.15, p = 0.274). Conclusions: Our data suggest that, in this extended follow-up in seriously compromised renal patients on dialysis, the S-ICD patients have statistically fewer device infections and hospitalizations as well as lower cardiac mortality compared with the TV-ICD cohort. [ABSTRACT FROM AUTHOR]

Introduction: Dual‐coil leads (DC‐leads) were the standard of choice since the first nonthoracotomy implantable cardioverter/defibrillator (ICD). We used contemporary data to determine if DC‐leads offer any advantage over single‐coil leads (SC‐leads), in terms of defibrillation efficacy, safety, clinical outcome, and complication rates. Methods and Results: In the Shockless IMPLant Evaluation study, 2500 patients received a first implanted ICD and were randomized to implantation with or without defibrillation testing. Two thousand and four hundred seventy‐five patients received SC‐coil or DC‐coil leads (SC‐leads in 1025/2475 patients; 41.4%). In patients who underwent defibrillation testing (n = 1204), patients with both lead types were equally likely to achieve an adequate defibrillation safety margin (88.8% vs 91.2%; P = 0.16). There was no overall effect of lead type on the primary study endpoint of "failed appropriate shock or arrhythmic death" (adjusted HR 1.18; 95% CI, 0.86‐1.62; P = 0.300), and on all‐cause mortality (SC‐leads: 5.34%/year; DC‐leads: 5.48%/year; adjusted HR 1.16; 95% CI, 0.94‐1.43; P = 0.168). However, among patients without prior heart failure (HF), and SC‐leads had a significantly higher risk of failed appropriate shock or arrhythmic death (adjusted HR 7.02; 95% CI, 2.41‐20.5). There were no differences in complication rates. Conclusion: In this nonrandomized evaluation, there was no overall difference in defibrillation efficacy, safety, outcome, and complication rates between SC‐leads and DC‐leads. However, DC‐leads were associated with a reduction in the composite of failed appropriate shock or arrhythmic death in the subgroup of non‐HF patients. Considering riskier future lead extraction with DC‐leads, SC‐leads appears to be preferable in the majority of patients. [ABSTRACT FROM AUTHOR]

Background Cardiac contractility modulation (CCM) is an electrical stimulation treatment for symptomatic heart failure (HF) patients. The procedure involves implantation of two ventricular leads for delivery of CCM impulses. The purpose of this study is to compare the efficacy and safety of CCM when the signal is delivered through one vs. two ventricular leads. Methods This prospective blinded randomized trial enrolled 48 patients. Eligible subjects had symptoms despite optimal HF medications, left ventricular ejection fraction <40% and peakVO 2 ≥ 9 ml O 2 /kg/min. All patients received a CCM system with two ventricular leads, and were randomized to CCM active through both or just one ventricular lead; 25 patients were randomized to receive signal delivery through two leads (Group A) and 23 patients to signal delivery through one lead (Group B). The study compared the mean changes from baseline to 6 months follow-up in peakVO 2 , New York Heart Association (NYHA) classification, and quality of life (by MLWHFQ). Results Following 6 months, similar and significant ( p < 0.05) improvements from baseline in NYHA (−0.7 ± 0.5 vs. −0.9 ± 0.7) and MLWHFQ (−14 ± 20 vs. −16 ± 22) were observed in Group A and in Group B. PeakVO 2 showed improvement trends in both groups (0.34 ± 1.52 vs. 0.10 ± 2.21 ml/kg/min; p = ns). No patient died. Serious adverse event rates (20 events in 10 subjects) were not different between groups. No statistically significant difference was found in any of the study endpoints. Conclusions The efficacy and safety of CCM in this study were similar when the signal was delivered through either one or two ventricular leads. These results support the potential use of a single ventricular lead for delivery of CCM. [ABSTRACT FROM AUTHOR]

Background: Atrial fibrillation (AF) is a multifactorial disease of the atria. Objective: We studied the differences in the atrial autonomic innervation pattern in subjects with AF compared with sinus rhythm (SR). Methods: Preparation of postmortem isolated hearts of subjects with documented persistent AF (group A) and SR (group B) included: (1) histological sectioning of predefined areas and quantification of nerve density, and (2) differentiation using immunohistochemistry in adrenergic (sympathetic, tyrosine-hydroxylase antibody), cholinergic (parasympathetic, choline-acetyltransferase antibody) and mixed (adrenergic and cholinergic staining) nerves. Results: Characteristics of subjects in group A (N = 15) and group B (N = 24) did not differ. The mean overall nerve density was similar between groups (A: 0.31 ± 0.25/mm2; B: 0.35 ± 0.25/mm2; P = .87). Nerve density appeared higher in the region of the pulmonary vein ostia and antrum (group A: 0.38 ± 0.21/mm2; group B: 0.32 ± 0.19/mm2,) compared with other locations of the right and left atrium. A total of 2,224 (group A: 685; group B: 1539) nerves were differentiated using immunohistochemistry. There was a high degree of colocalization of adrenergic and cholinergic nerves (group A: 80% mixed staining, group B: 69% mixed staining). In group A hearts there was a significantly lower density of predominantly cholinergic nerves (0.025 ± 0.052/mm2 vs. 0.058 ± 0.099/mm2; P = .008) and a higher density of nerves containing adrenergic components (0.24 ± 0.18/mm2 vs. 0.18 ± 0.17/mm2, P = .046). Conclusion: Overall autonomic nerve density did not differ between atria with persistent AF compared with SR. On a morphological level, we detected a shift toward a lower density of cholinergic nerves and a higher density of nerves containing adrenergic components in AF subjects. [ABSTRACT FROM AUTHOR]

Cardiac resynchronization therapy has been shown to be an effective treatment for patients with systolic ventricular dysfunction, prolonged (>120 ms) QRS duration, and New York Heart Association (NYHA) functional class III or IV symptoms despite optimal medical therapy. However, studies show that a majority of heart failure patients have QRS duration <120 ms. We have been investigating the potential utility of cardiac contractility modulating (CCM) signals as a treatment option for such patients. Cardiac contractility modulating signals are non-excitatory signals applied during the absolute refractory period using a pacemaker-like device that connects to the heart with pacemaker leads. Acute studies carried out in animals and humans with heart failure suggest that CCM signals can enhance the strength of left ventricular contraction. Results of initial long-term studies designed mainly to demonstrate feasibility and provide preliminary indication of safety in patients with medically refractory NYHA functional class III heart failure are summarized. The results of these preclinical and clinical studies formed the basis for proceeding with two prospective, randomized clinical studies currently underway to definitively test the safety and efficacy of this treatment. [Copyright &y& Elsevier]

Aims This study was undertaken to evaluate if a history of episodes of atrial fibrillation (AF) has an effect on survival in patients (pts) with implanted cardioverter defibrillators (ICD). Methods and results Retrospective analysis of baseline characteristics, medication and endpoints in pts receiving a dual-chamber ICD comparing pts without (group 1: n=291) and with a history of AF (group 2: n=68). Conclusion ICD-patients with a history of AF had a higher than average risk of death early after implantation and after device-detected episodes of AF. [ABSTRACT FROM PUBLISHER]

BACKGROUND: Many different stent types are available for intracoronary placement. No clinical trial has demonstrated clearly the superiority of any stent design over another. METHODS: This study was designed to analyze clinical and angiographic results after using intracoronary PURA-VARIO (Devon Medical, Hamburg, Germany) (PUVA) stents. A total of 306 implanted stents were investigated in a series of 217 unselected patients (61.2 ± 10.7 years, 74.3% male). Stenting was performed electively and during acute coronary syndromes. Stents were manually mounted on angioplasty balloons and expanded in the target lesion. Angiographic measurements were carried out by quantitative coronary angiography. RESULTS: Stenting was successful in 214/217 patients (98.8%). During hospitalization (median three days) 206 patients (94.9%) were free from adverse cardiac events. Stent thrombosis occurred in five patients (2.3%), Q-wave infarction in one (0.5%) and urgent percutaneous target vessel revascularization in four (1.8%). Follow-up angiography, performed in 170 patients (78.3%) showed a restenosis (≥50% diameter stenosis) in 44/170 patients (25.9%), requiring angioplasty in 29 (17.2%). A surgical revascularization was recommended in 13 patients (7.6%). One patient died during follow-up from an unknown cause; however, sudden cardiac death was most likely. CONCLUSIONS: PUVA stents are characterized by a high level of safety and efficacy. Clinical and angiographic results are comparable with those of other approved stents. (Int J Cardiovasc Intervent 2003; 5: 156-160) [ABSTRACT FROM AUTHOR]

Introduction: Patients with bradycardia requiring permanent pacing frequently suffer from additional atrial tachyarrhythmias (ATs). This study evaluated the safety and efficacy of atrial antitachycardia pacing (ATP) and the performance of pacing for AT prevention implemented into a new pacemaker. Methods and Results: In patients with conventional indications for permanent pacing, an investigational DDDRP pacemaker (Medtronic AT500, model 7253) was implanted. The primary study objectives were to determine the safety of overall device functioning and its efficacy in terminating spontaneous AT. A secondary endpoint was to determine the reliability of AT detection. Pacemaker memory functions were used to analyze the impact of dedicated pacing algorithms on AT prevention. In 33 European and Canadian centers, 325 patients were enrolled (mean follow-up 2.3 ± 1.3 months). Complication-free survival at 3 months was 88%. In 2,145 episodes stored with atrial electrograms, AT detection was confirmed in 97%. The algorithm for continuous overdrive pacing increased the percentage of atrial pacing to 97%. After ATP activation, 16,683 of 52,468 AT episodes were treated (120 patients). Of these, 8,903 episodes (53%) were terminated successfully by ATP. No proarrhythmic effect of preventive pacing or atrial ATP was observed. Preventive pacing algorithms increased the median percentage of atrial pacing from 62% to 97%. However, the number of AT/AF (atrial fibrillation) episodes (4.1 vs 4.1 per patient per day) and the time in AT/AF (13.7% vs 12.8%) was not significantly different before and after activation of preventive pacing. Conclusion: DDDRP pacing with a new system for AT therapy was safe and associated with successful pace-termination of AT in 53% of episodes. Preventive pacing and atrial ATP algorithms represent two new functions that can be implemented safely into pacemaker systems for nonpharmacologic treatment of ATs in patients requiring pacemaker therapy. [ABSTRACT FROM AUTHOR]