Time Of Device Implantation Research Articles

Pacemaker malfunction due to mechanical failure of the lead–header interface

An 8 year old female spayed Boxer dog, diagnosed with concurrent vasovagal syncope and arrhythmogenic right ventricular cardiomyopathy, presented for routine evaluation approximately three months following epicardial pacemaker implantation. Routine device interrogation revealed intermittent loss of ventricular capture and intermittent failure to appropriately sense. Following evaluation of chronic impedance data, failure of the pacemaker lead–header interface or lead conductor fracture was suspected. Radiographic and pacemaker interrogator findings suggested incomplete lead insertion into the device header with intermittent loss of ventricular capture and variable pacemaker sensing. We hypothesize that either the presence of a loose or cross-threaded set screw or operator error at the time of device implantation may have caused this complication. This report details the diagnosis of mechanical failure of the lead–header interface, a complication not previously reported in a veterinary patient.

Clopidogrel Increases Bleeding Complications in Patients Undergoing Heart Rhythm Device Procedures

Management of antiplatelet therapy at the time of device implantation remains controversial. This study aimed to assess the risk of bleeding complications in patients receiving clopidogrel at the time of cardiac device surgery. We performed a retrospective case-control study. Between 2004 and 2010, 101 consecutive patients receiving clopidogrel underwent cardiac device surgery (pacemaker or implantable cardioverter-defibrillator implantation, and generator replacement) in our institution. Controls were 1:1 matched on age, sex, device, type of procedure, number of leads implanted, and venous approach (cephalic or subclavian). A significant bleeding complication was defined as pocket hematoma requiring surgical evacuation or prolonged hospitalization, hemothorax, pericardial effusion, or tamponade. Bleeding complications occurred more frequently in patients receiving clopidogrel at the time of device procedure: 11.9% versus 4.0% (P = 0.037; odds radio [OR] 3.27 [1.02-10.5]). Significant bleeding complications were noted in 12 patients (11.9%) receiving clopidogrel, including two patients with pericardial effusion and one patient with hemothorax. Four controls (4.0%) had bleeding complications (three pocket hematomas and one pericardial effusion). The single factor associated with increased bleeding complications in patients receiving clopidogrel was subclavian puncture (P = 0.008). In the entire cohort (n = 202), multivariate analysis identified two independent predictors of significant bleeding complications: clopidogrel treatment at the time of surgery (P = 0.03; OR 3.7 [1.1-12.6]) and subclavian venous puncture (P = 0.03; OR 3.44 [1.1-10.4]). Clopidogrel treatment at the time of heart rhythm device procedures is associated with an increased risk of significant bleeding complications. Subclavian puncture seems to strongly increase hemorrhagic complications in this setting.

Inappropriate Therapy Delivered by a CRT‐D for Tachycardia with Simultaneous Atrial and Ventricular Activation: What Is the Tachycardia?

A 69-year-old woman was admitted to our hospital after she had received several shocks without warning from a model C154DWK ConcertoTM cardiac resynchronization therapy + defibrillation (CRT-D; Medtronic Inc., Minneapolis, MN, USA), implanted 2 years earlier for management of sustained ventricular tachycardia (VT) and congestive heart failure due to dilated cardiomyopathy. At the time of device implantation, the sensing and pacing characteristics of a tined atrial lead placed in the right atrial appendage were within normal limits. Interrogation of the device retrieved several episodes of tachycardia, unsuccessfully treated by antitachycardia pacing (Fig. 1A), followed by a successful direct cardioversion shock. Recordings stored in the device memory during VT revealed regular, nearly simultaneous ventricular and atrial electrograms (Fig. 1A). The 12-lead electrocardiogram during AAI pacing by the device revealed a marked latency between the pacing spike and the P-wave and a normal PQ interval (Fig. 1B). What is the mechanism of this tachycardia?

Left Ventricular Lead Position and Clinical Outcome in the Multicenter Automatic Defibrillator Implantation Trial–Cardiac Resynchronization Therapy (MADIT-CRT) Trial

An important determinant of successful cardiac resynchronization therapy for heart failure is the position of the left ventricular (LV) pacing lead. The aim of this study was to analyze the impact of the LV lead position on outcome in patients randomized to cardiac resynchronization-defibrillation in the Multicenter Automatic Defibrillator Implantation Trial-Cardiac Resynchronization Therapy (MADIT-CRT) study. The location of the LV lead was assessed by means of coronary venograms and chest x-rays recorded at the time of device implantation. The LV lead location was classified along the short axis into an anterior, lateral, or posterior position and along the long axis into a basal, midventricular, or apical region. The primary end point of MADIT-CRT was heart failure (HF) hospitalization or death, whichever came first. The LV lead position was assessed in 799 patients, (55% patients ≥65 years of age, 26% female, 10% LV ejection fraction ≤25%, 55% ischemic cardiomyopathy, and 71% left bundle-branch block) with a follow-up of 29±11 months. The extent of cardiac resynchronization therapy benefit was similar for leads in the anterior, lateral, or posterior position (P=0.652). The apical lead location compared with leads located in the nonapical position (basal or midventricular region) was associated with a significantly increased risk for heart failure/death (hazard ratio=1.72; 95% confidence interval, 1.09 to 2.71; P=0.019) after adjustment for the clinical covariates. The apical lead position was also associated with an increased risk for death (hazard ratio=2.91; 95% confidence interval, 1.42 to 5.97; P=0.004). LV leads positioned in the apical region were associated with an unfavorable outcome, suggesting that this lead location should be avoided in cardiac resynchronization therapy. Clinical Trial Registration- URL: http://clinicaltrials.gov. Unique identifier: NCT00180271.

Mortality benefits from implantable cardioverter-defibrillator therapy are not restricted to patients with remote myocardial infarction

There is little debate over the life-saving properties of implantable cardioverter-defibrillators (ICDs) in select patient populations. Mortality benefits in patients who have survived cardiac arrest or who are at risk for sudden cardiac arrest is established. In particular, the recognized improved survival in patients with depressed ejection fraction after myocardial infarction (MI) has resulted in a dramatic increase in ICD implants. 1 Bardy G.H. Lee K.L. Mark D.B. et al. Amiodarone or an implantable cardioverter-defibrillator for congestive heart failure. N Engl J Med. 2005; 352: 225-237 Crossref PubMed Scopus (5242) Google Scholar Despite overwhelming evidence of the clinical utility of ICDs in primary prevention of sudden cardiac death (SCD), patient selection and timing of device implantation continues to be the subject of much debate. Mortality benefits from implantable cardioverter-defibrillator therapy are not restricted to patients with remote myocardial infarction: an analysis from the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT)Heart RhythmVol. 8Issue 3PreviewThe implantable cardioverter-defibrillator (ICD) is an effective therapy for preventing sudden cardiac death (SCD) in patients with prior myocardial infarction (MI) and reduced left ventricular function; however, the optimal timing of ICD implantation after MI remains unknown. Full-Text PDF

Prognostic Significance of J Wave in Patients Who Underwent Device Therapy for Ventricular Defibrillation

Background: J wave has been reported to be associated with higher incidences of life-threatening events in patients with either structural or nonstructural heart disease. The risk of J wave in patients who implanted a defibrillator with/without cardiac-resynchronization therapy device is unclear.Methods: The relationship between J-wave appearance and defibrillator interventions was evaluated by analyzing electrograms stored in devices retrospectively with proportional hazards models.Results: A total of 150 patients were enrolled and followed for a mean period of 38.8±25.0 months. Underlying heart diseases for device implantation were: myocardial infarction in 40; dilated cardiomyopathy in 30; hypertrophic cardiomyopathy in 16; ARVC in 3; Brugada syndrome in 22; idiopathic VF in 13; and others in 26 patients. Of these, 30 patients (20.0%) showed J wave at the time of implant. Patients with J wave had higher incidences of device intervention for VT/VF than those without (56.7% vs. 35.8%; P=0.0390). Multivariate analysys revealed that J-wave appearance and documented VT were independently associated with life-threatening events in patients with device implantation, even after the adjustment of age, gender, and left ventricular ejection fraction (HR, 2.20; 95% CI, 1.14–4.06; P=0.0193 and HR, 4.13; 95% CI, 2.15–8.46; P<0.0001, respectively).Conclusion: J wave at the time of device implantation identifies the risk of future device interventions.

Renal function and mortality following cardiac resynchronization therapy

Cardiac resynchronization therapy (CRT) improves outcomes in heart failure, yet selection of patients likely to have survival benefit is problematic. Chronic kidney disease (CKD) is an important determinant of mortality in patients with congestive heart failure therefore we sought to determine the impact of CKD on mortality benefit after CRT. All CRT device implantations in patients not on dialysis at Mayo Clinic between January 1999 and December 2005 were included. Of 482 patients, 342 (71%) had CKD (defined as a glomerular filtration rate (GFR) of ≤60 mL/min/1.73 m(2)) at the time of device implantation. Patients with CKD were older (71 ± 10 vs. 63 ± 14 years, P < 0.01) than patients without CKD, and more often anaemic (12.70 ± 1.73 vs. 13.24 mg/L, P < 0.01), with similar ejection fraction (22 ± 8 vs. 23 ± 8%, P = 0.32). Survival was superior in patients with normal or mild renal dysfunction compared with patients with CKD (72 vs. 57% at 3 years, P < 0.01). After multivariate analysis, CKD remained a significant predictor of poor survival following CRT. Chronic kidney disease is common in patients undergoing CRT and associated with a higher mortality and should be considered when evaluating patients for CRT.

Ventricular Assist Device in Patients With Prosthetic Heart Valves

Ventricular assist device (VAD) support inpatients with a prosthetic heart valve had previously been considered a relative contraindication due to an increased risk of thromboembolic complications. We report our clinical experience of VAD implantation in patients with prosthetic heart valves, including both mechanical and bioprosthetic valves. The clinical records of 133 consecutive patients who underwent VAD implantation at a single institution from January 2002 through June 2009 were retrospectively reviewed. Six of these patients had a prosthetic valve in place at the time of device implantation. Patient demographics,operative characteristics, and postoperative complications were reviewed.Of the six patients,four were male.The mean age was 57.8 years (range 35–66 years). The various prosthetic cardiac valves included a mechanical aortic valve (n = 2), a bioprosthetic aortic valve (n = 3), and a mechanical mitral valve (n = 1).The indications for VAD support included bridge to transplantation (n = 2), bridge to recovery (n = 1), and postcardiotomy ventricular failure(n = 3). Three patients underwent left ventricular assist device placement and three received a right ventricular assist device. Postoperatively, standard anticoagulation management began with a heparin infusion (if possible)followed by oral anticoagulation.The 30-day mortality was50% (3/6). The mean duration of support among survivors was 194.3 days (range 7–369 days) compared with 16.0 days(range 4–29 days) for nonsurvivors. Of the three survivors,two were successfully bridged to heart transplantation and one recovered native ventricular function.Among the three nonsurvivors,acute renal failure developed in each case, and two developed heparin-induced thrombocytopenia. This study suggests that VAD placement in patients with a prosthethic heart valve, either mechanical or bioprosthetic,appears to be a reasonable option.

Chronic kidney disease is an independent predictor of pocket hematoma after pacemaker and defibrillator implantation

The aim of this investigation was to determine additional predisposing factors of pocket hematoma formation in patients undergoing anti-arrhythmic device surgery. Initially, we performed a retrospective chart review of 459 patients on warfarin therapy who underwent anti-arrhythmic device surgery (pacemaker or defibrillator implantation, generator replacement, or lead revision) between April 2004 and September 2008 to determine whether continuation of anticoagulation or cessation of anticoagulation, with or without bridging therapy, was the preferred approach. In those patients who developed pocket hematoma, we then analyzed factors that might predispose to hematoma formation. The incidence of pocket hematoma in the entire group was 2.2% (n = 10). Forty-eight percent of the patient group was on continued warfarin (n = 220), 27% on bridging therapy with intravenous heparin or subcutaneous enoxaparin (n = 123) and 66% were on antiplatelet therapy (aspirin or clopidegrol or both; n = 303) at the time of device implantation. Twelve percent of the patients had chronic kidney disease (n = 55). In multivariate regression analysis, after adjusting for anticoagulation and antiplatelet agents, chronic kidney disease was found to be a significant risk factor for pocket hematoma formation after ICD and pacemaker placement. An increase of 1.0mg/dl in creatinine levels was associated with a nearly twofold increase in hematoma formation (OR, 1.99; 95% CI, 1.22-3.21; p = 0.03). Chronic kidney disease is a significant risk factor for pocket hematoma formation after pacemaker and ICD placement, independent of anticoagulation and antiplatelet agents.

Relationship between left ventricular stimulation characteristics at implantation and echocardiographic response after 6 months of cardiac resynchronization therapy

Although the electrical stimulation of an ischaemic tissue adversely affects the left ventricular (LV) systolic function, the optimal stimulation site in patients with non-ischaemic cardiomyopathy has not been systematically studied. We hypothesized that the local stimulation characteristics at the time of device implantation predict the response to cardiac resynchronization therapy (CRT). We measured the impedance, sensing, and capture threshold of a bipolar LV lead in 138 patients with non-ischaemic cardiomyopathy undergoing first implantation of CRT device for drug refractory heart failure. All patients underwent echocardiography at baseline and at 6 months post-implantation. An absence of favourable response to CRT was defined as <15% decrease in echocardiographic LV end-systolic volume (LVESV) at 6 months. Echocardiographic response to CRT was observed in 70% of patients. The LV lead measurements predicted neither the optimal stimulation site nor the response to CRT. Left ventricular capture threshold (1.50 ± 1.1 vs. 1.32 ± 0.8 V) and impedance (725 ± 287 vs. 720 ± 261 Ω) were similar between the responders and the non-responders. Independent of baseline LV ejection fraction or ESV, the LV R-wave amplitude at implantation was significantly higher (P = 0.0038) in responders (12.7 ± 5.2 mV) than in non-responders (9.7 ± 6.3 mV), with an area under the receiver operating characteristic curve of 0.7. Response to CRT, as determined by decrease in LVESV at 6 months, was associated with significantly higher LV R-wave amplitude at the time of device implantation.

Dual Antiplatelet Therapy and Heparin “Bridging” Significantly Increase the Risk of Bleeding Complications After Pacemaker or Implantable Cardioverter-Defibrillator Device Implantation

This study was designed to assess the risk of significant bleeding complications in patients receiving antiplatelet or anticoagulation medications at the time of implantable cardioverter-defibrillator (ICD) device implantation. Periprocedural management of antiplatelet or anticoagulation therapy at the time of device implantation remains controversial. We performed a retrospective chart review of bleeding complications in all patients undergoing ICD or pacemaker implantation from August 2004 to August 2007. Aspirin or clopidogrel use was defined as taken within 5 days of the procedure. A significant bleeding complication was defined as need for pocket exploration or blood transfusion; hematoma requiring pressure dressing or change in anticoagulation therapy; or prolonged hospitalization. Of the 1,388 device implantations, 71 had bleeding complications (5.1%). Compared with controls not taking antiplatelet agents (n = 255), the combination of aspirin and clopidogrel (n = 139) significantly increased bleeding risk (7.2% vs. 1.6%; p = 0.004). In patients taking aspirin alone (n = 536), bleeding risk was marginally higher than it was for patients taking no antiplatelet agents (3.9% vs. 1.6%, p = 0.078). The use of periprocedural heparin (n = 154) markedly increased risk of bleeding when compared with holding warfarin until the international normalized ratio (INR) was normal (n = 258; 14.3% vs. 4.3%; p < 0.001) and compared with patients receiving no anticoagulation therapy (14.3% vs.1.6%; p < 0.0001). There was no statistical difference in bleeding risk between patients continued on warfarin with an INR > or =1.5 (n = 46) and patients who had warfarin withheld until the INR was normal (n = 258; 6.5% vs. 4.3%; p = 0.50). Dual antiplatelet therapy and periprocedural heparin significantly increase the risk of bleeding complications at the time of pacemaker or ICD implantation.

Percutaneous mitral valve repair with the MitraClip system: acute results from a real world setting

AimsThis study sought to evaluate the feasibility and early outcomes of a percutaneous edge-to-edge repair approach for mitral valve regurgitation with the MitraClip® system (Evalve, Inc., Menlo Park, CA, USA).Methods and resultsPatients were selected for the procedure based on the consensus of a multidisciplinary team. The primary efficacy endpoint was acute device success defined as clip placement with reduction of mitral regurgitation to ≤2+. The primary acute safety endpoint was 30-day freedom from major adverse events, defined as the composite of death, myocardial infarction, non-elective cardiac surgery for adverse events, renal failure, transfusion of >2 units of blood, ventilation for >48 h, deep wound infection, septicaemia, and new onset of atrial fibrillation. Thirty-one patients (median age 71, male 81%) were treated between August 2008 and July 2009. Eighteen patients (58%) presented with functional disease and 13 patients (42%) presented with organic degenerative disease. A clip was successfully implanted in 19 patients (61%) and two clips in 12 patients (39%). The median device implantation time was 80 min. At 30 days, there was an intra-procedural cardiac tamponade and a non-cardiac death, resulting in a primary safety endpoint of 93.6% [95% confidence interval (CI) 77.2–98.9]. Acute device success was observed in 96.8% of patients (95% CI 81.5–99.8). Compared with baseline, left ventricular diameters, diastolic left ventricular volume, diastolic annular septal–lateral dimension, and mitral valve area significantly diminished at 30 days.ConclusionOur initial results with the MitraClip device in a very small number of patients indicate that percutaneous edge-to-edge mitral valve repair is feasible and may be accomplished with favourable short-term safety and efficacy results.

The Relationship between Warfarin, Aspirin, and Clopidogrel Continuation in the Peri-procedural Period and the Incidence of Hematoma Formation after Device Implantation

Many patients requiring permanent pacemaker (PPM) or implantable cardiac defibrillator (ICD) placement are anticoagulated with warfarin, aspirin (ASA), and clopidogrel for a number of thromboembolic risk indications. The present review sought to evaluate the relationship between continuation of these medications in the peri-procedural period and the incidence of hematoma formation after implantation. We retrospectively reviewed consecutive patients undergoing PPM and ICD implantation at our hospital from January 2007-2009. All patients on warfarin, aspirin, and clopidogrel were maintained on these medications peri-operatively. We collected data on the use of warfarin at implantation, INR prior to device implantation, use of dual-antiplatelet therapy (DAPT), such as concomitant aspirin and clopidogrel and subsequent formation of hematoma in the peri-procedure period. PPM and ICD implantations were performed in 194 men and six women. The mean age was 73 years old. Fifty eight patients were taking warfarin with an average international normalized ratio of 1.9 +/- 0.6; 112 were on ASA, 23 on clopidogrel, and 20 of them on DAPT. Only five patients were on DAPT and warfarin combined at the time of device implantation. Hematomas formed in a total of seven patients (3.5%), five of whom were on DAPT consisting of ASA and clopidogrel (P < 0.0001) while only two of them were on warfarin (P = 0.67). Pocket revision for hematoma evacuation was needed in four patients (2%), three of whom were on DAPT and only one on warfarin. This study suggests that hematoma formation after PPM or ICD implantation is rare, even among those who are anticoagulated. There were more patients with hematoma on DAPT than warfarin therapy and half of these patients with this complication needed pocket revision for evacuation. (PACE 2010; 385-388).

213 Does continuous assessment of heart rate variability by devices provide prognostic information in cardiac resynchronization therapy patients?

Heart failure remains a severe disease with high mortality despite pharmologic treatment and new successful therapy options such as cardiac resynchronization therapy (CRT). Heart rate variability (HRV), which reflects autonomic nervous system function, is a prognostic marker in chronic heart failure. It can be easily and continuously assessed by CRT devices but its prognostic value is not well known in these patients. The relationship between HRV and morbimortality was examined in a retrospective study concerning 34 patients who received CRT devices between july 2002 and february 2008. HRV footprint and standard deviation of averaged normal R to R intervals (SDANN) was continuously measured by devices. The study showed an overall improvement in SDANN (71,8 ± 18,3 to 87,6 ± 29 ms, p=0,002) and HRV footprint (33,5 ± 9,2 to 37,5 ± 9%, p=0,013) after resynchronization. During a median of 17,7 months of follow up, 26% (9/34) patients died or were hospitalised for acute heart failure. SDANN and HRV foorprint at the time of device implantation were not predictors of morbimortality. Improvement of SDANN > 5% after resynchronization was predictor of survival free from event (p<0,0001). Continuous assessment of SDANN by devices may be a useful tool for risk stratification in CRT patients.

Determinants and clinical significance of persistent residual shunting in patients with percutaneous patent foramen ovale closure devices

Background Percutaneous patent foramen closure has emerged as a dynamic therapy for stroke prevention secondary to paradoxical embolism. Recent reports, however, have documented uncertain clinical efficacy and patients with incomplete PFO closure may remain at risk of recurrent events. We sought to identify echocardiographic determinants and the clinical significance of persistent residual shunting after percutaneous PFO closure. Methods From 2002 to 2008, 51 consecutive patients with recurrent stroke ( n = 46) or transient ischemic attack (TIA) ( n = 5) underwent percutaneous PFO closure at a tertiary care hospital. PFO size, degree of shunt, tunnel length, and atrial septal aneurysm geometry were documented at the time of device implantation. All patients received follow-up with transesophageal ( n = 43) or transthoracic ( n = 8) echocardiography 6.7 ± 2 months post procedure and presence of residual shunting and recurrent stroke/TIA were recorded. Results All patients underwent percutaneous PFO closure without complication. Ten patients (20%) demonstrated residual right-to-left shunting at the time of follow-up: color Doppler (2), mild ( n = 3), moderate ( n = 2) and severe ( n = 3). Univariate analysis revealed larger PFO size ( F = 4.71, p = 0.036) as the only independent predictor of residual shunting after PFO closure. Ninety six percent of patients remained stroke and TIA free 3 years ± 8 months post closure, with no clinical differences between the two groups. Conclusions In patients undergoing percutaneous PFO closure for stroke or TIA, a larger PFO size predisposes to residual shunting approximately 6 months post PFO closure, but with no short term increased risk of recurrent thromboembolic events.

Review of the ICD Registry's Third Year, Expansion to include Lead Data and Pediatric ICD Procedures, and Role for Measuring Performance

ntroduction he National ICD Registry became the sole repository of CD implantation data for Medicare beneficiaries on April , 2006, and as of June 2009 had collected data from ,432 hospitals in the United States totaling over 380,000 mplants. The registry was developed through a partnership f the Heart Rhythm Society (HRS [www.HRSonline.org]) nd the American College of Cardiology Foundation ACCF [www.acc.org]) utilizing the expertise of the ational Cardiovascular Data Registry (NCDR [www. ccncdr.com]) and has made substantial progress toward everal predefined goals:

457 Gastric Pacing Can Eliminate Dependency On Supplemental Nutrition and Improve Medically Refractory Gastroparesis

INTRODUCTION: Gastric stimulation has been shown to improve the symptoms of medically refractory gastroparesis. With enough symptomatic improvement, patients should be able to decrease or eliminate their dependency on supplemental nutrition (parenteral or enteral) in the post-operative period. MATERIALS AND METHODS: This is a review of a single surgeons operative experience from 9/02 to 7/08. Patients with a diagnosis of diabetic or idiopathic gastroparesis that had a gastric pacer placed were selected for analysis. Chart review included age, gender, weight, symptom improvement, and the requirement of additional nutritional supplementation at baseline, six, and 12 months. RESULTS: Fifty-two patients had interrogation and programming of the gastric pacer (Enterra) at time of implantation. As part of follow-up, patients were assessed for symptom improvement and were adjusted appropriately if no improvement was seen. Patients included eight males and 44 females. The average age was 38 years (range 20-87). Thirty-one had a pre-operative, 6 month, and 12 month weight recording. Average weight was 151.9 lbs, 153.2 lbs, and 155.1 lbs at those respective times. In 47 patients with a mean follow-up of 19 months, 34 (72%) reported improvement in symptoms, nine (19%) reported no improvement in symptoms, and four had initial resolution of symptoms but return to baseline at last followup. Preoperatively, 10 patients were receiving jejunal feeds (TF) and two were receiving total parenteral nutrition (TPN). Subsequently after device implantation, seven patients at six months and an additional three at one year were off all forms of supplementation and receiving nutrition solely by mouth. No statistically significant weight change was seen in this group. Seven patients had a jejunostomy tube placed at the time of device implantation for subsequent enteral feeds. Three patients at six months had enteral feedings stopped and the remaining four continued tube feeds at one year. No patient in this group had an infectious complication secondary to concomitant gastric stimulator and jejunal tube placement. One Enterra system was replaced due to device malfunction, two revised secondary to generator malposition, and one removed due to lead erosion. CONCLUSIONS: The majority of patients demonstrated weight stability after gastric pacer placement. 72% of patients reported improvement in symptoms. Patients receiving supplemental nutrition preoperatively showed decreased reliance on enteral feeds or TPN after gastric stimulation. Concomitant jejunal tube and gastric pacer placement did not demonstrate a higher infectious complication rate.

Ventricular Assist Devices: History, Patient Selection, and Timing of Therapy

Timing of therapy and selection of patients in the use of ventricular assist devices (VADs) can be difficult. In general, consideration for VAD implantation is appropriate in patients with endstage heart failure who are failing optimal medical therapy and in whom no alternative traditional surgical treatment options are available. However, identifying when a particular patient has reached this point is not always straightforward. There are a broad range of medical and surgical therapies for patients with overt heart failure, and this armamentarium is constantly expanding. The risks, benefits, and expected outcomes with VAD therapy have also undergone dramatic changes over the last decade. Advances in technology have led to a proliferation of newer generation devices that are smaller, lighter, easier to implant, and more reliable than previous generation devices. This, in turn, has led to a markedly improved risk-benefit ratio, with increased durability and reduced morbidity. The indications for the implantation of ventricular assist devices have also evolved over the last several years, and specific patient presentations and goals of therapy have led to specific indications. Device therapy has traditionally been classified as bridge to recovery, bridge to transplantation, and destination therapy. However, such designations may not be well defined at the time of implantation, and recovery and response following initiation of VAD support may allow patients to change from one classification to another. The current data regarding indications and timing of device implantation are reviewed.

Review of the Registry's Second Year, Data Collected, and Plans to Add Lead and Pediatric ICD Procedures

esenc F d m l b t G t N d s Q o M N h a c p i t t i e r i e t a e y p c e t t b T t ntroduction he National ICD Registry became the sole repository of CD implantation data for Medicare beneficiaries April 1, 006 and as of June 2008 had collected data from 1,448 ospitals in the United States totaling over 270,373 imlants. This registry was developed through a partnership of he Heart Rhythm Society (HRS; www.HRSonline.org) and he American College of Cardiology Foundation (ACCF; ww.acc.org) utilizing the expertise of the National C iovascular Data Registry (NCDR; www.accncdr.com). he National ICD Registry is accruing ICD implants at the ate of 10,000 per month with 88% of implants being done n hospitals that enter all patients receiving ICDs including oth primary and secondary prevention indications in all ge groups. A rigorous Data Quality Reporting process is in lace to ensure data accuracy and hospital auditing will egin the summer of 2008. Six abstracts have been pr ed, and four manuscripts are in development utilizing ata generated from the National ICD Registry answering ey clinical questions elicited from the growing ICD imlant patient database ( http://www.accncdr.com). Funding or the Longitudinal ICD Registry Study has been procured, nd the study will begin in 2008. The scope of the National CD registry is being expanded to include data on new trial, ventricular, defibrillation, and left-heart leads placed t the time of ICD implant and whenever existing leads are epositioned, replaced, extracted or abandoned. These data ill assist the Food and Drug Administration (FDA) with urveillance of lead performance. Pediatric ICD implantaions will be followed in the Registry; and the Registry is eing positioned to serve as a performance reporting tool to ssist with quality measures.

A randomized comparison of defibrillation thresholds in the right ventricular outflow tract versus right ventricular apex

To determine whether the placement of an implantable cardioverter-defibrillator (ICD) lead in the right ventricular outflow tract (RVOT) has the same defibrillation threshold (DFT) as the right ventricular apex (RVA). Right ventricular ICD leads have usually been placed in the RVA. Development of active fixation technology has allowed the placement of these leads in alternate locations such as the RVOT. At time of device implantation, 26 patients with either ischemic or dilated cardiomyopathy underwent DFT testing in both the RVA and RVOT using a binary search algorithm. Placement of the lead in the RVA had a mean DFT of 7.6 +/- 2.8 J while the placement of the lead in the RVOT had a mean DFT of 10.3 +/- 3.0 J. The median (25th and 75th percentiles) DFTs in the RVA and RVOT were 7.5 J (6 and 11 J) and 11 J (9 and 14 J), respectively (p = 0.0002). Placement of the right ventricular lead in the RVA has a significantly lower DFT than placement of the lead in the RVOT.