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Background Atrioventricular (AV)-synchronous single-chamber leadless pacing using a mechanical atrial sensing algorithm produced high AV synchrony in clinical trials, but clinical practice experience with these devices has not yet been described. Objective To describe pacing outcomes and programming changes with AV-synchronous leadless pacemakers in clinical practice. Methods Consecutive patients without persistent atrial fibrillation who received an AV-synchronous leadless pacemaker and completed follow-up between February 2020 and April 2021 were included. We evaluated tracking index (atrial mechanical sense followed by ventricular pace [AM-VP] divided by total VP), total AV synchrony (sum of AM-ventricular sense [AM-VS], AM-VP, and AV conduction mode switch), use of programming optimization, and improvement in AV synchrony after optimization. Results Fifty patients met the inclusion criteria. Mean age was 69 ± 16.8 years, 24 (48%) were women, 24 (48%) had complete heart block, and 17 (34%) required ≥50% pacing. Mean tracking index was 41% ± 34%. Thirty-five patients (70%) received ≥1 programming change. In 36 patients with 2 follow-up visits, tracking improved by +9% ± 28% (P value for improvement = .09) and +18% ± 19% (P = .02) among 15 patients with complete heart block. Average total AV synchrony increased from 89% [67%, 99%] to 93% [78%, 100%] in all patients (P = .22), from 86% [52%, 98%] to 97% [82%, 99%] in those with complete heart block (P = .04), and from 73% [52%, 80%] to 78% [70%, 85%] in those with ≥50% pacing (P = .09). Conclusion In patients with AV-synchronous leadless pacemakers, programming changes are frequent and are associated with increased atrial tracking and increased AV synchrony in patients with complete heart block., Graphical abstract

This study sought to determine the indications, characteristics, and outcomes of cardiovascular implantable electronic device (CIED) surgery in patients with LVAD.Many patients with a left ventricular assist device (LVAD) will require implantable cardioverter-defibrillator generator change or device revision or are candidates for de novo implantable cardioverter-defibrillator implantation following LVAD implantation.We performed an observational retrospective study of all LVAD recipients who subsequently underwent CIED surgery at Duke University Hospital from 2009 to 2019.A total of 159 patients underwent CIED surgery following LVAD implantation, including generator change (n = 93), device revision (n = 38), and de novo implant (n = 28). The median (interquartile range) time from LVAD implantation to CIED surgery was 18.1 months (5.5 to 35.1 months). Pre-operative risk for infection was elevated in the overall cohort with a median (interquartile range) Prevention of Arrhythmia Device Infection Trial (PADIT) score of 7.0 (5.0 to 9.0). Pocket hematoma occurred in 21 patients (13.2%) following CIED surgery. Antimicrobial envelops were used in 43 patients (27%). Device infection due to CIED surgery occurred in 5 (3.1%) patients and occurred only in patients who developed post-operative pocket hematoma (p 0.001). Mortality at 1 year following CIED surgery was 20% (n = 32).CIED surgery following LVAD implantation is associated with an increased risk for pocket hematoma and CIED infection. Further studies are needed to determine the risk-benefit ratio of CIED surgery in patients with LVADs.

Objectives The goal of this study was to assess the utility of transvenous lead extraction for cardiovascular implantable electronic device (CIED) infection in patients with a left ventricular assist device (LVAD). Background The utility of transvenous lead extraction for the management CIED infection in patients with a durable LVAD has not been well described. Methods Clinical and outcomes data were collected retrospectively among patients who underwent lead extraction for CIED infection after LVAD implantation at Duke University Hospital. Results Overall, 27 patients (n = 6 HVAD; n = 15 HeartMate II; n = 6 Heartmate III) underwent lead extraction for infection. Median (interquartile range) time from LVAD implantation to infection was 6.1 (2.5, 14.9) months. Indications included endocarditis (n = 16), bacteremia (n = 9), and pocket infection (n = 2). Common pathogens were Staphylococcus aureus (n = 10), coagulase-negative staphylococci (n = 7), and Enterococcus faecalis (n = 3). Sixty-eight leads were removed, with a median lead implant time of 5.7 (3.6, 9.2) years. Laser sheaths were used in all procedures, with a median laser time of 35.0 (17.5, 85.5) s. Mechanical cutting tools were required in 11 (40.7%) and femoral snaring in 4 (14.8%). Complete procedural success was achieved in 25 (93.6%) patients and clinical success in 27 (100%). No procedural failures or major adverse events occurred. Twenty-one patients (77.8%) were alive without persistent endovascular infection 1 year after lead extraction. Most were treated with oral suppressive antibiotics after extraction (n = 23 [82.5%]). Persistent infection after extraction occurred in 4 patients and was associated with 50% 1-year mortality. Conclusions Transvenous lead extraction for LVAD-associated CIED infection can be performed safely with low rates of persistent infection and 1-year mortality.

Background Catheter ablation is an important rhythm control therapy in patients with atrial fibrillation (AF) with concomitant heart failure (HF). The objective of this study was to assess the comparative efficacy of AF ablation patients with ischemic vs nonischemic heart failure. Methods We conducted a retrospective, observational cohort study of patients with HF who underwent AF ablation. Outcomes were compared based on HF etiology and included in‐hospital events, symptoms (Mayo AF Symptom Inventory [MAFSI]), and functional status (New York Heart Association class) and freedom from atrial arrhythmias at 12 months. Results Among 242 patients (n = 70 [29%] ischemic, n = 172 [71%] nonischemic), patients with nonischemic cardiomyopathy were younger (mean age 64 ± 11.5 vs 69 ± 9.1, P = .002), more often female (36% vs 17%, P = .004), and had higher mean left‐ventricular ejection fraction (47% vs 42%, P = .0007). There were no significant differences in periprocedural characteristics, including mean procedure time (243 ± 74.2 vs 259 ± 81.8 minutes, P = .1) and nonleft atrial ablation (17% vs 20%, P = .6). All‐cause adverse events were similar in each group (15% vs 17%, P = .7). NYHA and MAFSI scores improved significantly at follow‐up and did not differ according to HF etiology (P = .5; P = .10‐1.00 after Bonferroni correction). There were no significant differences in freedom from recurrent atrial arrhythmia at 12‐months between ischemic (74%) and nonischemic patients (78%): adjusted RR 0.63, 95% confidence interval 0.33‐1.19. Conclusions Catheter ablation in patients with AF and concomitant heart failure leads to significant improvements in functional and symptom status without significant differences between patients with ischemic vs nonischemic HF etiology., Catheter ablation is an important rhythm control therapy in patients with atrial fibrillation (AF) with concomitant heart failure (HF). The objective of this study was to assess the comparative efficacy of AF ablation patients with ischemic versus nonischemic heart failure. We found that catheter ablation in patients with AF and concomitant heart failure leads to significant improvements in functional and symptom status without significant differences between patients with ischemic versus nonischemic HF etiology.

Procedural and clinical outcomes of patients undergoing extraction or removal of azygous coils are not well characterized.Evaluate outcomes in patients who undergo device extraction with an azygous coil in situ.Patients undergoing extraction with an azygous coil in situ between May 2015 and January 2021 were included in this retrospective single-center analysis. Outcomes included procedural success, use of laser and mechanical cutting tools during the procedure, procedural complications, and mortality.We identified 2 patients undergoing device extraction with an azygous coil in situ with a dwell time greater than 12 months. The patients were male, aged 73 and 83 years. Both had a history of hypertension, atrial fibrillation, heart failure (ejection fractions15% and 20%), and cardiomyopathy (nonischemic and ischemic), and presented with an infection (case 1 with a single-chamber ICD and Staphylococcus aureus bacteremia, case 2 with a cardiac resynchronization therapy defibrillator pocket infection). The mean dwell time of all 6 leads extracted was 6.43 years (range 1.33-12.63 years), and the 2 azygous coils had dwell times of 1.33 and 6.04 years. In case 1, the azygous coil was inferior to the cardiac silhouette, while in case 2 it was superior. A 14F laser sheath was employed to remove both azygous coils. Both extractions were a complete procedural success in which all leads were removed completely without intraoperative complications.These cases demonstrate the variable courses of azygous coils, provide proof of concept that they can be removed safely, and illustrate that azygous coils can be removed with the same techniques that are commonly used to remove other types of leads.

Cardiac implanted electronic device (CIED) pocket and systemic infection remain common complications with traditional CIEDs and are associated with high morbidity and mortality. Leadless pacemakers may be an attractive pacing alternative for many patients following complete hardware removal for a CIED infection by eliminating surgical pocket-related complications as well as lower risk of recurrent complications.To describe use and outcomes associated with leadless pacemaker implantation following extraction of a CIED system due to infection.Patient characteristics and postprocedural outcomes were described in patients who underwent leadless pacemaker implantation at Duke University Hospital between November 11, 2014 and November 18, 2019, following CIED infection and device extraction. Outcomes of interest included procedural complications, pacemaker syndrome, need for system revision, and recurrent infection.Among 39 patients, the mean age was 71 ± 17 years, 31% were women, and the most frequent primary pacing indication was complete heart block (64.1%) with 9 (23.1%) patients being pacemaker dependent at the time of Micra implantation. The primary organism implicated in the CIED infection was Staphylococcus aureus (43.6%). Nine of the 39 patients had a leadless pacemaker implanted before or on the same day as their extraction procedure, and the remaining 30 patients had a leadless pacemaker implanted after their extraction procedure. During follow-up (mean 24.8 ± 14.7 months) after leadless pacemaker implantation, there were a total of 3 major complications: 1 groin hematoma, 1 femoral arteriovenous fistula, and 1 case of pacemaker syndrome. No patients had evidence of recurrent CIED infection after leadless pacemaker implantation.Despite a prior CIED infection and an elevated risk of recurrent infection, there was no evidence of CIED infection with a mean follow up of over 2 years following leadless pacemaker implantation at or after CIED system removal. Larger studies with longer follow-up are required to determine if there is a long-term advantage to implanting a leadless pacemaker versus a traditional pacemaker following temporary pacing when needed during the periextraction period in patients with a prior CIED infection.

BACKGROUND: Compared with medical therapy, catheter ablation of atrial fibrillation (AF) in patients with heart failure (HF) improves cardiovascular outcomes. Risk scores (CAAP-AF and APPLE) have been developed to predict the likelihood of AF recurrence after ablation, have not been validated specifically in patients with AF and HF. METHODS: We analyzed baseline characteristics, risk scores, and rates of AF recurrence 12 months post-ablation in a cohort of 230 consecutive patients with AF and HF undergoing PVI in the Duke Center for Atrial Fibrillation registry from 2009–2013. RESULTS: During a follow-up period of 12 months, 76 of 230 (33%) patients with HF experienced recurrent AF after ablation. The median APPLE and CAAP-AF scores were 1.5 [(Q1, Q3): (1.0, 2.0)] and 4.0 [(Q1, Q3): (3.0, 5.0)], respectively and were not different from those patients with and without recurrent AF. Freedom from AF was not different according to APPLE and CAAP-AF scores. Discrimination for recurrent AF with the CAAP-AF score was modest with a C-statistic of 0.60 (95% CI 0.52 – 0.67). Discrimination with the APPLE score was similarly modest, with a c-statistic of 0.54 (95% CI: 0.47 – 0.62). CONCLUSIONS: Validated predictive risk scores for recurrent AF after catheter ablation exhibit limited predictive ability in cohorts of AF and HF. Additional tools are needed to facilitate risk stratification and patient selection for AF ablation in patients with concomitant HF.

Background: Diabetes mellitus (DM) is an independent risk factor for atrial fibrillation (AF). Few studies have compared clinical outcomes after catheter ablation between patients with and those without DM. Objective: The purpose of this study was to compare AF ablation outcomes in patients with and those without DM. Methods: We performed a retrospective analysis of 351 consecutive patients who underwent first-time AF ablation. Clinical outcomes included freedom from recurrent atrial arrhythmia, symptom burden (Mayo AF Symptom Inventory score), cardiovascular and all-cause hospitalizations, and periprocedural complications. Results: Patients with DM (n = 65) were older, had a higher body mass index, more persistent AF, more hypertension, and larger left atrial diameter (P

Background: Cardiac amyloidosis is a progressive infiltrative disease involving deposition of amyloid fibrils in the myocardium and cardiac conduction system that frequently manifests with heart failure (HF) and arrhythmias, most frequently atrial fibrillation (AF), atrial flutter (AFL), and atrial tachycardia (AT). Methods: We performed an observational retrospective study of patients with a diagnosis of cardiac amyloid who underwent catheter ablation at our institution between January 1, 2011 and December 1, 2018. Patient demographics, procedural characteristics and outcomes were determined by manual chart review. Results: A total of 13 catheter ablations were performed over the study period in patients with cardiac amyloidosis, including 10 AT/AF/AFL ablations and 3 atrioventricular nodal ablations. Left ventricular ejection fraction was lower at the time of AV node ablation than catheter ablation of AT/AF/AFL (23% vs. 40%, p = 0.003). Cardiac amyloid was diagnosed based on the results of pre-ablation cardiac MRI results in the majority of patients (n = 7, 70%). The HV interval was prolonged at 60±15 ms and did not differ significantly between AV nodal ablation patients and AT/AF/AFL ablation patients (69±18 ms vs. 57±14 ms, p = 0.36). The majority of patients undergoing AT/AF/AFL ablation had persistent AF (n = 7, 70%) and NYHA class II (n = 5, 50%) or III (n = 5, 50%) HF symptoms, while patients undergoing AV node ablation were more likely to have class IV HF (n = 2, 66%, p = 0.014). Arrhythmia-free survival in CA patients after catheter ablation of AT/AF/AFL was 40% at one year and 20% at two years. Conclusions: Catheter ablation of AT/AF/AFL may be a feasible strategy for appropriately selected patients with early to mid-stage CA, whereas AV node ablation may be more appropriate in patients with advanced stage CA. This article is protected by copyright. All rights reserved.

Background Few studies have examined outcomes of catheter ablation for atrial fibrillation (AF) in patients with heart failure (HF) with preserved ejection fraction (HFpEF). Objective The purpose of this study was to compare outcomes of AF ablation in patients with HFpEF vs HF with reduced ejection fraction (HFrEF). Methods We performed a retrospective study of 230 patients with HF who underwent AF ablation, including 97 (42.2%) with HFrEF and 133 (57.8%) with HFpEF. Outcomes included adverse events, symptoms (Mayo AF Symptom Inventory [MAFSI]), New York Heart Association (NYHA) functional class, and freedom from recurrent atrial arrhythmia at 12 months. Results Overall, 150 of 230 patients had nonparoxysmal AF (62.8% HFpEF vs 63.0% HFrEF). Patients with HFpEF had a smaller mean left atrial diameter (4.4 ± 0.8 cm vs 4.7 ± 0.7 cm; P = .013) and were less likely to be taking a beta-blocker at baseline (72.9% vs 85.6%; P = .022). Median (Q1, Q3) procedure times (233 minutes [192, 290] vs 233.5 minutes [193.0, 297.5]; P = .780) and adverse events such as acute HF (3.8% vs 6.2%; P = .395) were similar between HFpEF and HFrEF patients. Freedom from recurrent atrial arrhythmia was not significantly different in HFpEF vs HFrEF patients (33.9% vs 32.6%; adjusted hazard ratio 1.47; 95% confidence interval 0.72–3.01), with similar improvements in NYHA functional class (−0.32 vs −0.19; P = .135) and MAFSI symptom severity (−0.23 vs −0.09; P = .116) after ablation. Conclusion Catheter ablation of AF seems to have similar effectiveness in patients with HF, regardless of presence of systolic dysfunction. There were no significant differences in procedural characteristics, arrhythmia-free recurrence, or functional improvements between patients with HFpEF and those with HFrEF.

Background: Lead management is an increasingly important aspect of care in patients with cardiac implantable electronic devices; however, relatively little is known about long-term outcomes after capping and abandoning leads. Methods: Using the 5% Medicare sample, we identified patients with de novo cardiac implantable electronic device implantations between January 1, 2000, and December 31, 2013, and with a subsequent lead addition or extraction ≥12 months after the de novo implantation. Patients who underwent extraction for infection were excluded. Using multivariable Cox proportional hazards models, we compared cumulative incidence of all-cause mortality, device-related infection, device revision, and lead extraction at 1 and 5 years for the extraction versus the cap and abandon group. Results: Among 6859 patients, 1113 (16.2%) underwent extraction, whereas 5746 (83.8%) underwent capping and abandonment. Extraction patients tended to be younger (median, 78 versus 79 years; P P =0.05), and had shorter lead dwell time (median, 3.0 versus 4.0 years; P P =0.027). There was no association between extraction and mortality, lead revision, or lead extraction at 5 years. Conclusions: Elective lead extraction for noninfectious indications had similar long-term survival to that for capping and abandoning leads in a Medicare population. However, extraction was associated with lower risk of device infections at 5 years.

Objectives This analysis evaluated temporal trends and factors associated with the use of dual-coil implantable cardioverter-defibrillator (ICD) leads. Background Data suggest that dual-coil ICD leads are not associated with lower mortality and can be more difficult to extract than single-coil leads. Methods A total of 435,772 patients at 1,690 hospitals underwent ICD lead insertion in the National Cardiovascular Data Registry’s ICD Registry between April 2010 and December 2015. Hospitals were classified into 3 pre-specified groups (low, decreasing, or high use) based on the frequency of dual-coil lead use. Results Nationally, the use of dual-coil leads has decreased over time, from 87% of ICD leads in early 2010 to 55% at the end of 2015. Hospitals in the low-use (n = 292) or decreasing-use (n = 561) group had more ICDs inserted by electrophysiologists compared to the high-use (n = 837) group (90% or 80% vs 46%; p Conclusions Although the use of dual-coil ICD leads has decreased over time, it continues to represent the majority of insertions in the United States. Hospital-level factors, but not patient factors, were associated with use of dual-coil ICD leads. Whether decreasing dual-coil ICD lead use has improved patient outcomes remains unknown and should be examined in large, multicenter, contemporaneous patient groups.

Cardiac implantable electronic devices (CIEDs) frequently need to be extracted due to infection, hardware failure, and other causes. The extraction of the CIED is typically performed using percutaneous methods. While these procedures are mostly performed without incident there is a small risk of significant complications. Dedicated imaging pre-CEID removal to include the central veins and heart with multidetector computed tomography (MDCT) can be utilized to evaluate the lead course and termination, the integrity of the central veins and cardiac chambers, and identify potential complications that may alter the lead extraction procedure as well as reimplantation of subsequent leads. Indications for preprocedural imaging, the technique of dedicated preprocedural lead extraction MDCT, and the approach to the interpretation of the images is discussed in this review.

Background Pulmonary wall isolation (PWI) is increasingly used as an adjunctive lesion set to compliment pulmonary vein isolation (PVI), especially in patients with persistent atrial fibrillation (AF). The objective was to compare outcomes of catheter ablation in patients with persistent AF undergoing PVI with and without adjunctive PWI. Methods We performed a retrospective study of 558 patients who underwent de novo and repeat ablation for persistent AF. Subjects were matched using propensity score adjustments. Outcomes were freedom from recurrent atrial arrhythmia and adverse events. Results Among 558 patients who underwent ablation for persistent AF, 78 (14%) underwent PVI + PWI, 255 (46%) underwent PVI, and 225 (40%) underwent PVI + linear ablation. Stratified logistic regression analysis with propensity matching revealed higher odds of recurrent arrhythmia with PVI + PWI when compared to PVI (odds ratio [OR] 2.25, 95% CI 1.08-4.69, P = .030) and when compared to PVI + linear (OR 2.31, 95% CI 1.01-5.28, P = .048). Within the PVI + PWI group, 57.7% of subjects were in normal sinus rhythm at 6 months compared to 73.9% and 72.2% in PVI and PVI + linear groups, respectively. Adverse events were rare, with 19 events total identified across all groups. Conclusions PVI + PWI does not appear to be as effective as PVI or PVI + linear ablation in reducing the recurrence of arrhythmia within 6 months of the index procedure in patients with persistent AF. A prospective, randomized controlled trial comparing these ablation techniques is needed to clarify the role of extensive substrate modification for treatment of persistent AF. Condensed Abstract PWI is increasingly used as an adjunctive lesion set to compliment PVI in patients with persistent AF. We performed a retrospective study of 558 patients who underwent de novo and repeat ablation for persistent AF to compare the outcomes between PVI with and without adjunctive PWI. We found an increased incidence in recurrence of AF and other atrial arrhythmias at 6 months in the PVI + PWI cohort compared to PVI with or without additional linear ablation. A prospective, randomized controlled trial comparing these ablation techniques is needed to clarify the role of extensive substrate modification for treatment of persistent AF.

Due to the growing number of patients treated with cardiac implantable electronic devices (CIEDs) there is an increased need for lead management, evaluation, and extraction. While CIED lead extraction has many indications, a consistent approach to preprocedural planning should be applied in all cases, including a thorough consultation with careful review of the patient's medical and device history, as well as a discussion of informed consent and shared decision-making with the patient and their loved ones. The use of chest X-ray, echocardiography, and computed tomography (CT) scan can further help with risk stratification and procedural planning. Intraprocedural echocardiography (transesophageal or intracardiac) is recommended and allows early recognition of cardiothoracic injury. Establishing an extraction team with cardiology/electrophysiology, anesthesiology, and CT surgery is is crucial to a successful and safe CIED extraction practice, including immediately available surgical backup. This hands-on review will address how to approach patients who are undergoing lead extraction, as well as several innovations in preprocedure and intraprocedural risk assessment.

Background Preprocedural multidetector computed tomography (MDCT) may identify patients at risk for mechanical complications during lead extraction. Methods To describe the use and feasibility of computed tomography scanning for preprocedural planning of lead extraction, we conducted a retrospective study of high-risk patients, who underwent electrocardiogram (ECG)-gated MDCT before planned lead extraction between January 1, 2012, and March 30, 2013. Results Among 30 patients the mean age was 63 ± 15 years, 60% were male, and 20% had prior sternotomy. Most devices were left sided (93%) and 24 had implantable defibrillators (80%). Indications for extraction included lead malfunction (n = 15; 50%), class I lead advisories (n = 11; 37%), and infection (n = 10; 33%). Overall, there were 65 leads extracted (mean 2.1 leads per patient). One extraction procedure was deferred due to MDCT evidence of significant myocardial perforation with the lead tip > 1 cm beyond the epicardium (n = 1, 3%). MDCT suggestion of lead adherence to central venous structures (n = 13, 43%) was associated with significantly longer laser times (88 ± 71 seconds vs 30 ± 37 seconds, P = 0.02) and larger sheath size (14.9 ± 1.3 vs 13.5 ± 1.2 French, P = 0.02). MDCT evidence of central venous occlusion or stenosis was not associated with increased laser times. Excluding the patient with MDCT evidence of significant perforation, clinical success was achieved in all patients (n = 29/29). Conclusions ECG-gated MDCT scanning before lead extraction may facilitate the identification of significant perforation and patients at high risk for mechanical complication.

Recently, a U-shaped association between PR-interval and the risk of developing atrial fibrillation was described, with higher risk in patients with long and short PR-intervals. Little is known regarding the association of PR-interval duration and mortality. The objective of the current study was to explore the relationship between PR-interval and major cardiovascular outcomes in patients with known coronary heart disease.Patients in sinus rhythm, undergoing coronary angiography at Duke University Medical Center between 1989 and 2010, who had significant stenosis in at least one native coronary artery, were included. Patients with arrhythmia, second- or third-degree AV-block, QRS120 ms were excluded. A total of 9,637 patients were included (median age 63, IQR 55-71 years, 67% men). After adjustment for relevant covariates, the risk of a CV event increased with a decreasing PR-interval (10 ms decrements) for PR-interval values162 ms (all-cause mortality; HR 1.057, 95% CI 1.019-1.096, P = 0.0030, composite of death or stroke; HR 1.047, 95% CI 1.011-1.085, P = 0.0095 and composite of cardiovascular death or cardiovascular rehospitalization; HR 1.032, 95% CI 1.002-1.063, P = 0.0387). No statistically significant changes in the risk associated with PR-interval for values162 ms were seen for any of the studied endpoints.In patients with coronary heart disease, a prolongation of the PR-interval was not independently associated with poor outcomes, but a PR-interval shorter than normal was associated with increased all-cause mortality and other major cardiovascular events.

CIED Removal in LVAD Infections Introduction Heart failure patients with left ventricular assist devices (LVADs) are at risk for infection. Cardiac implantable electronic devices (CIEDs) are commonly present in these patients. The course of infections in patients with an LVAD and a CIED is not well described. Methods and Results We identified 6 patients with a durable LVAD that underwent CIED removal because of an LVAD associated infection (LVADI). Patient and infection characteristics, management strategy, and clinical outcomes are described. All 6 patients were male, and the mean age was 59.6 years (range 43–72). Four of 6 patients had an ischemic cardiomyopathy, and 3 patients were diabetic. The median creatinine clearance for patients was 40.5 mg/dL (range 19–65). Five of 6 patients had a continuous flow LVAD placed as destination therapy. Four of 6 patients had a previous LVADI managed medically before the current infection leading to CIED removal. The indication for CIED removal was a bloodstream infection in 5 of 6 patients. Three of these patients had potential vegetations identified by echocardiography on device leads. The mean implanted age of the removed leads was 62 months (range 1–179), and 1 of the 6 patients experienced a procedural complication (hematoma) from CIED removal. Four of 6 patients that underwent CIED removal for an LVADI had recurrence of infection. Five of 6 patients died during the initial presentation or from repeat presentation for infection. Conclusion Despite CIED removal for an LVADI, recurrent infections are common and mortality remains high.

A 54-year-old man with nonischemic cardiomyopathy and recurrent ventricular tachycardia (VT) refractory to quinidine, sotalol, mexiletine, and amiodarone; 4 prior ablation procedures; and bilateral sympathectomy was admitted in VT storm. Cardiac magnetic resonance imaging revealed asymmetric

Background A 2008 expert consensus statement recommended an in-person follow-up visit between 2 and 12 weeks after the placement of a new cardiovascular implantable electronic device (CIED). Objective To assess outcomes associated with adherence to the experts' recommendations. Methods By using data from the National Cardiovascular Data Registry's (NCDR®) ICD Registry™ linked to Medicare claims, we studied the association between follow-up within 2–12 weeks after CIED placement between January 1, 2005, and September 30, 2008, and all-cause mortality and risk of readmission within 1 year. Results Compared with patients who did not receive the recommended follow-up (n = 43,060), those who did (n = 30,256) were more likely to be older, white, to have received a cardiac resynchronization therapy-defibrillator device, to have more advanced heart failure symptoms, and to have nonischemic dilated cardiomyopathy. In Cox proportional hazards models adjusted for patient demographic and clinical factors, mortality was lower (hazard ratio [HR] 0.93; 95% confidence interval [CI] 0.88–0.98; P = .005) but cardiovascular readmission was higher (HR 1.04; 95% CI 1.01–1.08; P = .012) among patients who received initial follow-up within 2–12 weeks after CIED placement compared with those who did not. There was no association between CIED follow-up and readmission for heart failure (HR 1.00; 95% CI 0.96–1.05; P = .878) or device-related infection (HR 1.22; 95% CI 0.98–1.51; P = .075). Conclusions Follow-up within 2–12 weeks after CIED placement was independently associated with improved survival but increased cardiovascular readmission. Quality improvement initiatives designed to increase adherence to experts' recommendations may be warranted.

Background Proper positioning of the left ventricular (LV) lead improves clinical outcomes and survival in patients receiving cardiac resynchronization therapy (CRT). Techniques of LV lead insertion using contrast injection and a telescoping system of delivery catheters to support advancement of the lead into the target branch may allow more efficient, targeted lead placement. We sought to evaluate the impact of an LV lead implant approach using telescoping-support catheters (group TS) on success rate, lead location, and procedural time compared to standard over-the-wire implant techniques (group OTW). Methods Four hundred thirty-seven consecutive patients undergoing CRT implantation were divided into group TS (n = 105) or group OTW (n = 332) based upon a review of the operative technique used for LV lead implantation. The primary outcome was success of LV lead implantation at the index procedure. Secondary endpoints included optimal positioning of the LV lead and reduction in procedural fluoroscopy time. Results Failed LV lead placement was lower (1.9% vs 8.1%, P = 0.02) and optimal lead positioning was achieved more often for group TS than group OTW (87% vs 75%, P = 0.01). In addition, there were significantly shorter fluoroscopy times for group TS versus group OTW (29.6 minutes vs 41.9 minutes, P < 0.01). Conclusion A CRT-implant approach using contrast injection and a telescoping-support catheter system results in fewer failed LV lead implants, improved LV lead location, and shorter procedure times.

This analysis evaluated temporal trends and factors associated with the use of dual-coil implantable cardioverter-defibrillator (ICD) leads.Data suggest that dual-coil ICD leads are not associated with lower mortality and can be more difficult to extract than single-coil leads.A total of 435,772 patients at 1,690 hospitals underwent ICD lead insertion in the National Cardiovascular Data Registry's ICD Registry between April 2010 and December 2015. Hospitals were classified into 3 pre-specified groups (low, decreasing, or high use) based on the frequency of dual-coil lead use.Nationally, the use of dual-coil leads has decreased over time, from 87% of ICD leads in early 2010 to 55% at the end of 2015. Hospitals in the low-use (n = 292) or decreasing-use (n = 561) group had more ICDs inserted by electrophysiologists compared to the high-use (n = 837) group (90% or 80% vs 46%; p 0.001 for both) and more extractions performed (median 7 or 11 vs 2; p 0.001 for both). Despite statistical differences, there were no clinically significant differences in patient characteristics across all 3 groups.Although the use of dual-coil ICD leads has decreased over time, it continues to represent the majority of insertions in the United States. Hospital-level factors, but not patient factors, were associated with use of dual-coil ICD leads. Whether decreasing dual-coil ICD lead use has improved patient outcomes remains unknown and should be examined in large, multicenter, contemporaneous patient groups.

Introduction: Percutaneous transvenous lead extraction of cardiovascular implantable electronic devices (CIEDs) is increasingly common. Although ICD leads are widely considered to be more difficult to extract than pacemaker leads, there are few direct comparisons. Methods/Results: Using a cohort of 368 consecutive patients undergoing lead extraction (dwell time >1 year) between 2005-2012, we compared baseline characteristics/outcomes in extractions involving pacing versus ICD leads. We defined major adverse events (MAE) as any events/complications that required procedural intervention, transfusion, or that resulted in death or serious harm during index hospitalization. Median age was 60.6 yrs and 29.6% were women. There were 136 (37%) pacing lead extractions and 232 (63%) ICD lead extractions. Pacing leads had a longer dwell time (6.14 yrs [IQR 1.2-10.9 ] versus 4.4 yrs [IQR 1.1-6.4], p Conclusions: ICD leads are more commonly extracted relative to pacemaker leads, and this difference is driven by larger numbers of lead failure within ICD leads. Despite much longer dwell times, major adverse events were similar in pacing lead cases compared with ICD extractions.

As with surgical procedures, regular surveillance of infectious complications following cardiac implantable electronic device procedures is possible with electronic means combining queries of ICD-9 codes and microbiologic data. Feedback of complication rates may lead to improved patient outcomes., Background. The optimum approach for infectious complication surveillance for cardiac implantable electronic device (CIED) procedures is unclear. We created an automated surveillance tool for infectious complications after CIED procedures. Methods. Adults having CIED procedures between January 1, 2005 and December 31, 2011 at Duke University Hospital were identified retrospectively using International Classification of Diseases, 9th revision (ICD-9) procedure codes. Potential infections were identified with combinations of ICD-9 diagnosis codes and microbiology data for 365 days postprocedure. All microbiology-identified and a subset of ICD-9 code-identified possible cases, as well as a subset of procedures without microbiology or ICD-9 codes, were reviewed. Test performance characteristics for specific queries were calculated. Results. Overall, 6097 patients had 7137 procedures. Of these, 1686 procedures with potential infectious complications were identified: 174 by both ICD-9 code and microbiology, 14 only by microbiology, and 1498 only by ICD-9 criteria. We reviewed 558 potential cases, including all 188 microbiology-identified cases, 250 randomly selected ICD-9 cases, and 120 with neither. Overall, 65 unique infections were identified, including 5 of 250 reviewed cases identified only by ICD-9 codes. Queries that included microbiology data and ICD-9 code 996.61 had good overall test performance, with sensitivities of approximately 90% and specificities of approximately 80%. Queries with ICD-9 codes alone had poor specificity. Extrapolation of reviewed infectious rates to nonreviewed cases yields an estimated rate of infection of 1.3%. Conclusions. Electronic queries with combinations of ICD-9 codes and microbiologic data can be created and have good test performance characteristics for identifying likely infectious complications of CIED procedures.

An 80-year-old man presented for evaluation of shortness of breath and fatigue four weeks after repair of a hiatal hernia. He reported a mild, nonproductive cough and abdominal bloating. Before the surgery, he had been very active and had had no dyspnea.

Heart failure patients with left ventricular assist devices (LVADs) are at risk for infection. Cardiac implantable electronic devices (CIEDs) are commonly present in these patients. The course of infections in patients with an LVAD and a CIED is not well described.We identified 6 patients with a durable LVAD that underwent CIED removal because of an LVAD associated infection (LVADI). Patient and infection characteristics, management strategy, and clinical outcomes are described. All 6 patients were male, and the mean age was 59.6 years (range 43-72). Four of 6 patients had an ischemic cardiomyopathy, and 3 patients were diabetic. The median creatinine clearance for patients was 40.5 mg/dL (range 19-65). Five of 6 patients had a continuous flow LVAD placed as destination therapy. Four of 6 patients had a previous LVADI managed medically before the current infection leading to CIED removal. The indication for CIED removal was a bloodstream infection in 5 of 6 patients. Three of these patients had potential vegetations identified by echocardiography on device leads. The mean implanted age of the removed leads was 62 months (range 1-179), and 1 of the 6 patients experienced a procedural complication (hematoma) from CIED removal. Four of 6 patients that underwent CIED removal for an LVADI had recurrence of infection. Five of 6 patients died during the initial presentation or from repeat presentation for infection.Despite CIED removal for an LVADI, recurrent infections are common and mortality remains high.

Adherens junctions, consisting of transmembrane cadherin molecules and their associated cytoplasmic alpha-, beta-, and gamma-catenin proteins, are thought to be critical for the development of stable cell adhesion and subsequent 3-dimensional tissue organization. In human endothelial cells there is a marked induction of gamma-catenin levels when cells reach confluence. We demonstrate that expression of a dominant negative ras gene product (N17ras) via adenoviral mediated gene transfer inhibits the confluent-dependent rise in gamma-catenin mRNA and protein levels. Consistent with its effects on overall gamma-catenin levels, expression of N17ras also reduces the amount of gamma-catenin associated with the adherens junction. Finally, although expression of N17ras under normal culture conditions produces no clear morphological phenotype, endothelial cells expressing a dominant negative ras gene product fail to form 3-dimensional, vascular-like structures when plated on reconstituted extracellular matrix.

We demonstrate that stimulation of primary cultures of endothelial cells with vascular endothelial cell growth factor (VEGF) results in a rapid increase in labeled guanine nucleotide bound to p21ras. Surprisingly, although VEGF stimulates ras activity, adenoviral-mediated gene transfer of a dominant negative form of ras (N17ras) had no effect on VEGF-stimulated mitogen-activated protein kinase (MAPK) activity. In contrast, treatment of endothelial cells with two structurally unrelated inhibitors of protein kinase C (PKC) abrogated VEGF-stimulated MAPK activity. In addition, inhibition of ras-Raf interactions by expression of a truncated form of Raf containing only the ras binding domain blocked VEGF-stimulated MAPK activation. These results suggest that VEGF stimulation of MAPK in endothelial cells differs from the pathway used by other members of the receptor tyrosine kinase family. In contrast, analogous to certain G-coupled receptors, VEGF appears to activate MAPK through a PKC-dependent pathway that requires a stable ras-Raf interaction but is not inhibited by N17ras expression.

Advanced heart failure patients treated with left ventricular assist devices (LVADs) frequently have ventricular arrhythmias. Given the hemodynamic support provided by LVADs, arrhythmias may be better tolerated, but the risk of sudden death in this population has not been determined. Also, the

Risk of atrial fibrillation (AF) after coronary artery bypass grafting (CABG) is high, yet the effectiveness of guideline-recommended preoperative prophylaxis in clinical practice remains uncertain. We determined the utilization and variation of preoperative AF prevention and assessed the comparative effectiveness of alternative drugs using the Society of Thoracic Surgeons multicenter Contemporary Analysis of Perioperative Cardiovascular Surgical Care (CAPS-Care) registry. Among 2,177 patients who underwent high-risk CABG and/or valve surgery, the mean age was 71 ± 9, 66% were men, 26% had chronic lung disease, and 21% had cerebrovascular disease. Overall use of AF prophylaxis was 84% and varied across sites (range 52% to 100%). The most common preventive agents were beta blockers (72%), followed by calcium antagonists (17%). Postoperatively, 30% (n = 646) developed AF at a median of 2 (25th to 75th percentiles: 1 to 3) days after surgery. Increasing age, height, white race, body mass index35, New York Heart Association class IV heart failure, preoperative dialysis, and concomitant aortic valve replacement were associated with greater odds of postoperative AF (p0.05 for all). Preoperative amiodarone use was associated with a trend to reduction of postoperative AF (26%, adjusted odds ratio 0.72 [95% confidence interval 0.51 to 1.00], p = 0.052). After adjustment, the odds of postoperative AF were not statistically different across agents. In conclusion, use of AF prophylaxis before surgery varied significantly. In this high-risk population, we were unable to demonstrate that any of the commonly used preventive agents were associated with lower rates of AF compared with alternatives or no treatment.

Proper positioning of the left ventricular (LV) lead improves clinical outcomes and survival in patients receiving cardiac resynchronization therapy (CRT). Techniques of LV lead insertion using contrast injection and a telescoping system of delivery catheters to support advancement of the lead into the target branch may allow more efficient, targeted lead placement. We sought to evaluate the impact of an LV lead implant approach using telescoping-support catheters (group TS) on success rate, lead location, and procedural time compared to standard over-the-wire implant techniques (group OTW).Four hundred thirty-seven consecutive patients undergoing CRT implantation were divided into group TS (n = 105) or group OTW (n = 332) based upon a review of the operative technique used for LV lead implantation. The primary outcome was success of LV lead implantation at the index procedure. Secondary endpoints included optimal positioning of the LV lead and reduction in procedural fluoroscopy time.Failed LV lead placement was lower (1.9% vs 8.1%, P = 0.02) and optimal lead positioning was achieved more often for group TS than group OTW (87% vs 75%, P = 0.01). In addition, there were significantly shorter fluoroscopy times for group TS versus group OTW (29.6 minutes vs 41.9 minutes, P0.01).A CRT-implant approach using contrast injection and a telescoping-support catheter system results in fewer failed LV lead implants, improved LV lead location, and shorter procedure times.

Cardiovascular magnetic resonance imaging (cMRI) may provide a noninvasive method to test for pulmonary vein (PV) isolation after ablation for atrial fibrillation (AF) by detecting changes in PV contraction.PV contraction (the maximal percentage change in PV cross-sectional area [CSA] during the cardiac cycle) measured 1 month before and 2 months after PV isolation was compared in 63 PVs from 16 patients with medically refractory AF. Repeat cMRI imaging and invasive catheter mapping was performed prior to repeat PV ablation in 50 PVs from 14 additional patients with recurrent AF. Contraction in PVs with sustained isolation after the initial ablation was compared to contraction in PVs with electrical reconnection to adjacent atrium. Receiver operating characteristic (ROC) curve analysis was performed to determine the optimal cutoff PV contraction value for prediction of PV-atrial reconnection after ablation. The cutoff value was then prospectively tested in 40 PVs from 12 additional patients.PV contraction decreased after AF ablation (22.4 ± 10% variation in CSA before ablation vs 10.1 ± 8% variation in CSA after ablation, P0.00001). PVs with sustained isolation on invasive mapping contracted less than PVs with electrical reconnection to adjacent atrium (13.7 ± 10.6% vs 21.4 ± 9.3%, P = 0.021). PV contraction produced a c-index of 0.74 for prediction of PV-atrial reconnection after ablation and17% variation in PV CSA predicted reconnection with a sensitivity of 84.6% and specificity of 66.7%.PV contraction is reduced by ablation. PV contraction measurement may provide a noninvasive method to test for PV isolation after ablation procedures.

Left atrial radiofrequency catheter ablation has been recognized as an important treatment option for drug-refractory symptomatic atrial fibrillation.1 Recent consensus on technique favors catheter ablation directed to the left atrium near the pulmonary vein (PV) ostium to achieve PV isolation.2 However, ablation in the region of the ligament of Marshall (LOM) to achieve electrical isolation of the left PVs can be difficult because of variable catheter stability. The superior extent of the LOM protrudes into the body of the left atrium between the anterior region of the left PV antrum and the left atrial appendage (Figure 1A). Inadvertent misdirection of ablative lesions anterior to the LOM in the region of the left atrial appendage increases the risk of cardiac perforation and does not contribute to successful PV isolation, and misdirection of ablative lesions posteriorly into the left PV or posterior left PV antrum can result in PV stenosis or fatal esophageal injury,2 respectively. Thus, circumferential isolation of the left PVs via precise delivery of ablative lesions outside the PV ostium, including the region of the LOM ridge, would be expected to enhance procedural safety and efficacy.3 More specifically, …

We have used adenoviral-mediated gene transfer of a constitutively active (V12rac1) and dominant negative (N17rac1) isoform of rac1 to assess the role of this small GTPase in cardiac myocyte hypertrophy. Expression of V12rac1 in neonatal cardiac myocytes results in sarcomeric reorganization and an increase in cell size that is indistinguishable from ligand-stimulated hypertrophy. In addition, V12rac1 expression leads to an increase in atrial natriuretic peptide secretion. In contrast, expression of N17rac1, but not a truncated form of Raf-1, attenuated the morphological hypertrophy associated with phenylephrine stimulation. Consistent with the observed effects on morphology, expression of V12rac1 resulted in an increase in new protein synthesis, while N17rac1 expression inhibited phenylephrine-induced leucine incorporation. These results suggest rac1 is an essential element of the signaling pathway leading to cardiac myocyte hypertrophy.

Background. The small guanosine triphosphate-binding protein ras regulates a signal transduction cascade linking cell surface receptors to mitogen-activated protein kinase (MAPK). Because the molecular signaling mechanisms underlying cardiac hypertrophy remain unclear, the current study examined the regulatory role of ras in both the biochemical and morphologic aspects of hypertrophy. Methods. Adenoviral-mediated gene transfer was used to express a dominant negative mutant of ras (rasN17) at high efficiency in primary neonatal ventricular myocytes. Beta-galactosidase staining and Western blot analysis confirmed successful transfection and expression of the rasN17 gene product. MAPK activity was measured by an in vitro kinase assay resulting in radioactive phosphorus labeled product. Morphologic hypertrophy was assessed by fluorescdn-conjugated phalloidin. Results. Compared with uninfected or control adenoviral-infected cells, myocytes infected with rasN17 demonstrated attenuated basal MAPK activity. In contrast, rasN17 expression did not affect endothelin 1-induced MAPK activation. Morphologic studies showed that although rasN17 produced a phenotypic difference in the basal state, the ability of cardiac myocytes to morphologically respond to endothelin 1 stimulation, as manifested by sarcomeric reorganization, remained unaltered by the expression of the rasN17 gene product. Conclusions. Endothelin 1-stimulated MAPK activation and endothelin 1-induced morphologic hypertrophy are ras-independent processes.

Objectives We tested whether an assessment of myocardial scarring by cardiac magnetic resonance imaging (MRI) would improve risk stratification in patients evaluated for implantable cardioverter-defibrillator (ICD) implantation. Background Current sudden cardiac death risk stratification emphasizes left ventricular ejection fraction (LVEF); however, most patients suffering sudden cardiac death have a preserved LVEF, and many with poor LVEF do not benefit from ICD prophylaxis. Methods One hundred thirty-seven patients undergoing evaluation for possible ICD placement were prospectively enrolled and underwent cardiac MRI assessment of LVEF and scar. The pre-specified primary endpoint was death or appropriate ICD discharge for sustained ventricular tachyarrhythmia. Results During a median follow-up of 24 months the primary endpoint occurred in 39 patients. Whereas the rate of adverse events steadily increased with decreasing LVEF, a sharp step-up was observed for scar size >5% of left ventricular mass (hazard ratio [HR]: 5.2; 95% confidence interval [CI]: 2.0 to 13.3). On multivariable Cox proportional hazards analysis, including LVEF and electrophysiological-study results, scar size (as a continuous variable or dichotomized at 5%) was an independent predictor of adverse outcome. Among patients with LVEF >30%, those with significant scarring (>5%) had higher risk than those with minimal or no (≤5%) scarring (HR: 6.3; 95% CI: 1.4 to 28.0). Those with LVEF >30% and significant scarring had risk similar to patients with LVEF ≤30% (p = 0.56). Among patients with LVEF ≤30%, those with significant scarring again had higher risk than those with minimal or no scarring (HR: 3.9; 95% CI: 1.2 to 13.1). Those with LVEF ≤30% and minimal scarring had risk similar to patients with LVEF >30% (p = 0.71). Conclusions Myocardial scarring detected by cardiac MRI is an independent predictor of adverse outcome in patients being considered for ICD placement. In patients with LVEF >30%, significant scarring (>5% LV) identifies a high-risk cohort similar in risk to those with LVEF ≤30%. Conversely, in patients with LVEF ≤30%, minimal or no scarring identifies a low-risk cohort similar to those with LVEF >30%.