Jude Clancy

Hyperkalemia induced T wave oversensing leading to loss of biventricular pacing and inappropriate ICD shocks.

Inappropriate ICD shocks remain a common problem. Double counting of single ventricular events can occur with biventricular ICDs implanted before univentricular sensing was available. Often this is due to a tachyarrhythmia or loss of left ventricular capture. This report describes a patient who developed hyperkalemia during hemodialysis, received inappropriate ICD shocks and experienced loss of biventricular pacing due to T wave rather than QRS double counting. Oversensing was abolished by reducing the potassium content of the dialysis bath. This underscores the need for careful interpretation of saved electrograms to determine the cause for, and appropriate treatment of, device related problems. (PACE 2004; 27:681–683)

2017 HRS expert consensus statement on cardiovascular implantable electronic device lead management and extraction

Fred M. Kusumoto, MD, FHRS, FACC, Chair, Mark H. Schoenfeld, MD, FHRS, FACC, FAHA, CCDS, Vice-Chair, Bruce L. Wilkoff, MD, FHRS, CCDS, Vice-Chair, Charles I. Berul, MD, FHRS, Ulrika M. Birgersdotter-Green, MD, FHRS, Roger Carrillo, MD, MBA, FHRS, Yong-Mei Cha, MD, Jude Clancy, MD, Jean-Claude Deharo, MD, FESC, Kenneth A. Ellenbogen, MD, FHRS, Derek Exner, MD, MPH, FHRS, Ayman A. Hussein, MD, FACC, Charles Kennergren, MD, PhD, FETCS, FHRS, Andrew Krahn, MD, FRCPC, FHRS, Richard Lee, MD, MBA, Charles J. Love, MD, CCDS, FHRS, FACC, FAHA, Ruth A. Madden, MPH, RN, Hector Alfredo Mazzetti, MD, JoEllyn Carol Moore, MD, FACC, Jeffrey Parsonnet, MD, Kristen K. Patton, MD, Marc A. Rozner, PhD, MD, CCDS, Kimberly A. Selzman, MD, MPH, FHRS, FACC, Morio Shoda, MD, PhD, Komandoor Srivathsan, MD, Neil F. Strathmore, MBBS, FHRS, Charles D. Swerdlow, MD, FHRS, Christine Tompkins, MD, Oussama Wazni, MD, MBA

3D Real-Time Intracardiac Echocardiographic Visualization of Atrial Structures Relevant to Atrial Fibrillation Ablation

cardiac imaging is critical for the success of interventional electrophysiological procedures. Fluoroscopy is highly beneficial for real-time catheter visualization, but it uses ionizing radiation and fails to provide detailed cardiac anatomy. Magnetic resonance imaging and computed tomography

Percutaneous occlusion balloon as a bridge to surgery in a swine model of superior vena cava perforation.

BACKGROUND Superior vena cava (SVC) perforation is a rare but potentially fatal complication of transvenous lead removal. OBJECTIVE The aim of this study was to evaluate the feasibility of hemodynamic stabilization using an occlusion balloon during SVC tear in a porcine model. METHODS A surgically induced SVC perforation was created in Yorkshire cross swine (n = 7). Three animals were used to develop and test surgical repair methods. Four animals were used to evaluate hemodynamic, behavioral, and neurological effects up to 5 days after SVC tear and repair. An occlusion balloon (Bridge Occlusion Balloon, Spectranetics Corporation, Colorado Springs, CO) was percutaneously delivered through the femoral vein to the location of the injury and inflated. Once hemodynamic control was achieved, the perforation was surgically repaired. RESULTS After SVC perforation and clamp release, the rate of blood loss was 7.0 ± 0.8 mL/s. Mean time from SVC tear to occlusion balloon deployment was 55 ± 12 seconds, during which mean arterial pressure decreased from 56 ± 2 to 25 ± 3 mm Hg and heart rate decreased from 76 ± 7 to 62 ± 7 beats/min. After the deployment of the occlusion balloon, the rate of blood loss decreased by 90%, to 0.7 ± 0.2 mL/s. The mean time of balloon occlusion of the SVC was 16 ± 4 minutes and hemodynamic measures returned to baseline levels during this time. Study animals experienced no major complications, demonstrated stable recovery, and exhibited normal neurological function at each postoperative assessment. CONCLUSION Endovascular temporary balloon occlusion may be a feasible option to reduce blood loss, maintain hemodynamic control, and provide a bridge to surgery after SVC injury.

Incidence and Predictors of Perioperative Complications With Transvenous Lead Extractions: Real-World Experience With National Cardiovascular Data Registry

Background: Transvenous lead extraction is an integral part of management of patients with cardiovascular implantable electronic devices. Real-world incidence and predictors of perioperative complications in extractions involving implantable cardioverter-defibrillator leads have not been described in detail. Methods and Results: Data from the National Cardiovascular Data Registry Implantable Cardioverter-Defibrillator Registry were analyzed. Lead extraction was defined as removal of leads implanted for >1 year. Predictors of major perioperative complications for all extraction procedures (11 304) and for high-voltage lead (8362, 74%), across 762 centers, were analyzed using univariate and multivariate logistic regression. Major complication occurred in 258 (2.3%) extraction procedures. Of these 258 with a complication, 41 (16%) required urgent cardiac surgery. Of these 41, 14 (34%) died during surgery. Among the total 98 (0.9%) deaths reported, 18 (0.16% of total) occurred during transvenous lead extraction. In multivariable logistic regression analysis, female sex, admission other than electively for procedure, ≥3 leads extracted, longer implant duration, dislodgement of other leads, and patient’s clinical status requiring lead extraction (infection/perforation) were associated with increased risk of complications. Smaller lead diameter, flat versus round coil shape, and greater proximal surface coil area were multivariate predictors of major perioperative complications specific to high-voltage leads. Conclusions: The rate of major complications and mortality with transvenous lead extraction is similar in the real-world outcomes to that reported in recent single-center studies from high-volume centers. There is significant risk of urgent cardiac surgery, which carries a high mortality, and planning for appropriate cardiothoracic surgery backup is imperative.

Cellularity and structure of fresh human coronary thrombectomy specimens; presence of cells with markers of progenitor cells.

Acute coronary syndromes and acute myocardial infarctions are often related to plaque rupture and the formation of thrombi at the site of the rupture. We examined fresh coronary thrombectomy specimens from patients with acute coronary syndromes and assessed their structure and cellularity. The thrombectomy specimens consisted of platelets, erythrocytes and inflammatory cells. Several specimens contained multiple cholesterol crystals. Culture of thrombectomy specimens yielded cells growing in various patterns depending on the culture medium used. Culture in serum‐free stem cell enrichment medium yielded cells with features of endothelial progenitor cells which survived in culture for a year. Immunohistochemical analysis of the thrombi revealed cells positive for CD34, cells positive for CD15 and cells positive for desmin in situ, whereas cultured cell from thrombi was desmin positive but pancytokeratin negative. Cells cultured in endothelial cell medium were von Willebrand factor positive. The content of coronary thrombectomy specimens is heterogeneous and consists of blood cells but also possibly cells from the vascular wall and cholesterol crystals. The culture of cells contained in the specimens yielded multiplying cells, some of which demonstrated features of haematopoietic progenitor cells and which differentiated into various cell‐types.

Caveat Emptor: Implantable Devices in End‐Stage Renal Disease

Cardiovascular disease is the leading cause of mortality in patients, with chronic kidney disease (CKD) accounting for more than half of all deaths in this population. Even a modest decrease in renal function has been identified as a powerful, independent risk factor for cardiovascular death.1,2 In addition, more than 400,000 people in the United States have end-stage renal disease (ESRD) requiring dialysis therapy, with some estimates predicting more than 2 million people by the year 2030.3 The prognosis for these individuals is poor, with mortality rates in excess of 20% during the first year of dialysis.4 Cardiac disease remains the major cause of death in patients with ESRD, accounting for 43% of all-cause mortality. Furthermore, 61% of all cardiac deaths and 26% of all deaths in ESRD patients are presumed to be arrhythmic in etiology.5 The mortality rate for dialysis patients who survive sudden cardiac death is 85% at 1 year.6 Based on these data, one would expect a substantial benefit for defibrillator (ICD) therapy in patients with ESRD. However, any device benefit may be negated by a high-mortality rate due to noncardiac causes and a high risk of perioperative complications. The goal of the study by Tompkins et al.7 was to examine device-related complications in patients with CKD. The authors retrospectively reviewed records of 1,440 patients undergoing pacemaker or defibrillator implantation. They stratified them according to kidney function and examined a composite endpoint of bleeding complications and infection in each group. The authors found that deteriorating renal function was associated with increased risk of device-related complications. While mild renal insufficiency did not confer much risk, there was an alarming increase in complications associated with deteriorating kidney function. Compared with controls with normal renal function, the risk of bleeding increased more than twofold in patients with moderate renal dysfunction (creatinine clearance 30–59 cc/min) and approximately sevenfold in patients with ESRD (< 15 cc/min or receiving hemodialysis). More than 50% of infections occurred in patients with ESRD, giving rise to a staggering 12.5% incidence of infection. This study has several limitations. It is highly probable that due to selection bias, the CKD patients studied represent a “healthy responder” population. This is particularly true of those receiving elective prophylactic primary prevention defibrillators. Thus, the risk of device-related complications