Prevalence and predictors of Twiddler's syndrome.

BACKGROUND: Twiddler's syndrome is a poorly understood clinical phenomenon when patients either consciously or subconsciously rotate their cardiac device resulting in lead dislodgement. We aimed to determine the true prevalence and risk factors associated with Twiddler's syndrome in a real-world population. METHODS: A retrospective chart review was performed on all patients who underwent cardiac device implantation from January 1st 2017 until Jan 1st 2022. We specifically searched for the terms "Twiddler" or "Twiddler's" imbedded within the text of the medical chart. Demographic and clinical variables were collected from the electronic medical record system. We utilized multivariable logistic regression analysis as well as Kaplan-Meier prediction models to determine independent clinical predictors of Twiddler's syndrome as well as associated mortality, respectively. RESULTS: Twenty one out of 1793 patients (1.2%) were identified as having Twiddler's syndrome after chart review. Independent variables associated with Twiddler's syndrome were female sex (OR 3.76; 95% CI 1.29-10.95), antidepressant medications (OR 3.58; 95% CI 1.07-11.99), and BMI (OR 1.08; 95% CI 1.03-1.31). There was no increased six-month mortality via Kaplan-Meier analysis. CONCLUSION: Our study shows that 1.2% of patients in our real-world population had evidence of Twiddler's syndrome. Independent predictors of Twiddler's syndrome include female sex, antidepressant medications as well as BMI.

Patients' and Physicians' Perceptions Regarding the Benefits of Atrial Fibrillation Ablation.

BACKGROUND: It is unclear whether patients and physicians understand that atrial fibrillation ablation (AFA) has been shown to only improve symptomology and not reduce morbidity or mortality. METHODS: Note that 177 of 445 (40%) consecutive patients referred to an electrophysiology clinic for atrial fibrillation (AF) management responded anonymously to our survey via mail. Note that 105 of 656 (15%) physicians responded to our survey via email. Comparisons among groups were conducted using χ2 test for categorical variables. Odds ratios and 95% confidence intervals were estimated by using a multivariate logistic regression model. RESULTS: Almost half of patients and physicians believed AF ablation (AFA) would eliminate the need for anticoagulation (43% vs. 44%, P > 0.05) while the majority of both groups believed AFA would improve survival (58% vs. 67%, P = 0.308). The great majority of both groups believed AFA would decrease stroke rates (89% vs. 80%, P = 0.106). When comparing noncardiologists (n = 86) to cardiologists (n = 19), noncardiologists were more likely to believe that an AFA would eliminate the need for anticoagulation 49% vs. 21% (X = 4.9, P = 0.04), improve survival 80% vs. 11% (X = 30.2, P < 0.001), and decrease stroke 87% vs. 44% (X = 15.6, P < 0.001), respectively. CONCLUSIONS: The perceived benefit of AFA by patients and physicians is not supported by the medical literature. It is the responsibility of the electrophysiology community to educate patients and referring physicians regarding the true benefits of AFA. In addition, our study displays the great need for long-term clinical trials examining the impact AFA has on morbidity and mortality.

Accelerated Implantable Defibrillator Battery Depletion Secondary to Lithium Cluster Formation: A Case Series.

BACKGROUND: Device failure from unanticipated and precipitous battery depletion is uncommon but can be life-threatening. Multiple mechanisms of battery failure have been previously described in the medical literature. METHODS: However, in this current case series, we describe the largest cohort of patients (n = 4) with St. Jude (St. Paul, MN, USA) early implantable defibrillator battery depletion attributable to lithium cluster formation causing short circuit and high current drain. CONCLUSION: Clinicians must be aware of this occult cause of device failure and more studies are needed to determine its true prevalence.

Cardiac implantable electronic device reutilization: battery life of explanted devices at a tertiary care center.

INTRODUCTION: Prior studies have suggested that pacemaker reuse may be a reasonable alternative to provide device therapy in the low- and middle-income countries. We studied explant indications and remaining battery life of cardiac implantable electronic devices (CIEDs) at a tertiary medical center. METHODS AND RESULTS: We conducted a retrospective review of all CIEDs extracted at the University of Michigan between 2007 and 2011. Devices were considered reusable if battery longevity was ≥48 months or >75% battery life was remaining; there was no evidence of electrical malfunction, and they were not under advisory or recall. Eight hundred and one CIEDs were explanted: Medtronic (MDT [Medtronic Inc., Minneapolis, MN, USA]; 454), Boston Scientific (BS [Boston Scientific Corp., Natick, MA, USA])/Guidant (GDT; 255 [Guidant Corp., St. Paul, MN, USA]), St. Jude Medical (SJM; 73 [St. Paul, MN, USA]), and Biotronik (BTK; 15 [Biotronik GmBH, Berlin, Germany]). After eliminating devices explanted for elective replacement indicator (ERI, 541), 51.9% of pacemakers (41/79), 54.2% of implantable cardioverter-defibrillators (ICDs) (64/118), and 47.6% of cardiac resynchronization therapy and defibrillation (CRT-D) devices (30/63) had sufficient battery life and no evidence of electrical malfunction to be considered for reuse. A logistic regression analysis found that the indications for device removal independently predicted reusability: upgrade to an ICD (odds ratio [OR] 162.8, P < 0.001) or CRT-D (OR 63.8, P < 0.001), infection (OR 110.7, P < 0.001), heart transplantation or left ventricular assist device placement (OR 56.6, P < 0.001), and device removal at patient's request (OR 115.4, P < 0.001). CONCLUSION: The majority of explanted CIEDs for reasons other than ERI have an adequate battery life and, if proven safe, may conceivably be reutilized for basic pacing in underserved nations where access to this life-saving therapy is limited.

Heart Rhythm Society members' views on pacemaker and implantable cardioverter-defibrillator reuse.

BACKGROUND: Reuse of cardiac implantable electronic devices (CIEDs) may help address the unmet need among patients in low- and middle-income countries (LMICs). METHODS: To examine Heart Rhythm Society (HRS) physicians' opinions regarding CIED reuse, an online survey eliciting attitudes toward CIED reuse was sent to all 3,380 HRS physician members. RESULTS: There were 429 responses (response rate 13%). A large majority of respondents agreed or strongly agreed that resterilization of devices for reimplantation in patients who cannot afford new devices may be safe (370, 87%) and, if proven to be safe, would be ethical (375, 88%). A total of 340 (81%) respondents would be comfortable asking their patients to consider donating their device, and 353 (84%) would be willing to reimplant a resterilized device if it were legal. The most commonly cited concerns about device reuse were infection (270, 64%) and device malfunction (125, 29%). Respondents from the United States and Canada had more favorable impressions of device reuse than respondents from other high-income countries (P < 0.05 for three of five positive statements regarding reuse), and were less likely to cite ethical concerns (P < 0.001). However, when responses from all high-income countries were compared with lower- and upper-middle income countries, there were no significant differences in the rates of approval. CONCLUSIONS: HRS survey respondents support the concept of CIED reuse for patients in LMICs who cannot afford new devices. Studies are needed to demonstrate the clinical efficacy and safety of this practice and to identify potential barriers to adoption among physicians.

Prevalence and predictors of complications of radiofrequency catheter ablation for atrial fibrillation.

INTRODUCTION: Up to 6% of patients experience complications after radiofrequency catheter ablation (RFA) of atrial fibrillation (AF). The purpose of this study is to determine the prevalence and predictors of periprocedural complications after RFA for AF. METHODS AND RESULTS: The subjects were 1,295 consecutive patients (age = 60 ± 10 years) who underwent RFA (n = 1,642) for paroxysmal (53%) or persistent AF (47%) from January 2007 to January 2010. A complication occurred in 57 patients (3.5%); a vascular access complication in 31 (1.9%); pericardial tamponade in 20 (1.2%); a thromboembolic event in 4 (0.2%); deep venous thrombosis in 1 (<0.01%); and pulmonary vein stenosis in 1 patient (<0.01%). There were no procedure-related deaths. On multivariate analysis, female gender (OR = 2.27; ±95% CI: 1.31-2.57, P < 0.01) and procedures performed in July or August (OR = 2.10; ±95% CI: 1.16-3.80, P = 0.01) were independent predictors of any complication. For vascular complications, treatment with clopidogrel (OR = 4.40; ±95% CI: 1.43-13.53, P = 0.01), female gender (OR = 3.65; ±95% CI: 1.72-7.75, P < 0.01) and performing RFA in July or August (OR = 2.71; ±95% CI: 1.25-5.87, P = 0.01) were independent predictors. The only predictor of cardiac tamponade was prior RFA (OR = 3.32; ±95% CI: 0.95-11.61; P < 0.05). CONCLUSION: Prevalence of perioperative complications for RFA of AF is 3.5% and vascular access complications constitute the majority. The need for clopidogrel therapy should be carefully considered prior to RFA. At teaching institutions close supervision should be exercised during vascular access early in the year. Improvements in ablation technology and elimination of the need for repeat procedures may decrease the risk of pericardial tamponade.

Recovery of pacemakers and defibrillators for analysis and device advance directives: electrophysiologists' perspectives.

BACKGROUND: Following high-profile device failures, the Heart Rhythm Society emphasized the need for postmarketing surveillance by recommending that physicians return all explanted devices to the manufacturer for analysis. METHODS: We conducted a national survey of electrophysiologists (EPs) regarding recovery for analysis of explanted pacemakers and implantable cardioverter defibrillators (devices), and attitudes toward device-specific advance directives to facilitate return of devices. Online survey invitations were sent in four waves from December 2008 to June 2009 to 300 e-mail addresses from the Heart Rhythm Society member database. RESULTS: From 250 invitations, there were 95 responses (38%). Demographics included average age 50 years (range, 31-87); 95% male; 81% Caucasian. Only 23% reported returning all explanted devices to the manufacturers. Of all the respondents, 32% discarded >10 devices/year as medical waste, 42% stored devices in a box in the electrophysiology lab, and 10% donated at least 1 device/year to charity for reuse overseas. Sixty-seven percent felt that it would not be helpful to have an advance directive specifying what the patient would want done with their device postmortem. CONCLUSIONS: Few EPs return all explanted devices or send interrogation reports to the manufacturers, though nearly all said it was easy to do so. A majority either dispose of explanted devices as medical waste or store them in laboratories or offices, and a small percentage donate for reuse in underserved nations or to veterinary hospitals. This study suggests a need for initiatives such as educational campaigns to increase the retrieval and return of devices, either for analysis or reuse.

Pacemaker reuse in a 65-year-old woman in the Philippines with severe medical need.

As disparities in healthcare between the industrialized world and low- and middle-income countries (LMIC) continue to widen, novel methods of delivering cardiovascular therapies-specifically electrophysiological devices-must be explored. Post-mortem pacemaker donation is a safe and effective method of decreasing the morbidity associated with cardiovascular disease in LMIC.

Time to cardioversion of recurrent atrial arrhythmias after catheter ablation of atrial fibrillation and long-term clinical outcome.

INTRODUCTION: It is unclear whether early restoration of sinus rhythm in patients with persistent atrial arrhythmias after catheter ablation of atrial fibrillation (AF) facilitates reverse atrial remodeling and promotes long-term maintenance of sinus rhythm. The purpose of this study was to determine the relationship between the time to restoration of sinus rhythm after a recurrence of an atrial arrhythmia and long-term maintenance of sinus rhythm after radiofrequency catheter ablation of AF. METHODS AND RESULTS: Radiofrequency catheter ablation was performed in 384 consecutive patients (age 60 +/- 9 years) for paroxysmal (215 patients) or persistent AF (169 patients). Transthoracic cardioversion was performed in all 93 patients (24%) who presented with a persistent atrial arrhythmia: AF (n = 74) or atrial flutter (n = 19) at a mean of 51 +/- 53 days from the recurrence of atrial arrhythmia and 88 +/- 72 days from the ablation procedure. At a mean of 16 +/- 10 months after the ablation procedure, 25 of 93 patients (27%) who underwent cardioversion were in sinus rhythm without antiarrhythmic therapy. Among the 46 patients who underwent cardioversion at < or =30 days after the recurrence, 23 (50%) were in sinus rhythm without antiarrhythmic therapy. On multivariate analysis of clinical variables, time to cardioversion within 30 days after the onset of atrial arrhythmia was the only independent predictor of maintenance of sinus rhythm in the absence of antiarrhythmic drug therapy after a single ablation procedure (OR 22.5; 95% CI 4.87-103.88, P < 0.001). CONCLUSION: Freedom from AF/flutter is achieved in approximately 50% of patients who undergo cardioversion within 30 days of a persistent atrial arrhythmia after catheter ablation of AF.

Disparities Regarding Inadequate Automated External Defibrillator Training and Potential Barriers to Successful Cardiac Resuscitation in Public School Systems.

Installation of automated external defibrillators (AEDs) in public schools has been shown to improve outcomes for children with sudden cardiac arrest (SCA). However, the adequacy of faculty AED training and potential barriers to successful cardiac resuscitation remain unknown. A questionnaire was mailed to all public schools in the state of Illinois (n = 3796). The survey focused on the demographic variables of each school as well as the confidence of the responder regarding effectiveness of AED training. 2,192 surveys were included in this study (58% response rate). Independent variables for perceived inadequate AED training were schools that were predominantly black (odds ratio [OR] 3.93; 3.01 to 5.13) or Hispanic (OR 2.75; 2.11 to 3.58), elementary schools (OR 2.05; 1.69 to 2.50), schools with <250 students (OR 1.69; 1.19 to 2.40) and <25 faculty (OR 1.54; 1.10 to 2.15). Eighty-eight percent of responders cited at least one barrier to successful AED utilization. Location in a town setting (OR 9.34; 4.73 to 18.44) or rural setting (OR 3.18; 2.47 to 4.10) as well as upper socioeconomic status (OR 3.85; 2.04 to 7.29) were found to be predictors of schools with no barriers to AED utilization.

Pacemaker recycling: A notion whose time has come.

The purpose of this paper is to summarize the need, feasibility, safety, legality, and ethical perspectives of pacemaker reutilization in low- and middle-income countries (LMICs). It will also describe, in-depth, Project My Heart Your Heart (PMHYH) as a model for pacemaker reuse in LMICs. The primary source of the discussion points in this paper is a collection of 14 publications produced by the research team at the University of Michigan and its collaborative partners. The need for pacemaker reutilization in LMICs is evident. Numerous studies show that the concept of pacemaker reutilization in LMICs is feasible. Infection and device malfunction are the main concerns in regard to pacemaker reutilization, yet many studies have shown that pacemaker reuse is not associated with increased infection risk or higher mortality compared with new device implantation. Under the right circumstances, the ethical and legal bases for pacemaker reutilization are supported. PMHYH is a proof of concept pacemaker donation initiative that has allowed funeral home and crematory directors to send explanted devices to an academic center for evaluation and re-sterilization before donation to underserved patients in LMICs. The time is now to pursue large-scale studies and trials of pacemaker reuse for the betterment of society. PMHYH is leading the way in the effort and is poised to conduct a prospective randomized, non-inferiority, multicenter study to confirm the clinical efficacy and safety of pacemaker reuse, for clinical and legal support.

Prevalence and predictors of inappropriate anticoagulation in patients with a CHA2DS2-VASc score of 0 and atrial fibrillation.

BACKGROUND: Previous studies have shown underutilization of anticoagulation therapy in patients with atrial fibrillation and a CHA2DS2-VASc score ≥2; however there exists little data regarding the inappropriate use of anticoagulation in patients with a CHA2DS2-VASc score of 0. We aimed to determine the true prevalence and predictors of inappropriate anticoagulation therapy in patients with atrial fibrillation and a CHA2DS2-VASc score of 0. METHODS: A retrospective chart review was performed on all patients with atrial fibrillation and a CHA2DS2-VASc score of 0 in our institution from January 2009 to January 2016. Demographic and clinical data were collected from the electronic medical record. We utilized multivariable logistic regression analysis to determine independent clinical predictors of inappropriate anticoagulation administration. RESULTS: 512 patients were identified with a CHA2DS2-VASc score of 0 and a diagnosis of atrial fibrillation. Of the 137 patients prescribed anticoagulation, 64 patients were identified as inappropriately treated with anticoagulation therapy after assessing for other indications of warfarin or novel anticoagulant therapy. Independent variables associated with inappropriate anticoagulation administration were age (OR 1.07; 95% CI 1.03-1.10), body mass index (OR 1.06; 95% CI 1.01-1.10), absence of current aspirin use (OR 13.50; 95% CI 6.00-30.54) and persistent atrial fibrillation (OR 2.34; 95% CI 1.11-4.94). CONCLUSIONS: Our study shows that 12% of patients with a CHA2DS2-VASc score of 0 were inappropriately prescribed anticoagulant therapy. Independent predictors of unnecessary anticoagulation were age, body mass index, absence of current aspirin use and persistent atrial fibrillation.

Cleaning and Sterilization of Used Cardiac Implantable Electronic Devices With Process Validation: The Next Hurdle in Device Recycling.

OBJECTIVES: This study sought to develop a validated, reproducible sterilization protocol, which could be used in the reprocessing of cardiac implantable electronic devices (CIEDs). BACKGROUND: Access to cardiac CIED therapy in high-income and in low- and middle-income countries varies greatly. CIED reuse may reduce this disparity. METHODS: A cleaning and sterilization protocol was developed that includes washing CIEDs in an enzymatic detergent, screw cap and set screw replacement, brushing, inspection, and sterilization in ethylene oxide. Validation testing was performed to assure compliance with accepted standards. RESULTS: With cleaning, the total mean bioburden for each of 3 batches of 10 randomly chosen devices was reduced from 754 to 10.1 colony-forming units. After sterilization with ethylene oxide, with 3 half-cycle and 3 full-cycle processes, none of the 90 biological indicator testers exhibited growth after 7 days. Through cleaning and sterilization, protein and hemoglobin concentrations were reduced from 99.2 to 1.42 µg/cm2 and from 21.4 to 1.03 µg/cm2, respectively. Mean total organic carbon residual was 1.44 parts per million (range 0.36 to 2.9 parts per million). Endotoxin concentration was not detectable at the threshold of <0.03 endotoxin units/ml or <3.0 endotoxin units/device. Cytotoxicity and intracutaneous reactivity tests met the standards set by the Association for Advancement of Medical Instrumentation and the International Organization for Standardization. CONCLUSIONS: CIEDs can be cleaned and sterilized according to a standardized protocol achieving a 12-log reduction of inoculated product, resulting in sterility assurance level of 10-6.

Comparison of the predictive value of exercise-induced ST depression versus exercise technetium-99m sestamibi single-photon emission computed tomographic imaging for detection of coronary artery disease in patients with left ventricular hypertrophy.

Scant knowledge exists regarding the significance of either additional ST depression in the presence of baseline depression or new stress-induced ST depression in patients with left ventricular (LV) hypertrophy. Accordingly, the purpose of this investigation is to determine whether the appearance and/or severity of ST abnormalities during exercise stress testing can accurately predict the prevalence of ischemic burden as measured by quantitative technetium-99m-sestamibi single-photon emission computed tomographic imaging in patients with LV hypertrophy. The results show that the presence of exercise ST-segment depression, as well as its magnitude, are not accurate predictors for identifying patients with coronary artery disease in the presence of electrocardiographic criteria for LV hypertrophy.

Risk factors and outcomes in patients with coronary artery aneurysms.

Previous small series have provided conflicting data on the association between coronary artery aneurysms and traditional cardiac risk factors, as well as limited information on patient outcomes. This investigation sought to determine whether the presence of coronary artery aneurysms has an adverse affect on patient outcomes. The results show that coronary aneurysms were an independent predictor of mortality, and overall 5-year survival in patients with aneurysms was only 71%. We believe that clinicians should aggressively monitor and modify coronary risk factors in patients with coronary aneurysms.

Feasibility of postmortem device acquisition for potential reuse in underserved nations.

OBJECTIVES: The purpose of the present study was to examine the feasibility and efficacy of a program to acquire devices with adequate battery life from crematories and funeral homes for potential reutilization in underserved nations. BACKGROUND: There exists a great health-care disparity between the industrialized world and underserved nations--specifically in the frequency of pacemaker implantation. METHODS: Flyers were mailed to all 1057 members of the Michigan Funeral Directors Association providing information to download a consent-for-explant form and request a postage-paid envelope from www.myheartyourheart.org in order to send explanted devices. Donated devices from funeral homes and crematories nationwide were also collected from World Medical Relief. Adequate battery life was defined as ≥75% or ≥4 years of estimated longevity. RESULTS: A total of 3176 devices (65% pacemakers, 21% implantable cardioverter-defibrillators [ICDs], 12% biventricular ICDs, and 3% biventricular pacemakers) were donated to the reutilization program. Five hundred fifty devices (21%; 95% confidence interval [CI] 19.4-22.6%) were found to have an acceptable battery life for reutilization. Among these devices, 313 were pacemakers (17.9%; 95% CI 16.1-19.8%), 118 were ICDs (17.9%; 95% CI 15.1-21.1%), 112 were biventricular ICDs (30.3%; 95% CI 25.6-35.2%), and 7 were biventricular pacemakers (17.3%; 95% CI 16.0-18.7%). CONCLUSIONS: Approximately 21% of donated devices and 30% of donated biventricular ICDs possess an adequate battery life for potential reuse. Device donations from funeral homes and crematories appear to be a potential resource for device reutilization for those in need in underserved nations.

Safety of pacemaker reuse: a meta-analysis with implications for underserved nations.

BACKGROUND: A large disparity in medical health care is clearly evident between developed and underserved nations in the field of cardiac electrophysiology, specifically pacemaker implantation. This study aimed to assess the safety of pacemaker reuse. METHODS AND RESULTS: A computerized search from January 1, 1970, to September 1, 2010, identified 18 studies with outcomes of pacemaker reuse. The primary outcome was pacemaker infection or device erosion as defined by each individual study protocol. Secondary end points were device malfunction defined as a defect in the structural or electric integrity of the pulse generator. Pooled individual patient data (n=2270) from 18 trials were included in the analysis. The proportion of patients in whom an infection developed after pacemaker reuse was 1.97% (1.15% to 3.00%). There was no significant difference in infection rate between pacemaker reuse and new device implantation (odds ratio, 1.31 [0.50 to 3.40], P=0.580). The proportion of patients in whom device malfunction developed after pacemaker reuse was 0.68% (0.27% to 1.28%). Compared with new device implantation, there was an increased risk for malfunction in the reuse group (odds ratio, 5.80 [1.93 to 17.47], P=0.002). This difference was mainly driven by abnormalities in set screws, which possibly occurred during device extraction, as well as nonspecific device "technical errors." CONCLUSIONS: This study suggests that pacemaker reuse has an overall low rate of infection and device malfunction and may be a safe and efficacious means of treating patients in underserved nations with symptomatic bradyarrhythmias and no other method of obtaining a device. However, the results also denote a higher rate of device malfunction as compared with new device implantation. Patients with highly symptomatic conduction disease may benefit from pacemaker reuse; however, they should be closely monitored for device malfunction, especially during implantation.