Step by step: How to perform a fluoroless cryoballoon ablation for atrial fibrillation.

INTRODUCTION: Pulmonary vein isolation is the cornerstone of ablation of atrial fibrillation. With widespread use of 3D Electroanatomic Mapping Systems and advances in intracardiac echo imaging, fluoroless ablation has been possible. METHODS: Fluoroless ablation with cryoballoon (CB), however, has not been widely performed because of the need to prove occlusion of the vein with contrast dye and fluoroscopy. RESULTS AND CONCLUSION: In this step-by-step guide, the authors will show how a CB ablation can be performed without the use of fluoroscopy.

Procedural and short-term results of electroanatomic-mapping-guided ganglionated plexus ablation by first-time operators: A multicenter study.

INTRODUCTION: Single-center observational studies have shown promising results with fragmented electrogram (FE)-guided ganglionated plexus (GP) ablation in patients with vagally mediated bradyarrhythmia (VMB). We aimed to compare the acute procedural characteristics during FE-guided GP ablation in patients with VMB performed by first-time operators and those of a single high-volume operator. METHODS AND RESULTS: This international multicenter cohort study included data collected over 2 years from 16 cardiac hospitals. The primary operators were classified according to their prior GP ablation experience: a single high-volume operator who had performed > 50 GP ablation procedures (Group 1), and operators performing their first GP ablation cases (Group 2). Acute procedural characteristics and syncope recurrence were compared between groups. Forty-seven consecutive patients with VMB who underwent FE-guided GP ablation were enrolled, n = 31 in Group 1 and n = 16 in Group 2. The mean number of ablation points in each GP was comparable between groups. The ratio of positive vagal response during ablation on the left superior GP was higher in Group 1 (90.3% vs. 62.5%, p = .022). Ablation of the right superior GP increased heart rate acutely without any vagal response in 45 (95.7%) cases. The procedure time was longer in group 2 (83.4 ± 21 vs. 118.0 ± 21 min, respectively, p < .001). Over a mean follow-up duration of 8.0 ± 3 months (range 2-24 months), none of the patients suffered from syncope. CONCLUSION: This multi-center pilot study shows for the first time the feasibility of FE-guided GP ablation across a large group of procedure-naïve operators.

The Advanced Application of Intracardiac Echocardiography for Cardiac Electrophysiology Ablation Procedures.

PURPOSE OF REVIEW: The advanced use of intracardiac echocardiography (ICE) is both a significant leap forward and an underutilized and unrealized innovation for electrophysiological (EP) procedures [1]. ICE can inform operators of complex anatomic heterogeneity as well as close anatomic relationships beyond fluoroscopy and even electroanatomic mapping. We will review the myriad advantages of advanced ICE application to EP ablation procedures. RECENT FINDINGS: While 3D mapping has significantly advanced diagnosis and treatment efficiency for ablation procedures quite rapidly, widespread adoption of advanced ICE techniques beyond a supplemental technology has not been as swift. The advanced application of ICE has the ability to vastly improve the safety of EP procedures while reducing or eliminating required fluoroscopic guidance in many aspects [2]. The advanced application of ICE offers many opportunities to improve procedural efficacy and safety. Further research should focus on quantifying these benefits and understanding how best to disseminate these techniques for broader electrophysiological practice.

Cardioneuroablation for the management of patients with recurrent vasovagal syncope and symptomatic bradyarrhythmias: the CNA-FWRD Registry.

BACKGROUND: Cardioneuroablation has been emerging as a potential treatment alternative in appropriately selected patients with cardioinhibitory vasovagal syncope (VVS) and functional AV block (AVB). However the majority of available evidence has been derived from retrospective cohort studies performed by experienced operators. METHODS: The Cardioneuroablation for the Management of Patients with Recurrent Vasovagal Syncope and Symptomatic Bradyarrhythmias (CNA-FWRD) Registry is a multicenter prospective registry with cross-over design evaluating acute and long-term outcomes of VVS and AVB patients treated by conservative therapy and CNA. RESULTS: The study is a prospective observational registry with cross-over design for analysis of outcomes between a control group (i.e., behavioral and medical therapy only) and intervention group (Cardioneuroablation). Primary and secondary outcomes will only be assessed after enrollment in the registry. The follow-up period will be 3 years after enrollment. CONCLUSIONS: There remains a lack of prospective multicentered data for long-term outcomes comparing conservative therapy to radiofrequency CNA procedures particularly for key outcomes including recurrence of syncope, AV block, durable impact of disruption of the autonomic nervous system, and long-term complications after CNA. The CNA-FWRD registry has the potential to help fill this information gap.

Advancing global equity in cardiac care as cardiac implantable electronic device reuse comes of age.

A nation's health and economic development are inextricably and synergistically connected. Stark differences exist between wealthy and developing nations in the use of cardiac implantable electronic devices (CIEDs). Cardiovascular disease is now the leading cause of death in low- and middle-income countries (LMIC), with a significant burden from rhythm-related diseases. As science, technology, education, and regulatory frameworks have improved, CIED recycling for exportation and reuse in LMIC has become possible and primed for widespread adoption. In our manuscript, we outline the science and regulatory pathways regarding CIED reuse. We propose a pathway to advance this technology that includes creating a task force to establish standards for CIED reuse, leveraging professional organizations in areas of need to foster the professional skills for CIED reuse, collaborating with regulatory agencies to create more efficient regulatory expectations and bring the concept to scale, and establishing a global CIED reuse registry for quality assurance and future science.

Acute Safety and Efficacy of Fluoroless Cryoballoon Ablation for Atrial Fibrillation.

Pulmonary vein isolation (PVI) is widely used for the ablation of atrial fibrillation, with prior reports suggesting good efficacy. Due to the widespread use of three-dimensional electroanatomic mapping systems and advances in intracardiac echocardiography, fluoroless ablation has been made possible. Fluoroless ablation with a cryoballoon (CB), however, has not been widely performed because of the need to prove occlusion of the vein with contrast dye and fluoroscopy. The objective of this study is to show that CB ablation can be performed safely and effectively without fluoroscopy. A dual-center, case-control study was performed of patients undergoing CB PVI with a fluoroless approach and a control group with traditional fluoroscopic techniques. The absence of color-flow Doppler signals around the periphery of the CB on intracardiac echocardiography and an increase in mean pressure by 5 mmHg, loss of the A-wave, and an increase in the V-wave as measured with continuous-wave pressure monitoring were adopted as indicators of vein occlusion in the absence of fluoroscopy. Temperature at 30 seconds, minimum temperature, time to isolation, procedure length, and complications were evaluated. During the study period of November 15, 2018 to November 15, 2019, a total of 100 patients underwent CB PVI at the participating centers. A total of 50 patients were enrolled in the fluoroless arm [35 men (70%), mean age: 64.9 ± 12 years, mean left atrium size: 44.2 ± 16 mL/m2, left ventricular ejection fraction: 61% ± 5%], while 50 patients were enrolled in the control arm with similar characteristics. Four hundred forty-one 441 PVs were evaluated in the study cohort compared to 339 PVs in the control arm. When comparing fluoroless and traditional techniques, the mean temperature at 30 seconds was -31.7°C ± 6°C versus -32.8°C ± 5°C (p = 0.037), the minimum temperature was -47.4°C ± 6°C versus -47.7°C ± 9°C (p = 0.677), the time to isolation was 56.8 ± 28 seconds versus 74.8 ± 45 seconds (p = 0.212), and the procedure time was 102.2 ± 27.3 seconds versus 104.5 ± 16.9 seconds (p = 0.6436). Ultimately, this proof-of-concept study revealed that fluoroless ablation can be performed with success and efficiency outcomes similar to those of a traditional ablation approach. This suggests that the ablation of atrial fibrillation with CB can be performed safely and effectively without the use of fluoroscopy by experienced operators.

A Blueprint for Productive Maintenance of Certification, But Is the American Board of Internal Medicine up to the Challenge?

The future of the American Board of Internal Medicine Maintenance of Certification (MOC) program is at a crossroads. The current MOC program lacks a clear visible mission, adds to modern health care's onerous bureaucracy, and thus pulls physicians from the most important humanistic aspects of their profession. The aim of the MOC program should be to promote the best patient care by ensuring certified physicians maintain core skills through continuous education and evaluation. The program should focus on education and be designed with the rigorous obligations of practicing physicians in mind. Moving forward, the American Board of Internal Medicine should cocreate MOC with the physician community and apply innovative adult education techniques. Over time, data-driven methods and member feedback should be used to provide continuous program improvement. This review describes the origins of the current state of MOC, explores its evidence base, provides examples of model programs for the maintenance of complex professional skills, and outlines guiding principles for the future of MOC.

Postinfarction Myocardial Calcifications on Cardiac Computed Tomography: Implications for Mapping and Ablation in Patients With Nontolerated Ventricular Tachycardias.

BACKGROUND: Postinfarction ventricular tachycardia (VT) generally involves myocardial fibers surrounded by scar. Calcification of scar tissue has been described, but the relationship between calcifications within endocardial scar and VTs is unclear. The purpose of this study was to assess the prevalence of myocardial calcifications as detected by cardiac computed tomography (CT) and the benefit for mapping and ablation focusing on nontolerated VTs. METHODS: Fifty-six consecutive postinfarction patients had a cardiac CT performed before a VT ablation procedure. Another 56 consecutive patients with prior infarction without VT who had cardiac CTs served as a control group. RESULTS: Myocardial calcifications were identified in 39 of 56 patients (70%) in the postinfarction group with VT, compared with 6 of 56 patients (11%) in the control group without VT. Calcifications were associated with VT when compared with a control group. A calcification volume of 0.538 cm3 distinguished patients with calcification-associated VT from patients without calcification-associated VTs (area under the curve, 0.87; sensitivity, 0.87; specificity, 0.88). Myocardial calcifications corresponded to areas of electrical nonexcitability and formed a border for reentry circuits for 49 VTs (33% of all VTs for which target sites were identified) in 24 of 39 patients (62%) with myocardial calcifications. A nonconfluent calcification pattern was associated with VT target sites independent of calcification volume ( P=0.01). CONCLUSIONS: Myocardial calcifications detected by cardiac CT in patients with prior infarction are associated with VT. The calcifications correspond to areas of unexcitability and represent a fixed boundary of reentry circuits that can be visualized by CT. Calcifications correspond to effective ablation sites in >1/3 of patients with postinfarction VT.

Antiarrhythmic drug therapy and all-cause mortality after catheter ablation of atrial fibrillation: A propensity-matched analysis.

BACKGROUND: It is not clear if antiarrhythmic drug therapy (AAD) after catheter ablation (CA) of atrial fibrillation (AF) increases mortality. OBJECTIVE: To determine whether there is an association between AAD therapy and mortality after CA of AF. METHODS: There were 3624 consecutive patients with AF (mean age: 59 ± 11 years, women: 27%, paroxysmal AF: 58%). An AAD was used in 2253 patients (62%, AAD group) for a mean duration of 1.3 ± 0.8 years, during a mean follow-up of 6.7 ± 2.2 years after CA of AF. Using propensity score matching, with every 2 patients using an AAD matched to 1 patient who did not use AAD (NO-AAD group), Cox regression models were utilized to assess the association between AAD use (as a time-variable covariate) and all-cause mortality. RESULTS: There were a total of 50 deaths (2.2%) in the AAD and 62 deaths (4.5%) in the NO-AAD groups, respectively (P = .02). At the time of death, 46 of 50 patients (92%) who died in the AAD cohort were still using an AAD (P = .21, compared to baseline use). On multivariate analysis, although the risk of death was not statistically significant between the AAD and NO-AAD cohorts, there was a trend towards mortality benefit with AAD therapy (hazard ratio [HR]: 0.66, 95% confidence interval [CI]: 0.43-1.00, P = .05), regardless of the rhythm or anticoagulation status. CONCLUSION: AAD use after CA of AF is not associated with an increased risk of mortality, suggesting that when carefully chosen and monitored, AADs appear to be safe after CA of AF.

Exploring the Healthcare Value of Percutaneous Coronary Intervention: Appropriateness, Outcomes, and Costs in Michigan Hospitals.

BACKGROUND: Assessments of healthcare value have largely focused on measuring outcomes of care at a given level of cost with less attention paid to appropriateness. However, understanding how appropriateness relates to outcomes and costs is essential to determining healthcare value. METHODS AND RESULTS: In a retrospective cohort study design, administrative data from fee-for-service Medicare patients undergoing percutaneous coronary intervention (PCI) in Michigan hospitals between June 30, 2010, and December 31, 2014, were linked with clinical data from a statewide PCI registry to calculate hospital-level measures of (1) appropriate use criteria scores, (2) 90-day risk-standardized readmission and mortality rates, and (3) 90-day risk-standardized episode costs. We then used Spearman correlation coefficients to assess the relationship between these measures. A total of 29 839 PCIs were performed at 33 PCI hospitals during the study period. A total of 13.3% were for ST-segment-elevation myocardial infarction, 25.0% for non-ST-segment-elevation myocardial infarction, 47.1% for unstable angina, 9.8% for stable angina, and 4.7% for other. The overall hospital-level mean appropriate use criteria score was 8.4±0.2. Ninety-day risk-standardized readmission occurred in 23.7%±3.7% of cases, 90-day risk-standardized mortality in 4.3%±0.6%, and mean risk-standardized episode costs were $26 159±$1074. Hospital-level appropriate use criteria scores did not correlate with 90-day readmission, mortality, or episode costs. CONCLUSIONS: Among Medicare patients undergoing PCI in Michigan, we found hospital-level appropriate use criteria scores did not correlate with 90-day readmission, mortality, or episode costs. This finding suggests that a comprehensive understanding of healthcare value requires multidimensional consideration of appropriateness, outcomes, and costs.

Protamine to expedite vascular hemostasis after catheter ablation of atrial fibrillation: A randomized controlled trial.

BACKGROUND: There are no randomized controlled studies of the efficacy and safety of protamine to reverse anticoagulant effects of heparin after catheter ablation (CA) of atrial fibrillation (AF). OBJECTIVE: The purpose of this study was to determine the efficacy and safety of protamine to expedite vascular hemostasis and ambulation after CA of AF. METHODS: CA to eliminate AF (n = 139) or left atrial flutter (n = 11) was performed in 150 patients using radiofrequency catheter ablation (n = 112) or cryoballoon ablation (n = 38). CA was performed under uninterrupted anticoagulation with warfarin in 28 patients or after skipping a single dose of a novel oral anticoagulant in 122 patients who were randomized to receive protamine (n = 77) or to the control group (n = 73). Baseline and procedural characteristics were similar between the 2 groups. Hemostasis was achieved manually once the activated clotting time returned to preprocedural values. RESULTS: The maximum activated clotting time during CA was 359 ± 31 and 359 ± 29 seconds in the protamine and control groups, respectively (P = .91). The time to hemostasis was 123 ± 95 minutes in the protamine group and 260 ± 70 minutes in the control group (P < .001). The time to ambulation was 316 ± 80 and 480 ± 92 minutes in the protamine and control groups, respectively (P < .001). There were no differences in the rates of major or minor vascular access complications or thromboembolic events (P > .05). CONCLUSION: Protamine expedites vascular hemostasis and time to ambulation by ∼3 hours after CA of AF without an increase in the risk of vascular or thromboembolic complications.

Association of caspase-1 polymorphisms with Chagas cardiomyopathy among individuals in Santa Cruz, Bolivia.

INTRODUCTION:: Trypanosoma cruzi (Tc) infection is usually acquired in childhood in endemic areas, leading to Chagas disease, which progresses to Chagas cardiomyopathy in 20-30% of infected individuals over decades. The pathogenesis of Chagas cardiomyopathy involves the host inflammatory response to T. cruzi, in which upstream caspase-1 activation prompts the cascade of inflammatory chemokines/cytokines, cardiac remodeling, and myocardial dysfunction. The aim of the present study was to examine the association of two caspase-1 single nucleotide polymorphisms (SNPs) with cardiomyopathy. METHODS:: We recruited infected (Tc+, n = 149) and uninfected (Tc-, n = 87) participants in a hospital in Santa Cruz, Bolivia. Cardiac status was classified (I, II, III, IV) based on Chagas cardiomyopathy-associated electrocardiogram findings and ejection fractions on echocardiogram. Genotypes were determined using Taqman probes via reverse transcription-polymerase chain reaction of peripheral blood DNA. Genotype frequencies were analyzed according to three inheritance patterns (dominant, recessive, additive) using logistic regression adjusted for age and sex. RESULTS:: The AA allele for the caspase-1 SNP rs501192 was more frequent in Tc+ cardiomyopathy (classes II, III, IV) patients compared to those with a normal cardiac status (class I) [odds ratio (OR) = -2.18, p = 0.117]. This trend approached statistical significant considering only Tc+ patients in class I and II (OR = -2.64, p = 0.064). CONCLUSIONS:: Caspase-1 polymorphisms may play a role in Chagas cardiomyopathy development and could serve as markers to identify individuals at higher risk for priority treatment.

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.