Real-life Clinical Outcomes of Low-voltage Isolation and Spatiotemporal Dispersion Ablation Strategies for Persistent Atrial Fibrillation.

Multiple techniques have been developed in addition to pulmonary vein isolation (PVI) to improve the outcomes of catheter ablation in patients with persistent atrial fibrillation (AF). We sought to evaluate the long-term efficacy of alternative techniques used in our laboratory for the treatment of persistent AF, including spatiotemporal dispersion (SD) and low-voltage isolation (LVI). Consecutive patients with persistent AF who underwent catheter ablation with the studied techniques between July 2016 and December 2019 were included in the study. PVI alone was compared with PVI plus SD and PVI plus LVI in terms of long-term freedom from atrial tachycardia (AT) and AF recurrence. Follow-up data were obtained from clinical records and hospital visits, which included a 7-day Holter monitor and electrocardiograms. The study was approved by the institutional review board of Rhode Island Hospital. A total of 382 patients underwent catheter ablation at our institution during the study period. One hundred seventy-two patients had paroxysmal AF and were excluded from the study. The remaining 210 patients had persistent AF and were included in the study. One hundred and three patients underwent PVI alone, while 48 had the addition of LVI and 59 had SD. Additionally, freedom from AT/AF recurrence at 18 months was 68% in the group that underwent LVI, 49% in the SD group, and 40% in the group that underwent PVI alone (log-rank P = .014). Freedom from AF recurrence was 74% in the LVI group, 71% in the SD group, and 43% in the PVI-alone group (log-rank P = .002). On multivariate Cox regression, LVI and left atrial size were found to be independent predictors of recurrence (hazard ratio, 0.39; 95% confidence interval, 0.206-0.760; P = .005 and hazard ratio, 1.4; 95% confidence interval, 1.105-1.923; P = .008, respectively). LVI and SD in addition to PVI were associated with greater freedom from AT/AF recurrence at 18 months compared to PVI alone.

Interference by Modern Smartphones and Accessories with Cardiac Pacemakers and Defibrillators.

PURPOSE OF REVIEW: The risk of cardiac implantable electronic device (CIED) interference from cell phones was previously thought to be low based on older studies. Current generation of smartphones have incorporated more magnets for optimization of wireless charging, attachment of accessories, and convenience functionalities. These magnets have the potential to cause CIEDs to inadvertently revert into magnet mode. The purpose of this review is to summarize recent findings on smartphones and their accessories causing interference on CIEDs. RECENT FINDINGS: Recent reports have demonstrated that the iPhone 12 series and accessories have the capability to cause CIED magnetic interference. Current generation of smartphones, smartwatches, wireless headphones, and accessories have the potential to cause CIEDs to revert into magnet mode in both in vivo and ex vivo experiments. The risk of a clinically significant event is unlikely as long as the Food and Drug Administration (FDA) recommendations are followed; keeping smartphones and accessories at least six inches away from CIEDs.

Magnetic Interference on Cardiac Implantable Electronic Devices From Apple iPhone MagSafe Technology.

Background Magnet wireless charging is being utilized increasingly in current generation smartphones. Apple's MagSafe is a proprietary wireless charging technology with an array of magnets that has the capacity to generate magnet fieldstrength >50 gauss (G). We hypothesize that there is clinically significant magnet interference caused by Apple's MagSafe technology on cardiac implantable electronic devices (CIED). Methods and Results This study has an in vivo and an ex vivo component. The in vivo component consists of consecutive patients who presented to the electrophysiology laboratory with previously implanted CIEDs. The iPhone 12 Pro Max was directly placed on the skin over the pocket of these patients and the effect was studied by device interrogation. For the ex vivo component of the study, CIEDs from major device companies were tested for magnetic interference caused by iPhone 12 Pro Max through unopened packages. We found that iPhone 12 Pro Max resulted in clinically identifiable magnet interference in 3/3 (100%) participants in vivo and in 8/11 (72.7%) devices ex vivo. Conclusions Apple's iPhone 12 Pro Max MagSafe technology can cause magnet interference on CIEDs and has the potential to inhibit lifesaving therapy.

A New WATCHMAN Sizing Algorithm Utilizing Cardiac CTA.

BACKGROUND: The WATCHMAN left atrial appendage (LAA) occlusion device has emerged as an alternative for anticoagulation in patients with non-valvular atrial fibrillation who cannot tolerate oral anticoagulation therapy. Cardiac computed tomography (CTA) is increasingly being utilized to guide WATCHMAN device sizing, however no consensus algorithm exists. We present our experience with a new cardiac CTA LAA ostium area based sizing algorithm. METHODS: This is a single center, prospective study analyzing consecutive patients who underwent cardiac CTA and WATCHMAN device implantation between March 2017 and October 2019 at University Hospitals Cleveland Medical Center. Patients baseline characteristics, procedural data, and clinical outcomes were collected and analyzed. RESULTS: 115 patients were included in our study. The mean age of our population was 76.5 years ±8.3 years. 70.4% of our patients had preserved ejection fraction. The predominant indication for device implantation was gastrointestinal bleeding in 57.4% of patients. The mean CHADSVASC score was 4.68 ± 1.4. The procedure success rate was 99.1% and the mean number of device used per case of 1.15 ± 0.4 devices. Our CTA LAA ostium area based sizing algorithm accurately predicted the final deployed WATCHMAN device size in 95.6% of cases. CONCLUSION: Our study demonstrates that cardiac CTA LAA ostium area based sizing algorithm is highly accurate at predicting WATCHMAN device size and demonstrates excellent clinical outcomes with lower device utilization per case than what is reported in literature.

Transcatheter Valve Implantation for Failed Surgical Aortic and Mitral Bioprostheses: A Single-Center Experience.

OBJECTIVES: We share our center's experience with the use of transcatheter valvular therapies in the setting of failed bioprostheses. BACKGROUND: As medicine continues to advance, the lifespan of individuals continues to increase, and current surgical valvular therapies begin to degrade prior to a person's end of life. It is important to evaluate the efficacy and durability of transcatheter valves within failed surgical bioprostheses. METHODS: Baseline characteristics, periprocedural complications, and long-term outcomes were collected and assessed in patients who received transcatheter valves for failing surgical aortic valve bioprostheses and mitral valve and ring bioprostheses from March 2011 to July 2018. RESULTS: From our cohort of 1048 patients, we identified 45 individuals (4.3%) who underwent transcatheter replacement of a failed bioprosthetic valve or ring. Mean age at presentation was 80.8 ± 10.7 years and 75.5 ± 9.3 years, mean STS score was 9.3 ± 5.1 and 13.3 ± 8.7, and mean time to failure was 12.0 ± 5.2 years and 7.3 ± 4.5 years for aortic and mitral positions, respectively. At 1 year, time to event analysis suggested a 16.4% mortality rate for aortic replacement and 12.8% mortality rate for mitral replacement. CONCLUSIONS: We demonstrate outcomes from one of the largest single-center United States based cohorts of transcatheter replacements of failed surgical bioprostheses. Our center has demonstrated that it is feasible to pursue the replacement of failed surgical bioprostheses in the aortic and mitral positions with transcatheter valves given appropriate patient selection.

Risk Prediction Model for Cardiac Implantable Electronic Device Implantation After Transcatheter Aortic Valve Replacement.

OBJECTIVES: The aim of this study was to develop and validate a risk prediction model for high-grade atrioventricular block requiring cardiac implantable electronic device (CIED) implantation after transcatheter aortic valve replacement (TAVR). BACKGROUND: High-grade atrioventricular block requiring CIED remains a significant sequelae following TAVR. Although several pre-operative characteristics have been associated with the risk of post-operative CIED implantation, an accurate and validated risk prediction model is not established yet. METHODS: This was a single center, retrospective study of consecutive patients who underwent TAVR from March 10, 2011, to October 8, 2018. This cohort sample was randomly divided into a derivation cohort (group A) and a validation cohort (group B). A scoring system for risk prediction of post-TAVR CIED implantation was devised using logistic regression estimates in group A and the calibration and validation were done in group B. RESULTS: A total of 1,071 patients underwent TAVR during the study period. After excluding pre-existing CIED, a total of 888 cases were analyzed (group A: 507 and group B: 381). Independent predictive variables were as follows: self-expanding valve (1 point), hypertension (1 point), pre-existing first-degree atrioventricular block (1 point), and right bundle branch block (2 points). The resulting score was calculated from the total points. The internal validation in group B showed an ideal linear relationship in calibration plot (R2 = 0.933) and a good predictive accuracy (area under the curve: 0.693; 95% confidence interval: 0.627 to 0.759). CONCLUSIONS: This prediction model accurately predicts post-operative risk of CIED implantation with simple pre-operative parameters.

Real World Utilization of Computed Tomography Derived Fractional Flow Reserve: Single Center Experience in the United States.

BACKGROUND: Fractional flow reserve derived from computed tomography (FFRct) has shown higher accuracy for detection of significant coronary artery disease (CAD) compared to coronary computed tomography angiography (CCTA). The performance of a combined comprehensive qualitative interpretation of both CCTA and FFRct in patient management is unknown. We aimed to explore the clinical application of this combined approach. METHODS: We retrospectively reviewed cases referred to FFRct testing at our institution over a one-year period. Patients had documentation of whether invasive coronary angiography (ICA) was performed and revascularization were needed. Interpretations and recommendations of the adopted comprehensive approach (C-FFRct), that took into account focal versus diffuse disease, depth of ischemia and myocardium at risk, were compared to those of CCTA (binary > 50% stenosis) alone and FFRct binary approach (FFRct ≤ 0.8). C-FFRct performance was measured against the decision made upon revascularization. RESULTS: A total of 207 cases were referred to FFRct testing, 163 (79%) accepted and 44 (21%) rejected for quality. C-FFRct changed interpretations and recommendations of 39 (24%) and 14 (9%) CCTA and FFRct, respectively. ICA was deferred in 32 (59%) and 13 (32%) cases; whereas ICA referral rate was 7 (6%) and 1 (0.8%) cases, based on CCTA and FFRct, respectively. No major cardiac events were observed during follow up time (median = 6 months). C-FFRct sensitivity, specificity, and accuracy compared to decision upon revascularization were 89%, 79% and 82%. C-FFRct number needed to treat was 4, and 6, compared to CCTA and FFRct, respectively. CONCLUSION: FFRct is a feasible tool to improve the diagnostic performance of CCTA in CAD real-world workup. However, qualitative interpretation of the FFRct report combined with CCTA findings may yield more impactful results on patient management. Further prospective studies are warranted to validate the application of this approach and better define its components.

Simultaneous Venoarterial Extracorporeal Membrane Oxygenation and Percutaneous Left Ventricular Decompression Therapy with Impella Is Associated with Improved Outcomes in Refractory Cardiogenic Shock.

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) has been used for refractory cardiogenic shock; however, it is associated with increased left ventricular afterload. Outcomes associated with the combination of a percutaneous left ventricular assist device (Impella) and VA-ECMO remains largely unknown. We retrospectively reviewed patients treated for refractory cardiogenic shock with VA-ECMO (2014-2016). The primary outcome was all-cause mortality within 30 days of VA-ECMO implantation. Secondary outcomes included duration of support, stroke, major bleeding, hemolysis, inotropic score, and cardiac recovery. Outcomes were compared between the VA-ECMO cohort and VA-ECMO + Impella (ECPELLA cohort). Sixty-six patients were identified: 36 VA-ECMO and 30 ECPELLA. Fifty-eight percent of VA-ECMO patients (n = 21) had surgical venting, as compared to 100% of the ECPELLA cohort (n = 30) which had Impella (±surgical vent). Both cohorts demonstrated relatively similar baseline characteristics except for higher incidence of ST-elevation myocardial infarction (STEMI) and percutaneous coronary intervention (PCI) in the ECPELLA cohort. Thirty-day all-cause mortality was significantly lower in the ECPELLA cohort (57% vs. 78%; hazard ratio [HR] 0.51 [0.28-0.94], log rank p = 0.02), and this difference remained intact after correcting for STEMI and PCI. No difference between secondary outcomes was observed, except for the inotrope score which was greater in VA-ECMO group by day 2 (11 vs. 0; p = 0.001). In the largest US-based retrospective study, the addition of Impella to VA-ECMO for patients with refractory cardiogenic shock was associated with lower all-cause 30 day mortality, lower inotrope use, and comparable safety profiles as compared with VA-ECMO alone.

Impact of residual coronary atherosclerosis on transfemoral transcatheter aortic valve replacement.

OBJECTIVES: This study reports on the clinical effects of complete vs incompletely revascularized coronary artery disease on transcatheter aortic valve replacement (TAVR). BACKGROUND: There is a high prevalence of active coronary artery disease (CAD) in patients undergoing TAVR but preemptive revascularization remains controversial. METHODS: Patients were categorized into three cohorts: complete revascularization (CR), incomplete revascularization of a major epicardial artery (IR Major), and incomplete revascularization of a minor epicardial artery only (IR Minor). When feasible, SYNTAX scoring was performed for exploratory analysis. Analyses were performed using Cox proportional hazard models and Kaplan-Meier method. RESULTS: A total of 323 patients with active CAD were included. Adjusted outcomes showed that patients with IR Major had increased incidence of acute myocardial infarction (AMI) or revascularization compared with those in the CR cohort (HR 3.72, P = 0.048). No difference was noted in all-cause mortality or all-cause readmission rates. Exploratory secondary analysis with residual SYNTAX scores showed a significant interaction between disease burden and AMI/revascularization, as well as all-cause readmission. All-cause mortality remained unaffected based on residual SYNTAX scores. CONCLUSIONS: This is a retrospective single-center study reporting on pre-TAVR revascularization outcomes in patients with active CAD. In this analysis, we found that patients undergoing TAVR benefited from achieving complete revascularization to abate future incidence of AMI/revascularization. Despite this finding, all-cause mortality remained unaffected. Future efforts should focus on the role of functional assessment of the coronaries, as well as the long-term effects of complete revascularization in a larger patient cohort.

Impact of Right Ventricular Pacing in Patients Who Underwent Implantation of Permanent Pacemaker After Transcatheter Aortic Valve Implantation.

Atrioventricular conduction disturbances requiring implantation of permanent pacemaker (PPM) are a common complication following transcatheter aortic valve implantation (TAVI). Previous registry data are conflicting but suggestive of an increased risk in heart failure admissions in the post-TAVI PPM cohort. Given the expanding use of TAVI, the present study evaluates the effects of chronic right ventricular pacing (RV pacing) in post-TAVI patients. This is a single-center study of 672 patients who underwent TAVI from 2011 to 2017 of which 146 underwent PPM. Follow-up 1-year post-TAVI outcome data were available for 55 patients and were analyzed retrospectively. Patients who underwent PPM were more likely to have heart failure admissions (17.1% vs 10.1%; hazard ratio [HR] 1.70; 95% confidence interval [CI] 1.10 to 2.64; p 0.019) and a trend toward increased mortality (21.9% vs 15.4%; HR 1.42; 95% CI 0.99 to 2.05; p 0.062). At 1-year follow-up, 30 of 55 (54.5%) patients demonstrated >40% RV pacing. Compared with patients who had <40% RV pacing, those with >40% RV pacing were more likely to have heart failure admissions (8% vs 40%; HR 5.0; 95% CI 1.23 to 20.27; p 0.007) and demonstrated a trend toward increased mortality (12% vs 33.3%; HR 2.78; 95% CI 0.86 to 9.00; p 0.064). This is suggestive that the post-TAVI PPM cohort is particularly sensitive to chronic RV pacing.