New-generation electronic appliances and cardiac implantable electronic devices: a systematic literature review of mechanisms and in vivo studies

INTRODUCTION

Cardiac implantable electronic device (CIED) functions are susceptible to electromagnetic interference (EMI) from electromagnetic fields (EMF). Data on EMI risks from new-generation electronic appliances (EA) are limited.

OBJECTIVE

We performed a systematic literature review on the mechanisms of EMI, current evidence, and recently published trials evaluating the effect of EMF on CIEDs from electric vehicles (EV), smartphone, and smartwatch technology and summarize its safety data.

METHODS

Electronic databases, including PubMed and EMBASE, were searched for in vivo studies evaluating EMF strength and incidence between CIEDs and commercial EVs, new-generation smartphones, and new-generation smartwatches.

RESULTS

A total of ten studies (three on EVs, five on smartphones, one on smartphones, one on smartphones and smartwatches) were included in our systematic review. There was no report of EMI incidence associated with EVs or smartwatches. Magnet-containing smartphones (iPhone 12) can cause EMI when placed directly over CIEDs - thereby triggering the magnet mode; otherwise, no report of EMI was observed with other positions or smartphone models.

CONCLUSION

Current evidence suggests CIED recipients are safe from general interaction with EVs/HEVs, smartphones, and smartwatches. Strictly, results may only be applied to commercial brands or models tested in the published studies. There is limited data on EMI risk from EVs wireless charging and smartphones with MagSafe technology.

Severity of Ischemic Stroke After Left Atrial Appendage Closure vs Nonwarfarin Oral Anticoagulants

BACKGROUND

Strokes after left atrial appendage closure (LAAC) prophylaxis are generally less severe than those after warfarin prophylaxis-thought to be secondary to more hemorrhagic strokes with warfarin. Hemorrhagic strokes are similarly infrequent with direct oral anticoagulant (DOAC) prophylaxis, so the primary subtype after either LAAC or DOAC prophylaxis is ischemic stroke (IS).

OBJECTIVES

The purpose of this study was to compare the severity of IS using the modified Rankin Scale in atrial fibrillation patients receiving prophylaxis with DOACs vs LAAC.

METHODS

A retrospective analysis was performed of consecutive patients undergoing LAAC at 8 centers who developed an IS (ISLAAC) compared with contemporaneous consecutive patients who developed IS during treatment with DOACs (ISDOAC). The primary outcome was disabling/fatal stroke (modified Rankin Scale 3-5) at discharge and 3 months later.

RESULTS

Compared with ISDOAC patients (n = 322), ISLAAC patients (n = 125) were older (age 77.2 ± 13.4 years vs 73.1 ± 11.9 years; P = 0.002), with higher HAS-BLED scores (3.0 vs 2.0; P = 0.004) and more frequent prior bleeding events (54.4% vs 23.6%; P < 0.001), but similar CHA2DS2-VASc scores (5.0 vs 5.0; P = 0.28). Strokes were less frequently disabling/fatal with ISLAAC than ISDOAC at both hospital discharge (38.3% vs 70.3%; P < 0.001) and 3 months later (33.3% vs 56.2%; P < 0.001). Differences in stroke severity persisted after propensity score matching. By multivariate regression analysis, ISLAAC was independently associated with fewer disabling/fatal strokes at discharge (OR: 0.22; 95% CI: 0.13-0.39; P < 0.001) and 3 months (OR: 0.25; 95% CI: 0.12-0.50; P < 0.001), and fewer deaths at 3 months (OR: 0.28; 95% CI: 0.12-0.64; P < 0.001).

CONCLUSIONS

Ischemic strokes in patients with atrial fibrillation are less often disabling or fatal with LAAC than DOAC prophylaxis.

Impact of Left Atrial Posterior Wall Ablation During Pulsed-Field Ablation for Persistent Atrial Fibrillation

BACKGROUND

Pulmonary vein isolation (PVI) alone is insufficient to treat many patients with persistent atrial fibrillation (PersAF). Adjunctive left atrial posterior wall (LAPW) ablation with thermal technologies has revealed lack of efficacy, perhaps limited by the difficulty in achieving lesion durability amid concerns of esophageal injury.

OBJECTIVES

This study aims to compare the safety and effectiveness of PVI + LAPW ablation vs PVI in patients with PersAF using pulsed-field ablation (PFA).

METHODS

In a retrospective analysis of the MANIFEST-PF (Multi-National Survey on the Methods, Efficacy, and Safety on the Post-approval Clinical Use of Pulsed Field Ablation) registry, we studied consecutive PersAF patients undergoing post-approval treatment with a pentaspline PFA catheter. The primary effectiveness outcome was freedom from any atrial arrhythmia of ≥30 seconds. Safety outcomes included the composite of acute and chronic major adverse events.

RESULTS

Of the 547 patients with PersAF who underwent PFA, 131 (24%) received adjunctive LAPW ablation. Compared to PVI-alone, patients receiving adjunctive LAPW ablation were younger (65 vs 67 years of age, P = 0.08), had a lower CHA2DS2-VASc score (2.3 ± 1.6 vs 2.6 ± 1.6, P = 0.08), and were more likely to receive electroanatomical mapping (48.1% vs 39.0%, P = 0.07) and intracardiac echocardiography imaging (46.1% vs 17.1%, P < 0.001). The 1-year Kaplan-Meier estimate for freedom from atrial arrhythmias was not statistically different between groups in the full (PVI + LAPW: 66.4%; 95% CI: 57.6%-74.4% vs PVI: 73.1%; 95% CI: 68.5%-77.2%; P = 0.68) and propensity-matched cohorts (PVI + LAPW: 71.7% vs PVI: 68.5%; P = 0.34). There was also no significant difference in major adverse events between the groups (2.2% vs 1.4%, respectively, P = 0.51).

CONCLUSIONS

In patients with PersAF undergoing PFA, as compared to PVI-alone, adjunctive LAPW ablation did not improve freedom from atrial arrhythmia at 12 months.

Clinical Outcomes by Sex After Pulsed Field Ablation of Atrial Fibrillation

Importance

Previous studies evaluating the association of patient sex with clinical outcomes using conventional thermal ablative modalities for atrial fibrillation (AF) such as radiofrequency or cryoablation are controversial due to mixed results. Pulsed field ablation (PFA) is a novel AF ablation energy modality that has demonstrated preferential myocardial tissue ablation with a unique safety profile.

Objective

To compare sex differences in patients undergoing PFA for AF in the Multinational Survey on the Methods, Efficacy, and Safety on the Postapproval Clinical Use of Pulsed Field Ablation (MANIFEST-PF) registry.

Design, Setting, and Participants

This was a retrospective cohort study of MANIFEST-PF registry data, which included consecutive patients undergoing postregulatory approval treatment with PFA to treat AF between March 2021 and May 2022 with a median follow-up of 1 year. MANIFEST-PF is a multinational, retrospectively analyzed, prospectively enrolled patient-level registry including 24 European centers. The study included all consecutive registry patients (age ≥18 years) who underwent first-ever PFA for paroxysmal or persistent AF.

Exposure

PFA was performed on patients with AF. All patients underwent pulmonary vein isolation and additional ablation, which was performed at the discretion of the operator.

Main Outcomes and Measures

The primary effectiveness outcome was freedom from clinically documented atrial arrhythmia for 30 seconds or longer after a 3-month blanking period. The primary safety outcome was the composite of acute (<7 days postprocedure) and chronic (>7 days) major adverse events (MAEs).

Results

Of 1568 patients (mean [SD] age, 64.5 [11.5] years; 1015 male [64.7%]) with AF who underwent PFA, female patients, as compared with male patients, were older (mean [SD] age, 68 [10] years vs 62 [12] years; P < .001), had more paroxysmal AF (70.2% [388 of 553] vs 62.4% [633 of 1015]; P = .002) but had fewer comorbidities such as coronary disease (9% [38 of 553] vs 15.9% [129 of 1015]; P < .001), heart failure (10.5% [58 of 553] vs 16.6% [168 of 1015]; P = .001), and sleep apnea (4.7% [18 of 553] vs 11.7% [84 of 1015]; P < .001). Pulmonary vein isolation was performed in 99.8% of female (552 of 553) and 98.9% of male (1004 of 1015; P = .90) patients. Additional ablation was performed in 22.4% of female (124 of 553) and 23.1% of male (235 of 1015; P = .79) patients. The 1-year Kaplan-Meier estimate for freedom from atrial arrhythmia was similar in male and female patients (79.0%; 95% CI, 76.3%-81.5% vs 76.3%; 95% CI, 72.5%-79.8%; P = .28). There was also no significant difference in acute major AEs between groups (male, 1.5% [16 of 1015] vs female, 2.5% [14 of 553]; P = .19).

Conclusion and Relevance

Results of this cohort study suggest that after PFA for AF, there were no significant sex differences in clinical effectiveness or safety events.

Adverse events associated with amplatzer left atrial appendage occlusion delivery system: A Food and Drug Administration MAUDE database study

BACKGROUND

Dual occlusive closure mechanism (disc and lobe type), Amulet device (Abbott; a second-generation device that has replaced Amplatzer Cardiac Plug) was approved by the Food and Drug Administration (FDA) in August 2021 for percutaneous left atrial appendage occlusion (LAAO). However, real-world safety data on the delivery system (Amplatzer Cardiac Plug and Amplatzer Amulet device) are lacking.

OBJECTIVE

We sought to assess the type of adverse events associated with the Amplatzer LAAO delivery system using the FDA Manufacturer and User Facility Device Experience (MAUDE) database.

METHODS

A MAUDE database search was conducted on March 31, 2023, for reports received between February 2013 and March 2023 to capture all adverse events.

RESULTS

A total of 59 adverse events were reported, of which 58 were sheath-related events, and one was a wire-related event. The most commonly encountered issue was air embolism (19%, 11 events), followed by sheath thrombosis (13.8%, eight events, two of which were also associated with device thrombosis), kinked sheath (10.3%, six events), and sheath deformation (8.6%, five events). Patient-related adverse events included pericardial effusion requiring pericardiocentesis (22.4%, 13 events), vascular complications (20.7%, 12 events), and device dislodgement (5.2%, three events).

CONCLUSION

LAAO-related adverse events are increasingly being reported using the Amplatzer LAAO delivery sheath. It is anticipated that improvements in device technology, the advent of steerable sheaths, and operator experience will minimize these complications.

Adverse events associated with AveirTM VR leadless pacemaker: A Food and Drug Administration MAUDE database study

BACKGROUND

Leadless pacemaker (LP) offers an innovative approach for treating bradyarrhythmia, thus avoiding pacemaker pocket and lead-related complications. The Food and Drug Administration (FDA) has recently approved the Aveir™ leadless pacing system (screw-in type LP).

METHODS

We queried the FDA MAUDE database to study the safety profile and assess the types of complications with this relatively novel device technology. A MAUDE database search was conducted on January 20, 2023, for reports received post-FDA approval to capture all adverse events.

RESULTS

A total of 98 medical device report were reported for Aveir™ LP. After excluding duplicate, programmer-related, or introducer-sheath-related entries (n = 34), 64 entries were included. The most commonly encountered problem was high threshold/noncapture (28.1%, 18 events), followed by stretched helix (17.2%, 11 events) and device dislodgement (15.6%, ten events-5 intraprocedural, while 5 in the postoperative Day 1). Other reported events included high impedance (14.1%, nine events), sensing issues (12.5%, eight events), bent/broken helix (7.8%, five events), premature separation (4.7%, three events), interrogation problem (3.1%, two events), low impedance (3.1%, two events), premature battery depletion (1.6%, one event) and inadvertent MRI mode switch (1.6%, one event) and miscellaneous (15.6%, n = 10). There were eight serious patient injury events-pericardial effusion requiring pericardiocentesis (7.8%, five events) due to cardiac perforation that resulted in two deaths (3.1%) followed by sustained ventricular arrhythmias (4.6%, n = 3).

CONCLUSION

In our study assessing the real-world safety profile of the Aveir™ LP, serious adverse events have been reported-life-threatening ventricular arrhythmias, pericardial effusion, device explantation/reimplantation, and death.

Safety and Effectiveness of Pulsed Field Ablation to Treat Atrial Fibrillation: One-Year Outcomes From the MANIFEST-PF Registry

BACKGROUND

Pulsed field ablation is a novel nonthermal cardiac ablation modality using ultra-rapid electrical pulses to cause cell death by a mechanism of irreversible electroporation. Unlike the traditional ablation energy sources, pulsed field ablation has demonstrated significant preferentiality to myocardial tissue ablation, and thus avoids certain thermally mediated complications. However, its safety and effectiveness remain unknown in usual clinical care.

METHODS

MANIFEST-PF (Multi-National Survey on the Methods, Efficacy, and Safety on the Post-Approval Clinical Use of Pulsed Field Ablation) is a retrospective, multinational, patient-level registry wherein patients at each center were prospectively included in their respective center registries. The registry included all patients undergoing postapproval treatment with a multielectrode 5-spline pulsed field ablation catheter to treat atrial fibrillation (AF) between March 1, 2021, and May 30, 2022. The primary effectiveness outcome was freedom from clinical documented atrial arrhythmia (AF/atrial flutter/atrial tachycardia) of ≥30 seconds on the basis of electrocardiographic data after a 3-month blanking period (on or off antiarrhythmic drugs). Safety outcomes included the composite of acute (<7 days postprocedure) and latent (>7 days) major adverse events.

RESULTS

At 24 European centers (77 operators) pulsed field ablation was performed in 1568 patients with AF: age 64.5±11.5 years, female 35%, paroxysmal/persistent AF 65%/32%, CHA₂DS₂-VASc 2.2±1.6, median left ventricular ejection fraction 60%, and left atrial diameter 42 mm. Pulmonary vein isolation was achieved in 99.2% of patients. After a median (interquartile range) follow-up of 367 (289-421) days, the 1-year Kaplan-Meier estimate for freedom from atrial arrhythmia was 78.1% (95% CI, 76.0%-80.0%); clinical effectiveness was more common in patients with paroxysmal AF versus persistent AF (81.6% versus 71.5%; P=0.001). Acute major adverse events occurred in 1.9% of patients.

CONCLUSIONS

In this large observational registry of the postapproval clinical use of pulsed field technology to treat AF, catheter ablation using pulsed field energy was clinically effective in 78% of patients with AF.

SGLT2 inhibitors reduce sudden cardiac death risk in heart failure: Meta-analysis of randomized clinical trials

INTRODUCTION

Multiple randomized controlled trials have demonstrated sodium-glucose cotransporter-2 inhibitors (SGLT2i) decrease the composite endpoint of cardiovascular death or heart failure hospitalizations in all heart failure patients. It is uncertain whether SGLT2i impacts the risk of sudden cardiac death in patients with heart failure.

METHODS

A comprehensive search was performed to identify relevant data published before August 28, 2022. Trials were included if: (1) all patients had clinical heart failure (2) SGLT2i and placebo were compared (3) all patients received conventional medical therapy and (4) reported outcomes of interest (sudden cardiac death [SCD], ventricular arrhythmias, atrial arrhythmias).

RESULTS

SCD was reported in seven of the eleven trials meeting selection criteria: 10 796 patients received SGLT2i and 10 796 received placebo. SGLT2i therapy was associated with a significant reduction in the risk of SCD (risk ratios [RR]: 0.68; 95% confidence intervals [CI]: 0.48-0.95; p = .03; I2  = 0%). Absent dedicated rhythm monitoring, there were no significant differences in the incidence of sustained ventricular arrhythmias not associated with SCD (RR: 1.03; 95% CI: 0.83-1.29; p = .77; I2  = 0%) or atrial arrhythmias (RR: 0.91; 95% CI: 0.77-1.09; p = .31; I2  = 29%) between patients receiving an SGLT2i versus placebo.

CONCLUSION

SGLT2i therapy is associated with a reduced risk of SCD in patients with heart failure receiving contemporary medical therapy. Prospective trials are needed to determine the long-term impact of SGLT2i therapy on atrial and ventricular arrhythmias.

Permanent pacing versus cardioneuroablation for cardioinhibitory vasovagal syncope

BACKGROUND

We compared the efficacy and safety of cardioneuroablation (CNA) vs. permanent pacing (PM) for recurrent cardioinhibitory vasovagal syncope (CI-VVS).

METHODS

One hundred sixty-two patients (CNA = 61, PM = 101), age 36 + 11 years) with syncope frequency of 6.7 ± 3.9/year were included in this multicenter study. All patients with CNA were provided by a single center, while patients with PM were provided by 4 other centers. In the CNA arm, an electroanatomic mapping guided approach was used to detect and ablate ganglionated plexus sites. Dual chamber rate drop response (RDR) or close loop stimulation (CLS) transvenous and leadless pacemakers were implanted using standard technique. The primary endpoint was freedom from syncope.

RESULTS

Of 101 patients in the PM group, 39 received dual-chamber pacemaker implants with the CLS algorithm, 38 received dual-chamber pacemakers with the RDR algorithm, and 24 received a leadless pacemaker. At 1-year follow-up, 97% and 89% in the CNA and PM group met the primary endpoint (adjusted HR = 0.27, 95% CI 0.06-1.24, p = 0.09). No significant differences in adverse events were noted between groups. There was no significant association between age (HR:1.01, 95% CI 0.96-1.06, p = 0.655), sex (HR:1.15, 95% CI 0.38-3.51, p = 0.809), and syncope frequency in the past year (HR:1.10, 95% CI 0.97-1.25, p = 0.122) and the primary outcome in univariable analyses.

CONCLUSIONS

After adjustment for patient characteristics, the medium-term syncope recurrence risk of CI-VVS patients who underwent CNA was similar to that of a population of patients undergoing pacemaker implantation with a similar safety profile.

Multi-national survey on the methods, efficacy, and safety on the post-approval clinical use of pulsed field ablation (MANIFEST-PF)

AIMS

Pulsed field ablation (PFA) is a novel atrial fibrillation (AF) ablation modality that has demonstrated preferential tissue ablation, including no oesophageal damage, in first-in-human clinical trials. In the MANIFEST-PF survey, we investigated the 'real world' performance of the only approved PFA catheter, including acute effectiveness and safety-in particular, rare oesophageal effects and other unforeseen PFA-related complications.

METHODS AND RESULTS

This retrospective survey included all 24 clinical centres using the pentaspline PFA catheter after regulatory approval. Institution-level data were obtained on patient characteristics, procedure parameters, acute efficacy, and adverse events. With an average of 73 patients treated per centre (range 7-291), full cohort included 1758 patients: mean age 61.6 years (range 19-92), female 34%, first-time ablation 94%, paroxysmal/persistent AF 58/35%. Most procedures employed deep sedation without intubation (82.1%), and 15.1% were discharged same day. Pulmonary vein isolation (PVI) was successful in 99.9% (range 98.9-100%). Procedure time was 65 min (38-215). There were no oesophageal complications or phrenic nerve injuries persisting past hospital discharge. Major complications (1.6%) were pericardial tamponade (0.97%) and stroke (0.4%); one stroke resulted in death (0.06%). Minor complications (3.9%) were primarily vascular (3.3%), but also included transient phrenic nerve paresis (0.46%), and TIA (0.11%). Rare complications included coronary artery spasm, haemoptysis, and dry cough persistent for 6 weeks (0.06% each).

CONCLUSION

In a large cohort of unselected patients, PFA was efficacious for PVI, and expressed a safety profile consistent with preferential tissue ablation. However, the frequency of 'generic' catheter complications (tamponade, stroke) underscores the need for improvement.

Conduction system pacing in prosthetic heart valves

BACKGROUND

There has been increasing interest in physiologic pacing techniques that directly activate the specialized conduction system. We aimed to assess outcomes of conduction system pacing (CSP) in patients with prosthetic heart valves.

METHODS

This systematic review was performed according to PRISMA guidelines. Freeman-Tukey double arcsine transformation with the random-effect model was used to summarize the data. Outcomes studied were 1) implant success (defined as ability to recruit the His-Purkinje system or the distal Purkinje system); (2) lead parameters at implant and follow-up; and (3) procedure-related complications.

RESULTS

This systematic review of 7 studies included 267 unique patients in whom CSP was attempted with either HBP or LBBAP for pacing indications after a prosthetic valve. HBP was attempted in 38% (n = 108), while LBBAP in 62% (n = 175) patients. The overall success rate of CSP was 87%, while in patients post-TAVR, the overall success rate was 83.2%. In the subgroup analysis, LBBAP had a significant higher overall success rate compared to HBP (94.3% vs. 76.5%, p _interaction = 0.02) and post-TAVR patients (94.3 vs. 66.9%, p _interaction < 0.01), respectively. The LBBAP thresholds were significantly lower compared to HBP both at implant (0.67 ± 0.4 @ 0.44 ms vs. 1.35 ± 1 @ 0.85 ms, p _interaction < 0.01) and at a mean follow-up of 12.4 ± 8 months (0.73 ± 0.1 @ 0.44 ms vs. 1.39 ± 1 @ 0.85 ms, p _interaction < 0.01), respectively.

CONCLUSION

CSP is safe and feasible in patients with a prosthetic valve, with a significantly higher success rate and superior lead parameters with LBBAP than HBP, especially in patients post-TAVR.

Surgical left atrial appendage occlusion in patients with left ventricular assist device

BACKGROUND

Thromboembolic (TE) events are among the most common and devastating adverse events in patients with continuous-flow left ventricular assist device (cf-LVAD). Given the high burden of AF among cf-LVAD patients, we sought to evaluate the effect of concomitant surgical LAAO in patients receiving cf-LVAD.

METHODS

A systematic search using electronic databases was performed using the keywords: "left atrial appendage occlusion" and "left ventricular assist device." Statistical analysis was performed using meta-package for R version 4.0 and Rstudio version 1.2. Mantel-Haenszel risk ratio (RR) random-effects model was used to summarize data between two groups. The primary outcomes included: (a) stroke; (b) LVAD pump thrombosis; (c) all-cause mortality RESULTS: : Three studies with a total of 305 patients (LAAO=68 and No-LAAO=237) were included in the analysis. HeartMate II (39%) and Heartware (27.5%) were the two most common cf-LVADs utilized, while only 5% received HeartMate III. At a mean follow up of 1.47 years, LAAO group had a lower risk of stroke (8.8% vs 15.2%, RR 0.64; 95% CI 0.28 - 1.49), LVAD pump thrombosis (1.5% vs 3.8%, RR 0.28; 95% CI 0.05 - 1.55) and all-cause mortality (5.9% vs 20.2%, RR 0.69; 95% CI 0.19 - 2.52) when compared with no-LAAO group, but the difference did not reach statistical significance.

CONCLUSION

Concomitant surgical LAAO at the time of cf-LVAD implantation demonstrated a trend towards positive outcomes and was not associated with adverse outcomes during the follow-up period, though the results were not statistically significant This article is protected by copyright. All rights reserved.

Intracardiac Echocardiography-Guided Left Atrial Appendage Closure With a Novel Foam-Based Conformable Device: Safety and 1-Year Outcomes

OBJECTIVES

This is a first report of the safety and 1-year outcomes of left atrial appendage closure (LAAC) using a novel foam-based conformable device, guided by intracardiac echocardiography (ICE).

BACKGROUND

Limitations of current transcatheter LAAC devices include the need for precise coaxial delivery into the left atrial appendage (LAA), potential for traumatic implantation, incomplete LAA seal, and device-related thrombus.

METHODS

The device (Conformal Left Atrial Appendage Seal, Conformal Medical Inc) is a self-expanding occluder consisting of a cylindrical nitinol endoskeleton with low-profile anchor barbs around the midpoint, covered with a porous foam cup. In a prospective single-center series, under conscious sedation, the device was delivered under fluoroscopic and ICE guidance. After positioning, a transesophageal echocardiography probe was placed to confirm ICE findings before device release. After closure, dual antiplatelet therapy was administered for 6 months. Follow-up imaging was planned for 45 days and 6 and 12 months.

RESULTS

A total of 15 patients (age 71.3 ± 10.8 years, 33% men, CHA₂DS₂-VASc 4.1 ± 1.7, HAS-BLED 3.4 ± 1.4) underwent LAAC, 100% successfully. There were no procedure/device-related complications requiring intervention. Asymptomatic pericardial effusion occurred in 2 patients. The 45-day, 6-month, and 12-month follow-up imaging in 11, 9, and 13 patients, respectively, revealed adequate LAA seal (leak ≤5 mm) in all patients; device-related thrombus was detected in 1 patient at 6 months. Over 1-year follow-up, there were no ischemic strokes and 1 minor bleed. Nonprocedure-/device-related death occurred in 2 patients.

CONCLUSIONS

This first report indicates that LAAC with the conformable implant guided by ICE imaging is feasible with encouraging 1-year clinical outcomes. (The Conformal Prague Study; NCT04193826).

Cardiac Resynchronization Therapy in continuous flow Left Ventricular Assist Device Recipients: A Systematic Review and Meta-analysis from ELECTRAM Investigators

Introduction

Whether cardiac resynchronization therapy (CRT) continues to augment left ventricular remodeling in patients with the continuous-flow left ventricular assist device (cf-LVAD) remains unclear.

Methods

We performed a systematic review and meta-analysis of all clinical studies examining the role of continued CRT in end-stage heart failure patients with cf-LVAD reporting all-cause mortality, ventricular arrhythmias, and ICD shocks. Mantel-Haenszel risk ratio (RR) random-effects model was used to summarize data.

Results

Eight studies (7 retrospective and 1 randomized) with a total of 1,208 unique patients met inclusion criteria. There was no difference in all-cause mortality (RR 1.08, 95% CI 0.86 - 1.35, p = 0.51, I2=0%), all-cause hospitalization (RR 1.01, 95% CI 0.76-1.34, p = 0.95, I²=11%), ventricular arrhythmias (RR 1.08, 95% CI 0.83 - 1.39, p = 0.58, I² =50%) and ICD shocks (RR 0.87, 95% CI 0.57 - 1.33, p = 0.52, I² =65%) comparing CRT versus non-CRT. Subgroup analysis demonstrated significant reduction in ventricular arrhythmias (RR 0.76, 95% CI 0.64 - 0.90, p = 0.001) and ICD shocks (RR 0.65, 95% CI 0.44 - 0.97, p = 0.04) in "CRT on" group versus "CRT off" group.

Conclusions

CRT was not associated with a reduction in all-cause mortality or increased risk of ventricular arrhythmias and ICD shocks compared to non-CRT in cf-LVAD patients. It remains to be determined which subgroup of cf-LVAD patients benefit from CRT. The findings of our study are intriguing, and therefore, larger studies in a randomized prospective manner should be undertaken to address this specifically.

Active Implantable cardioverter-defibrillators in Continuous-flow Left Ventricular Assist Device Recipients

Introduction

Implantable cardioverter-defibrillator (ICD) in patients with heart failure with reduced ejection fraction reduces mortality secondary to malignant arrhythmias. Whether end-stage heart failure (HF) with continuous-flow left ventricular assist device (cf-LVAD) derive similar benefits remains controversial.

Methods

We performed a systematic literature review and meta-analysis of all published studies that examined the association between active ICDs and survival in advanced HF patients with cfLVAD. We searched PubMed, Medline, Embase, Ovid, and Cochrane for studies reporting the association between ICD and all-cause mortality in advanced HF patients with cfLVAD. Mantel-Haenszel risk ratio (RR) random-effects model was used to summarize data.

Results

Ten studies (9 retrospective and one prospective) with a total of 7,091 patients met inclusion criteria. There was no difference in all-cause mortality (RR 0.84, 95% CI 0.65-1.10, p=0.20, I² =62.40%), likelihood of survival to transplant (RR 1.07, 95% CI 0.98-1.17, p= 0.13, I² =0%), RV failure (RR 0.74, 95% CI 0.44-1.25, p = 0.26, I² =34%) between Active ICD and inactive/no ICD groups, respectively. Additionally, 27.5% received appropriate ICD shocks, while 9.5% received inappropriate ICD shocks. No significant difference was observed in terms of any complications between the two groups.

Conclusions

All-cause mortality, the likelihood of survival to transplant, and worsening RV failure were not significantly different between active ICD and inactive/no ICD in cf-LVAD recipients. A substantial number of patients received appropriate ICD shocks suggesting a high-arrhythmia burden. The risks and benefits of ICDs must be carefully considered in patients with cf-LVAD.

Left Atrial Appendage Occlusion Device Embolization (The LAAODE Study): Understanding the Timing and Clinical Consequences from a Worldwide Experience

Background

Left atrial appendage occlusion device embolization (LAAODE) is rare but can have substantial implications on patient morbidity and mortality. Hence, we sought to perform an analysis to understand the timing and clinical consequences of LAAODE.

Methods

A comprehensive search of PubMed and Web of Science databases for LAAODE cases was performed from October 2nd, 2014 to November 1st, 2017. Prior to that, we included published LAAODE cases until October 1st, 2014 reported in the systematic review by Aminian et al.

Results

103 LAAODE cases including Amplatzer cardiac plug (N=59), Watchman (N=31), Amulet (N=11), LAmbre (N=1) and Watchman FLX (N=1) were included. The estimated incidence of device embolization was 2% (103/5,000). LAAODE occurred more commonly in the postoperative period compared with intraoperative (61% vs. 39%). The most common location for embolization was the descending aorta 30% (31/103) and left atrium 24% (25/103) followed by left ventricle 20% (21/103). Majority of cases 75% (77/103) were retrieved percutaneously. Surgical retrieval occurred most commonly for devices embolized to the left ventricle, mitral apparatus and descending aorta. Major complications were significantly higher with postoperative LAAODE compared with intraoperative (44.4% vs. 22.5%, p=0.03).

Conclusions

LAAODE is common with a reported incidence of 2% in our study. Post-operative device embolization occurred more frequently and was associated with a higher rate of complications than intraoperative device embolizations. Understanding the timings and clinical sequelae of DE can aid physicians with post procedural follow-up and also in the selection of patients for these procedures.

A single-center experience with early adoption of physiologic pacing approaches

BACKGROUND

Increasing interest in physiological pacing has been countered with challenges such as accurate lead deployment and increasing pacing thresholds with His-bundle pacing (HBP). More recently, left bundle branch area pacing (LBBAP) has emerged as an alternative approach to physiologic pacing.

OBJECTIVE

To compare procedural outcomes and pacing parameters at follow-up during initial adoption of HBP and LBBAP at a single center.

METHODS

Retrospective review, from September 2016 to January 2020, identified the first 50 patients each who underwent successful HBP or LBBAP. Pacing parameters were then assessed at first follow-up after implantation and after approximately 1 year, evaluating for acceptable pacing parameters defined as sensing R-wave amplitude >5 mV, threshold <2.5 V @ 0.5 ms, and impedance between 400 and 1200 Ω.

RESULTS

The HBP group was younger with lower ejection fraction compared to LBBAP (73.2 ± 15.3 vs. 78.2 ± 9.2 years, p = .047; 51.0 ± 15.9% vs. 57.0 ± 13.1%, p = .044). Post-procedural QRS widths were similarly narrow (119.8 ± 21.2 vs. 116.7 ± 15.2 ms; p = .443) in both groups. Significantly fewer patients with HBP met the outcome for acceptable pacing parameters at initial follow-up (56.0% vs. 96.4%, p = .001) and most recent follow-up (60.7% vs. 94.9%, p ≤ .001; at 399 ± 259 vs. 228 ± 124 days, p ≤ .001). More HBP patients required lead revision due to early battery depletion or concern for pacing failure (0% vs. 13.3%, at a mean of 664 days).

CONCLUSION

During initial adoption, HBP is associated with a significantly higher frequency of unacceptable pacing parameters, energy consumption, and lead revisions compared with LBBAP.

Implantable cardioverter-defibrillator in patients with spontaneous coronary artery dissection presenting with sudden cardiac arrest

INTRODUCTION

The role of secondary prevention implantable cardioverter-defibrillator (ICD) remains uncertain in spontaneous coronary artery dissection (SCAD) patients presenting with sudden cardiac arrest (SCA).

METHODS

We aimed at assessing the outcomes following SCA and the role of ICD therapy in SCAD. The meta-analysis was performed using a meta-package for R version 4.0/RStudio version 1.2 and the Freeman-Tukey double arcsine method to establish the variance of raw proportions. Outcomes measured included-(1) incidence of ICD implantation, (2) appropriate and inappropriate ICD therapy, (3) recurrence of SCAD and SCA, and (4) all-cause mortality.

RESULTS

Five studies, including 139 SCAD patients with SCA met study inclusion criteria. The mean age was 47.3 ± 12.8 years, mean left ventricular ejection fraction 43.8 ± 10.8%, 88% were female (12% had pregnancy-associated SCAD. Causes of SCA included ventricular arrhythmia (97.9%, n = 136) and pulseless electrical activity (2.1%, n = 3). Overall, 20% patients (95% confidence interval [CI]: 7.1%-36.6%, I² = 68%) received ICD, of which 1.2% (95% CI: 0%-15.8%, I² = 0%) and 1% (95% CI: 0%-15.3%, I² = 0%) patients received appropriate and inappropriate ICD therapies, respectively, during follow-up period (4.1 ± 3.3 years). Incidence of recurrent SCAD was 9% (95% CI: 2.85%-17.5%, I² = 25%), and recurrent SCA was 3.85% patients (95% CI: 0.65%-8.7%, I² = 0%; one patient with appropriate ICD therapy). The pooled incidence of all-cause mortality was 6.2% (95% CI: 0.6%-15.1%, I² = 44%).

CONCLUSION

Although ICD therapy is beneficial in patients (all comers) presenting with cardiac arrest; the risk-benefit ratio of secondary prevention ICD arrest remains unclear. Patient-centered shared decision-making and risk-benefit ratio assessment should be performed before consideration for ICD implantation.