Feasibility of Amulet occluder implantation after failed left atrial appendage occlusion attempt: Insights from the EMERGE LAA postapproval study.

BACKGROUND: Although expertise in left atrial appendage occlusion (LAAO) has grown, certain intricate anatomies may pose challenges, rendering them unsuitable for LAAO with the selected device. OBJECTIVE: This analysis aimed to characterize outcomes of patients with prior failed percutaneous LAAO procedures who underwent a subsequent attempt with an Amulet occluder in the EMERGE LAA postapproval study. METHODS: Patients enrolled in the National Cardiovascular Data Registry LAAO Registry who had an Amulet occluder implantation attempt between Food and Drug Administration approval (August 14, 2021) and June 30, 2023, were evaluated. A safety end point through 7 days or hospital discharge (whichever was later) and major adverse events through 45 days were reported. RESULTS: A total of 8591 patients underwent attempted Amulet occluder implantation, of whom 244 patients had prior failed LAAO. Implantation success was 88.9% and 96.2% in patients with prior failed LAAO and index LAAO, respectively (P < .001). The safety composite end point was low, occurring in 1.6% and 0.8% of patients with prior failed LAAO and index LAAO, respectively (P = .148). Any major adverse event through 45 days occurred in 7.4% and 6.3% of prior failed LAAO and index LAAO patient cohorts, respectively (P = .497); most adverse events were similar between the groups (P > .05). At 45 days, peridevice leak ≤3 mm was achieved in >90% of patients in either group. CONCLUSION: A high degree of implantation success with a low rate of adverse events can be achieved with the Amulet occluder. The findings imply that the dual occlusive mechanism Amulet occluder facilitates successful closure, even in challenging anatomic scenarios.

First Experience With Amulet in the United States: Early Insights From EMERGE LAA Postapproval Study.

BACKGROUND: The Food and Drug Administration approved the Amulet occluder (Abbott) after demonstrating safety and effectiveness in the Amulet IDE (AMPLATZER Amulet LAA Occluder) trial. OBJECTIVES: The aim of the EMERGE Left Atrial Appendage study is to evaluate early postapproval outcomes of the Amulet occluder in the United States using data from the National Cardiovascular Data Registry Left Atrial Appendage Occlusion Registry. METHODS: Patients with a commercial Amulet occluder implant attempt between Food and Drug Administration approval (August 14, 2021) and December 31, 2022, were included. The safety composite endpoint included all-cause death, ischemic stroke, systemic embolism, or device/procedure-related events requiring open cardiac surgery or endovascular intervention between device implantation and 7 days or hospital discharge (whichever is later). Major adverse events through 45 days were also reported and stratified by operator experience (early [<10 cases], moderate [10-29 cases], and high [30+ cases]). RESULTS: A total of 5,499 patients underwent attempted Amulet occluder implantation. Implant success was 95.8%, and complete closure was 97.2% post-left atrial appendage occlusion and 87.1% at 45 days. A safety composite endpoint event occurred in 0.76% patients. Any major adverse event occurred in 2.9% and 5.7% of patients in-hospital and through 45 days, respectively, driven by major bleeding and pericardial effusion (PE) requiring intervention. PE requiring surgery or percutaneous intervention decreased significantly with increasing experience both in-hospital (early vs high operator experience 1.8% vs 1.1%; P = 0.006) and at 45 days (2.3% vs 1.5%; P = 0.012). CONCLUSIONS: The EMERGE Left Atrial Appendage study demonstrates favorable safety and effectiveness of the Amulet occluder in the real-world setting. More experienced operators had improved implant success and fewer PEs, suggesting a learning curve effect implanting this dual occlusive mechanism device.

Determinants of outcome impact of vein of Marshall ethanol infusion when added to catheter ablation of persistent atrial fibrillation: A secondary analysis of the VENUS randomized clinical trial.

BACKGROUND: The Vein of Marshall Ethanol for Untreated Persistent AF (VENUS) trial demonstrated that adding vein of Marshall (VOM) ethanol infusion to catheter ablation (CA) improves ablation outcomes in persistent atrial fibrillation (AF). There was significant heterogeneity in the impact of VOM ethanol infusion on rhythm control. OBJECTIVE: The purpose of this study was to assess the association between outcomes and (1) achievement of bidirectional perimitral conduction block and (2) procedural volume. METHODS: The VENUS trial randomized patients with persistent AF (N = 343) to CA combined with VOM ethanol or CA alone. The primary outcome (freedom from AF or atrial tachycardia [AT] lasting longer than 30 seconds after a single procedure) was analyzed by 2 categories: (1) successful vs no perimitral block and (2) high- (>20 patients enrolled) vs low-volume centers. RESULTS: In patients with perimitral block, the primary outcome was reached 54.3% after VOM-CA and 37% after CA alone (P = .01). Among patients without perimitral block, freedom from AF/AT was 34.0% after VOM-CA and 37.0% after CA (P = .583). In high-volume centers, the primary outcome was reached in 56.4% after VOM-CA and 40.2% after CA (P = .01). In low-volume centers, freedom from AF/AT was 30.77% after VOM-CA and 32.61% after CA (P = .84). In patients with successful perimitral block from high-volume centers, the primary outcome was reached in 59% after VOM-CA and 39.1% after CA (P = .01). Tests for interaction were significant (P = .002 for perimitral block and P = .04 for center volume). CONCLUSION: Adding VOM ethanol infusion to CA has a greater impact on outcomes when associated with perimitral block and performed in high-volume centers. Perimitral block should be part of the VOM procedure.

Effect of Catheter Ablation With Vein of Marshall Ethanol Infusion vs Catheter Ablation Alone on Persistent Atrial Fibrillation: The VENUS Randomized Clinical Trial.

Importance: Catheter ablation of persistent atrial fibrillation (AF) has limited success. Procedural strategies beyond pulmonary vein isolation have failed to consistently improve results. The vein of Marshall contains innervation and AF triggers that can be ablated by retrograde ethanol infusion. Objective: To determine whether vein of Marshall ethanol infusion could improve ablation results in persistent AF when added to catheter ablation. Design, Setting, and Participants: The Vein of Marshall Ethanol for Untreated Persistent AF (VENUS) trial was an investigator-initiated, National Institutes of Health-funded, randomized, single-blinded trial conducted in 12 centers in the United States. Patients (N = 350) with persistent AF referred for first ablation were enrolled from October 2013 through June 2018. Follow-up concluded in June 2019. Interventions: Patients were randomly assigned to catheter ablation alone (n = 158) or catheter ablation combined with vein of Marshall ethanol infusion (n = 185) in a 1:1.15 ratio to accommodate for 15% technical vein of Marshall ethanol infusion failures. Main Outcomes and Measures: The primary outcome was freedom from AF or atrial tachycardia for longer than 30 seconds after a single procedure, without antiarrhythmic drugs, at both 6 and 12 months. Outcome assessment was blinded to randomization treatment. There were 12 secondary outcomes, including AF burden, freedom from AF after multiple procedures, perimitral block, and others. Results: Of the 343 randomized patients (mean [SD] age, 66.5 [9.7] years; 261 men), 316 (92.1%) completed the trial. Vein of Marshall ethanol was successfully delivered in 155 of 185 patients. At 6 and 12 months, the proportion of patients with freedom from AF/atrial tachycardia after a single procedure was 49.2% (91/185) in the catheter ablation combined with vein of Marshall ethanol infusion group compared with 38% (60/158) in the catheter ablation alone group (difference, 11.2% [95% CI, 0.8%-21.7%]; P = .04). Of the 12 secondary outcomes, 9 were not significantly different, but AF burden (zero burden in 78.3% vs 67.9%; difference, 10.4% [95% CI, 2.9%-17.9%]; P = .01), freedom from AF after multiple procedures (65.2% vs 53.8%; difference, 11.4% [95% CI, 0.6%-22.2%]; P = .04), and success achieving perimitral block (80.6% vs 51.3%; difference, 29.3% [95% CI, 19.3%-39.3%]; P < .001) were significantly improved in vein of Marshall-treated patients. Adverse events were similar between groups. Conclusions and Relevance: Among patients with persistent AF, addition of vein of Marshall ethanol infusion to catheter ablation, compared with catheter ablation alone, increased the likelihood of remaining free of AF or atrial tachycardia at 6 and 12 months. Further research is needed to assess longer-term efficacy. Trial Registration: ClinicalTrials.gov Identifier: NCT01898221.

Use of a pocket compression device for the prevention and treatment of pocket hematoma after pacemaker and defibrillator implantation (STOP-HEMATOMA-I).

BACKGROUND: Pocket hematoma is a recognized complication after placement of cardiac implantable electronic devices and is associated with increased device infection, length of hospitalization, and morbidity especially with uninterrupted antiplatelet agents and anticoagulants. We assessed the use of a post-surgical vest to decrease the incidence of pocket hematoma in patients undergoing device implantation with uninterrupted antiplatelet and anticoagulants. METHODS: In this observational study, a vest was used by 20 consecutive patients who were compared to 20 age-, gender-, procedure-matched patients who received standard care. All patients were continued on antiplatelet and anticoagulants in the perioperative period. The pocket was assessed at post procedure day 0, 2, and 7, respectively. RESULTS: There were no significant differences in the baseline characteristics between both groups. Baseline mean international normalized ratio (INR) was significantly higher in the vest group when compared with the control group (2.7 ± 0.4 vs. 2.2 ± 0.3 = <0.001). The incidence of pocket hematoma was significantly lower in the vest group than the control group (0 vs 30%, p = 0.02) at the end of 7 days. Control group had a total of six hematomas with one patient requiring evacuation and blood transfusion. The vest group had three hematomas on day 2 that resolved by day 7. CONCLUSIONS: The risk of moderate or large pocket hematoma is significantly reduced with the use of this vest in high-risk patients undergoing implantable devices on uninterrupted antiplatelet and anticoagulants.

Dosimetric review of cardiac implantable electronic device patients receiving radiotherapy.

A formal communication process was established and evaluated for the management of patients with cardiac implantable electronic devices (CIEDs) receiving radiation therapy (RT). Methods to estimate dose to the CIED were evaluated for their appropriateness in the management of these patients. A retrospective, institutional review board (IRB) approved study of 69 patients with CIEDs treated with RT between 2005 and 2011 was performed. The treatment sites, techniques, and the estimated doses to the CIEDs were analyzed and compared to estimates from published peripheral dose (PD) data and three treatment planning systems(TPSs) - UMPlan, Eclipse's AAA and Acuros algorithms. When measurements were indicated, radiation doses to the CIEDs ranged from 0.01-5.06 Gy. Total peripheral dose estimates based on publications differed from TLD measurements by an average of 0.94 Gy (0.05-4.49 Gy) and 0.51 Gy (0-2.74 Gy) for CIEDs within 2.5 cm and between 2.5 and 10 cm of the treatment field edge, respectively. Total peripheral dose estimates based on three TPSs differed from measurements by an average of 0.69 Gy (0.02-3.72 Gy) for CIEDs within 2.5 cm of the field edge. Of the 69 patients evaluated in this study, only two with defibrillators experienced a partial reset of their device during treatment. Based on this study, few CIED-related events were observed during RT. The only noted correlation with treatment parameters for these two events was beam energy, as both patients were treated with high-energy photon beams (16 MV). Differences in estimated and measured CIED doses were observed when using published PD data and TPS calculations. As such, we continue to follow conservative guidelines and measure CIED doses when the device is within 10 cm of the field or the estimated dose is greater than 2 Gy for pacemakers or 1 Gy for defibrillators.

Empirical amphotericin B therapy on day 4 or day 8 of febrile neutropenia.

Febrile neutropenic patients are at greater risk of getting bacterial and fungal infections. Empirical antifungal therapy is considered if the fever persists despite broad-spectrum antibiotics including vancomycin. However, the timing of initiating empirical antifungal therapy can vary from 3 to 8 days of non-response to antibiotics. We choose to determine the response of empirical amphotericin B deoxycholate (dAMB) starting either on day 4 or day 8 in febrile neutropenic patients not responding to broad-spectrum antibiotics and without localisation of fever. Fifty-six patients with persistent neutropenic fever despite 72 h of antibiotic therapy were randomly assigned to receive dAMB either starting on day 4 (group A, n = 27, median age 23 years) or starting on day 8 (group B, n = 29, median age 25 years). Satisfactory response (patient remaining afebrile for 48 h and maintaining absolute neutrophil count >500 µl(-1) ) occurred in 85.2% of patients in group A vs. 69.5% in group B (P = 0.209). Patients in group A took significantly fewer days to become afebrile than group B (5.4 ± 3.9 days vs. 11.3 ± 4.0 days, P = 0.0001). The adverse side effects of dAMB (nephrotoxicity, hypokalemia and hypomagnesemia) occurred at similar rates in both groups. Early addition of empirical dAMB in febrile neutropenic patients leads to their early defervescence and decreased dose requirement.

Manifestations of coronary arterial injury during catheter ablation of atrial fibrillation and related arrhythmias.

BACKGROUND: The prevalence and clinical consequences of coronary arterial injury in a large series of patients undergoing radiofrequency ablation (RFA) of atrial fibrillation (AF) are unknown. OBJECTIVE: The purpose of this study was to describe the frequency and clinical consequences of coronary arterial injury in a large series of patients undergoing catheter ablation of AF and postablation atrial tachycardia. METHODS: The medical records of 5,709 consecutive patients undergoing RFA of AF were reviewed. Heart specimens were also dissected to analyze the course of the coronary arteries. RESULTS: Arterial injury occurred in 8 patients (0.14%). Three patients developed ventricular fibrillation (VF) due to occlusion of the distal or proximal circumflex (Cx) artery related to RFA in the distal coronary sinus (CS) or base of the LA appendage, respectively. Two VF patients underwent stenting. Five patients developed acute sinus node (SN) dysfunction. In 4/5 patients, the culprit site was subjacent to the SN artery (per computed tomography) coursing over the anterior LA (n = 3) or the septal RA (n = 1). Two patients required a permanent pacemaker. In the heart specimens, the SN artery, after its origin from the proximal Cx artery, coursed along the anterior LA. Also, the proximal Cx artery was found in the atrioventricular groove underneath the base of the LA appendage. CONCLUSION: Clinically apparent injury to the coronary arteries during LA ablation for AF is rare. However, it may be associated with potentially life-threatening ventricular arrhythmias and acute SN dysfunction requiring permanent pacing. The culprit sites seem to be in the distal coronary sinus and the anterior LA, and correlate well with the course of the coronary arteries in pathologic specimens. Vigilance and low-power settings are important in minimizing the risk of arterial injury.

Stellate ganglion block: a therapeutic alternative for patients with medically refractory inappropriate sinus tachycardia?

Inappropriate sinus tachycardia (IST) is a clinical syndrome characterized by presence of non-paroxysmal tachyarrhythmia manifesting with increased resting heart rate and exaggerated or persistent response to exercise or position. When IST is intolerable and medically refractory, invasive therapies such as sinus node modification or atrioventricular node ablation with placement of permanent pacemaker are tried to control symptoms. We present a 34 year old patient with symptomatic IST unresponsive to medical therapy who underwent anesthetic block of the right and left stellate ganglia. At four month follow up the patient demonstrated sustained improvement in heart rate and reported freedom from previous symptoms.

Characteristics of atrial tachycardia due to small vs large reentrant circuits after ablation of persistent atrial fibrillation.

BACKGROUND: While macroreentrant atrial tachycardias (ATs) have been reasonably well described, little is known about small reentrant circuits. OBJECTIVE: To compare characteristics of large and small reentrant circuits after ablation of persistent atrial fibrillation. METHODS: Seventy-seven patients (age 61±10 years; left atrium 46±6 mm; ejection fraction 0.52±0.13) underwent a procedure for postablation AT. The p-wave duration, circuit size, electrogram characteristics, and conduction velocity were determined. RESULTS: AT was due to macroreentry in 62 (80%) patients, a small reentrant circuit in 13 (17%), and a focal mechanism in 2 (3%). The p-wave duration during small reentrant ATs was shorter than that during macroreentry (174±12 ms vs 226±22 ms; P<.0001). The duration of fractionated electrograms at the critical site was longer in small vs large circuits (167±43 ms vs 98±38 ms, respectively; P<.0001) and accounted for a greater percentage of the tachycardia cycle length (59%±18% vs 38%±14%, respectively; P<.0001). The mean diameters of macroreentrant and small reentrant circuits were 44±7 and 26±11 mm, respectively (P<.0001). The mean conduction velocity along the small circuits was lower (0.5±0.2 m/s vs 1.2±0.3 m/s; P<.0001). Catheter ablation eliminated the AT in all 77 patients. CONCLUSIONS: AT due to a small reentrant circuit after ablation of atrial fibrillation may be distinguished from macroreentry by a shorter p-wave duration and the presence of long-duration electrograms at the critical site owing to extremely slow conduction. These features may aid the clinician in the mapping of postablation ATs.

Effect of radiation therapy on permanent pacemaker and implantable cardioverter-defibrillator function.

BACKGROUND: Radiation therapy's (RT's) effects on cardiac implantable electronic devices (CIEDs) such as implantable cardioverter-defibrillators (ICDs) and pacemakers (PMs) are not well established, leading to device removal or relocation in preparation for RT. OBJECTIVE: To determine the effect of scattered RT on CIED performance. METHODS: We analyzed 69 patients--50 (72%) with PMs and 19 (28%) with ICDs--receiving RT at the University of Michigan. Collected data included device model, anatomic location, and treatment beam energies, treatment type, and estimated dose to the device. Patients were treated with either high-energy (16-MV) and/or low-energy (6 MV) photon beams with or without electron beams (6-16 MeV). The devices were interrogated with pre- and post-RT and/or weekly with either in-treatment or home interrogation, depending on the patient's dependence on the device and the estimated or measured delivered dose. Outcomes analyzed were inappropriate ICD therapies, device malfunctions, or device-related clinical events. RESULTS: The PMs were exposed to 84.4 ± 99.7 cGy of radiation, and the ICDs were exposed to 92.1 ± 72.6 cGy of radiation. Two patients with ICDs experienced a partial reset of the ICD with the loss of historic diagnostic data after receiving 123 and 4 cGy, respectively. No device malfunction or premature battery depletion was observed at 6-month follow-up from RT completion. CONCLUSIONS: CIED malfunction due to indirect RT exposure is uncommon. Regular in-treatment or home interrogation should be done to detect and treat these events and to ensure that diagnostic data are preserved.

Impact of valvular calcification on the diagnostic accuracy of transesophageal echocardiography for the detection of congenital aortic valve malformation.

BACKGROUND: Degeneration of congenital bicuspid or unicuspid aortic valves can progress more rapidly than that of tricuspid valves, and an early diagnosis significantly impacts decision making and outcome. We hypothesized that the extent of valvular calcification would negatively influence the diagnostic accuracy of multiplane transesophageal echocardiography (TEE) for the diagnosis of congenital aortic valve disease. METHODS: TEE was performed in 57 patients undergoing aortic valve replacement surgery for aortic stenosis (n = 46), pure regurgitation (n = 9), or significant regurgitation with less than severe aortic stenosis (n = 2). The degree of aortic valve calcification and the number of valve cusps were determined at surgery. RESULTS: Surgical inspection confirmed 14 bicuspid and 43 tricuspid aortic valves. Sensitivity and specificity of TEE for the diagnosis of congenital aortic valve malformation was 93% (13/14) and 91% (39/43) (P = 0.0001), respectively. In patients with no or mild aortic valve calcification (n = 13), sensitivity and specificity of TEE for the diagnosis of congenitally malformed aortic valve was 100% (5/5) and 100% (8/8) (P = 0.001), respectively. In patients with moderate or marked aortic valve calcification (n = 44), sensitivity and specificity of TEE for the diagnosis of congenitally malformed aortic valve was 89% (8/9) and 89% (31/35) (P<0.0001), respectively. In this subgroup of 44 patients, there were four false-positive and one false-negative diagnoses due to valvular calcification. CONCLUSIONS: Although TEE is highly sensitive and specific for the detection of congenital aortic valve malformations, presence of moderate or marked calcification of the aortic valve may result in false positive and false negative diagnoses.