Better Late Than Never: Definitive Anatomic Repair of Dextro-Transposition of the Great Arteries.

We present a case of anatomic repair of dextro-transposition of the great arteries (d-TGA) with ventricular septal defect (VSD) in a 55-year-old man who presented with acute heart failure. This case highlights the importance of multimodal imaging and multidisciplinary involvement in developing a comprehensive surgical and medical plan for adults with congenital heart disease. We think this is the oldest reported patient undergoing anatomic surgical repair of d-TGA with VSD.

Transient 2:1 Atrioventricular Block with Peri-Conduction System Pacing After Leadless Pacemaker Implantation.

This report discusses a case of transient 2:1 atrioventricular block with conduction system pacing 4 hours after leadless right ventricular pacemaker implantation in a 19-year-old patient with a history of cardioinhibitory syncope and asystole cardiac arrest but without preexisting atrioventricular block. The atrioventricular block was resolved spontaneously. Pacing morphology was suggestive of right bundle branch pacing. Neither 2:1 atrioventricular block nor conduction system pacing has previously been a reported outcome of right ventricular leadless pacemaker implantation. The report demonstrates that conduction system pacing with leadless devices is achievable. Further study of techniques, limitations, and complications related to intentional right ventricular leadless conduction system pacing is warranted.

Dronedarone for the Treatment of Atrial Arrhythmias in Adults With Congenital Heart Disease.

BACKGROUND: Atrial tachyarrhythmias are common and difficult to treat in adults with congenital heart disease. Dronedarone has proven effective in patients without congenital heart disease, but data are limited about its use in adults with congenital heart disease of moderate to great complexity. METHODS: A single-center, retrospective chart review of 21 adults with congenital heart disease of moderate to great complexity who were treated with dronedarone for atrial tachyarrhythmias was performed. RESULTS: The median (IQR) age at dronedarone initiation was 35 (27.5-39) years. Eleven patients (52%) were male. Ten patients (48%) had New York Heart Association class I disease, 10 (48%) had class II disease, and 1 (5%) had class III disease. Ejection fraction at initiation was greater than 55% in 11 patients (52%), 35% to 55% in 9 patients (43%), and less than 35% in 1 patient (5%). Prior treatments included ß-blockers (71%), sotalol (38%), amiodarone (24%), digoxin (24%), and catheter ablation (38%). Rhythm control was complete in 5 patients (24%), partial in 6 (29%), and inadequate in 10 (48%). Two patients (10%) experienced adverse events, including nausea in 1 (5%) and cardiac arrest in 1 (5%), which occurred 48 months after initiation of treatment. There were no deaths during the follow-up period. The median (IQR) follow-up time for patients with complete or partial rhythm control was 20 (1-54) months. CONCLUSION: Dronedarone can be effective for adult patients with congenital heart disease and atrial arrhythmias for whom more established therapies have failed, and with close monitoring it can be safely tolerated.

A Multisite Retrospective Review of Direct Oral Anticoagulants Compared to Warfarin in Adult Fontan Patients.

PURPOSE: Direct oral anticoagulants (DOACs) are not recommended in adult Fontan patients (Level of Evidence C). We hypothesized that DOACs are comparable to warfarin and do not increase thrombotic and embolic complications (TEs) or clinically significant bleeds. METHODS: We reviewed the medical records of adult Fontan patients on DOACs or warfarin at three major medical centers. We identified 130 patients: 48 on DOACs and 107 on warfarin. In total, they were treated for 810 months on DOACs and 5637 months on warfarin. RESULTS: The incidence of TEs in patients on DOACs compared to those on warfarin was not increased in a statistically significant way (hazard ratio [HR] 1.7 and p value 0.431). Similarly, the incidence of nonmajor and major bleeds in patients on DOACs compared to those on warfarin was also not increased in a statistically significant way (HR for nonmajor bleeds in DOAC patients was 2.8 with a p value of 0.167 and the HR for major bleeds was 2.0 with a p value 0.267). In multivariate analysis, congestive heart failure (CHF) was a risk factor for TEs across both groups (odds ratio [OR] = 4.8, 95% confidence interval [CI] = 1.3-17.6) and bleed history was a risk factor for clinically significant bleeds (OR = 6.8, 95% CI = 2.7-17.2). CONCLUSION: In this small, retrospective multicenter study, the use of DOACs did not increase the risk of TEs or clinically significant bleeds compared to warfarin in a statistically significant way.

Ripple mapping: A precise tool for atrioventricular nodal reentrant tachycardia ablation.

INTRODUCTION: Ablation for atrioventricular nodal reentrant tachycardia (AVNRT) classically utilizes evaluation of signal morphology within the anatomic region of the slow pathway (SP), which involves subjectivity. Ripple mapping (RM; CARTO-3© Biosense Webster Inc) displays each electrogram at its three-dimensional coordinate as a bar changing in length according to its voltage-time relationship. This allows prolonged, low-amplitude signals to be displayed in their entirety, helping identify propagation in low-voltage areas. We set out to evaluate the ability of RM to locate the anatomic site of the SP and assess its use in guiding ablation for AVNRT. METHODS: Patients ≤18 years with AVNRT in the EP laboratory between 2017 and 2021 were evaluated. RM was performed to define region of SP conduction in patients from 2019 to 2021, whereas standard electro-anatomical mapping was used from 2017 to 2019. All ablations were performed using cryotherapy. Demographics, outcomes, and analysis of variance in number of test lesions until success was compared between groups. RESULTS: A total of 115 patients underwent AVRNT ablation during the study; 46 patients were in the RM group and 69 were in the control group. There were no demographic differences between groups. All procedures, in both groups, were acutely successful. In RM group, 89% of first successful lesions were within 4 mm of the predicted site. There was significantly reduced variability in number of test lesions until success in the RM group (p = .01). CONCLUSION: RM is a novel technique that can help identify SP location, allowing for successful ablation of AVNRT with decreased variability.

Hope is No Plan: Uncovering Actively Missing Transition-Aged Youth with Congenital Heart Disease.

Studies describing gaps in care for youth with congenital heart disease (CHD), focus on those who have returned to care, but rarely those actively missing from care. Our objective was to determine barriers for young adults with CHD actively missing from cardiac care and to re-engage them in care. Retrospective single-center cohort study of cardiology clinic patients ages 15-21 years with CHD between 2012 and 2019 for patients actively missing from care (≥ 12 months beyond requested clinic follow-up). We conducted prospective interviews, offered clinic scheduling information, and recorded cardiac follow-up. Data analyzed using descriptive statistics, univariable, and multivariable logistic regression. Of 1053 CHD patients, 33% (n = 349) were actively missing. Of those missing, 58% were male and median age was 17 years (IQR 16-19). Forty-six percent were Non-Hispanic White, 33% Hispanic, and 9% Black. Moderately complex CHD was in 71%, and 62% had private insurance. Patients with simple CHD, older age at last encounter (18-21), and scheduled follow-up > 12 months from last encounter were more likely to be actively missing. Interviews were completed by 125 patients/parents (36%). Lack of cardiac care was reported in 52%, and common barriers included: insurance (33%), appointment scheduling (26%), and unknown ACHD center care (15%). Roughly half (55%) accepted appointment information, yet only 3% successfully returned. Many patients require assistance beyond CHD knowledge to maintain and re-engage in care. Future interventions should include scheduling assistance, focused insurance maintenance, understanding where to obtain ACHD care, and educating on need for lifelong care.

Heart Block in Unpalliated Complex Adult Congenital Heart Disease: Massive Collateral Burden Precludes Epicardial Pacemaker.

Complete heart block is a common complication for adults with congenital heart disease (CHD). Epicardial pacing is preferred in patients with septal shunting due to risk of thromboembolism. Anatomic changes in complex CHD may preclude surgical epicardial lead placement. Thromboembolism risk reduction in such patients requiring endocardial pacing remains questionable. (Level of Difficulty: Advanced.).

Improvement in Protein-Losing Enteropathy in a Patient With Fontan Circulation After Cardiac Rehabilitation and Prescriptive Exercise.

Fontan-associated protein-losing enteropathy is difficult to treat and associated with poor prognosis. Cardiac rehabilitation and exercise are thought to have beneficial effects for patients with Fontan circulation. We report the case of a young adult patient palliated to Fontan circulation, with a decade-long history of symptoms related to protein-losing enteropathy. At age 23 years, he appreciated an improvement in symptoms and laboratory values after cardiac rehabilitation and prescriptive exercise.

Epicardial Unipolar Lead Loss of Ventricular Capture during Radiofrequency Ablation of Atrial Fibrillation.

Introduction. Abnormal pacemaker behavior can occur during radiofrequency ablation. The behaviors are varied and include loss of capture. The mechanisms in this context have not been well described in the literature. We describe a case of epicardial unipolar lead loss of ventricular capture during pulmonary vein isolation. Case History. A 48-year-old man with an epicardial dual chamber pacemaker and persistent atrial fibrillation presented for radiofrequency ablation (RFA) of his abnormal rhythm. During RFA, intermittent loss of ventricular capture was witnessed. Review of the device settings prior to and after the procedure showed an increase in ventricular threshold after the procedure. Loss of capture was shown to be dependent on location and RF energy delivered. It was independent of QTc and independent of local cellular changes that would increase threshold. CONCLUSION: We hypothesize the mechanism of loss of ventricular capture in this patient with an epicardial pacemaker with unipolar leads is related to intermittent shunt of voltage from the pulse generator to the grounding pad rather than the unipolar lead.

Resolution of Hypoxia and Ascites With Percutaneous Intervention of Mustard Baffle Obstruction and Leak.

A 45-year-old man with history of Mustard repair for transposition of the great arteries, cirrhosis, and chronic hypoxemic respiratory failure presented for subacute worsening of his chronic symptoms, which were found to be secondary to a previously unrecognized baffle stenosis and leak. Percutaneous intervention resolved his ascites and hypoxia. (Level of Difficulty: Intermediate.).

Recurrent Cardiac Arrest With Negative Stress Test: An Unusual Presentation of Catecholaminergic Polymorphic Ventricular Tachycardia.

Catecholaminergic polymorphic ventricular tachycardia is a genetic disorder that causes ventricular tachyarrhythmias via increased release of intracellular calcium. The standard diagnostic measure is an exercise stress test that reveals ventricular ectopy. We present an extraordinary case marked by a normal stress test and no relation to exertion. (Level of Difficulty: Intermediate.).

Platypnea-Orthodeoxia Syndrome Caused by an Intracardiac Shunt.

Platypnea-orthodeoxia syndrome, a rare condition characterized by posture-related dyspnea, is usually caused by an intracardiac shunt, hepatopulmonary syndrome, or shunting resulting from severe pulmonary disease. We report the case of a 33-year-old woman who presented with increasing dyspnea and oxygen desaturation when she sat up or arose. Our diagnosis was platypnea-orthodeoxia syndrome. A lead of a previously implanted pacemaker exacerbated a severe tricuspid regurgitant jet that was directed toward the patient's intra-atrial septum. Percutaneous closure of a small secundum atrial septal defect eliminated right-to-left shunting and substantially improved the patient's functional status. In addition to this case, we discuss this unusual condition.

Anomalous Left Coronary Artery From the Right Sinus of Valsalva in a Patient Presenting with ST-Segment Elevation in Lead aVR: A Case Report.

BACKGROUND: Anomalous coronary artery origins appear in roughly 1% of coronary angiograms, and up to 15% of syncope and sudden cardiac death events can be attributed to anomalous coronaries. Patients with an anomalous coronary artery arising from the opposite sinus may initially present with syncope and electrocardiographic findings of ischemia. CASE REPORT: We describe a case in which an adolescent male presented with exercise-induced angina and syncope, and his initial electrocardiogram (ECG) showed diffuse ST-segment depression with ST-segment elevation in lead aVR. Cardiac catheterization revealed there was no coronary ostium in the left coronary cusp, and the left coronary artery had an anomalous origin from the right cusp. The patient received urgent left internal mammary artery-to-left anterior descending artery coronary bypass and a saphenous vein graft to the ramus intermedius. After he underwent 6 months of medical therapy with ß-blockade and angiotensin-receptor blockade, his left ventricular systolic function improved to low-normal level (left ventricular ejection fraction, approximately 50%). WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: ST-segment elevation in lead aVR is strongly prognostic for left main or triple-vessel coronary artery disease. However, in patients who present with syncope and few other coronary artery disease risk factors, this ECG finding should be suggestive of an ischemic event caused by an anomalous left coronary artery. Early recognition of this pattern of clinical signs and ECG findings by an emergency physician could be critical for making the correct diagnosis and risk stratifying the patient for early coronary angiography and urgent surgical revascularization.

Etripamil Nasal Spray for Rapid Conversion of Supraventricular Tachycardia to Sinus Rhythm.

BACKGROUND: There is no nonparenteral medication for the rapid termination of paroxysmal supraventricular tachycardia. OBJECTIVES: The purpose of this study was to assess the efficacy and safety of etripamil nasal spray, a short-acting calcium-channel blocker, for the rapid termination of paroxysmal supraventricular tachycardia (SVT). METHODS: This phase 2 study was performed during electrophysiological testing in patients with previously documented SVT who were induced into SVT prior to undergoing a catheter ablation. Patients in sustained SVT for 5 min received either placebo or 1 of 4 doses of active compound. The primary endpoint was the SVT conversion rate within 15 min of study drug administration. Secondary endpoints included time to conversion and adverse events. RESULTS: One hundred four patients were dosed. Conversion rates from SVT to sinus rhythm were between 65% and 95% in the etripamil nasal spray groups and 35% in the placebo group; the differences were statistically significant (Pearson chi-square test) in the 3 highest active compound dose groups versus placebo. In patients who converted, the median time to conversion with etripamil was <3 min. Adverse events were mostly related to the intranasal route of administration or local irritation. Reductions in blood pressure occurred predominantly in the highest etripamil dose. CONCLUSIONS: Etripamil nasal spray rapidly terminated induced SVT with a high conversion rate. The safety and efficacy results of this study provide guidance for etripamil dose selection for future studies involving self-administration of this new intranasal calcium-channel blocker in a real-world setting for the termination of SVT. (Efficacy and Safety of Intranasal MSP-2017 [Etripamil] for the Conversion of PSVT to Sinus Rhythm [NODE-1]; NCT02296190).

Early experience with intravenous sotalol in children with and without congenital heart disease.

BACKGROUND: Arrhythmias are common in the pediatric population. In patients unable to take oral medications or in need of acute therapy, options of intravenous (IV) antiarrhythmic medications are limited. Recently IV sotalol has become readily available, but experience in children is limited. OBJECTIVE: The purpose of this study was to describe our initial experience with the use of IV sotalol in the pediatric population. METHODS: A retrospective study of all pediatric patients receiving IV sotalol was performed. Patient demographic characteristics, presence of congenital heart disease, arrhythmia type, efficacy of IV sotalol use, and adverse effects were evaluated. RESULTS: A total of 47 patients (26 (55%) male and 24 (51%) with congenital heart disease) received IV sotalol at a median age of 2.05 years (interquartile range 0.07-10.03 years) and a median weight of 12.8 kg (interquartile range 3.8-34.2 kg), and 13 (28%) received IV sotalol in the acute postoperative setting. Supraventricular arrhythmias occurred in 40 patients (85%) and ventricular tachycardia in 7 (15%). Among 24 patients receiving IV sotalol for an active arrhythmia, acute termination was achieved in 21 (88%). Twenty-three patients received IV sotalol as maintenance therapy for recurrent arrhythmias owing to inability to take oral antiarrhythmic medications; 19 (83%) were controlled with sotalol monotherapy. No patient required discontinuation of IV sotalol secondary to adverse effects, proarrhythmia, or QT prolongation. CONCLUSION: IV sotalol is an effective antiarrhythmic option for pediatric patients and may be an excellent agent for acute termination of active arrhythmias. It was well tolerated, with no patient requiring discontinuation secondary to adverse effects.

Therapeutic Plasma Exchange for Urgent Rivaroxaban Reversal.

Direct oral anticoagulants, which include the factor Xa inhibitor rivaroxaban, have some advantages over vitamin K antagonists in regard to stroke prevention in patients with atrial fibrillation. However, no antidotes to reverse the effect of oral anticoagulants are commercially available, which can complicate treating patients in whom reversal is urgent. We faced this challenge in a kidney transplant candidate, a 65-year-old man with end-stage renal disease who had been taking rivaroxaban for paroxysmal atrial fibrillation. When a deceased-donor kidney became available, we needed to rapidly reduce the patient's bleeding risk, while minimizing the cold ischemic time of the donor kidney. Therefore, we decided to take an experimental approach and perform therapeutic plasma exchange. The patient's plasma anti-factor Xa level decreased from 0.4 IU/mL immediately before treatment to 0.21 IU/mL afterward, indicating that rivaroxaban had been actively removed from circulation. Waste fluid showed significant anti-Xa activity, indicating that the risk of rebound anticoagulation had been mitigated. The patient subsequently underwent successful kidney transplantation. To our knowledge, this is the first report of therapeutic plasma exchange to reverse the effects of rivaroxaban in a patient undergoing urgent surgery. This treatment may also be suitable for patients who have life-threatening, large-volume bleeding, especially in the presence of substantial kidney or liver dysfunction.