Extract-stent-replace for treatment of upper baffle stenosis with pacing leads after atrial switch procedures for transposition of the great arteries: An approach to avoid "jailing" the lead.

INTRODUCTION: Venous stenosis is a late complication of the atrial switch (Mustard/Senning) procedure seen in patients with transposition of the great arteries ( d-TGA). Many atrial switch patients require cardiac implantable electronic devices (CIEDs) which further increases the incidence of venous stenosis. Stenosis of the superior limb of the systemic venous pathway (SLSVP) in the presence of CIED leads presents a management challenge. We propose a method for navigating SLSVP stenosis in atrial switch patients with CIEDs. METHODS: The pulse generator and leads were removed using standard extraction techniques. Axillary access was retained via existing leads or new access was obtained. The interventional cardiology team, via groin access, performed stent-angioplasty of the stenotic SLSVP. After stent deployment, the axillary access wire was snared from below, guided through the stent, and pulled into a long groin sheath. A sheath was then advanced over the axillary wire and into the groin sheath creating a path for passage of leads through the stent. New leads were advanced through the axillary sheath into the heart. Leads were secured using standard techniques. RESULTS: All patients had a history of d-TGA and prior atrial switch procedures. In each case, there was stenosis of the SLSVP in the setting of a CIED lead. There were no immediate complications and there was no restenosis on follow-up. CONCLUSION: Post-atrial switch patients with CIEDs can develop stenosis of the SLSVP. A collaboration between electrophysiology and interventional cardiology can allow for device extraction, stent-angioplasty, and lead reimplantation to avoid "jailing" the leads.

Nonfluoroscopic Imaging as Guidance for Radiofrequency Ablation of Atrioventricular Nodal Reentrant Tachycardia after Mustard Repair.

Most tachycardias in the pulmonary venous atrium are inaccessible by direct means and require either a retrograde approach or a transseptal approach for ablation. We present a case in which successful radiofrequency ablation of common atrioventricular nodal reentrant tachycardia was accomplished via a retrograde transaortic approach guided by nonfluoroscopic mapping with use of the NavX™ mapping system. The patient was a 49-year-old woman who at the age of 4 years had undergone Mustard repair for complete dextrotransposition of the great arteries. Three-dimensional reconstructions of the ascending aorta, right ventricle, systemic venous atrium, left ventricle, and superior vena cava-inferior vena cava baffle complex were created, and the left-sided His bundle was marked. After a failed attempt at ablation from the systemic venous side, we eliminated the atrioventricular nodal reentrant tachycardia by ablation from the pulmonary venous side. This case is, to our knowledge, the first report of successful radiofrequency ablation of common atrioventricular nodal reentrant tachycardia after Mustard repair for this congenital cardiac malformation in which ablation was guided by 3-dimensional nonfluoroscopic imaging. This imaging technique enabled accurate anatomic location of the ablation catheters in relation to the His bundle marked from the systemic venous side.

Mechanisms and predictors of recurrent tachycardia after catheter ablation for d-transposition of the great arteries after the Mustard or Senning operation.

BACKGROUND: The Senning and Mustard operations for dextro-transposition of the great arteries are associated with an increased risk for supraventricular tachycardia. Catheter ablation has been shown to be acutely successful for achieving rhythm control in this population, but the mechanisms of recurrence are ill-defined. OBJECTIVE: We hypothesized that the type and degree of recurrence would vary by the surgical technique used. METHODS: All consecutive catheter ablation procedures for dextro-transposition of the great arteries after the Mustard or Senning operation between 2004 and 2016 at a single center were reviewed. Tachycardia mechanisms were determined by complete 3-dimensional mapping in addition to a standard electrophysiological technique for all cases. RESULTS: Twenty-eight patients underwent 38 procedures during the study period. The most common mechanism at the index procedure was intra-atrial reentrant tachycardia using the cavotricuspid isthmus. Over a median follow-up period of 1.6 years, 9 patients experienced recurrent tachycardia (32%), all of whom underwent repeat catheter ablation. Tachycardia recurrence was more common after the Senning vs the Mustard operation (6 of 10 [60%] vs 3 of 18 [17%]; P = .034). In addition, substrates for recurrence were different from those encountered at the index procedure in 10 of 13 tachycardias (77%), with the single most common location being the posterior anastomosis after the Senning operation. Complete control was ultimately achieved in 27 patients (96%) when considering all procedures. CONCLUSION: Recurrent tachycardia after catheter ablation appears to be more common after the Senning operation and to involve substrates unique to this repair. The posterior anastomosis is commonly implicated and should not be overlooked.

Transbaffle catheter ablation of atrial re-entrant tachycardia within the pulmonary venous atrium in adult patients with congenital heart disease.

AIMS: Catheter ablation of atrial re-entrant tachycardia in patients after atrial switch procedure for transposition of the great arteries or with a Fontan circulation is technically challenging if the critical part of the re-entry circuit is located within the pulmonary venous atrium (PVA). We report our experience in transbaffle access (TBA) to the PVA for ablation of atrial re-entrant tachycardia focusing on technical details. METHODS AND RESULTS: In eight patients, six after Mustard procedure and two with a Fontan circulation, endocardial mapping of atrial re-entrant tachycardia revealed the critical part of the re-entry circuit within the PVA. A total of 10 ablation procedures were performed. Detailed angiographic assessment of the anatomy of the systemic and pulmonary venous atria was performed prior to baffle puncture. Transbaffle access was successfully established with a standard transseptal needle in 9 of 10 procedures. No major complications occurred. At the end of the procedure and the removal of the transseptal sheath, there was no residual shunt in any patient. CONCLUSION: Transbaffle access to the PVA for ablation of atrial re-entrant tachycardia is feasible, less invasive than alternative approaches and can be safely applied in patients after Mustard procedure or with a Fontan circulation. However, the rigidity of prosthetic material may preclude baffle puncture at least in a subset of those patients.

[Cellular and biochemical contents of suspension of the laundered autologous erythrocytes, obtained using a cell saver apparatus].

Efficacy of autologous blood and residual blood laundering while cardiosurgical operations performance in a newborn babies for the inborn heart failures in conditions of artificial blood circulation, using a cell saver apparatus, was investigated. In accordance to the investigation data obtained, the efficacy of a free hemoglobin laundering have constituted 71.6%, proinflammatory interleukin-6--95.8%, loss of thrombocytes--85.8%.

Radiofrequency catheter ablation of intractable ventricular tachycardia in an infant following arterial switch operation.

A full-term male neonate presented with cyanosis upon delivery and was subsequently diagnosed with d-transposition of the great arteries, ventricular septal defect, and restrictive atrial septal defect. Following initiation of intravenous prostaglandins and balloon atrial septostomy, an arterial switch operation was performed on day 3 of life. The postoperative course was complicated by intractable ventricular tachycardia that was refractory to lidocaine, amiodarone, esmolol, fosphenytoin, and mexiletine drug therapy. Ventricular tachycardia was suppressed with overdrive atrial pacing but recurred upon discontinuation. Seven weeks postoperatively, radiofrequency catheter ablation was performed due to hemodynamically compromising persistent ventricular tachycardia refractory to medical therapy. The ventricular tachycardia was localized to the inferior-lateral right ventricular outlet septum. The procedure was successful without complications or recurrence. Antiarrhythmics were discontinued after the ablation procedure. Seven days after the ablation, a different, slower fascicular rhythm was noted to compete with the infant's sinus rhythm. This was consistent with the preablation amiodarone having reached subtherapeutic levels given its very long half-life. The patient was restarted on oral beta blockers and amiodarone. The patient was subsequently discharged home in predominantly sinus rhythm with intermittent fascicular rhythm.

Strategic and operational aspects of a transfusion-free neonatal arterial switch operation.

Blood transfusion-free complex congenital cardiac surgery in a neonate remains a challenge for multidisciplinary cardiac teams. At our institution, a 3.5 kg neonate, born to a family of Jehovah's Witnesses and postnatally diagnosed with dextro-transposition of the great arteries (d-TGA) and a small muscular ventricular septal defect, underwent a successful arterial switch operation without blood or platelet transfusion. Key points that contributed to success were optimal preoperative haematopoetic conditioning using erythropoietin and iron, a miniaturized cardiopulmonary bypass circuit including a low prime volume oxygenator and crystalloid cardioplegia, and a well-coordinated multidisciplinary team. We report an overview of the literature regarding blood transfusion-free complex congenital cardiac surgery.

[The influence of autologous umbilical cord blood and donor blood on cytokine profile of newborns with transposition of great vessels].

We investigated the serum levels ofproinflammatory and antiinflammatory cytokines (TNF-alpha, IL-1beta, IL-6, IL-8, IL-10) in newborns with transposition of the great arteries to whom during the defect correction the autologous umbilical cord blood and blood components were administered before the surgery and at the 1st, 3rd, 7th day after the surgery. We found that in the group of newborns to whom during the operation the blood components were used, the levels ofpro-inflammatory interleukins were high before surgery and at the Ist, 3rd and 7th day after it, but IL-10 was reduced. During the postoperative period, the newborns of this group had imbalance in the system cytokine, accompanied by clinical complications such as hyperthermia and pulmonary complications. Newborns with transposition of the great arteries who had the surgery using the autologous cord blood, had no significant abnormalities in serum levels cytokine before the surgery. The Ist day after surgery there was an increase in both proinflammatory and antiinflammatory cytokines. Up to 7 days the levels of interleukin gradually decreased. Newborns in this group had no postoperative complications, had an adequate immune response to the operation.

Arterial switch operation in the first hours of life using autologous umbilical cord blood.

BACKGROUND: In this study, we analyzed our clinical experience performing the arterial switch operation in the first hours of life using autologous umbilical cord blood transfusion (AUCBT). The safety and efficiency of AUCBT was assessed and compared with surgery with the use of homologous blood transfusion. METHODS: Between September 2009 and February 2011, 61 neonates underwent ASO at our institution. Patients were enrolled and allocated to two groups with different modalities of management strategies for neonates with dextrotransposition of the great arteries. RESULTS: The groups were similar in diagnoses, birth weight, cardiopulmonary bypass protocol, and surgical technique, excepting timing of surgery and blood management strategy. Preoperative mean hematocrit did not differ significantly between the groups (45% versus 45%). Mean hematocrit was significantly lower in the study group than in the control group during cardiopulmonary bypass (24% versus 31%). The hematocrit progressively increased in the study group to 38% on the first postoperative day. Serum lactate levels were higher in the study group till the second day after surgery. There were no significant differences in postoperative clinical profiles. There were no hospital deaths and no AUCBT-related side effects in our study. CONCLUSIONS: The arterial switch operation can be performed in the first hours of life with AUCBT. Therefore, AUCBT is a safe and an efficient alternative to homologous blood in neonatal open heart surgery. During the study, we also identified positive economic effects associated with this approach.

Life-threatening atrial tachycardia after the Senning operation in a patient with transposition of the great arteries.

Atrial tachycardia (AT) is recognized as a risk factor of sudden death (SD) in patients with transposition of the great arteries (TGA) after atrial switch operation. A 20-year-old man with TGA who had undergone a Senning operation experienced a near-miss SD event 1 day after appearance of AT. He was successfully resuscitated by electrical defibrillation for documented ventricular fibrillation. An electrophysiological study showed three types of AT, and all of them were terminated by radiofrequency catheter ablation (RFCA). We consider that symptomatic AT against cardiac medications is indicated for RFCA therapy.

Ablation of atrioventricular nodal reentrant tachycardia in a patient with tricuspid atresia guided by electroanatomic mapping.

We describe a case of ablation of atrioventricular nodal reentrant tachycardia in a patient with tricuspid atresia and L-malposition of great vessels using an electroanatomical mapping system integrated with cardiac magnetic resonance imaging. Atrial activation mapping during tachycardia identified the retrograde fast pathway proximal to the His bundle, observed in the left interatrial septum. Ablation was successfully completed below this area. Map integration with the patient's anatomy allowed a safe, individualized procedure.

Cryoablation of the slow atrioventricular nodal pathway via a transbaffle approach in a patient with the Mustard procedure for d-transposition of the great arteries.

The ablation of atrioventricular (AV) nodal reentrant tachycardia in patients with the Senning or Mustard procedure is quite challenging because these atrial baffle procedures isolate the AV node from systemic venous access. Cryoablation is commonly utilized for AV nodal slow pathway modification in patients with structurally normal hearts. The cryoablation technique offers the advantage of monitoring AV nodal conduction during lesions, with the ability to terminate a lesion prior to permanent injury to the AV node. This case describes the successful cryoablation of the slow AV nodal pathway via the transbaffle approach in a patient with d-transposition of the great arteries status post the Mustard procedure.

Role of magnesium in the prevention of postoperative arrhythmias in neonates and infants undergoing arterial switch operation.

The objectives of the study were to measure magnesium levels in neonates and infants undergoing arterial switch operation and to ascertain the role of magnesium supplementation in the prevention of postoperative arrhythmias. Group I (n=25): magnesium was administered in the dose of 30 mg/kg over 10 minutes in normal saline (5 ml) immediately after cessation of cardiopulmonary bypass (CPB). Group II (n=25): normal saline (5 ml) was administered over 10 minutes immediately after cessation of CPB. Samples of arterial blood were collected at four time points: 1) after induction of anaesthesia; 2) 10 minutes after initiation of CPB; 3) at rewarming during CPB; and 4) 4 hours after shifting the patient to the intensive care unit. Samples were measured for ionized magnesium (iMg), blood gases, haematocrit level, electrolytes, ionized calcium and glucose. Continuous ECG rhythm analysis and documentation of arrhythmias was performed for 24 hours after surgery. The mean preoperative iMg levels were below the normal level in both the groups. A significant increase in iMg levels (P=0.00) was seen in both groups during rewarming. There is no statistically significant difference in the incidence of arrhythmias between the magnesium supplemented group (4%) and the control group (20%) in the postoperative period, a tendency towards reduction in arrhythmias was only observed in the magnesium supplemented group.

Optimization of myocardial strain imaging and speckle tracking for resynchronization after congenital heart surgery in children.

Cardiac resynchronization therapy can improve cardiac function in children with heart failure. The optimal method of assessing dyssynchrony has not been established. Newer tissue Doppler techniques such as strain assessment and speckle tracking appear to be promising for optimization of resynchronization. Two children aged 7 weeks and 4 months, with transposition of the great arteries and ventricular septal defect, and double outlet right ventricle with pulmonary stenosis, developed heart block after surgery. Conventional epicardial pacing resulted in heart failure in both. Upgrade to cardiac resynchronization therapy was not associated with normalization of function by echo, necessitating optimization. Baseline ventriculo-ventricular delay was 4 ms. Speckle tracking strain assessment was performed while adjusting ventriculo-ventricular delay. In Patient 1, synchrony was best with left ventricular (LV) activation preceding right ventricular (RV) by 30 ms. In Patient 2, it was best with RV preceding LV by 20 ms. At follow-up, both patients had normalization of function. In each case, optimization and reprogramming could be done live with no need for offline analysis. Speckle tracking strain analysis appears to be successful in the live, on-site optimization of cardiac resynchronization therapy in children. Further studies may help refine this process further.

Transfusion-free arterial switch operation in a 1.7-kg premature neonate using a new miniature cardiopulmonary bypass system.

In cardiac surgery, the potentially detrimental effects of transfusions on patient outcome are increasingly appreciated. Therefore, at our institution there are continuing efforts to modify our surgical, perfusion, and blood management strategies with the aim of transfusion-free cardiac surgery even in neonates and small children. Stringent improvement of these strategies, particularly the downsizing of the cardiopulmonary bypass system, have now enabled a transfusion-free arterial switch operation in a 1700-gram prematurely born neonate.