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Magnetic resonance imaging (MRI) of patients with pacemakers remains concerning because of possible magnetic field effects on the device. Many pacemaker models are labeled as non-conditional, or contraindicated for MRI, or do not have any specific safety guidelines listed. This study describes our experience with pacemaker function and adverse events in pediatric and young adult patients after clinically indicated MRI scanning at 1.5 Tesla (T). We hypothesized that generator battery voltage, pacemaker lead threshold, and lead impedance would not be altered by MRI. This was a retrospective review of Children's Wisconsin clinical MRI data for all patients with pacemakers scanned between January 1, 2010 and March 31, 2018. Pacemakers were interrogated by the Electrophysiology Team before and immediately after MRI and at outpatient follow up. Twenty-one patients underwent forty-four MRI scans. No significant immediate changes were seen in any pacemaker parameter for any manufacturer/model/lead at the time of MRI. At first clinical follow up post MRI, (median 4.4 months, range 0.2-12.3), battery voltage was reduced (2.78 V pre-MRI versus 2.77 V at follow up, p = 0.02), but there were no other significant changes. No adverse events were noted. Pediatric patients with pacemakers, including those with epicardial leads, can be scanned at 1.5 T safely without alteration in pacemaker function. Using appropriate precautions, pediatric patients with pacemakers can be imaged with MRI.

We present our experience for patients who have undergone an anatomic repair (AR) for congenitally corrected transposition of the great arteries (CCTGA) at the Children's Hospital of Wisconsin. A retrospective chart review of patients who underwent AR for CCTGA from 2001 to 2015 was performed. The cohort consisted of 15 patients (74% male). Median age of anatomic repair was 15 months (range 4.5-45.6 months). Four patients had a bidirectional Glenn (BDG) prior to AR. At the time of AR,-9 (60%) underwent Senning/Rastelli procedure, 4 (26.6%) had double switch operation, and 2 (13.3%) underwent only Senning with VSD closure. Median duration of follow-up was 5.5 years (0.05-14 years). Reoperations prior to discharge included BDG, revision of pulmonary venous baffle, closure of residual VSD, and pacemaker placement. Late reoperations included left ventricular outflow tract obstruction repair, conduit replacement, melody valve placement, and pacemaker implantation. At their most recent follow-up, no patient had heart failure symptoms and only 1 had severely diminished function that improved with cardiac resynchronization therapy. Moderate mitral regurgitation was noted in 15% (2/13), and severe in 7% (1/13). Moderate tricuspid regurgitation was noted in 15% (2/13). One patient, 7% (1/13), developed moderate aortic insufficiency. There was a 100% survival at the time of the most recent follow-up. Patients with CCTGA who have undergone AR have excellent functional status and mid-term survival but reinterventions are common. Longer term studies are needed to determine both the extent and spectrum of reinterventions as well as long term survival.

Historically, droperidol was commonly used for postoperative sedation of critically ill children. A FDA black box warning regarding its arrhythmogenic potential greatly reduced its use. We hypothesized that administration of neuroleptic dose droperidol during volatile anesthesia would transiently prolong the corrected QT interval (QTc) in patients undergoing single ventricle palliation. As part of a prospective study in children undergoing stage 2 or 3 single ventricle palliation, we recorded electrocardiograms preoperatively, after induction of volatile anesthesia, immediately after completion of 30 min intravenous infusion of 75 mcg/kg droperidol, and shortly after arrival in the cardiac intensive care unit. Mean absolute QT intervals and heart rate data were analyzed in a blinded fashion and the longest QT interval was determined. QT intervals were corrected for heart rate (QTc) with the Bazett and Friderici formulae. Any perioperative arrhythmias were recorded. Complete data were available for 62 patients. Volatile anesthesia was associated with significant prolongation of the QTc interval. Administration of droperidol after cardiopulmonary bypass was associated with further significant QTc prolongation. All QTc changes were transient and the postoperative QTc, while still prolonged relative to baseline, was significantly shorter than the QTc immediately postdroperidol. No episodes of Torsades de Pointes (TdP) or ventricular arrhythmias were observed. The administration of a neuroleptic dose of droperidol during volatile anesthesia in patients undergoing single ventricle palliation was associated with a significant prolongation of QTc, which was transient and did not result in TdP or other ventricular arrhythmias in our study population.

Cardiac magnetic resonance imaging (CMR) for infants and young children typically requires sedation. General anesthesia with controlled ventilation can eliminate motion artifact with breath-holds during imaging to limit respiratory artifact, but these may lead to atelectasis or other complications. High-frequency oscillatory ventilation (HFOV) provides ventilation with near-constant mean airway pressure and minimal movement of chest wall and diaphragm, thus obviating the need for breath-holding. Clinical data were collected for 8 infants who underwent CMR with HFOV and 8 controls who underwent CMR with conventional ventilator and breath-hold technique. Data included demographic information, adverse events, and scan-acquisition time. Studies were reviewed for image quality by two cardiologists who were blinded to type of ventilation. There were no significant differences in patient characteristics between the two groups. There was no significant difference in average image quality for cine short-axis or black blood imaging. Total CMR scan time was not significantly different between groups, but the short-axis cine stack was acquired more quickly in the HFOV group (1.8 ± 0.8 vs. 5.0 ± 3.6 min). There were no adverse events in the HFOV group, but scans were terminated early for two patients in the conventional ventilator group. HFOV during CMR is feasible and well tolerated. Image quality is equivalent to that obtained with conventional ventilation with breath-holding technique and allows shorter cine scan times for some sequences.

Anomalous origin of the left coronary artery from the pulmonary artery (ALCAPA) is a rare congenital heart lesion that if left untreated, results in high mortality. Surgical treatment options include reimplantation of the anomalous coronary ostia, use of extracardiac arterial blood supply, or the Takeuchi procedure. The Takeuchi procedure involves creation of an aortopulmonary window and an intrapulmonary tunnel that baffles the aorta to the ostium of the anomalous left coronary artery. The incidence of late complications following the Takeuchi repair is unknown. The goal of our study was to determine the long-term outcome after palliation of ALCAPA using the Takeuchi Procedure. A total of 9 patients with a history of ALCAPA palliated with the Takeuchi procedure were identified from our surgical database. Chart review was performed. The mean age at time of Takeuchi procedure was 49.6 months (range 5 weeks-14.6 years). There was one late death, of unknown cause. Of the remaining 8 patients, the mean length of follow-up after surgery was 15.9 years (13.5-19.7 years). All 8 survivors had some degree of main pulmonary artery stenosis in the area of the intrapulmonary baffle, with moderate stenosis in 2 and severe stenosis in 1. Three late survivors (38 %) had a baffle leak. Two patients (25 %) had decreased left ventricular systolic function and 3 (38 %) had developed at least moderate mitral valve regurgitation. Three of the 8 late survivors (38 %) required a reoperation for repair of mitral valve regurgitation, baffle leak, and main pulmonary artery (MPA) stenosis. Review of literature demonstrated similar complication rates and need for reoperation following the Takeuchi procedure. Compared with patients after direct reimplantation for ALCAPA at our institution, there was no significant difference in late survival or freedom from reoperation. The Takeuchi procedure is a method to establish a two-coronary repair for ALCAPA. Late complications are common, necessitating lifelong care in a center experienced with caring for adults with congenital heart disease.