Double Ventricular Response with Aberrant Conduction Leading to Ventricular Dysfunction.

Double ventricular response (DVR), where a single P wave results in two QRS complexes, is a rare presentation of dual AV node physiology. It has been associated with ventricular dysfunction in the setting of incessant tachycardia. We present the case of an otherwise healthy adolescent who had frequent DVR without tachycardia leading to left ventricular dysfunction.

Standardized Training for Physicians Practicing Pediatric Cardiac Critical Care.

Objectives: In the vast majority of Children's Hospitals, the critically ill patient can be found in one of three locations: the PICU, the neonatal ICU, and the cardiac ICU. Training, certification, and maintenance of certification for neonatology and critical care medicine are over seen by the Accreditation Council for Graduate Medical Education and American Board of Pediatrics. There is no standardization of training or oversight of certification and maintenance of certification for pediatric cardiac critical care.

Atrioventricular accessory pathways in 89 dogs: Clinical features and outcome after radiofrequency catheter ablation.

Background: Atrioventricular accessory pathways (APs) in dogs have been reported rarely. Data regarding clinical presentation and long-term outcome after radiofrequency catheter ablation (RFCA) are limited.

Hypothesis/objectives: To study clinical features, electrophysiologic characteristics, and outcome of RFCA in dogs with APs.

Utility and safety of the SafeSept™ transseptal guidewire for electrophysiology studies with catheter ablation in pediatric and congenital heart disease.

Purpose: The atrial transseptal procedure is used in catheter ablation of left-sided arrhythmias. Studies in adult patients have shown the SafeSept™ transseptal guidewire (SSTG) to be effective in atrial transseptal procedures. We analyzed our 5-year experience with SSTG use in pediatric and congenital heart disease patients undergoing catheter ablation.

Anaphylactic shock after amiodarone infusion resulting in haemodynamic collapse requiring a temporary ventricular assist device.

Acute heart failure related to anaphylactic shock is often reversible and necessitates aggressive support to ensure full recovery. We report the case of a 15-year-old boy who developed severe ventricular dysfunction and haemodynamic instability after administration of amiodarone and required temporary mechanical circulatory support with a left ventricular assist device. He had full recovery of cardiac function and returned to baseline neurologic status.

Linear lesion cryoablation for the treatment of atrioventricular nodal re-entry tachycardia in pediatrics and young adults.

Background: Radiofrequency (RF) ablation is a relatively safe and effective method for treatment of atrioventricular nodal re-entry tachycardia (AVNRT), but carries a 1-2% risk of AV nodal injury. Cryothermal ablation reduces the risk of AV block, but has had decreased procedural success and increased recurrence of tachycardia. We sought to evaluate the technique of linear lesion cryoablation (LLC) for treatment of AVNRT.

Relation of systemic venous return, pulmonary vascular resistance, and diastolic dysfunction to exercise capacity in patients with single ventricle receiving fontan palliation.

Fontan patients have a reduced exercise capacity, primarily owing to limitations in the ability to augment pulmonary blood flow and stroke volume. To date, the mechanism of peak exercise pulmonary blood flow restriction has not been elucidated. We performed a single-center, prospective, crossover trial of supine and upright exercise in Fontan patients and healthy controls to determine the mechanisms of exercise limitation in the Fontan-palliated patient.

Nodoventricular pathway associated with twin AV nodes: complexity of ablation in single ventricle physiology.

We report the case of a patient with heterotaxy syndrome including complex single ventricular morphology and interrupted IVC in association with twin conduction systems and a nodoventricular accessory pathway connection. The presence of 3 distinct QRS morphologies was inadvertently discovered during a hemodynamic catheterization study and prompted formal EP testing prior to hepatic venous inclusion into the Fontan circuit and loss of access to the atrial chamber for testing and therapy. This patient underscores the importance of close surveillance and high index of suspicion of arrhythmia mechanisms in patients with heterotaxy syndrome in conjunction with single ventricle morphology.