Bradley C. Clark

Myocardial Ischemia Secondary to Synthetic Cannabinoid (K2) Use in Pediatric Patients

K2 is a synthetic cannabinoid that has potential cardiovascular side effects, including myocardial ischemia, myocardial infarction, and arrhythmias. Cardiac testing of pediatric patients is often not performed owing to a lack of symptomatology. We report a series of pediatric patients with concern for myocardial ischemia temporally associated with K2 exposure.

Minimally invasive percutaneous pericardial ICD placement in an infant piglet model: Head-to-head comparison with an open surgical thoracotomy approach.

BACKGROUND Epicardial implantable cardioverter-defibrillator (ICD) placement in infants, children, and patients with complex cardiac anatomy requires an open surgical thoracotomy and is associated with increased pain, longer length of stay, and higher cost. OBJECTIVE The purpose of this study was to compare an open surgical epicardial placement approach with percutaneous pericardial placement of an ICD lead system in an infant piglet model. METHODS Animals underwent either epicardial placement by direct suture fixation through a left thoracotomy or minimally invasive pericardial placement with thoracoscopic visualization. Initial lead testing and defibrillation threshold testing (DFT) were performed. After the 2-week survival period, repeat lead testing and DFT were performed before euthanasia. RESULTS Minimally invasive placement was performed in 8 piglets and open surgical placement in 7 piglets without procedural morbidity or mortality. The mean initial DFT value was 10.5 J (range 3-28 J) in the minimally invasive group and 10.0 J (range 5-35 J) in the open surgical group (P = .90). After the survival period, the mean DFT value was 12.0 J (range 3-20 J) in the minimally invasive group and 12.3 J (range 3-35 J) in the open surgical group (P = .95). All lead and shock impedances, R-wave amplitudes, and ventricular pacing thresholds remained stable throughout the survival period. CONCLUSION Compared with open surgical epicardial ICD lead placement, minimally invasive pericardial placement demonstrates an equivalent ability to effectively defibrillate the heart and has demonstrated similar lead stability. With continued technical development and operator experience, the minimally invasive method may provide a viable alternative to epicardial ICD lead placement in infants, children, and adults at risk of sudden cardiac death.

Single-incision percutaneous pericardial icd lead placement in a piglet model

Our group has demonstrated the feasibility of percutaneous pericardial ICD lead placement in a piglet model utilizing direct visualization from a lateral thoracoscopic approach. Development of a novel delivery tool that incorporates visualization allows for the procedure to be performed with a 1 cm subxiphoid incision.

Transvenous nonfluoroscopic pacemaker implantation during pregnancy guided by 3-dimensional electroanatomic mapping

Introduction Patients with congenital heart disease are at ongoing risk of developing both bradyarrhythmias and tachyarrhythmias decades after surgical repair. Rarely, arrhythmias can be exacerbated during pregnancy and require emergent intervention. Here, we report unique experience with nonfluoroscopic pacemaker implantation during pregnancy. Ionizing radiation, even in low doses, is associated with an increased risk of malignancy, and a fetus may be at particularly increased risk. Over the past 2 decades, the use of fluoroscopy in cardiac ablation procedures has become nearly obsolete with the development of 3-dimensional (3D) electroanatomic mapping software such as CARTO (Biosense-Webster, Diamond Bar, CA) and NavX or EnSite (St. JudeMedical, Inc., St. Paul, MN). However, certain procedures, such as device implants, still commonly use fluoroscopy in most instances. Fluoroscopy use in patients with congenital heart disease is of utmost concern because of cumulative radiation exposure from multiple lifetime catheterization, radiographic and computed tomography imaging, and electrophysiological procedures.

Arrhythmia diagnosis and management throughout life in congenital heart disease

ABSTRACT Arrhythmias, covering bradycardia and tachycardia, occur in association with congenital heart disease (CHD) and as a consequence of surgical repair. Symptomatic bradycardia can occur due to sinus node dysfunction or atrioventricular block secondary to either unrepaired CHD or surgical repair in the area of the conduction system. Tachyarrhythmias are common in repaired CHD due to scar formation, chamber distension or increased chamber pressure, all potentially leading to abnormal automaticity and heterogeneous conduction properties as a substrate for re-entry. Atrial arrhythmias occur more frequently, but ventricular tachyarrhythmias may be associated with an increased risk of sudden cardiac death, notably in patients with repaired tetralogy of Fallot or aortic stenosis. Defibrillator implantation provides life-saving electrical therapy for hemodynamically unstable arrhythmias. Ablation procedures with 3D electroanatomic mapping technology offer a viable alternative to pharmacologic or device therapy. Advances in electrophysiology have allowed for successful management of arrhythmias in patients with congenital heart disease.

Cardiac arrest in an adolescent with Uhl’s anomaly: Two unusual cardiac arrhythmia mechanisms

Introduction Uhl’s disease is a rare congenital cardiac anomaly characterized by partial or complete absence of the right ventricular free wall myocardium, which is replaced by fibroelastic and adipose tissue. Complications that result can be divided into either right ventricular dysfunction with congestive heart failure, or arrhythmias. While ventricular arrhythmias predominate, there are case reports of atrial flutter, intra-atrial reentry tachycardia, atrioventricular (AV) block, and bilateral bundle branch block. Sudden cardiac death has been reported in patients with Uhl’s anomaly. Herein we report an adolescent patient with out-ofhospital cardiac arrest with 2 unusual arrhythmia mechanisms. What are the mechanisms for these 2 arrhythmias?

Selective use of the electrocardiogram in pediatric preparticipation athletic examinations among pediatric primary care providers.

Recent literature examining insurance administrative data suggests that a selective approach, with concurrent history and physical exam (H&P), for obtaining an electrocardiogram (ECG) as a part of a preparticipation examination (PPE) for pediatric athletes is commonly used in the primary care setting demonstrating a high rate of disease detection. We sought to understand practice patterns of providers with regard to usage of ECG as a part of PPE.