Hypoplastic right lung associated with right pulmonary vein stenosis and systemic collateral.

We present a case of a 6-month-old girl diagnosed as unilateral pulmonary vein stenosis (right inferior pulmonary vein) with dextroposition of the heart, hypoplastic right lung, hypoplastic right pulmonary artery, collateral from the descending aorta supplied right lower lung, connection between collateral and right pulmonary artery with retrograde flow from right pulmonary artery into main pulmonary artery, and right superior and middle pulmonary vein agenesis. A combined modality of imaging including chest film, echocardiography, multidetector computerized tomography, and the cardiac catheterization nicely demonstrated all of the unique and rare congenital abnormalities.

Counter intuitive relations between in vivo RF lesion size, power, and tip temperature.

Background: Radiofrequency (RF) lesion size in vitro is positively correlated with applied power and catheter tip temperature. However, the relation between RF lesion size, power, and tip temperature in vivo remains unclear. We hypothesized that due to flow, anatomy and tip contact effects in vivo, increased tip temperature would be inversely related to applied power and RF lesion size.

Bidirectional ventricular tachycardia and channelopathy.

Based on similarity of electrocardiographic features, bidirectional ventricular tachycardia has been considered a variant of long QT syndrome. Genes causing long QT syndrome were used as candidate genes in 4 patients with bidirectional ventricular tachycardia. In 2 patients, we identified a common low penetrance HERG allele (R1047L) with an intermediate biophysical phenotype.

Ventricular tachycardia in nonpostoperative pediatric patients: role of radiofrequency catheter ablation.

Experience concerning radiofrequency catheter ablation (RFCA) of ventricular tachycardia (VT) in pediatric patients is limited. In adults, success rates vary widely based on the etiology of the VT. Highest success rates have been achieved in patients without structural heart disease.

Catheter tip cooling during radiofrequency ablation of intra-atrial reentry: effects on power, temperature, and impedance.

Introduction: Cooling the catheter tip either passively with increased tip size or actively during radiofrequency catheter ablation (RFCA) has been shown in canine thigh preparations to create larger lesions than standard catheter tips, yielding a theoretical advantage for improving the outcome of RFCA for intra-atrial reentrant tachycardia (IART).

Methods And Results: The pediatric RFCA database at the Medical University of South Carolina was reviewed for RFCA of IART in patients with structural heart disease. From a total of 31 patients who underwent procedures during the study period, 8 patients in whom ablation with conventional ablation techniques failed and who went on to passive cooling with an 8-mm tip catheter or active cooling with an internally cooled-tip catheter were studied.