Low incidence of significant valvar insufficiency following retrograde aortic radiofrequency catheter ablation in young patients.

The incidence of significant valvar insufficiency at late (<6 month) follow-up was retrospectively evaluated in 27 young patients (age 4. 0-18.0 years) undergoing 29 ablation procedures via the retrograde aortic approach for left-sided accessory connections in whom pre-ablation and post-ablation echocardiograms were available for review. Valvar insufficiency was graded using color flow techniques as absent, trivial, mild, moderate, or severe by blinded reviewers. Ablation was acutely successful via the retrograde approach in 25 of 29 procedures among these 27 patients. Successful ablation was ultimately achieved in all 27 patients. At baseline, 7 patients had evidence of trivial or mild mitral insufficiency, and no patient had aortic insufficiency. Three patients had evidence of impaired left ventricular systolic performance in the presence of manifest pre-excitation. At follow-up, pre-existing mitral insufficiency resolved in 5/7 patients, and persisted in 2 patients. New mitral insufficiency was evident in 3 patients, and new aortic insufficiency was transiently evident in 1 patient following ablation (all trivial). Institutional experience (mean rank 10 cases vs. 33 cases, p <.0005), and lower patient weight (29.7 vs. 56.3 kilograms, p =.01) were the only factors associated with the development of new valvar insufficiency. Valvar insufficiency could not be detected by careful auscultation in any patient and was deemed clinically insignificant in all patients. We conclude that ablation of left-sided accessory connections can be performed via the retrograde aortic approach without creating clinically significant valvar insufficiency.

Quantifying and minimizing radiation exposure during pediatric cardiac catheterization.

This study reports findings from evaluations of new technologies to measure radiation exposure during pediatric cardiac catheterization procedures. A strategy of pulsed fluoroscopy and low power settings resulted in significantly lower patient radiation exposure compared to conventional 60 frames/sec, high-power settings during fluoroscopy. During radiofrequency ablation procedures, thyroid and thoracic skin sites outside the direct fluoroscopic field received minimal radiation exposure. Intrathoracic radiation exposure was measured with the use of an esophageal dosimeter. In conclusion, strategies to reduce total radiation exposure should be employed, radiation dose should be measured, and assessment of radiation skin injury should be included in post-catheterization assessment.

The role of radiofrequency ablation for pediatric supraventricular tachycardia.

Radiofrequency ablation has become frontline therapy for many pediatric patients with common supraventricular tachycardia (SVTs). Rather than long-term treatment with medications, radiofrequency ablation offers the possibility of "cure" for certain SVT substrates. The decision to perform radiofrequency ablation should be made after full disclosure with the patient and parents about radiofrequency ablation (RFA) benefits and risk, alternative therapies, and the natural history of the SVT. This paper presents a discussion about the current status of RFA and common pediatric SVTs, as well as, discussing evolving RFA issues and indications.

Percutaneous stent placement as treatment for an infant with superior vena cava syndrome.

The percutaneous use of stents for the treatment of superior vena cava (SVC) syndrome is well described in the adult population. We report the successful use of intravascular stents to treat an infant with severe SVC syndrome.

Relief of right ventricular to pulmonary artery conduit stenosis using a self-expanding stent.

Intravascular stents have recently been used to treat vascular stenoses in congenital heart disease. Size limitations, however, may preclude their use in certain situations. We describe the successful relief of right ventricular to pulmonary artery conduit stenosis in an adult patient late after repair of truncus arteriosus using a larger, self-expanding wall stent.