Perventricular closure of multiple muscular ventricular septal defects is safe and effective. We believe that this could become the treatment of choice for any infant with muscular ventricular septal defects or any child with muscular ventricular septal defect and associated cardiac defects.

Stent patients had significantly lower acute complications compared with surgery patients or BA patients, although they were more likely to require a planned reintervention. At short-term and intermediate follow-up, stent and surgical patients achieved superior hemodynamic and integrated aortic arch imaging outcomes compared with BA patients. Because of the nonrandomized nature of this study, these results should be interpreted with caution.

The medical and surgical management of patients with multiple muscular ventricular septal defects (VSDs) is associated with morbidity and mortality. Three children with Swiss cheese VSDs were treated with transcatheter occlusion of their multiple defects using the Amplatzer muscular VSD occluder. Seventeen defects were closed in five catheterization procedures. One patient had three devices placed in two procedures, the second had five defects closed in one procedure, and the third had nine defects closed in two procedures. Two patients had previously been treated with pulmonary artery banding and required subsequent surgical band removal. There was immediate reduction in the left-to-right shunting and clinical improvement in all patients. Complications included the need for blood transfusion during the two longest procedures and tricuspid valve regurgitation in one. Transcatheter occlusion of multiple VSDs is an acceptable alternative or adjunct to surgical therapy for these complex patients.

The feasibility of noninvasively assessing hemoglobin oxygen saturation of deep blood vessels in vivo by measuring blood T2* is investigated. Techniques for blood T2* measurements in major arteries and veins in the presence of pulsatile blood flow are presented and validated using a flow phantom. Images of multiple TEs were collected in a paired fashion. Cardiac triggering was used to eliminate image artifacts caused by pulsatile arterial blood flow. Using these techniques, it was found that the T2* of arterial blood (199 +/- 8 ms) is significantly greater than that of venous blood (108 +/- 6 ms) in 10 volunteers, consistent with the fact that the oxygen saturation level of arterial blood is much larger than that of venous blood. Various oxygen saturation levels were created in vivo in a pig and the blood T2* was shown to increase with oxygen saturation levels over a wide range. Preliminary results of this study indicate that it is feasible to assess local oxygen saturation by measuring blood T2* using the proposed techniques.

Transesophageal echocardiography (TEE) has been employed successfully for guiding transcatheter device closure of secundum atrial septal defect (ASD) and patent foramen ovale (PFO). However, the use of TEE for device closure requires general anesthesia. Intracardiac echocardiography (ICE) can provide similar anatomical views that might replace the use of TEE for device closure. Eleven patients (eight female/three male) with secundum ASD and PFO associated with strokes underwent attempts at transcatheter closure of their defects under sequential TEE and ICE guidance (six patients) and under ICE alone (five patients). The ages of the patients ranged from 6.6 to 74.7 yr, and their weights ranged from 23 to 124.5 kg. The sizes of the defects, as measured by TEE (six patients), ranged from 3 to 27 mm and, as measured by ICE (11 patients), from 3 to 27 mm. The balloon-stretched diameter of the ASD, as measured by TEE (six patients), ranged from 16 to 38 mm and, as measured by ICE (11 patients), from 16 to 35 mm. Both techniques correlated well for the measured two-dimensional diameter and for the balloon-stretched diameter (r ‫؍‬ 0.97 and 0.98, respectively). Both TEE and ICE provided similar views of the defects and the various stages of device deployment. Owing to the proximity of the left atrium to the esophagus, however, the images obtained by ICE were more helpful and informative than those obtained by TEE. All patients experienced successful device placement (six patients under both TEE and ICE; five patients under ICE guidance alone); complete closure of the defects was effected in nine patients, whereas two patients had small residual shunts. There were no complications. We conclude that ICE provides unique images of the atrial communications and measurements similar to those obtained by TEE. ICE potentially could replace TEE as a guiding imaging tool for ASD and PFO device closure, thus eliminating the need for general anesthesia.