Saline Contrast Transesophageal Echocardiography in Fontan Patients: Assessment of the Presence, Type, and Size of Right to Left Shunts.

Right to left (R-L) shunts resulting in cyanosis or systemic embolization occur after the Fontan procedure. The primary modality of diagnosing these is angiography. Successful delineation of these shunts in Fontan patients using selective saline contrast transesophageal echocardiography (SCTEE) may allow for reduced radiation and contrast exposure. We hypothesized that SCTEE could accurately determine the presence, type, and semiquantitative shunt size of R-L shunts in Fontan patients. SCTEE was performed in Fontan patients undergoing angiography for clinical indications. Injections were performed in six sites: mid-Fontan, right and left pulmonary arteries, superior and inferior vena cavae, and innominate vein. R-L shunt size was subjectively graded as 0 = absent, 1 = small, and 2 = medium or large based on echo contrast density in the left atrium. SCTEE was compared to angiography. 33 patients with Fontan were studied with median age 15 years, median weight 50.1 kg, and median O2 saturation of 90% in the R-L shunt group and 95% in the no R-L shunt group. R-L shunt types included intracardiac shunts (ICS), veno-venous collaterals (VVCs), arteriovenous malformations (AVMs), and their combinations. SCTEE versus angiography results were the same for the presence, type, and size of R-L shunts in 79% (26/33). SCTEE identified shunts in 88% (29/33). Angiography identified shunts in 85% (28/33). Neither method missed any medium or large R-L shunts. SCTEE and angiography had similar accuracy. SCTEE accurately detected the presence, type, and size of R-L shunts in most Fontan patients in this study. This can be used to guide targeted angiography, reducing radiation exposure and contrast load.

A comparison of Tei index versus systolic to diastolic ratio to detect left ventricular dysfunction in pediatric patients.

BACKGROUND: The aim of this study was to determine the accuracy, sensitivity, specificity, predictive values, and likelihood ratios of the left ventricular (LV) Tei index (TX) and the ratio of systolic duration to diastolic duration (S/D) to detect ventricular dysfunction. METHODS: LV systolic and diastolic function were studied in a cohort of 68 children, 25 normal and 43 abnormal. Systolic dysfunction was defined as the presence of all of 3 criteria: ejection fraction < 50%, fractional shortening < 27%, and tissue Doppler systolic S wave < 1.5 standard deviations below normal (Z-1.5). Diastolic dysfunction was defined as the presence of all of 3 criteria: isovolumic relaxation time corrected for heart rate > 88 ms, ratio of transmitral Doppler flow early diastolic velocity (E) to mitral valve annular early diastolic tissue Doppler velocity (E') > 13, and E' < Z-1.5. The cohort was divided into 4 groups: normal systolic and diastolic function, systolic dysfunction, diastolic dysfunction, and combined systolic and diastolic dysfunction. TX > 0.5 and S/D > 1.0 were defined as abnormal. TX and S/D results were compared with normal function versus abnormal function categories using 2 x 2 classification tables and receiver operating characteristic curves. RESULTS: The overall accuracy of TX was 85%, and that of S/D was 82%. TX was most accurate (92%) for detecting diastolic and combined dysfunction, whereas S/D had similar accuracy for all LV function groups. The overall accuracy, sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio of TX were slightly greater than those for S/D for almost all categories. CONCLUSION: The overall accuracy, sensitivity, specificity, predictive values, and likelihood ratios of TX are slightly greater than those of S/D for most categories of dysfunction, although either may fail to detect dysfunction in 15% to 18% of cases. When both TX and S/D are used in combination, using the presence of either TX > 0.5 or S/D > 1.0 as indicative of dysfunction, few cases of LV dysfunction should elude detection.

Prehypertension: detection, evaluation, and management.

Prehypertension was defined as a discrete category in 1993. There is evidence to support active management of this entity given the increased risk of hypertension, cardiovascular disease, heart failure, and stroke. There have been few comprehensive summaries on the management of this population. Therefore, this article summarizes the latest guidelines and studies on the detection, evaluation, and management of prehypertension.