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BACKGROUNDTricuspid annular plane systolic excursion (TAPSE) has become a popular tool for assessing right ventricular (RV) systolic function because of its ease of application. TAPSE using transesophageal echocardiography (TEE) is limited by alignment with the lateral wall of the RV. Modified TAPSE (m-TAPSE) is a novel method for measuring TAPSE. m-TAPSE is the difference in the ‘apical to lateral tricuspid annulus distance’ during diastole and systole. The aim of the present study was to compare prospectively m-TAPSE with the most commonly used parameter TAPSE and near-gold standard 2D echocardiographic parameter RV fractional area change (RV FAC).METHODSWe conducted a prospective observational study of 125 consecutive patients undergoing coronary artery bypass graft surgery in a single tertiary care center. Post-anesthetic induction TAPSE was recorded using transthoracic echocardiography (TTE). m-TAPSE was recorded using TEE in the mid-esophageal four-chamber view. RV FAC was also assessed using TEE. m-TAPSE < 16 mm, TAPSE < 16 mm and RV FAC < 35% were taken as cut-offs for RV systolic dysfunction. Correlations were assessed using the Pearson correlation coefficient. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated using 2 × 2 cross table.RESULTSm-TAPSE was significantly correlated with TAPSE (r = 0.797, p < 0.001). Similarly, a significant correlation was observed between m-TAPSE and RV FAC (r = 0.602, p < 0.001). The sensitivity, specificity, PPV, NPV, and accuracy of m-TAPSE were 100%, 98.3%, 80%, 100% and 98.4%, respectively.CONCLUSIONSm-TAPSE correlated well with both RV FAC and TAPSE. Therefore, m-TAPSE can be considered an easily measurable alternative parameter for evaluating RV systolic function in a busy intraoperative setting.

Background:Lactate and central venous oxygen saturation (ScVO2) are well known biomarkers for adequacy of tissue oxygenation. Endothelin, an inflammatory marker has been associated with patient's nutritional status and degree of cyanosis. The aim of this study was to explore the hypothesis that lactate, ScVO2 and endothelin before induction may be predictive of mortality in pediatric cardiac surgery.Methods:We conducted a prospective observational study of 150 pediatric (6 months to 12 years) patients who were posted for intracardiac repair for tetralogy of fallot and measured lactate, ScVO2 and endothelin before induction (T1), 20 minutes after protamine administration (T2) and 24 hours after admission to ICU (T3).Results:Preinduction lactate and endothelin levels were found to predict mortality in patients of tetralogy of fallot with an odds ratio of 6.020 (95% CI 2.111-17.168) and 1.292(95% CI 1.091-1.531) respectively. In the ROC curve analysis for lactate at T1, the AUC was 0.713 (95% CI 0.526–0.899 P = 0.019). At the cutoff value of 1.750mmol/lt, the sensitivity and specificity for the prediction of mortality was 63.6% and 65.5%, respectively. For endothelin at T1, the AUC was 0.699 (95% CI 0.516–0.883, P = 0.028) and the cutoff value was ≤2.50 (sensitivity, 63.6%; specificity, 58.3 %). ScVO2 (odds ratio 0.85) at all three time intervals, suggested that improving ScVO2 can lead to 15% reduction in mortality.Conclusions:Lactate, ScVO2 and endothelin all showed association with mortality with lactate having the maximum prediction. Lactate was found to be an independent, reliable and cost-effective measure of prediction of mortality in patients with tetralogy of fallot.