Pulmonary Venous Gradients in Healthy Controls and Following the Repair of Total Anomalous Pulmonary Venous Return.

The percent of children who can achieve a normal and physiologic pulmonary venous gradient and flow following the repair of Total Anomalous Pulmonary Venous Return (TAPVR) is not known. Pulmonary venous confluence gradients from infants with supra-, infra-, or mixed TAPVR, repaired using a direct anastomotic connection were measured. Data from age, weight, and gender-matched controls established the normal pulmonary venous gradient range (0.30-0.94 mmHg). TAPVR subjects were divided into three groups: (I) pulmonary venous gradient < 2 × normal with multiphasic flow (II) pulmonary venous gradient > 2 × normal with multiphasic flow, and (III) pulmonary venous gradient > 2 × normal with monophasic flow. From 63 children following TAPVR repair and 63 matched controls, pulmonary venous gradients were significantly lower [0.5 mmHg (IQR:0.4, 0.6) vs 1.6 mmHg (IQR:1.0, 2.4); p < 0.001], and multiphasic flow more frequent (100 vs. 84.1%; p = 0.001) within the control group. There were 38 children (60.3%) in group I, 15 (23.8%) in group II, and 10 (15.8%) in group III. Children in Group I were significantly older at the time of repair, had shorter cardiopulmonary bypass times, and did not utilize deep hypothermic circulatory arrest (DHCA). Multivariate analysis confirmed that avoiding DHCA [Odds Ratio 0.931 (0.913,0.994; p = 0.002)] and shorter cardiopulmonary bypass times [Odds Ratio 0.962 (0.861,0.968; p = 0.02)] during repair were associated with the lowest pulmonary venous gradients and multiphasic flow. Following TAPVR repair with a direct anastomosis, the majority of children can achieve a gradient two times normal or less with multiphasic pulmonary venous flow.