Outcome of Obstructed Total Anamalous Pulmonary Venous Connection (TAPVC) Repair Patients with Milrinone Versus Milrinone and Inhaled Nitric Oxide (INO): A Prospective Randomized Observational Study

To the Editor, I read with great interest the article “Outcome of Obstructed Total Anomalous Pulmonary Venous Connection (TAPVC) Repair Patients with Milrinone Versus Milrinone, and Inhaled Nitric Oxide (INO): A Prospective Randomized Observational Study,” which was published by Srikanth Gujja et al.[1] in Annals of Cardiac Anesthesia. Approximately 15% of cases diagnosed with total anomalous pulmonary venous return (TAPVR) may be suffered from narrowing at the any level of vertical vein (VV), which may responsible for pulmonary hypertension and postoperative pulmonary hypertensive crisis.[2] According to the some surgeons, the decision-making of whether the vertical vein must be closed or leave open can be determined perioperatively by temporary occlusion of vertical vein after the cardio-pulmonary by-pass. After the temporary occlusion of vertical vein, the left atrial pressure and mean pulmonary artery pressure may elevate. This means that, after the total surgical correction of TAPVR, the compliance of the left heart chambers, have not been able to accept the oxygenated blood coming from the lungs. In this situation unlighted vertical vein serves as a reservoir decompressing the left heart chambers. In other words, the left atrium and the left ventricle have not been in the mod to be able to maintain the cardiac output yet, this means vertical vein acts as a vent, if the left atrium is small and the vertical vein should be left open. However, according to some author, it is reasonable that vertical vein must be ligated in all patients operated due to TAPVR to be able to avoid negative effect of residual left-to-right shunt. According to some surgeons Yet, the necessity of closure of this venous channel in a routine fashion at the time of TAPVR repair is still controversial in the surgical world.[3,4] Cope et al. postulated that leaving open VV can reduce the early mortality rate, and concluded that the VV can be closed percutaneously after the primer operation. Moreover, in some patients VV can be closed spontaneously. However, although there is no more information about the surgical technique which is used in this study, unlighted vertical vein plays a major role in decompressing the left heart chambers when pulmonary hypertensive crisis occurs after the operations. At the same time, unlighted vertical vein acts as a reservoir in patients who have low left heart chambers compliance which allows the left heart chambers to adopt the new hemodynamic situation created after operation. And in the light of knowledge mentioned above, vertical vein should be left open in patients with obstructed type supracervical TAPVR.[5] As mentioned in the article, to deal with pulmonary hypertensive crisis, pulmonary artery vasodilators like milrinone or nitric oxide can be used after the operation in the intensive care unit period. Use of Intravenous prostacyclin-analogs like epoprostenol, Treprostinil, iloprost also should be kept in mind so as to deal with pulmonary hypertension.[6] Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.