Evaluating the efficacy of the punch-out technique in systemic-to-pulmonary shunts: A computational fluid dynamics...

Systemic-to-pulmonary shunt is a palliative procedure used to decrease pulmonary blood flow in congenital heart diseases. Shunt stenosis or occlusion has been reported to be associated with mortality; therefore, the management of thrombotic complications remains a challenge for most congenital cardiovascular surgeons. Despite its importance, the optimal method for shunt anastomosis remains unclear.

The study investigates the clinical benefits of the punch-out technique over conventional methods in the anastomosis process of Systemic-to-pulmonary shunt, focusing on its potential to reduce shunt-related complications.

Anastomotic models were created by two different surgeons employing both traditional slit and innovative punch-out techniques. Computational tomography was performed to construct three-dimensional models for computational fluid dynamics (CFD) analysis. We assessed the flow pattern, helicity, magnitude of wall shear stress, and its gradient.

The anastomotic flow area was larger in the model using the punch-out technique than in the slit model. In CFD simulation, we found that using the punch-out technique decreases the likelihood of establishing a high wall shear stress distribution around the anastomosis line in the model.

The punch-out technique emerges as a promising method in SPS anastomosis, offering a reproducible and less skill-dependent alternative that potentially diminishes the risk of shunt occlusion, thereby enhancing patient outcomes.