Impact of pulmonary artery size on early haemodynamic and laboratory variables following total cavopulmonary...

Current research suggests that a small pulmonary artery can cause adverse events and reduce exercise capacity after the Fontan procedure. This study aimed to evaluate the impact of pulmonary artery size on early haemodynamic and laboratory variables after total cavopulmonary connection.

We reviewed all patients who underwent staged Fontan between 2012 and 2022. Pulmonary artery index before bidirectional cavopulmonary shunt and before total cavopulmonary connection was calculated according to Nakata and colleagues. We sought to analyse the impact of the pulmonary artery index on early haemodynamic and laboratory variables, including pulmonary artery pressure and mean arterial pressure 12 hours after extubation and lactate levels 6 hours after extubation.

A total of 263 patients were included. Median age and weight at total cavopulmonary connection were 2.2 (interquartile ranges: 1.8-2.7) years and 11.7 (interquartile range: 10.7-13.3) kg, respectively. Before that, all patients underwent bidirectional cavopulmonary shunt at a median age of 4.1 (interquartile range: 3.2-5.8) months. In the multivariable analysis, pre-bidirectional cavopulmonary shunt pulmonary artery index (p = 0.016, odds ratio 0.993), with a cut-off value of 154 mm²/m² was an independent risk factor for a higher pulmonary artery pressure (> 17 mmHg). No variable was identified as a significant risk factor for lower mean arterial pressure (< 57 mmHg). Regarding lactate levels (> 4.5 mg/dl), pre-bidirectional cavopulmonary shunt right pulmonary artery index (p < 0.001, odds ratio 0.983), with a cut-off value of 70 mm²/m² was identified as an independent risk factor.

In patients with staged Fontan palliation, a small pulmonary artery size before bidirectional cavopulmonary shunt and total cavopulmonary connection was a determinant factor associated with unfavourable early postoperative haemodynamics after total cavopulmonary connection.