Sequelae after modified Fontan operation: postoperative haemodynamic data and organ function.

Abstract

Objective-To investigate the specific sequelae of the Fontan operation, and particularly the potential sequelae of chronically elevated systemic venous pressure. Design-A retrospective analysis of clinical and haemodynamic data and evaluation of organ function in 80 surviving patients undergoing modified Fontan operation for various forms of underlying functionally univentricular hearts. Patients-65 patients (81%) who had undergone a total cavopulmonary anastomosis and 15 an atriopulmonary anastomosis. Follow up ranged from 12 to 106 months (mean 54 (SD 23) months). Results-62 patients underwent postoperative cardiac catheterisation (mean systemic venous pressure 10-5 (2.5) mm Hg and cardiac index 3-1 (0.7) 1lmin/m2). Older age at operation was significantly correlated with both higher systemic venous pressure and lower cardiac index. Atrial arrhythmia was documented on Holter electrocardiogram in 17%. Protein losing enteropathy (with abnormal a,-antitrypsin clearance) was found in 2/80 patients (2.5%). Ten patients had hypoproteinaemia, with a significantly higher incidence in patients after total cavopulmonary anastomosis and young age at operation. Liver function tests reflecting liver synthesis and metabolism were normal in all, whereas mild cholestasis was found in nearly 300/o-predominantly in patients with a cardiac index of < 3 I/min/m2 (P = 0 045). Five patients (6.2%) developed atrial thrombosis. Coagulation factor analysis in 44 patients showed protein C deficiency in 11 (25%); laboratory signs of activation of the coagulation system were found in four of these (9%). None of the abnormal laboratory indices was significantly related to underlying cardiac malformation, postoperative systemic venous pressure, or follow up interval.Conclusions-A high proportion of clinically asymptomatic patients had abnormal laboratory findings on mid-term follow up. Detailed evaluation of organ function is necessary to detect the need for further diagnostic procedures before clinical symptoms develop. (Heart 1997;78:154-159)

Coagulation profile and liver function in 102 patients after total cavopulmonary connection at mid term follow up

“…It was also noted in other studies that patients with cholestasis after the Fontan procedure were significantly older and had longer follow up, 7 as well as a lower cardiac index and increased central venous pressure. 1 The risk of spontaneous thrombus formation is increased in patients with Fontan physiology, since some venous blood stasis is always present. In an extensive review, Monagle and colleagues 20 noted a frequency of thrombotic events ranging from 3-20% after the Fontan procedures.…”

VKORC1 and CYP2C9 genotype and patient characteristics explain a large proportion of the variability in warfarin dose requirement among children

“…The mechanism for the lower dose requirement may be related to abnormal liver function, resulting in reduced warfarin metabolism. 23 Although all of the children in our cohort who had a Fontan procedure were anticoagulated with the lower target INR range of 2.0 to 3.0, target INR range was not an independent variable in terms of its effect on warfarin dose requirement.…”

Older Age at Completion of Fontan Procedure Is Associated with Improved Percentage of Predicted Maximum Oxygen Uptake

“…Although the Fontan surgical approach results in a stable physiology, there are attendant circulatory disadvantages, including elevated central venous pressures, 10 reduced ventricular filling, 11,12 and overall decreased cardiac output. 13 During exertion, these shortcomings are intensified.…”