Echocardiographic Assessment of Pulmonary Arteries Pulsatility Index in Fontan Circulation

BACKGROUND: Late complications after Fontan procedure may be due to the absence of pump and pulsatile pulmonary blood flow in this type of palliation. Our aim was to quantify the degree of pulsation by echocardiographic method in patients with extracardiac total cavopulmonary connection (ECTCPC) in comparison with biventricular circulation and few cases of pulsatile Fontan. METHODS: In a case series study, pulsatility index (PI) derived by echocardiographic method were compared between 20 patients with ECTCPC, 6 patients with pulsatile Fontan and 18 normal individual aged 4 to 20 years old. All patients were in New York Heart Association class of I and there was no report of complication. RESULTS: In patients with ECTCPC pulmonary artery branches Doppler flow study showed lower peak and mean velocities compared to the pulsatile Fontan and normal groups. ECTCPC patients had PI of 0.59 +/- 0.14 and 0.59 +/- 0.09 for right and left pulmonary arteries (RPA and LPA) respectively. PI was higher in patients with preserved antegrade flow (RPA PI = 0.94 +/- 0.26, LPA PI = 0.98 +/- 0.27) and in normal individuals (RPA PI = 1.59 +/- 0.12, LPA PI = 1.64 +/- 0.17) for both branches (p = 0.000). CONCLUSION: Using a Doppler derived index for pulsatility, patients with ECTCPC had the least pulsation. The pulmonary artery flow pattern in patients with preserved antegrade flow showed higher pulsatility indices in both branches. Normal individuals had the greatest pulsatility index.

Risk factors for post-cardiac surgery diaphragmatic paralysis in children with congenital heart disease

Injured phrenic nerve secondary to cardiac surgeries is the most common cause of diaphragmatic paralysis [DP] in infants. The aim of this study was to determine the risk factors for DP caused by congenital heart defect corrective surgeries in pediatrics. This cross-sectional study, conducted in a 2-year period [2006-2008], included 451 children with congenital heart diseases admitted to the Pediatric Cardiac Surgery Ward of Imam Khomeini Hospital. The diaphragmatic function was examined via fluoroscopy, and the frequency of DP and its relevant parameters were evaluated. Of the 451 patients, comprising 268 males and 183 females at an age range of 3 days to 204 months [28.2 +/- 33.4 months], 25 [5.5%] infants [60% male and 40% female, age range = 15 days to 132 months, 41.2 +/- 28.1 months] had DP as follows: 48% unilateral right-sided and 36% unilateral left-sided. Additionally, 68% had cyanotic congenital heart disease and 84% had DP following total correction surgery. The highest prevalence rates of DP resulting in phrenic hemiparesis were observed after arterial switch operation, Fontan procedure, and Blalock-Taussig shunt surgery, respectively. Thirteen [52%] of the 25 DP patients underwent surgical diaphragmatic plication because of severe respiratory distress and dependency on mechanical ventilation, and most of the cases of plication underwent arterial switch operation. The rate of mortality was 24% [6 patients]. DP with a prevalence of 5.5% was one of the most common complications secondary to cardiac surgeries in the infants included in the present study. Effective factors were age, weight, cyanotic congenital heart defects, and previous cardiac surgery. Diaphragmatic plication improved prognosis in severe cases