Journal of Rare Cardiovascular Diseases

Background: The aim of Fontan procedure is to restore a balance between pulmonary and systemic circulation and improve or nearly normalize arterial saturation in patients with functionally univentricular heart. Nevertheless, due to the lack of subpulmonary pump, the circulatory system becomes haemodynamically less efficient, what can lead to the impairment of exercise capacity. Aim: The aim of the study was to investigate exercise capacity by means of cardiopulmonary exercise test and pulmonary function tests, of 37 adult Fontan patients with regard to the time passed from the index procedure. The patients were divided into 3 groups: group I – up to 15 years post procedure; group II – 16–20 years, group III – more than 20 years after Fontan procedure). Results: 37 Fontan patients (mean age was 24.4 ±5.7 years, 40% of women) were enrolled in the study. The mean postoperative time was 19.4 ±5.1 (13–30) years. Mean, peak oxygen consumption (VO2peak) was 22.7 ±7.1 ml/kg/min (64.2 ±18.5% of predicted value). According to postoperative time a significant increase of ventilatory equivalent of carbon dioxide (VE/VCO2) (p = 0.033) and significant decrease of forced expiratory volume in 1 s/ vital capacity (FEV1%VC) between group 2 and 3 (p = 0.026) were observed. Additionally, the age of the patients correlated negatively with and heart rate (HR) (r = -0.360, p <0.05) and peak oxygen consumption (VO2peak) (r = -0,337, p < 0.05). Moreover, age at Fontan operation and time after Fontan procedure was related to ventilator equivalent of oxygen (VE/VO2) (r = -0,343, p <0.05, and r = 0.393, p <0.05). Single ventricle ejection fraction (SVEF) and atrioventricular regurgitation degree did not corresponded with cardiopulmonary exercise test (CPET) values. Conclusions: Results highlight the complex problem of diminished exercise capacity of Fontan patients depending on the time passed from the procedure. Exercise tolerance deteriorates in time: VE/VCO2 increases, FEV1/VC markedly lowers in a group of Fontan patients at 20 years follow-up. JRCD 2016; 2 (8): 254–258

rare disease, Fontan procedure; cardiopulmonary exercise test; pulmonary function test

Fontan F, Baudet E. Surgical repair of tricuspid atresia. Thorax 1971;26:240–248.

Zając A, Tomkiewicz L, Podolec P, et al. Cardiorespiratory response to exercise in children after modified Fontan operation. Scand Cardiovasc J SCJ 2002;36:80–85.

Hebert A, Jensen AS, Mikkelsen UR, et al. Hemodynamic causes of exercise intolerance in Fontan patients. Int J Cardiol 2014; 175: 478–483.

Matthews IL, Fredriksen PM, Bjørnstad PG, et al. Reduced pulmonary function in children with the Fontan circulation affects their exercise capacity. Cardiol Young 2006; 16: 261–267.

Tomkiewicz-Pajak L, Podolec P, Drabik L, et al. Single ventricle function and exercise tolerance in adult patients after Fontan operation. Acta Cardiol 2014; 69: 155–160.

Bidart CM, Abbas AE, Parish JM, et al. The noninvasive evaluation of exercise-induced changes in pulmonary artery pressure and pulmonary vascular resistance. J Am Soc Echocardiogr Off Publ Am Soc Echocardiogr 2007; 20: 270–275.

Douglas PS, O’Toole ML, Hiller WD, et al. Different effects of prolonged exercise on the right and left ventricles. J Am Coll Cardiol 1990; 15: 64–69.

Argiento P, Chesler N, Mulè M, et al. Exercise stress echocardiography for the study of the pulmonary circulation. Eur Respir J 2010; 35: 1273–1278.

Bidart CM, Abbas AE, Parish JM, et al. The noninvasive evaluation of exercise-induced changes in pulmonary artery pressure and pulmonary vascular resistance. J Am Soc Echocardiogr Off Publ Am Soc Echocardiogr 2007; 20: 270–275.

Ohuchi H. Cardiopulmonary response to exercise in patients with the Fontan circulation. Cardiol Young 2005; 15: 39–44.

Senzaki H, Masutani S, Ishido H, et al. Cardiac rest and reserve function in patients with Fontan circulation. J Am Coll Cardiol 2006; 47: 2528–2535.

Loomba RS, Danduran ME, Dixon JE, et al. Effect of Fontan fenestration on regional venous oxygen saturation during exercise: further insights into Fontan fenestration closure. Pediatr Cardiol 2014; 35: 514–520.

Knap K, Dłużniewska N, Tomkiewicz-Pająk L, et al. Cardiopulmonary exercise tests in rare cardiovascular diseases. J Rare Cardiovasc Dis 2015; 2: 139–143.

Tomkiewicz-Pajak L, Olszowska M, Komnata K, et al. Lung function and exercise tolerance in adults after Fontan procedure. Exp Clin Cardiol 2014; 20: 2606–2614.

Dimopoulos K, Okonko DO, Diller GP, et al. Abnormal ventilatory response to exercise in adults with congenital heart disease relates to cyanosis and predicts survival. Circulation 2006; 113: 2796–2802.

Tomkiewicz-Pająk L, Hoffman P, Trojnarska O, et al. Long-term follow-up in adult patients after Fontan operations. Pol J Cardio-Thorac Surg 2013; 4: 357–363.

Shafer KM, Garcia JA, Babb TG, et al. The importance of the muscle and ventilatory blood pumps during exercise in patients without a subpulmonary ventricle (Fontan operation). J Am Coll Cardiol 2012; 60: 2115–2121.

Khairy P, Poirier N, Mercier LA. Univentricular heart. Circulation 2007; 115: 800–812.

Takken T, Tacken MHP, Blank AC, et al. Exercise limitation in patients with Fontan circulation: a review. J Cardiovasc Med Hagerstown Md 2007; 8: 775–781.

Gewillig M, Brown SC, Eyskens B, et al. The Fontan circulation: who controls cardiac output? Interact Cardiovasc Thorac Surg 2010; 10: 428–433.

Fredriksen P, Therrien J, Veldtman G, et al. Lung function and aerobic capacity in adult patients following modified Fontan procedure. Heart 2001; 85: 295–299.

Buys R, Cornelissen V, Van De Bruaene A, et al. Measures of exercise capacity in adults with congenital heart disease. Int J Cardiol 2011; 153: 26–30.

Mezzani A, Giordano A, Moussa NB, et al. Hemodynamic, not ventilatory, inefficiency is associated with high VE/VCO2 slope in repaired, noncyanotic congenital heart disease. Int J Cardiol 2015; 191: 132–137.

Hawkins SMM, Taylor AL, Sillau SH, et al. Restrictive lung function in pediatric patients with structural congenital heart disease. J Thorac Cardiovasc Surg 2014; 148: 207–211.

Troutman WB, Barstow TJ, Galindo AJ, et al. Abnormal dynamic cardiorespiratory responses to exercise in pediatric patients after Fontan procedure. J Am Coll Cardiol 1998; 31: 668–673.

Varma C, Warr MR, Hendler AL, et al. Prevalence of “silent” pulmonary emboli in adults after the Fontan operation. J Am Coll Cardiol 2003; 41: 2252–2258.

Alonso-Gonzalez R, Borgia F, Diller GP, et al. Abnormal lung function in adults with congenital heart disease: prevalence, relation to cardiac anatomy, and association with survival. Circulation 2013; 127: 882–890.