Acute Right Ventricular Restrictive Physiology After Repair of Tetralogy of Fallot

Abstract

Background —Acute right ventricular (RV) restrictive physiology after tetralogy of Fallot repair results in low cardiac output and a prolonged stay in the intensive care unit (ICU). However, its mechanism remains uncertain. Methods and Results —In the first 24 hours after tetralogy of Fallot repair (n=11 patients), serial prospective measurements were performed of cardiac troponin T, indexes of NO production (NO 2 − and NO 3 − combined as NOx), and iron metabolism and antioxidants. RV diastolic function was assessed by transthoracic Doppler echocardiography. Patients who had a long stay in the ICU were characterized by restrictive RV physiology (nonrestrictive group [n=7]: 3.0±0.6 days [mean±SD]; restrictive group [n=4]: 10.7±3.1 days). Troponin T peak concentration and the area under its concentration-time curve (AUC) were higher in the restrictive RV group (peak: restrictive group 17.0±2.8 μg/L, nonrestrictive group 10.4±4.6 μg/L, P <0.03; AUC: restrictive group 268.8±73.6 μg · h −1 · L −1 , nonrestrictive group 136.2±48.3 μg · h −1 · L −1 , P <0.03). Plasma NOx/creatinine concentrations were higher in the restrictive group than the nonrestrictive group at 2 hours after bypass (restrictive group 1.3±0.4, nonrestrictive group 0.8±0.2; P =0.04) but were similar by 24 hours. Iron loading peaked 2 to 10 hours after bypass and was more severe in the restrictive group (peak transferrin saturation: restrictive group 83.9±13.0%, nonrestrictive group 58.3±16.2%, P =0.05; minimum total iron-binding capacity: restrictive group 0.59±0.21%, nonrestrictive group 0.76±0.06%, P =0.04; minimum iron-binding antioxidant activity to oxyorganic radicals: restrictive group 9.5±22.4%, nonrestrictive group 50.6±11.4%, P =0.01). Conclusions —After tetralogy of Fallot repair, acute restrictive RV physiology is associated with greater intraoperative myocardial injury and postoperative oxidative stress with severe iron loading of transferrin.

Right ventricular diastolic dysfunction in the postoperative period of tetralogy of Fallot

“…Even considering the significant surgical factors 3,4,6,11,12 for determining ventricular restriction, this study, like others [2][3][4][5][6][7][8][9] , could not demonstrate that relation.…”

“…Several studies have correlated preoperative and operative factors with restrictive right ventricular physiology; however, as in our study, few relevant data were found [1][2][3][4][5][6][7][8][9] . Restrictive right ventricular physiology may relate to a process of endomyocardial fibrosis intrinsic to the disease itself and intensified as time goes by 10 , to the ventriculotomy, and to the interposition of patches in the interventricular septum and in the infundibulum 3,4,6 .…”

“…Studies in the literature have shown that electrocardiographic, radiological, and clinical alterations may be related to the prognosis of the patient undergoing total repair of tetralogy of Fallot [1][2][3][4][5][6][7][8][9] . Biventricular systolic function is preserved in most patients [2][3][4] .…”

Prior Cardiac Surgery Is Independently Associated With Decreased Survival Following Infant Tracheostomy

“…For example, many often suffer concomitant neurologic and renal injuries during and after surgery related to exposure to cardiopulmonary bypass and postoperative hemodynamic instability. 15,16 As a result of all of the aforementioned co-morbidities, these patients likely have less reserve as compared with other patients and therefore are less likely to tolerate respiratory complications that may occur at home such as a mucus plug or dislodgment of their artificial airway. 17 The higher rate of home mechanical ventilation in patients with cardiac surgery, although not independently associated with mortality, does mandate a much higher level of care for many of these infants and should not be dismissed as a possible contributing factor.…”

Low Cardiac Output Due to Acute Right Ventricular dysfunction and Cardiopulmonary Interactions in Congenital Heart Disease (2013 Grover Conference Series)

“…18 However, its early manifestations are transient. Right ventricular compliance tends to improve postoperatively over the first 48-72 hours in most cases.…”