Abstract 15611: Altitude is Not a Risk Factor for Patients Undergoing Bidirectional Cavopulmonary Anastomoses and Fontan Operation: A Comparative Study Between Denver, Edmonton and Toronto
Objectives: Outcomes of patients with single ventricle physiology undergoing cavopulmonary palliation depend on low pulmonary vascular resistance (PVR), and therefore have been suggested to be adversely impacted by living at higher altitude. We compared hemodynamic variables and correlated them to the post-operative outcomes from 3 centers (Denver, Edmonton and Toronto) at different altitudes.
Results: Hemodynamic data at pre-bidirectional cavopulmonary anastomoses (BCPA) and pre-Fontan catheterization were collected from the 3 centers. VO2 was calculated using Lindahl's equation. There were 115 patients from Denver (altitude 1600±310m, highest 2572m) undergoing BCPA with 3 deaths and 8 heart transplantations (HTx), and 103 patients undergoing Fontan with 3 HTx. There were 96 patients from Edmonton (altitude 626±290m, highest 1176m) undergoing BCPA with 1 death and 2 HTx, and 79 undergoing Fontan with 3 HTx. There were 266 patients from Toronto (altitude 195±88m, highest 493m) undergoing BCPA with 16 deaths and 7 HTx, and 190 undergoing Fontan with 13 deaths. There was no significant difference in BCPA and Fontan failure defined as death and HTx among the 3 centers (p>0.60). Freedom from BCPA failure at 5 years was 88%, 92% and 87% in Denver, Edmonton and Toronto, respectively. Pre-BCPA patients from Edmonton had higher PVR (2.97±1.9 Wood U·m2) vs. Denver (2.50±1.8 Wood U·m2, p<0.0001) and vs. Toronto (2.51±1.3 Wood U·m2, p=0.003).Pre-Fontan PVR was higher in patients from Edmonton (2.43±1.4 Wood U·m2) vs. Toronto (1.9±1.0 Wood U·m2, p=0.003), but no difference in pulmonary artery pressure (PAP) or trans-pulmonary gradient (TPG) between the 3 centers (p>0.15 for all) was noted. Patients from the 3 centers were analyzed together and no significant correlation between altitude and PVR, PAP or TPG (p>0.20) was found. BCPA failure was positively correlated with higher PVR (p=0.02) and the presence of right ventricle as the systemic ventricle (p=0.046). Fontan failure was positively correlated with higher PAP (p=0.03) and TPG (p=0.06).
Conclusions: Patients from the 3 centers have favorable outcomes after BCPA and Fontan procedure. The risk factors for palliation failure are elevated PVR, PAP and TPG and a systemic right ventricle, but not altitude.
- © 2010 by American Heart Association, Inc.