Abstract 13004: Decreased Respiratory Variation of Hepatic Vein Doppler Predicts Major Clinical Outcomes in Fontan Patients
Introduction: Pulmonary blood flow in the Fontan circulation is dependent on respiratory effort due to the lack of a subpulmonic ventricle. Respiratory variation in hepatic vein (HV) flow measured by the Doppler has been described in Fontan patients as a surrogate of respiratory variation of pulmonary blood flow. Whether clinical outcomes are predicted by the degree of respiratory variation of the flow in Fontan patients is unknown.
Hypothesis: Reduced respiratory variation in forward HV flow is associated with adverse clinical outcomes.
Methods: We performed a retrospective review of 104 adult Fontan patients who had echocardiograms between 2004 and 2014. HV Doppler data included peak inspiratory and expiratory velocity time integral (VTI) of forward and retrograde flow during cardiac cycles in inspiration and expiration. The relationship between respiratory variation of HV Doppler measurements and major adverse events (death or transplantation) was examined using survival analysis.
Results: 104 post-Fontan patients (73% systemic LV, 42% atriopulmonary (APC) Fontan, mean age 28.4 ± 7.6 years, mean time from Fontan 21.7 ± 5.4 years) were analyzed. The mean difference between inspiratory and expiratory HV forward VTI was 8.4 ± 2.2cm and percent difference of HV forward VTI 61.9 ± 26.3%. 16 patients (5 APC, 11 lateral-tunnel) had HV forward VTI percent difference ≥ 90%, suggesting an inspiration-dependent venous flow independent of Fontan type (p = 0.69). 20 major adverse events occurred: 12 deaths, 8 transplants. After adjusting for potential confounders including body surface area, reduced respiratory variation in forward VTI was significantly associated with events: Compared to the middle tertile of difference in HV forward flow between inspiration and expiration, the lowest tertile had an estimated hazard ratio of 18.0 [95% CI 1.65-195.5, p=0.018] for adverse events.
Conclusions: Reduced respiratory variation in forward HV flow was predictive of death or transplantation in this cohort of Fontan patients. A subset (15%) had forward HV flow only during inspiration, independent of Fontan type. Additional studies are needed to establish further clinical significance and reproducibility of the HV Doppler parameters.
Author Disclosures: M. Mori: None. K. Shioda: None. M. Jokhadar: None. R.W. Elder: None. N. McCabe: None. C. Hebson: None. B.E. Kogon: None. A. Sahu: None. F. Rodriguez: None. M. McConnell: None. W.M. Book: Research Grant; Modest; CDC grant, PI.
- © 2014 by American Heart Association, Inc.