Abstract 16034: Affect of Warfarin on Long Term Pulmonary Arterial Hypertension (PAH) Mortality: Change of facts?
Introduction: PAH is a progressive disease with high mortality. Vascular changes in PAH like vasoconstriction, smooth muscle cell and endothelial proliferation, prothrombotic agents and cytokines are most likely explanation of thrombosis. Guidelines suggest keeping INR between 1.5-2.5 after the diagnosis of PAH. Data from earlier observational studies is mixed and did not take in account known prognostic factors of mortality in PAH like cardiac index (CI), right atrial pressure (RAP), pulmonary arterial pressure (PAP) and wide variety of newer medications for PAH. This study gives insight into the potential benefit of warfarin use by reducing long term PAH mortality and simultaneously looking at known poor prognostic factors and PAH medications.
Hypothesis: Warfarin reduces long term mortality in PAH.
Methods: Retrospective data is collected from 1996 to 2010. Cohort I, PAH patients on warfarin and Cohort II PAH patients not on warfarin. Inclusion criteria are; diagnosis of PAH, warfarin started within 90 days after PAH diagnosis and age >18 years. Studied variables are, age, gender, race, co-morbidities like diabetes, hypertension, PAH specific medications. Patients with heart or lung transplant are excluded. All cause mortality at 1,2,3,4 and 5 year is calculated for both cohorts.
Results: Cohort I (n=106) and Cohort II (n=234), mean age 62.0±15.93 vs 69.38±15.98 p<0.001, PASP 63.13±16.15 vs 63.6±16.4 p=NS, RAP 13.45±4.84 vs 13.48±5.04 p=NS and CI 2.84±1.08 vs 2.48±0.56 p=NS. Mortality at 1,2,3,4 and 5 year in Cohort I and II are 19.8% vs 29.5% p=0.06, 23.5% vs 17.6%p=0.261, 12.3% vs 16.9% p=0.39, 10.5% vs 15.0% p=0.416and 5.9% vs 3.1% p=0.42 respectively. All studied variables are equally distributed among both cohorts. Cohort I and II, 1 year mortality in Hispanics is 0% vs 45.7% p=0.003.
Conclusion: Our results show trend towards significant mortality reduction at 1 year in PAH patients on anticoagulation. Interesting finding is significantly lower mortality rate in Hispanics at 1 year which should be looked at in the future race specific PAH trials. In conclusion, Warfarin use did not show any mortality benefit over 5 years in PAH patients.
- © 2011 by American Heart Association, Inc.