Conference: 2012 International PHA Conference and Scientific Sessions
Release Date: 06.22.2012
Presentation Type: Abstracts
Fenstad E1, Le R2, McGoon M1, Munger T1, Frantz R1, and Kane G1.
Division of Cardiovascular Diseases1, Department of Internal Medicine2, Mayo Clinic, Rochester, MN, USA.
BACKGROUND: Electrocardiographic findings in patients with pulmonary arterial hypertension (PAH) have been described previously in a small subset of patients with Scleroderma. However, in patients with PAH the prognostic significance of these findings remains unknown.
METHODS: Single center study of consecutive patients diagnosed with PAH at a specialty Pulmonary Hypertension center between 1995-2005 (N=422). Mortality was censored at transplant or at 5 years. Twelve lead electrocardiograms were reviewed by a single investigator blinded to outcomes. Definition of Right atrial enlargement (RAE) and right ventricular hypertrophy (RVH) utilized composite criteria.
RESULTS: Average heart rate was 82 ± 15 bpm. The majority of patients (55%) had idiopathic PAH and 73% were WHO functional class III-IV. Right and LBBB as well as intraventricular conduction delay were uncommon, 6.2%, 0.7%, and 4% respectively, yet 145 patients (34%) met criteria for incomplete RBBB. Incomplete and complete bundle branch block were not associated with adverse outcome. However, when characterized by PAH etiology, patients with idiopathic PAH and QRS < 104 ms (75th interquartile) had a survival benefit. Right atrial enlargement was evident in 176 (52%) patients while 328 (78%) patients had evidence of RVH. P wave amplitude was not related to outcome. Presence of tachycardia, RAE, or RVH on electrocardiogram predicted right heart catheterization characteristics of poor prognosis (higher right atrial pressure, lower cardiac index, & higher pulmonary vascular resistance). Adjusted for age & sex, tachycardia (Hazard ratio 1.70; 95% CI 1.17, 2.40), RAE (HR 1.47; 95% CI 1.11, 1.94) and RVH (HR 1.95; 95% CI 1.37, 2.86) were associated with five year mortality. These parameters remained predictive of death when also adjusted for age, sex and functional class [tachycardia (HR 1.59; 95% CI 1.09, 2.25), RAE (HR 1.41; 95% CI 1.07, 1.86) and RVH (HR 1.81; 95% CI 1.27, 2.65)].
CONCLUSIONS: These simple, prevalent, and easily obtainable findings on the index electrocardiogram predict outcome. Prolonged QRS was uncommon and not associated with outcome in this cohort.