Author + information
Diastolic function (DF) is a strong predictor of exercise performance in patients with heart failure. We sought to identify echocardiographic (echo) parameters that correlate with peak oxygen consumption (peak VO2) and ventilatory efficiency (VE/VCO2 nadir) in patients with unexplained dyspnea.
Over 4 years, 464 patients underwent resting hemodynamic echo and simultaneous cardiopulmonary exercise testing with stress echo for the complaint of dyspnea.
|Variable||n||Mean VE/VCO2 Nadir||p value||Mean Peak VO2||p value|
|Grade I Diastolic||87||32.4||<0.001||16.7||<0.001|
|Grade 2–4 Diastolic||103||32.5||<0.001*||16||<0.001*|
|Left Atrial Volume Index <28||187||29.9||ref||20.0||ref|
|Left Atrial Volume Index >28||254||31.5||0.003||18.1||0.002|
|Rest E/e' <15||366||30.5||ref||19.6||ref|
|Rest E/e' >15||59||32.6||0.003||15.6||<0.001|
|Normal resting RVSP***||324||30.7||ref||19.4||ref|
|Elevated resting RVSP**||51||33.6||0.004||14.3||<0.001|
After correcting for age, gender, body mass index, beta blocker therapy, resting ejection fraction (EF), and peak stress EF, both DF grade (p=0.002) and estimated right ventricular systolic pressure (RVSP, p<0.001) remain independent predictors of peak VO2. When correcting for the same factors, RVSP (p<0.001) remains independently associated with VE/VCO2 but DF grade (p=0.11) does not.
Our data show that DF is associated with reduced peak VO2 in a cohort referred for dyspnea. VE/VCO2 correlates more closely with RVSP. Subjects with heart failure and preserved ejection fraction (HFpEF) are known to develop precapillary pulmonary hypertension late in the disease course, and peak pulmonary pressures have been shown to predict mortality in this cohort. Our data suggest that VE/VCO2 nadir could potentially identify those patients with HFpEF and significant pulmonary hypertension who are at increased risk of subsequent mortality, but this needs confirmation in a dedicated cohort of patients with HFpEF.
Oral Contributions West, Room 3006
Saturday, March 09, 2013, 9:00 a.m.-9:15 a.m.
Session Title: Novel Applications of Echocardiography: Implications for Clinical Use
Abstract Category: 18. Imaging: Echo
Presentation Number: 909-7
- 2013 American College of Cardiology Foundation