Abstract 16619: Bendopnea, a Novel Symptom of Heart Failure, is Mediated via Elevated Left Ventricular Filling Pressures
Introduction: Many heart failure patients describe dyspnea when bending forward, such as when putting on their shoes or socks. The hemodynamic correlates of this symptom, which we have termed “bendopnea,” have not previously been characterized.
Methods: We conducted a prospective study of a convenience sample of 84 patients with systolic heart failure referred for right heart catheterization. Immediately prior to catheterization, subjects were tested for the presence and time to onset of bendopnea. A subset of the cohort (n=38) also had hemodynamics measured when sitting and bending. Cardiac output was measured by thermodilution. Wilcoxon rank-sum tests compared hemodynamics stratified by bendopnea status, and a mixed linear model with unstructured covariance and fixed effects for bendopnea status and position compared hemodynamics across position.
Results: Bendopnea was present in 24/84 (30%) subjects, with median (interquartile range) time to symptom onset of 8 (7, 11) seconds. Subjects with vs. without bendopnea had a higher supine right atrial pressure (RAP) [11 (7, 15) vs. 6 (3, 10) mmHg; p=0.001] and pulmonary capillary wedge pressure (PCWP) [24 (22, 26) vs. 18 (8, 23) mmHg; p=0.0003]. Cardiac index (CI) did not differ between these 2 groups [2.1 (1.8, 2.6) vs. 2.3 (2, 2.6), p=0.2]. In subjects with versus without bendopnea, there was a trend for a 2-fold increase in the prevalence (33% vs. 17%, p=0.09) of a supine hemodynamic profile consisting of a low RAP (<10 mm Hg) and a high PCWP (≥22 mm Hg), but no increase in the prevalence of a supine hemodynamic profile consisting of a high RAP and low PCWP (8% vs. 10%, p=1.0). The sitting PCWP was higher in subjects with vs. without bendopnea [26 (19, 28) mmHg vs. 14 (8, 22) mmHg; p=0.05]. During bending, both RAP and PCWP increased in both groups (p<0.0001 for all), but there was no difference in the amount of increase between the two groups (RAP: p=0.5; PCWP: p=0.7). The CI did not change with bending in either group (p=1.0).
Conclusion: Bendopnea is mediated via a further increase in left ventricular filling pressures during bending in subjects whose PCWP is already high. Physician awareness of this symptom should improve noninvasive assessment of hemodynamics in heart failure patients.
- © 2012 by American Heart Association, Inc.