Abstract 19958: Occult Left Atrial Dysfunction in Severe Pulmonary Arterial Hypertension: A Novel Application of Left Atrial Strain
Background: Evidence of left ventricular (LV) systolic dysfunction in severe pulmonary arterial hypertension (PAH) has been reported. We sought to determine the presence of left atrial (LA) dysfunction as a marker of impaired LV diastolic dysfunction (DD) in PAH.
Methods: Echocardiograms of 126 severe PAH subjects with normal LV function (EF>55%) and 75 controls were analyzed. Basic demographic data and mortality outcomes were obtained by chart review. Echocardiographic analysis included mitral and tricuspid regurgitation (MR, TR) severity, and standard Doppler parameters for DD using the 2016 recommendations. 2D speckle tracking software (Epsilon Imaging) was used for LA volume and LA longitudinal strain (LS) measurements. LA phasic function was calculated from LA volume curves.
Results: PAH patients demonstrated DD when compared to controls. (Figure) PAH patients had significantly lower peak LA LS (20 ± 8% vs. 35 ± 9, p-value <0.01), without significant differences in LA volume or MR severity. Furthermore, non-survivors with PAH showed significantly greater reductions in peak LA LS when compared to survivors. Moreover, analysis of phasic LA function demonstrated a reduction in LA booster pump function in non-survivors, supporting the presence of LA dysfunction. When guideline-directed diastolic categorization was performed, 39 patients (31%) demonstrated normal diastolic function, while 29 (23%) patients had abnormal diastolic function. Interestingly, the “indeterminate” classification was assigned to 58 (46%) of PAH patients.
Conclusions: Our results demonstrate left-heart DD is present in severe PAH. This dysfunction manifests as reduced LA strain and alterations in LA booster pump function, both associated with higher mortality. Paradoxically, these changes occur in the absence of LA enlargement, preventing definitive diagnosis of diastolic dysfunction using the current guidelines. These results suggest potential for LA strain as an adjunctive measure of diastolic function in severe PAH patients.
Author Disclosures: A. Singh: None. K. Kishiki: None. V. Mor-Avi: None. F. Maffessanti: None. M. Gomberg-Maitland: None. R.M. Lang: None. K. Addetia: None.
- © 2016 by American Heart Association, Inc.