Abstract 12220: Intracavitary Left Ventricular Flow During Isovolumic Relaxation: Prevalence, Mechanism and Clinical Outcomes

Abstract

Introduction: Intracavitary flow (IVF) from LV base to apex during isovolumic relaxation (IVR) has been identified in patients with Grade I diastolic dysfunction (G1DD) associated with impaired relaxation. We examined the prevalence, mechanism, and outcomes of this phenomenon. Methods: Echocardiograms and medical records of 113 patients who met ASE criteria for G1DD without other cardiac abnormalities were reviewed. IVR was from relaxation onset to mitral opening. IVF was an apically directed signal with a defined envelope recorded by CW Doppler during IVR (Figure) confirmed by color Doppler. Global longitudinal strain was obtained in standard fashion using commercial equipment and analyzed for apical and basal segments. Results: IVF during IVR was present in 35 patients, absent in 27, and had inconclusive signals not meeting criteria in 51. The magnitude of reduction in apical strain was significantly larger in IVF patients than those without (-14% vs -5%, p = 0.04). This difference was present in both the lateral (-18% vs -7%, p = 0.04) and septal (-11% vs -1%, p = 0.05) segments. The rate of reduction in apical strain was also higher in the IVF group (0.318 strain fractions/sec vs 0.168, p = 0.03). No significant differences between groups existed for proportion of apical relaxation, change in strain between apex/base, proportion/magnitude/rate in basal strain. Patients with IVF during IVR had a non-significant trend for a higher death rate (23 vs 11%). There was no significant difference in hospitalization, heart failure, atrial fibrillation, CAD, or stroke. Conclusions: Apical intracavitary flow during IVR occurred in 31% of G1DD patients. Although mechanism is not fully defined, our data indicates that IVF during IVR is related to the magnitude and rate of apical relaxation. IVF during IVR may be of value in stratifying future risk in Grade I diastolic dysfunction patients but will require larger studies.