Physician Update: AHA Special Edition
Read more articles from our most relevant research presented at the 2020 AHA Scientific Sessions.
Clinical Heart and Vascular Center
The E/e’ ratio has become the foundation of echocardiographic assessment of left ventricular diastolic function. Many clinicians and researchers use E/e’ as a surrogate measurement of left ventricular filling pressure in patients with and without known cardiovascular disease. These conclusions are based primarily on cross-sectional data, and prior studies have raised concerns that E/e’ does not actually “measure” LV filling pressure.
The goal of our study, presented virtually at #AHA20, was to determine if E/e’ changed in parallel when LV filling pressure was altered experimentally in healthy, sedentary middle-aged adults. We used lower body negative pressure and rapid saline infusion to decrease and increase cardiac venous return, respectively. Using echocardiography and right heart catheterization, we measured E/e’ and pulmonary capillary wedge pressure (PCWP) simultaneously and performed a linear regression for each subject.
“Our study highlights the limitations of using E/e’ as a measure of LV filling pressure, particularly in healthy adults. While E/e’ may be associated with PCWP in large groups of individuals, it is impossible for clinicians to know if E/e’ is useful in their individual patient.”
As a group, E/e’ was modestly associated with PCWP. Yet only 31% had a close correlation between E/e’ and PCWP. No subject had a 1:1 relationship between E/e’ and PCWP. Further, invasively measured LV compliance, LV relaxation, and baseline LV filling pressure did not predict whether a subject had a close relationship between E/e’ and PCWP. Our study highlights the limitations of using E/e’ as a measure of LV filling pressure, particularly in healthy adults. While E/e’ may be associated with PCWP in large groups of individuals, it is impossible for clinicians to know if E/e’ is useful in their individual patient. Therefore, we believe E/e’ may be a good marker of cardiac disease but should not be considered a “measurement” of LV filling pressure in clinical practice.