Abstract 711: Atrial Strain by Speckle Tracking Echocardiography: A New Non-Invasive Marker of Left Atrial Mean Pressure
Background: Better non-invasive markers of left ventricular (LV) end-diastolic pressure (EDP) are needed. Due to the curvilinear shape of the atrial pressure-volume relationship, atrial chamber compliance will decrease when atrial pressure is elevated. Therefore, we predicted that markedly elevated atrial pressures would be associated with reduced atrial strain, and that atrial strain would be inversely related to left atrial (LA) pressure. This hypothesis was tested in patients with congestive heart failure.
Methods: In 19 patients with idiopathic dilated cardiomyopathy, mean pulmonary capillary wedge pressure (PCWP) was measured invasively and was used as a surrogate for mean LA pressure. Using conventional 4-chamber recordings, LA strain was measured by speckle tracking echocardiography (STE) (Figure 1⇓) and LA area by planimetry.
Results: Mean PCWP was 18.5±7.3 mmHg, LA strain at maximum filling was 14.7±6.6% and LA area was 8.4±1.9 cm2/m2. There was a strong correlation between PCWP and peak LA strain (r = 0.85, p < 0.0001, Figure 1⇓), while the correlation between LA area and PCWP was not statistically significant (r = 0.41, p = 0.07).
Conclusion: We have demonstrated a close, inverse relationship between left atrial strain and left atrial pressure. These results suggest that assessment of atrial strain might be a useful supplementary clinical tool for non-invasive estimation of left atrial and LV end-diastolic pressures.