An Increase in the Left Atrium Volume During Exercise is Associated With a Positive Result of a Diastolic Stress Test in Patients With Arterial Hypertension

Abstract

Aim. To study the relationship between changes in left atrial volume (LAV) during exercise and the result of a diastolic stress test (DST) in patients with arterial hypertension (AH).Material and methods. The study included 219 patients with AH without ischemic heart disease and atrial fibrillation. During the DST performed before and after exercise, the ratio of transmitral flow velocity to mitral annular velocity (E/e’), the left atrial global longitudinal strain in the reservoir phase (reservoir strain), and LAV were determined. The criterion for a positive DST was an increase in E/e′ ≥15.Results. A positive result of DST was observed in 90 (41.1%) patients. Patients with positive DST were older (65.0 and 59.0 years); among them, there were fewer men (24.4 and 41.1%), but more patients with obesity (66.7 and 40.3%) and diabetes mellitus (36.7 and 8.5%). At rest, patients with positive DST had higher E/e' ratio (11.5 and 8.8), pulmonary artery systolic pressure (29.0 and 27.0 mm Hg), and LAV (60.0 and 52.0 ml), but a lower left atrial reservoir strain (20.0 and 24.0%). During exercise in patients with positive and negative DST, E/e’ increased by 5.46 and 0.47 units, respectively. Changes in the LAV and reservoir strain during exercise in these groups were directed differently. In patients with positive DST, the left atrial reservoir strain decreased by 1.0 percentage points (pp) whereas in patients with negative DST, it increased by 8.0 pp. During exercise, the LAV increased by 10.0 ml in patients with a positive DST, whereas in the alternative group, the LAV decreased by 8.5 ml. The AUC for changes in LAV as an indicator of a positive DST was 0.987 while the AUC for the resting left atrial reservoir strain was 0.938. An increase in LAV >1 ml, as an indicator of a positive DST has a sensitivity of 96.9% and a specificity of 95.1%.Conclusion. In AH patients, changes in left ventricular filling pressure are associated with a unidirectional change in LAV. An increase in LAV during exercise by more than 1 ml can serve as a criterion for a positive DST result. This assessment was consistent with the assessment of the DST result by the E/e’ criterion >15 in 94.5% of cases.