Background: 2D strain imaging of the left atrium (LA) is a new echocardiographic method which allows us to determine contractile, conduit and reservoir functions separately. This method is particularly useful when changes are subtle and not easily determined by traditional parameters, as it is in arterial hypertension and atrial fibrillation (AF).
The aims of our study were: to determine LA contractile, conduit and reservoir function by 2D strain imaging in patients with mild arterial hypertension and paroxysmal AF; to assess LA contractile, conduit and reservoir functions' relation with LV diastolic dysfunction (DD) parameters.
Methods: LA contractile, conduit and reservoir functions together with echocardiographic signs of LV DD were assessed in 63 patients with arterial hypertension and paroxysmal AF. Patients were grouped according to number of signs showing LV DD (annular e' velocity: septal e' < 7 cm/s, lateral e' < 10 cm/s, average E/e' ratio > 14, LA volume index > 34 ml/m2, peak tricuspid regurgitation velocity > 2.8 m/s) present. Number of patients with 0 signs - 17, 1 sign - 26, 2 signs - 19. Contractile, conduit and reservoir functions were compared between the groups.
Results: Mean contractile, conduit and reservoir strains in all the patients were - 14.14 (± 5.83) %, 15.98 (± 4.85) % and 31.03 (± 7.64) % respectively. Contractile strain did not differ between the groups. Conduit strain was higher in patients with 0 signs compared with other groups (p = 0.016 vs 1 sign of LV DD and p = 0.001 vs 2 signs of LV DD). Reservoir strain was higher in patients with 0 signs compared with other groups (p = 0.014 vs 1 sign of LV DD and p < 0.001 vs 2 signs of LV DD).
Conclusions: The patients with paroxysmal AF and primary arterial hypertension have decreased reservoir, conduit and pump LA functions even in the absence of echocardiographic signs of LV DD. With increasing number of parameters showing LV DD, LA conduit and reservoir functions decrease while contractile does not change. LA conduit and reservoir functions decrease earlier than the diagnosis of LV DD can be established according to the guidelines in patients with primary arterial hypertension and AF.
Keywords: Arterial hypertension; Atrial fibrillation; Diastolic dysfunction; Left atrial strain.