Ventricular dyssynchrony predicts mortality in severe aortic stenosis

In his PhD thesis, Lars Gunnar Klæboe has used specle-tracking echocardiography to gain insights on cardiac function and dyssynchrony in aortic stenosis.


MAIN RESULTS:

  1. Mechanical dispersion predicts prognosis in aortic stenosis.

  2. Few patients with left bundle branch block following TAVI have classical mechanical dyssynchrony.

THESIS DEFENCE:

Thesis: Strain imaging in aortic stenosis
Candidate: Lars Gunnar Klæboe
Time: December 19, 2019 at 13:15
Place: Oslo University Hospital, Rikshospitalet B: Blått auditorium
Link to university website


SUMMARY:

(1) More pronounced mechanical dispersion and worse global longitudinal strain predict early death in severe aortic stenosis. The results were similar in surgically treated patients, those who underwent transcatheter aortic valve implantation (TAVI), and in medically treated patients.

The study includes strain echocardiography of 162 patients, of which 37 died during a median follow-up period of three years. Adding mechanical dispersion to other echocardiographic parameters (left ventricular ejection fraction, global longitudinal strain and valvulo-arterial impedance) improved correct classification of survivors and non-survivors.

(2) 25 % of older patients with severe aortic stenosis and normal QRS at baseline got left bundle branch block following TAVI. 93 % of them had homogenous ventricular contractions. Thus, classical mechanical dyssynchrony is rare in patients with TAVI-induced left bundle branch block.

140 patients with a mean age of 83 years were included in the study. All of them improved global longitudinal strain following the procedure. The mortality over the next 19 months was not increased in the group with new-onset left bundle branch block.

(3) Myocardial dyssynchrony improves following TAVI in patients with unchanged ventricular conduction.

REFERENCES:

(1) Klaeboe, L. G., Haland, T. F., Leren, I. S., ter Bekke, R. M., Brekke, P. H., Røsjø, H., Omland, T., Gullestad, L, Aakhus, S., Haugaa, K. H., & Edvardsen, T. (2017). Prognostic value of left ventricular deformation parameters in patients with severe aortic stenosis: a pilot study of the usefulness of strain echocardiography. Journal of the American Society of Echocardiography30(8), 727-735.

(2) Klaeboe, L. G., Brekke, P. H., Lie, Ø. H., Aaberge, L., Haugaa, K. H., & Edvardsen, T. (2018). Classical mechanical dyssynchrony is rare in transcatheter aortic valve implantation-induced left bundle branch blockEuropean Heart Journal-Cardiovascular Imaging20(3), 271-278.