Tissue Doppler and strain imaging in dogs with myxomatous mitral valve disease in different stages of congestive heart failure.
BACKGROUND
Tissue Doppler imaging (TDI) including strain and strain rate (SR) assess systolic and diastolic myocardial function.


OBJECTIVE
TDI, strain, and SR variables of the left ventricle (LV) and the interventricular septum (IVS) differ significantly between dogs with myxomatous mitral valve disease (MMVD) with and without congestive heart failure (CHF).


METHODS
Sixty-one dogs with MMVD with and without CHF. Ten healthy control dogs.


METHODS
Prospective observational study.


RESULTS
Radial motion: None of the systolic variables were altered and 3 of the diastolic velocities were significantly increased in dogs with CHF compared with dogs without CHF and control dogs. Longitudinal motion: 2 systolic velocities and 3 diastolic velocities were significantly increased in dogs with CHF compared with dogs without CHF and control dogs. Difference in systolic velocity time-to-peak between LV and IVS was significantly increased in dogs with MMVD with and without CHF compared with control dogs. In total, 11 (23%) of 48 TDI and strain variables differed significantly between groups. Left atrial to aortic ratio was positively correlated to early diastolic velocities, percentage increase in left ventricular internal diameter in systole was positively correlated to systolic and diastolic velocities, and mitral E wave to peak early diastolic velocity in the LV basal segment (E/Em) was positively correlated to radial strain and SR.


CONCLUSIONS
Few TDI and strain variables were changed in dogs with MMVD with and without CHF. Intraventricular dyssynchrony may be an early sign of MMVD or may be an age-related finding.
Tidholm
A
A
Albano Animal Hospital, Rinkebyvägen 23, Danderyd, Sweden. anna.tidholm@gmail.com
Ljungvall
I
I
Höglund
K
K
Westling
A B
AB
Häggström
J
J
D000818:Animals; D001783:Blood Flow Velocity; D004283:Dog Diseases / Q000473:pathology*; D004285:Dogs; D015150:Echocardiography, Doppler / Q000379:methods / Q000662:veterinary*; D006333:Heart Failure / Q000145:classification / Q000473:pathology / Q000662:veterinary*; D008943:Mitral Valve / Q000000981:diagnostic imaging; D008944:Mitral Valve Insufficiency / Q000473:pathology / Q000662:veterinary*