Doppler echocardiographic effects of medetomidine on dynamic left ventricular outflow tract obstruction in cats.
OBJECTIVE
To evaluate the effects of medetomidine on dynamic left ventricular outflow tract (LVOT) obstruction in cats with left ventricular hypertrophy.


METHODS
Clinical trial.


METHODS
6 domestic shorthair cats with echocardiographic evidence of dynamic LVOT obstruction.


METHODS
Cats were restrained in lateral recumbency, and baseline M-mode and Doppler echocardiographic examinations were performed. An ECG was recorded continuously, and blood pressure was measured indirectly with Doppler instrumentation. Medetomidine (20 microg/kg 19.1 microg/lb]) was then administered i.m., and examinations were repeated 15 minutes later.


RESULTS
Significant decreases in heart rate, LVOT velocity, and the LVOT pressure gradient were documented following medetomidine administration. After adjusting for the effects of heart rate by ANCOVA, there were no significant differences in any other systolic or diastolic indices of left ventricular function.


CONCLUSIONS
Results suggest that administration of medetomidine to cats with dynamic LVOT obstruction may result in elimination of outflow tract obstruction; medetomidine may be a suitable sedative and analgesic agent in this subpopulation of cats.
Lamont
Leigh A
LA
Bulmer
Barret J
BJ
Sisson
David D
DD
Grimm
Kurt A
KA
Tranquilli
William J
WJ
D000818:Animals; D002371:Cat Diseases / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000503:physiopathology; D002415:Cats; D015150:Echocardiography, Doppler / Q000662:veterinary; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D017379:Hypertrophy, Left Ventricular / Q000150:complications / Q000662:veterinary; D006993:Hypnotics and Sedatives / Q000008:administration & dosage* / Q000494:pharmacology; D008297:Male; D020926:Medetomidine / Q000008:administration & dosage* / Q000494:pharmacology; D014655:Vascular Resistance / Q000187:drug effects; D014694:Ventricular Outflow Obstruction / Q000000981:diagnostic imaging / Q000188:drug therapy / Q000503:physiopathology / Q000662:veterinary*
D006993:Hypnotics and Sedatives; D020926:Medetomidine