[Mitral valve dysplasia in a cat causing reversible left ventricular hypertrophy and dynamic outflow tract obstruction].

Abstract

A 6-month-old male European shorthair cat was examined because of a 2/6 systolic left apical cardiac murmur. Echocardiography revealed severe concentric left ventricular hypertrophy and severe dynamic left ventricular outflow tract obstruction (pressure gradient of 85 mmHg) caused by systolic anterior motion (SAM) of the septal mitral valve leaflet. After 2 months of oral treatment with atenolol, the cardiac murmur had disappeared. Echocardiography showed only slight thickening of the interventricular septum and resolution of the pressure gradient. The cat was discharged and its owner was advised to continue atenolol lifelong. Echocardiographic findings of a combination of left ventricular concentric hypertrophy and dynamic left ventricular outflow tract obstruction can be caused by hypertrophic obstructive cardiomyopathy (HOCM) or mitral valve dysplasia in the absence of hypertension and fixed aortic stenosis. In the case of HOCM, left ventricular hypertrophy is the primary process. In the case of mitral valve dysplasia, systolic anterior motion of the mitral valve is the primary problem, which leads to dynamic left ventricular outflow tract obstruction and ultimately to left ventricular concentric hypertrophy, due to pressure overload. If the left ventricular outflow tract obstruction is reduced with an oral beta-receptor blocker the secondary left ventricular hypertrophy may resolve. This would not happen in the case of hypertrophic obstructive cardiomyopathy. To the best of the authors' knowledge, this is the first documented case of severe dynamic left ventricular outflow tract obstruction and severe left ventricular hypertrophy in a cat successfully treated with oral atenolol.

• Authors: N W Kuijpers, V Szatmári
• Journal: Tijdschrift voor diergeneeskunde (Tijdschr Diergeneeskd) Vol. 136 Issue 5 Pg. 326-31 (May 01 2011) ISSN: 0040-7453 [Print] Netherlands
• Vernacular Title: Mitraalklepdysplasie als oorzaak voor een reversibele hypertrofie en dynamische uitstroombaanobstructie van de linker ventrikel bij een kat.
• PMID: 21614848 (Publication Type: Case Reports, English Abstract, Journal Article)

Chemical References

• Adrenergic beta-1 Receptor Antagonists
• Atenolol

Topics

• Adrenergic beta-1 Receptor Antagonists (therapeutic use)
• Animals
• Atenolol (therapeutic use)
• Cat Diseases (diagnosis, drug therapy)
• Cats
• Echocardiography (veterinary)
• Heart Valve Diseases (complications, diagnosis, drug therapy, veterinary)
• Hypertrophy, Left Ventricular (diagnosis, drug therapy, etiology, veterinary)
• Male
• Mitral Valve (pathology)
• Treatment Outcome
• Ventricular Outflow Obstruction (diagnosis, drug therapy, etiology, veterinary)