Diastolic heart function in Dobermans with dilated cardiomyopathy

Abstract

BACKGROUND: Assessment of diastolic function in patients with dilated cardiomyopathy (DCM) has the potential to add valuable information regarding hemodynamics, disease severity, and prognosis. The purpose of this study was to determine transmitral flow (TMF), isovolumic relaxation time (IVRT), pulmonary venous flow (PVF), flow propagation velocity (Vp), and mitral annular velocities by tissue Doppler in Doberman Pinschers with and without DCM. HYPOTHESIS: It was anticipated that normal and DCM Dobermans would differ with respect to these parameters, and that associations with time to congestive heart failure (CHF) or death would be found. ANIMALS: Thirty client-owned Doberman Pinschers (10 each of normal, occult DCM, and overt DCM) were studied. METHODS: Each dog underwent echocardiography with or without thoracic radiography (to confirm CHF) for classification as normal or DCM-affected, followed by collection of echocardiographic diastolic parameters. RESULTS: The group with occult DCM exhibited features of pseudonormal TMF, reduced systolic to diastolic PVF ratio, and reduced Vp. Shorter early TMF deceleration time (DTE) was associated with shorter time to CHF or sudden death. The group with overt DCM exhibited restrictive TMF, blunted systolic PVF, and reduced early and late diastolic mitral annular velocities. CONCLUSIONS AND CLINICAL IMPORTANCE: Doberman Pinschers showed evidence of moderate and severe diastolic dysfunction in occult and overt DCM, respectively. Short DTE may be a useful predictor of onset of CHF or sudden death.