2016 ACVIM Forum Research Abstract Program

Kensuke Nakamura, Tatsuyuki Osuga, Tomoya Morita, Keitaro Morishita, Noboru Sasaki, Hiroshi Ohta, Mitsuyoshi Takiguchi. Hokkaido University, Sapporo, Japan Echocardiographic assessment of the severity of tricuspid regurgitation (TR) is less reliable compared to mitral regurgitation due to the complicated geometry and function of right ventricle. Spectral Doppler of hepatic veins (SDHV) has emerged as a useful examination to evaluate the severity of TR in humans. The hepatic vein blood flow waveform is multiphasic and typically consisted with four peaks. A small retrograde a-wave occurring after the Pwave of the electrocardiographic is created by retrograde blood flow during atrial contraction. A large anterograde S-wave occurring immediately after the QRX complex is created by blood flow toward the heart during ventricular systole. A small retrograde vwave occurs after ventricular systole. A large anterograde D-wave occurring after T-wave is created by ventricular diastole. The objective of the present study was to investigate the correlation between the presence of ascites and the findings of SDHV in dogs with TR. This is a clinical cohort study including twenty-seven client-owned dogs with TR. Dogs were divided into two groups based on the presence of ascites. Physical examination, SDHV and echocardiographic variables were compared between the groups. For the assessment of the comparative accuracy in identifying patients with ascites, receiver operating characteristic (ROC) curves was used. Peak velocity of v-wave and D-wave in dogs with ascites (n = 11) was significantly higher than dogs without ascites (n = 16). The highest accuracy was obtained for v-wave, with an area under the ROC curve (AUC) of 0.99, followed by D-wave, with an AUC of 0.95; late diastolic velocity of the septal mitral annulus (Am), with an AUC of 0.907. TR peak velocity had no significant difference between two groups. In conclusion, v-wave and D-wave obtained by SDHV has strong correlation with the presence of ascites in dogs with TR. Event monitors are a useful diagnostic tool for evaluating patients with episodic cardiac events. The ideal event monitor for use in veterinary practice would be non-invasive, affordable, accurate and reusable. Such devices are becoming increasing difficult to obtain. This study aimed to prospectively evaluate the feasibility of using the Medtronic Reveal LINQTM human implantable cardiac monitor (ICM) for cutaneous event monitoring for up to 5 days in 14 clinically healthy canines (21.5 kg, range 13.4-31.2 kg; 4.5 years range 1.5-13 years old) and two canines with reported collapse episodes (4.7 and 6.4 kg, 2.5 and 11 years old). The study consisted of developing a method to secure the low-profile device without causing discomfort at the location generating the strongest signal, adjusting the auto activation parameters, activating the device manually, and assessing the recordings for accuracy.