Effect of Pimobendan or Benazep ril H ydrochloride o n S urvival Times in D ogs with Congestive H eart F ailure C aused b y Naturally Occurring M yxomatous M itral Valve D isease: T he Q UEST S tudy

pimobendan, 140 days for benazepril hazard ratio 5 0.688, 95% confidence limits [CL] 5 0.516–0.916, P 5 .0099). The benefit of pimobendan persisted after adjusting for all baseline variables. A longer time to reach the endpoint was also associated with being a Cavalier King Charles Spaniel, requiring a lower furosemide dose, and having a higher creatinine concentration. Increases in several indicators of cardiac enlargement (left atrial to aortic root ratio, vertebral heart scale, and percentage increase in left ventricular internal diameter in systole) were associated with a shorter time to endpoint, as was a worse tolerance for exercise.