1. Department of Clinical Studies-Philadelphia; School of Veterinary Medicine; University of Pennsylvania; Philadelphia; PA
2. Mass Veterinary Cardiology Services Inc.; West Springfield; MA
3. Department of Clinical Studies; Ontario Veterinary College; University of Guelph; Guelph; ON; Canada
4. Department of Small Animal Clinical Sciences; College of Veterinary Medicine and Biomedical Sciences; Texas A&M University; College Station; TX