Breed Predispositions for Congenital Heart Defects Defect:  Patent ductus arteriosus Breeds:  Toy and miniature poodles, German shepherd, collie, Pomeranian, Shetland sheep dog, Maltese, English Springer spaniel, Keeshond, Yorkshire terrier, American cocker spaniel, Rottweiler Defect:  Subaortic stenosis Breeds:Newfoundland, Rottweiler, Golden retriever, Boxer Defect: Pulmonic stenosis Breeds:  English bulldog, Terrier, Beagle, Mastiff, Samoyed, Miniature schnauzer, American cocker spaniel, Keeshond, West Highland white terrier Defect: Ventricular septal defect Breeds: English springer spaniel Defect: Tetralogy of Fallot Breeds:Keeshond Defect: Mitral valve dysplasia Breeds:  Rottweiler; large breeds Defect: Tricuspid valve dysplasia Breeds: Labrador retriever; large breeds (>20 kg) Defect:  Persistent right aortic arch Breeds:German shepherd, Irish setter For information on specific abnormalities, please click Veterinary Partner