Heart disease can affect many dogs, but in some breeds early testing is critical. Genetics is part of the puzzle when it comes to canine health testing prior to breeding. A cardiac exam is an important physical (phenotype) health test for dogs. Responsible breeders aiming to produce healthy puppies will conduct cardiac testing on both parents prior to breeding where it is recommended for that breed.
Cardiac testing is one of the phenotypical evaluations that are registrable with the Orthopedic Foundation for Animals (OFA). Embark currently tests for 250+ genetic health conditions. Many of them are also registrable with the OFA.
Cardiac testing is important because it identifies both congenital (a malformation of the heart) and adult-onset heart disease that develops later in life. The OFA has two cardiac databases: the Basic Cardiac Database and the Advanced Cardiac Database. These tests determine if a dog is phenotypically normal. Dogs can be normal if they are without a cardiac murmur or if they have an “innocent heart murmur” that is otherwise normal during an echocardiographic examination and Doppler studies. Innocent murmurs can be related to normal blood flow in the circulation and are most common in young, growing dogs.
A veterinary cardiologist board-certified by the American College of Veterinary Internal Medicine performs the exams. Results from an exam using auscultation can be recorded in the OFA Basic Cardiac Database. Results from an exam using echocardiograms can be recorded in the OFA Advanced Cardiac Database. Cardiac murmurs can be listed as systolic, diastolic, or continuous. They can also be detected intermittently.
Basic Cardiac Database
This exam is based on auscultation, which is listening to the sounds of the heart using a stethoscope. Areas where the vet will listen include cardiac valves, the subaortic area, the ascending aorta, the pulmonary artery, and the craniodorsal cardia base. The left and right precordium should also be examined. Because heart disease can develop later in life, these exams are valid for one year.
Advanced Cardiac Database
This exam results in a two-tiered clearance for dogs. congenital cardiac disease and adult-onset cardiac disease. Since Oct. 1, 2020 this exam now requires echocardiographic exams to be included in the Advanced Cardiac Database. This exam uses two-dimensional, pulse-wave Doppler and continuous-wave Doppler.
Preliminary evaluation can be done for puppies at 8- to 10-weeks-old prior to placing puppies in new homes. Dogs must be at least 12-months-old or older to be included in the OFA databases.
Dogs are rated either phenotypically normal, or with abnormalities / murmurs graded from 1 (very soft murmur), 2 (soft murmur readily heard), 3 (moderately intense murmur), 4 (loud murmur), 5 (loud murmur with palpable precordial thrill), and 6 (loud murmur with palpable precordial thrill, and audible when stethoscope is lifted).
The Orthopedic Foundation of America is a leading canine health registry and public database. The OFA registry also takes results for hips and eyes. For more information on genetic health testing, Embark offers a search tool which lists all 250+ genetic health tests Embark offers.