Screening for Adult-Onset Heart Disease
Mission Valley Veterinary Cardiology offers cardiac screening services to dog breeders, registered breed clubs, and dog shows for the purposes of identifying inerited adult-onset heart disease in breeding animals. Arrangements can be made by contacting Dr. Richard Kienle at (408) 842-2899.
The screening examination includes a cardiovascular physical examination and a complete thoracic auscultation (listening to the chest with a stethoscope). Dogs with early or mild stages of adult-onset heart disease may have a completely normal physical examination. If the screening examination is normal, further diagnostic studies may be warranted to increase the level of confidence that the dog is normal. If the screening examination is abnormal, a tentative diagnosis may be made, but the definitive diagnosis requires other studies.
The standard electrocardiogram is used to assess the electrical activation of the heart. It consists of a 6 (minimum) lead recording and a 2 minute rhythm strip. Ventricular arrhythmias are common in dogs afflicted with DCM or inherited arrhythmias, however, the standard electrocardiogram may be normal in these dogs for several reasons. The frequency of ventricular arrhythmias are highly variable and may not occur during the short time of the evaluation. Also, not all dogs with DCM have ventricular arrhythmias. Likewise, the mere presence of a few ventricular premature beats does not constitute the diagnosis of DCM or inherited arrhythmias. The more complex and frequent the arrhythmia, the more likely that disease is present. In general, the ECG does not negate or preclude other diagnostic studies, it simply adds to the overall characterization of the disorder. In some situations, the results of the ECG may indicate a greater risk for sudden death in an individual patient.
Holter Monitor (24 Hr Ambulatory ECG)
The Holter monitor is a special digital ECG that is recorded for 24-48 hours . The recording is then evaluated off-line with the aide of specialized computer software. The advantage of the Holter monitor is that the ECG can be evaluated for a much longer period of time than the standard ECG making it more likely to detect abnormal events. Interpretation is similar to the standard ECG. There is evidence that suggests the results of Holter monitor alone may be used to detect early or occult DCM. A Holter examination is the gold-standard for providing a definitive diagnosis of inherited arrhythmias.
Ultrasound Examination (Echocardiography)
The ultrasound examination includes a complete anatomical, functional and Doppler evaluation of the heart and is intended to provide a definitive diagnosis of adult-onset heart disease. However, a normal echocardiogram only indicates that the dog does not have adult-onset heart disease at the time of the examination. The patient may still develop adult-onset heaert disease in the future. Also, subtle variations from normal may be difficult to discriminate from early or occult forms of disease.
Certification Classes (Results)
Normal: normal examination
Equivocal: adult-onset heart disease cannot be diagnosed nor excluded
Abnormal: examination indicative of adult-onset heart disease
Annual exams are recommended and are required for the ACVIM/OFA Advanced Cardiac Database.