Essential diagnostics in the exam room for cardiology (Proceedings)

Determine age, breed, and sex of the patient to help formulate a rule-out list and help to determine prognosis. Note current pre-existing diseases. Record current drugs and clinical response. Record presenting clinical signs and duration and progression of the illness.

Physical Examination

In addition to a complete physical examination, perform a thorough cardiovascular examination including all of the following

1. Auscultation, noting

A. Heart rate

B. Presence or absence of the following:

• Heart murmur (Point of maximum intensity, radiation, loudness, timing, character)

• Gallop sound (rhythm)

• Other abnormality heart sounds (e.g. splitting of S1 or S2, clicks, rubs)

• Arrhythmias

• Abnormal lung sounds

2. Femoral Pulse palpation (character, rate, rhythm, pulse deficits)

3. Jugular vein observation for distention or pulsation

4. Precordial palpation for apical impulse, presence of thrills

5. Abdominal palpation to assess organomegaly and detect ascites

Electronic Stethoscope

Electronic stethoscopes have improved dramatically in the past 10 years. This problem can be partially addressed by coupling the electronic stethoscope's chest piece to the chest wall with carefully applied ultrasound gel. In addition to electronic amplification of heart sounds and murmurs, most of the electronic stethoscopes currently allow the user to record and play back sounds at either normal or half speed, a useful feature for judging the timing and shape or quality of murmurs in tachycardic patients and for judging the timing of transient heart sounds such as clicks or gallops. Some models also provide the ability to record graphic representations of sounds in a digital file format (i.e., a phonocardiogram) that can be stored on a computer, possibly even becoming part of the patient's medical record. A new (2005) electronic stethoscope, the 3M Littmann model 4100, features useful ambient noise reduction circuitry that appears to overcome most if not all of the problems of background noise amplification that plagued previous models. This stethoscope has the additional advantage of allowing wireless (infrared) digital file transfer to a computer, although this system currently has no provision for recording a timing ECG.

Electrocardiography

It is recommended that practitioners have two ECG machines: an oscilloscope and an electrocardiograph. The electrocardiograph linked with a strip recorder or printer provides a permanent record. A PC based system is highly recommended. The ECG is required for the accurate diagnosis of arrhythmias and conduction disorders. Just some of the indications include arrhythmias heard on auscultation, breathing problems, shock, fainting or seizures, cardiac murmurs, and systemic disease that affect the heart (tumors, kidney function, heartworm disease, etc.). The ECG is also useful as part of the preoperative work-up in older animals, for monitoring patients during and after surgery, and for evaluating the effects of cardiac drugs.

Blood Pressure

On a practical level, every veterinary practice should have a blood pressure unit, especially in feline medicine. Numerous studies in the veterinary literature show that a large percentage of cats more than 12 years of age have hypertension, either secondary to chronic renal disease or from underlying thyroid disease. A blood pressure monitoring device is critical for practitioners who see a large number of geriatric feline patients. Blood pressure should be recorded for cats with left ventricular hypertrophy of an unknown cause, cats with renal disease, cats with acute visual problems, and other critically ill patients.

References

Smith, F.W.K., Keene, B., & Tilley, L.P.: Rapid Interpretation of Heart Sounds, Murmurs, Arrhythmias, and Lung Sounds: A Guide to Cardiac Auscultation in Dogs and Cats. CD-ROM and 90 pp. manual. Elsevier. 2nd Edition. St Louis, 2007.

Tilley, L.P., and Smith, F.W.K. (Eds): The Five Minute Veterinary Consult-Canine & Feline Medicine 4th Edition. Ames, Iowa, Wiley Blackwell Publishing, 2008.

Tilley, L.P., Smith, F.W.K., Oyama, M., and Sleeper, M.: Manual of Canine & Feline Cardiology, 4th Edition.Elsevier, St. Louis, 2008.

Kittleson, M.D., Kienle, R.D.: Small Animal Cardiovascular Medicine. Philadelphia, Mosby, 1998.

Norsworthy, G., Crystal, M., Fooshee, S., Tilley, L.P.: The Feline Patient, 3rd Edition. Ames, Iowa, Wiley Blackwell Publishing, 2006.