Case Studies In Small Animal

Cardiovascular Medicine

Case 17

Two-dimensional echocardiograms

Right parasternal long-axis view

The left ventricular (LV) chamber is subjectively enlarged. The left atrium (LA) is probably similarly enlarged. The right ventricular (RV) chamber is normal.

Left apical four-chamber view

This view of all four chambers shows the same things as the previous view.

Video clip of a right parasternal short-axis view of the left ventricle from another dog with the same abnormality as "Chico."

The left ventricular chamber is subjectively much larger than normal in diastole. Having measured the end-systolic diameter, I can tell you that it is similarly enlarged, indicating that the left ventricular myocardium is failing. Because the end-diastolic and end-systolic diameters are increased similarly, the shortening fraction is normal. Since the left ventricle has grown larger (eccentric hypertrophy) and has a normal amount of contraction (i.e., shortening fraction, not contractility), it now pumps a larger quantity of blood with each beat than would a normal sized heart.

Right parasternal cross-sectional basilar view

The main pulmonary artery (PA) is wider than normal when compared to the diameter of the aorta (AO).

Right parasternal cross-sectional basilar view

The enlarged main pulmonary artery (PA) is again visualized next to the ascending aorta (AO). The short, fat arrow points to the descending aorta. The longer arrow points to a structure in between the aorta and pulmonary artery.

Quiz

Correct Quiz

©Mark D. Kittleson, D.V.M., Ph.D. All rights reserved.