Heartworm disease, echocardiogram, 4-chamber view, dog

Echocardiogram showing the 4 cardiac chambers in a 10-year-old pit bull-type dog with pigmenturia, anemia, and clinical signs of low-output heart failure. A cluster of heartworms is visible within the right atrium and ventricle. The echogenic cuticles of the worms create hyperechoic parallel lines that look like long, bright equal signs (*). The right atrium and ventricle are dilated. The left ventricle is relatively underloaded. LA, left atrium; LV, left ventricle; MV, mitral valve; RA, right atrium, RV, right ventricle; TV, tricuspid valve.