This video shows a massive clump of heartworms entangled around the tricuspid valve in the heart. The heartworms appear as two small, mobile, parallel lines in the top part of the video within the right ventricle and right atrium. The increased right-sided pressures are flattening the septum between the left and right ventricles, causing decreased left ventricular filling and decreased forward cardiac output to the systemic circulation. Treatment is emergency heartworm removal via cardiac catheterization and supportive care. Unfortunately, the mortality rate of this condition is high.
Another reason why I always say YES when asked if ultrasound might be helpful for a case. Some types of kidney stones don't show up on x-rays. This 3 year old Yorkie Terrier had a low platelet count and lab work changes suggestive of a congenital liver shunt. Ultrasound confirmed a small liver shunt. A stone obstructing the right ureter was also identified. I've never passed a kidney stone but I know this must have been super painful!