Nick, an 11 year old Labrador/greyhound mix, came in to see me because his owner thought he had had a seizure a few days prior and now he was refusing to eat. Nick has a history of having seizures but they had been well controlled with anti-convulsant medication. In fact, it had been 5 years since they had witnessed any seizure activity at home. His owner had witnessed him collapse on the floor two days prior but he did not lose consciousness. It took him a few minutes to become normal again.
On examination, he was lethargic and did not want to stand up. His gum color was pale and brownish. He had lost 4 pounds since his last exam 6 months prior and he was about 5 pounds underweight. He had some dental tartar and a few skin lumps. His abdomen was soft and comfortable. His heart was difficult to hear with the stethoscope, almost muffled sounding which is abnormal given how thin he was.
After further questioning, it turns out that Nick had most likely not had a seizure but much more likely had actually fainted a few days ago. It can sometimes be hard to tell the difference in dogs. Using our in-house ultrasound unit, I quickly placed the probe on Nick's chest to assess his heart. What I found was fluid that was building up around his heart within the pericardium which is a sac that surrounds the heart and keeps it in the middle of the chest cavity. When fluid builds up in this space, it puts pressure on the heart muscle and limits the contractions of the heart. As more and more fluid builds up, the heart can actually become so compressed that it can no longer pump blood properly to the body. This is called pericardial effusion. There are two main causes of pericardial effusion. The first is a mass that develops on the base of the heart (right auricle) that goes on to rupture and leak blood into the sac. The second is called idiopathic, meaning we don't know what causes the leakage.
We then moved Nick to the xray table to radiograph his chest and abdomen looking for masses and other abnormalities. The xrays revealed that he had an enlarged liver, fluid in the pleural space (area around the lungs), and some arthritis in his back. No mass was found.
As luck would have it, our mobile radiology specialist, Dr. Jonathan Hayles, was at our clinic for another reason. He was able to use his expertise to remove the fluid from the heart sac by using the ultrasound as a guide. This life saving procedure takes teamwork as the patient must lay very still while the needle is guided into the correct location and the fluid is aspirated off. Nick had over 70mls of bloody fluid removed from his pericardium. Almost immediately, you could see his heart filling more normally, his gum color improve, and his energy come back.
The next step for Nick was a referral to the veterinary cardiologist to determine the primary cause of the effusion. He had an echocardiogram a few days later, which is a full ultrasound of his heart looking for masses or another cause for the fluid build up. Unfortunately, the cardiologist found a large mass on Nick's heart base. Due to the size and location of the mass, surgery was not an option. The owners elected humane euthanasia for Nick.
Even though this case turned out sad in the end, we thought it would be a good teaching example of an uncommon disease we see in dogs. We are so fortunate to live in a community with advanced veterinary medical care and specialists in many fields. Together we can provide the best care to our beloved pets during times of need.
Dr. Heather Kovacevich