From death’s doorstep to a normal life span, Gus, a Boxer (the four-legged kind), now one-and-a-half years old, is alive today thanks to professional collaboration and owner commitment stretching from Philadelphia to Cincinnati in June of 2014. Owned by Lissa and Gary Brown, of Flourtown, Gus began showing signs of nausea and subsequent vomiting and was diagnosed with a slight heart murmur at four months of age.
After a check-up from Gus’s primary veterinarian, Dr. Andrea Orsher, in Fort Washington, the dog was referred to Dr. Beth Bossbaly, in Levittown, Pa., an American College of Veterinary Internal Medicine (ACVIM) Board-certified cardiologist.
Chest radiographs revealed an enlarged heart but no signs of congestive heart failure. Because of his history, Dr. Bossbaly placed a 24-hour Holter monitor on Gus and gave the Browns a diary in which to record his specific activities and corresponding time of day during the monitoring of any events or periods when they saw Gus’ heart pounding at home. The recording monitor revealed rapid heart rates with arrhythmia that landed Gus in the ICU immediately.
In the process Gus lost considerable weight. “Looking back,” said Lissa, “it seems the genetically destined arrhythmia was progressive … steadily worsening over the next month.”
Brown, an ophthalmologist and former nurse with experience in cardiac surgery, said,” I understood generally the arrhythmia issue, and my background allowed me to read medical and veterinary literature to fully understand Gus’ condition and the treatment options available.”
Next, Gus was referred to the University of Pennsylvania School of Veterinary Medicine, where he was seen by Dr. Mark Oyama, another Board-certified cardiologist. Oyama diagnosed Gus’ condition as a unique form of supraventricular tachycardia (SVT), a congenital electrical defect that permits electrical impulses to travel outside of the normal single pathway, resulting in the accelerated heart rate with which Gus presented.
On four occasions last June, Gus was admitted and discharged from the hospital for recurrent episodes of SVT and treated with various combinations and doses of oral drugs with limited success. In his final three-day hospitalization, Gus experienced problems tolerating IV drugs needed to control his SVT. At one point he collapsed due to a critically low heart rate, requiring staffers to revive him.
Because medical management at Penn Vet’s Ryan Hospital was not enough to control the condition, his best hope was an immediate cardiac ablation procedure performed by Dr. Kathy Wright, a Cincinnati ACVIM specialist in cardiology and internal medicine. The hospital (MedVet Medical and Cancer Center for Pets) is recognized as the premier site for clinical ablations in the U.S. and Canada; more than 70 have been conducted.
This meant Lissa needed to drive the ailing dog from Philadelphia to Cincinnati — 11 hours and 625 miles — for the surgery. “Gus preferred to curl up in the passenger seat and put his head next to the gear shift,” said Lissa, “and rest it on my knee or the arm rest and sleep … I knew my job was to drive safely, not get lost and to get to the veterinary hospital on time.”
So what does an ablation operation involve? Dr. Wright explained, “Special electrode catheters are introduced through veins in the leg and the neck and positioned at key areas within the heart. We do extensive testing … Based on electrical responses, we are able to tell where the extra electrical connection, known as the accessory pathway, is generally located within the heart … Radiofrequency energy is then delivered through a special catheter whose tip is positioned on the accessory pathway.”
The entire procedure in Gus took four hours and 15 minutes. Recovery was quick, allowing the Browns to take him home the following day. Without the surgery and with the severity of Gus’ rhythms, Dr. Wright speculated that he would most likely not have survived more than a year or two. And during that span he would have required several hospitalizations to control the rapid heart rhythm.
Twenty one dog breeds have been documented with accessory pathways, according to Dr. Wright. It has been most commonly seen in Labrador Retrievers (40 percent of the cases). “It was quite a harrowing experience,” Lissa told us last week, “and we are glad that little Gus is terrific now. The only problem is that we lost the training time, so he is a bit of a juvenile delinquent now, getting everything off the counters and demanding attention!”
To find an ACVIM specialist in this area, visit www.ACVIM.org or call 303-231-9933, Ext. 101. Story and photos courtesy of American College of Veterinary Internal Medicine.