Patient Condition and History

Lucas, a 10 years old, neutered male Beagle, was adopted from a shelter several months previously. His new owner, Mrs. Michelle Saltzman of Bedford, MA, witnessed episodes of weakness, exercise intolerance, disorientation, collapse and syncope (fainting). Dr. Patricia Berchtold from Chelmsford Animal Hospital, MA, examined Lucas and also consulted with a cardiologist to conclude that Lucas has a Chronic Valvular Heart Disease (stage B2 according to the ACVIM Classification of Heart Disease and Heart Failure). Lucas was placed on medications (Benazepril), ordered to avoid excessive activity, and it was recommended to further examine Lucas’ heart rhythm through a Holter monitor or an event recorder.

A Holter monitor and Event recorder are devices used to record ECG, the electrical signal of the heart, in order to diagnose arrhythmia (abnormal heart pace) and assess its severity. However, these devices have several limitations. They involve wires, known as leads that attach to the body. Therefore, when worn by a dog or a cat they require shaving, attaching leads to the chest, and bandaging, to protect the device from the pet chewing or pawing at it. In addition, the devices only record data for a few days, and in the case of event monitors, require the pet owner to activate it when an event is occurring. Moreover, the devices do not provide real time data. Instead, after the recording period has ended the devices are sent to a specialized laboratory for data extraction and interpretation.

For all of these reasons, Michelle Saltzman chose to also buy a PetPace smart collar. The collar, worn conveniently on the neck like a regular collar, provides multiple physiologic and behavior attributes, including vital signs such as pulse rate. The collar collects the data noninvasively, continuously and is designed to be worn long term. The data is accessible anytime, anywhere, and alerts for suspicious events are sent in real time.

The collar has additional advantages that are useful for the monitoring of patients with heart disease. It reports respiratory rates, heart rate variability (HRV), and activity level and it creates sophisticated analytical reports, all contributing to the assessment of the disease severity and its prognosis.

Michelle placed a PetPace smart collar on Lucas to complement the treatment protocol instructed by Dr. Berchtold.

 

Monitoring Data

The PetPace smart collar worn by Lucas revealed that a few times every day he has brief episodes of high pulse rate, reaching the 160- 180 beats per minute range. These events usually follow some moderate activity but the pulse rate appears higher than expected for this level and pattern of activity.

 

* Typical pulse rate tracing chart of Lucas, a 10 y.o. Beagle with heart disease and syncopal episodes, showing occasional brief tachycardia (elevated heart rate) events.

* Typical pulse rate tracing chart of Lucas, a 10 y.o. Beagle with heart disease
and syncopal episodes, showing occasional brief tachycardia (elevated heart
rate) events.

 

* Activity chart from the same time as the pulse chart above. Moderate or low activity levels precede the tachycardia events.

* Activity chart from the same time as the pulse chart above. Moderate or low activity levels precede the tachycardia events.

 

Statistical analysis of Lucas’ data, available through the PetPace Health Report, provided additional insights into Lucas’ condition.

• The daily average pulse rate, calculated from hundreds of measurements every day, was slightly higher than normal (87.8 beats per minute).

• The minimum pulse rate (58.6 beats per minute) was normal, meaning the heart was able to relax during rest.

• Overall daily average respiratory rate (18.4 breaths per minute) was normal, as was the minimal respiratory rate (11.4 breaths per minute). Respiratory rates are commonly used to monitor patients with heart disease.

• HRV (Heart Rate Variability), a marker of cardiac disease, was slightly lower than normal (high HRV is good).

• All values were relatively stable and consistent through time, and did not show worsening trends.

 

* Tracing of Lucas’ daily minimal respiratory rate showing normal low respiratory rates during rest. Elevation of resting respiratory rate is a negative indicator of heart condition.

* Tracing of Lucas’ daily minimal respiratory rate showing normal low respiratory rates during rest. Elevation of resting respiratory rate is a negative indicator of heart condition.

 

It is interesting to note, that Lucas is a fairly active dog, despite his condition. Just looking at his activity data it would have been impossible to know that he has a serious cardiac disease.

 

* Accumulated daily activity chart of Lucas, showing consistent, good activity level.

* Accumulated daily activity chart of Lucas, shows a consistent, good activity
level.

 

An additional analytical tool, an HRV Vs. Pulse plot chart, is attached below. For creating this chart, an HRV index called VVTI (Vaso-Vagal Tonus index) is plotted against the corresponding pulse data recorded at the same time. Preliminary investigation is showing a statistical correlation between excessive numbers of plot points below the normal range (red dots) and various serious diseases. Lucas’ chart shows that 3.6%, a higher then normal percentage of data points (red points), fall below the normal range.

 

*Lucas VVTI Vs. Pulse chart showing abnormally high amount of points below the normal range (red points).

*Lucas VVTI Vs. Pulse chart showing abnormally high amount of points below the
normal range (red points).

 

Following Dr. Berchtold’s advice, Lucas wore a Holter monitor for 24 hours to measure his heart rhythm and rate and correlate it with the periods of high heart rates recorded by the Pet Pace Collar. The average pulse values measured by the Holter precisely match those reported by the collar.

 

Discussion

Holter monitor and event recorder are important diagnostic tools in certain heart diseases. Unfortunately, they are not used frequently enough due to practical reasons. The PetPace collar, used in this case to complement the management of Lucas’ heart disease, correlated well with the heart rate values reported by the Holter. Moreover, the collar provided additional valuable information regarding the patient’s condition, including respiratory rate values, activity patterns, and HRV analysis.

“The PetPace smart collar provides a range of clinically relevant attributes for the monitoring of dogs and cats with heart diseases” said Dr. Asaf Dagan, DVM, Diplomate ABVP (Canine and Feline practice), and PetPace’s Chief Veterinarian. “It adds a new level of objective, quantifiable data and together with analytical tools it will advance our understanding of these pathologies and enhance our ability to treat them,” he added.

“I loved seeing the data provided by the collar, which complements the owner’s reports, blood tests, imaging and ECG data that we collected on Lucas,” said Dr. Patricia Berchtold, from Chelmsford Animal Hospital in Chelmsford, MA, and Lucas’ veterinarian. “It helps me as a clinician to produce a comprehensive picture of his condition, monitor it over time and guide my clinical decisions”, she continued.

 

Conclusions

Chronic heart diseases are common in dogs and cats. They frequently require medications, long-term monitoring and periodic clinical assessment. The current home monitoring techniques, including owner observations and wearable ECG devices, have limitations. The PetPace collar significantly improves this situation.

The fact that the collar can be easily worn long term, and that its data and reports are available in real time to both pet owners and caretakers, make it a worthy addition to the home management of cardiac patients.

While activity data is important to complete the picture it lacks sensitivity and specificity. Monitoring activity alone falls short of being a clinically useful tool in the context of cardiac patients.

“This collar gives very cool information that I can share with my vet”, says Michelle Saltzman, Lucas’ owner. “Lucas has no problems wearing it and I know he needs it. I only wish we had it for some of our other senior pups we adopted in the past”.