How do I count my pet's sleeping breathing rate with heart disease, and what number is too high?

When a dog or cat has heart disease, the number of breaths they take while asleep is one of the simplest things you can measure at home. It costs nothing, takes a minute, and a change in it can show up before other signs. Your vet or cardiologist decides what the number means for your pet. Your job is to count it the same way every time and keep a record.

How to count sleeping breaths

Tufts’ HeartSmart cardiology service describes the method: count “how many times your pet’s chest rises and falls in one minute,” counting each rise as one breath, while your pet is “at rest or sleeping.” Counting for 30 seconds and doubling works too.

Practical tips (no veterinary source):

• Wait until your pet is in calm, deep sleep. Skip moments of dreaming, twitching or purring, and the first minutes after play or a walk.
• Use a timer, not a guess. The free sleeping breathing rate counter lets you tap each breath for 30 seconds, doubles it to breaths per minute and keeps a printable log.
• Count in the same room and at a similar time of day, so readings are comparable.

What number is normal? Sources differ

There is no single cut-off that every source agrees on:

• The ACVIM cat guidelines recommend that owners monitor the resting or sleeping rate “with the goal of maintaining the respiratory rate <30 breaths/min.”
• A 2016 study of pets whose heart failure was well controlled with medicine found that “most dogs and cats with CHF that is medically well-controlled and stable have SRRmean and RRRmean <30 breaths/min at home,” and that pets with heart disease but no signs had average sleeping rates under 30.
• Tufts says that “in most dogs and cats, the breathing rate is usually less than 35 breaths per minute at rest or during sleep.”

So 30 is a common reference point, not a hard line. Your vet may give you a different number for your pet, and whatever they tell you, their number wins.

Your pet’s own usual number matters most

For dogs with mitral valve disease, the ACVIM guidelines say that “identification of increases in resting respiratory rate above normal baseline has the best predictive value for impending clinical decompensation.” In plain terms: a rate that keeps creeping up from where your dog usually sits is the earliest warning sign that heart failure may be developing or getting worse.

That is why one reading tells you little and a record tells you a lot. Count on several calm nights while your pet is well so you know their usual range. For cats, the ACVIM guidelines note that “owner-recorded resting or sleeping respiratory rate can provide useful information for adjusting medication,” so your log is useful to your vet as well as to you.

Keeping the routine going

How often to count depends on your pet’s stage of heart disease and treatment, so ask your vet for a schedule and write it down. Practical tips (no veterinary source):

• Pick one moment that fits your evening, such as when your pet settles for the night, and set a reminder.
• Write the date, time and number each time, plus anything unusual: a hot day, a missed or late heart medicine, coughing, less appetite.
• If someone else looks after your pet, show them how to count and where to write it.
• Bring the record, or a chart of it, to every recheck. A trend over weeks is far more useful to a cardiologist than a number remembered in the waiting room.