Let’s talk heart to heart! Just like with humans, there are several diseases and illnesses that can affect the hear. During exams, your vet will use a stethoscope to listen to your pet’s heart and lungs. During this part of the evaluation, if a murmur is present, the veterinarian will hear an abnormal swishing noise. They will assess which area of the heart they can hear the murmur the loudest and then give it a grade on a scale of 1-6. Unless you are a cardiologist or have had experiences with heart murmurs, the diagnosis can be very concerning. Knowing some of the terminology can help ease some of the concern.
The first group of words describes the location in which the murmur is heard the loudest. Dogs and cats have a very similar vascular system to humans. There are four chambers of their heart (left and right atrium and left and right ventricle).
- Aortic – left side of the heart.
- Mitral – left side of the heart.
- Tricuspid – between the right atrium and the right ventricle.
- Pulmonic – the upper right side.
The cardiac cycle is the “lub-dub” sound the heart makes. Changes in this “lub-dub” pattern are considered a murmur. Depending on when the murmur is heard will give it another term.
- Systole – the phase of the heartbeat when the heart muscle contracts and pumps blood from the chambers into the arteries.
- Diastole – the phase of the heartbeat when the heart muscle relaxes and allows the chambers to fill with blood.
- Continuous – the murmur happens during both the systolic and diastolic phase.
Heart murmurs are then graded on a scale from one to six – with six being the worst. If a heart murmur is caught early and treated, murmurs can be managed long term.
- Grade 1 – Murmur can only be heard in a quiet room after several minutes of listening.
- Grade 2 – Murmur can be heard immediately but is very soft.
- Grade 3 – Murmur has a low to moderate intensity.
- Grade 4 – Murmur is loud by doesn’t have a palpable thrill.
- Grade 5 – Murmur is loud with a palpable thrill.
- Grade 6 – Murmur is loud and can be felt through the chest.
When a murmur is detected, further diagnostic testing will be recommended. Bloodwork and radiographs (x-rays) can further evaluate the condition of your pet’s health. A cardiology referral is also recommended at this time. Don’t be alarmed. A veterinary cardiologist sees dogs and cats with heart problems all day long, every day. They are well versed in heart conditions. They have more diagnostic tools to further evaluate your pet. They can give your primary care veterinarian recommendations for anesthesia as well as how to continue monitoring the heart murmur as the your pet ages.
Some murmurs need to be maintained with medication or supplements. Close monitoring with the veterinarian and cardiologist with adjustments as needed along the way will allow your pet to continue a normal lifestyle.