09/05/2026
Meet little Lucy! 🐾
This sweet 11-week-old kitten has already captured our hearts completely, but she’s also keeping us a little bit on edge.
During her routine vet check-up last week, we discovered that Lucy has a grade 3-4 heart murmur. While it was definitely a startling piece of news to receive, we’re taking a deep breath and following our veterinarian's lead. We’ve decided to monitor her closely and do a recheck in a month to see how she’s growing before figuring out our next steps.
Since we’ve been diving into a lot of research lately, we wanted to share what we've learned about what a heart murmur actually is, how a kitten can get one so young, and why anesthesia requires extra caution.
What is a Heart Murmur?
Normally, blood flows through a healthy heart in a smooth, silent, orderly pattern. A heart murmur is simply an extra sound—a "whoosh" or a swishing noise—caused by turbulent blood flow inside the heart. Vets grade murmurs on a scale from 1 (very faint) to 6 (very loud, often felt as a vibration on the chest). Lucy's grade 3-4 falls right in the middle, meaning it's quite distinct and loud enough for the vet to hear easily with a stethoscope.
Why Do Kittens Get Heart Murmurs at a Young Age?
Heart murmurs in kittens can happen for a few different reasons:
"Innocent" or Physiological Murmurs: Some kittens have temporary murmurs simply because they are growing so fast. The blood is rushing through their tiny, rapidly developing hearts at a high speed. These often disappear on their own by the time the kitten reaches 4 to 6 months of age.
Congenital Heart Defects: Other times, a murmur is structural. This means the kitten was born with a minor malformation, such as a narrow valve or a small hole between the heart chambers, which forces the blood to squeeze through a tighter space.
Early-Onset Heart Disease: Though less common in young kittens, genetic conditions (like hypertrophic cardiomyopathy) can occasionally start developing early.
What are the Risks of Anesthesia?
Because a heart murmur changes how blood moves through the heart, any future procedures requiring general anesthesia (like spaying or routine dental work) carry higher risks.
Cardiovascular Stress: Anesthetic drugs naturally tend to lower blood pressure and depress heart function. In a healthy pet, the body easily compensates for this. In a pet with a heart murmur or underlying heart defect, the heart has a harder time handling those shifts.
Potential Complications: The risks include drops in blood pressure, irregular heart rhythms, or in severe cases, the heart struggling to maintain adequate blood flow.
This is precisely why our vet recommended waiting a month. Letting Lucy grow a bit gives us a clearer picture of whether this is an innocent kitten murmur that she will outgrow, or if we’ll need an echocardiogram (an ultrasound of the heart) to look closer before she ever has to go under anesthesia.
Right now, Lucy is acting like a completely normal, playful, energetic, and fearless little kitten. We are staying positive, showering her with extra love, and keeping a close eye on her.
Send some good thoughts and healing vibes our sweet girl's way for her recheck next month! ✨🐈⬛
