DEAR DOCTOR K:
I can hear my heartbeat in my left ear. Should I be worried that I might lose my hearing?
A few years ago a patient of mine asked me the same question. What he was worried about was not that he might have an ear condition which could take away his hearing — he was worried that he might be going crazy!
I told him that if all he heard was his heart, he wasn’t crazy. On the other hand, if he heard the voice of Abraham Lincoln whispering in his ear, he might have something to worry about.
A condition called tinnitus causes unusual sounds in the ears: high-pitched hisses, lower-pitched buzzing sounds, clicking. This is a remarkably common problem; an estimated 50 million people in the United States have it to some degree.
I consulted with my colleague Dr. David Vernick, assistant clinical professor of otology and laryngology at Harvard Medical School. We agreed that what you describe sounds like what’s called “pulsatile tinnitus.” This is a rhythmic thumping or whooshing only you can hear, often in time with your heartbeat.
The most common causes of pulsatile tinnitus include:
- Conductive hearing loss. This type of hearing loss intensifies internal head noises — sounds such as breathing, chewing, and blood flowing through the ear. Conductive hearing loss makes it easier to hear blood flowing through two large blood vessels that travel near to each ear. These are the carotid artery and the jugular vein, which circulate blood to and from the brain. (I’ve put an illustration of these blood vessels, and where they sit in relation to your middle and inner ear, below.)
- Carotid artery disease. The accumulation of fatty buildup (plaque) inside the carotid arteries can create turbulent blood flow. This can cause a pulsating sound.
- High blood pressure. When blood pressure is high, blood flow through the carotid artery is more likely to be turbulent. That turbulence generates the pulsatile tinnitus.
- Blood vessel disorders. Many blood vessel disorders can cause pulsatile tinnitus. These include an abnormal connection between an artery and vein, twisted arteries, or a benign blood vessel tumor behind the eardrum.
- Ear muscle disorders. Tiny little muscles that attach to the bones inside the ear can sometimes go into spasms, and this can cause pulsatile tinnitus.
Ear anatomy and hearing
Conductive hearing loss makes it easier to hear blood flowing through two large blood vessels that travel through each ear. These are the carotid artery and the jugular vein, which circulate blood to and from the brain.
Most of the time, pulsatile tinnitus is nothing to worry about. If it doesn’t go away on its own or becomes really bothersome, talk to your doctor.
Your doctor will likely examine your ears and listen to the blood flow through the arteries in your neck. He or she will listen for an unusual sound that blood makes when it rushes past an obstruction. If your doctor hears this sound, you’ll likely need a test to look for a narrowing or malformation in your carotid artery — and possibly surgery to correct the problem. Otherwise, you may need a hearing test or other additional testing.