Cardiac cephalalgia is a symptom of the most common type of heart disease - ischaemic heart disease - due to narrowing of the main arteries supplying heart muscle (coronary stenosis).
This is a very rare syndrome, as when I have talked to cardiologists they have sometimes been sceptical of its existence.
At the time of a heart attack or angina episode about 6% of people will report headache at the time of the onset of the heart problem as well as the dominant symptom of chest or arm pain (according to one survey of about 150 people).
However, there are some very convincing cases of people with narrowed coronary arteries who experienced headache during their heart attack or angina episode.
While their arteries were being treated at angioplasty headache appeared when the angioplasty balloon was inflated.
These people reported resolution of headache symptoms once the arteries were treated.
According to the largest review of 34 cases, about half of cardiac cephalalgia cases will be having a heart attack, about 40% will be having angina and about 10% of cases are experiencing a heart rhythm disturbance.
There is a list of all 41 published papers on cardiac headaches at the foot of the page.
What types of heart disease cause headaches?
These heart conditions are serious as up to 12% of people died of the heart disease that had caused their headache condition.
The headache of heart disease is usually dull, one sided, and experienced in the face, eye or forehead. It can even be felt in the back of the head (about 20% in one series were occipital headache).
There has been a recent case of Thunderclap Headache caused by an acute heart attack.
Like angina, heart-disease headaches are brought on by exercising, including the exertion associated with sexual activity.
The most comprehensive review of cardiac cephalalgia by Drs Wie and Wang 2008 reviewed 34 cases.
It is interesting to note that 11/34 cases had eye pain as a manifestation of their cardiac condition. This may be a clinical pointer - consider heart disease in exertional unilateral eye pain. Cardiac pain can also present as isolated ear pain.
Headache has been noted in up to 6% of angina sufferers (out of a series of nearly 200 people), yet none had pure headache.
This means that heart disease should not be the first consideration in diagnosis of headache. However, as fatal cases are recorded, the diagnosis is something anyone treating severe headaches should know.
An older person with cardiovascular risk factors who presents with thunderclap headache or exercise headache would be the sort of person I'd have in mind.
My own experience of cardiac cephalalgia was an older man presenting to hospital with occipital headache and breathlessness, who subsequently was diagnosed as non-ST elevation MI and congestive cardiac failure. Another gentleman, in his 70s, developed headaches on exercise which were related to angina.
What diagnostic tests should I perform?
If you think of this diagnosis, then - usually a treadmill test is necessary to try and establish a diagnosis. Descriptions of further cardiac investigations are beyond my area of expertise.
Any exercise induced headache should also have brain imaging, usually a CT Brain is sufficient.
However, if the headache was thunderclap, then a Lumbar Puncture should be performed.
Why is heart pain felt in the head?
The explanation usually given for heart disease being sensed in the head is the phenomenon of "neural convergence".
The vagus nerve is the main nerve from the heart which transmits angina pain to the brain. In the upper part of the spinal cord, fibres from the vagus nerve converge (or mix) with fibres from the trigeminal nerve.
The trigeminal nerve is that main sensory nerve of the head and face. It is through activation of the trigeminal nerve from these connecting vagus nerve fibres that heart attack pain or angina pain becomes a heart disease headache or cardiac cephalalgia.
If there are no references listed, please notify me, as this box should contain a list of information sources, or a link to a 'Systematic Review' of the topic discussed on this page.