Dr Maite Tome, consultant cardiologist at the Heart Hospital in London, discusses the many causes of chest pain in the cardiomyopathies.
Chest pain is one of the main reasons why people attend hospital accident and emergency departments. Every year doctors treat millions of people with chest pain.
People with chest pain may fear a heart attack but there are numerous causes of chest pain, from a light inconvenience to serious and life-threatening events.
The most important job of the doctor is to rule out a life-threatening cause of chest pain and it is advisable for anyone suffering a new onset of chest paint to seek urgent medical advice.
What are the causes of chest pain?
Any organ or tissue in your chest can be a source of pain, including your heart, lungs, esophagus, muscles, ribs, tendons and nerves. (The list at the bottom of the article summarises the most common causes of chest pain).
Cardiac pain due to lack of oxygen and blood supply to the heart muscle is called ischaemic chest pain. This pain is most likely central and diffuse in the chest.
It can irradiate to the neck, jaw, both arms and occasionally to the back. It can feel oppressive and crushing. Often it can be identified from precipitating factors such as exercise, strong emotion, walking up hill, a strong meal, etc. It relieves with rest and or cardiac nitrate medication. It's often associated with breathlessness.
This unbalance in the demand and supply of blood and nutrients to the heart muscle is most commonly caused by ischaemic heart disease (IHD). In IHD, the coronary arteries (the vessels that supply the heart with blood) become blocked with cholesterol plaques and starve the heart muscle of appropriate nutrients, resulting in pain.
If the nature of the blockage in the coronary arteries is a narrowing, the type of pain is generally predictable. The pain, usually lasting less than five minutes, starts during exercise and relieves with rest. It is clearly reproducible and does not happen at rest. This type of pain is called stable angina.
However, when an acute rupture of plaque occurs, then a clot inside the vessels stops the blood flow completely. If the occlusion lasts long enough the muscle depending on that vessel with suffer (unstable angina) causing pain lasting a few minutes or will start dying, a myocardial infarction (MI) with the chest pain lasting longer than a few minutes. This sort of event is called a heart attack.
Patients with the onset of central chest pain need to seek medical attention urgently as their lives could depend upon it. The treatment is targeted to try to open the blocked vessel as soon as possible with strong blood thinning drugs or with a balloon angioplasty.
Patients with some cardiomyopathies, mainly hypertrophic cardiomyopathy and some patients with dilated cardiomyopathy, suffer with ischaemic chest pain in the absence of coronary artery disease.
It is very important that your doctor first excludes coronary heart disease as the origin, using tests such as coronary angiogram, multislice CT, nuclear scan or exercise/exercise echocardiogram before assuming the pain is due to cardiomyopathy. Your doctor will be guided by your risk factors for coronary artery disease such as your age, smoking habits, weight, family history, hypertension and diabetes, and previous history of IHD, to decide the best test for you.
Hypertrophic cardiomyopathy (HCM)
One of the most common symptoms of HCM is exertional chest pain. It occurs during exertion or at the peak of exercise. It is always relieved with rest and it is clearly reproducible. There are several causes for this type of pain. One is that the coronary artery walls are abnormal and thicker. The other, and probably most common, is the lack of sufficient blood supply at the peak of exercise due to the thickened muscle needing more oxygen than is available.
Patients with HCM and left ventricular obstruction (LVOT) typically develop chest pain on exercise. The oxygen demands of the muscle walls again are not met and this results in chest pain.
The treatment is based on beta blockers and calcium channel blockers. In some cases surgery or an alcohol septal ablation is required.
Patients with apical HCM (when the muscle thickening is at the tip or apex of the heart) are most likely to suffer with chest pain of this kind.
While in most cases it does respond to calcium channel blocker therapy, it can be resistant to the therapy and difficult to treat. Research is currently being conducted to find an efficient treatment for this patient group.
Dilated cardiomyopathy (DCM)
Patients with DCM sometimes complain of chest pain, but it is less common than in patients with HCM. It is usually caused by exertion due to high pressures on the heart wall impeding appropriate blood supply to the heart muscle along with more oxygen demand.
Heart failure medication aims to improve these symptoms and particularly helpful are beta blockers. It is important to remember that even though chest pain does not always mean a heart attack, whenever chest pain occurs it is a warning sign that the heart is suffering.
It is always advisable to rest and let the doctor know so he can adjust your medication to reduce the recurrence of chest pain.
General advice
Some patients with cardiomyopathy diagnosed at a young age are used to cardiac symptoms. But it is important to remember that age and other diseases, such as high blood pressure and high cholesterol, can affect patients with cardiomyopathy. Therefore we all need to be vigilant and, if a new episode of chest pain occurs, seek medical attention.
It is a good idea to ask your doctor for a copy of your ECG and keep it in your wallet. Those with cardiomyopathy have a typically abnormal baseline reading and it may be of enormous help to a doctor not familiar with your case to see it.
While there is no treatment yet for the cause of cardiomyopathy, there is treatment for ischaemic heart disease - that is prevention.
For patients with a genetic heart condition it is even more important to prevent high cholesterol, smoking related diseases, obesity and other risks for coronary heart disease.
Cardiac causes of chest pain
Non-cardiac causes of chest pain
Dedicated to Damian McLoughlin, who died age 20 of cardiomyopathy. This site is supported by Damian's family and friends.
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