Silent myocardial ischemia, called silent myocardial infarction in more severe forms, is a heart condition that causes the suffering of myocardial cells (in the heart) following a partial or total disruption of the flow of a feeding artery of the heart. The affected person does not feel discomfort, pain, or other symptoms. It often reflects a failure in the propagation of nerve impulses to feel pain, that is to say, neuropathy, or increase the threshold of pain perception. The dangers of this condition are of course related to its asymptomatic nature: the patient does not realize that he is suffering while parts of his heart muscle cells are dying. This condition is often encountered in diabetic patients, in whom the complications of the evolution of the diabetes, neuropathy, destroys part of certain nerves, resulting in a reduction or even a complete absence of pain sensation in the area in question: in this case, it is the cardiac nerves which lose sensation.
The disease is asymptomatic by definition. This is why it is described as "silent". But although symptoms are absent, the disease itself, in turn, evolves. It can cause a myocardial infarction (rapid necrosis of cardiac cells).
Diagnosis is based on the observation of an electrocardiogram (recording the electrical activity of the heart) and other specific tests:
- an electrocardiogram, or ECG;
- a physical ECG: recording of cardiac activity during physical exertion, typically on a conveyor belt or bicycle;
- Holter ECG recording (recording made over 24 to 48 hours);
- myocardial scintigraphy, to view the areas where cells are damaged;
- a stress echocardiography, which compares the cardiac activity at rest and during exercise.
It is recommended to perform these examinations regularly in certain types of people, including diabetics of a certain age and holders of other factors of cardiovascular risks such as hypertension, excess cholesterol, smoking, obesity...
The treatment will be based on the same terms as that of the conventional myocardial ischemia, and depend on the results of these examinations. If this is not done, as is already recommended in diabetes, smoking must be stopped, a well balanced diet must be adopted, and other cardiovascular diseases such as high cholesterol or high blood pressure must be treated. The treatment is usually surgical for revascularization of the injured heart, sometimes the stent area. In addition, a suitable medication will be prescribed as a follow-up. Regular monitoring is then required.