Silent ischemia is a cardiovascular condition characterized by restriction of the heart's oxygen supply without noticeable symptoms. The lack of symptoms and warning signs puts the patient at risk, as the heart may become severely compromised, leading to a myocardial infarction, without any warning for the patient. Incidence rates of this condition vary by nation and there are a number of risk factors doctors can use to determine whether patients need to be screened for silent ischemia to identify the condition before it causes a heart attack.
People at risk for ischemia in general and silent ischemia in particular include individuals with a prior history of myocardial infarctions, people with diabetes, patients with cardiomyopathy, and individuals with certain lifestyle risk factors such as smoking. Some patients who have episodes of silent ischemia also have angina pectoris or myocardial infarctions. These patients notice the chest pain associated with these medical episodes but are not aware they are also experiencing ischemia at other times.
Cardiac stress tests can be used to see how the heart performs under stress to look for signs of cardiac ischemia. Patients may also be asked to wear a Holter monitor, a device that provides continuous monitoring of the heart rhythms. This will allow doctors to identify episodes of silent ischemia, as they occur during the course of the patient's day, as the restriction of blood flow comes with characteristic changes to the heart rhythm.
If people are not treated for this condition, it is possible for a myocardial infarction to occur. The heart's muscle tissue can become damaged over time, forcing the heart to work harder to function. This increases the strain on the heart and can put the patient at risk for further cardiovascular problems. The goal with problems like silent ischemia is to identify them early so they can be treated before permanent damage to the heart is caused.
Treatments can include lifestyle changes including quitting smoking, exercising more, and making some dietary changes. If the patient has a history of risks like high cholesterol, limiting and controlling those risks may be recommended to improve heart health. Patients will also be monitored closely for signs of changes to cardiovascular health so interventions such as stents can be provided in a timely fashion in the event the patient begins to experience complications. Being aware of a history of silent ischemia is important, as patients need to be on the lookout for symptoms of cardiovascular problems in order to seek prompt medical treatment as complications arise.