Acute Coronary Syndrome
Acute Coronary Syndrome or ACS is a catch all term used to describe a set of symptoms consistent with acute myocardial ischemia when the symptoms are not pathognomonic. Myocardial ischemia is a condition in which insufficient blood flow is reaching the heart muscle. This is usually a result of atherosclerotic plaques building up in the coronary arteries. Symptoms The symptoms of ACS are typically tightness in the chest that radiates into the left arm, anxiety or a sense of impending doom, and shortness of breath. Other symptoms that might occur are nausea, vomiting, sweating and palpitations. In female patients, the elderly, and those with diabetes there is a higher occurrence of atypical presentation. This can translate to other, non-specific, symptoms such as feeling weak or lightheaded to a complete absence of symptoms.
There are three distinct subtypes of ACS:
• Unstable Angina
• non-ST segment elevation myocardial infarction
• ST segment elevation myocardial infarction
Diagnosis of ACS usually involves an Electrocardiogram. Elevation in the ST segment indicates that damage has occurred to the muscle and that intervention is required immediately. In the absence of ST segment elevation, it is more difficult to distinguish between unstable angina and non-ST segment elevation myocardial infarction. Blood tests can be administered to look for increases in cardiac enzymes. The most accurate indicators for myocardial infarction are increased Troponin I and Troponin T. A second, common predictor is an increased Creatine Kinase level. Another diagnostic tool that can be employed is the ACI-TIPI. The ACI-TIPI is a rough algorithm that uses demographic information and EKG information to provide an estimate of the likelihood of myocardial infarction.
In the event of ST segment elevation myocardial infarction, there are several treatment options. Aspirin is often administered on-site by paramedics to reduce clot size. Beta blockers are often administered to reduce the work load on the heart. Anticoagulants, such as heparin, may be administered to prevent further clots. ACE inhibitors are often administered to prevent some of the heart enlargement. Clearing the blockage as soon as possible is key to patient survival in the case of ST segment elevation myocardial infarction. In most cases an angioplasty and stent placement is performed within an hour or two when possible. Doctors can also use intravenous Thrombolytics to break up clots. For non-ST segment elevation myocardial infarction, the treatments tend to be the same, though without the same time constraints. If an angioplasty is not a viable option due to recent surgery, a bleeding disorder, or multiple blocked arteries, coronary artery bypass surgery can be used to restore blood flow.