Answers to Common Questions
Learn more about medical tests: how they work, what the results mean, and how heart conditions are diagnosed.
A lipid panel is a blood test that measures fat and fatty substances in the blood. Typically, this panel measures cholesterol and triglycerides to identify lipid disorders that increase cardiovascular risk. Treating lipid disorders with lifestyle changes and medication, when necessary, can help significantly reduce risk for heart disease.
In a patient with tachycardia, it is important to assess the left ventricular (LV) function and to rule out structural heart disease. Also the right ventricular (RV) function needs to be assessed. In addition, assessment of the heart valves is essential and can be done by echocardiogram.
Mouaz H. Al-Mallah, MD, FACC
I am 76 years of age. My echocardiography report shows that I have mild diastolic dysfunction. My EF is 69%. How dangerous is it? What are the risks involved?
The finding of mild diastolic dysfunction on an echocardiogram is not concerning. Echocardiograms, or ultrasounds of the heart, assess the left ventricular function, valvular function, and some intracardiac pressures. An ejection fraction of 69% is normal (normal is anything above 50-55%), meaning that your heart is pumping strongly. Mild diastolic dysfunction means that the heart muscle is slower to relax as it fills with blood before pumping it to the body. It is actually a common finding with age, and is considered a normal finding in patients over age 65 as there is mild increase in the stiffness of the heart muscle with age. However, this does mean that the stiffness will increase with time or cause symptoms. There is no danger or risk involved in mild diastolic dysfunction on your echocardiogram. This finding does not merit further testing or any changes to your medications.
Michelle M. Kittleson, MD, PhD
Director, Heart Failure Research
Director, Post-Graduate Education in Heart Failure and Transplantation
Cedars-Sinai Heart Institute
If a patient has had two negative cardiac enzyme tests and a negative electrocardiogram (EKG), what are the chances that a second EKG would be positive?
I assume this question addresses patients with chest pain in the emergency room. If such a patient had two negative cardiac enzyme tests and a negative EKG, the chances that a second EKG would be positive depend on many things. This is related to the patient's pre-test probability of having acute coronary syndrome or heart disease as well as how typical are his or her symptoms. Although the second EKG is unlikely to be positive if the patient has negative enzymes, a negative first EKG and no recurrence of symptoms, the chances of it being abnormal is not 0%. If the first EKG was done when the patient had no symptoms and he/she experienced recurrence of symptoms in the emergency room and an EKG is done while he or she is having chest pain, then the EKG is likely to be positive.
Mouaz H. Al-Mallah, MD, MSc, FACC, FAHA, FESC
It’s quite common and understandable after a heart attack to wonder whether a test could have prevented it by identifying blockages in the blood vessels of the heart. However, there isn’t any test that can reliably do this just yet, for several reasons.
The majority of heart attacks, especially in previously healthy individuals without symptoms, occur at locations where the blockage (caused by cholesterol plaques) is only mild. Unfortunately, many of the tests we have are good at identifying severe build-up of the plaques, but do not pick up mild blockages that don’t limit blood flow. The article you are referring to discusses the role of echocardiograms (an ultrasound of the heart). This test generally does not provide any information on whether there are blockages or not. One day medical science may advance to the point that we have tests to accurately predict which plaques are the most likely to lead to heart attacks. In the meantime, however, we also have to be careful about inappropriate testing, and avoid situations where the test performed doesn’t give a lot of information and can even lead to harm.
I also want to make a final point: Although we can’t predict heart attacks perfectly, we do know that a healthy lifestyle is beneficial for reducing the risk of heart attacks as well as preventing its complications. So the things you have done, such as exercising regularly and eating healthy, are all very important and helped you get better, and I definitely encourage you to keep them up!
Siqin Ye, MD, MS
Doctors often diagnose PAD by using the ankle-brachial index (ABI) to assess blood flow to the legs. The ABI is a simple test that can be done in your doctor’s office. During the test, you lie flat while your doctor measures the blood pressure in both arms using a standard blood pressure cuff and a small hand-held Doppler ultrasound probe. The ultrasound probe detects the first sound of blood flow as the cuff is deflated; that’s the upper number in your blood pressure. Your doctor then measures the blood pressure in both ankles by placing an inflatable blood pressure cuff between the ankle and calf and again using the Doppler ultrasound probe to listen for blood flow.
The next step is to calculate the ratio of the highest ankle pressure to the highest arm pressure on the same side of the body. This is the ankle-brachial index. If the blood pressure in the ankle is a lot lower than in the arm, it is a sign that a blockage is interfering with blood flow to the lower leg.
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