Cardiac Services

Nuclear Stress Testing with State of the Art Dual Headed Nuclear Camera

Nuclear cardiology allows your physician to detect blockages in the heart's blood vessels using weakly radioactive substances and pictures are thereafter generated to determine the flow of blood into your heart muscle. Typically, the imaging is obtained after a treadmill exercise test, but sometimes if the patient cannot perform one, pharmacological testing is utilized.

The total dose of radiation is less than that of a chest x-ray.

Heart Specialists PC of Southern Connecticut, has had extensive experience in nuclear cardiology testing. Our nuclear cardiologist has been in this field since 1981 and was one of the first to take and succeed in a nuclear cardiology examination in 1995.

The following services are available:

1. Exercise and rest myocardial perfusion imaging (also called a MIBI), Cardiolite,Myoview or Thallium stress tests.

The non-invasive assessment of coronary artery disease via treadmill stress testing can detect blockages significant enough to prevent adequate blood flow to the heart during exercise. The radioactive material be it Technetium (MIBI, Cardiolite, Myoview) or Thallium, is injected at peak exercise on the treadmill or after certain duration of time following pharmacological stress. Nuclear imaging is then begun generally within 30 minutes of injection of the radionuclide activity. A series of pictures are performed with our newly acquired dual head GE Nuclear Cardiology Camera which utilizes updated technological advancement. Total duration of time for imaging varies between 15 and 30 minutes.

You may or may not be called for a second set of pictures depending on the protocol utilized. If you are called for a second set of pictures (resting imaging), the latter would be performed without stress and also take approximately 15-30 minutes. This could be done on the same day or the following day depending on the protocol utilized.

Stress or Pharmacological Stress Nuclear Imaging is combined with Gated Study that evaluates the function of the left ventricle and calculates the ejection fraction. The ejection fraction is probably one of the most important prognostic markers of heart disease.

If stress testing is not feasible either because of body limitations (arthritis or vascular disease) or the inability to attain a certain target heart rate which is essential for stress testing, then pharmacological stress testing would be utilized. Pharmacological agents that are used are Adenosine or Persantine. The pharmacological agents are generally contraindicated in patients with asthma. Their safety profile is very good and accuracy as good as regular stress testing. These agents are used to dilate the arteries of the heart but in a sense do not dilate the abnormal vessels (narrow vessels) as well as the normal vessels and nuclear imaging is utilized shortly after to highlight this characteristic.

The half life of Adenosine which is the main pharmacological agent in our lab, is a few seconds and therefore most side effects are over in 15 seconds.

2. Radionuclide ventriculography (also called RNV or MUGA test).

This test utilizes nuclear imaging to calculate the left ventricular ejection fraction which is an estimate of the power of the pump. It also detects the presence of prior heart attacks and provides a guide to your physician/cardiologist in the appropriate selection of drugs for your care. MUGA's can also detect aneurysms and pseudoaneurysms of the heart.

Is it safe?

Nuclear stress testing is extremely safe. The radioactive agent has no side effects. There are a few side effects with pharmacological agents, the most common being a flushing and sometimes
vague abdominal and chest pains. However, be reassured that the test is constantly being monitored by your physicians who are highly trained and experienced in performing these tests, and antidotes are readily available to combat any major side effects. Theoretically, the risk of major complications are in the order of 1/10,000.

How should I prepare?

You should not eat for approximately 3-4 hours before a nuclear stress test. Please consult your doctor if any medications should be withheld. Please wear loose clothing and bring comfortable walking shoes. If you are a diabetic, please inquire about instructions regarding your diabetic medications.

When are the results available?

Our physicians read every test the same day. The results after a completed test (stress and rest) are communicated to your doctor within 24 hours of its completion by fax.

Our cardiologists are board certified in Nuclear Cardiology.  Our nuclear laboratory is accredited by ECANL, and organization established to recognize quality in the practice of nuclear cardiology.