Doc B. returns with comments on heart disease, pharmacological stress tests and the recent unexpected death of
Tim Russert.
L.P.: What is the latest on
NBC anchor,
Tim Russert's sudden death from heart disease?
Doc B: His heart doctor,
Dr. Oz was on
Larry King. Dr. Oz explained that with heart disease, you can never really tell in advance how to prevent it. What are the odds that Tim could have done something different? Dr. Oz explained that
"Of the 450,000 people a year who die of heart attacks in this country, probably half of them never knew they were at risk of a heart attack. It's because the heart doesn't really have pain fibers. In fact, the only reason you ever feel any pain when you're having a heart attack is because the nerves in the heart cross other nerves -- from your chin, your arm or from the chest and the spinal column. And they short-circuit each other out. And that creates this referred pain that in cardiology and cardiosurgery we recognize to be angina."L.P.: If the plaque is not limiting blood flow is that really such a big problem?
Dr. B: Dr. Oz also explained this issue pretty clearly, "... this is a big wake-up call for a lot of Americans, as well -- is that a lot of the plaques that we have are not flow limiting. And by that I mean they don't cause a limitation on the amount of blood that courses through the veins that go to our heart.... "
L.P. : How did that cause the death of Tim
Russert?
Dr. B.: Based on what I have read, Tim had a cardiac arrest. It was probably an acute dissection, rupturing plaque that's causing a blockage of a coronary artery. The temporary blockage caused a heart attack -- a fatal arrhythmia.
L.P. Did they try to save
Russert?
Dr. B.
Dr. Michael Newman told Larry King that a defibrillator, a heart-shocking device, was unsuccessful in saving
Russert. "
L.P.: Can't stress tests determine the condition of a
patient's heart?
Dr. B.: After releasing autopsy results,
Dr. Michael Newman said
Russert had passed a stress test on April 29. He had even worked out on a treadmill the morning of his death.
"
Russert, age 58, was known to have asymptomatic
coronaryartery disease (atherosclerosis), which resulted in hardening of his coronary arteries," Newman said. "The autopsy revealed an enlarged heart and significant atherosclerosis of the left anterior descending coronary artery with (a) fresh clot which caused a heart attack resulting in a fatal ventricular arrhythmia."
L.P.: Did
Russert have any symptoms?
Dr. B.: As I understand it,
Russert's stress test on April 29 was "normal." Dr. Newman said. "At a high level of exercise he had no symptoms." Newman said
Russert's blood pressure and cholesterol were "well-controlled." see
http://www.people.com/people/article/0,,...L.P. : Which is better, pharmacological stress testing or exercise stress testing?
Dr. B.: Imaging tests are more sensitive than the exercise ECG in the detection of severe (three vessel and left main) disease . . . the sensitivity for severe disease was 93 to 98 percent with planar thallium imaging, stress
echocardiography, and
SPECT perfusion imaging compared with 86 percent for exercise ECG testing. Furthermore, it you have arthritis or are in poor physical condition, you may not be able to exercise at a high enough level to adequately stress your heart without the pharmacological agent.
L.P.: What is the best nuclear pharmacological stress test?
Dr. B.: The modern nuclear pharmacological testing of choice is rapidly becoming the
Adenosine stress test. The test can help determine if there is adequate blood flow to the heart during activity versus at rest.
Adenosine does not increase your heart rate.
Adenosine dilates blood vessels leading into the heart, increasing blood flow, therefore simulating exercise for patients unable to exercise on a treadmill. It is the fastest acting pharmacological agent and while it may produce symptoms of shortness of breath, within seconds of discontinuing the
Adenosine, the symptoms almost always stop.
L.P.: Are there any contraindications to using
Adenosine.
Dr. B.: The only major restriction is not to use
Adenosine if a patient is actively wheezing with
Bronchial Asthma. If the patient is not actively wheezing, most facilities such as the Cleveland Clinic will go ahead and proceed with an
adenosine stress test despite the patient having a history of asthma. Some will opt to use a
Dobutamine stress test instead if the patient does not have tachycardia (fast heart rate) or hypertension (high blood pressure.)
The Journal of Nuclear Cardiology 2007 14:827-34 has reported a new study that 6 minute
Adenosine infusion can be safe in patients with mild asthma or
COPD. In my opinion, it really is a judgment call for the physician based on his training and experience with no wrong answer.
L.P. What is the best advice to reduce your chance of heart disease?
Dr. B: Exercise. Eat a low fat diet. Keep your cholesterol level low. Keep your blood pressure low. If you have diabetes, keep your sugar levels under control! Have regular check up with your doctor. And, last but not least, do not smoke!
L.P. Thanks, Dr. B.
Disclaimer: This article should not be used as a substitute for medical advise or treatment. As always, if you need medical treatment or advice, immediately consult your physician.