Reader: Three years ago I began having chest pains during my brisk walks. My family physician advised that my symptoms were typical of angina and referred me to a coronary specialist.

After two stress tests, I had an angiogram performed at a heart hospital, and the results showed no obstructions in my arteries. However, I continue to have chest pain when walking. My doctor prescribed nitro tablets to relieve the pain. It also ends when I stop and rest.

Can you explain the cause or suggest further tests or treatment?

Dr. Zipes: I am surprised that the coronary angiogram showed no blockage because the history you relate about your chest pain is quite typical of angina. There is an entity of narrowing in small vessels called microvascular angina wherein the blockages are present in very small coronary arteries and not visualized in the usual coronary angiogram. This occurs more commonly in women. Also, some people with angina and normal angiograms can have coronary spasm, or intermittent narrowing. The angiogram could look normal if the spasm was not present at that time.
There are additional tests that can be done. I would suggest you consult with your cardiologist. In many individuals, taking nitroglycerin prophylactically—that is, before the activity which causes the chest pain and then waiting a few minutes for it to take effect—can prevent the pain altogether. It is important to note that assuming you do not have coronary artery spasm, the prognosis for people without major blockages on the angiogram is generally quite good.

Appropriate Treatment is Key

Reader: In October 2003, I was playing tennis with a friend—just for fun, not very strenuous—as we did quite often. That night I felt fine and fell asleep as usual.
Upon awakening, I felt as though I had been embalmed and was stiff from the waist down. It was quite some time before I could move enough to even get up to go to the bathroom. For almost 21⁄2 weeks, the pain was terrible. Then one morning—the pain was gone.

Since then I've had no pain, but I walk like I was drunk. Sometimes I take a step sideways or backwards to keep my balance or veer from side to side.

I did not call anyone because I felt they would hospitalize me. I just couldn't go and leave my animals with no care. It was about three weeks after the problem that I sought a doctor's help. An MRI showed many TIAs but no real brain damage. What happened to me? Does it have a name?

Dr. Zipes: What you describe certainly sounds like a neuromuscular problem and finding evidence for transient ischemic attacks (TIAs) by MRI fits a neurologic cause. I would suggest that you see a neurologist to investigate what might be producing the TIAs and receive appropriate treatment, if possible. For example, blockages of the carotid artery in your neck can produce TIAs and can be treated several ways. You must not avoid appropriate evaluation and treatment, even if it means leaving your animals with friends or some other solution. If you become disabled from your problem, let's say a stroke instead of the TIAs, you will be no help to your animals then!

Cardioversion vs. Ablation for AF

Reader: My son developed atrial fibrillation (AF) in September 2005. Despite Coreg, Digoxin, etc., he has not been able to revert to a normal sinus rhythm.
I know the risk of stroke is one in 1,000 when cardioversion is done. He asked his cardiologist about ablation and did not receive a positive answer. Since I was not present and I am unable to find the contraindications to ablation, I feel very concerned. Can you tell me why ablation would not be an option and if it is, indeed, less risky than cardioversion?

Dr. Zipes: Ablation is a procedure used to isolate or destroy tissue—in your son's case, the tissue in the top part of the heart called the atria and pulmonary veins that is causing the atrial fibrillation. Usually the procedure is done with catheters put into a blood vessel and then directed back to the heart under fluoroscopic guidance. The energy used to destroy the tissue is most commonly radiofrequency.

Radiofrequency catheter ablation of AF is an involved, relatively new procedure, with a complication rate in the range of one to two percent and a success rate for elimination of atrial fibrillation of about 60 to 90 percent, depending on the type of AF and experience of the physicians. It is definitely much more risky and involved than cardioversion, but it does offer the potential for eliminating the atrial fibrillation. Cardioversion is a procedure that stops the present episode of AF, with no impact on preventing recurrences.

My advice is for you to talk with an experienced electrophysiologist. You can find the name of one near you in the Web site of the Heart Rhythm Society.

Drug Therapy for AF

Reader: In October 2005, I was diagnosed with atrial fibrillation and put in the hospital for five days. My heart was monitored 24 hours a day, and I was given injections and medication until my clotting time reading hit "2."

Are all irregular heartbeats atrial fibrillation? And is it reasonable for doctors to expect a healthy 82-year-old man to maintain an INR of 1.7 to 2?

I am currently taking Flecainide and Warfarin. I have gone 15 months without any irregular episodes. Do you think it would be safe to discontinue the Warfarin?

Dr. Zipes: Atrial fibrillation is only one type of an irregular heartbeat, also called an arrhythmia. There are many types of arrhythmias, and they are diagnosed by interpreting the rhythm with the electrocardiogram. One of the risks associated with AF is the formation of blood clots in the heart, which can then dislodge and cause a stroke.

Coumadin, a blood thinner, is used to reduce greatly the risk of that happening. Maintaining an INR, which is a measure of the degree of anticoagulation, or blood thinning, in the range of 1.7-2.0 is a very reasonable approach in elderly patients. We want to achieve enough anticoagulation to prevent a stroke and not too much that might lead to bleeding complications. Flecainide is used to prevent further episodes of AF.

One of the problems with stopping the Coumadin is that—should the atrial fibrillation recur—the risk of a blood clot resumes. We know that a person's ability to tell whether the atrial fibrillation is present is not too good, and many episodes recur without the person's knowing it. Therefore it is often safer to keep taking the Coumadin rather than risk stopping it. If you strongly wish to stop the Coumadin, then your doctor needs to document carefully and objectively (using ECG recordings of your heart rhythm) that you are no longer having episodes of atrial fibrillation.

Needs Help for Nausea

Reader: In September 2005 I was hospitalized and diagnosed with congestive heart failure. I was nauseated in the hospital and also at home. I was also short of breath after coming home. Both problems worsened, and I had to go back to the hospital. They found that a blood clot in the left lung was causing the shortness of breath. An internist prescribed antibiotics for my nausea. It seemed to help a little but never took away the nausea. The problem is, I have to take seven pills every a.m. with food on a nauseated stomach.

I would be thankful for any help at all.

Dr. Zipes: Nausea can be a difficult problem to treat in some people because there are many causes. I can think of at least four in your case, in addition to the usual gastrointestinal causes.

First, nausea can be caused by congestion in your liver and stomach due to heart failure. Second, ischemia (lack of blood flow) to your bowel due to blockages in the arteries can cause nausea. Third, one or more of the medications you are taking can be the culprit. Finally, the clot that went to your lung can also go to the GI tract and cause it.

These problems need to be approached one at a time. First, your doctor needs to be sure that the heart failure is adequately treated. Clots are unlikely, since you are taking Coumadin. Blockages can be tested for. Finally, the medications need to be considered. Some, like potassium, are more likely than others to cause GI problems. The biggest culprits can be stopped, one at a time, with other medications substituted for them, to see if the nausea improves. If all fails, other antinausea medications can be tried.