Question Title: Palpitations from Heat, Pregnancy, and Thyroid

During episodes, she says that she sees black over her eyes and has sometimes actually fainted from it. She first experienced the symptoms after being in a Hot Tub 8 years ago. A year later she was diagnosed with hypothyroidism, had a growth on (or in) her thyroid, had a partial thyroidectomy, and was placed on a synthetic thyroid supplement. After the surgery and medication she was feeling better with no palpitations. When she became pregnant with our first child one year later, she began to have the palpitation and fainting symptoms again more frequently. A cardiologist placed her on a beta blocker during the remainder of the pregnancy; however, she did continue to have the same symptoms albeit less severe. After the pregnancy, I don't believe she experienced any more episodes. When she became pregnant with our second child the symptoms re-surfaced.

After the second pregnancy, she stopped taking the beta blockers. She has continued to have the palpitations, fainting symptoms about once every two or three months. During the pregnancies, she had seen cardiologists and other specialists and their feelins were that it was not a sever condition and most likely intensified from the stress and strain of pregnancy.

After having ready many of the palpitation related entries at this site, it seems that you typically will advise more caution to those that descibe dizziness and fainting. It has been 3 1/2 years since the birth of our youngest child and yet the fainting or near fainting still occurs. Also, she does not drink alcohol, smoke, and rarely has anything with caffiene.

Can you shed some light on our predicament?
Thank You for your help in advance.

Dear Sandor, thank you for your question. Your wife may be having an arrhythmia (abnormal fast or slow heart rhythm) or vasovagal syncope. An arrhythmia can cause fainting because the heart is unable to supply enough blood to the brain when it's beating too slow or too fast. Arrhythmias are diagnosed from cardiac monitors that can be worn for 1-2 days or for 2-4 weeks. I suspect that if she is having an arrhythmia, it would be a fast rhythm disturbance (called tachycardia) since she responded to beta blockers during her pregnancy. Vasovagal syncope occurs when the autonomic nervous system that supplies the heart is not working correctly. With vasovagal syncope, fear, pain, or sudden emotional changes can suddenly decrease the cardiac output and/or slow down the heart rate to cause syncope (fainting spells). I recommend that your wife have her thyroid hormone levels checked (since she may be receiving too much thyroid hormone supplementation) and that she see a cardiologist who specializes in rhythm disorders called an electrophysiologist. She may need to wear a long-term cardiac monitor and have a tilt table study to rule out vasovagal syncope. Also, it's good that she is avoiding alcohol, tobacco, and caffeine.

I hope you find this information useful. Information provided in the heart forum is for general purposes only. Only your physician can provide specific diagnoses and therapies. Please feel free to write back with additional questions. Good luck!

If you would like to make an appointment at the Cleveland Clinic Heart Center, please call 1-800-CCF-CARE or inquire online by using the Heart Center website at www.ccf.org/heartcenter. The Heart Center website contains a directory of the cardiology staff that can be used to select the physician best suited to address your cardiac problem.