DEAR DR. ROACH: I had symptoms of lightheadedness, so my doctor ordered an EKG and sent me to a cardiologist. They did a heart monitor for a week and said I have inappropriate sinus tachycardia but that I don't need any treatment. I'm still having symptoms. What can I do? -- B.V.
ANSWER: Inappropriate sinus tachycardia is an uncommon diagnosis, most often seen in women in their 30s. The heart rate is fast ("tachycardia"), but on an EKG it appears normal, meaning it comes from the sino-atrial node, the natural pacemaker of the heart, hence "sinus." The average heart rate must be over 90 for 24 hours.