Ive had a few fainting spells,with spike to heart rate.ive been to a cardiologist today for ecg,echogram. all looks good.dr suspects pot syndrome or low bp.however resting in bed heart rate spiked to 150,no symptoms just headache.cause for concern?

Need more testing.: Ambulatory blood pressure monitoring sounds like a good idea. It could be that your HR is increasing rapidly as your blood pressure falls - compensatory, to keep your blood flowing, essentially. Episodes of low BP can be documented by ambulatory BP monitoring. HR can be monitored by event recorder. Both are symptom-relevant, too.