How many cardiologists are currently in practice in the U.S.? Please list your source. Thanks!?

This is hard to answer precisely, because precise measures would require someone to conduct an expensive census. Which does not generally happen unless there is a good reason for it. But there r ways we can esitmate the number of practicing cardiologists, if u like.

According to the U.S. Department of Labour, as of 2004 there were approximately 567,000 physicians altogether. Those physicians fall into a variety of categories, with cardiologists lumped (unfortunately) into the 'other' category which makes up 33.9% of all physicians. (link 1)

We might be able to peel off another layer of the onion with the help of the American Board of Medical Specialties. These guys certify when a physician is 'qualified' to operate in the U.S., & they keep track of how many certifications they give out. One of the sub-specialties they have is for 'cardiovascular disease'. In the last ten years, 8240 of the 78409 certifications they've handed out have been in this specialty (link 2). Thus it is probably a fairly sound deduction that this reflects the percentage of cardiologists (or, at least doctors capable of acting as cardiologists) among all doctors. That calculates out to 10.5%.

If we bring back the statistic about total doctors from the Department of Labour, we find that there r approximately 60,000 practicing cardiologist in America. This is, however, a fairly loose estimate given the kinds of figures we're using. But it may be better than nothing! Hope that helps!