This disease is so rare that regular primary care physicians and even many cardiologists don’t actually know about it, or know how to treat it! In medical school, student doctors are taught “Occam’s Razor” which says: “When you hear hoof beats, think horses, not zebras.” This stands for the proposition that the most common answer is usually the correct one. For example, if someone comes in to the office with shortness of breath, it is probably asthma or maybe they are out of shape. But SOMETIMES it is a rare disease! SOMETIMES it really IS a zebra! So we are the Zebras of the medical community. They are never really looking for us, so they often don’t think to look.
When I went back to my old doctor to tell him about my diagnosis, he was dumbfounded. He told me that he’d only ever read about PH in a footnote in a medical textbook in Medical School, and that in thirty years of practice he had never met anyone who had it! It is THAT rare.