@ling You are probably correct, and it sounds like you have one of the few “humble” pulmonologists. Humility is a neglected virtue these days. My husband was treated for asthma for years. Prior to going China in 2002, he had to have a chest X-ray. No asthma!!! He had sarcoid causing his symptoms. X-rays and CT scans may not show asthma , but they will pick up other visitors. His PCP had treated him for asthma for years! Now he sees a pulmonologist and his sarcoid is under control. My tachycardia started after my lungs became hyperinflated, my bronchiectasis had worsened, and I had RSV. I don’t like having tachycardia because it happens at weird times - like waking me up at night!! . I’m wearing a monitor right now and had a scan this morning- echo in a few weeks. Does your fast heartbeat annoy you?? I don’t like it one bit. Irene5