My first patient of the afternoon was a simple hypertension follow-up, or so I thought as I was walking into the room. She was a healthy 50-year-old woman with no medical problems other than her blood pressure, which was measured at 130/76 in the office. Her heart and lungs were normal, she had no chest pain or shortness of breath, and she was taking her medications without any problem. All simple enough. I complimented her on how she was doing, told her to continue her medications, and return in 6 months.
She put up her hand and said, “Wait a minute.”
Then she pulled out her smartphone. She tapped open an app, and handed it to me so I could look at a graph of her home blood pressures. The graph had all of her readings from the last 4 months, taken 2-3 times a day. It had automatically labeled each blood pressure in green, yellow, or red to indicate whether they were normal, higher than normal, or elevated, respectively.
Of course, the app creators had determined that a ‘green’ (normal) systolic pressure was less than 120 mm Hg. Values above that were yellow (higher than normal), until a systolic pressure of 130, at which point they became red (elevated). This is consistent with the most recent American Heart Association guidelines, but these guidelines have been the subject of a lot of controversy. There are many, including myself, who believe that the correct systolic pressure to define hypertension should be 140 for many patients, rather than 130. The app disagrees, and patients using the app see the app’s definition of hypertension every time they enter a blood pressure. In the case of my patient, since normal was indicated only by a systolic of less than 120 (which is a relatively rare event), I had to explain the difference between normal blood pressure and her blood pressure goal, and why the two were not the same.
Later that afternoon I was seeing a 60-year-old male who had electrical cardioversion of his atrial fibrillation 2 weeks prior to the visit. He had been sent home, as is usually the case, on an antiarrhythmic and an oral anticoagulant. He was feeling fine and had not noticed any palpitations, chest discomfort, or shortness of breath. I listened to his heart and lungs, which sounded normal, and I told him it sounded like he was doing well. Then he said, “I have an Apple watch.” I had a feeling I knew what was coming next.
He handed me his iPhone and asked me if I could review his rhythm strips. For those unacquainted with the new Apple watch, all he had to do to obtain those strips was open an EKG app and touch the crown of his watch with a finger from his other hand. This essentially made an electrical connection from his left to right arm, allowing the watch to generate a one-lead EKG tracing. The device then provides a computer-generated rhythm strip and sends that image and an interpretation of it to an iPhone, which is connected to the watch via Bluetooth. These results can then be shared or printed out as a pdf document.