What a cardiologist says about ECG+
In February 2026, cardiologist Dr. Anthony Pearson — who publishes the newsletter The Skeptical Cardiologist — came across ECG+ after a patient brought their Apple Watch recordings to him. He tried the app on those recordings, strips he had already read himself, and compared what it reported to the premature beats he could see with his own trained eye. Here's what he found, in his own words, including the caveats he raised.
What he found on premature-beat detection
Premature ventricular contractions (PVCs) and premature atrial contractions (PACs) are the extra or "skipped" beats that the Apple Watch ECG records but does not label. Dr. Pearson compared what ECG+ reported against the premature beats he had already identified himself in those recordings:
"In every recording I reviewed where PVCs were present, ECG+ had accurately identified the PVCs."— Dr. Anthony Pearson, The Skeptical Cardiologist, 21 February 2026
Dr. Pearson is known for taking a careful, evidence-first view of consumer health technology, so we think his assessment is worth reading in full. In the recordings he examined, he reported that the app's premature-beat detection matched his own.
How he described ECG+ alongside the Apple Watch ECG
The Apple Watch tells you whether a recording looks like sinus rhythm, AFib, or is inconclusive. It does not explain the individual abnormal beats inside the strip. Dr. Pearson noted that this is where ECG+ adds context — identifying those beats and what they may represent:
"ECG+ tells you what is likely causing those symptoms, useful information you can share with your doctor."
That reflects how ECG+ is intended to be used: not to self-diagnose, but to bring a clear, labelled record to an appointment rather than a vague description of a feeling. (More on that in what to ask your doctor about your Apple Watch ECG.)
The caveats he raised
Dr. Pearson was just as clear about the app's limitations, and we think they belong here alongside his praise:
Dr. Pearson's caveats
- QT/QTc figures call for some caution. On the app's interval measurements, he noted it is "unclear how reliable their measurements are."
- It's a paid subscription. Analysing the detected abnormalities sits behind a subscription.
- Most useful if you get premature beats. He suggested the app is most worthwhile for people whose recordings actually show PVCs or PACs.
- It is not a diagnosis. Throughout, his advice is to treat ECG+ findings as information to share with your own physician, not as a clinical verdict.
ECG+ is built to help you understand and share your Apple Watch ECG — not to replace your cardiologist. As Dr. Pearson cautions, single-lead QT/QTc figures should be confirmed by a clinician on a 12-lead ECG.
In summary
In his independent assessment, Dr. Pearson reported that ECG+ accurately identified the premature beats in the recordings he examined, and described its labelled output as useful information to share with a physician — while cautioning that its interval measurements still need clinical confirmation and that the app is most useful for people who get extra beats. We're grateful for his careful, independent look at it, and we'd encourage anyone interested to read his assessment in full.
Source: Anthony Pearson, MD — "Unlocking the Crucial Cardiac Information Hiding Within Your Smartwatch ECG Recordings," The Skeptical Cardiologist, 21 February 2026. Quotations are reproduced for commentary and review; the review is independent and was not commissioned by Heartworks. ECG+ is not a medical device and does not provide a diagnosis — always discuss findings with a qualified clinician. See our disclaimer.