{
  "release_id": "f4600233112e1c27",
  "id": "cardio:guide-watch-irregular-rhythm",
  "owner": "cardio",
  "kind": "patient_guide",
  "slug": "watch-irregular-rhythm",
  "name": "My watch flagged an irregular rhythm",
  "aliases": [],
  "atlases": [
    "cardio"
  ],
  "summary_plain": "What FDA's 2018 summary says one watch feature is for, what studies of watch alerts measured, how the sources describe checking for atrial fibrillation, and questions to ask a clinician.",
  "summary_technical": "A static guide written from an FDA summary, a study abstract and registry entry, a task force statement and four US government health pages. It gives no advice for one reader.",
  "editorial_state": "draft",
  "last_substantive_edit": "2026-10-15",
  "last_evidence_check": "2026-10-15",
  "next_review_due": "2027-04-15",
  "identifiers": [],
  "navigation": {
    "cardio": {
      "condition-area": [
        "arrhythmias"
      ]
    }
  },
  "payload": {
    "purpose": "explainer",
    "audience": "Adults whose smartwatch has flagged an irregular rhythm, and the people with them",
    "about": [
      "cardio:apple-irregular-rhythm-notification",
      "cardio:wearable-rhythm-detection",
      "cardio:apple-heart-study",
      "cardio:guideline-uspstf-2022-af-screening",
      "cardio:atrial-fibrillation"
    ],
    "reading_grade_target": 10,
    "scope_note": "Written from an FDA summary, a study abstract, a registry entry, a task force statement and four US government health pages. The FDA summary covers one 2018 authorization, for Apple's feature. Other watches and later versions of the feature are not covered. The guide describes what the sources say. It gives no advice for one person.",
    "warning_blocks": [
      {
        "heading": "From the MedlinePlus arrhythmia page",
        "signs": [
          {
            "id": "sign-chest",
            "text": "MedlinePlus lists chest pain among the symptoms of an arrhythmia.",
            "cites": [
              {
                "snapshot_id": "cardio:medlineplus-arrhythmia-2026-10-14",
                "locator": "Summary, What are the symptoms of an arrhythmia?, list item 3"
              }
            ]
          },
          {
            "id": "sign-breath",
            "text": "MedlinePlus also lists shortness of breath among the symptoms of an arrhythmia.",
            "cites": [
              {
                "snapshot_id": "cardio:medlineplus-arrhythmia-2026-10-14",
                "locator": "Summary, What are the symptoms of an arrhythmia?, list item 5"
              }
            ]
          }
        ],
        "act_now": [
          {
            "snapshot_id": "cardio:medlineplus-arrhythmia-2026-10-14",
            "locator": "Summary, What are the symptoms of an arrhythmia?, last sentence",
            "words": "Seek emergency medical care if you have chest pain, shortness of breath, or think you are having a heart attack."
          }
        ]
      }
    ],
    "sections": [
      {
        "heading": "What FDA's 2018 summary says about the feature",
        "statements": [
          {
            "id": "fda-grant",
            "text": "FDA granted a De Novo request from Apple for software that sends irregular rhythm notifications on the Apple Watch, with a decision date of September 11, 2018.",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Conclusion"
              },
              {
                "snapshot_id": "cardio:openfda-510k-den180042-2026-10-14",
                "locator": "results[0].decision_date"
              },
              {
                "snapshot_id": "cardio:openfda-510k-den180042-2026-10-14",
                "locator": "results[0].applicant"
              }
            ]
          },
          {
            "id": "fda-what",
            "text": "The summary says the Apple Watch software studies pulse data and sends a notification, here called an alert, when it spots an irregular rhythm that may point to atrial fibrillation (AFib).",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Indications for use, sentence 1"
              },
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Indications for use, sentence 2"
              }
            ]
          },
          {
            "id": "fda-otc",
            "text": "It labels the feature as over-the-counter.",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Indications for use, sentence 3"
              }
            ]
          },
          {
            "id": "fda-bg",
            "text": "It calls the feature a tool that screens in the background and says a user cannot start a check.",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Device description, paragraph 1"
              }
            ]
          },
          {
            "id": "fda-still",
            "text": "It says the data are captured only while the wearer is still.",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Indications for use, sentence 5"
              }
            ]
          },
          {
            "id": "fda-threshold",
            "text": "In this 2018 description, an alert appears when five of six readings in a row, within 48 hours, are classified as irregular.",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Device description, Irregular Rhythm Notification Feature, sentence 2"
              }
            ]
          },
          {
            "id": "fda-seek",
            "text": "The summary says the alert also encourages users who were not previously diagnosed with AFib to seek medical care.",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Device description, Irregular Rhythm Notification Feature, last sentence"
              }
            ]
          },
          {
            "id": "fda-history",
            "text": "It says the phone app shows a record of past AFib alerts and a list of when the irregular readings behind each one were taken.",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Device description, iPhone App, sentence 3"
              },
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Device description, iPhone App, sentence 4"
              }
            ]
          },
          {
            "id": "fda-ages",
            "text": "It says the feature was not tested in people under 22, and that it is not meant for them or for people previously diagnosed with AFib.",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Indications for use, paragraph 2, sentence 1"
              },
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Indications for use, paragraph 2, sentence 2"
              }
            ]
          },
          {
            "id": "fda-screen",
            "text": "It adds that the feature, together with a person's risk factors, can help inform the decision about AFib screening.",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Indications for use, sentence 6"
              }
            ]
          },
          {
            "id": "fda-nodx",
            "text": "It says the feature is not meant to replace usual diagnosis or treatment, and not meant to guide clinical care.",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Indications for use, sentence 7"
              },
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Device description, paragraph 2"
              }
            ]
          },
          {
            "id": "fda-type",
            "text": "FDA's description of this type of device adds that such a device is not meant to diagnose.",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Regulatory information, device type"
              }
            ]
          }
        ]
      },
      {
        "heading": "What the 2018 summary says an alert cannot tell",
        "statements": [
          {
            "id": "lim-possible",
            "text": "The labeling text in the summary calls an alert a possible finding, not a full diagnosis of heart conditions.",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Limitations, notifications paragraph, sentence 1"
              }
            ]
          },
          {
            "id": "lim-review",
            "text": "That text also says a medical professional should review all alerts.",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Limitations, notifications paragraph, sentence 2"
              }
            ]
          },
          {
            "id": "lim-ecg",
            "text": "The summary also says the labeling states that an AFib diagnosis should still rest on confirmation by ECG.",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Benefit/risk determination, paragraph 2"
              }
            ]
          },
          {
            "id": "lim-not-every",
            "text": "The summary says the feature is not meant to give an alert for every irregular episode, and a missing alert is not meant to show that no disease is present.",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Indications for use, sentence 4"
              }
            ]
          },
          {
            "id": "lim-continuous",
            "text": "The labeling text says the feature does not look for AFib all the time, so it cannot find every instance and some people with AFib may get no alert.",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Limitations, paragraph 2, sentence 1"
              },
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Limitations, paragraph 2, sentence 2"
              }
            ]
          },
          {
            "id": "lim-attack",
            "text": "The labeling text also says the feature is unable to detect a heart attack.",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Limitations, paragraph 1"
              }
            ]
          },
          {
            "id": "lim-signal",
            "text": "The labeling text lists motion, hand and finger movement, dark wrist tattoos, and blood flow to the skin, which cold can reduce, among factors that can affect the pulse measurement.",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Limitations, paragraph 4, sentence 1"
              },
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Limitations, paragraph 4, sentence 2"
              }
            ]
          },
          {
            "id": "lim-risk",
            "text": "The summary names a probable risk that users will misread the output and ignore acute symptoms, such as those of a heart attack.",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Benefit/risk determination, paragraph 3"
              }
            ]
          },
          {
            "id": "lim-risk2",
            "text": "It also says users may take the output as permission to avoid following a treatment already prescribed for a long-term heart condition.",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Benefit/risk determination, paragraph 3"
              }
            ]
          }
        ]
      },
      {
        "heading": "What studies of watch alerts measured",
        "statements": [
          {
            "id": "ahs-app",
            "text": "The Apple Heart Study used its own research app, and this guide's sources do not say how that app, or the study, relates to the clinical study in the FDA summary.",
            "cites": [
              {
                "snapshot_id": "cardio:ctgov-nct03335800-2026-10-14",
                "locator": "protocolSection.armsInterventionsModule.armGroups[0].label"
              }
            ]
          },
          {
            "id": "ahs-who",
            "text": "The Apple Heart Study recruited 419,297 people who reported having no atrial fibrillation, and a smartwatch program looked for an irregular pulse.",
            "cites": [
              {
                "snapshot_id": "cardio:pubmed-31722151-2026-10-14",
                "locator": "Abstract, RESULTS, sentence 1"
              },
              {
                "snapshot_id": "cardio:pubmed-31722151-2026-10-14",
                "locator": "Abstract, METHODS, sentence 1"
              },
              {
                "snapshot_id": "cardio:pubmed-31722151-2026-10-14",
                "locator": "Abstract, METHODS, sentence 2, fragment 1 of 2"
              }
            ]
          },
          {
            "id": "ahs-alerts",
            "text": "Over a median of 117 days of monitoring, 2161 people (0.52%) received a notification of an irregular pulse from the study's app.",
            "cites": [
              {
                "snapshot_id": "cardio:pubmed-31722151-2026-10-14",
                "locator": "Abstract, RESULTS, sentence 2"
              },
              {
                "claim": "cardio:claim-apple-heart-study-alerts"
              }
            ]
          },
          {
            "id": "ahs-patch",
            "text": "Of the 450 notified people who returned usable ECG patch data, 34% (97.5% confidence interval, 29 to 39) had atrial fibrillation on the patch, which was applied on average 13 days after the notification.",
            "cites": [
              {
                "snapshot_id": "cardio:pubmed-31722151-2026-10-14",
                "locator": "Abstract, RESULTS, sentence 3, fragment 1 of 3"
              },
              {
                "snapshot_id": "cardio:pubmed-31722151-2026-10-14",
                "locator": "Abstract, RESULTS, sentence 3, fragment 2 of 3"
              },
              {
                "claim": "cardio:claim-apple-heart-study-alerts"
              }
            ]
          },
          {
            "id": "ahs-contact",
            "text": "Of 1376 people who got a notification from the study's app and returned a 90-day survey, 57% contacted health care providers outside the study.",
            "cites": [
              {
                "snapshot_id": "cardio:pubmed-31722151-2026-10-14",
                "locator": "Abstract, RESULTS, sentence 5"
              }
            ]
          },
          {
            "id": "ahs-group",
            "text": "The study's registry entry lists a single study group.",
            "cites": [
              {
                "snapshot_id": "cardio:ctgov-nct03335800-2026-10-14",
                "locator": "protocolSection.designModule.designInfo.interventionModel"
              }
            ]
          },
          {
            "id": "ahs-outcomes",
            "text": "Its registry entry lists four outcomes, about atrial fibrillation of more than 30 seconds, confirmed atrial fibrillation, agreement with the app's notification, and contact with a health care provider.",
            "cites": [
              {
                "snapshot_id": "cardio:ctgov-nct03335800-2026-10-14",
                "locator": "protocolSection.outcomesModule.primaryOutcomes[0].measure"
              },
              {
                "snapshot_id": "cardio:ctgov-nct03335800-2026-10-14",
                "locator": "protocolSection.outcomesModule.primaryOutcomes[1].measure"
              },
              {
                "snapshot_id": "cardio:ctgov-nct03335800-2026-10-14",
                "locator": "protocolSection.outcomesModule.secondaryOutcomes[0].measure"
              },
              {
                "snapshot_id": "cardio:ctgov-nct03335800-2026-10-14",
                "locator": "protocolSection.outcomesModule.secondaryOutcomes[1].measure"
              }
            ]
          },
          {
            "id": "ahs-nostroke",
            "text": "None of the four outcomes is about strokes.",
            "cites": [
              {
                "snapshot_id": "cardio:ctgov-nct03335800-2026-10-14",
                "locator": "protocolSection.outcomesModule.primaryOutcomes[0].measure"
              },
              {
                "snapshot_id": "cardio:ctgov-nct03335800-2026-10-14",
                "locator": "protocolSection.outcomesModule.primaryOutcomes[1].measure"
              },
              {
                "snapshot_id": "cardio:ctgov-nct03335800-2026-10-14",
                "locator": "protocolSection.outcomesModule.secondaryOutcomes[0].measure"
              },
              {
                "snapshot_id": "cardio:ctgov-nct03335800-2026-10-14",
                "locator": "protocolSection.outcomesModule.secondaryOutcomes[1].measure"
              }
            ]
          },
          {
            "id": "fda-miss",
            "text": "In a sub-study described in the FDA summary, the result for single irregular readings did not reach the accuracy goal set before the study.",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Summary of clinical study, performance results"
              }
            ]
          },
          {
            "id": "fda-supportive",
            "text": "FDA still judged the secondary and further analyses to support the feature's effectiveness in detecting AFib.",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Summary of clinical study, secondary analyses"
              }
            ]
          },
          {
            "id": "fda-posthoc",
            "text": "In an analysis added after the study's plan, of 226 people who already had notifications from the feature, AFib was documented on later 7-day patch monitoring in 41.6% (95% CI, 35.1 to 48.3).",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Summary of clinical study, post hoc analysis"
              }
            ]
          },
          {
            "id": "fda-benefit",
            "text": "FDA wrote that this feature is not meant to diagnose AFib but is an accessible tool for finding people who would probably gain from more AFib screening using ECG-based methods.",
            "cites": [
              {
                "snapshot_id": "cardio:fda-denovo-den180042-summary-2026-10-15",
                "locator": "Benefit/risk determination, paragraph 1"
              }
            ]
          }
        ]
      },
      {
        "heading": "How the sources describe checking for atrial fibrillation",
        "statements": [
          {
            "id": "dx-silent",
            "text": "MedlinePlus says some people who have AFib have no symptoms and do not know they have it.",
            "cites": [
              {
                "snapshot_id": "cardio:medlineplus-atrial-fibrillation-2026-10-14",
                "locator": "Summary, What are the symptoms of atrial fibrillation (AFib)?, sentence 1"
              }
            ]
          },
          {
            "id": "dx-brief",
            "text": "MedlinePlus says AFib may happen in brief episodes, or it may be a permanent condition.",
            "cites": [
              {
                "snapshot_id": "cardio:medlineplus-atrial-fibrillation-2026-10-14",
                "locator": "Summary, What is atrial fibrillation (AFib)?, para 3"
              }
            ]
          },
          {
            "id": "dx-nhlbi",
            "text": "NHLBI says a provider reaches a diagnosis of atrial fibrillation using the patient's history and a physical exam, along with an EKG and, in some cases, other tests.",
            "cites": [
              {
                "snapshot_id": "cardio:nhlbi-af-diagnosis-2026-10-15",
                "locator": "Page body, introduction"
              }
            ]
          },
          {
            "id": "dx-ekg",
            "text": "NHLBI says an EKG records the electrical activity of the heart.",
            "cites": [
              {
                "snapshot_id": "cardio:nhlbi-af-diagnosis-2026-10-15",
                "locator": "Page body, Diagnostic tests, bullet 1"
              }
            ]
          },
          {
            "id": "dx-monitors",
            "text": "NHLBI says Holter and event monitors are portable EKG devices that record over long periods of everyday activity.",
            "cites": [
              {
                "snapshot_id": "cardio:nhlbi-af-diagnosis-2026-10-15",
                "locator": "Page body, Other tests, Holter and event monitors"
              }
            ]
          },
          {
            "id": "dx-monitors2",
            "text": "It says they can help explain symptoms such as palpitations or dizziness that occur away from the provider's office.",
            "cites": [
              {
                "snapshot_id": "cardio:nhlbi-af-diagnosis-2026-10-15",
                "locator": "Page body, Other tests, Holter and event monitors"
              }
            ]
          },
          {
            "id": "dx-devices",
            "text": "NHLBI also says that several devices can now detect and record heart rhythm in a way similar to an EKG, and that readings from these devices may be emailed to a provider.",
            "cites": [
              {
                "snapshot_id": "cardio:nhlbi-af-diagnosis-2026-10-15",
                "locator": "Page body, Screening methods, bullet 2"
              }
            ]
          },
          {
            "id": "dx-mlp-history",
            "text": "MedlinePlus says a provider will ask about medical history, including symptoms, lifestyle and other health conditions, and about relatives who have or had AFib.",
            "cites": [
              {
                "snapshot_id": "cardio:medlineplus-atrial-fibrillation-2026-10-14",
                "locator": "Summary, How is atrial fibrillation (AFib) diagnosed?, list item 1"
              },
              {
                "snapshot_id": "cardio:medlineplus-atrial-fibrillation-2026-10-14",
                "locator": "Summary, How is atrial fibrillation (AFib) diagnosed?, list item 2"
              }
            ]
          },
          {
            "id": "dx-mlp-tests",
            "text": "MedlinePlus says a provider will likely order heart tests such as an electrocardiogram (“also called an EKG or ECG”) and an echocardiogram, and may ask the patient to wear a heart monitor.",
            "cites": [
              {
                "snapshot_id": "cardio:medlineplus-atrial-fibrillation-2026-10-14",
                "locator": "Summary, How is atrial fibrillation (AFib) diagnosed?, list item 5"
              },
              {
                "snapshot_id": "cardio:medlineplus-atrial-fibrillation-2026-10-14",
                "locator": "Summary, How is atrial fibrillation (AFib) diagnosed?, list item 6"
              }
            ]
          }
        ]
      },
      {
        "heading": "What MedlinePlus lists as symptoms of an arrhythmia",
        "statements": [
          {
            "id": "sym-list",
            "text": "MedlinePlus says symptoms of arrhythmias in general can include a fast or slow heartbeat; skipping, fluttering or pounding heartbeats; chest pain or discomfort; dizziness or fainting; shortness of breath; sweating; and tiredness or weakness.",
            "cites": [
              {
                "snapshot_id": "cardio:medlineplus-arrhythmia-2026-10-14",
                "locator": "Summary, What are the symptoms of an arrhythmia?, lead-in"
              },
              {
                "snapshot_id": "cardio:medlineplus-arrhythmia-2026-10-14",
                "locator": "Summary, What are the symptoms of an arrhythmia?, list item 1"
              },
              {
                "snapshot_id": "cardio:medlineplus-arrhythmia-2026-10-14",
                "locator": "Summary, What are the symptoms of an arrhythmia?, list item 2"
              },
              {
                "snapshot_id": "cardio:medlineplus-arrhythmia-2026-10-14",
                "locator": "Summary, What are the symptoms of an arrhythmia?, list item 3"
              },
              {
                "snapshot_id": "cardio:medlineplus-arrhythmia-2026-10-14",
                "locator": "Summary, What are the symptoms of an arrhythmia?, list item 4"
              },
              {
                "snapshot_id": "cardio:medlineplus-arrhythmia-2026-10-14",
                "locator": "Summary, What are the symptoms of an arrhythmia?, list item 5"
              },
              {
                "snapshot_id": "cardio:medlineplus-arrhythmia-2026-10-14",
                "locator": "Summary, What are the symptoms of an arrhythmia?, list item 6"
              },
              {
                "snapshot_id": "cardio:medlineplus-arrhythmia-2026-10-14",
                "locator": "Summary, What are the symptoms of an arrhythmia?, list item 7"
              }
            ]
          }
        ]
      },
      {
        "heading": "What a national task force said about screening",
        "statements": [
          {
            "id": "us-1",
            "text": "In 2022, the USPSTF found the evidence too limited to judge whether screening for atrial fibrillation does more good than harm, which it calls an I statement.",
            "cites": [
              {
                "claim": "cardio:claim-uspstf-2022-af-screening-i"
              }
            ]
          },
          {
            "id": "us-2",
            "text": "The statement covers adults 50 or older with no atrial fibrillation diagnosis or symptoms and no earlier stroke or transient ischemic attack.",
            "cites": [
              {
                "claim": "cardio:claim-uspstf-2022-af-screening-i"
              }
            ]
          }
        ]
      }
    ],
    "checklists": [
      {
        "heading": "What the sources say a provider asks about or uses",
        "items": [
          {
            "id": "chk-log",
            "text": "A record of how often and when symptoms occur, what is felt and whether this changes over time, which NHLBI calls important clues for diagnosis.",
            "cites": [
              {
                "snapshot_id": "cardio:nhlbi-af-symptoms-2026-10-15",
                "locator": "Page body, after the symptom list, sentence 1"
              },
              {
                "snapshot_id": "cardio:nhlbi-af-symptoms-2026-10-15",
                "locator": "Page body, after the symptom list, sentence 2"
              }
            ]
          },
          {
            "id": "chk-device",
            "text": "Heart rhythm readings from a device, which NHLBI says may be emailed to a provider.",
            "cites": [
              {
                "snapshot_id": "cardio:nhlbi-af-diagnosis-2026-10-15",
                "locator": "Page body, Screening methods, bullet 2"
              }
            ]
          },
          {
            "id": "chk-history",
            "text": "Medical history, including symptoms, lifestyle and other health conditions, which MedlinePlus says a provider will ask about.",
            "cites": [
              {
                "snapshot_id": "cardio:medlineplus-atrial-fibrillation-2026-10-14",
                "locator": "Summary, How is atrial fibrillation (AFib) diagnosed?, list item 1"
              }
            ]
          },
          {
            "id": "chk-family",
            "text": "Family history of AFib, which MedlinePlus says a provider will ask about.",
            "cites": [
              {
                "snapshot_id": "cardio:medlineplus-atrial-fibrillation-2026-10-14",
                "locator": "Summary, How is atrial fibrillation (AFib) diagnosed?, list item 2"
              }
            ]
          }
        ]
      }
    ],
    "questions": [
      {
        "text": "Does my watch alert point to atrial fibrillation, and which test would confirm it?",
        "grounded_in": [
          "lim-possible",
          "lim-ecg",
          "dx-nhlbi"
        ]
      },
      {
        "text": "The FDA summary says the feature is not meant for people under 22 or people already diagnosed with AFib; does that apply to me?",
        "grounded_in": [
          "fda-ages"
        ]
      },
      {
        "text": "If my watch gives no alert, does that say anything about my heart?",
        "grounded_in": [
          "lim-not-every",
          "lim-continuous"
        ]
      },
      {
        "text": "Would an EKG, a heart monitor or another test help sort out what the alert found?",
        "grounded_in": [
          "dx-ekg",
          "dx-monitors",
          "dx-monitors2",
          "dx-mlp-tests"
        ]
      },
      {
        "text": "Would the history of alerts on my phone, or a record of my symptoms, help you?",
        "grounded_in": [
          "fda-history",
          "chk-log"
        ]
      },
      {
        "text": "Can readings from my device be sent to you, and in what form?",
        "grounded_in": [
          "dx-devices",
          "chk-device"
        ]
      },
      {
        "text": "Do the results of the Apple Heart Study apply to someone like me?",
        "grounded_in": [
          "ahs-who",
          "ahs-patch",
          "ahs-app"
        ]
      },
      {
        "text": "Does the 2022 task force statement on screening change anything for me?",
        "grounded_in": [
          "us-1",
          "us-2"
        ]
      }
    ]
  },
  "content_digest": "ae13f7bcd486ce489bdca88e333dd7d10e3cda8d83059aee1293ccd69348eefe",
  "review": {
    "content_digest": "ae13f7bcd486ce489bdca88e333dd7d10e3cda8d83059aee1293ccd69348eefe",
    "current": [],
    "conflicting": [],
    "stale": [],
    "inactive": []
  },
  "claims": [],
  "decisions": [],
  "milestones": [],
  "relationships": {
    "outgoing": [],
    "incoming": []
  },
  "page_path": "guides/watch-irregular-rhythm/",
  "context_path": "api/v1/context/cardio--guide-watch-irregular-rhythm.md"
}