News

Atrial fibrillation: why it is important to monitor heart rate at rest and during activity

The American Academy of Family Physicians updated its guideline for the “Pharmacologic Management of Newly Detected Atrial Fibrillation”, emphasizing the importance of not just rhythm, but heart rate control to stabilize disease. This echoes the AHA/ACC/HRS treatment guidelines and reinforces the value of cardiac monitoring to guide the pharmacologic treatment of AF.

Clinical guidelines developed by leading cardiology groups both in the US and internationally, generally agree on the value of rate and rhythm control strategies, but in practice, there is a lack of consensus about when to use which approach, and which has the better impact on clinical outcomes in AF.

What Does the Science Say?

There is a great deal of debate in the medical community and opinions in the scientific literature vary. The Cochrane Collaboration in March published a protocol to conduct a systematic review and meta-analysis, which may impact clinical guidelines soon.

The AAFP guidelines in brief

For the pharmacologic management of Atrial Fibrillation, the AAFP strongly recommends rate control rather than rhythm control for the majority of patients who have atrial fibrillation. Lenient rate control (<110 beats per minute resting) is recommended over strict rate control (<80 beats per minute resting). Preferred options for rate-control therapy include nondihydropyridine calcium channel blockers and beta blockers. Rhythm control may be considered for certain patients based on patient symptoms, exercise tolerance, and patient preferences.

Using the Right Tools

The right arrhythmia monitoring device should measure not only heart rhythm, but heart rate during physical activity and at rest, and distinguish between various types of arrhythmia and normal sinus rhythm.

At Heart Rhythm Society Scientific Sessions 2017 we announced the addition of physical activity monitoring and reporting feature through a built-in accelerometer, to our complete cardiac monitoring solution – PocketECG. This means that in addition to providing the full disclosure ECG signal, labeling and classifying morphology for every heartbeat, and direct correlation of arrhythmia with symptoms, we are able to:

  • Differentiate between heart rate during physical activity and heart rate at rest
  • Provide information and analysis on the amount of time patients spend at different heart rates, separately for AF and sinus rhythm
  • Allow for correlation between arrhythmia, physical activity and symptoms
  • Monitor a patient for up to 30 days, which gives the physician enough time to set the medication dosage

Our daily reports include a series of histograms that present the amount of time patients remain at different heart rates. These histograms can be viewed as more advanced AF burden graphs that not only show how much time the patient spent in AF, but give the physician additional breakdown of the time in AF at various heart rates. The physicians can see the changes on a daily basis and observe the impact of a calcium blocker or beta blocker on the heart rate.

There is significant merit to both approaches to monitoring and treating atrial fibrillation patients. While researchers continue to work to validate the best approach for specific subsets of patients, we remain committed to providing diagnostics that allow clinicians to see and do more.

I highly encourage you to view a copy of our sample report, which includes rate and rhythm analysis.