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Whom do you believe? The patient or the ECG? Paul Dorian MD, MSc

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S1547-5271(15)00140-X http://dx.doi.org/10.1016/j.hrthm.2015.01.041 HRTHM6112

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Heart Rhythm

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Cite this article as: Paul Dorian MD, MSc, Whom do you believe? The patient or the ECG?, Heart Rhythm, http://dx.doi.org/10.1016/j.hrthm.2015.01.041 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting galley proof before it is published in its final citable form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Whom do you believe? The patient or the ECG?

Paul Dorian, MD, MSc

Keenan Research Centre, Li Ka Shing Knowledge Institute, St Michael’s Hospital, University of Toronto, Toronto, ON, Canada

Funding: None Conflict of Interests: None

Address Correspondence to: Paul Dorian, MD Division of Cardiology, St. Michael’s Hospital 30 Bond Street, Room 6-050 Toronto, Ontario, Canada, M5B 1W8 Phone: (416) 864-5104, Fax: (416) 864-5104 [email protected]

Word Count: 1500

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Who do you believe? The patient or the ECG? Paul Dorian, MD, MSc

The primary goal of physicians and caregivers in managing patients with Atrial Fibrillation is to improve their quality of life, and to prevent stroke. Since there is no proof that any rhythm control treatment reduces morbidity or mortality, reducing symptoms and improving quality of life is paramount in the treatment of AF.

It may seem intuitive to believe that symptoms from AF are closely related to the presence of AF on ECG recordings. However, prior studies, especially after AF ablation, have highlighted the notion that many episodes of AF are asymptomatic; some patients have AF but are never symptomatic, and in others some episodes are perceived and others entirely subjectively inapparent1.

Garimella and colleagues, in this issue of the Journal2 provide an important service to the arrhythmia community by detailing the relationship between patients’ perceptions of the frequency and duration of AF episodes and the “burden” of ECG recorded episodes of atrial fibrillation.

Patient perceptions were measured as the patient estimated frequency and duration of symptoms related to AF using a part the AFSS scale, and objective AF “burden” was measured using continuous ECG monitoring in the week following the questionnaire completion.

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Patients were labeled [arbitrarily] as "under estimators" or "over estimators". The primary conclusion is that some patients are "over" or "under" estimators, and that the patients who do not accurately estimate their burden of AF tend to be more often older, women, and have persistent AF. Patients with mood disorders are more likely to over estimate AF burden.

This study serves as an important reminder that one cannot necessarily equate patient reports of the frequency or duration of symptoms with actual ECG documented rhythms. Therefore, treating patients only on the basis of their reported subjective episodes of AF may lead to inappropriately treating symptoms that are not related to AF. The converse, i.e. inappropriately treating documented AF that the patient is unaware of, also applies, in that there is no good reason to treat most asymptomatic atrial fibrillation, even if it is documented on ECG3.

Limitations of the study by Garimella et al include the differing time periods for the subjective vs the objective measurements, such that the frequency and average duration of symptoms were aggregated over an unspecified time period prior to the clinic visit, whereas the ECG monitoring took place after the clinic visit. The temporal pattern of AF of course can change over time, and patient recollection of their symptoms over the prior months may be imperfect.

It is important to note that subjective frequency and duration, but not symptom severity or quality of life (QOL) were measured in this study. In prior studies, frequency or duration of AF was not correlated with overall quality of life, as measured by caregivers’ global estimate. 4 On the other hand, symptom scores in patients with AF correlate closely with overall AF related

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quality of life, when QOL is considered to encompass symptoms, activities, treatment concerns, and treatment satisfaction.4,5

Kahneman and Riedelmeier,6 have performed important studies to explore the difference between "lived experience" and "remembered experience". Both for medical procedures, such as colonoscopy, and for everyday life experiences, symptoms or feelings “in the moment” may be very different from the subsequent recollection of symptoms or feelings after the fact. Since patients act on AF symptoms at the moment they occur, for example in seeking immediate or urgent medical care, delayed recollections of symptoms, as in this study, may give an incomplete picture of the quality of life impact of atrial fibrillation as an illness.

The recommendation to use heart rhythm monitoring in order to better target therapy should be done with an understanding of the very serious limitations of this approach. For example, in patients with persistent or permanent (“accepted”) atrial fibrillation, monitoring in the absence of symptoms is not helpful, since patients would not require treatment regardless of what the ambulatory ECG demonstrates. In an asymptomatic patient, resting heart rates less than 110/min by European, 100/min by Canadian, and 80/min by US guidelines do not require any change in treatment. On the other hand, if patients are symptomatic, an "instantaneous symptom/rhythm correlation" seems useful, particularly in patients with exercise-induced symptoms. If the heart rate during symptoms is very high, it seems reasonable to intensify rate control or consider rhythm control for its symptomatic benefit. Conversely, if symptoms are correlated with rates that are similar to prevailing rates through most of the day, changing AF management may have

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little impact on symptoms. Once this relation is established, there seems little reason to repeatedly perform monitoring for this purpose.

For paroxysmal AF, the considerations are different, and more straightforward. The recording of symptoms during sinus rhythm, using patient activated event monitors in preference to continuous ECG recording, suggests that it is of little to no value to treat the Atrial Fibrillation, since symptoms are likely to be due to other cardio respiratory problems, or at least not related to AF per se. If symptoms sometimes correspond to AF and sometimes not, patients need to be aware that only some of the symptoms are likely to respond, even with effective rhythm or rate control.

Such patients are not rare, as can be seen in figure 1 of the paper by Garimella and colleagues; there are many patients with substantial AF burden by perception, whereas the AF burden by monitor is nil or minimal. This apparent disconnect may be due to reduction in AF burden between the period prior to the monitoring and the monitoring itself, or the patient ascribing AF to symptoms due to other causes. In this situation, it is of course not useful to add or change rhythm control therapies, since this is unlikely to change symptom burden. It is also possible that the symptoms in these cases are due to adverse effects of therapy. In such patients, reassurance and education may be the primary treatment modality.

If the symptoms of AF occur simultaneously with AF on event monitoring, the severity of symptoms and their effect on overall life quality can be used to weigh the risks and benefits of starting or intensifying rate or rhythm control. The mere ability for a patient to distinguish AF

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from sinus rhythm does not necessarily imply that specific treatment is required, since some patients tolerate AF symptoms well and may not wish to take on the risks and inconvenience or cost of therapy, particularly rhythm control therapy.

An additional consideration in relating ECG detected arrhythmias to symptoms and to management, is the complicated relationship between overall patient well-being and symptoms specific to AF.7 Just as one cannot assume that a reduction in AF burden will lead to an improvement in symptoms attributable to AF, changes in AF symptoms do not necessarily lead to a commensurate change an overall well-being. Concurrent illnesses, anxiety or depression, and adverse effects of therapies will have an important influence on the overall outcome of treatment.

Based on these considerations, it does not seem useful to record the AF burden, or document obsessively AF episodes by ECG (or using advanced technologies such as smartphone applications to record and tabulate AF), once the connection between AF and symptoms in a particular patient have been established.

The work by Garimella et al reminds us that correlating symptoms to ECG abnormalities is important; however, the integrated effect of subjective symptoms and the treatment on overall well-being is the single most important measure of treatment benefit.

Acknowledgements: I am grateful to Dr. Paul Angaran and Dr. Iqwal Mangat for their review and comments and to Kim Dawdy for her help in the preparation of this manuscript. 6

REFERENCES

1) Verma A, Champagne J, Sapp J, Essebag V, Novak P, Skanes A, Morillo CA, Khaykin Y, Birnie D. Discerning the incidence of symptomatic and asymptomatic episodes of atrial fibrillation before and after catheter ablation (DISCERN AF): a prospective, multicenter study. JAMA Intern Med 201328;173:149-56.

2) Garimella RS, Chung EH, Mounsey JP, Schwartz JD, Pursell I, Gehi AK. Accuracy of patient perception of their prevailing rhythm: a comparative analysis of monitor data and questionnaire responses in patients with atrial fibrillation. Heart Rhythm 2015 Jan 13. [Epub ahead of print]

3) Gillis AM, Verma A, Talajic M, Nattel S, Dorian P, CCS Atrial Fibrillation Guidelines Committee. Canadian Cardiovascular Society atrial fibrillation guidelines 2010: rate and rhythm management. Can J Cardiol 2011;27:47-59.

4) Dorian P, Guerra PG, Kerr CR, O'Donnell SS, Crystal E, Gillis AM, Mitchell LB, Roy D, Skanes AC, Rose MS, Wyse DG. Validation of a new simple scale to measure symptoms in atrial fibrillation: the Canadian Cardiovascular Society Severity in Atrial Fibrillation scale. Circ Arrhythm Electrophysiol. 2009;2:218-24.

5) Spertus J, Dorian P, Bubien R, Lewis S, Godejohn D, Reynolds MR, Lakkireddy DR, Wimmer AP, Bhandari A, Burk C. Development and validation of the Atrial Fibrillation 7

Effect on QualiTy-of-Life (AFEQT) Questionnaire in patients with atrial fibrillation. Circ Arrhythm Electrophysiol 201;4:15-25.

6) Redelmeier DA, Katz J, Kahneman D. Memories of colonoscopy: a randomized trial. Pain 2003;104:187-94.

7) Dorian P, Burk C, Mullin CM, Bubien R, Godejohn D, Reynolds MR, Lakkireddy DR, Wimmer AP, Bhandari A, Spertus J. Interpreting changes in quality of life in atrial fibrillation: how much change is meaningful? Am Heart J 2013;166:381-387.

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Whom do you believe? The patient or the ECG?

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