Respiratory Function Assessment in Patients With Atrial Fibrillation: A Needed Extension of Combined Comorbidity Management?

Atrial fibrillation (AF) is often associated with multiple traditional comorbidities such as hypertension, heart failure, diabetes, and obesity.1Pathak R.K. Mahajan R. Lau D.H. Sanders P. The implications of obesity for cardiac arrhythmia mechanisms and management.Can J Cardiol. 2015; 31: 203-210Abstract Full Text Full Text PDF PubMed Scopus (72) Google Scholar Besides sleep apnea,2Linz D. McEvoy R.D. Cowie M.R. et al.Associations of obstructive sleep apnea with atrial fibrillation and continuous positive airway pressure treatment: a review.JAMA Cardiol. 2018; 3: 532-540Crossref PubMed Scopus (194) Google Scholar chronic obstructive pulmonary disease (COPD) is another emerging respiratory risk factor for AF. COPD is associated with increased AF incidence, AF progression, and reduced treatment response to rhythm control strategies such as cardioversion, antiarrhythmic drug treatment, and catheter ablation.3Simons S.O. Elliott A. Sastry M. et al.Chronic obstructive pulmonary disease and atrial fibrillation: an interdisciplinary perspective.Eur Heart J. 2021; 42: 532-540Crossref PubMed Scopus (29) Google Scholar In addition, COPD is associated with higher symptom burden and worse quality of life. COPD is also associated with increased hospital admissions and all-cause mortality in AF patients.4Warming P.E. Garcia R. Hansen C.J. et al.The association of temporal sequence in atrial fibrillation and chronic obstructive pulmonary disease diagnosis and mortality risk.Eur Heart J Qual Care Clin Outcomes. 2023; 9: 128-134Crossref PubMed Google Scholar Importantly, this liaison between AF and COPD is not merely the result of shared risk factors; there is increasing evidence that direct COPD-related mechanisms contribute to AF onset and AF progression. Gas exchange abnormalities (ie, hypoxemia and hypercapnia) may promote atrial remodelling by hypoxemia-induced systemic inflammation and pulmonary hypertension. As a consequence, right ventricular hypertrophy and diastolic dysfunction may induce further cardiac remodelling.5Hiram R. Naud P. Xiong F. et al.Right atrial mechanisms of atrial fibrillation in a rat model of right heart disease.J Am Coll Cardiol. 2019; 74: 1332-1347Crossref PubMed Scopus (42) Google Scholar Also, dynamic hyperinflation with subsequent thoracic pressure swings is hypothesised to increase sympathetic nerve activity. This complex interplay of mechanisms of cardiac remodelling and transient sympathetic nerve activity creates a complex and dynamic arrhythmogenic substrate for AF in patients with COPD.3Simons S.O. Elliott A. Sastry M. et al.Chronic obstructive pulmonary disease and atrial fibrillation: an interdisciplinary perspective.Eur Heart J. 2021; 42: 532-540Crossref PubMed Scopus (29) Google Scholar In this issue of the Canadian Journal of Cardiology, Noubiap et al. report on the relationship between respiratory function and incidence of AF in a prospective cohort from the UK Biobank.6Noubiap J.J. Tu S.J. Emami M. et al.Incident atrial fibrillation in relation to ventilatory parameters: a prospective cohort study.Can J Cardiol. 2023; 39: 614-622Abstract Full Text Full Text PDF Scopus (1) Google Scholar After exclusion of patients with previously diagnosed AF, a total of 348,219 participants were included in this study. AF occurred in 18,188 patients (5.2%) after a median follow-up time of 11.5 years. The authors showed an almost linear increasing risk of AF with every decline in forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and FEV1/FVC ratio after standardisation for sex, age, and height. When considering the presence of COPD or asthma at baseline, identified by self-report or hospital inpatient diagnosis, patients with COPD and asthma had 40% and 17% higher AF risks, respectively, compared with participants with neither of these conditions at baseline. This study adds to the available evidence from previous cohorts and confirms that respiratory function is associated with incident AF. Of note, this association is not unique to AF; decreased respiratory function also predicts other cardiovascular diseases. In the Atherosclerosis Risk in Communities Study, serial spirometry measurements showed that a rapid decline in lung function went hand in hand with an increased risk of subsequent cardiovascular complications.7Silvestre O.M. Nadruz Jr., W. Querejeta Roca G. Declining lung function and cardiovascular risk: the ARIC study.J Am Coll Cardiol. 2018; 72: 1109-1122Crossref PubMed Scopus (49) Google Scholar This increased risk of cardiovascular disease in patients with COPD has already been acknowledged by pulmonologists, and current COPD guidelines propose screening for concomitant cardiovascular disease in every COPD patient. In the case of AF, regardless of COPD diagnosis, the European Heart Rhythm Association recommends in their recent practice guide on the use of digital devices screening for AF systematically in all patients ≥ 65 years old and opportunistically those < 65 years old.8Svennberg E. Tjong F. Goette A. et al.How to use digital devices to detect and manage arrhythmias: an EHRA practical guide.Europace. 2022; 24: 979-1005Crossref PubMed Scopus (48) Google Scholar,9Schnabel R.B. Marinelli E.A. Arbelo E. et al.Early diagnosis and better rhythm management to improve outcomes in patients with atrial fibrillation: the 8th AFNET/EHRA consensus conference.Europace. 2022; 25: 6-27Crossref Scopus (11) Google Scholar The need for AF screening in COPD patients is further supported by the findings of a recent study that showed that 5-year mortality in patients with COPD who subsequently developed AF was high: 52.8% in those manifesting the arrhythmia.4Warming P.E. Garcia R. Hansen C.J. et al.The association of temporal sequence in atrial fibrillation and chronic obstructive pulmonary disease diagnosis and mortality risk.Eur Heart J Qual Care Clin Outcomes. 2023; 9: 128-134Crossref PubMed Google Scholar In addition to formal lung function testing, the study by Noubiap et al. showed that patients with self-reported asthma were also at an increased risk for AF.6Noubiap J.J. Tu S.J. Emami M. et al.Incident atrial fibrillation in relation to ventilatory parameters: a prospective cohort study.Can J Cardiol. 2023; 39: 614-622Abstract Full Text Full Text PDF Scopus (1) Google Scholar Data on the relationship between asthma and AF and on the involved mechanisms are scarce, and this area requires further research. The data presented by Noubiap et al. confirm the association between impaired respiratory function and AF. However, it remains unclear whether impaired respiratory function, COPD, and asthma represent a risk factor causally contributing to AF that may deserve structured assessment and management in patients to mitigate or prevent AF. Management of patients with AF and concomitant impaired respiratory function will require an interdisciplinary and integrated care approach. The fragmentation in care owing to superspecialisation between and within pulmonology and cardiology exposes patients and physicians to several challenges. Patients with AF and COPD present to either a specialised COPD or a specialised AF outpatient clinic, which likely puts comparable patients on completely different treatment pathways. For the effective implementation of AF screening in COPD or asthma patients, and for the implementation of screening for impaired respiratory function in AF patients, several hurdles need to be overcome. A recent Europe-wide survey aimed to evaluate current management of multimorbid AF patients, revealing that integrated care models were lacking for more than one-half of the respondents, and over one-third reported organisational or institutional issues and issues with patient adherence.10Lee G. Baker E. Collins R. et al.The challenge of managing multimorbid atrial fibrillation: a pan-European European Heart Rhythm Association (EHRA) member survey of current management practices and clinical priorities.Europace. 2022; 24: 2004-2014Crossref PubMed Scopus (1) Google Scholar Integrated care models in COPD outpatient clinics could be facilitated by the use of digital devices for AF screening, as have already been used widely in several clinical scenarios, and could be linked to a digital platform, as described for TeleCheck-AF, to ensure the transition from AF detection to early AF management.11Linz D. Pluymaekers N.A.H.A. Hendriks J.M. TeleCheck-AF for COVID-19.Eur Heart J. 2020; 41: 1954-1955Crossref PubMed Scopus (47) Google Scholar, 12Pluymaekers N.A.H.A. Hermans A.N.L. van der Velden R.M.J. et al.Implementation of an on-demand app-based heart rate and rhythm monitoring infrastructure for the management of atrial fibrillation through teleconsultation: TeleCheck-AF.Europace. 2021; 23: 345-352Crossref PubMed Scopus (41) Google Scholar, 13Linz D. Hermans A. Tieleman R.G. Early atrial fibrillation detection and the transition to comprehensive management.Europace. 2021; 23: ii46-ii51Crossref PubMed Scopus (12) Google Scholar Thus, for the screening and management of common pulmonologic comorbidities, such as COPD, sleep apnea, and asthma, in AF clinics, digital and remote care pathways may be an option. For example, Virtual-Safari is a novel virtual AF management pathway allowing remote sleep apnea testing in AF outpatient clinics with a short time to diagnosis and high patient satisfaction.14Verhaert D.V.M. Betz K. Gawałko M. et al.A virtual sleep apnoea management pathway for the work-up of atrial fibrillation patients in a digital remote infrastructure: Virtual-Safari.Europace. 2022; 24: 565-575Crossref PubMed Scopus (9) Google Scholar This example may provide a good framework for future digital interdisciplinary COPD management platforms to allow the structured work-up of respiratory function in patients treated for AF in AF outpatient clinics. In addition, for the implementation of screening, patient education is of utmost importance to improve adherence as well as patient involvement, acceptance, and self-management. Finally, in addition to novel integrated care solutions, intervention studies are required to test whether routine testing for respiratory function and treatment of COPD and asthma improves rhythm control and symptoms in patients with AF.