Subtypes of atrial fibrillation with concomitant valvular heart disease derived from electronic health records: phenotypes, population prevalence, trends and prognosis.
AIMS
To evaluate population-based electronic health record (EHR) definitions of atrial fibrillation (AF) and valvular heart disease (VHD) subtypes, time trends in prevalence and prognosis.


METHODS AND RESULTS
A total of 76 019 individuals with AF were identified in England in 1998-2010 in the CALIBER resource, linking primary and secondary care EHR. An algorithm was created, implemented, and refined to identify 18 VHD subtypes using 406 diagnosis, procedure, and prescription codes. Cox models were used to investigate associations with a composite endpoint of incident stroke (ischaemic, haemorrhagic, and unspecified), systemic embolism (SSE), and all-cause mortality. Among individuals with AF, the prevalence of AF with concomitant VHD increased from 11.4% (527/4613) in 1998 to 17.6% (7014/39 868) in 2010 and also in individuals aged over 65 years. Those with mechanical valves, mitral stenosis (MS), or aortic stenosis had highest risk of clinical events compared to AF patients with no VHD, in relative [hazard ratio (95% confidence interval): 1.13 (1.02-1.24), 1.20 (1.05-1.36), and 1.27 (1.19-1.37), respectively] and absolute (excess risk: 2.04, 4.20, and 6.37 per 100 person-years, respectively) terms. Of the 95.2% of individuals with indication for warfarin (men and women with CHA2DS2-VASc ≥1 and ≥2, respectively), only 21.8% had a prescription 90 days prior to the study.


CONCLUSION
Prevalence of VHD among individuals with AF increased from 1998 to 2010. Atrial fibrillation associated with aortic stenosis, MS, or mechanical valves (compared to AF without VHD) was associated with an excess absolute risk of stroke, SSE, and mortality, but anticoagulation was underused in the pre-direct oral anticoagulant (DOAC) era, highlighting need for urgent clarity regarding DOACs in AF and concomitant VHD.
['Banerjee|Amitava|A|', 'Allan|Victoria|V|', 'Denaxas|Spiros|S|', 'Shah|Anoop|A|', 'Kotecha|Dipak|D|', 'Lambiase|Pier D|PD|', 'Joseph|Jacob|J|', 'Lund|Lars H|LH|', 'Hemingway|Harry|H|']
D000368:Aged D000369:Aged, 80 and over D000925:Anticoagulants D001281:Atrial Fibrillation D001705:Bioprosthesis D058385:Cardiac Valve Annuloplasty D002423:Cause of Death D004617:Embolism D004739:England D065427:Factor Xa Inhibitors D005260:Female D006349:Heart Valve Diseases D006350:Heart Valve Prosthesis D019918:Heart Valve Prosthesis Implantation D000083302:Hemorrhagic Stroke D006801:Humans D000083242:Ischemic Stroke D008297:Male D008875:Middle Aged D009026:Mortality D010641:Phenotype D015995:Prevalence D011379:Prognosis D016016:Proportional Hazards Models D020521:Stroke D014859:Warfarin
Atrial fibrillation Valvular heart disease Electronic health records Stroke Systemic embolism Mortality