ABSTRACT
BACKGROUND: In approximately 10% of patients with implanted pacemakers or defibrillators, previously unrecognized atrial fibrillation (AF) is detected within 3â¯months. It is unknown whether elderly patients without implanted devices have a similar prevalence of undiagnosed AF using non-invasive ECG monitoring, and if this approach to screening in this population is cost-effective. METHODS: Individuals ≥80â¯years old attending outpatient clinics without a history of AF and with hypertension and one additional risk factor underwent 30â¯days of continuous ECG monitoring with an option for an additional 30â¯days of monitoring if no AF was detected. The primary outcome was AFâ¯≥â¯6â¯min. Cost-effectiveness to prevent stroke was estimated using a Markov model based on observed AF detection rates and data from the published literature. RESULTS: Among 129 patients enrolled, 100 initiated monitoring for an average duration of 36⯱â¯21â¯days. The proportion of patients that completed at least 30â¯days of monitoring was 59%. Average age was 84⯱â¯3â¯years and mean CHA2DS2-VASc score was 4.5⯱â¯1.2. AFâ¯≥â¯6â¯min was documented in 14%, ≥6â¯h in 8%, and ≥24â¯h in 3%. One week of monitoring costed $50,000 per quality-adjusted life-year-gained, 30â¯days and 60â¯days of monitoring costed $70,000 and $84,000, respectively. CONCLUSIONS: Continuous non-invasive ECG monitoring is feasible in elderly patients. Undiagnosed AF is present in many elderly individuals, with 1 in 7 having episodes lasting ≥6â¯min. One week of monitoring may be cost-effective for stroke prevention in this population.
Subject(s)
Atrial Fibrillation , Stroke , Aged , Aged, 80 and over , Atrial Fibrillation/diagnosis , Atrial Fibrillation/epidemiology , Cost-Benefit Analysis , Electrocardiography , Electrocardiography, Ambulatory , Humans , PrevalenceABSTRACT
BACKGROUND: Atrial fibrillation (AF) is often detected for the first time in patients hospitalized for medical illness or non-cardiovascular surgery. AF occurring transiently with stress (AFOTS) describes this manifestation of AF, which may either be the result of a non-cardiac stressor, or existing paroxysmal AF that was not previously detected. Current estimates of AFOTS incidence are imprecise: ranging from 1 to 44%, owing to the marked heterogeneity in patient populations, identification and methods used to detect AFOTS. METHODS: The prospective, two-centre epidemiological AFOTS Incidence study will enroll 250 consecutive participants without a history of AF but with at increased risk of AF (Ageâ¯≥â¯65 or >50 with one risk factor for AF) admitted to intensive care units (ICUs) for medical illness or non-cardiac surgery. Upon admission, participants will wear an ECG patch monitor that will remain in place for 14â¯days, or until discharge from hospital. Patients' consent to participation is deferred for up to 72â¯h after admission. The primary endpoint is the incidence of AF lasting ≥30â¯s. The study is powered to detect an AF incidence of 17%⯱â¯5%. RESULTS: We conducted a vanguard feasibility study, and 55 participants have completed participation. The median duration of monitoring was seven days. AF was detected by the clinical team in 8 participants (14%; 95% Confidence Interval 7-26%). CONCLUSIONS: The AFOTS Incidence study will employ a systematic and highly sensitive protocol for detecting AFOTS in medical illness and non-cardiac surgery ICU patients. This study is feasible and will provide a reliable estimate of the true incidence of AFOTS in this population.