Steven Lubitz, M.D., MPH, cardiac electrophysiologist, Massachusetts General Hospital, presented the late-breaking VITAL-AF Trial at the 2020 American Heart Association (AHA) virtual meeting this week. The study looked at screening for atrial fibrillation (AF) in older adults at primary care visits using the AliveCor single-lead electrocardiogram (ECG) device that interfaces with a smartphone or iPad.
The study found screening for AF using a single-lead ECG at primary care visits was not associated with a significant increase in new AF diagnoses among individuals aged 65 years or older compared to usual care. However, screening may be associated with an increased likelihood of diagnosing AF among individuals aged 85 years or older.
Undiagnosed AFib is associated with increased risk of stroke. There is uncertainty about how best to screen for AF and guidelines differ regarding screening using ECGs. Methods: We conducted a cluster-randomized trial to evaluate whether screening using single-lead ECGs at primary care visits is effective for diagnosing AF.
Sixteen clinics were randomized 1:1 to an AF screening intervention which offered an AliveCor single-lead ECG to patients aged 65 years or older during routine vital sign assessments, or usual care. AliveCor readings were over-read by cardiologists. Confirmatory diagnostic testing and treatment decisions were made by the primary care provider.
New AF diagnoses were ascertained based on electronic case identification and manually adjudicated by a clinical endpoint committee. Results: 35,308 patients were included in the trial (n=17,643 intervention [91% screened], n=17,655 control). Patient characteristics were well-balanced between the intervention and control groups, including 12.7% versus 13.2% with prevalent AF, respectively. At one year, 1.52% of individuals in the screening group had new AF diagnosed versus 1.39% in the control group (relative risk [RR] 1.10; 95% confidence interval [CI] 0.92-1.30; P=0.30). New AF diagnoses in the screening and control groups varied by age (0.95% versus 1.00% for age 65-74; P=0.74; 1.84% versus 1.70% for age 75-84; P=0.58; 4.05% versus 2.68% for age 85+; P=0.02) (see figure). New anticoagulation was prescribed in 2.98% versus 2.90% of individuals in the screening and control groups, respectively, overall (RR 1.03; 95%CI 0.91-1.18; P=0.61), and in 72.8% versus 71% with new AF diagnoses (RR 1.02; 95%CI 0.92-1.14; P=0.70).