CHF, Left Atrial Enlargement Predictive of AF in Patients With Ischemic Stroke

In patients with ischemic stroke that is attributable to large or small vessel disease, congestive heart failure (CHF) and left atrial enlargement (LAE) are associated with a significantly increased risk for detection of poststroke atrial fibrillation (AF). These are the findings of a study published in JAMA Neurology.

Recognizing that identification of predictors of AF could prove useful when considering use of an insertable cardiac monitor (ICM) in routine poststroke clinical care, researchers sought to establish the link between commonly evaluated risk factors and poststroke detection of new AF in the Stroke AF cohort monitored by an ICM. In the study, Rate of Atrial Fibrillation Through 12 Months in Patients With Recent Ischemic Stroke of Presumed Known Origin (STROKE AF; ClinicalTrials.gov Identifier: NCT02700945), researchers compared intervention, including the use of ICM monitoring vs site-specific usual care (ie, short-duration external cardiac monitoring).

This was a prespecified analysis of the randomized STROKE-AF trial, which researchers enrolled patients between April 1, 2016, and July 12, 2019, with a primary follow-up through 2020 that had a mean duration of 11.0±3.0 months. All eligible participants were chosen from 33 clinical research sites in the United States. All of the participants fulfilled the following criteria: (1) had experienced an index stroke that was attributed to large-vessel or small vessel disease; (2) aged >60 years; (3) aged 50-59 years of age with ≥1 additional stroke risk factor.

The subanalysis included a total of 242 participants who were randomly assigned to the ICM group in the STROKE-AF trial. The mean participant age was 66.6±9.3 years. Overall, 96 of the patients were men and 144 were women (2 patients had missing baseline data and left the study early). Among the 242 individuals who were monitored with ICM, 27 of them developed AF (mean age, 66.6±9.3 years).

Univariate predictors of AF detection included the following:

• age (per 1-year increments: hazard ratio [HR], 1.05; 95% CI, 1.01-1.09; P =.02);
• CHA₂DS₂-VASc (C=congestive heart failure; H=hypertension; A=age ≥75 years; D=diabetes mellitus; S=stroke, transient ischemic attack, or transient ischemic event; V=vascular disease; A=age 65 to 74 years; Sc=sex category) risk score (per point: HR, 1.54; 95% CI, 1.15-2.06; P =.004);
• chronic obstructive pulmonary disease (HR, 2.49; 95% CI, 0.86-7.20; P =.09);
• CHF (with preserved or reduced ejection fraction (HR, 6.64; 95% CI, 2.29-19.24; P <.001);
• LAE (HR, 3.63; 95% CI, 1.55-8.47; P =.003);
• QRS duration (HR, 1.02; 95% CI, 1.00-1.04; P =.04); and
• kidney dysfunction (HR, 3.58; 95% CI, 1.35-9.46; P =.01).

Per multivariable modeling in 197 individuals, only CHF and LAE remained statistically significant predictors of AF (HR, 5.06; 95% CI, 1.45-17.64; P =.05 and HR, 3.32;
95% CI, 1.34-8.19; P =.009, respectively).

Additionally, the rate of detection of AF at 12 months among participants with CHF and/or LAE (40 of 142 participants) was significantly higher compared with those with neither condition (23.4% vs 5.0%, respectively; HR, 5.1; 95% CI, 2.0-12.8; P <.001).

Several limitations of the present analysis warrant mention. Because the study was not powered to detect clinical predictors of AF, even though the data were obtained prospectively and in a randomized setting, other clinical characteristics may not have attained statistical significance. Further, the limited sample size involved may explain why such variables as age and CHA₂DS₂-VASc risk score did not reach statistical significance with use of the current modeling.

The researchers concluded, “Although preliminary in nature, if the findings from our study are replicated in other cohorts, then the associations of CHF and LAE with AF may be useful when considering an ICM in routine poststroke clinical care.”

Disclosure: Some of the study authors have declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.