Refining Residual Ischemic Stroke Risk in Anticoagulated Atrial Fibrillation Using Index Outpatient LA Diameter: The...

Area of Science:

• Cardiology
• Stroke Prevention
• Medical Imaging

Background:

• Atrial fibrillation (AF) significantly elevates ischemic stroke risk.
• Current risk stratification scores like CHA2DS2-VA have limitations, especially for intermediate-risk patients.
• Left atrial (LA) enlargement, a marker of cardiac remodeling, may enhance stroke risk prediction in AF.

Purpose of the Study:

• To assess if incorporating LA diameter into the CHA2DS2-VA score (CHA2DS2-VALa) improves ischemic stroke prediction in AF patients.
• To develop and evaluate a multivariable model and compare its performance against existing scores.
• To determine the predictive value of LA enlargement for stroke events.

Main Methods:

• Retrospective analysis of 1648 AF patients.
• Standardized echocardiography for LA diameter measurement, with enlargement defined by ROC-derived cut-off (>4.7 cm).
• Long-term follow-up for imaging-confirmed ischemic stroke events, validated through comprehensive medical records.

Main Results:

• Patients with LA enlargement (>4.7 cm) experienced higher stroke event rates (3.8% vs. 2.1%, p<0.001).
• LA enlargement independently predicted stroke events (OR 1.97, p<0.001) with strong discriminatory ability (AUC 0.872).
• The CHA2DS2-VALa score demonstrated superior stroke prediction compared to CHA2DS2-VA (log-rank p<0.001).

Conclusions:

• The CHA2DS2-VALa score enhances stroke risk stratification in AF by integrating LA diameter.
• This echocardiography-based modification provides a simple and practical method for refining risk assessment.
• Further prospective validation in diverse populations is recommended to confirm these findings.