Abstract W MP68: MRI Infarct Patterns Do Not Predict Long-Term Cardiac Rhythm Recorder Findings
Intro: It has been hypothesized that stroke/TIA patients with occult paroxysmal atrial fibrillation (PAF) have characteristic embolic patterns of cerebral infarction. We tested this hypothesis in patients studied with extended cardiac monitoring and MRI.
Methods: Acute ischemic stroke patients with a negative 24-hour Holter monitor were prospectively enrolled in a study of event-triggered external loop recordings for 21 days. Fifty-five of 88 patients had acute MRI scans. Lesion volumes were calculated planimetrically on diffusion-weighted MRI (DWI) and fluid-attenuated inversion recovery (FLAIR) sequences. Leukoaraiosis volumes (FLAIR), acute and chronic lesion number and distribution were also assessed.
Results: PAF was detected in 34.5% (19/55) of patients. Duration of PAF was <30s in 52.6% (10/19) of patients. Median(IQR) DWI lesion volumes (ml) were similar between patients with (1.74 (4.57)) and without PAF (1.57 (13.39), p=0.70). Median(IQR) chronic ischemic lesion volume on FLAIR (ml) in patients with (0.34 (3.28)) and without PAF (0.28(3.01)) was similar (P=0.82). Leukoaraiosis volumes were also similar (8.46 (12.51) vs. 3.42 (5.25), P=0.06), as were the total number of lesions (4 (6) vs. 5 (5), P=0.48), and total number of arterial territories affected (2 (2) vs. (2 (2), P=0.09). Patients with PAF duration <30s and >30s had similar median DWI volumes (2.21 (4.08) vs. 0.13 (6.24), P=0.61), FLAIR volumes (0.34 (2.87) vs. 0.88 (12.24), P=0.89), leukoaraiosis volumes (7.69 (13.11) vs. 8.46 (26.79), P=1.00), total number of lesions (6.5 (6) vs. 3 (7), P=0.72), and total number of arterial territories affected (3 (2) vs. 2 (3), P=0.84).
Conclusion: Ischemic lesion volume, number and distribution in patients with occult PAF are similar to those with other mechanisms of infarction. In addition, patients with even very brief runs of PAF (<30s) have similar ischemic lesion loads to those with longer duration episodes. Our data suggest all ischemic stroke patients should be investigated for PAF.
Author Disclosures: K. Phoa: None. M. Kate: None. A. Shuaib: None. I. Yaseen: None. K. Butcher: None. B. Buck: None.
- © 2014 by American Heart Association, Inc.