Background: Detecting concealed paroxysmal atrial fibrillation (pAF) is a major focus in the workup of ischemic-stroke-patients. The minimal ECG-monitoring for stroke patients was recently expanded from 24 to 72 hours. However, it has been shown that even more prolonged monitoring reveals further pAF-cases. Our aim was to determine, whether known predictors for underlying pAF differ between stroke patients with AF that occurs on shorter (72h) or more prolonged ECG-monitoring (>72h).
Methods: The Find-AFRANDOMISED-trial (NCT01855035) evaluated 3x10-day Holter-ECG vs. standard-care in patients > 60 years with acute ischemic strokes with the primary endpoint of novel pAF after 6 months. In this subanalysis we included only patients in the intervention arm. We compared relevant clinical characteristics (age, gender, body-mass-index = BMI and stroke severity, expressed by the Natrional Institute of Health Stroke Scale, NIHSS-Score), echocardiographic signs of left atrial (LA) dilation (LA diameter, left atrial volume index), blood levels of brain natriuretic peptide (BNP) and rates of supraventricular ectopic activity (longest supraventricular, SV-runs and atrial premature beats, APB) during the AF-free intervals of the first 10-day-Holter-ECG.
Results: 402 patients were initially included, 200 in the intervention were analyzed. Baseline characteristics including age (72 65;80 vs. 72 years, 65;76; p = 0.227), gender (55.6 % females vs. 40.5 %; p = 0.149) and NIHSS-Score (4, 2:9 vs. 3, 1;5; p = 0.069) were similar between patients with and without AF. Those with pAF showed significantly larger left atria (LAVI 38.95 ml/m2 36.13;55.56 vs. 33.3, 26.6;43.5; p = 0.019), longer SV-runs (20, 13;30 vs. 13, 9;20; p = 0.007), more frequent APB/h (19.73, 2.45;47.5 vs. 1.82, 0.53;14.1; p < 0.001) and increased BNP-levels (56 ng/l 30;194 vs. 25, 11;57; p < 0.001). However, we found no significant differences between those with AF detected during standard (72 hour-) and prolonged (>72 hour-) ECG-monitoring.
Conclusions: There are no relevant characteristic differences between patients with AF detected during standard 72-hour- and prolonged ECG-monitoring.