Evaluation of natriuretic peptide levels and echocardiography findings in patients with micro AF

Micro-AF, defined as brief episodes of rapid irregular atrial activity, is a predictor for atrial fibrillation (AF), which is an important cause of mortality and morbidity. However, micro-AF may be overlooked diagnosis. The aim of our study is to investigate the predictability of laboratory, electrocardiographic and echocardiographic findings for the diagnosis of micro-AF. Micro-AF was defined as sudden onset of irregular tachycardia with episodes of ≥5 consecutive supraventricular beats and total absence of p-waves, lasting less than 30 s. Two groups were formed as patients with and without Micro-AF detected in 24-hour rhythm Holter analysis. Laboratory parameters, electrocardiographic and echocardiographic findings of the two groups were compared. A total of 90 patients, 45 patients with micro AF and 45 patients in the control group, were included in our study. Serum Troponin T (13,09±11,45 ng/dl and 4,41±2,46 ng/dl; p<0.001) and pro-BNP (375,57±636,68 pg/ml and 63,19±56,82 pg/ml; p<0.001) Micro It was found to be higher in the AF group. Serum ANP values (160,19±83,94 ng/L and 278.63±196.51 ng/L; p<0.001) were higher in the control group.We found a 63.4 pg/dl Pro-BNP cut-off value for the diagnosis of micro-AF with a sensitivity of 91.1% and a specificity of 73.3%. Each 1 pg/dl increase in serum Pro-BNP level increased the risk of Micro-AF by 1.8%. In ECG evaluation, P-max (113,00±10,25 and 98,00±10,47 ms; p<0,001), P-min (73,89±5,53 and 70,00±6,39 ms; p<0,001 ) and P-dd (39,11±7,93 and 28,00±7,64 ms; p<0,001) were longer in the Micro-AF group. In echocardiographic findings, interventricular septum wall thicness (11,14±1,37 and 9,65±2,65 mm; p=0,003), posterior wall thicness (12,13±6,58 and 9,78±2,63 mm;p=0,002) and left atrial diameter ( 35,92±1,30 and 34,62±1,77mm; p<0,001) were found to be higher in the Micro-AF group. In the micro-AF group, mitral A wave velocity was higher (0,79±0,18 and 0,71±0,13 cm/h; p=0,019). e' and s' wave velocities measured were lower, and E/e' ratios were higher from 6 regions. Atrial electro-mechanical delay times (PA) were significantly higher in the Micro AF group. Lateral tricuspid PA cut-off value of 18,5 seconds was determined for micro-AF with a sensitivity of 93,3% and a specificity of 91,1%; Lateral Septal PA cut-off value of 11,5 seconds was determined with 95,6% sensitivity and 75,6% specificity. In conclusion, in our patients who applied to the outpatient clinic with the complaint of palpitation, serum pro-BNP, serum troponin T levels, P-max, P-dd times in ECG evaluation, left atrial diameter in echocardiographic evaluation, E wave velocity, A wave velocity, e' measurement, E/e ' rate and measurement of AEMD durations may allow us to identify AF patients early.