Abnormal atrial activation at surface electrocardiogram examination in born underweight young adults

Introduction: Recent published data demonstrated how subjects born preterm are at higher risk of developing early atrial fibrillation (AF). Materials and Methods:The surface ECG of twenty-four adults, former preterm infants born with an extremely low birth weight (ex-ELBW; mean age at study: 23.2±3.3 years; mean gestational age: 27.8±2.3 weeks; mean birth weight: 840±120.1 grams), were compared with those of 24 healthy counterparts born at term (C). A few parameters known to be capable of predicting a predisposition to develop AF were examined: P wave duration and dispersion, P terminal force, isoelectric interval length, PR interval length, and advanced interatrial blocks. Results: A shorter PR interval length was found in ex-ELBW compared to C (p<0.0003) as well as longer P wave duration and dispersion, p terminal force, and isoelectric interval (p<0.0001, p<0.0001, p<0.01, and p<0.0004, respectively). Four cases of advanced interatrial block were detected in ex-ELBW, and none in C (p<0.0001). P wave duration, PR interval length, and P wave dispersion were significantly correlated with birth weight (r=0.51 p<0.01, r=0.46 p<0.02, and r=0.42 p<0.04, respectively). When excluding the possible influence of gestational age on birth weight, P wave duration and dispersion were found to be the only statistically significant determinants of abnormal atrial electrical activation (p<0.03 and p<0.04, respectively). On the contrary, when excluding the possible influence of birth weight on gestational age, only P wave duration remained statistically significant (p<0.05). Conclusions: Surface ECG findings of abnormal atrial activity in ex-ELBW may explain their previously reported predisposition to developing AF.