Experience in the management of infants with multifocal atrial tachycardia

Purpose. To study the clinical course of multifocal atrial tachycardia (MAT) and to evaluate the effectiveness of antiarrhythmic therapy (AAT) in patients with onset of arrhythmia before the age of 1 year.Methods. The study included 15 children with primary registration of MAT at the age of 2.04±2.27 months, 4 of them - in utero. The follow-up period was 35.9±26.9 months (Me 29 months). All patients underwent laboratory monitoring, 12-lead ECG recording, 24-hour ECG monitoring, echocardiography at baseline and during time of observation.Results. Tachycardia was persistent in 80% of patients. Tachycardia-induced cardiomyopathy (TIC) was present in 7 (46%) patients. Structural heart disease was detected in 6 patients. The average heart rate at the onset of the disease was 157.9±23.78 bpm, the maximum - 256.7±35.84 bpm. Fourteen (93.3%) children received AAT. Seven patients were prescribed propranolol first, 6 - amiodarone, 1 - digoxin. Monotherapy was effective in 2 patients. Combined AAT was used in 12 patients, including three children with three drugs combination. No benefits were found for any of the drugs combinations. Stable sinus rhythm at the time of discharge was observed in 4 (28,6%) patients, sinus rhythm with atrial ectopic activity was registered in 2 of them; criteria for normosystole were achieved in 7 patients; in one child with TIC daytime tachysystole persisted despite three-component AAT, but echocardiography parameters improved. Arrhythmia was disappeared in 13 (86.6%) patients; the duration of arrhythmia in them from 1 to 15 months, duration of AAT - 1 ±7.5 months (Me 9.5 months). MAT persists in two patients with structural heart disease. One patient underwent radiofrequency ablation at the age of 5, with no effect. One patient had side effects from therapy that required correction. There were no lethal outcomes.Conclusion. MAT with a debut at the age of 1 year with timely prescribed treatment has a favorable course and a good prognosis, but the probability of AAT resistance is high. These cases require a long-term selection of therapy using various combinations of antiarrhythmic drugs. Heart rate control strategy can be sufficient to prevent the development of TIC.

New Discovery of Left Atrial Macroreentry Tachycardia: Originating from the Spontaneous Scarring of Left Atrial Anterior Wall

Aims. This study sought to describe left atrial macroreentry tachycardia (LAMRT) originating from the spontaneous scarring of left atrial anterior wall (LAAW) and its clinical and electrophysiological characteristics, mechanisms, and the formation of substrates. Methods and Results. 9 of 123 patients (89% female, age 79.78 ± 5.59 years) had LAMRT originating from the LAAW with no cardiac surgery or prior left atrial (LA) ablation. The mean tachycardia cycle length (TCL) was 241.67 ± 38.00 milliseconds. Spontaneous scars areas and low voltage areas (LVAs) in the LAAW were found in all patients. Successful ablation of the critical isthmus caused termination of the LAMRT and was not inducible in all patients. Arrhythmogenic substrates of LAMRT were the spontaneous scars of LAAW, which matched with the aorta or/and pulmonary artery contact area. The area under the curve (AUC) of age and combination of gender and age for predicting the LAMRT originating from the LAAW were 0.918 and 0.951, respectively, with a cutoff value of ≥73.5 years of age and gender (female) predicting LAMRT with 88.9% sensitivity and 89% specificity. Conclusion. Combination of gender and age provides a simple and useful criterion to distinguish LAMRT from cavotricuspid isthmus- (CTI-) dependent atrial tachycardia in macroreentry atrial tachycardia (MRAT) in patients without a history of surgery or ablation. Aorta or/and pulmonary artery contacting LA may be related to spontaneous scars. Ablation the isthmus eliminated LAMRT in all patients.

Surveillance of arrhythmia in post-myocardial infarction patients using wearable ECG patch devices: a prospective cohort study (Preprint)

BACKGROUND Acute myocardial infarction may be associated with new-onset arrhythmias. Myocardial infarction patients may manifest with serious arrhythmias such as ventricular tachyarrhythmias or atrial fibrillation. Frequent, prolonged electrocardiogram (ECG) monitoring can prevent devastating outcomes by these arrhythmias. OBJECTIVE We investigated the incidence of arrhythmias in post-myocardial infarction patients using a patch-type device: ATP-C120. METHODS This study is a non-randomized, single-center, prospective cohort study. We evaluated 71 patients with post-myocardial infarction who had been admitted to our hospital. The ATP-C120 device was attached for 11 days and analyzed by two cardiologists for new-onset arrhythmic events. RESULTS One participant was concordantly diagnosed with atrial fibrillation. Atrial premature beats occurred in 91.5% and 84.5% of participants, and ventricular premature beats occurred in 53.5% and 62.0%, respectively. Interestingly, 56.3% of the patients showed less than 2 minutes of sustained paroxysmal atrial tachycardia. Among participants with atrial tachycardia, the use of beta blockers was significantly lower (70.0% vs. 90.3%, p=0.037). However, different dosages of beta blockers did not show significant differences. CONCLUSIONS Wearable patch ECG monitoring devices are easy to apply and can correlate symptoms and ECG rhythm disturbances among post-myocardial infarction patients. Further study is necessary regarding clinical implications and appropriate therapies for arrhythmias detected early, post-myocardial infarction, to prevent adverse outcomes.