Was the atrioventricular block similar in anterior and inferior ST-elevation myocardial infarction?

Abstract

Abstract Funding Acknowledgements Type of funding sources: None. OnBehalf Portuguese Registry of Acute Coronary Syndromes Background The presence of atrioventricular block (AVB) in ST-elevation myocardial infarction (STEMI) is more frequently registered when is identified in the inferior leads. However, AVB maybe occurs in anterior STEMI, yet the AVB and STEMI localization maybe had different implications. Objective Evaluate the impact and prognosis of AVB according to the STEMI localization. Methods Multicenter retrospective study, based on the Portuguese Registry of Acute Coronary Syndrome between 1/10/2010-3/05/2020. Patients were divided into two groups: A – patients with anterior STEMI, and B – patients with inferior STEMI. Were excluded patients without a previous cardiovascular history or clinical data regarding AVB occurrence. Logistic regression was performed to assess AVB as a prognostic marker in STEMI patients. Results From 32157 patients, was identified 462 with AVB, 72 in group A (15.6%) and 390 in group B (84.4%). Both groups were similar regarding gender (p = 0.710), age (p = 0.068), body mass index (p = 0.535), admitly directly to cat lab (p = 0.635), initial symptons until first medical contact (p = 0.561), smoker status (p = 0.483), diabetes mellitus (p = 0.331), coronary artery disease (p = 0.053), previous stroke (p = 0.332), peripheral artery disease (p = 0.348), chronic kidney disease (p = 0.425), systolic blood pressure (p = 0.057), multivessel diasease (p = 0.235), new-onset of atrial fibrillation (p = 0.582), cardiac arrest (p = 0.062) and stroke complication (p = 0.685). Group B had higher left ventricular ejection fraction (LVEF) >50% (16.9 vs 60.7%, p < 0.001). On the other hand, group A had more arterial hypertension (79.7 vs 66.2%, p = 0.027), dislipidaemia (58.2 vs 54.4%, p = 0.038), heart rate at admission (81 ± 20 vs 59 ± 23, p < 0.001), Killip-Kimball class > I (45.7 vs 29.6%, p = 0.008), sinus rhythm at admission (84.5 vs 72.6%, p = 0.035), heart failure complication (65.3 vs 37.1%, p < 0.001), cardiogenic shock complication (42.3 vs 24.7%, p < 0.001), ACS mechanical complication (8.3 vs 3.1%, p = 0.047), sustained ventricular tachycardia during ACS hospitalization (19.4 vs 8.5%, p = 0.005) and hospitalization death (52.9 vs 44.7%, p < 0.001). Logistic regression revealed that AVB in inferior STEMI was a predictor of new-onset of atrial fibrillation (odds ratio (OR) 3.817, p = 0.038, confidence interval (CI) 1.123-12.975), with a R2 Nagelkerke 24.4. Also, revealed that AVB in anterior STEMI was a predictor of death (OR 0.111, p < 0.001, CI 0.034-0.366), with a R2 Nagelkerke 55.2. Conclusions AVB in inferior STEMI was a predictor of new-onset of atrial fibrillation and AVB in anterior STEMI was a predictor of death.