OBJECTIVES: To explore the recovery time of atrioventricular conduction and its influencing factors in patients presenting late and diagnosed with inferior wall acute myocardial infarction (AMI) and high-degree atrioventricular block (AVB) on admission. METHODS: We conducted a retrospective study in patients presenting >
12 h after symptom onset and diagnosed with inferior wall AMI and new onset second-degree type 2 or third-degree AVB on admission. All of them underwent percutaneous coronary intervention (PCI). The clinical characteristics, time to PCI and time to AVB recovery after symptom onset were studied. RESULTS: Among the 80 patients, 68 were male, aged 63 ± 10 years. The median admission time after symptom onset was 36 h. 10 patients presented with second-degree type 2 AVB and 70 patients with third-degree AVB. The median time of AVB recovery from AMI onset was 5d (Q1-Q3:4-7d
Min-max: 1-15d). Patients were divided into two groups according to the median AVB recovery time. Compared to the late recovery group (>
5 days), patients in the early recovery group (≤ 5 days) had shorter admission time after AMI onset (P <
0.002) and received PCI earlier (P <
0.002). Multivariate Logistic regression analysis showed that admission time from AMI onset (OR:1.032, 95%CI: 1.013-1.052, P = 0.002) and time from AMI onset to PCI (OR: 1.449, 95%CI: 1.163-1.804, P = 0.002) were independent factors for early AVB recovery. CONCLUSIONS: In patients presenting late with inferior wall AMI complicated with high-degree AVB, the median time of AVB recovery was 5 days. Shorter admission time from AMI onset and earlier PCI treatment were independently associated with earlier AVB recovery.