There are limited data on the prevalence and an outcome of left ventricular (LV) aneurysms following acute myocardial infarction (AMI). Using the National Inpatient Sample during 2000 to 2017, a retrospective cohort of AMI admissions was evaluated for LV aneurysms. Complications included ventricular arrhythmias, mechanical, cardiac arrest, pump failure, LV thrombus, and stroke. Outcomes of interest included in-hospital mortality, temporal trends, complications, hospitalization costs, and length of stay. A total 11,622,528 AMI admissions, with 17,626 (0.2%) having LV aneurysms were included. The LV aneurysm cohort was more often female, with higher comorbidity, and admitted to large urban hospitals (all p < 0.001). In 2017, compared with 2000, there was a slight increase in LV aneurysms prevalence in those with (adjusted odds ratio [aOR] 1.57 [95% confidence interval {CI} 1.41 to 1.76]) and without (aOR 1.13 [95% CI 1.00 to .127]) ST-segment-elevation AMI (p < 0.001 for trend). LV aneurysms were more commonly noted with anterior ST-segment-elevation AMI (31%) compared with inferior (12.3%) and other (7.9%). Ventricular arrhythmias (17.6% vs 8.0%), mechanical complications (2.6% vs 0.2%), cardiac arrest (7.1% vs 5.0%), pump failure (26.3% vs 16.1%), cardiogenic shock (10.0% vs 4.8%) were more common in the LV aneurysm cohort (all p < 0.001). Those with LV aneurysms had comparable in-hospital mortality compared with those without (7.4% vs 6.2%; aOR 1.02 [95% CI 0.90 to 1.14]; p = 0.43). The LV aneurysm cohort had longer length of hospital stay, higher hospitalization costs, and fewer discharges to home. In conclusion, LV aneurysms were associated with higher morbidity, more frequent complications, and greater in-hospital resource utilization, without any differences in in-hospital mortality in AMI.