Left ventricular thrombus worsens outcome after acute STEMI

Cases of in-hospital left ventricular (LV) thrombus are rare following acute ST-elevation myocardial infarction (STEMI), a recent study has found. Nevertheless, LV thrombus is associated with worse clinical outcomes.

Accessing the Nationwide Inpatient Sample database, researchers identified 1,035,888 STEMI patients. Outcomes of interest were in-hospital complications, length of hospital stay, total hospital charges and the factors correlated with LV thrombus incidence. Overall, only 0.2 percent (n=1,982; mean age, 61.9±0.7 years; 24.7 percent female) developed LV thrombus.

Patients with LV thrombus were more likely to develop in-hospital ischaemic stroke (adjusted odds ratio [OR], 5.58, 95 percent confidence interval [CI], 3.53–8.82). The same was true for the risk of in-hospital mortality, though only to a marginal extent (adjusted OR, 1.006, 95 percent CI, 0.54–1.87).

Moreover, those with LV thrombus had a significantly longer hospital stay (8.12±0.36 vs 4.52±0.03 days; p<0.001) and sustained greater costs ($119,463±6,516 vs $85,352±1,139; p<0.001) than their counterparts who did not develop the condition.

Among the factors that increased the likelihood of developing LV thrombus were reduced ejection fraction, either because of chronic (adjusted OR, 2.24, 95 percent CI, 1.73–2.90) or acute (adjusted OR, 1.64, 1.15–2.34) heart failure, and the presence of LV aneurysm (adjusted OR, 5.32, 95 percent CI, 2.63–10.75). Thrombocytopoenia and coagulation defects, on the other hand, reduced the risk of LV thrombus (adjusted OR, 0.44, 95 percent CI, 0.23–0.87).

“[O]ur study may provide further help in identifying STEMI patients who are at higher risk of developing in-hospital LV thrombus, and therefore guide cost-effective utilization of diagnostic procedures,” said researchers.