Left ventricular thrombus in takotsubo syndrome and ST-elevation myocardial infarction

Background/Introduction Both takotsubo syndrome (TS) and ST-elevation myocardial infarction (STEMI) are conditions characterized by left ventricular dysfunction. While left ventricular (LV) thrombus is a known complication of LV dysfunction, its epidemiology in these two patient groups is not fully understood. Purpose To compare the incidence, timing, predictors, and resolution of LV thrombus in patients with TS and STEMI. Methods We used data from the STAMI (Stunning Takotsubo versus Acute Myocardial Infarction, NCT04448639) study, which prospectively enrolled patients with TS and STEMI at Sahlgrenska University Hospital, Gothenburg, Sweden. Serial echocardiography was performed on admission, and at days 1, 2, 3, 7, 14, and 30. Predictors of LV thrombus were identified using Cox regression analyses. Results From December 2019 to October 2024, 314 patients were included, 68 with TS and 246 with STEMI, of whom 148 had anterior STEMI. The predicted mean left ventricular ejection fraction (LVEF) on admission was lower in TS (39%) compared to anterior STEMI (46.7%) and non-anterior STEMI (52.8%). However, recovery was faster and more pronounced in TS, with a mean LVEF of 60.4% at day 30, compared to 53.8% in anterior STEMI and 55.3% in non-anterior STEMI (Table 1). LV thrombus was not observed in any of the TS patients but occurred in 20 out of 246 (8.1%) STEMI patients. All but one LV thrombus was found in anterior STEMI. All LV thrombi in anterior STEMI were detected within 7 days, while the single non-anterior LV thrombus was found on day 30. All patents with LV thrombi were treated with anticoagulation, initially low-molecular-weight heparin followed by oral anticoagulation (DOAC or warfarin). The resolution rate by day 30 was 16 out of 20 (80%). Predictors of LV thrombus included lower LVEF and higher troponin levels (Figure 1). Conclusions Despite the lower LVEF in TS compared to STEMI, LV thrombus was exclusively observed in STEMI. Nearly all LV thrombi were found in anterior STEMI within the first week, with a high resolution rate at 30 days. Our findings highlight the pathophysiological differences between these two conditions, warranting further investigations and having implications for their differing surveillance needs after TS and STEMI.