P1296 Effects of contact-to-balloon time on variations of the left ventricle global and regional function during hospitalization of STEMI patients: an echocardiographic study

Abstract Background Ischemic time duration is one of the most important determinants of infarct size in patients with ST-segment elevation myocardial infarction (STEMI). An early reperfusion with percutaneous coronary intervention (PCI) therapy reduces the adverse events and mortality. It also influences the wall motion abnormalities and left ventricular ejection fraction (LVEF), which can be easily detected by a standard transthoracic echocardiogram (TTE). Purpose Aim of our study was to assess the immediate effects of an early percutaneous revascularization in STEMI patients on variations of the left ventricle (LV) global and regional function. Methods The study population consists of 141 consecutive patients with STEMI undergoing PCI from January to June 2018. The population was divided into two groups basing on first medical contact-to-balloon time (C2B), respectively ≤90 minutes and >90 minutes. Cardiac biomarkers were obtained uniformly. A standard TTE was performed in all patients, at moment of in-hospital admission and at the time of discharge, recording the LV wall motion abnormalities and LVEF, using the wall motion score index (WMSI) and modified Simpson’s rule, respectively. Finally, we performed a sub-analysis in the group of patients who showed an improvement of the LVEF ≥10% at discharge. Results In both groups at baseline, patients suffered from a moderately reduced LVEF (41 ± 8.3% in ≤90 min group vs 40.97 ± 8.91% in >90 min group, p = ns). A WMSI >1 was recorded uniformly: 1.78 ± 0.39 in patients with C2B ≤90 min and 1.81 ± 0.40 in patients with C2B >90 min, without significant differences between the two groups. At the time of discharge, a significant improvement of LVEF (from 41 ± 8% to 44 ± 9%, p = 0.013) and WMSI (from 1.78 ± 0.39 to 1.64 ± 0.38, p = 0.036) exclusively emerged in the ≤90 min group. Furthermore, we identified 37 patients who experienced, at the time of discharge, an improvement of the LVEF ≥10% compared to baseline values. In these patients the C2B time resulted significantly shorter, when compared with patients with LVEF improvement <10%: 42 min (IQR 18.5-77.5) vs. 104 (IQR 48-176), p < 0.0001. Additionally, these patients had lower significant levels of cardiac biomarkers. A significant improvement in WMSI was also observed in the ≥10% group (1,69 ± 0,41 vs 1,49 ± 0,41, p= 0.039). Conclusion Our study shows the immediate effects of an early revascularization. In particular, the duration of C2B time influences the recovery of ventricular function, in terms of ejection fraction and parietal kinetics. A standard TTE is a low cost and easily available examination, which may provide immediate results without impacting significantly on health costs.