ST-segment re-elevation following primary angioplasty in acute myocardial infarction with patent infarct-related artery: impact on left ventricular function recovery and remodeling

Introduction
Spontaneous recanalization of the infarct-related artery (IRA) in ST-segment elevation myocardial infarction (STEMI) before primary angioplasty (PCI) improves clinical outcomes.

Aim
To investigate the impact of ST-segment re-elevation (reSTE) following PCI in patent IRA on left ventricular (LV) function recovery and remodeling.

Material and methods
Of 155 STEMI patients with patent IRA, 19 (12.3%) patients with TIMI-2 (T2_Res) and 85 (54.8%) with TIMI-3 (T3_Res) had further STE resolution following PCI, 20 (12.9%) with TIMI-3 did not require PCI (T3_noPCI) and 31 (20.0%) with TIMI-2/3 had reSTE of ≥ 1 mm following PCI as compared with pre-PCI recordings (T23_reSTE). LV ejection fraction (LVEF, %) and LV end-diastolic and end-systolic volume indexes (LVEDVI, LVESVI, ml/m2) were measured by echocardiography 2 days and 6 months following PCI.

Results
In 6-month observation the improvement of LVEF in T3_Res (by 3.9 ±5.1%) and in T3_noPCI (by 5.7 ±6.1%) patients was higher as compared with T23_reSTE (0.2 ±7.0%, p < 0.05 versus both). LVEDVI increased in T23_reSTE patients by 6.6 ±12.6 ml/m2, but decreased in T3_Res by 3.8 ±9.7 ml/m2 and in T3_noPCI by 2.4 ±6.2 ml/m2 (for both p < 0.05 vs. T23_reSTE). LVESVI increased in T23_reSTE patients (by 3.8 ±10.8 ml/m2), did not change in T2_Res (by 0.1 ±9.0 ml/m2), but decreased in T3_Res (by 4.2 ±7.2 ml/m2, p < 0.05 vs. T23_reSTE) and in T3_noPCI patients (by 4.7 ±7.7 ml/m2, p < 0.05 vs. T23_reSTE). ReSTE was an independent predictor of LVEF, LVEDVI and LVESVI changes (p < 0.001 for all).

Conclusions
ReSTE following PCI in a patent IRA is associated with a lack of improvement of LV contractility and subsequent LV remodeling.