Abstract
Background: Considerable parts of the myocardium fall into myocardial stunning just after reperfusion therapy for acute myocardial infarction (AMI). In the present study, the prediction of recovery from myocardial stunning by the change in the stroke volume (SV) with a Swan-Ganz catheter (Stroke Volume with Swan-Ganz, SGSV) just after reperfusion therapy was attempted. Methods: The study consisted of 35 consecutive patients transferred to the Emergency Center of Kitasato University Hospital with a first uncomplicated anteroseptal AMI. Primary percutaneus transluminal coronary angioplasty (primary PTCA) for left anterior descending artery (LAD) was performed in 32 patients. They were divided into a stroke volume-increasing group (SGSV-UP group) or decreasing group (SGSV-DOWN group) according to their SGSV change during the CCU stay. The ejection fraction (EF) and SV on left ventriculography (LVG) (EF on LVG, LVGEF; SV on LVG, LVGSV) in the acute and chronic phase (about 6-8 months later) were compared between the two groups. Results: Twenty four patients were classified into the SGSV-UP group and 8 patients into the SGSV-DOWN group. LVGEF increased significantly in the SGSV-UP group but not in the SGSV-DOWN group (from 40.8±8.5% to 54.1±9.1%, P=0.0022 vs. from 42.2±10.6% to 43.6±7.7%, N. S.). LVGSV changed similar to LVGEF. In the SGSV-UP group, the relationship between the change in LVGEF (Δ LVGEF) and SGSV (Δ SGSV) was revealed to be Δ LVGEF (%)=1.4+0.5 Δ SGSV (ml) (P=0.0082). Regional asvnergy was significantly reduced in the SGSV-UP group (P=0.034). Conclusion: The increase in SGSV just after reperfusion therapy for AMI was related to the recovery of LVGEF and LVGSV in the chronic-phase. This suggests that recovery from myocardial stunning begins just after reperfusion therapy for AMI.
