Factors that determine recovery of left ventricular function after thrombolysis in patients with acute myocardial infarction.

Abstract

The coronary and ventricular angiograms of 47 patients with acute myocardial infarction in whom reperfusion was achieved by intracoronary streptokinase were quantitatively analyzed to determine the factors that affect recovery of regional left ventricular function after reperfusion. Hypokinesis in the infarct region was measured by the centerline method and expressed in terms of standard deviations (SDs) from normal. Severity of coronary artery stenosis was measured quantitatively. Hypokinesis showed more significant improvement after thrombolysis in patients with minimum stenosis diameter of greater than 0.4 mm than in those with severe residual stenosis, i.e., stenosis producing a minimum diameter of 0.4 mm or less (1.0 + 1.3 SD/chord, n = 31, vs 0.0 + 0.9 SD/chord, n = 7; p < .05). Improvement in hypokinesis was greater in patients who received thrombolytic therapy within 2 hr than in those treated later (2.1 ± 1 1, n = 8, vs 0.7 + 1.0 SD/chord, n = 28; p < .001). These results indicate that angiographic reperfusion alone may not be sufficient: reperfusion must provide adequate flow and be achieved early to salvage myocardial function. Circulation 71, No. 6, 1121No. 6, -1128No. 6, , 1985 THERE HAVE BEEN many studies of the efficacy of thrombolytic therapy in achieving reperfusion, salvaging myocardial function, and reducing mortality. However, the reported efficacy of streptokinase, the most frequently used agent, in reducing mortality has varied widely in several randomized trials.'-' Randomized studies measuring change in the ejection fraction, a powerful predictor of survival,4 have also had conflicting results.3' 1-One reason is that the ejection fraction may not sensitively reflect changes in regional function at the infarct site because of the influence of compensatory hyperkinesis of the noninfarcted region.Y, 9However, even when regional function was measured, significantly improved function was observed in only 40% of patients with angiographically proven sustained reperfusion,' indicating that factors other than achievement of reperfusion affect the recovery of left ventricular function. The present study was performed to determine the effect of the following factors on recovery of regional left ventricular wall motion in patients undergoing reperfusion: (1) the time delay from onset of chest pain to reperfusion, (2) the severity of residual stenosis at the conclusion of thrombolytic therapy, (3) the severity of acute left ventricular dysfunction, (4) the location and severity of the acute occlusion, and (5) the time from infarction to follow-up study. Materials and methodsPatient populations. The effect of acute severity of functionã l abnormality, location of thrombosis, and residual stenosis was studied in previously reported patients8 in whom reperfusion was achieved with intracoronary streptokinase therapy. All patients were admitted to the Eppendorf Hospital less than 3 hr after onset of chest pain that was unresponsive to sublingual nitroglycerin and all had 2 mm or greater ST segm...

Augmented and sustained plasma concentrations after intramuscular injections of molecular variants and deglycosylated forms of tissue-type plasminogen activators.

“…Later phenomena manifested in the plasma time-concentration curve would be anticipated to reflect the (3-phase rate constant of disappearance and the impact of interactions between the activator and circulating inhibitors affecting clearance in vivo as well. As judged from comparisons of plasma time-concentration curves of wild-type t-PA and five different species of t-PA (deglycosylated wild-type t-PA and genetically engineered variants [1][2][3][4], prolongation of the a-phase of clearance was associated with alterations of plasma time-concentration curves after intramuscular injections resulting in higher and more sustained early peaks.…”

Exercise-induced T-wave normalization predicts recovery of regional contractile function after anterior myocardial infarction

“…In reperfused myocardium, the persistence of a reduced flow across a high grade residual stenosis could cause persistent ischaemia or hibernation and limit functional recovery [44,45] . In our study, we elected to revascularize all patients exhibiting significant residual stenosis, in an attempt to reduce the effects of residual ischaemia on left ventricular function.…”

Predischarge low‐dose dobutamine test and prediction of left ventricular function at 1 year in patients with a first anterior myocardial infarction

“…[1][2][3][4] Some investigators consider that viability seems to be more frequently present in patients with a rather preserved left ventricular (LV) function following AMI, 1 while others have suggested that those with more compromised function are more likely to improve over time. [2][3][4] In the present study, we attempted to gain further insight into the relationship between the predischarge status of LV function and the changes observed at 1 year in patients with a first anterior ST-elevation AMI following conventional management. Moreover, we also investigated the role of predischarge isotopic ventriculography with a low-dose dobutamine test (DBT) in predicting changes in LV ejection fraction (LVEF), regional contractility score (RCS), and LV end-diastolic volume index (EDVI) at 1 year.…”