Evert J.P. Lamfers

Abortion of acute ST segment elevation myocardial infarction after reperfusion: incidence, patients’ characteristics, and prognosis

Objectives: To study the incidence and patient characteristics of aborted myocardial infarction in both prehospital and in-hospital thrombolysis. Design: Retrospective, controlled, observational study. Setting: Two cities in the Netherlands, one with prehospital thrombolysis, one with in-hospital treatment. Patients: 475 patients with suspected acute ST elevation myocardial infarction treated before admission to hospital, 269 patients treated in hospital. Main outcome measures: Aborted myocardial infarction, defined as the combination of subsiding of cumulative ST segment elevation and depression to < 50% of the level at presentation, together with a rise of creatine kinase of less than twice the upper normal concentration. A stepwise regression analysis was used to test independent predictors for aborted myocardial infarction. Results: After correction for “unjustified” thrombolysis, 17.1% of the 468 prehospital treated patients and 4.5% of the 264 in-hospital treated patients fulfilled the criteria for aborted myocardial infarction. There was no difference in age, sex, risk factors, haemodynamic status, and infarct location of aborted myocardial infarction compared with established myocardial infarction. Time to treatment was shorter in the patients with aborted myocardial infarction (86 versus 123 minutes, p = 0.05). A shorter time to treatment, lower ST elevation at presentation, and higher incidence of preinfarction angina were independent predictors for aborted myocardial infarction. Aborted myocardial infarction had a 12 month mortality of 2.2%, significantly less than the 11.6% of established myocardial infarction. Conclusion: Prehospital thrombolysis is associated with a fourfold increase of aborted myocardial infarction compared with in-hospital treatment. A shorter time to treatment, a lower ST elevation, and a higher incidence of preinfarction angina were predictors of aborted myocardial infarction.

Effect of prehospital thrombolysis on aborting acute myocardial infarction

On administering thrombolysis in a prehospital setting, we found a threefold increase in the incidence of abortion of myocardial infarction, compared with the in-hospital program of a nearby hospital. Assessment of aborted myocardial infarction may be a better criterion for the efficacy of early thrombolysis than mortality data.

Atrial natriuretic peptide after myocardial infarction

Plasma concentrations of atrial natriuretic peptide (ANP) after acute myocardial infarction were measured at fixed times during 48 hours in 38 patients admitted to the hospital within 4.4 hours after the onset of symptoms. Three hours after admission, the mean concentration of ANP was significantly lower than that at the time of admission. Thereafter it rose steadily until 15 hours after admission. ANP concentrations measured in each patient at the time of admission and the individual mean ANP concentrations during the first 48 hours after admission correlated weakly but significantly with the size of the infarct and the left ventricular function. Neither the site of the infarct, the occurrence of reperfusion, nor the number of coronary vessels affected influenced the ANP concentration. In 24 patients in whom cardiac catheterization was performed, no relationship between ANP concentrations and left ventricular pressures was observed. Determination of ANP concentrations seems to be of little value in assessing cardiac function after acute myocardial infarction.

Prehospital thrombolysis with reteplase: the Nijmegen/Rotterdam study.

OBJECTIVE The objective of this observational study was to assess time from electrocardiogram diagnosis to treatment and time from pain onset to treatment with double bolus reteplase compared to current therapy with streptokinase or bolus anistreplase in 2 cities (Rotterdam and Nijmegen) in the Netherlands, where prehospital thrombolysis is an established way of treatment of acute myocardial infarction. METHODS Prehospital thrombolysis is performed using electrocardiogram diagnosis by the ambulance service as well as bolus anistreplase for treatment in Nijmegen, and streptokinase infusion in Rotterdam. Reteplase or anistreplase/streptokinase was assigned open label to patients according to order of presentation on a 1-to-1 basis. All patients were treated with nitrates sublingually and aspirin orally. Time intervals were recorded by the ambulance staff. RESULTS In total, 250 patients were treated between April 1, 1999 and August 1, 2000. Reteplase was used in 120 patients and anistreplase/streptokinase in 130 patients. Using double bolus reteplase resulted in a significantly shorter time to treatment: a median of 81 minutes compared to a median of 104 minutes with the established therapy (P <.0001). There were no differences in mortality, aborted myocardial infarction, hemorrhagic stroke or the need for rescue angioplasty between the groups. CONCLUSION In prehospital thrombolysis, double bolus reteplase is associated with a shorter time to treatment than bolus anistreplase or infusion of streptokinase.

Plasma atrial natriuretic peptide in patients with acute myocardial infarction: effects of streptokinase.

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Influence of Time to Treatment Interval on Myocardial Salvage in Patients With Acute Myocardial Infarction Treated With Coronary Artery Stenting or Thrombolysis

To the Editor: Schomig et al1 report an elegant study on the effect of thrombolysis or primary angioplasty on myocardial salvage in acute ST-elevation myocardial infarction. Their conclusion is that stenting is preferred over thrombolysis regarding salvage of myocardium. However, their methods raise several questions. First, why are time intervals chosen according to the tertiles of the time-to-treatment intervals, 165 minutes (2 hours and 35 minutes) and 280 minutes (4 hours and 40 minutes)? Why not choose time intervals of 1:00, 2:00 and 3:00 hours, as in the Global Utilization of Streptokinase and Tissue Plasminogen Activator for Occluded Coronary Arteries (GUSTO)-1 study? Choosing 165 minutes can be interpreted as there being too few patients treated within 2 hours after onset of pain to perform a statistical analysis. Secondly, in patients treated with stenting, the time-to-treatment interval was …