Karl Wegscheider

Extent of Early ST Segment Elevation Resolution: A Simple but Strong Predictor of Outcome in Patients With Acute Myocardial Infarction

OBJECTIVES This study proposed to verify the prognostic power of early ST segment elevation resolution in patients with acute myocardial infarction from the Intravenous Streptokinase in Acute Myocardial Infarction study data base. BACKGROUND Data from a small prospective study suggested that use of two cutoff points for three different levels of ST segment resolution 3 h after the start of thrombolysis may be an efficient way to predict outcome in an individual patient. METHODS The three groups of ST segment resolution were defined as 1) complete resolution (> or = 70% [552 patients]) or only slight ST segment elevation (127 patients); 2) partial resolution (< 70% to 30% [475 patients]); 3) no resolution (< 30% to > 0% [362 patients]). Infarct size was measured from creatine kinase isoenzyme, MB fraction, release and from the number of Q waves. Left ventricular function was assessed in 818 patients 1 month after infarction. RESULTS For complete, partial and no ST segment resolution 3 h after the start of streptokinase or placebo infusion, enzyme release was 1.2, 1.8 and 2.1 IU/ml x h; number of Q waves 1.7, 2.5 and 3.0; and ejection fraction 60%, 53% and 49%, respectively (all adjusted p = 0.0000). Mortality rate at 21 days was 2.2%, 3.4% and 8.6%, respectively. No ST segment resolution was the most powerful independent predictor of early mortality (p = 0.0001). Survival rate curves at 6-year follow-up showed significant mortality differences with increasing divergence (p = 0.0003 anterior infarction; p = 0.005 inferior infarction). In subgroups with an overall higher risk of dying, mortality was strongly determined by the extent of early ST segment resolution. CONCLUSIONS The extent of ST segment elevation resolution conveys useful early information about outcome in an individual patient after acute myocardial infarction.

Intravenous short-term infusion of streptokinase in acute myocardial infarction.

Short-term i.v. infusion of streptokinase was performed in 93 patients within 6 hours after the onset of acute myocardial infarction. Twenty-six patients underwent angiography in the acute phase (group A) and 52 underwent angiography in the fourth week only (group B); 15 patients had no angiography. Seven patients died during the hospital stay and six suffered nonfatal reinfarctions. There were no bleeding complications. In 11 of 21 group A patients, occluded coronary arteries were opened within 1 hour after the streptokinase infusion was started. In 84% of groups A and B, the infarct-related coronary artery was patent in the fourth week. In 75% of the patent arteries, the residual luminal diameter stenosis was less than 70%. According to serial serum CK-MB curves, recanalization was achieved mostly within 1–2 hours. Myocardial salvage was indicated by improvement in local contraction disorders in the recanalized group A patients and by the significant relationship between infarct size and time from symptom onset to treatment in group B. These data suggest that a high-dose, short-term, i.v. infusion of streptokinase is a safe and efficient method of restoring coronary blood flow. Expeditious initiation of i.v. streptokinase infusion is a critical determinant for early recanalization and salvage of myocardium. Patients with thrombotically subtotal occlusion probably receive the most benefit. Evaluation of the true impact on survival and myocardial function will require controlled clinical trials.

Prophylaxis of Constipation by Wheat Bran: A Randomized Study in Hospitalized Patients

To evaluate the efficacy of wheat bran in preventing constipation, 200 hospitalized patients were randomly allocated to groups receiving either a dietary supplement of 40 g bran daily or no dietary supplement at all. A quarter of the bran group patients refused to take their bran from the very beginning (refusers), one third stopped bran consumption during the study (dropouts), and only 42% of the patients continued on bran until discharge or death (participants). Independent of a previous history of constipation, neither the hospital incidence of constipation nor the average percentage of days on laxatives was significantly different between the bran group and the control group. Only the dropouts were significantly more constipated than the control patients, whereas no such difference could be demonstrated in the refusers or participants. It is concluded that the administration of bran as a prophylactic laxative confers no benefit in patients hospitalized for a relatively short time.

Follow-up of prostaglandin plasma levels after acute myocardial infarction

Prostaglandin plasma levels are elevated in patients with transient myocardial ischemia. We measured 6-keto-prostaglandin F1 alpha (6-keto-PGF1 alpha) and thromboxane (B2(TXB2) in venous blood of 32 patients with myocardial infarction on the first, third, and seventh days. TXB2 and 6-keto-PGF1 alpha levels in these patients (up to 117 +/- 237 pg/ml and 96 +/- 105 pg/ml mean +/- SD, respectively) differed significantly from levels in normal control subjects (10 +/- 12 pg/ml and 4 +/- 7 pg/ml mean +/- SD, respectively) (p less than 0.01). Prostaglandin values remained elevated from day 1 through day 7. In most patients, 6-keto-PGF1 alpha levels prevailed over those of TXB2. In a subgroup suffering from cardiac arrhythmias, the ratio of 6-keto-PGF1 alpha/TXB2 was inverse. It is concluded that prostaglandin generation is increased for at least 7 days after myocardial infarction. A disturbed ratio of 6-keto-PGF1 alpha/TXB2 in favor of the latter might be associated with cardiac arrhythmias in myocardial infarction.

994-95 Variability Sources in Quantitative Coronary Arteriography

In a trial of progression/regression of coronary artery disease the results of quantitative coronary arteriography are affected by the following main factors: (i) the frame selected for analysis (FRAME), according to the general agreement, that the lesion should be measured at enddiastole. (ii) the frame rate (RATE), To obtain a truely enddiastolic image of a coronary lesion, a cine frame rate of 25 frames/sec is mandatory up to date. Newer digital equipped systems allow to use a frame rate of 12.5/sec, but there is concern, that one miss a truely representative enddiastolic image. (iii) the measurement variance (MEAS) obtained from repeated measurements. We analyzed the impact of these variability sources on the measurements in a study of 29 coronary lesions. The lesions were filmed at 25 and 12.5 frames/sec. The truely enddiastolic frame as well as the frame preceeding and following it was analyzed. Each frame was measured twice, using computer-assisted analysis of vessels. A nested multivariate analysis of variance was developed to quantify the effects of the independent variables RATE (12.5 instead of 25/sec), FRAME (enddiastole or a frame deviating from it) and MEAS (measuring the same frame twice) on the “outcome” in the sample the mean % diameter stenosis. The total variance in the sample by considering different stenosis (STEN; 15–75% diameter stenosis) was set to 100%. Results Multivariate analysis of variance shows the following influence of the various components on the size of % diameter stenosis: Independent variable STEN FRAME RATE MEAS Coefficient of variation 23.67 9.23 4.38 5.70 % contribution to total variance 100 15.20 3.40 5.90 Conclusions Frame selection is the major source of variability quantifying coronary lesions. Compared to the total variance the variance attributable to frame selection is nearly 3 times higher than the measurement variance and nearly 5 times higher than the rate attributable variance. Thus, one hasto take great care of selecting appropriate frames and may use the lower frame rate (12.5/sec) to reduce radiation exposure and facilitate digital image archiving.

New method for the assessment of drug-induced arrhythmia aggravation

Abstract That antiarrhythmic drugs may aggravate or induce arrhythmias is a common clinical observation and has also been documented by several investigations.1–3 Efforts to establish a definition of proarrhythmic drug effect by means of quantitative registration of arrhythmias have not been conclusive and, so far, proarrhythmia has been defined arbitrarily.4,5 The aim of the present study was to develop a statistical model enabling us to differentiate an antiarrhythmic-induced increase of arrhythmias from spontaneous arrhythmic variations.