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Although several studies have investigated ventricular (LV) function after reperfusion interventions, it is still unclear whether benefits result from successful therapy or whether such benefits only reflect the natural history of a subgroup of patients with acute myocardial infarction (AMI). This study evaluates the unique effect of thrombolytic therapy on the natural history of regional LV wall motion dysfunction. One hundred seventy-six patients with AMI were studied: 82 patients (group A) underwent conventional treatment and 94 (group B) thrombolytic therapy. LV regional improvement, evaluated by changes in echo score between admission and predischarge examination, was present more frequently in group B (28%) than in group A (17%). Furthermore, improve patients in group B had higher admission echo scores (7.5 [+ or -] 3.5 vs 6.3 [+ or -] 3.1), a prevalence of anterior AMI (68 vs 30.1%) and a higher rate of coronary patency (92 vs 58% in patients who had no improvement). In group A patients the rate of coronary patency was similar in those who did (46.1%) and did not have (36.1%) improvement. Observations at 12 to 18 months showed similar data in group A patients and in group B patients without improvement, marginal additional improvement was observed in group B patients who had in-hospital improvement. These observations demonstrate that LV function recovery is more frequent and marked in treated than in untreated patients. Follow-up results suggest a prolonged beneficial effect of thrombolytic treatment on LV function. The highest rate of coronary patency in improved group B patients underline the role of reperfusion natural history of LV dysfunction after AMI. (Am J Cardiol 1993;71:1015-1020)

By using a highly sensitive, high-performance liquid chromotographic technique, plasma values of malondialdehyde (MDA), adenosine and oxypurines were determined in 10 healthy subjects, 10 patients with noncardiac illness, and 20 patients with acute myocardial infarction (AMI) observed within 6 hours from the onset of symptoms. Patients with AMI received fibrinolytic treatment. Penpheral Mood was obtained before and serially after thrombolysis (1, 2, 3, 6 and 24 hears). Coronery patency was assessed by timing of peak creatine phosphate kinasu and by predischarge angiography. MDA (mean [+ or -] SD) in healthy subjects, noncardiac patients, and immediately before thrombolytic treatment in patients with AMI was 0.051 [+ or -] 0.013, 0.066 [+ or -] 0.020 and 0.397 [+ or -] 0.326 [micro]mol/liter of plasma, respectively. A progressive increase in plasma MDA after thrombolysis was observed only in reperfused patients, whose values at the third, sixth and 24th hours were also significantly greater than those of nonreperfused patients. Time-dependent variations of xanthine and adenosine were also observed in the same group after thrombolysis. The data appear to indicate that a relevant increase in plasma MDA, mostly originating due to phospholipid derangement of postischemic myocytes, occurs only in patients with successful thrombolysis, thus suggesting that if propedy assayed, it may represent reliable biechemical evidence of tissue injuries after myocardial reperfusion in humans. (Am J Cardiol 1993;71:788-793)

Two-dimensional and Doppler echocardiographic studies and a hemodynamic investigation were performed during dipyridamole testing in 42 subjects (13 control subjects and 29 patients with coronary artery disease [CAD]), to evaluate the ability of dipyridamole Doppler echocardlography in identifying patients with ischemic left ventricular dysfunction. in the control group, after dipyridamole infusion, Doppler-derived parameters increased significantly from baseline (p (Am J Cardiol 1990;65:829-834), One method of assessing the health of the coronary arteries (the arteries that deliver blood to the heart tissue itself) is a noninvasive approach called Doppler echocardiography, an ultrasound technique that provides an image of the beating heart and its blood flow. Since ischemia (decreased blood flow) is a consequence of coronary artery disease, testing should determine if blood flow in these arteries is normal. It is possible that injection of an agent that causes vasodilation (enlargement of the blood vessels), combined with Doppler echocardiography, would constitute a useful diagnostic approach. This method was tested in 42 subjects who underwent diagnostic coronary angiography (injection of a dye into the coronary arteries, followed by X-ray pictures of the dye in the vessels) because they had experienced a chest pain syndrome. Thirteen patients had normal coronary arteries and constituted the control group; the rest had coronary artery disease of at least one coronary artery. All patients received dipyridamole (a vasodilator) intravenously and heart rate, blood pressure, and electrocardiographic variables were monitored continuously. Doppler and two-dimensional echocardiography (an ultrasound technique that allows measurement of other aspects of coronary function) were also performed, as were measurements of hemodynamic variables such as pressure in the chambers of the heart. The results showed that measurements obtained with Doppler echocardiography increased for control subjects after dipyramidole was administered, but certain variables did not change in patients with coronary artery disease. The measures that remained constant were peak flow velocity (velocity of blood flow at the point in the cycle of maximum output), flow velocity integral, and stroke volume (the amount of blood pumped with one contraction). Heart rate and most other measures remained the same in both groups before and after dipyridamole. The changes noted in patients with coronary artery disease appear to be the result of ischemia of the heart muscle. It therefore appears that Doppler echocardiography can be used to distinguish certain patients with heart disease from normal subjects. Limitations of the method are discussed. (Consumer Summary produced by Reliance Medical Information, Inc.)