Angiographic progression to total coronary occlusion in hyperlipidemic patients after acute myocardial infarction. POSCH Group.

The progression of coronary artery stenosis to total occlusion was assessed in 413 hyperlipidemic patients with a previous myocardial infarction. Coronary angiograms were recorded at baseline, 3 (n = 312), and 5 years (n = 248) after initial study and analyzed by 2 independent readers. There were 177 (43%) patients with 1-, 130 (31%) with 2-, and 61 (15%) with 3-vessel disease (greater than or equal to 50% diameter narrowing), whereas 45 (11%) did not have significant disease within a major coronary vessel at baseline. A new finding of total occlusion occurred in 4% (30 of 748) and 7% (40 of 605) of major coronary artery segments at 3 and 5 years, respectively. The risk of progression to total occlusion was higher if the initial stenosis was greater than 60% compared to lesions less than or equal to 60% both at 3 years (19 of 143 = 13% vs 11 of 605 = 2%; p less than 0.001) and 5 years (27 of 91 = 30% vs 13 of 514 = 3%; p less than 0.001). The frequency of occlusion was highest for the right coronary artery by 5 years (18 of 167 = 11% for right vs 8 of 225 = 4% for circumflex vs 14 of 213 = 7% for left anterior descending coronary arteries; p less than 0.02). Clinical and laboratory data revealed that myocardial infarction was associated with a new total occlusion in 23% of patients (7 of 30) at 3 years and in 64% (25 of 39) at 5 years.(ABSTRACT TRUNCATED AT 250 WORDS)

Pharmacokinetic characterization of the postdistribution phase of prohormone atrial natriuretic peptides amino acids 1-98, 31-67, and atrial natriuretic factor during and after rapid right ventricular pacing in dogs.

Release rate constants and disappearance rate constants were determined for three atrial natriuretic peptides consisting of amino acids 1-98 (i.e., proANF 1-98), the midportion of the ANF prohormone consisting of amino acids 31-67 (i.e., proANF 31-67) and amino acids 99-126 (i.e., ANF) after right ventricular pacing at 100, 125, 150, and 180 bpm in six male mongrel dogs. Right atrial and femoral vein blood was obtained at baseline, and at 5, 12, 19, 26, 56, 86, 116, 146, and 206 minutes after right ventricular pacing. Resulting plasma concentration-time data derived parameters were compared. The disappearance rate constants for atrial and femoral venous proANF 1-98 were 0.0144 +/- 0.0087 (X +/- SD) and 0.0175 +/- 0.0075 min-1, respectively (t = 0.6158) and release rate constants were 0.1569 +/- 0.1504 and 0.0670 +/- 0.0393 min-1, respectively (t = 1.8269; P greater than .05). The proANF 31-67 disappearance rate constants were 0.0139 +/- 0.0082 and 0.0148 +/- 0.0132 min-1, respectively (t = 0.1192) and release rate constants were 0.0957 +/- 0.0414 and 0.1984 +/- 0.1762 min-1, respectively (t = 1.4812). The ANF elimination phase disappearance rate constants were 0.0663 +/- 0.0273 and 0.1116 +/- 0.0539 min-1 (t = 2.0923, P greater than .05), respectively, and the release rate constants were 0.1335 +/- 0.0532 and 0.1638 +/- 0.0520 min-1 (t = 0.7878, P greater than .05), respectively. These data indicate that proANF 1-98 and proANF 31-67 circulating beta post-distribution half-lives are approximately 45 minutes whereas beta half-life of ANF is 10 minutes.(ABSTRACT TRUNCATED AT 250 WORDS)