Non-culprit Stenosis Research Articles

Geometric features of coronary artery lesions favoring acute occlusion and myocardial infarction: a quantitative angiographic study

OBJECTIVESWe sought to identify the angiographic predictors of a future infarction, to study their interaction with time to infarction, patient risk factors and medications, and to evaluate their clinical utility for risk stratification.BACKGROUNDIdentification of coronary lesions at risk of acute occlusion remains challenging. Stenosis severity is poorly predictive but other stenosis descriptors might be better predictors.METHODSEighty-four patients with an acute myocardial infarction and a coronary angiogram performed within the preceding 36 months (baseline angiogram), and after infarction were selected. All coronary stenoses (from 10% to 95% lumen diameter reduction) at baseline angiogram were analyzed by computer-assisted quantification. Each of the 84 lesions responsible for the infarction (culprit) was compared with the nonculprit stenoses (controls) in the same patient.RESULTSCulprit lesions were more symmetrical (symmetry index +15%; p < 0.001), had steeper outflow angles (maximal angle +4°; p < 0.001), were more severe (percent stenosis +5%; p = 0.001) and longer (+1.5 mm, p = 0.01) than controls. The symmetry index and the outflow angles were the two independent predictors of infarction at three-year follow-up. Stenosis severity predicted only infarctions occurring within 1 year after angiography. In moderately severe stenoses (40% to 70% stenosis), stratification using the symmetry index and outflow angles accurately predicted lesions remaining free of occlusion and infarction at three-year follow-up.CONCLUSIONSBetter characterization of stenosis geometry might help to understand the pathophysiologic mechanisms triggering coronary occlusion and to stratify patients for improved care.

Differential progression of complex culprit stenoses in patients with stable and unstable angina pectoris

Objectives. This study sought to compare the evolution of complex culprit stenoses in patients with stable and those with unstable angina pectoris.Background. Complex coronary stenoses are associated with adverse clinical and angiographic outcomes. However, it is not known whether the evolution of complex stenoses differs in unstable angina versus stable angina pectoris.Methods. We prospectively assessed stenosis progression in 95 patients with unstable angina whose angina stabilized with medical therapy (Group 1) and 200 patients presenting with stable angina (Group 2). After diagnostic angiography, all patients were placed on a waiting list for coronary angioplasty and restudied at 8 ± 4 (mean ± SD) months later. In each patient the presumed culprit stenosis was identified and classified as complex (irregular borders, overhanging edges or thrombus) or smooth (absence of complex features). Stenosis progression, as assessed by computerized angiography, was defined as ⩾20% diameter reduction or new total occlusion.Results. At the first angiogram, 364 stenoses ⩾50% and 383 stenoses <50% were identified. At restudy, 36 (15%) of 236 stenoses progressed in 29 Group 1 patients and 36 (7%) of 502 stenoses in 31 Group 2 patients (p = 0.001). Forty-five (88%) of 51 stenoses ⩾50% and 6 (29%) of 21 stenoses <50% that nitrogeressed developed to total coronary occlusion (p = 0.001). More culprit stenoses progressed in Group 1 than in Group 2 (p = 0.006), whereas progression of nonculprit stenoses was not significantly different in both groups. Culprit complex stenoses progressed more frequently in Group 1 than in Group 2 (p = 0.01). During follow-up, 3 patients died (myocardial infarction), and 51 had a nonfatal coronary event. Culprit steenoses progressed in 15 (54%) of the 28 patients with a nonfatal coronary event in Group 1 and in 9 (39%) of 23 patients in Group 2 (p = NS). Complex morphology (p < 0.001) and unstable angina at initial presentation (p < 0.01) were predictive factors for progression of culprit stenoses.Conclusions. A larges proportion of culprit complex stenoses progress in unstable angina than stable angina, and this is frequently associated with recurrence of coronary events.