Angiographic progression of coronary artery disease and the development of myocardial infarction

AbstractThere are few data on angiographic coronary artery anatomy in patients whose coronary artery disease progresses to myocardial infarction. In this retrospective analysis, progression of coronary artery disease between two cardiac catheterization procedures is described in 38 patients: 23 patients (Group I) who had a myocardial infarction between the two studies and 15 patients (Group II) who presented with one or more new total occlusions at the second study without sustaining an intervening infarction.In Group I the median percent stenosis on the initial angiogram of the artery related to the infarct at restudy was significantly less than the median percent stenosis of lesions that subsequently were the site of a new total occlusion in Group II (48 versus 73.5%, p < 0.05). In the infarctrelated artery in Group I, only 5 (22%) of 23 lesions were initially >70%, whereas in Group II, 11 (61%) of 18 lesions that progressed to total occlusion were initially >70% (p < 0.01). In Group I, patients who developed a Q wave infarction had less severe narrowing at initial angiography in the subsequent infarct-related artery (34%) than did patients who developed a non-Q wave infarction (80%) (p < 0.05). Univariate and multivariate analysis of angiographic and clinical characteristics present at initial angiography in Group I revealed proximal lesion location as the only significant predictor of evolution of lesions ≥ 50% to infarction.This irrespective study suggests that myocardial infarction frequently develops from previously nonsevere lesions. In addition, it is often difficult to predict the location of a subsequent infarct from analysis of the first coronary angiogram. Non-Q wave infarction is usually preceded by a more severe pre-existing stenosis than is a Q wave infarction, perhaps indicating some degree of prior myocardial protection. A prospective evaluation will be necessary to confirm these findings

Quantitative angiographic comparison of elastic recoil after coronary excimer laser-assisted balloon angioplasty and balloon angioplasty alone.

AbstractObjectives. Coronary lumen changes during and after excimer laser-assisted balloon angioplasty were measured by quantitative coronary angiography, and the results were compared with the effects of balloon angioplasty alone.Background. Reduction of atherosclerotic tissue mass by laser ablation in the treatment of coronary artery disease may be more effective in enlarging the lumen than balloon angioplasty alone.Methods. A series of 57 consecutive coronary lesions successfully treated by xenon chloride excimer laser-assisted balloon angioplasty were individually matched with 57 coronary artery lesions successfully treated by balloon angioplasty alone. The following variables were measured by quantitative coronary analysis: 1) ablation by laser, 2) stretch by balloon dilation, 3) elastic recoil, and 4) acute gain.Results. Matching by stenosis location, reference diameter and minimal lumen diameter resulted in two comparable groups of 57 lesions with identical baseline stenosis characteristics. Minimal lumen diameter before excimer laser-assisted balloon angioplasty and balloon angioplasty alone were (mean ± SD) 0.73 ± 0.44 and 0.74 ± 0.43 mm, respectively. Laser ablation significantly improved minimal lumen diameter by 0.56 ± 0.44 mm before adjunctive balloon dilation. In both treatment groups, similar-sized balloon catheters (2.59 ± 0.35 and 2.56 ± 0.40 mm, respectively) were used. After laser-assisted balloon angioplasty, elastic recoil was 0.84 ± 0.30 mm (32% of balloon size), which was identical to that after balloon angioplasty alone, namely, 0.82 ± 0.32 mm (32%). Consequently, both interventions resulted in similar acute gains of 1.02 ± 0.52 and 1.00 ± 0.56 mm, respectively. Minimal lumen diameter after intervention was equal in both groups: 1.75 ± 0.35 and 1.75 ± 0.34 mm, respectively. The statistical power of this study in which a 25% difference in elastic recoil (0.2 mm) between groups was considered clinically important was 95%.Conclusions. In matched groups of successfully treated coronary lesions, xenon chloride excimer laser ablation did not reduce immediate elastic recoil after adjunctive balloon dilation or improve the final angiographic outcome compared with balloon angioplasty alone using similar-sized balloon catheters

Cycling Induced Spontaneous Coronary Artery Dissection in a Healthy Male

Introduction. Spontaneous coronary artery dissection (SCAD) is a rare but important cause of acute coronary syndrome with a spectrum of disease that can include unstable angina, acute myocardial infarction, or sudden cardiac death. It has also been found in case reports to be caused by shear stress from physical exertion. We present a rare cycling induced SCAD that occurred in our institution in an otherwise healthy male with no cardiac risk factors. Case Presentation. A 36-year-old male presented to the emergency department with complaints of lightheadedness and diaphoresis after a bicycle fall. In the emergency department, he complained of feeling lightheaded and diaphoretic and having mid back pain. Patient had an ECG performed which showed lateral ST segment elevation and troponin I that was positive. A coronary angiography was subsequently performed demonstrating a spontaneous coronary artery dissection of left anterior descending coronary artery. Conclusion. SCAD is a rare cause of myocardial infarction, occurring in healthy individuals, which is rarely reported in the literature. Nearly 70% are diagnosed in postmortem studies after sudden cardiac death. Only 12 cases have been reported from activities involving physical exertion and no studies to our knowledge demonstrate this