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Background: We investigated the possibility that transient coronary slow-flow as assessed during coronary angiography in patients with cardiac syndrome X may impair myocardial perfusion and the effects of this phenomenon on long-term prognosis. Methods: From 50 consecutive patients with cardiac syndrome X, we prospectively recruited 16 who exhibited coronary slow-flow during angiography. The remaining 34 patients served as controls. The slow-flow phenomenon was invariably worsened by nitrates and reversed by papaverine. During slow-flow, a dose of 99m-Tc-Methoxy-isobutyl-isonitrile (MIBI) was injected in 12 patients and SPECT imaging performed 1 h later. The perfusion study was repeated after 2 days at rest and, in 9 patients, at peak exercise after 10 +/- 4 days. Patients were then regularly followed-up. Results: All 12 patients had a significant MIBI defect in the regions served by the coronary artery that showed slow-flow just prior MIBI injection. After exercise, MIBI tomograms revealed a perfusion defect in 5 out of the 9 patients who underwent stress scanning. At 14 +/- 2 years follow-up, 1 patient with slow-flow had died and 4 developed significant coronary artery disease (CAD), while all patients of the control group were alive and none had developed significant CAD. Conclusions: These results show that the slow-flow phenomenon might be the cause of transient myocardial underperfusion in patients with angina and normal coronary arteries. Apparently, this phenomenon is associated with a worse cardiac prognosis. Therefore, patients with coronary slow-flow should be carefully followed-up. (C) 2008 Elsevier Ireland Ltd. All rights reserved.

OBJECTIVES We assessed the short- and long-term clinical and angiographic outcome of nonocclusive unstented dissection after percutaneous transluminal coronary angioplasty (PTCA) and its correlation with restenosis. BACKGROUND The use of stents has dramatically increased both the number and the cost of coronary revascularization procedures. However, this technique is not completely risk free, and its benefits have not been fully demonstrated in uncomplicated dissections. METHODS We studied 129 consecutive patients with 49 nonocclusive dissections after PTCA (grades A to D of National Heart, Lung, and Blood Institute classification) and good distal Asw (TIMI [Thrombolysis in Myocatdial Infarction] flow grade 3). All patients underwent coronary angiography at 24 h and at six months past-PTCA. Clinical status was assessed every three months in the outpatient clinic. Study subjects were matched with 60 other patients in whom stenting was performed for the presence of dissection. RESULTS In the former group, all but two patients (with type E dissection, which evolved to coronary occlusion and myocardial infarction) improved their dissection score during follow-up: at six months only 18 dissections were still angiographically visible, and no clinical adverse events were recorded. In the dissected vessels, the restenosis rate was significantly lower than in those without dissection (12% vs. 44%, p < 0.001); in the stented vessels, the restenosis rate was 25% (15/60). CONCLUSIONS In the presence of TIMI flow grade 3, coronary dissection is associated with a favorable outcome and predicts a low restenosis rate. These results caution against the indiscriminate use of intravascular prostheses in the event of nonocclusive coronary dissection. (C) 1999 by the American College of Cardiology.

Objectives. This study sought to investigate whether residual viability of infarcted myocardium may play a role in the pathogenesis of exercise-induced ventricular arrhythmias. Background. We previously showed that transient ischemia within partially infarcted areas often precipitates ventricular arrhythmias during exercise that are consistently obliterated by intravenous nitrates. Methods. We studied 60 patients with chronic stable angina and a previous myocardial infarction, All underwent at least two consecutive exercise stress tests, coronary angiography and stress/rest myocardial perfusion tomography by Tc-99m 2-methoxy isobutyl isonitrile (MIBI). In the last 26 consecutive patients, residual viability was assessed by single-photon emission computed tomography (SPECT) using fluorine (F)-18 fluorodeoxyglucose. Perfusion and metabolic data were evaluated qualitatively by three independent observers in blinded manner, Results. With exercise, 30 patients (group A) consistently developed ventricular arrhythmias (>10 ventricular ectopic beats/min, couplets, nonsustained ventricular tachycardia); the remaining 30 patients (group B) did not, The severity of coronary artery disease (Gensini score) was similar in the two groups. Posterercise SPECT shun ed partial reperfusion of an infarcted area in 28 of 30 patients of group A but in only 9 of 30 of group B (p < 0.0001). Uptake of F-18 fluorodeoxyglucose was observed within the infarcted zone in 10 of 13 and 1 of 13 patients in groups A and B, respectively (p = 0.0003). Conclusions. In patients with myocardial infarction, exercise-induced ventricular arrhythmias appear to be triggered by transient ischemia occurring within a partially necrotic area containing large amounts of viable myocardium. Therefore, occurrence of arrhythmias during exercise may represent a clue to the presence of residual viability within a previously infarcted area. RI Lucignani, Giovanni/C-6773-2008

Thirteen hypertensive patients with microvascular angina were studied before and after receiving oral L-arginine (4 weeks, 2 g, 3 times daily). L-arginine significantly improved angina class, systolic blood pressure at rest, and quality of life. Maximal forearm blood flow, plasma L-arginine, L-arginine:asymmetric dimethyl arginine ratio, and cyclic guanylate monophosphate increased significantly after treatment. In medically treated hypertensive patients with microvascular angina, oral L-arginine may represent a useful therapeutic option. (C) 2004 by Excerpta Medica, Inc.