86,658 research outputs found
Free malondialdehyde (F-MDA): a plasmatic marker of clinical instability in coronary artery disease
No full textBackground: Macrophage derived proteolytic enzymes induce collagen catabolism, resulting in a weakened fibrous cap of coronary atherosclerotic plaques. The subsequent ulceration and endoluminal thrombosis may lead to unstable angina and myocardial infarction. Futhermore, macrophage activation is followed by the release of oxigen free radicals whose activity may be monitored by plasmatic concentration of free-malondialdehyde (F-MDA). Elevated F-MDA values are considered suggestive of a rising rate of macrophage-mediated lipid peroxidation. v Aim: To evaluate F-MDA as a marker of macrophage activation and, then, of plaque and clinical instability. Methods: We enrolled 15 pts with stable angina (SA), 22 with unstable angina (UA) and 12 with myocardial infarction (AMI). Patients were well-matched for age, sex and coronary risk factors. F-MDA was assessed by gas chromatography-mass spectrometry Data were analysed using Wilcoxon test and χ2 test. Results: F-MDA was significantly higher in patients with UA and AMI when compared with SA group (0.58μM and 0.65μM vs 0.31μM, as median values p<0.01). F-MDA was over the normal range (0-0.35μM) in 4 pts with SA (26%), 17 with UA (77%) and 9 with AMI (75%) (p<0.02). No relation was found between F-MDA concentration and lipids, CRP and ESR. (Graph Presented) Conclusions: Our study shows the "in vivo" role of activated macrophages in acute coronary syndromes. F-MDA might be useful to identify patients at risk of instabilisation
Progressive growth of coronary aneurysms after bioresorbable vascular scaffold implantation: Successful treatment with OCT-guided exclusion using covered stents
No full textThe development and progressive enlargement over time of multiple saccular coronary artery aneurysms (CAA) after implantation of everolimus-eluting stent and bioresorbable vascular scaffolds (BVS) have been reported. CAA was successfully excluded by two overlapped covered stents expanded inside a long metallic drug-eluting stent to avoid dislodgment at the overlap point. Optical coherence tomography (OCT) was repeatedly performed to monitor CAA expansion and to guide treatment through precise measurement of aneurysm length and vessel size at the landing zone. At 10-month follow-up, coronary computed tomography angiography showed persistent CAA exclusion. To the best of our knowledge, this is the first report of this technique to exclude a long CCA segment
Seven-year recurrence of left ventricular apical ballooning
No full textLeft ventricular apical ballooning (Tako-tsubo syndrome) is an acute and rapidly reversible dysfunction of the left ventricle, triggered by a profound psychological stress. We describe an interesting case of very late recurrence
Emergency stenting of totally occluded left main coronary artery in acute myocardial infarction
No full textWe report a case of emergency stenting for acute occlusion of the left main coronary artery in the setting of acute myocardial infarction. Although stent implantation allowed prompt revascularization and successful immediate management of this life-threatening condition, subacute stent thrombosis occurred, requiring re-PTCA followed by surgical revascularization. This case suggests that stenting of an acutely occluded left main coronary artery may be a life-saving procedure but should only be used as a bridge to surgery rather than a definitive treatment modality
Early stent thrombosis after superficial femoral artery stenting successfully treated with transcatheter rheolytic thrombectomy in a patient with reduced aspirin responsiveness
No full textAbstractPurposeTo describe a case of early superficial femoral artery (SFA) thrombosis after stenting in an aspirin low-responsive patient successfully treated with percutaneous mechanical thrombectomy.Clinical and interventional summaryEarly SFA stent thrombosis occurred in a 65-year-old man treated with multiple stent implantation for chronic total occlusion of the left SFA. The potential cause for thrombosis was a suboptimal PTA [percutaneous transluminal angioplasty] result characterized by no-flow limiting residual linear dissection left untreated and which was associated with low responsiveness to aspirin. Rapid thrombus removal and flow restoration were obtained with the Angiojet Ultra Thrombectomy System (Medrad, Warrendale, PA, USA).ConclusionsTreatment of SFA stent thrombosis should be undertaken with the understanding of the underlying thrombotic causes and the knowledge of the most appropriate therapeutic options. A percutaneous mechanical strategy with the Angiojet Ultra Thrombectomy System may achieve rapid and complete recanalization even in the presence of huge thrombotic burden.<Learning objective: New devices have been available for huge thrombotic burden management in acute clinical peripheral settings. A few clinical experiences have been described and the case we present shows the safety and efficacy of the rheolytic thrombectomy for femoral stent thrombosis management avoiding bleeding and distal embolization risks.
Successful stent delivery with deep seating of 6 French guiding catheters in difficult coronary anatomy
No full textDespite improvements in coronary stent design, delivery difficulties may still be encountered. Between April 1996 and September 1998, 945 patients underwent coronary stenting in our Institute. New 6 Fr Long Brite Tip (LBT) guiding catheters, allowing deep coronary artery intubation and increased backup support, were used in 25 (2.6%) of these patients presenting complex coronary anatomy and poor stent accessibility, electively in 3 (12%) and after stent delivery failure with multiple (2.1 +/- 1.2) standard guiding catheters in 22 (88%). Deep coronary artery intubation (>/= 20 mm) was successfully performed in 22 (88%) patients and was associated with adequate pressure recording and contrast opacification without blood flow compromise. Ten (22.7%) Palmaz-Schatz stents and 34 (77.3%) second-generation stents of various lengths were successfully delivered to different coronary vessels (RCA = 15, LAD = 9, LCx = 1) in all patients in whom deep coronary intubation was obtained. These data demonstrate that deep coronary artery cannulation with LBT catheters is feasible and safe and may markedly increase the rate of stent delivery success in very complex coronary anatomy and when standard guiding catheters have failed
Comparison of nifedipine, propranolol and isosorbide dinitrate on angiographic progression and regression of coronary arterial narrowings in angina pectoris
No full textCalcium antagonists and beta blockers may retard or inhibit atherogenesis. This study investigated whether nifedipine or propranolol influences coronary atherosclerosis in humans. In selected patients with effort angina and proven coronary artery disease, the cineangiographic pattern after 2-year therapy with nifedipine (group 1, 39 patients), propranolol (group 2, 36 patients) or isosorbide dinitrate (group 3, 38 patients) was compared to that before treatment. The disease evolved to a different extent in the 3 groups. Patients with evidence of progression of old narrowings and appearance of new narrowings were significantly fewer in group 1 (31% and 10%) than in group 2 (53% and 34%) and group 3 (47% and 29%). The number of stenoses with evidence of progression was significantly smaller after nifedipine (14), and larger after propranolol (39) compared with group 3 (24). Thus, nifedipine seemed more protective than the other 2 drugs against coronary atherosclerosis. The coronary risk factors were normal in the nifedipine group and remained so with treatment, suggesting that they were dissociated from influences on atherosclerosis. The evolution, as judged by the number of narrowings with progression, appeared significantly (p less than 0.01) worse with propranolol than with isosorbide dinitrate. Propranolol caused unfavorable modifications of serum lipids; there was a 28% increase in total triglycerides and a 25% decrease in high density lipoprotein cholesterol at 12 months in group 2
Large coronary aneurysm complicated by acute myocardial infarction: combined intravascular ultrasound imaging and doppler flow assessment before and after PTFE-covered stent implantation
No full textAlthough most patients with coronary artery aneurysms are asymptomatic, manifestations of myocardial ischemia may occur. However, the role that a coronary aneurysm may play in impairing arterial flow of an otherwise normal coronary circulation is not completely known. A 64-year-old woman with previous anteroseptal myocardial infarction was found to have a large aneurysm of the proximal left anterior descending (LAD) coronary artery without angiographic evidence of atherosclerotic disease. IVUS evaluation revealed an 18 mm long and 12.2 x 10.8 mm wide aneurysm without atherosclerosis, thrombus or calcification. Pulsed wave Doppler showed significant reduction of LAD flow reserve, which normalized after successful obliteration of the aneurysm with polytetrafluoroethylene (PTFE)-covered stent implantation. Severe in-stent graft restenosis was found at 7-month angiographic and intravascular ultrasound follow-up, which was managed successfully with minimally invasive direct coronary bypass surgery. The patient did well, without symptoms over the following year
[The flow-pressure relationship in coronary perfusion in myocardial hypertrophy in hypertension]
No full textFor any given perfusion pressure the difference between coronary autoregulated and maximally vasodilated flow represents the flow reserve. If hypertension and cardiac hypertrophy are present, the line of autoregulated flow becomes higher, and the pressure-flow relationship at maximal vasodilation less steep, due to the raised resistance. In these circumstances, flow reserve reduces and the point at which rest flow equals maximal achievable flow may be shifted to a higher perfusion pressure. Thus, flow would decline even if the perfusion pressure is lowered to normal. We tested this point in a setting of patients having chest pain and normal angiography of the left epicardial branches. Baseline flow (ml/min) from the great cardiac vein (thermodilution) was 142 +/- 13 in 9 normotensives (controls), 144 +/- 15 in 7 hypertensives (Group 1) with normal (114 +/- 11 g) left ventricular mass index and 188 +/- 17 in 8 hypertensives (Group 2) whose left ventricular mass (171 +/- 24 g) exceeded the mean +2 SD of normal. Coronary perfusion pressure was lowered in these patients by 5 mmHg every 5 minutes with a titrated nitroprusside infusion, taking as endpoints a perfusion pressure of 60 mmHg in the controls and of 70 mmHg in hypertensives. At endpoints, flow was similar to baseline in controls and Group 1. In Group 2 flow started to decline and myocardial oxygen extraction to slightly but significantly rise at perfusion pressure of from 90 to 80 mmHg; at the endpoint flow was reduced by 26% of baseline (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS
[Intravenous ultrasonography as a method for imaging the morphoanatomical effects of coronary angioplasty]
No full textDespite the therapeutic success of percutaneous transluminal coronary angioplasty (PTCA), the mechanisms by which PTCA increase vessel luminal size remain uncertain. To better understand the transmural morphologic changes associated with PTCA of stenosed coronary arteries, we studied with a high-frequency intravascular ultrasound catheter 18 coronary artery segments in 18 patients following balloon angioplasty. High-quality cross-sectional images were obtained from 15 coronary sites without complications in all patients. Two distinctive morphologic features following balloon angioplasty were appreciated by intravascular ultrasound imaging. The first pattern, observed in 10 cases (67%), consisted of a stretched plaque without any evidence of dissection. The second pattern, found in 5 cases (33%), demonstrated a dissection of the plaque ranging from a radial tear with separation of the 2 ends of the plaque to an extensive dissection which, in 1 case, encompassed the entire circumference of the artery. Although angiography showed a good post-angioplasty result in all cases, intravascular ultrasound evidenced a large amount of residual atheroma occupying the artery cross-sectional area. In addition, this imaging modality revealed more often than angiography the presence of calcification and dissection. These data demonstrate that PTCA creates different morphologic patterns which are related to the mechanisms of lumen enlargement and that the coronary artery anatomy after dilatation is much more complex than that observed with angiography. This study confirms that intravascular ultrasound is a feasible and safe imaging modality which provides new valuable insight into the mechanisms by which angioplasty improves vessel patency
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