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On Topaz

Publications and source records attributed to On Topaz.

At least 19 recordsLinked to original sources
PubMed2005

Prevention of distal embolization and no-reflow in patients with acute myocardial infarction and total occlusion in the infarct-related vessel: a subgroup analysis of the cohort of acute revascularization in myocardial infarction with excimer laser-CARMEL multicenter study.

To overcome the adverse complications of percutaneous coronary interventions in thrombus laden lesions (i.e., distal embolization, platelet activation, no-reflow phenomenon), mechanical removal of the thrombus or distal embolization protection devices are frequently required. Pulsed-wave ultraviolet excimer laser light at 308 nm can vaporize thrombus, suppress platelet aggregation, and, unlike other thrombectomy devices, ablate the underlying plaque. The following multicenter registry was instituted to evaluate the safety and efficacy of laser ablation in patients presenting with acute myocardial infarction (AMI) complicated by persistent thrombotic occlusions. Patients with AMI and complete thrombotic occlusion of the infarct-related vessel were included in eight participating centers. Patients with further compromising conditions (i.e., cardiogenic shock, thrombolysis failures) were also included. Primary endpoint was procedural respective laser success; secondary combined endpoints were TIMI flow and % stenosis by quantitative coronary analysis and visual assessment at 1-month follow-up. Eighty-four percent of all patients enrolled (n = 56) had a very large thrombus burden (TIMI thrombus scale > or = 3), and 49% were compromised by complex clinical presentation, i.e., cardiogenic shock (21%), degenerated saphenous vein grafts (26%), or thrombolysis failures (5%). Laser success was achieved in 89%, angiographic success in 93%, and the overall procedural success rate was 86%. The angiographic prelaser total occlusion was reduced angiographically to 58% +/- 25% after laser treatment and to 4% +/- 13% final residual stenosis after adjunctive balloon angioplasty and/or stent placement. TIMI flow increased significantly from grade 0 to 2.7 +/- 0.5 following laser ablation (P < 0.001) and 3.0 +/- 0.2 upon completion of the angioplasty procedure (P > 0.001 vs. baseline). Distal embolizations occurred in 4%, no-reflow was observed in 2%, and perforations in 0.6% of cases. Laser-associated major dissections occurred in 4% of cases, and total MACE was 13%. The safety and efficacy of excimer laser for thrombus dissolution in a cohort of high-risk patients presenting with AMI and total thrombotic occlusion in the infarct-related vessel are encouraging and should lead to further investigation.

Aged↗
PubMed2004

Excimer laser angioplasty in acute myocardial infarction (the CARMEL multicenter trial).

Patients with acute myocardial infarction (AMI) with thrombus-laden lesions constitute a revascularization challenge. Thrombus and atherosclerotic plaque absorb laser energy; thus, we studied the safety and efficacy of excimer laser in AMI. In a multicenter trial, 151 patients with AMI underwent excimer laser angioplasty. Baseline left ventricular ejection fraction was 44 +/- 13%, and 13% of patients were in cardiogenic shock. A saphenous vein graft was the target vessel in 21%. Quantitative coronary angiography and statistical analysis were performed by independent core laboratories. A 95% device success, 97% angiographic success, and 91% overall procedural success rate were recorded. Maximal laser gain was achieved in lesions with extensive thrombus burden (p <0.03 vs small burden). Thrombolysis In Myocardial Infarction (TIMI) trial flow increased significantly by laser: 1.2 +/- 1.1 to 2.8 +/- 0.5 (p <0.001), reaching a final 3.0 +/- 0.2 (p <0.001 vs baseline). Minimal luminal diameter increased by laser from 0.5 +/- 0.5 to 1.6 +/- 0.5 mm (mean +/- SD, p <0.001), followed by 2.7 +/- 0.6 mm after stenting (p <0.001 vs baseline and vs after laser). Laser decreased target stenosis from 83 +/- 17% to 52 +/- 15% (mean +/- SD, p <0.001 vs baseline), followed by 20 +/- 16% after stenting (p <0.001 vs baseline and vs after laser). Six patients (4%) died, each presented with cardiogenic shock. Complications included perforation (0.6%), dissection (5% major, 3% minor), acute closure (0.6%), distal embolization (2%), and bleeding (3%). In a multivariant regression model, absence of cardiogenic shock was a significant factor affecting procedural success. Thus, in the setting of AMI, gaining maximal thrombus dissolution in lesions with extensive thrombus burden, combined with a considerable increase in minimal luminal diameter and restoration of anterograde TIMI flow, support successful debulking by excimer laser. The presence of thrombus does not adversely affect procedural success; however, cardiogenic shock remains a predictor of major adverse events during hospitalization.

Angioplasty, Laser↗
PubMed2004

Excimer laser ablation for valvular angioplasty in pulmonary atresia and intact ventricular septum.

BACKGROUND AND OBJECTIVES: The prognosis for infants with pulmonary atresia and intact ventricular septum (PA/IVS) is poor and they present a major management challenge. Mechanical penetration of the atretic pulmonary valve is an applicable option for decompression of the right ventricle and optimization of left ventricular function. The utilization of laser energy for debulking and vaporization of the atretic valve tissue is a relevant approach due to the potential for controlled, precise mode of energy distribution. STUDY DESIGN/PATIENTS AND METHODS: A 4-month-old female with PA/IVS whose failure to thrive was accompanied by critical hemodynamic abnormalities received successful percutaneous pulmonary valve plate ablation by a 0.9 mm pulsed-wave ultraviolet excimer laser catheter (308 nm wavelength, fluence 50 mJ/mm(2); 30 Hz). A "step-by-step" lasing technique was applied whereby the tip of the emitting laser catheter is advanced ahead of a guide wire that serves mainly as support for positioning of that catheter. RESULTS: Adequate penetration of the atretic tissue enabled introduction of balloon dilations resulting in patency of the atretic valve, decompression of the right ventricle, improved right and left ventricular hemodynamics, and oxygenation. To further investigate the effect of excimer laser energy on atretic valvular tissue this laser was applied in a specimen of heart from an infant who died because of PA/IVS. Histopathologic examination of the irradiated tissue revealed no laser-induced injury to the pulmonary valve. CONCLUSIONS: Thus, laser ablation and penetration of an atretic pulmonary valve is feasible and safe. The penetration of the atretic valve with the laser catheter enables subsequent introduction of various sizes balloon dilations. The application of available laser sources for treatment of congenital heart diseases is reviewed.

Female↗
PubMed2004

Excimer laser revascularization of saphenous vein grafts in acute myocardial infarction.

Patients who develop acute myocardial infarction due to occlusion in a saphenous vein graft (SVG) constitute a revascularization challenge. Excimer laser angioplasty may have a potential advantage in the treatment of SVGs, since its 308 nanometer wavelength is avidly absorbed by both atherosclerotic plaque and thrombus. The data presented herein support the notion that excimer laser angioplasty is a technology that has a potential role in achieving adequate revascularization outcomes in this selected, high-risk patient population.

Aged↗
PubMed2003

Comparison of effectiveness of excimer laser angioplasty in patients with acute coronary syndromes in those with versus those without normal left ventricular function.

Depressed left ventricular (LV) ejection fraction (EF) adversely affects procedural outcome during percutaneous coronary revascularization. This study examined the acute results, effectiveness, and safety of excimer laser coronary angioplasty (ELCA) in patients with acute coronary ischemic syndromes whose LVEF was depressed (<40%) versus those with preserved LVEF. One hundred patients with acute coronary syndromes (51 with unstable angina and 49 with acute myocardial infarction) underwent ELCA. Twenty-five patients (group 1) (29 lesions; 72% thrombotic) had decreased LVEF (mean 28 +/- 6%) and 75 patients (group 2) (81 lesions; 60% thrombotic) had preserved LVEF (mean 53 +/- 8%). Group 1 had a higher incidence of 3-vessel disease, Q-wave acute myocardial infarction, cardiogenic shock, diabetes, and hypertension. High laser success (87% group 1 vs 93% group 2, p = NS) and procedural success (93% group 1 vs 98% group 2, p = NS) were achieved in both groups. Minimal luminal diameter in group 1 increased from 0.7 +/- 0.5 to 1.4 +/- 0.5 mm after the laser procedure and finally to 3.0 +/- 0.4 mm; in group 2, minimal luminal diameter increased from 0.7 +/- 0.4 to 1.3 +/- 0.5 mm after the procedure to a final of 3.0 +/- 0.5 mm. The laser energy vaporized 75% of thrombus burden from the target lesion in group 1 versus 79% in group 2 (p = NS). Thrombolysis In Myocardial Infarction flow in group 1 increased from 1.4 +/- 1.2 to 2.7 +/- 0.7 by laser and finally to 2.9 +/- 0.3, and in group 2 from 2.0 +/- 1.0 to 2.8 +/- 0.6 after the laser procedure to a final of 2.9 +/- 0.4. There were no deaths, emergency bypass surgeries, strokes, or acute vessel closures in either group. Thus, ELCA is a safe and feasible revascularization modality for patients with acute coronary syndromes whose LVEF is depressed. The laser energy vaporizes a large thrombus burden from the treated plaque. Angiographic intracoronary thrombus does not adversely affect device and procedural success in these select patients.

Acute Disease↗
PubMed2003

The implications of common brachiocephalic trunk on associated congenital cardiovascular defects and their management.

A common brachiocephalic trunk is an anatomic variant in which both common carotid arteries and the right subclavian artery arise from the aortic arch via a single trunk. The impact of this condition on associated congenital cardiac malformations is presently unknown. Out of a total of 1480 cardiac catheterizations performed in children over a period of 10 years, we discovered 48 patients (3.2%) to have a common brachiocephalic trunk, of whom 98% had associated congenital cardiac malformations. A spectrum of associated lesions was identified, including left-to-right shunts in 19 patients, right-sided anomalies in 18 patients, left-sided obstructive lesions in 12 patients, and coronary arterial abnormalities in 10 patients, eight of whom had other cardiac defects. Genetic syndromes were present in one-fifth of the cases. When found with left-sided malformations, the common trunk was associated with persistent hypoplasia of the aortic arch, likely related to diminished flow through the arch during development. In each of four patients in whom the brachiocephalic trunk had been used during construction of a palliative shunt, we observed inadequate growth and deformation of the pulmonary arteries. Thus, angiographic identification of a common brachiocephalic trunk may be a marker for the presence of accompanying congenital cardiac defects and coronary arterial abnormalities. Understanding the pathophysiologic effects of the common trunk is important when planning the palliative or corrective procedures, and when assessing the potential benefit of the surgical repair over the long term.

Brachiocephalic Trunk↗
PubMed2002

Laser-facilitated thrombectomy: a new therapeutic option for treatment of thrombus-laden coronary lesions.

To overcome the adverse complications of balloon angioplasty in thrombus burden lesions (i.e., distal embolization, platelet activation, no-reflow phenomenon with persistent myocardial hypoxemia), mechanical removal of the thrombus or distal embolization protection devices is required. Pulsed ultraviolet excimer laser light at 308 nm can vaporize thrombus and suppress platelet aggregation. Clinical experience has already shown its efficacy in acute ischemic-thrombotic acute coronary syndromes. Unlike other thrombectomy devices, a 308 nm excimer laser can ablate thrombi as well as the underlying plaque, speed up thrombus clearing, and enhance thrombolytic and GP IIb/IIIa activity. It can also be employed in patients with contraindications for systemic thrombolytic agents or GP IIb/IIIa antagonists. Our report covers clinical data and technical aspects concerning three patients with acute myocardial infarction who presented with a large thrombus burden. After successful laser-transmitted vaporization of the thrombus mass in these patients, the remaining thrombus burden was evacuated, and normal antegrade coronary flow was successfully restored. This approach can be useful for selective patients with acute coronary syndromes.

Aged↗