Initial clinical experience with a modified excimer laser for coronary angioplasty

A clinical study was conducted in 32 patients to evaluate the efficacy and safety of a modified excimer laser system for percutaneous transluminal coronary angioplasty. In this system, the laser beam is scanned and transmitted into eight fibre bundles of the catheter device, consisting of 20 50 μm fibres, each. Twenty-eight patients were treated with 1.5 mm laser catheters, four patients with 1.8 mm laser catheters. Mean time of energy delivery was 82±39 s using a mean energy fluence of 49±2 mJ mm⁻². In all 32 patients in whom laser angioplasty was attempted, laser irradiation resulted in a stenosis reduction from 85±10% (mean±s.d.) before to 57±20% after laser treatment. In 16 patients, additional balloon angioplasty had to be performed, either due to an insufficient angiographic result in 11 patients or due to abrupt vessel closure in five patients. In these 16 patients, percent stenosis decreased after balloon angioplasty to 35±14%, corresponding to a luminal diameter of 1.6±0.5 mm. In 10 patients, dissection was observed. In one of these patients, the dissection resulted in a reduction in antegrade flow, necessitating balloon dilatation. One perforation occurred which did not require surgery. There were no deaths, bypass surgery or myocardial infarction. During the time of follow-up, restenosis occurred in 14 patients; in two of these patients bypass surgery was performed and five patients were treated with conventional balloon angioplasty. These results suggest that this form of modified excimer energy delivery provides effective therapy for patients with coronary artery disease. Due to the small catheter sizes, however, one-half of the patients still required additional balloon dilatation. To increase the number of stand-alone laser procedures and to address the issue of restenosis in this patient population appropriately, larger catheter devices will be necessary.     

Percutaneous saphenous vein angioplasty to avoid reoperative bypass surgery

Thirty-seven patients with vein graft stenosis following coronary artery bypass underwent percutaneous transluminal vein graft angioplasty to avoid another operation. Location of the stenoses was at the aortic anastomosis in 3 patients, in the vein body in 12, and at the distal anastomosis in 22. All patients had disabling angina pectoris. Initial success (greater than 20% reduction of stenosis) was achieved in 35 patients. Vein graft angioplasty was performed within a year after bypass in 28 patients. The percent of stenosis and the pressure gradient across the obstruction were reduced from 84 to 24% and from 58 to 15 mm Hg, respectively. Complications of the procedure included emergency coronary artery bypass in 2 patients, myocardial infarction in 2, and ventricular fibrillation in 1. There were no deaths. Of 15 patients with stenosis at the aortic anastomosis or vein body, the dilation was initially successful in 14 but restenosis occurred in 7 within the first year after angioplasty. Only 2 of the remaining 7 were asymptomatic after vein graft angioplasty. However, for patients having vein graft angioplasty of the distal anastomosis, restenosis occurred in only 3, while 12 were asymptomatic at the end of the first year. The average hospital cost of a repeat coronary artery bypass operation was 2.8 times the cost of vein graft angioplasty.     

Coronary artery bypass grafting and replacement of aortic root and ascending aorta; report of a case

An 87-year-old man was referred to our hospital for chest oppression and syncope attack due to aortic stenosis. Further examination revealed severe aortic stenosis (pressure gradient of 107 mmHg, aortic valve area of 0.75 cm2), ascending aortic aneurysm (60 mm in diameter) and triple-vessel disease of coronary arteries. Therefore, a surgical operation was indicated electively. Under cardiopulmonary bypass with normothermia, coronary artery bypass grafting (CABG) was performed. Then the aortic root and the ascending aorta were replaced with a Freestyle valve (27 mm) and a woven Dacron graft (30 mm Hemashield with 1 branch), respectively. Duration of cardiopulmonary bypass and aortic cross-clamp was 267 and 203 minutes, respectively. Postoperative course was uneventful. On the 14th postoperative day, he underwent coronary and graft angiography, which showed all the grafts were patent with good flow. He was successfully discharged on the 19th postoperative day.     

Application of excimer laser angioplasty in acute myocardial infarction

BACKGROUND AND OBJECTIVE: Patients presenting with acute myocardial infarction who fail to respond to standard therapy with thrombolytics or have contraindications for their use oftentimes need revascularization with a mechanical device for removal of an occlusive coronary thrombus and its underlying atherosclerotic plaque. As both thrombi and plaques absorb laser energy in the ultraviolet wavelength (308 nm), we studied the feasibility and safety of excimer laser angioplasty in selective patients with complicated acute myocardial infarction. STUDY DESIGN/MATERIALS AND METHODS: Fifty patients with acute myocardial infarction complicated by continuous chest pain and/or ischemia who had a total of 54 obstructive lesions were treated with percutaneous excimer coronary laser angioplasty (ELCA). A Q-wave myocardial infarction was documented in 56% and a non-Q-wave myocardial infarction in 44%. The baseline left ventricular ejection fraction was reduced at 43 +/- 13% and six patients (12%) presented to the cardiac catheterization laboratory in cardiogenic shock. Twenty-nine patients failed to respond to thrombolytic therapy and 16 had contraindications for thrombolytics and IIb/IIIa receptor antagonists. Following laser debulking, all patients received adjunct balloon dilation and then stents were deployed in 83% of the target lesions. Quantitative coronary arteriography (QCA) was performed at an independent core laboratory. RESULTS: Ninety-eight percent laser success and 100% procedural success were achieved. By QCA the minimal luminal diameter increased from baseline of 0.7 +/- 0.5 to 1.3 +/- 0.5 mm post-lasing and then to 2.0 +/- 0.6 with balloon dilation to a final of 3.0 +/- 0.5 mm. Pre-laser percent stenosis diameter of 77 +/- 17% was reduced to 51 +/- 22% post-laser to 3.0 +/- 17% post-balloon and to a final of 15 +/- 25%. An 83% laser-induced reduction of thrombus burden area was achieved as well as an increase in TIMI flow from baseline of 1.7 +/- 1.1 to 2.8 +/- 0.4 by laser to a 2.9 +/- 0.4 final. There were no deaths, emergency bypass surgery, cerebral vascular accident, neurologic injury, or major perforation. In one case, a laser-induced major dissection was successfully treated by stenting. All 50 patients survived the procedure, improved clinically, and were discharged. CONCLUSION: Application of excimer laser coronary angioplasty is feasible and safe in selected patients with acute myocardial infarction who either fail to respond to thrombolytics or have contraindications to these agents. Intracoronary thrombus at the target lesion can be successfully dissolved with this wavelength laser energy without adverse effect on the procedure results.     

Percutaneous transluminal coronary angioplasty in patients with previous coronary artery bypass grafting]

Percutaneous transluminal coronary angioplasty (PTCA) has been used to treat patients with previous coronary artery bypass grafting (CABG). Seven patients with previous CABG underwent coronary artery or vein graft angioplasty following a recurrence of symptoms. Fifteen lesions were attempted in 7 patients. The primary angiographic success rate was 100%. The primary angiographic success rate was defined as reduction of a stenosis by at least 20% of the vessel diameter, leaving a stenosis of less than 60%. There were no complications following PTCA such as death or myocardial infarction. No patients were referred for urgent surgery. Three patients have undergone another PTCA after 3 months and remain well. All patients at follow-up continue to have improved symptoms. Our experience suggests that the patients with recurrence of coronary artery or bypass stenosis following CABG may be suitable for PTCA.     

Mid-term outcome of surgical coronary ostial plasty: our experience

The conventional coronary artery bypass procedure that uses venous or arterial conduit for isolated critical stenosis of the left main coronary artery (LMCA) restores a less physiological perfusion of the myocardium and uses an appreciable length of bypass material. Coronary ostial plasty has been described as an alternative surgical technique in proximal obstructive coronary artery disease without calcifications. Here we report 23 patients (15 males and 8 females aged 37-78 years; mean age 57 years) who underwent surgical ostial plasty. Ostial reconstruction with fresh pericardial patch was performed in all patients: 15 patients with LMCA stenosis, 6 patients with right coronary (RC) ostial stenosis, and 2 patients with both RC artery and LMCA stenosis. In seven cases, coronary artery bypass grafting was added for contralateral distal stenosis with a total of five arterial conduits and six venous grafts. One patient died; the ostial plasty and grafts were patent at necropsy. Thallium-201 myocardial scintigraphy under stress at 30 days to 6 months after operation demonstrated good myocardial perfusion in 21 of 22 patients. Coronary angiography at follow-up (49 +/- 8 months) demonstrated good surgical ostial plasty results in 21 of 22 patients and good coronary flow in 19 of 22 patients; angiographic study at mid-term follow-up revealed only one failure of the surgical ostial plasty technique associated with venous graft obstruction. In 2 other patients CABG failure due to venous graft obstruction (1 patient) or distal stenotic lesions of the left coronary artery (1 patient) was noted. The overall successful outcome of the surgical ostial plasty was 22 of 23. We believe that surgical angioplasty of the coronary ostia may be used in the presence of proximal noncalcified obstructive lesions as an alternative technique, which offers a more physiological revascularization; it also spares grafting material and allows subsequent percutaneous transluminal angioplasty or coronary artery bypass surgery.     

Preliminary results of intraoperative excimer laser angioplasty: phase 1: an adjunct to coronary artery bypass surgery.

The excimer laser underwent phase I clinical trials at three centers to determine its safety for intraoperative coronary laser angioplasty as an adjunct to coronary artery bypass grafting. A 308-nm Xenon-Chloride, pulsed-wave excimer laser was used to perform angioplasty in 30 patients undergoing coronary artery bypass surgery. Forty vessels (30 patients) were treated, in which the extent of occlusion ranged from 30% to 100%, with complete occlusion in 40% of all vessels. Improvement in vessel luminal caliber was achieved in 33 (79%) vessels, with perforations occurring in 4 (12%) vessels, 2 of which required surgical repair. The lumens of the remaining 8 (19%) vessels were not enlarged, and 2 (5%) of these vessels were perforated. Luminal enlargement was most often achieved in totalled occluded vessels in which 16/17 (94%) were recanalized. No patients died within 30 days postoperatively. Five patients demonstrated biochemical and electrocardiographic evidence of myocardial injury 48 hr postoperatively, and one patient died of cardiac arrest 139 days postoperatively. On the basis of these results, we believe that excimer laser angioplasty can be performed safely to improve coronary luminal patency, even in totally occluded vessels, in an operative setting. The long-term value of this procedure remains to be elucidated.     

Late Patency of the Internal Mammary Artery as a Coronary Bypass Conduit

From January, 1972, through August, 1977, 472 patients had internal mammary artery (IMA) coronary bypass, of which 100 were double-IMA bypasses. We selected those patients having a widely patent IMA one year postoperatively who then had a second catheterization 49 to 105 (mean, 64) months following operation. None of the 93 patients who met these criteria was specifically recalled for this study; they all had follow-up catheterizations for multiple other reasons. All of the 91 left IMA and 22 right IMA bypasses (total, 113) were patent at late catheterization, but 1 right IMA was diffusely narrowed. One left IMA had acute angulation with 50% stenosis proximal to the distal anastomosis, which was unchanged over the follow-up interval. There were 100 patent saphenous vein bypasses at one year and 87 at late catheterization.Late closure of coronary bypass grafts is secondary to progression of coronary disease, atherosclerosis of the bypass conduit, or intimal proliferation. Because we have not encountered the latter two causes of conduit closure, IMA grafts remain our graft of choice for nonemergent operations in patients under 60 years of age having revascularization of the left anterior descending coronary artery system.     

Vascular contractile function following experimental excimer laser angioplasty

The aim of this study was to determine the vasomotor response to in vivo excimer laser irradiation with regard to laser-induced tissue effects. Transfemoral excimer laser angioplasty was performed in the right carotid artery of 11 New Zealand white rabbits. In four additional rabbits (sham group), the procedure was performed without the application of laser energy. Angiography documented vessel dissection in five laser-treated animals. Perforation occurred in one animal. Rings of the treated artery and controls of the contralateral artery were investigated in a contraction chamber. The passive stress-strain relation (PSS) and the maximum contraction force (MCF) after stimulation with noradrenaline, serotonin and potassium chloride were determined. The treated vessels had a higher PSS than the control (p=0.05). The MCF was lower in the treated vessels (p<0.05). The contraction force of the sham-operated vessels was higher, although statistically not significant, compared to the laser-irradiated segments. In a subset analysis, performed to compare vessels with moderate and severe trauma, MCF was significantly reduced in vessels with severe laser-induced injury. Experimental in vivo excimer laser angioplasty in this model resulted in heterogeneous structural changes, including dissections and perforation. Post-mortem assessment of vasomotor response showed no significant difference between laser-treated and sham-operated animals. However, the contractile function of the target vessel seems to be reduced following extensive laser-induced vessel injury.     

A comparison of coronary artery bypass grafting and percutaneous transluminal coronary angioplasty in patients on hemodialysis

The hospital records of 22 patients on hemodialysis undergoing coronary artery bypass grafting, and 19 others undergoing percutaneous transluminal coronary angioplasty were reviewed to compare the outcomes of these procedures in this population. Evidence of previous myocardial infarction or triple vessel or left main coronary artery disease was more common in patients undergoing coronary artery bypass graft than those undergoing percutaneous transluminal coronary angioplasty. Perioperative mortality and complication rates following coronary artery bypass graft (4.5% and 41%, respectively) were similar to those following percutaneous transluminal coronary angioplasty (5.3% and 42%). Cardiac event-free rates at 18 months by life-table analysis following coronary artery bypass graft and percutaneous transluminal coronary angioplasty were 87±16% and 40±14%, respectively. Survival at 18 months were 67±17% following coronary artery bypass graft and 69±14% following percutaneous transluminal coronary angioplasty. Cardiac events were observed to occur in three patients undergoing coronary artery bypass graft at a median of 10 months, and in nine patients following percutaneous transluminal coronary angioplasty at a median of 6 months. One patient required percutaneous transluminal coronary angioplasty after the initial coronary artery bypass graft. Seven patients required repeat percutaneous transluminal coronary angioplasty, and two patients underwent coronary artery bypass graft after initial percutaneous transluminal coronary angioplasty. Although these conclusions are limited by the retrospective nature of the study, it is concluded that coronary artery bypass graft can be performed with morbidity and mortality equivalent to percutaneous transluminal coronary angioplasty, and provides better cardiac event-free rates than percutaneous transluminal coronary angioplasty in patients on hemodialysis. Percutaneous transluminal angioplasty does not appear to be justified in this population because of its unacceptably high restenosis and cardiac event rates.     

Peripheral excimer laser-assisted angioplasty. Preliminary clinical experience.

A non-thermal Xenon-Chloride excimer laser was used for peripheral arterial recanalization in eight patients with obliterating atherosclerosis of the superficial femoral artery. All patients had a total occlusion with severe claudication or pain at rest. There were three complications, which all led to thrombosis of the irradiated artery. In one, the puncture site in the artery had to be closed operatively. All vessels were followed up radiographically three months after the procedure. In seven patients the vessel was patent. Several investigators have warranted caution in using thermal lasers (continuous wave Nd:YAG or argon) for angioplasty. The non-thermal excimer laser is a viable alternative--although not without problems. Initial experiences with the new device are described.     

Fate of the graft and native vessel following endarterectomy of the left anterior descending coronary artery.

In 16 patients who underwent endarterectomy of the left anterior descending (LAD) coronary artery combined with saphenous vein bypass grafting between Aug. 1, 1976 and July 31, 1978, the results of preoperative and postoperative angiography were comparable. Most patients had obstruction or severe stenosis of the proximal LAD coronary artery together with a poor runoff as demonstrated angiographically. Eighteen vein grafts were placed in the LAD artery and 15 (83%) were satisfactorily patent. Six of 18 grafted arterial segments became occluded distal to the site of graft insertion, but in most cases there was sufficient proximal runoff to maintain graft patency. In this study intraoperative measurements of graft flow were predictive of graft or distal vessel patency, or both. Careful postoperative assessment of the results of this technique seems warranted.     

Excimer Laser Assisted Angioplasty for Critical Limb Ischemia: Results of the LACI Belgium Study

BACKGROUND: The purpose of this study was to assess the safety and efficacy of translating into national practice methodology for infrainguinal excimer laser-assisted angioplasty, for the treatment of critical limb ischemia in poor surgical bypass candidates. METHODS: A prospective five centre Belgian registry enrolled 48 patients, who presented with 51 chronic critically ischemic limbs (Rutherford category 4, 5 or 6) and were poor candidates for bypass surgery. Treatment included crossing the occlusion or stenosis by conventional guidewire followed by excimer laser angioplasty with, or without, adjunctive balloon angioplasty or stenting. A step-by-step technique was used in cases where the guidewire could not pass the occluded site. The primary endpoint was limb salvage, at 6 months, of the treated limb. RESULTS: Initial treatment was successful in all 51 limbs. By 6 months there had been six deaths, six minor and four major amputations and further intervention was required in four patients. Among survivors, limb salvage rate at 6 month was 38/42 (90.5%), with freedom from critical limb ischemia in 86%. CONCLUSIONS: This Belgian study of excimer laser assisted angioplasty, in high-risk patients who were poor candidates for surgical re-vascularisation, had a low incidence of surgical re-interventions and limb salvage rate in excess of 90%.     

Recanalization of failed autogenous conduit utilizing laser revascularization

The traditional approach for the treatment of restenosis of autogenous vein bypass has been revision of bypass with vein patch angioplasty, interposition jump graft, or thrombectomy procedures for those patients with extensive occlusive disease and limb-threatening ischemia. Endovascular intervention traditionally involves angioplasty of the graft; however, vessels with diffuse disease or extensive longitudinal lesions are generally difficult to revascularize utilizing this technique. Surgical revision of a threatened autogenous vein graft may carry a morbidity rate as high as 13.6%. We present a series of cases in which excimer laser atherectomy (LA) was used to recanalize an occluded autogenous saphenous vein bypass. Of the occluded vein bypasses failed angioplasty and were successfully atherectomized with LA measuring lengths of 35 and 30 cm, respectively. The infrainguinal has a 6-month follow-up, while the infragencular has a follow-up of 1 year, with resolution of presenting symptoms.     

Can an early peri-anastomotic LITA stenosis be reversible?

Peri-anastomotic graft stenosis is a possible complication of coronary artery bypass graft operations. Early failure of myocardial revascularization may result from graft stenosis with inherent difficulties in perioperative diagnosis and subsequent management. We report the case of a 58-year-old man who experienced early preanastomotic left internal thoracic artery bypass stenosis that progressively resolved during a 2-year period without reoperation or interventional angioplasty. Although the mechanisms underlying graft stenosis remain unclear, this case emphasizes the role of repeated coronary angiography in the choice of treatment.     

Hybrid revascularization feasibility in minimally invasive direct coronary artery bypass grafting combined with percutaneous transluminal coronary angioplasty in patients with acute coronary syndrome and multivessel disease

OBJECTIVES: We reviewed early and midterm outcome of 11 multivessel-disease acute coronary syndrome patients treated by hybrid revascularization, i.e., initial coronary angioplasty followed by minimally invasive direct coronary artery bypass grafting. We evaluated procedural efficacy and applicability. METHODS: Beginning in August 1997, hybrid revascularization was conducted in 11 multivessel-disease acute coronary syndrome patients--9 men and 2 women with a mean age of 70.3 +/- 9.3 years. Occlusion or stenosis of the target coronary artery was treated by interventional cardiologic techniques and minimally invasive direct coronary artery bypass grafting, and the early and midterm outcome evaluated. Coronary angiography was conducted in all cases at 2 weeks, 6 months, 1 and 3 years postoperatively to evaluate anastomosis and restenosis in treated coronary vessels. RESULTS: Initial intervention succeeded in patients with minimal residual stenosis. Subsequent minimally invasive direct coronary artery bypass grafting involved no complications. Coronary angiography early postoperatively, 6 months, 1 and 3 years later showed grafts patent without stenosis. Percutaneous transluminal coronary angioplasty was reconducted on restenotic lesions in 3 patients, 1 of whom required 3 procedures. CONCLUSIONS: Hybrid revascularization appears safe and effective in coronary revascularization, at least over the short term. Several patients underwent angioplasty for restenosis within 3 years after initial procedure. Overall acceptance of this hybrid method depends on long-term functional success of the 2 procedures. Its major limitation is restenosis of angioplasty sites and the need for repeat procedures.     

A difficult case of antiphospholipid syndrome with repeated restenosis of coronary artery and grafts

A 65-year-old man complained of exertional angina. Coronary angiography revealed 99% stenosis in the left anterior descending artery (LAD). He underwent percutaneous transluminal coronary angioplasty (PTCA) and stenting. Repeat angiography demonstrated restenosis of the previous PTCA and stenting site. He underwent coronary artery bypass grafting (CABG) with placement of the left internal thoracic artery (LITA) to LAD. Chest discomfort and V1-V3 ST elevation appeared on the first post operative day. Coronary angiography revealed occlusion of the LITA graft. He underwent re-operation. Because the radial artery was severely sclerotic, the great saphenous vein was used for the graft. Two weeks later, he began to show edema in the left lower extremity. Echoangiogram showed occlusion of the left deep vein with thrombus. He tested positive for anticardiolipin IgG and IgM antibodies. Eighteen months after re-operation, he had recurrent chest discomfort on exertion. Coronary angiography revealed 90% stenosis of the anastomosis (SVG-LAD). A second re-operation was performed. We used the right internal thoracic artery (RITA) for the graft. The postoperative angiography showed patent graft. The patient has been doing well without any complications.     

Angioplasty with autologous pericardium for bilateral coronary ostial stenosis in Takayasu disease

Coronary ostial stenosis is usually treated by conventional coronary artery bypass graft surgery. Although patch angioplasty is a widely accepted alternative surgical treatment, it has been reported sporadically. We encountered bilateral ostial stenosis with Takayasu disease. This report describes successful patch angioplasty using glutaraldehyde-treated autologous pericardium of bilateral coronary ostial stenosis owing to Takayasu disease.     

Excimer laser debulking for percutaneous coronary intervention in left main coronary artery disease

Excimer laser has been successfully applied to complex atherosclerotic plaques in acute coronary syndromes; however, its role in debulking in left main coronary artery disease has not been fully explored. Details of a series of 20 patients who underwent excimer laser revascularization of a spectrum of left main coronary artery lesions are presented. Twenty symptomatic patients who received excimer laser debulking were examined for procedural outcome and follow up results. The left main coronary artery was characterized as protected, semi-protected, poorly protected, or unprotected, depending on the presence or absence of patent bypass grafts to the left anterior descending (LAD) and circumflex (CX) arteries. A fully protected left main coronary artery (LMCA) was present in only 20% of the patients. The target lesions included 11(55%) distal LMCA stenoses, six (30%) ostial stenoses, and one (5%) mid-portion lesions. Two (10%) patients had in-stent re-stenosis of the entire length of the LMCA. Small (0.7 mm–1.4 mm) excimer laser catheters were mostly used. A relatively high number of laser energy pulses (1,334 ± 643) were required to achieve adequate debulking. Successful LMCA intervention was performed in 19 (95%) patients, while in-hospital complications occurred in only one (5%) patient. Subacute/late stent thrombosis developed 3 months after the procedure in one patient, and two patients died from non-cardiac causes during follow-up. Lesions in LMCAs can be revascularized in selected patients by laser debulking and adjunct stenting. Inadequate protection by bypass grafts and decreased left ventricular function do not contradict utilization of excimer laser. Small laser catheters and high energy levels are required during laser debulking of stenoses of left main coronary arteries.     

Lateral femoral circumflex artery for coronary artery bypass surgery in a patient receiving hemodialysis: report of a case

A 59-year-old man receiving hemodialysis had a 2-vessel coronary disease. We performed double coronary artery bypass grafting with the left internal thoracic artery to the left anterior descending artery, and the composite graft of right internal thoracic artery and lateral femoral circumflex artery to the right coronary artery. Postoperative coronary angiogram showed that the LFCA bypass graft was widely patent and supplied sufficient blood to the anastomosed vessel. There was no stenosis at the anastomotic site. He had no postoperative complication. Long-term follow-up and more cases is necessary to establish the usefulness of LFCA as an arterial free graft for coronary revascularization in patients receiving hemodialysis.