Evaluation of the long-term functional outcome assessed by myocardial perfusion scintigraphy following excimer laser angioplasty compared to balloon angioplasty in longer coronary lesions.

OBJECTIVES: Evaluation of the long-term functional outcome assessed by exercise myocardial perfusion imaging following excimer laser angioplasty compared to balloon angioplasty in coronary lesions > 10 mm in length. BACKGROUND: Previous randomized studies evaluating the effect of coronary interventions mainly focused on the long-term clinical and angiographic outcome. The functional outcome, assessed by myocardial perfusion scintigraphy, has not been evaluated in a randomized setting. METHODS: A total of 308 patients with stable angina and a longer coronary lesion (> 10 mm) were randomized to excimer laser angioplasty or balloon angioplasty. A 99mTechnetium-2-methoxy isobutyl isonitrile (MIBI) single-photon emission computed tomography (SPECT) study was performed in 139 patients before the initial angioplasty procedure and at 6 months follow-up (73 patients in the laser group versus 66 patients in the balloon group, respectively). Exercise tolerance at follow-up was compared to baseline values by means of exercise duration and double product at peak exercise. Myocardial perfusion of the randomized vascular bed was assessed semi-quantitatively on the MIBI SPECT images. The reversible defects were graded as mild, moderate or severe. Myocardial perfusion at follow-up was expressed as a percentage reduction in incidence and grading of the reversible defects compared to baseline values. RESULTS: Forty-four (61%) patients assigned to laser angioplasty were asymptomatic at 6 months follow-up compared to 34 (52%) patients assigned to balloon angioplasty (p = NS). Improvement in exercise duration and double product were 0.7 +/- 2.1 min and 4.3 +/- 6.2 min/mmHg/l,000, respectively, in the laser group, versus 0.3 +/- 2.5 min and 3.1 +/- 5.5 min/mmHg/1,000, respectively, in the balloon group (both p = NS). The percentage reduction of reversible defects was 23% in patients assigned to laser angioplasty vs. 29% in patients assigned to balloon angioplasty (Relative risk [RR]: 0.79, 95% confidence interval [CI]: 0.40-1.57; p = 0.50). The mild, moderate and severe reversible defects improved in 44.4, 63.6 and 66.6%, respectively, in the laser angioplasty group vs. 66.6, 53.8 and 90%, respectively, in the balloon angioplasty group. None of the comparisons were significantly different. CONCLUSION: Excimer laser angioplasty compared to balloon angioplasty in coronary lesions > 10 mm in length yields a similar long-term functional outcome assessed by anginal status, exercise tolerance and myocardial perfusion.

An analogue laser optical disc in comparison with cinefilm for visual analysis of coronary narrowings before and after coronary angioplasty.

This study evaluated an analogue laser optical disc (MVP) as an alternative for cinefilm angiography in the visual analysis of coronary angiograms. Visual analysis was performed independently by 5 observers using cinefilm and MVP before and after PTCA (194 coronary lesions in 88 patients) and the outcomes were compared with QCA. The mean percentage diameter stenosis on cinefilm and MVP yielded similar results compared to QCA. Regression analysis showed a good correlation between the mean cinefilm and MVP values per diameter stenosis (p < 0.001). Bland-Altman plots confirmed these findings. Qualitative analysis for detection of coronary dissections after PTCA showed an incidence of 31.3% (cinefilm) and 21.8% (MVP) (p < 0.05). The results of this study indicate that the visual analysis of the coronary angiograms using the analogue laser optical disc (MVP) yields similar results compared to the cinefilm concerning coronary lesion severity, although there is an underestimation of coronary dissections.

Clinical events following excimer laser angioplasty or balloon angioplasty for complex coronary lesions: subanalysis of a randomised trial.

OBJECTIVES: To compare clinical outcome in patients with complex coronary lesions treated with either excimer laser coronary angioplasty (ELCA) or balloon angioplasty. PATIENTS AND DESIGN: 308 patients with stable angina and a coronary lesion of more than 10 mm in length were randomised to ELCA (151 patients, 158 lesions) or balloon angioplasty (157 patients, 167 lesions). The primary clinical end points were death, myocardial infarction, coronary bypass surgery, or repeated coronary angioplasty of the randomised segment during six months of follow up. Subanalysis was performed to identify a subgroup of patients with a beneficial clinical outcome following ELCA or balloon angioplasty. SETTING: Two university hospitals and one general hospital. RESULTS: There were no deaths. Myocardial infarction, coronary bypass surgery, and repeated angioplasty occurred in 4.6, 10.6, and 21.2%, respectively, of patients treated with ELCA compared with 5.7, 10.8, and 18.5%, respectively, of those treated with balloon angioplasty. ELCA did not yield a favourable clinical outcome in subgroups of patients with long (more than 20 mm) coronary lesions, calcified lesions, small diseased vessels (< or = 2.5 mm reference diameter), or total coronary occlusions. There was a worse clinical outcome in patients with tandem lesions treated with ELCA compared with balloon angioplasty (9/18 v 3/26 lesions; p = 0.01); while a trend towards an unfavourable clinical outcome was found in patients with vessels with a reference diameter of more than 2.5 mm (23/66 v 13/63 lesions, p = 0.07) and left circumflex coronary lesions (12/41 v 6/42 lesions, p = 0.08). CONCLUSIONS: The findings indicate a worse clinical outcome in patients with lesions of more than 10 mm treated with ELCA compared with balloon angioplasty who have tandem coronary lesions and in those with vessels with a reference diameter of more than 2.5 mm and left circumflex coronary lesions.

Early ambulation after coronary angioplasty and stenting with six French guiding catheters and low-dose heparin.

The safety and feasibility of early ambulation was evaluated prospectively in 907 patients undergoing elective coronary angioplasty and stenting with the use of 6Fr guiding catheters, low-dose heparin (5,000 IU), and immediate postprocedural sheath removal by comparing ambulation after 4 hours with immobilization for at least 12 hours. Because no excess in puncture site complications (2.3% vs 2.2%) could be demonstrated after 4-hour ambulation, it is concluded that early ambulation after 6Fr guiding catheter angioplasty by the femoral route with low-dose heparin is feasible, safe, and may facilitate a shorter hospital stay.

Pharmacological modulation of the human collateral vascular resistance in acute and chronic coronary occlusion assessed by intracoronary blood flow velocity analysis in an angioplasty model.

BACKGROUND: The pharmacological responsiveness of the coronary collateral circulation in humans has been studied only by indirect means. METHODS AND RESULTS: Patients with one-vessel disease and recruitable (n = 14) or spontaneously visible (n = 24) collateral vessels were studied during coronary angioplasty. Collateral flow in the recipient coronary artery was determined with a 0.014-in Doppler guide wire during balloon coronary occlusion and expressed as the diastolic blood flow velocity integral (dVi). Collateral blood flow velocity, mean aortic pressure (Pao), and coronary wedge pressure (Pw) were used to calculate the collateral vascular resistance index: Rcoll = (Pao-Pw)/ dVi (mm Hg/cm) and the peripheral vascular resistance index of the recipient coronary artery: R4 = Pw/dVi (mm Hg/cm). Adenosine (12 to 18 micrograms) and nitroglycerin (0.2 mg) were injected as a bolus in the donor coronary artery during subsequent balloon inflations to assess their effect on these hemodynamic variables. The administration of adenosine or nitroglycerin in patients with recruitable collateral vessels did not induce a change in dVi and Pw/Pao ratio. In patients with spontaneously visible collateral vessels, dVi increased from 8.0 +/- 4.5 to 10.8 +/- 8.0 cm (P = .01) after adenosine and from 7.4 +/- 4.5 to 10.3 +/- 6.9 cm (P = .003) after nitroglycerin. The Pw/Pao ratio remained unchanged after adenosine and nitroglycerin. Rcoll decreased from 10.3 +/- 9.5 to 8.6 +/- 8.5 mm Hg/cm (P = .01) after adenosine and from 11.6 +/- 10.4 to 8.3 +/- 8.9 mm Hg/cm (P < .001) after nitroglycerin. R4 decreased from 7.7 +/- 5.5 to 5.9 +/- 5.1 mm Hg/cm (P < .001) after adenosine and from 8.4 +/- 6.6 to 7.1 +/- 7.2 mm Hg/cm (P = .01) after nitroglycerin. CONCLUSIONS: Coronary collateral blood flow can be increased with adenosine and nitroglycerin in patients with one-vessel disease and spontaneously visible collateral vessels, which is in contrast to patients with recruitable collateral vessels. This effect is the result of a reduction in the collateral vascular resistance and peripheral vascular resistance of the recipient coronary artery.

Comparison of collateral vascular responses in the donor and recipient coronary artery during transient coronary occlusion assessed by intracoronary blood flow velocity analysis in patients.

OBJECTIVES: This study was designed to evaluate the hemodynamic variables of the collateral circulation during acute coronary occlusion. BACKGROUND: There is limited information on the physiology of the collateral circulation in coronary artery disease. METHODS: Angiography of the contralateral donor artery was performed before and during balloon coronary occlusion in 57 patients with one-vessel disease. Recruitable collateral flow was assessed during coronary occlusion by blood flow analysis of the contralateral donor artery (n = 19) or the ipsilateral recipient artery (n = 15), or both (n = 23), using a Doppler catheter or guide wire. Ischemia was evaluated by the ST segment shift (> or = 0.1 mV) on a 12-lead electrocardiogram at 1 min of coronary occlusion. RESULTS: The presence (n = 39), compared with the absence (n = 18), of recruitable collateral vessels was associated with an increase of blood flow velocity in the donor artery (20 +/- 19% vs. 4.8 +/- 5.9% [mean +/- SD], p = 0.003) and the recipient artery (velocity integral 7.2 +/- 5.5 vs. 2.8 +/- 2.2 cm, p = 0.02) related to a reduced relative collateral vascular resistance (9.2 +/- 10 vs. 20 +/- 11, p = 0.003). Collateral flow in the donor artery yielded a similar predictive value for recruitability of collateral vessels as collateral flow determined in the recipient artery or the coronary wedge/aortic pressure ratio (areas under the receiver operating characteristics curves 0.76 +/- 0.07, 0.78 +/- 0.08, 0.77 +/- 0.07, respectively, p = NS). Collateral flow in the recipient artery was a better predictor for ischemia than collateral flow in the donor artery or angiographic grading of collateral vessels (areas 0.90 +/- 0.05, 0.64 +/- 0.10, 0.73 +/- 0.07, respectively, p < 0.05). CONCLUSIONS: Coronary blood flow velocity analysis of the donor and recipient coronary arteries can characterize the dynamics of the collateral circulation during acute coronary occlusion. The protective effect of recruitable collateral vessels relates to an increase of flow in the donor and recipient coronary arteries due to a reduced collateral vascular resistance. This study underscores the importance of physiologic variables for the evaluation of the function of recruitable collateral vessels.

Safety of low dose heparin in elective coronary angioplasty.

OBJECTIVES: To evaluate the safety of a low dose of heparin in consecutive stable patients undergoing elective percutaneous transluminal coronary angioplasty (PTCA). DESIGN: Open prospective study in a single centre. PATIENTS: 1375 consecutive patients had elective PTCA (1952 lesions: type A 11%, B1 34%, B2 36%, and C 19%). There were no angiographic exclusion criteria. INTERVENTIONS: A bolus of 5000 IU heparin was used as the standard anticoagulation regimen during PTCA. The sheaths were removed immediately after successful completion of the procedure. Prolongation of heparin treatment was left to the operator's discretion. MAIN OUTCOME MEASURES: Procedural success was defined as < 50% residual stenosis without death from any cause, acute myocardial infarction, urgent coronary bypass surgery, or repeat angioplasty within 48 hours for acute recurrent ischaemia; the need for prolonged heparinisation; and the occurrence of puncture site complications. RESULTS: Procedural success without clinical events was achieved in 90% of patients. Mortality was 0.3%; coronary bypass surgery was performed in 1.7% of the procedures. The rate of myocardial infarction was 3.3%; repeat angioplasty within 48 hours was carried out in 0.7% of patients. A total of 89.1% of the patients were treated according to the protocol. Prolonged treatment with heparin was considered necessary in 123 patients (8.9%). Repeat angioplasty for abrupt closure was performed in two patients shortly after sheath removal and in two during prolonged heparinisation. Puncture site complications occurred in 2.1% of patients (low dose heparin 1.9% and prolonged heparinisation 4.9%). CONCLUSION: Elective PTCA can be safely performed using a low dose of heparin, with a negligible risk for subacute closure. Low dose heparin may reduce the incidence of puncture site complications, shorten hospitalisation, and enable out-patient angioplasty.

Does a waiting time for elective coronary angioplasty affect the primary success rate?

OBJECTIVE: To evaluate the effect of the waiting time for elective percutaneous transluminal coronary angioplasty (PTCA) on the primary success rate. SETTING: University hospital in The Netherlands. PATIENTS: A cohort of 817 consecutive patients awaiting elective PTCA. Scheduled PTCA was performed in all 817 patients, involving 1237 coronary lesions. MAIN OUTCOME MEASURES: The relation between procedural success and the duration of the waiting time was evaluated. Major cardiac events, that is, death and myocardial infarction while awaiting PTCA, were documented. Alterations in lesion characteristics during the waiting time were assessed in unsuccessful procedures. RESULTS: Elective PTCA was performed within one to six weeks after acceptance in 388 patients (587 lesions; 47.5%), between six and 12 weeks in 203 patients (308 lesions; 25%), and after more than 12 weeks in 226 patients (342 lesions; 27.5%). The procedural success rates in the defined time intervals were 97%, 99%, and 97% in ACC/AHA type A lesions, 93%, 87% and 90% in type B lesions, and 63%, 55% and 38% in type C lesions respectively; 96% of type C lesions were total coronary occlusions. There was a significant decrease in primary success rate in type C lesions after a waiting time beyond 12 weeks. A reasonable explanation for an unsuccessful angioplasty related to alterations in lesion characteristics during the waiting time was documented in only four of 115 procedures. CONCLUSIONS: The primary success in type A and B lesions is unaffected by the duration of a waiting period for elective PTCA. A waiting time of more than 12 weeks is associated with a lower success rate in patients with total coronary occlusions.

Angioplasty of chronic total coronary occlusions with the use of six French guiding catheters.

The efficacy of 6 French guiding catheters for angioplasty of chronic total coronary occlusions was evaluated in 61 consecutive patients. The duration of the occlusion was determined angiographically, or estimated from an index clinical event. Endpoints were procedural success, defined as recanalization with less than 50% residual stenosis without major complications; and the need to change to larger-sized guiding catheters. Recanalization was attempted in 62 chronic total occlusions; 35 were located in the left anterior descending coronary artery, 18 in the right coronary artery, and 9 in the left circumflex coronary artery. The mean duration of the occlusion was 6.0 +/- 6.6 months; the range was 2-39 months. Lesion morphology included abrupt or diffuse occlusion (55%), a side branch originating at the occlusion (47%), and bridging collaterals (23%). Death, urgent coronary bypass surgery, or myocardial infarction did not occur. Recanalization was successful in 51 of the 62 total occlusions (82%); 49 were completed successfully with a 6 French guiding catheter, and 2 were successful after changing to a larger-sized guiding catheter (which was required for peripheral vessel tortuosity in one patient, and to obtain better back-up support in another). Three other attempts remained unsuccessful after a changing. A total of 12 Palmaz-Schatz stents were implanted in 11 patients for an unsatisfactory result or type C dissection, using the same 6 French guiding catheters. These preliminary findings indicate that 6 French guiding catheters are both effective and safe for angioplasty of chronic total occlusions.

Clinical, angiographic and hemodynamic predictors of recruitable collateral flow assessed during balloon angioplasty coronary occlusion.

OBJECTIVES: We sought to determine the predictive value of factors influencing coronary collateral vascular responses in humans. BACKGROUND: There is limited information on the factors responsible for coronary collateral vascular development, despite the protective effect of collateral vessels in ischemic syndromes. METHODS: Angiography of the contralateral artery was performed during balloon coronary occlusion in 105 patients with single-vessel disease (left anterior descending coronary artery in 69 patients, left circumflex coronary artery in 4 patients, right coronary artery in 32 patients) and normal left ventricular function. Collateral vessels were graded according to the classification of Rentrop. The relative collateral vascular resistance was calculated in a subgroup of 34 patients by means of aortic pressure, coronary wedge pressure and collateral flow, defined as the transient increase of coronary blood flow velocity of the contralateral artery during balloon coronary occlusion. Ischemia during coronary occlusion was evaluated by the ST segment shift (mV) in a 12-lead electrocardiogram (ECG). RESULTS: A multivariate logistic analysis of clinical and angiographic variables revealed duration of angina (> or = 3 months, p < 0.0001), lesion severity (> or = 75% diameter stenosis, p < 0.0001) and proximal lesion location (p = 0.02) as independent factors positively associated with recruitability of collateral vessels, whereas the use of nitrates exerted an independent negative effect (p = 0.01). The regression equation yielded an overall predictive accuracy of 80%. The presence of recruitable collateral vessels during coronary occlusion resulted in a higher coronary wedge/aortic pressure ratio (mean [+/- SD] 0.35 +/- 0.13 vs. 0.27 +/- 0.12, p < 0.005), a lower relative collateral vascular resistance (6.7 +/- 7.4 vs. 21.3 +/- 10, p < 0.001) and a reduction of ECG signs of ischemia (0.14 +/- 0.19 vs. 0.38 +/- 0.33 mV, p < 0.001). The relative collateral vascular resistance was the best predictor for recruitability of collateral vessels compared with the other variables related to collateral vascular growth (p < 0.05). CONCLUSIONS: Clinical and angiographic variables predict recruitability of collateral vessels with an 80% overall accuracy. These findings are important for risk stratification of patients undergoing interventions for ischemic coronary syndromes.

Short-term (4 hours) observation after elective coronary angioplasty.

In a prospective evaluation of the safety of short-term observation after elective percutaneous transluminal coronary angioplasty (PTCA) in 1,900 consecutive patients, 1 of 1,680 patients triaged to discharge after 4 hours of observation reached the primary end point of acute recurrent ischemia, 7 patients underwent repeat PTCA during 4 hours of observation, and 66 of 187 patients selected for prolonged observation had a complicated course. It is concluded that short-term observation after elective coronary angioplasty is safe, with a negligible risk of vessel closure after this period; triage for prolonged observation can be based appropriately on the immediate procedural result.

Excimer laser angioplasty versus balloon angioplasty in functional and total coronary occlusions.

Registries of excimer laser coronary angioplasty have reported good results in the treatment of complex coronary artery disease, including total or subtotal coronary occlusions. One hundred three patients (103 lesions) with a functional or total coronary occlusion were included in a randomized trial (Amsterdam-Rotterdam [AMRO] trial, total of 308 patients), 49 patients were allocated to laser angioplasty and 54 patients to balloon angioplasty. The primary clinical end points were death, myocardial infarction, coronary bypass surgery, or repeated coronary angioplasty of the randomized segment during a 6-month follow-up period. The primary angiographic end point was the minimal lumen diameter at follow-up in relation to the baseline value (net gain), as determined by an automated contour-detection algorithm. Laser angioplasty was followed by balloon angioplasty in all procedures. The angiographic success rate was 65% in patients treated with excimer laser-assisted balloon angioplasty compared with 61% in patients treated with balloon angioplasty alone. No deaths occurred. There were no significant differences between the laser angioplasty group and the balloon angioplasty group in the incidence of myocardial infarctions (1 patient vs 3, respectively, p = 0.36), coronary bypass surgery (4 patients vs 2, respectively, p = 0.34), repeat angioplasty (10 patients vs 8, respectively, p = 0.46) or primary clinical end point (15 patients vs 12, respectively, p = 0.34). The net gain in minimal lumen diameter and restenosis rate (>50% diameter stenosis at follow-up) were 0.81 +/- 0.74 mm and 66.7%, respectively, in patients treated with laser angioplasty compared with 1.04 +/- 0.68 mm and 48.5%, respectively, in patients treated with balloon angioplasty (p = 0.59 and p = 0.15, respectively). Excimer laser-assisted balloon angioplasty demonstrated no benefit over balloon angioplasty with respect to initial and long-term clinical and angiographic outcome in the treatment of patients with functional or total coronary occlusions of >10 mm in length.

Clinically stable angina pectoris is not necessarily associated with histologically stable atherosclerotic plaques.

OBJECTIVE: To investigate the extent of plaque inflammation in culprit lesions of patients with chronic stable angina. DESIGN: Retrospective study. SETTING: Amsterdam reference centre. SUBJECTS: 89 consecutive patients who underwent directional coronary atherectomy, 58 of whom met the following inclusion criteria: chronic stable angina (Canadian Cardiovascular Society classification 1-3 (group 1, n = 28)); unstable angina (Braunwald class II (group 2, n = 18)); unstable angina (Braunwald class III (group 3, n = 12)). INTERVENTIONS: Directional atherectomy in patients with angina pectoris. MAIN OUTCOME MEASURES: Tissue areas of culprit lesions occupied by inflammatory cells and smooth muscle cells related to clinically defined ischaemic syndrome. RESULTS: Areas (% of total surface area (mean (SEM)) rich in smooth muscle cells were larger in patients with chronic stable angina (group 1, 51.2 (20.9)) than in those with unstable angina (group 2, 42.1 (20.5); group 3, 29.5 (19.4)) (1 v 2 and 2 v 3, NS; 1 v 3, P < 0.004). Macrophage rich areas were significantly smaller in patients with stable angina (group 1, 21.8 (11.9)) than in those with unstable angina (group 2, 31.5 (14.6); group 3, 46.4 (16.7)) (1 v 2, P < 0.02; 2 v 3, P < 0.02; 1 v 3, P < 0.001). Mean numbers of T cells per mm2 were as follows: group 1, 17 (9.4); group 2, 25 (15.9); group 3, 41 (30.6) (1 v 2, P 0.04; 2 v 3, P 0.07; 1 v 3, P < 0.001). Areas with HLA-DR positive cells showed the same pattern as macrophages and T cells and were smaller in stable (29.9 (12.4)) than in unstable angina (group 2, 40.4 (17.6); group 3, 52.4 (12.0)) (1 v 2, P < 0.02; 2 v 3, P < 0.05; 1 v 3, P < 0.001). CONCLUSION: The inverse relation between the extent of inflammatory activity in plaque tissues of culprit lesions and the clinical stability of the ischaemic syndrome supports the concept that reduction of inflammation favours plaque stabilisation. At the same time, the considerable overlap between groups indicates that patients with clinically stable angina do not all have histologically stable plaques.

Reproducibility of quantitative measurements from intracoronary ultrasound images. Beat-to-beat variability and influence of the cardiac cycle.

OBJECTIVES: The purpose of this study was to determine the variability of quantitative measurements from intracoronary ultrasound images, and the influence of the cardiac cycle on this variability, as a basis for in vivo applications. METHODS: Two observers analysed 30 MHz cross-sectional images from 96 in-vivo coronary arterial sites. By computer-assisted contour tracing we determined lumen area, vessel area, lesion area (vessel area minus lumen area) and percent obstruction (100% x lesion area/vessel area). Intra- and inter-observer and beat-to-beat variability, and systolic to diastolic differences were calculated by paired analysis. RESULTS: Consistent intra- and inter-observer differences (bias) were small (< or = 0.9%). Random variations in the two direct parameters were < or = 21.1%, but for the two derived parameters they were up to 40%. For all four parameters, random inter-observer variability was significantly greater (up to 119% for vessel area: 19.3 vs 8.8%) than intra-observer variability, but consistent variability was similar. Consistent beat-to-beat differences were small (< or = 1.4%), random variations were 8.9% to 17.5%. Random beat-to-beat variability for all four parameters was greater in diastolic than in systolic frames (up to 47.0% difference (11.9 vs 17.5%) for lesion area). Vascular dimensions were significantly greater in systole (2%). We found an error of 0.24 mm (2SD) for intra-observer variability of calculated mean arterial diameters, which is similar to the error described in angiographic studies (0.22 mm). CONCLUSIONS: Quantitative measurements from intracoronary ultrasound images generally reproduce well. It is preferable to use directly measured parameters as opposed to derived parameters, as they are less subject to variability. Variability can be reduced by selecting systolic images.

Randomised trial of excimer laser angioplasty versus balloon angioplasty for treatment of obstructive coronary artery disease.

BACKGROUND: Excimer laser coronary angioplasty is reported to give excellent procedural results for treatment of complex coronary lesions, but this method has not been compared with balloon angioplasty in a randomised trial. METHODS: Patients (n = 308) with stable angina and coronary lesions longer than 10 mm on visual assessment were included. 151 patients (158 lesions) were assigned randomly to laser angioplasty and 157 (167 lesions) to balloon angioplasty. The primary clinical endpoints were death, myocardial infarction, coronary bypass surgery, or repeat coronary angioplasty of the randomised segment during 6 months of follow-up. The primary angiographic endpoint was the minimal lumen diameter at follow-up in relation to the baseline value (net gain), as determined by quantitative coronary angiography. FINDINGS: Laser angioplasty was followed by balloon angioplasty in 98% of procedures. The angiographic success rate was 80% in patients treated with laser angioplasty compared with 79% in patients treated with balloon angioplasty. There were no deaths. Myocardial infarction, coronary bypass surgery, and repeat angioplasty occurred in 4.6%, 10.6%, and 21.2%, respectively, of the patients in the laser angioplasty group compared with 5.7%, 10.8%, and 18.5% of the balloon angioplasty group. Net mean (SD) gain in minimal lumen diameter was 0.40 (0.69) mm in patients treated with laser angioplasty and 0.48 (0.66) mm in those treated with balloon angioplasty (p = 0.34). The restenosis rate (> 50% diameter stenosis) was 51.6% in the laser angioplasty group versus 41.3% in the balloon angioplasty group (p = 0.13). INTERPRETATION: Excimer laser angioplasty followed by balloon angioplasty provides no benefit additional to balloon angioplasty alone with respect to the initial and long-term clinical and angiographic outcome in the treatment of obstructive coronary artery disease.