The immediate and long-term effect of optimal balloon angioplasty on the absolute coronary blood flow velocity reserve. A subanalysis of the DEBATE study. Doppler Endpoints Balloon Angioplasty Trial Europe.

BACKGROUND: There are limited data regarding the immediate and long-term effect of balloon angioplasty on the coronary flow reserve evaluated in a multicentre setting. METHODS AND RESULTS: A total of 86 patients with one-vessel disease and normal left ventricular function were analysed before and after optimal balloon angioplasty (diameter stenosis <35%) and at 6-month follow-up. Coronary flow reserve was assessed with a Doppler guide wire. A low coronary flow reserve (2.5 (46% vs 23% and 36% vs 16%, respectively; P<0.05) due to a trend towards restenosis (29% vs 16%; P=0.15) or a low coronary flow reserve at follow-up due to persistent elevated baseline blood flow velocity. Patients without restenosis showed a decrease or increase of coronary flow reserve during follow-up, determined by alterations of hyperaemic blood flow velocity. CONCLUSIONS: Patients with an impaired coronary flow reserve directly after optimal balloon angioplasty showed a higher target lesion revascularization rate compared to patients with a coronary flow reserve >2.5. This patient group consists of patients prone to develop restenosis, while other patients are characterized by a persistently low coronary flow reserve, probably secondary to disturbed autoregulation and/or diffuse mild coronary atherosclerosis. Coronary flow reserve alterations in patients without restenosis were related to changes in hyperaemic blood flow velocity, suggesting that this phenomenon relates to epicardial remodelling.

Angiographical and Doppler flow-derived parameters for assessment of coronary lesion severity and its relation to the result of exercise electrocardiography. DEBATE study group. Doppler Endpoints Balloon Angioplasty Trial Europe.

AIMS: Evaluation of angiographical and intracoronary Doppler-derived parameters of coronary stenosis severity. METHODS AND RESULTS: A total of 225 patients with one-vessel disease were studied before PTCA and at 6 months follow-up. Exercise electrocardiography was performed to document presence (n = 157) or absence (n = 138) of an ST segment shift (> or =0.1 mV). Intracoronary blood flow velocity analysis was performed to determine the proximal/distal flow velocity ratio, the distal diastolic/systolic flow velocity ratio and coronary flow velocity reserve. Receiver operator characteristic curves were calculated to assess the predictive value of these variables compared with the exercise test. The distal coronary flow velocity reserve demonstrated the best linear correlation for both percentage diameter stenosis and minimum lumen diameter (r = 0.67 and r = 0.66; P<0.01), compared to the diastolic/systolic flow velocity ratio (r = 0.19 and r = 0.14; P<0.01) and the proximal/distal flow velocity ratio (r = 0.03 and r = 0.07; not significant). The areas under the curve were 0. 84+/-0.02; 0.82+/-0.03 and 0.83+/-0.03 for diameter stenosis, minimum lumen diameter and coronary flow velocity reserve, respectively. Logistic regression analysis revealed that the percentage diameter stenosis or minimum lumen diameter and coronary flow velocity reserve were independent predictors for the result of stress testing. CONCLUSIONS: The distal coronary flow velocity reserve is the best intracoronary Doppler parameter for evaluation of coronary narrowings. Angiographical estimates of coronary lesion severity and distal coronary flow velocity reserve are good and independent predictors for the assessment of functional severity of coronary stenosis, emphasizing the complementary role of these parameters for clinical decision making.

Health care in France: recent developments.

Health care in France falls almost exclusively under the responsibility of the Social Security department, which covers almost all the expenditures related to health care, whether hospitalization or medication is concerned. For severe diseases or surgery the coverage is likely to reach as much as 100%. The medical expenditures for several severe diseases, such as cancer, myocardial infarction, or neurodegenerative diseases are 100% covered for a period of time as long as three months. For some procedures, full coverage may be achieved by using a subscription to private health care insurance. Access to cover by the state has recently been opened to anyone living in France, after passage of a special law. There is still a lack of intensive care and hospice beds, given the rapidly increasing number of elderly who cannot be maintained at home. There is a tendency to reduce the number of beds in private and public hospitals due to the great number of such institutions and the general concern that a low volume of procedures, associated with inexperienced health care professionals, is likely to increase morbidity and mortality as well as public health care expenditure. Patients are still free to choose doctors and hospitals (whether private or public), provided that beds are available and that specific procedures can be carried out in the vicinity. So far no waiting list is needed, except for specific procedures performed by a few specialists of high repute. Health care expenses are increasing continuously, which results in a very expensive system in France.

Prognostic value of intracoronary flow velocity and diameter stenosis in assessing the short- and long-term outcomes of coronary balloon angioplasty: the DEBATE Study (Doppler Endpoints Balloon Angioplasty Trial Europe).

BACKGROUND: The aim of this prospective, multicenter study was the identification of Doppler flow velocity measurements predictive of clinical outcome of patients undergoing single-vessel balloon angioplasty with no previous Q-wave myocardial infarction. METHODS AND RESULTS: In 297 patients, a Doppler guidewire was used to measure basal and maximal hyperemic flow velocities proximal and distal to the stenosis before and after angioplasty. In 225 patients with an angiographically successful percutaneous transluminal coronary angioplasty (PTCA), postprocedural distal coronary flow reserve (CFR) and percent diameter stenosis (DS%) were correlated with symptoms and/or ischemia at 1 and 6 months, with the need for target lesion revascularization, and with angiographic restenosis (defined as DS > or = 50% at follow-up). Logistic regression and receiver operator characteristic curve analyses were applied to determine the prognostic cutoff value of CFR and DS separately and in combination. Optimal cutoff criteria for predictors of these clinical events were DS, 35%; CFR, 2.5. A distal CFR after angioplasty > 2.5 with a residual DS < or = 35% identified lesions with a low incidence of recurrence of symptoms at 1 month (10% versus 19%, P=.149) and at 6 months (23% versus 47%, P=.005), a low need for reintervention (16% versus 34%, P=.024), and a low restenosis rate (16% versus 41%, P=.002) compared with patients who did not meet these criteria. CONCLUSIONS: Measurements of distal CFR after PTCA, in combination with DS%, have a predictive value, albeit modest for the short- and long-term outcomes after PTCA, and thus may be used to identify patients who will or will not benefit from additional therapy such as stent implantation.

Role of coronary artery lumen enlargement in improving coronary blood flow after balloon angioplasty and stenting: a combined intravascular ultrasound Doppler flow and imaging study.

OBJECTIVES: This study sought to examine the mechanism of increasing coronary flow reserve after balloon angioplasty and stenting. BACKGROUND: Coronary vasodilatory reserve (CVR) does not improve after percutaneous transluminal coronary angioplasty in > or = 50% of patients, postulated to be due to impaired microvascular circulation or inadequate lumen expansion despite adequate angiographic results. METHODS: To demonstrate the role of coronary lumen expansion, serial coronary flow velocity (0.014-in. Doppler guide wire) was measured in 42 patients before and after balloon angioplasty and again after stent placement. A subset (n = 17) also underwent intravascular ultrasound (IVUS) imaging of the target sites after angioplasty and stenting. CVR (velocity) was computed as the ratio of adenosine-induced maximal hyperemic to basal average peak velocity. RESULTS: The percent diameter stenosis decreased from (mean +/- SD) 84 +/- 13% to 37 +/- 18% after angioplasty and to 8 +/- 8% after stenting (both p < 0.05). CVR was minimally changed from 1.70 +/- 0.79 at baseline to 1.89 +/- 0.56 (p = NS) after angioplasty but increased to 2.49 +/- 0.68 after stent placement (p < 0.01 vs. before and after angioplasty). IVUS lumen cross-sectional area was significantly larger after stenting than after angioplasty (8.39 +/- 2.09 vs. 5.10 +/- 2.03 mm2, p < 0.05). Anatomic variables were related to increasing coronary flow velocity reserve (CVR vs. IVUS lumen area: r = 0.47, p < 0.005; CVR vs. quantitative coronary angiographic percent area stenosis: r = 0.58, p < 0.0001). CONCLUSIONS: In most cases, increases in CVR were associated with increases in coronary lumen cross-sectional area. These data suggest that impaired CVR after angioplasty is often related to the degree of residual narrowing, which at times may not be appreciated by angiography. A physiologically complemented approach to balloon angioplasty may improve procedural outcome.

Angioscopy variables predictive of early angiographic outcome after excimer laser-assisted coronary angioplasty.

This study attempted to determine whether anatomic findings at angioscopy were associated with adverse early angiographic outcomes following excimer laser-assisted coronary angioplasty. Predictive factors of either coronary abrupt vessel closure or early (< or =24 hours) restenosis after percutaneous coronary angioplasty, including clinical and angiographic variables, have been widely evaluated. The role of angioscopic findings may contribute to identification of patients at risk for early poor outcome. Thirty-seven patients with severe lesions, including 23 total occlusions which underwent successful percutaneous transluminal coronary angioplasty (PTCA) with laser irradiation and adjunctive balloon dilatation (n = 35), or stand alone laser (n = 2), had concomitant angioscopic imaging of the target vessel. All patients had a 24-hour angiographic follow up. Early unfavorable outcome (n = 15) was defined as abrupt vessel closure or restenosis (> or = 50% stenosis) at 24 hours. By multivariate logistic regression analysis, immediate post-PTCA residual percent stenosis was associated with a poor outcome (restenosis: 33 +/- 22% vs no restenosis: 21 +/- 14%, p = 0.05). Angioscopic red thrombus aspect was the most significant correlate for early closure or restenosis (7 of 15 patients with unfavorable outcome vs 2 of 22 patients with favorable outcome, odds ratio, 22.9; p < 0.01) and was associated with a significantly higher early minimal lumen diameter loss (1 +/- 0.8 mm in the presence of a red thrombus vs 0.3 +/- 0.5 mm without thrombus, p < 0.005). Red thrombus appearance is associated with an unfavorable early angiographic outcome in patients who undergo laser-assisted coronary angioplasty.

Sympathetic stimulation overrides flow-mediated endothelium-dependent epicardial coronary vasodilation in transplant patients.

BACKGROUND: Abnormal coronary vasomotor responses have been described in transplant patients. The aim of this study was to evaluate the graft epicardial vasomotor responses to different stimuli that increase coronary blood flow. METHODS AND RESULTS: Twelve heart transplant recipients with angiographically normal epicardial coronary arteries were compared 2.7 +/- 1.2 months after surgery with 6 control subjects. Coronary flow velocity was measured with a guidewire Doppler. Coronary diameter changes of the proximal and midportion of the left anterior descending coronary artery were assessed by quantitative coronary angiography during rapid atrial pacing, cold pressor test, supine exercise, and subselective infusion of papaverine and after intracoronary injection of linsidomine (SIN-1). Catecholamine plasmatic levels were determined at the different stages of the protocol. In 6 other transplant patients, a cold pressor test was performed before and after intracoronary infusion of phentolamine (10 micrograms.kg-1.min-1). Coronary flow velocity increased significantly in both groups during each phase of the protocol. In control subjects, dilation was observed in response to atrial pacing (8.7 +/- 7.6%; P < .05), CPT (8.8 +/- 2.3%; P < .01), exercise (14.5 +/- 9.4%; P < .001), and papaverine infusion (14.2 +/- 6.1%; P < .001) and after injection of SIN-1 (26.8 +/- 11.9%; P < .001). In transplant patients, similar dilation was observed during atrial pacing (8.2 +/- 8.3%; P < .05) and papaverine infusion (14.6 +/- 7.8%; P < .001) and after SIN-1 (25.8 +/- 10.8%; P < .001). CPT and exercise caused slight constriction (-3.5 +/- 4.5% and -2.7 +/- 10.5%, respectively; both P < .001 versus control subjects). Norepinephrine plasmatic levels increased in both groups during CPT and exercise. Slight constriction during the cold pressor test (-4.5 +/- 9.6%) changed to dilation (6.8 +/- 7.0%) after alpha-blockade with phentolamine (P < .001). CONCLUSIONS: These results show that flow-mediated, endothelium-dependent vasodilation is preserved early after trans-plantation. Sympathetic stimulation, which overrides the endothelium-dependent mechanism, can be related to hypersensitivity to catecholamines due to denervation.

Repeated coronary artery occlusions during routine balloon angioplasty do not induce myocardial preconditioning in humans.

OBJECTIVES: The purpose of the present study was to assess whether brief, repeated coronary artery occlusions during balloon angioplasty induce a myocardial ischemic protective effect. BACKGROUND: In animals, brief coronary artery occlusions preceding a more prolonged occlusion result in reduced infarct size. Whether myocardial protection against ischemia could also occur in humans during angioplasty remains controversial. METHODS: Thirteen patients with a proximal left anterior descending coronary artery stenosis with no angiographic collateral circulation underwent percutaneous transluminal coronary artery balloon angioplasty. Three 120-s balloon inflations separated by a 5-min equilibration period were performed. For each inflation, intracoronary ST segment modifications, septal wall thickening (M-mode echocardiography), left ventricular pressures and time derivatives were measured at baseline and at 30, 60 and 90 s after balloon inflation and 120 s after balloon deflation. RESULTS: Intracoronary electrocardiographic analysis showed that the time course of the maximal ST segment elevation was identical at each inflation, as were wall motion changes assessed by the decrease in septal wall thickening. For the first and last inflations, peak positive dP/dt decreased significantly by 13 +/- 9% (mean +/- SD) and 14 +/- 13%, whereas peak negative dP/dt increased by 23 +/- 15% and 22 +/- 10%, respectively (all p < 0.01 from baseline values). The relaxation time constant, tau, was altered similarly during the different inflations, from 44 +/- 6 to 74 +/- 13 ms and from 57 +/- 13 to 77 +/- 13 ms (all p < 0.001) for the first and last inflations, respectively. Left ventricular end-diastolic pressure increased to the same level after each inflation. In contrast to other hemodynamic variables, tau and left ventricular end-diastolic pressure did not return to baseline values in between the inflations, which may be due to myocardial stunning. CONCLUSIONS: In patients with proximal left anterior descending coronary artery stenosis and no evidence of collateral circulation, brief periods of ischemia, such as those used during routine coronary balloon angioplasty, do not provide any protection against myocardial ischemia.

Coronary laser angioplasty.

Balloon angioplasty was introduced among the armament of therapy for coronary heart disease in 1977 by Gruentzig in Zurich. Since the first case was successful, this method of treatment spread out rapidly so that at the present time, more than 400,000 procedures are being performed per year in the U.S. The reasons for such on explosive success includes the relative safety of the procedure, the reduction in cost as compared to surgical bypass procedures, the short in-hospital stay, and short recovery time.

Comparison of the effects of exercise and cold pressor test on the vasomotor response of normal and atherosclerotic coronary arteries and their relation to the flow-mediated mechanism.

This study was designed to assess the vasomotor response of coronary arteries to exercise and the cold pressor test, and its relationships with the endothelium-mediated dependent mechanism. Twenty-two patients were entered in the study. Group I was composed of 12 patients with a total cholesterol level < 200 mg/dl associated with angiographically smooth, normal coronary arteries. Group 2 consisted of 10 patients with both a cholesterol level > 240 mg/dl and angiographic luminal irregularities of the left anterior descending coronary artery. Coronary blood flow was assessed by a 0.018-inch tip guidewire during Doppler ultrasonography, and analysis of the coronary arterial dimension of the midportion of the left anterior descending coronary artery was performed by quantitative coronary angiography. Catecholamine concentrations were assessed at the different stages of the protocol. The rate-pressure product increased during both the cold pressure test and exercise (p < 0.001). Coronary blood flow velocity increased during the cold pressor and exercise tests by 24.5 +/- 10% and 72 +/- 42%, respectively (p < 0.001), and by 127 +/- 62% (p < 0.0001) after administration of papaverine. In group 1, the cold pressor test had a more pronounced vasodilating effect on epicardial coronary arteries (+11.2 +/- 16%) compared with group 2 (-2 +/- 9%, p < 0.05). Similarly, exercise had a vasodilating action in group 1 (11.3 +/- 15%) compared with group 2 (-1.9 +/- 8%, p < 0.05). Both responses were highly correlated (r = 0.92, p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

Improvement of subendocardial myocardial perfusion after percutaneous transluminal coronary angioplasty. A myocardial contrast echocardiography study with correlation between myocardial contrast reserve and Doppler coronary reserve.

BACKGROUND: After angioplasty coronary reserve improves but does not normalize in most patients. The purpose of this study was to examine before and after angioplasty coronary reserve and transmural myocardial blood flow distribution using myocardial contrast echocardiography. METHODS AND RESULTS: Twelve patients with left anterior descending coronary artery stenosis were investigated before and immediately after angioplasty. A Doppler catheter was placed in the proximal segment. Myocardial contrast echocardiography was performed by imaging the septum in M mode in a parasternal view using a 3.0-mL bolus of sonicated amidotrizoate sodium meglumine through the guiding catheter. The gray level before injection was subtracted from the gray level after injection to maximize contrast time-intensity curves. The area under the curve was used as an indicator of myocardial blood flow, and subendocardial/subepicardial ratios were measured. After baseline measurements were obtained, Doppler and echographic data were recorded after a bolus infusion of papaverine into the left main coronary artery. The same protocol was performed in patients after angioplasty and in five control subjects with normal coronary arteries. Before angioplasty, echocardiographic and Doppler coronary reserve were 2.57 +/- 0.48 and 2.54 +/- 0.57, respectively. Both increased after angioplasty to 3.65 +/- 0.57 and 3.36 +/- 0.70, respectively (P < .05). Coronary reserve values obtained in patients with these two methods under the different conditions and in control subjects were correlated (r = .81; P = .0001). Before angioplasty, subendocardial/subepicardial septal ratios decreased from 0.80 +/- 0.48 to 0.60 +/- 0.27 after papaverine (P < .05). However, after angioplasty, these ratios tended to increase, from 0.72 +/- 0.27 to 0.92 +/- 0.45 after papaverine, but they did not change in control subjects (1.11 +/- 0.23 to 0.92 +/- 0.11). CONCLUSIONS: These results show that myocardial contrast echocardiography yields flow reserve values that correlate with values obtained using intracoronary Doppler. This technique may be considered as an accurate tool to assess coronary reserve in humans.

[Coronary disease: should images be treated?]. / Maladie coronaire: faut-il traiter des images?

Precise digitized images of the coronary arteries displaying the dimensions of high risk stenoses and giving objective measurements of their contours and density can be provided by coronarography. On-line angioscopic images of tissue flaps floating in the lumen, recent or structured thrombi, artery wall dissections, plaque ruptures, deep fissurations and sub-intimal haemorrhages demonstrate, in live colour, the pathophysiological mechanisms of coronary artery stenosis. Histological sections of the artery wall, without biopsy, can be visualized with endocoronary echography offering a global view of the wall and differentiating all the physiological layers including the intima and the internal elastic lamina, the blood-wall interface, the media and the adventitia. Our technical imaging capacity is impressive, but is anatomic imaging synonymous with coronary circulation? Certainly not. Sophisticated imaging techniques have led us to associate the severity of the stenosis with its effect on myocardial irrigation, but today therapeutic decisions require not only considering coronary anatomy but also downstream consequences which can be evaluated by measuring coronary artery flow on both sides of the stenosis. Carried on the tip of the angioplasty guide, a piezo-electric crystal emits and receives a Doppler signal. The data is processed in real time giving a complete pattern of blood flow velocity and describing diastolic and systolic flow, differences between upstream and downstream flow, and the effect of pharmacological or physiological tests such as maximal dilatation to measure coronary vascular reserve. Transstenosic pressure measurements complete the diagnostic armentorium. Thus therapeutic decisions can now be made not only on the basis of precise anatomic imaging, but also on functional imaging, giving a complete view of the pathophysiology of the coronary arteries and the effect of disease on myocardial blood supply. It is now up to us to optimize these imaging techniques and to propose treatments which provide patients with coronary artery disease with the best benefit-risk-cost ratio.

In vitro study of a radiofrequency guidewire aimed at recanalization of totally occluded peripheral arteries.

A novel radiofrequency ablative system (40 msec-train pulses with twenty 200 msec pulses at the carrier frequency of 750 KHz and 1 Hz repetition rate) aimed at recanalizing totally occluded peripheral arteries was investigated by means of in vitro tissue ablation from human postmortem arterial wall samples. The samples were submitted to irradiation with a guidewire 150 cm long, maximum diameter of ceramic tip 0.033 inch positioned perpendicular to the tissue surface in saline, contrast medium or blood using varying generator power. Ablation efficacy was determined as the depth of vaporization per pulse delivered. Electrical current for the train duration was measured as voltage at the 1 ohm-resistor. In saline, the ablation efficacy increased from 8 to 65 microns/pulse with generator power increasing from 11 W to 27.5 W. There was no significant difference in the ablation efficacy between saline and blood. In contrast medium, the ablation efficacy was significantly lower. For the same generator power, the electrical current varied during the ablation procedure from 1.3 +/- 0.2 A at the beginning of the procedure to 1.1 +/- 0.2 A after the first pulses and to 2.0 A before artery wall perforation occurred. Neither tissue ablation nor current variations were observed when radiofrequency energy was emitted on calcified tissue. The diameter of craters was 0.89 +/- 0.1 mm (range: 0.85-0.96 mm). No major thermal injury such as carbonization or charring was observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Assessment of a percutaneous Hemopump in high risk coronary angioplasty patients.

This study assessed the safety and efficacy of a new 14 Fr Hemopump device. Ten high risk patients requiring percutaneous transluminal coronary angioplasty (PTCA) (last remaining patent vessel or low left ventricular ejection fraction) underwent PTCA with the prophylactic use of the Hemopump. This device was inserted percutaneously through the femoral artery using a 16 Fr sheath and placed into the left ventricle. Hemodynamic parameters (pulmonary capillary wedge pressure, cardiac output, mean aortic pressure) were recorded before, during, and after PTCA when the Hemopump was on and off. Adequate placement of the Hemopump was obtained in all patients with moderate temporary rhythm instability, and PTCA was performed in all patients. Under assist, pulmonary capillary wedge pressure was 22 +/- 8 mmHg, compared with 29 +/- 7 mmHg (P < 0.05), whereas no significant change in other hemodynamic parameters was observed. One patient experienced ventricular fibrillation twice during PTCA, which was correlated by electrical cardioversion. During this temporary cardiac arrest, the aortic blood pressure was maintained at 50 mmHg with the Hemopump. For all patients, the Hemopump was withdrawn 15 min after the end of PTCA, and the sheath was removed 4-6 hr later. However, two patients required surgical sheath removal. One patient died of cardiogenic shock in the intensive care unit. Other patients were discharged 3 days after the procedure. Long-term follow-up shows eight surviving patients. These data show that 1) the 14 Fr percutaneous Hemopump is safe, and 2) can unload the left ventricle during PTCA while maintaining mean aortic pressure and cardiac output.

Percutaneous angioscopy in patients with restenosis after excimer laser coronary angioplasty.

Coronary angioscopy was performed in two patients with restenosis after excimer laser coronary angioplasty to improve our knowledge of restenosis after excimer laser angioplasty. The characteristics of the angioscopic findings in restenosis after excimer laser angioplasty consisted of smooth white plaques, which were distinctly different from the yellow plaques commonly observed in primary lesions. These findings indicate that restenosis in these patients after excimer laser angioplasty may be associated with smooth muscle cell proliferation and fibrosis.

Acute complications of excimer laser coronary angioplasty: a detailed analysis of multicenter results. Coinvestigators of the U.S. and European Percutaneous Excimer Laser Coronary Angioplasty (PELCA) Registries.

OBJECTIVES: The aim of this study was to document and analyze the incidence and consequences of complications of excimer laser coronary angioplasty. BACKGROUND: Excimer laser coronary angioplasty has been reported to be a safe and feasible alternative or adjunct to conventional balloon angioplasty, but serious and unique complications have been observed. METHODS: Data on 1,595 interventions of excimer laser coronary angioplasty in 1,521 patients were analyzed, using a merged data base from the U.S. and European Percutaneous Excimer Laser Coronary Angioplasty (PELCA) registries. RESULTS: Procedural success was achieved in 89.3% of interventions. Stand-alone laser angioplasty was performed in 17.8% of interventions. Complications included dissection (22.0%), vasospasm (6.1%), filling defects (4.8%), abrupt reclosure (6.1%), embolization (2.3%), perforation (2.4%), arrhythmia (0.7%) and aneurysm formation (0.3%). Major complications were non-Q wave myocardial infarction (2.3%), Q wave myocardial infarction (1.0%), coronary artery bypass grafting (3.1%) and death (0.7%). Logistic regression analysis revealed correlation between dissections and the use of larger catheter size (p = 0.0005), high energy per pulse levels (p = 0.0001 for native vessels), lesion length > 10 mm (p = 0.001) and presence of a side branch (p = 0.01). The incidence of perforations was higher in women (p = 0.004), in treatment of total occlusions (p = 0.02) and in the presence of a side branch (p = 0.03). Fatal complications were correlated with patients with multivessel disease (p < 0.0001), patients with acute myocardial infarction (p = 0.0009) and older patients (> 70 years old, p = 0.004). The incidence of major complications decreased after performance of 50 laser angioplasty procedures at one institution (p = 0.02). CONCLUSIONS: This analysis defines both the learning curve and the profile of complications for excimer laser angioplasty and provides insight into the selection of appropriate patients and proper performance of the procedure.

Angioscopy after laser and balloon coronary angioplasty.

OBJECTIVES: Percutaneous intracoronary angioscopy was used to study the morphologic changes occurring in coronary arteries after balloon or laser angioplasty. BACKGROUND: Angioscopy is thought to provide details of the coronary vessel lumen and the inner wall. METHODS: Coronary lesions were studied in 44 patients with a 4.5F Imagecath angioscope before and after each interventional procedure. Balloon and laser angioplasty were performed in 21 (group I) and 23 patients (group II), respectively. There was no difference in age, gender or angiographic lesion appearance before the procedure between the two groups. RESULTS: Circumferential visualization of the target lesion was successfully completed in 17 group I and 19 group II patients. A larger lumen than that observed at baseline was seen in all 17 group I and in 13 of the 19 group II patients. Tissue remnants were observed in all group I and II patients. Laser irradiation resulted in characteristic sharp-edged craters. Dissection was identified in 2 of 19 patients before versus 9 of 19 patients after balloon angioplasty (p < 0.05) and in 0 of 23 patients before versus 4 of 23 patients after laser angioplasty (p = NS). Subintimal hemorrhage was observed in 3 of 19 patients before versus 11 of 19 patients after balloon angioplasty (p < 0.05) and in 2 of 23 patients before versus 4 of 23 patients after laser angioplasty (p = NS). The frequency of hemorrhage was higher in group I than in group II (11 of 19 vs. 4 of 23, respectively, p < 0.02). CONCLUSIONS: Angioscopy provides valuable information on lesion morphology after coronary interventions. Balloon dilation results in a high rate of dissection and subintimal hemorrhage. Laser angioplasty is able to ablate obstructing tissue and results in a lower rate of subintimal hemorrhage than balloon dilation.