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Biomedical subjects

M B Leon

Publications and source records attributed to M B Leon.

At least 163 records · Page 9Linked to original sources
PubMed1998

The influence of diabetes mellitus on acute and late clinical outcomes following coronary stent implantation.

OBJECTIVES: We compared the clinical outcomes following coronary stent implantation in insulin-treated diabetes mellitus (IDDM), non-IDDM patients, and nondiabetic patients. BACKGROUND: Diabetic patients have increased restenosis and late morbidity following balloon angioplasty. The impact of diabetes mellitus (DM), especially IDDM, on in-stent restenosis is not known. METHODS: We studied 954 consecutive patients with native coronary artery lesions treated with elective Palmaz-Schatz stents implantation using conventional coronary angiographic and intravascular ultrasound methodology. Procedural success, major in-hospital complications, and 1-year clinical outcome were compared according to the diabetic status. RESULTS. In-hospital mortality was 2% in IDDM, significantly higher (p <0.02) compared with non-IDDM (0%) and nondiabetics (0.3%). Stent thrombosis did not differ among groups (0.9% in IDDM vs. 0% in non-IDDM and 0% in nondiabetics, p >0.1). During follow-up, target lesion revascularization (TLR) was 28% in IDDM, significantly higher (p <0.05) compared with non-IDDM (17.6%) and nondiabetics (16.3%). Late cardiac event-free survival (including death, myocardial infarction [MI], and any coronary revascularization procedure) was significantly lower (p=0.0004) in IDDM (60%) compared with non-IDDM (70%) and nondiabetic patients (76%). By multivariate analysis, IDDM was an independent predictor for any late cardiac event (OR=2.05, p=0.0002) in general and TLR (odds ratio=2.51, p=0.0001) in particular. CONCLUSIONS. In a large consecutive series of patients treated by elective stent implantation, IDDM patients were at higher risk for in-hospital mortality and subsequent TLR and, as a result, had a significantly lower cardiac event-free survival rate. On the other hand, acute and long-term procedural outcome was found to be similar for non-IDDM compared with nondiabetic patients.

Adult↗
PubMed1998

Validation of the in vivo intravascular ultrasound measurement of in-stent neointimal hyperplasia volumes.

OBJECTIVES: This study was undertaken to validate the in vivo intravascular ultrasound (IVUS) measurement of in-stent neointimal hyperplasia (IH) volumes. BACKGROUND: Because stents reduce restenosis compared to balloon angioplasty, stent use has increased significantly. As a result, in-stent restenosis is now an important clinical problem. Serial IVUS studies have shown that in-stent restenosis is secondary to intimal hyperplasia. To evaluate strategies to reduce in-stent restenosis, accurate measurement of in-stent neointimal tissue is important. METHODS: Using a porcine coronary artery model of in-stent restenosis, single Palmaz-Schatz stents were implanted into 16 animals with a stent:artery ratio of 1.3:1. Intravascular ultrasound imaging was performed at 1 month, immediately prior to animal sacrifice. In vivo IVUS and ex vivo histomorphometric measurements included stent, lumen and IH areas; IH volumes were calculated with Simpson's rule. RESULTS: Intravascular ultrasound measurements of IH (30.4+/-11.0 mm3) volumes correlated strongly with histomorphometric measurements (26.7+/-8.5 mm3, r=0.965, p < 0.0001). The difference between the IVUS and the histomorphometric measurements of IVUS volume was 4.1+/-2.7 mm3 or 15.8+/-11% (standard error of the estimate=0.7). Both histomorphometry and IVUS showed that IH was concentric and uniformly distributed over the length of the stent. Intravascular ultrasound detected neointimal thickening of < or =0.2 mm in 5 of 16 stents. Sample size calculations based on the IVUS measurement of IH volumes showed that 12 stented lesions/arm would be required to show a 50% reduction in IVUS-measured IH volume and 44 stented lesions/arm would be required to show a 25% reduction in IH volume. CONCLUSION: In vivo IVUS measurement of IH volumes correlated strongly with ex vivo histomorphometry. Using volumetric IVUS end points, small sample sizes should be necessary to demonstrate effectiveness of strategies to reduce in-stent restenosis.

Angioplasty, Balloon, Coronary↗
PubMed1998

Serial volumetric (three-dimensional) intravascular ultrasound analysis of restenosis after directional coronary atherectomy.

OBJECTIVES: We report the use of three-dimensional (volumetric) intravascular ultrasound (IVUS) analysis to assess serial changes after directional coronary atherectomy (DCA). BACKGROUND: Recent serial planar IVUS studies have described a decrease in external elastic membrane (EEM) area following catheter-based intervention as an important mechanism of late lumen renarrowing. METHODS: Thirty-one patients with de novo native coronary lesions treated with DCA in the Serial Ultrasound Restenosis (SURE) Trial and in Optimal Atherectomy Restenosis Study (OARS) were enrolled in this study. Serial IVUS was performed before and after intervention and at 6 months' follow-up. In a subgroup of 18 patients from the SURE trial, IVUS was also performed at 24 h and at 1 month postintervention. Segments, 20-mm-long (200 image slices), were analyzed using a previously validated three-dimensional, computerized, automated edge-detection algorithm. The EEM, lumen, and plaque+media (P+M = EEM-lumen) volumes were calculated. RESULTS: At follow-up, lumen volume was smaller than at postintervention (159+/-69 mm3 vs. 179+/-49 mm3, p = 0.0003). From postintervention to follow-up, there was a decrease in EEM volume (377+/-107 to 352+/-125 mm3, p < 0.0001), but no change in P+M volume (p = 0.52). The delta lumen volume correlated strongly with deltaEEM volume (r = 0.842, p < 0.0001), but not with deltaP+M volume. In the 18 patients from the SURE Trial, the decrease in lumen and EEM volumes occurred late, between 1 month and 6 months of follow-up. CONCLUSIONS: Volumetric IVUS analysis demonstrated that late lumen volume loss following DCA was a result of a decrease in EEM volume. This was a late event, occurring between 1 and 6 months' postintervention.

Aged↗
PubMed1998

Treatment of calcified coronary lesions with Palmaz-Schatz stents. An intravascular ultrasound study.

AIMS: To evaluate the result of coronary stenting in calcified lesions and to find morphological and procedural factors influencing the final result. METHODS AND RESULTS: Three hundred and twenty three native coronary artery lesions in 303 patients (197 men, mean age 63.9 +/- 11.5 years) treated with Palmaz-Schatz stents were differentiated into four groups depending on their degree of circumferential calcification as defined by intravascular ultrasound [0-90 degrees (n=120), 91-180 degrees (n=58, 181-270$ (n=71) and 271-360 degrees n=74)]. In 117 lesions rotational atherectomy was used prior to stent placement. Intravascular ultrasound and quantitative angiography were performed prior to treatment and after stent placement to measure minimal and maximal lumen diameter and lumen cross-sectional area at the lesion site and the reference segments. Acute lumen gain and eccentricity index were calculated. Although higher balloon pressures were used than in the minimally calcified lesions. the final angiographic minimal lumen diameter decreased with increasing arc of calcification (3.01 +/- 0.47, 3.04 +/- 0.43, 2.85 +/- 0.53, 2.83 +/- 0.40 mm, respectively, P=0.0320) resulting in a decrease in acute diameter gain with increasing arc of calcification (2.06 +/- 0.51, 1.91 +/- 0.46, 1.81 +/- 0.56, 1.78 +/- 0.51 mm, respectively, P=0.0067). Adjunctive rotational atherectomy prior to stent placement resulted in a greater acute diameter and a greater lumen cross-sectional area gain, coupled with less final residual stenosis than pre-treatment with balloon angioplasty. CONCLUSION: Implantation of stents in calcified lesions results in less optimal stent expansion, especially in lesions with thick, eccentric calcific plaque layers. Use of adjunctive rotational atherectomy before stent placement may improve the procedural result.

Aged↗
PubMed1998

Feasibility and safety of percutaneous laser revascularization using the Biosense system in porcine hearts.

BACKGROUND: Direct myocardial revascularization (DMR) is being explored to improve symptoms in patients with refractory ischemic coronary syndromes. This study assessed the safety and feasibility of percutaneous DMR using the Biosense non-fluoroscopic navigation system (incorporating the holmium : yttrium aluminium garnet laser) in pig hearts. METHODS AND RESULTS: Twenty pigs underwent left ventricular mapping using the Biosense system, followed by percutaneous DMR with a holmium : yttrium aluminium garnet laser at 2 J x 1 pulse, and were sacrificed acutely (n = 5), at 24 h (n = 5), and at 3 weeks (n = 10) after the DMR procedure. The hearts were examined grossly and microscopically. Serial creatine kinase-MB level was measured up to 24 h. There were no procedural complications. Animals received 13 +/- 2 channels in 19 +/- 7 min. The catheter was able to reach all regions, including the septum. There was no increase in creatine kinase-MB level up to 24 h. One animal died within an hour of the procedure. There was one sealed perforation into the subepicardial fat as a result of same site laser activation. Histologic evaluation in the acute and 24 h groups revealed laser channels which were 3.6 +/- 2.2 mm long, 1.5 +/- 0.7 mm wide, with an entry angle of 73 +/- 12 degrees. Channels were filled with platelet thrombi acutely and were surrounded by well-defined rims of thermal coagulation and an 'impact zone' of viable myocardium; at 3 weeks, no channels remained patent and they had been replaced by well-healed granulation tissue. CONCLUSIONS: It is feasible and safe to perform percutaneous DMR with the Biosense system and the channels created with the chosen laser parameters are rapidly sealed with platelet thrombi and at 3 weeks are replaced by well-healed granulation tissue.

Animals↗
PubMed1998

Atherosclerotic coronary lesions with inadequate compensatory enlargement have smaller plaque and vessel volumes: observations with three dimensional intravascular ultrasound in vivo.

OBJECTIVE: To compare vessel, lumen, and plaque volumes in atherosclerotic coronary lesions with inadequate compensatory enlargement versus lesions with adequate compensatory enlargement. DESIGN: 35 angiographically significant coronary lesions were examined by intravascular ultrasound (IVUS) during motorised transducer pullback. Segments 20 mm in length were analysed using a validated automated three dimensional analysis system. IVUS was used to classify lesions as having inadequate (group I) or adequate (group II) compensatory enlargement. RESULTS: There was no significant difference in quantitative angiographic measurements and the IVUS minimum lumen cross sectional area between groups I (n = 15) and II (n = 20). In group I, the vessel cross sectional area was 13.3 (3.0) mm2 at the lesion site and 14.4 (3.6) mm2 at the distal reference (p < 0.01), whereas in group II it was 17.5 (5.6) mm2 at the lesion site and 14.0 (6.0) mm2 at the distal reference (p < 0.001). Vessel and plaque cross sectional areas were significantly smaller in group I than in group II (13.3 (3.0) v 17.5 (5.6) mm2, p < 0.01; and 10.9 (2.8) v 15.2 (4.9) mm2; p < 0.005). Similarly, vessel and plaque volume were smaller in group I (291.0 (61.0) v 353.7 (110.0) mm3, and 177.5 (48.4) v 228.0 (92.8) mm3, p < 0.05 for both). Lumen areas and volumes were similar. CONCLUSIONS: In lesions with inadequate compensatory enlargement, both vessel and plaque volume appear to be smaller than in lesions with adequate compensatory enlargement.

Coronary Angiography↗
PubMed1998

Procedural and follow up results with a new balloon expandable stent in unselected lesions.

OBJECTIVE: To assess the clinical and angiographic results of the first clinical application of a new balloon expandable stent, the NIR stent, characterised by high longitudinal flexibility and low profile before expansion, and by high radial support and minimal recoil and shortening after expansion. DESIGN: Single centre survey of unselected lesions in consecutive patients. SETTING: Tertiary referral centre. PATIENTS AND LESIONS: 93 stents of various length (9, 16, and 32 mm) were implanted in 64 lesions in 41 patients. Twenty lesions (31%) were longer than 15 mm, and 17 lesions (27%) were located in vessels with a diameter smaller than 2.5 mm. Extreme tortuosity of the proximal vessel was present in 15 lesions (23%). All patients were treated with aspirin and ticlopidine. All lesions were evaluated before and after treatment by quantitative angiography, and in 47 lesions (75%) the stent expansion was also controlled by intracoronary ultrasound. Clinical follow up was available in all patients and angiographic follow up was performed in 53 lesions (84%), at a mean (SD) interval of 5.4 (1.7) months. RESULTS: Deployment of the stent failed in two lesions (3%). Minimum lumen diameter increased from 1.01 (0.54) mm to 2.94 (0.49) mm, and diameter stenosis decreased from 66(15)% to 7(11)%. There was one in-hospital non-Q wave myocardial infarction, one sudden death after 40 days, and 17 target lesion revascularisations (27%). Angiographic restenosis (> or = 50% diameter stenosis) was documented in 19 lesions (36% of all lesions with angiographic follow up), with an average residual diameter stenosis of 43(21)% and minimum lumen diameter of 1.63 (0.74) mm. Restenosis was more common in vessels with a reference diameter < 2.5 mm (45%) and for lesions longer than 15 mm (46%). CONCLUSIONS: The NIR stent could be used successfully in most lesions, achieving optimal angiographic results with very few in-hospital or subacute cardiac events. The angiographic restenosis rate and need for target lesion revascularisation remained high in this unfavourable lesion subset, especially in small vessels and long lesions.

Catheterization↗
PubMed1998

Treatment of in-stent restenosis.

Although in-stent restenosis is the result of neointimal hyperplasia, mechanical problems (e.g. stent underexpansion) that occurred during implantation may result in restenosis at follow-up. The treatment of in-stent restenosis, begins with identification of these occult mechanical problems. Thereafter, in-stent restenosis can be treated with PTCA, atheroablation, or additional stent implantation; it is nuclear which technique is superior. Not all in-stent restenosis lesions have a similar risk of recurrence. Recurrence appears to depend on several markers of biologic activity: focal vs diffuse in-stent restenosis, the first episode vs recurrent in-stent restenosis, and early vs late recurrence. Vascular brachytherapy has emerged as the most promising way to treat high-risk lesion subsets.

Angioplasty, Balloon, Coronary↗
PubMed1997

Successful directional atherectomy of de novo coronary lesions assessed with three-dimensional intravascular ultrasound and angiographic follow-up.

Recent histopathologic and intravascular ultrasound (IVUS) data indicate that inadequate compensatory enlargement of atherosclerotic lesions contributes to the development of significant arterial stenoses. Such lesions may contain less plaque, which may have implications for atheroablative interventions. In this study, we compared lesions with (group A, n = 16) and without inadequate compensatory enlargement (group B, n = 30) as determined by IVUS. The acute results and the follow-up lumen dimensions of angiographically successful directional coronary atherectomy procedures were compared. Inadequate compensatory enlargement was considered present when the preintervention arterial cross-sectional area at the target lesion site was smaller than that at the (distal) reference site. Three-dimensional IVUS analysis and quantitative angiography were performed in 46 patients before and after intervention. IVUS measurements included the arterial, lumen, and plaque (arterial minus lumen) cross-sectional areas at the target lesion site (i.e., smallest lumen site) and the (distal) reference site. Angiographic follow-up was performed in 42 patients. Preintervention and postintervention angiographic measurements and IVUS lumen cross-sectional area measurements were similar in both groups. However, at follow-up, the angiographic minimum lumen and reference diameters were significantly smaller in group A compared with group B (1.71 +/- 0.47 mm vs 2.14 +/- 0.73 mm, p <0.03, and 2.97 +/- 0.29 mm vs 3.39 +/- 0.76 mm, p <0.02; group A vs B). The data of this observational study suggest that lesions with inadequate compensatory enlargement, as determined by IVUS before intervention, may have less favorable long-term lumen dimensions after directional coronary atherectomy procedures.

Adult↗
PubMed1997

Problems in the evaluation of new devices for coronary intervention: what have we learned since 1989?

The objectives of this study are to review the problems associated with the evaluation of new devices, the progress made in that evaluation process since 1989, and the role played by the New Approaches to Coronary Intervention (NACI) registry. In 1988-1989, the first wave of new coronary devices (stents, atherectomy, laser catheters) were entering clinical investigation. It seemed unlikely that the small manufacturer-run registries used to gain approval for earlier balloon catheters would be adequate to evaluate the host of complex new devices, each of which might be used for a restricted set of anatomic indications. Moreover, the wide range of arbitrary definitions then in use for fundamental outcomes (such as success, complication, and restenosis), effectively precluded meaningful device-to-device comparisons. Against this backdrop, the NACI registry was formed with National Heart, Lung, and Blood Institute funding to provide an independent and standardized evaluation of the first 8 new devices under evaluation in the United States, across the broad range of their application. The registry employed a unique modular form set to track the sequence of events during complex cases in which serial new devices and balloon angioplasty might be used, either in a planned way, or an unplanned way (to treat complications or suboptimal results). Outcomes were subjected to standardized criteria for (1) the reason for device use (planned, unplanned); (2) success (device, lesion, and procedural success); (3) complications (a) major (death, Q-wave myocardial infarction, and emergency coronary artery bypass grafting); or (b) other (groin complications, non-wave myocardial infarction, etc.); and (4) clinical restenosis (any subsequent revascularization, target lesion revascularization). Separate funding for an angiographic core laboratory was obtained in 1992, which analyzed 3,936 (88.9%) of the 4,429 films obtained on patients enrolled between November 1990 and March 1994. The NACI registry has addressed a broad range of problems inherent in the evaluation of new devices for coronary intervention. Whereas the approval process has moved progressively towards randomized clinical trials (and away from registries), the NACI registry offers a unique view of current practice, outside the narrow scope of the limited number of randomized trials that have been performed to date. This article shows, however, that we have learned about more than the devices themselves since 1989-we have also learned about the importance of knowing the reason for device use, using precise definitions of endpoint variables, understanding the financial and reimbursement ramifications of new device trials, and upholding strict investigator ethics during the conduct of such evaluations.

Angioplasty↗
PubMed1997

Frequency and predictors of major in-hospital ischemic complications after planned and unplanned new-device angioplasty from the New Approaches to Coronary Intervention (NACI) registry.

The purpose of this study was to determine the frequency and predictors of major in-hospital ischemic complications after planned and unplanned procedures with new angioplasty devices from the New Approaches to Coronary Intervention (NACI) registry. The NACI registry is a multicenter, voluntary reporting of consecutive patients undergoing new-device angioplasty procedures using atherectomy catheters, stents, or lasers. This registry affords the opportunity to evaluate the performance of new angioplasty devices during elective and urgent circumstances. The study population consisted of 3,340 patients with 3,733 lesions (2,921 in native coronary arteries and 812 in saphenous vein grafts [SVGs], who were treated with new devices over a 3.5-year period and had their angiograms analyzed independently at a central angiographic core laboratory. Their in-hospital course and multivariate predictors of the complications in planned and unplanned procedures, further divided into native and SVG lesions, were evaluated. In 82.2% of native coronary artery lesions and 96.9% of SVG lesions, the procedure with a device had been planned due to unfavorable lesion characteristics for PTCA. In the remaining lesions, device use was unplanned, and was performed mainly to treat a suboptimal result (59-80.4%) after percutaneous transluminal coronary angioplasty (PTCA), and less frequently after important complications of PTCA including abrupt closure and PTCA failure. In native artery cohort, major in-hospital ischemic complications (death, Q-wave myocardial infarction [MI], or emergency coronary artery bypass surgery) occurred in 2.7% of the planned and 9.9% of the unplanned procedures (p < 0.001), whereas in SVG such complications occurred in 3.6% of the planned and 8.7% of unplanned procedures (p = 0.21). Multivariate analysis revealed several predictors of major ischemic complications from planned native coronary artery device use: post-MI angina (odds ratio = 2.83); severe concomitant noncardiac disease (odds ratio = 2.5); multivessel disease (odds ratio = 1.75); and de novo lesions (odds ratio = 2.3). Multivariate predictors of major complications in unplanned native coronary artery procedures included high surgical risk (odds ratio = 3.08), and tortuous lesion (odds ratio = 2.41). In SVG lesions, the independent predictors of major complications for planned procedures included age (odds ratio = 1.09), high surgical risk (odds ratio = 4.34), and thrombus (odds ratio = 2.62). In native and SVG lesions, rates of major complications of planned procedures was acceptable (2.7-3.67%), but unplanned use of a new device was associated with a significantly higher rate of in-hospital complications (approximately 9%). Multivariate predictors for major ischemic complications included both clinical and lesion characteristics, and differed for native versus SVG lesions, as well as for planned versus unplanned procedures.

Aged↗
PubMed1997

Directional coronary atherectomy (DCA): a report from the New Approaches to Coronary Intervention (NACI) registry.

Directional coronary atherectomy (DCA) with the Simpson coronary atherocath seeks to debulk rather than simply displace obstructive tissue and is a means of enlarging the stenotic coronary lumen. This report from the New Approaches to Coronary Intervention (NACI) registry describes the experience of 1,196 patients who underwent DCA as the sole treatment for either native vessel or vein graft lesions. Device success (post-DCA residual stenosis <50% and > or =20% improvement) was achieved in 87.8%, with a lesion success rate (postprocedural residual stenosis <50% and > or =20% improvement) of 94.0%. The mean resultant stenosis after all interventions (by core laboratory) was 19%. Significant in-hospital complications occurred in 2.8% of patients with DCA attempts, including death 0.6%, Q-wave myocardial infarction (MI) 1.5%, and emergent coronary artery bypass graft surgery (CABG) 2.8%. At 1-year follow-up, cumulative mortality was 3.6%, with repeat revascularization in 28% (repeat percutaneous transluminal coronary angioplasty, 20.1%; CABG, 10.6%). This reflected percutaneous or surgical revascularization of the original lesion (target lesion revascularization) in 22.6% of patients. Subgroup analysis showed a lower lesion success rate and an increased complication rate for unplanned use, vein graft treatment, and treatment of a de novo (vs a restenotic) lesion. Multivariate analysis shows that diabetes mellitus, unstable angina, treatment of a restenotic lesion, and greater residual stenosis after the initial procedure were independent predictors of the composite endpoint of death/Q-wave MI/target lesion revascularization by 1-year follow-up. Among these generally favorable acute and 1-year results, the NACI directional atherectomy data confirm the "bigger is better" hypothesis: that lesions with a lower residual stenosis after a successful procedure had significantly fewer target lesion revascularizations between 30 days and 1 year, with no increase in major adverse events.

Atherectomy, Coronary↗
PubMed1997

High-speed rotational atherectomy of human coronary stenoses: acute and one-year outcomes from the New Approaches to Coronary Intervention (NACI) registry.

High-speed rotational atherectomy (RA) is a new percutaneous procedure for treatment of coronary stenoses that operates by the unique mechanism of plaque abrasion. This article reports acute (in-hospital) outcomes and 1-year follow-up in a large cohort of patients treated with this device by NACI investigators. A total of 525 patients with 670 lesions treated with RA form the substrate of this report. Patients tended to be older (mean age 64.8 years) than those in previously reported series of percutaneous transluminal coronary angioplasty (PTCA), with more extensive disease and more complex lesions. Calcification was present in 54% of lesions, and eccentricity in 41%. Balloon angioplasty postdilation was performed after RA in 88% of cases. Angiographic and procedural success (angiographic success without death, Q-wave myocardial infarction [MI] or emergency coronary artery bypass graft [CABG] surgery) rates were 89% and 88%, respectively. Acute in-hospital events included 4 deaths (1%) and 1 emergency CABG surgery (0.4%). MI occurred in 6% of patients, consisting predominantly of non-Q-wave MI (5%). After RA, angiographic complications included coronary dissection (12%), abrupt closure (5%), side branch occlusion (3%), and distal embolization (3%). Most of these were resolved after postdilation except for coronary dissection, which was present in 15% of lesions treated. Mean length of stay was 3 days. At 1-year follow-up, 27% of patients required target lesion revascularization and 30% had experienced death, Q-wave MI, or target lesion revascularization. Preprocedural characteristics that independently predicted 1-year death, Q-wave MI, or target lesion revascularization were male gender, high risk for surgery, target lesions that were proximal to or in bifurcations, eccentric, long, or highly stenosed. RA, even when applied to lesions of traditionally unfavorable morphology, appears to provide reasonable procedural and angiographic success rates. Restenosis and progression of disease contribute to subsequent clinical and procedural events.

Aged↗
PubMed1997

Acute and long-term outcome after Palmaz-Schatz stenting: analysis from the New Approaches to Coronary Intervention (NACI) registry.

The randomized Stent Restenosis Study (STRESS) and Belgium Netherlands Stent (Benestent) trials established that elective use of Palmaz-Schatz stents (PSSs) in native coronary arteries with de novo lesions is associated with increased procedural success and reduced restenosis. However there are other clinical indications for which stents are commonly used (unplanned use, vein grafts, restenosis lesions) that are not addressed in these studies. From 1990-1992, 688 lesions in 628 patients were treated with PSSs in the New Approaches to Coronary Intervention (NACI) registry. Angiographic core laboratory readings were available for 543 patients (595 lesions, of which 106 were stented for unplanned indications, 239 were in saphenous vein bypass grafts, and 296 were previously treated). The cohort of patients in whom stents were placed for unplanned indications had more women, current smokers, and had a higher incidence of recent myocardial infarction (MI). Patients who underwent stenting of saphenous vein grafts were older, had a higher incidence of diabetes mellitus, unstable angina, prior MI, and congestive heart failure. Lesion success was similar in all cohorts (98%), but procedural success was significantly higher for planned stenting (96% vs 87%; p < 0.01). Predictors of adverse events in-hospital were presence of a significant left main stenosis and stenting for unplanned indication. The incidence of target lesion revascularization by 30 days was significantly higher for patients undergoing unplanned stenting due to a higher risk for stent thrombosis. Recent MI, stenting in native lesion, and small postprocedural minimum lumen diameter independently predicted target lesion revascularization at 30 days. Independent predictors of death, Q-wave myocardial infarction, or target lesion revascularization at 1 year included severe concomitant disease, high risk for surgery, left main disease, stenting in the left main coronary artery, and low postprocedure minimum lumen diameter.

Aged↗
PubMed1997

Excimer laser coronary angioplasty: the New Approaches to Coronary Intervention (NACI) experience.

In the New Approaches to Coronary Intervention (NACI) registry, 887 patients were electively treated with excimer laser coronary angioplasty (ELCA) for coronary artery disease. The Advanced Interventional System (AIS) system was used in 487 cases; the Spectranetics system, in 400. The mean age was 63.4 years. Most patients had unstable angina (60.3%); 43.7% had a prior myocardial infarction; and 18.6% were high risk or inoperable patients. Mean ejection fraction was 55.4%. A total of 1,000 lesions were treated in the 887 patients. Of the 1,000 lesions treated with ELCA in the 887 patients, 36% were in the right coronary artery; 33%, left anterior descending; 13%, circumflex; 3%, left main; and 16.6%, vein graft. By angiographic core laboratory analysis available for 752 (85%) patients with 839 lesions, lesions were 12.76 mm long. The minimum lumen diameter increased to 1.29 mm after the laser and finally to 1.95 mm after adjunctive percutaneous transluminal coronary angioplasty (PTCA) (which was performed in 93% of all lesions), with a final residual stenosis of 32.1% and Thrombolysis in Myocardial Infarction (TIMI) grade 3 flow in 95%. Dissections of grades B, C, or D were seen after 22.0% of initial laser attempts, and postlaser perforations were noted in 2.6%. Additional such dissections accumulated after adjunctive PTCA but the perforation rate remained low. Procedural success was achieved in 84% of patients, but 1.2% died, 0.7% experienced Q-wave myocardial infarction (MI), and 2.7% required emergency bypass surgery. Multiple logistic regression analysis could not identify any independent predictors of these in-hospital complications. One-year mortality was 5.7% and the cumulative incidence of Q-wave MI was 1.5%. Coronary artery bypass graft (CABG) surgery was performed in 15.0% of patients whereas 25.5% required repeat percutaneous intervention with a target lesion revascularization rate of 31%. Independent predictors of death, Q-wave MI, or target lesion revascularization (which, combined, occurred in 35.6% of patients) were the absence of prior MI, ELCA in the circumflex, perforation after the procedure, and small (<2 mm) final minimal lumen diameter. Considering the large number of patients with high-risk lesions, laser angioplasty was performed with excellent procedural success rates and a reasonable incidence of major complications.

Aged↗