Search PubMed⌕ Search

Biomedical subjects

K M Kent

Publications and source records attributed to K M Kent.

At least 91 records · Page 5Linked to original sources
PubMed1998

Procedural results and late clinical outcomes after placement of three or more stents in single coronary lesions.

BACKGROUND: Previous reports have suggested higher procedural and long-term complications among patients treated with multiple stents for diffuse lesions and/or long dissections. METHODS AND RESULTS: To evaluate procedural success, major complications, and clinical outcomes (> or = 1 year) in a consecutive series of patients treated with multiple (> or = 3) contiguous stents in single lesions, we evaluated in-hospital and long-term (1-year) clinical outcomes in 117 consecutive patients treated with > or = 3 coronary stents compared with a concurrent series of patients treated with 1 or 2 stents (n=1673) between January 1, 1994, and December 31, 1995. Multiple stents were implanted more often in larger vessels, in the right coronary artery or saphenous vein grafts, and for unfavorable lesion characteristics, including long (>20 mm), calcified, ulcerated, thrombotic, and/or flow-obstructing lesions. Overall procedural success was obtained in 97.4% of patients and was similar whether 1 or 2 versus > or = 3 stents were used. Non-Q-wave MI (CK-MB > or = 5 times normal) was more frequent after > or = 3 stents (22.8% versus 13.4%, P=.005). Target lesion revascularization (TLR) was 14.6% for 1 or 2 stents and 13.3% for > or = 3 stents (P=.70). There was no difference in death (2.2% versus 0.9%, P=.34) or Q-wave MI (1.4% versus 0.9%, P=.64) between the two groups (1 or 2 stents versus > or = 3 stents, respectively), and overall cardiac event-free survival was similar during follow-up (P=.70). CONCLUSIONS: Patients treated with multiple (> or = 3) contiguous stents compared with 1 or 2 stents have (1) similar in-hospital procedural success and major complications despite having more unfavorable lesion characteristics, (2) a higher rate of procedural non-Q-wave MI, and (3) similar TLR and overall major cardiac event rates during 1 year of follow-up.

Aged↗
PubMed1998

In-stent restenosis: the Washington Hospital Center experience.

In-stent restenosis has become a significant clinical problem. In 1997 alone, it is estimated that up to 100,000 patients world-wide with in-stent restenosis were treated. Serial intravascular ultrasound (IVUS) analysis has shown that tubular-slotted stents almost never chronically recoil and that neointimal hyperplasia is responsible for in-stent restenosis. With the rapid recent explosion in stent use, information about in-stent restenosis has lagged behind, especially on the impact of new stent designs. For example, the true prevalence of in-stent restenosis (1) varies with the lesion and patient subset, being much higher in the "real world" than in the selected patients typically enrolled in many studies; and (2) depends on its definition (i.e., clinical vs angiographic, intralesion vs in-stent). "Conventional" catheter-based treatments have included percutaneous transluminal coronary angioplasty (PTCA), rotational atherectomy, excimer laser coronary angioplasty, directional coronary atherectomy, and additional stent implantation. Rates of recurrence with these approaches are not known and vary considerably among series; however, certain lesions seem likely to recur regardless of the treatment modality. Recently, brachytherapy has emerged as the most promising way to treat in-stent restenosis.

Angioplasty, Balloon, Coronary↗
PubMed1998

Comparative early and nine-month results of rotational atherectomy, stents, and the combination of both for calcified lesions in large coronary arteries.

The aim of this study was to determine the preferred treatment modality for calcified lesions in large (> or = 3 mm) coronary arteries, resulting in the largest lumen dimensions and the most favorable late clinical responses. Three hundred six lesions in 306 patients (223 men, mean age 66 +/- 11 years) were treated with either rotational atherectomy plus adjunct balloon angioplasty (n = 147), Palmaz-Schatz stents (n = 103), or a combination of rotational atherectomy plus adjunct Palmaz-Schatz stents (n = 56). The procedural success rate was 98.0% to 98.6% for each treatment modality. Minimal lumen diameter (MLD) before therapy was similar for all therapies. Final MLD after combination of rotational atherectomy plus Palmaz-Schatz stents was larger than after stent therapy or rotational atherectomy plus balloon angioplasty (3.21 +/- 0.49 mm, 2.88 +/- 0.51 mm, and 2.29 +/- 0.55 mm, respectively, p <0.0001). Correspondingly, final percent diameter stenosis was lowest after the combination of rotational atherectomy plus stent therapy, and significantly higher for stents or rotational atherectomy plus balloon angioplasty (4.2 +/- 15.3%, 14.1 +/- 13.3%, and 26.7% +/- 16.9%, respectively, p <0.0001). Event-free survival at 9 months was higher for patients treated with the combination of rotational atherectomy plus stents than either stent therapy or rotational atherectomy alone (85%, 77%, and 67%, respectively, log-rank p = 0.0633). The only significant independent predictor of an event during the 9-month follow-up period was the MLD after intervention (odds ratio 0.495, 95% confidence interval 0.308 to 0.796, p = 0.0037). We conclude that preatheroablation using rotational atherectomy, followed by adjunct stent placement for calcified lesions in large arteries, is associated with infrequent complications, the largest acute angiographic results, and the most favorable late clinical event rates.

Aged↗
PubMed1998

Interrelation of coronary angiographic reference lumen size and intravascular ultrasound target lesion calcium.

Intravascular ultrasound (IVUS) detects target lesion calcium twice as often as does coronary angiography. Target lesions in smaller vessels are thought to be more calcified than target lesions in large vessels. This study determined whether the presence and magnitude of target lesion calcium is related to angiographic reference lumen size. Preintervention IVUS imaging and coronary angiography were performed to study 1,454 non-aortoostial native vessel lesions in 1,342 patients. Target lesions and reference segments were evaluated according to previously published methods and are presented as mean +/- 1 SD. By angiography, 37% of lesions contained calcium, and 68% of calcium-containing lesions were classified as moderately calcified, and 32% as severely calcified. There was no relation between angiographic reference lumen size and angiographic calcium detection (p = 0.7066) or classification (none/mild vs moderate vs severe, p = 0.8135). By IVUS, 73% of lesions contained calcium. There was a consistent relation between decreasing angiographic reference lumen size and increasing IVUS lesion-associated calcium: the presence of any calcium (p = 0.0122), arc of calcium (p = 0.002), percent of lesions with an arc of calcium > 180 degrees (p = 0.0018), length of calcium (p < 0.0001), presence of any superficial calcium (p < 0.0001), arc of superficial calcium (p < 0.0001), percent of lesions with an arc of superficial calcium > 180 degrees (p = 0.0021), and length of superficial calcium (p < 0.0001). This was especially true for arteries with an angiographic reference lumen dimension < 2.00 mm. There is a distinct relation between decreasing angiographic reference lumen size and increasing lesion calcium, most striking in vessels < 2.00 mm. This increased target lesion calcium in small vessels is not seen angiographically.

Aged↗
PubMed1998

'Optimal' directional coronary atherectomy: final results of the Optimal Atherectomy Restenosis Study (OARS).

BACKGROUND: Previous clinical trials of directional coronary atherectomy (DCA) have failed to show significant improvement in early or late outcomes compared with balloon angioplasty (PTCA). The present study tested the hypothesis that more aggressive "optimal" atherectomy could be performed safely to produce larger initial lumen diameters and a lower late restenosis rate. METHODS AND RESULTS: The present study was a prospective multicenter registry of consecutive patients undergoing optimal DCA of de novo or restenotic lesions in 3.0- to 4.5-mm native coronary arteries. Optimal DCA was defined as using a 7F atherectomy device and adjunctive PTCA if necessary to achieve a < 15% residual stenosis. Six-month angiographic and 1-year clinical follow-up was planned in all patients. A total of 199 patients with 213 lesions met eligibility criteria for enrollment. Short-term procedural success was achieved in 97.5%, with a major complication rate (death, emergency bypass surgery, or Q-wave myocardial infarction [MI]) of 2.5%. There were no early deaths. Non-Q-wave MI (CK-MB > 3 times normal) occurred in 14% of patients. Mean reference vessel diameter was 3.28 mm. Mean diameter stenosis was reduced from 63.5% to a final stenosis of 7%. Late 1-year clinical follow-up revealed one cardiac death and a target lesion revascularization rate of 17.8%. The angiographic restenosis rate at 6 months was 28.9%, with the major predictor of restenosis being a smaller postprocedure lumen diameter. CONCLUSIONS: Optimal DCA produced a low residual percent diameter stenosis and a lower restenosis rate than seen in previous trials without an increase in early or late major adverse events.

Aged↗
PubMed1998

Intravascular ultrasound predictors of angiographic restenosis in lesions treated with Palmaz-Schatz stents.

OBJECTIVES: This study sought to evaluate the clinical, procedural, preinterventional and postinterventional quantitative coronary angiographic (QCA) and intravascular ultrasound (IVUS) predictors of restenosis after Palmaz-Schatz stent placement. BACKGROUND: Although Palmaz-Schatz stent placement reduces restenosis compared with balloon angioplasty, in-stent restenosis remains a major clinical problem. METHODS: QCA and IVUS studies were performed before and after intervention (after stent placement and high pressure adjunct balloon angioplasty) in 382 lesions in 291 patients treated with 476 Palmaz-Schatz stents for whom follow-up QCA data were available 5.5 +/- 4.8 months (mean +/- SD) later. Univariate and multivariate predictors of QCA restenosis (> or = 50% diameter stenosis at follow-up, follow-up percent diameter stenosis [DS] and follow-up minimal lumen diameter [MLD]) were determined. RESULTS: Three variables were the most consistent predictors of the follow-up angiographic findings: ostial lesion location, IVUS preinterventional lesion site plaque burden (plaque/total arterial area) and IVUS assessment of final lumen dimensions (whether final lumen area or final MLD). All three variables predicted both the primary (binary restenosis) and secondary (follow-up MLD and follow-up DS) end points. In addition, a number of variables predicted one or more but not all the end points: 1) restenosis (IVUS preinterventional lumen and arterial area); 2) follow-up DS (QCA lesion length); and 3) follow-up MLD (QCA lesion length and preinterventional MLD and DS and IVUS preinterventional lumen and arterial area). CONCLUSIONS: Ostial lesion location and IVUS preinterventional plaque burden and postinterventional lumen dimensions were the most consistent predictors of angiographic in-stent restenosis.

Adult↗
PubMed1998

Remodeling after directional coronary atherectomy (with and without adjunct percutaneous transluminal coronary angioplasty): a serial angiographic and intravascular ultrasound analysis from the Optimal Atherectomy Restenosis Study.

OBJECTIVES: The intravascular ultrasound (IVUS) substudy of OARS (Optimal Atherectomy Restenosis Study) was designed to assess the mechanisms of restenosis after directional coronary atherectomy (DCA). BACKGROUND: Recent serial IVUS studies have indicated that late lumen loss after interventional procedures was determined primarily by the direction and magnitude of arterial remodeling, not by cellular proliferation. METHODS: Complete quantitative coronary angiography (QCA) and IVUS were obtained in 104 patients before and after intervention and during follow-up. All studies were performed after administration of 200 microg of intracoronary nitroglycerin. Angiographic measurements included minimum lumen diameter (MLD), interpolated reference diameter and diameter stenosis (DS). Intravascular ultrasound measurements included lesion and reference external elastic membrane (EEM), lumen and plaque+media cross-sectional area (CSA). The axial location of the lesion site was at the smallest follow-up lumen CSA; the reference segment was the most normal-looking cross section within 10 mm proximal to the lesion but distal to any major side branch. Results are reported as mean +/- one standard deviation. RESULTS: The QCA reference decreased from 3.51 +/- 0.46 mm to 3.22 +/- 0.44 mm; the MLD decreased from 3.22 +/- 0.47 mm to 2.03 +/- 0.72 mm; and the DS increased from 8 +/- 10% to 38 +/- 20%. On IVUS, the decrease in lumen CSA (from 8.8 +/- 2.5 mm2 to 5.5 +/- 4.0 mm2) was associated with a significant decrease in EEM (from 19.7 +/- 5.6 mm2 to 16.9 +/- 6.2 mm2); there was no significant increase in P+M (from 10.9 +/- 4.2 mm2 to 11.3 +/- 3.9 mm2). A change in lumen correlated with a change in EEM (r = 0.790, p < 0.0001), not with a change in P+M (r = 0.133, p = 0.2258). A decrease in reference EEM (from 19.1 +/- 7.7 mm2 to 17.6 +/- 8.0 mm2) also correlated with a decrease in lesion EEM (r = 0.665, p < 0.0001). Results in restenotic lesions were similar. CONCLUSION: Restenosis after optimal DCA is caused primarily by a decrease in EEM CSA that extends into contiguous reference segments.

Anatomy, Cross-Sectional↗
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

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

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

Influence of gender on in-hospital clinical and angiographic outcomes and on one-year follow-up in the New Approaches to Coronary Intervention (NACI) registry.

Higher complication rates and lower success rates for treatment of women compared with men have been reported in prior studies of coronary angioplasty and in most early reports of outcome with new coronary interventional devices. In multivariate analysis this has been attributed largely to older age and other unfavorable clinical characteristics. These results are reflected in the current guidelines for coronary angioplasty. Women in prior studies have also had different distributions of vessel and lesion characteristics, but the influence of these differences on the outcome of new-device interventions have not been adequately evaluated. This article evaluates the influence of gender on clinical and angiographic characteristics, interventional procedure and complications, angiographic success, and clinical outcomes at hospital discharge and 1-year follow-up, as observed in the New Approaches to Coronary Intervention (NACI) registry. The NACI registry methodology has been reported in detail elsewhere in this supplement. This study focuses on the 90% of patients-975 women and 1,880 men-who had planned procedures with a single new device and also had angiographic core laboratory readings. Women compared with men were older, had more recent onset of coronary ischemic pain that was more severe and unstable, and had more frequent histories of other adverse clinical conditions. The distributions of several but not all angiographic characteristics before intervention were considered more favorable to angioplasty outcome in women. Differences were observed in device use and procedure staging. Angiographically determined average gain in lumen diameter after new-device intervention, with or without balloon angioplasty, was significantly less in women (1.38 mm) than in men (1.53 mm; p < 0.001); this 0.15 mm difference is consistent with the 0.16-mm smaller reference vessel lumen diameter of women. However, final percent diameter stenoses and TIMI flow and lesion compliance characteristics were similar. Among procedural complications, only treatment for hypotension, blood transfusion, and vascular repair occurred more often in women. More women than men were clinically unstable (2.1% vs 1.1%) or went directly to emergent coronary artery bypass graft surgery (CABG; 1.2% vs 0.6%) on leaving the interventional laboratory. However, in-hospital death (1.4% vs 1.1%), Q-wave myocardial infarction (MI) (0.9% vs 1.1%), and emergent CABG (1.5% vs 1.0%, for women and men, respectively) were not significantly different. Nonemergent CABG was more frequent in women (1.8% vs 0.9%; p < 0.05) and length of hospital stay after device intervention was longer (4.4 days vs 3.8 days in men; p < 0.01). In both univariate and multivariate analyses gender did not emerge as a significant variable in relation to the combined endpoint, death, Q-wave MI, or emergent CABG at hospital discharge. At 1-year follow-up more women than men reported improvement in angina (70% vs 62%) and fewer women than men had had repeat revascularization (32% vs 36%). Similar proportions were alive and free of angina, Q-wave MI and repeat revascularization (46% of women vs 45% of men). Although several procedure-related complications were more frequent in women than men after coronary interventions with new devices, no important disadvantages were observed for women in the rates of major clinical events at hospital discharge and at 1-year clinical follow-up. Additional studies are needed to evaluate the complex interplay of clinical, vessel, and lesion characteristics on success and complications of specific interventional techniques and to determine whether gender, per se, is a risk factor and whether gender specific interventional strategies may be beneficial.

Aged↗
PubMed1997

Overestimation of acute lumen gain and late lumen loss by quantitative coronary angiography (compared with intravascular ultrasound) in stented lesions.

The accurate measurement of lumen dimensions is essential for guidance of interventional procedures and the assessment of acute and late results. This study compared intravascular ultrasound (IVUS) with quantitative coronary angiography (QCA) in the assessment of lumen dimensions before and after intervention, and at follow-up. Two hundred thirty-one consecutive patients treated with Palmaz-Schatz stents and evaluated using serial (before and after intervention, and follow-up) IVUS and QCA were screened. Because IVUS cannot measure dimensions smaller than the imaging catheter, patients having an angiographic minimal lumen diameter (MLD) less than the IVUS catheter (1.0 mm) during any study were excluded, leaving 71 patients in the final study group. IVUS and QCA measurements (reference dimensions and MLD) and calculations (percent diameter stenosis, acute lumen gain, late lumen loss, loss index, and restenosis rates) were compared. Correlation coefficients ranged from 0.641 to 0.816 for measured variables and from 0.280 to 0.680 for calculated variables. Reference lumen dimensions were consistently larger by IVUS than by QCA: 0.50 +/- 0.52 mm before intervention (p <0.0001), 0.46 +/- 0.45 mm after intervention (p <0.0001), and 0.38 +/- 0.53 mm at follow-up (p <0.0001). MLDs measured by IVUS were larger before intervention (0.17 +/- 0.28 mm, p <0.0001), smaller after intervention (0.17 +/- 0.34 mm, p <0.0001), and larger at follow-up (0.14 +/- 0.41 mm, p <0.0001). This resulted in a smaller acute gain and late loss measured by IVUS (0.33 +/- 0.39 and 0.30 +/- 0.47 mm, respectively, both p <0.0001). Although measures of restenosis (i.e., loss index and restenosis rates) were similar, the classification of lesions in individual patients (as restenotic vs nonrestenotic) was significantly different (p = 0.002, concordance rate = 73%). There are systematic differences between IVUS and QCA in the measurement of reference and lesion lumen dimensions. Although indexes of restenosis were similar, classification of lesions in individual patients was different.

Aged↗
PubMed1997

Treatment of in-stent restenosis with excimer laser coronary angioplasty: mechanisms and results compared with PTCA alone.

BACKGROUND: This study determined the clinical safety, mechanisms, and 6-month results of excimer laser angioplasty (ELCA)+adjunct PTCA for the treatment of in-stent restenosis and (via lesion matching) compared the results of ELCA+PTCA to PTCA alone. METHODS AND RESULTS: Using quantitative angiography (QCA) and intravascular ultrasound (IVUS), we studied 107 restenotic previously stented lesions in 98 patients before and after intervention. QCA measurements included minimum lumen diameter (MLD) and diameter stenosis (DS). IVUS measurements included stent, lumen, and intimal hyperplasia (IH=stent-lumen) cross-sectional areas (CSA) and volumes. In the 54 lesions treated with ELCA+PTCA, the MLD increased from 0.73+/-0.38 mm before ELCA to 2.10+/-0.47 mm after ELCA+PTCA (P<.0001); the DS decreased from 70+/-14% to 25+/-12% (P<.0001). By IVUS, the minimum lumen CSA increased from 1.58+/-0.78 mm2 before ELCA to 6.34+/-1.75 mm2 after ELCA+PTCA (P<.0001) as a result of an increase in minimum stent CSA from 7.70+/-2.41 to 9.10+/-2.60 mm2 (P<.0001) and a decrease in IH CSA from 5.25+/-2.84 to 2.63+/-1.41 mm2 (P<.0001). Volumetric analysis showed that tissue ablation (during ELCA) contributed 29+/-15%, tissue extrusion (during adjunct PTCA) contributed 31+/-14%, and additional stent expansion (during adjunct PTCA) contributed 40+/-16% to the overall lumen gain. There were no ELCA-related complications. Matched to lesions treated with PTCA alone, ELCA+PTCA resulted in greater lumen gain, more IH ablation/extrusion, larger final lumen CSA (IVUS), and a tendency for less frequent need for subsequent target vessel revascularization (TVR, 21% versus 38%, P=.0823). CONCLUSIONS: ELCA safely and effectively ablates in-stent neointimal tissue. Adjunct PTCA extrudes neointimal tissue out of the stent and also further expands the stent. Compared with PTCA alone, ELCA+PTCA achieves better short-term and, potentially, better long-term results.

Angioplasty, Balloon, Coronary↗
PubMed1997

Comparison of men versus women in cross-sectional area luminal narrowing, quantity of plaque, presence of calcium in plaque, and lumen location in coronary arteries by intravascular ultrasound in patients with stable angina pectoris.

Women have an increased mortality after coronary interventions compared with men, which may be partly explained by differences in comorbid clinical conditions. However, whether women also have quantitative differences in coronary atherosclerosis is not known. Preinterventional intravascular ultrasound (IVUS) was used to study de novo, nonostial native coronary lesions in 169 women and 549 men with chronic angina. The external elastic membrane (EEM), lumen, and plaque + media (P + M) areas, plaque burden, plaque eccentricity, and calcium were measured at the target lesion and at a proximal reference site. All cross-sectional IVUS measures were also corrected for body surface area. Results are reported as mean +/- 1 SD. Women had significantly smaller reference site EEM (16.5 +/- 5.3 vs 19.4 +/- 6.3 mm2, p <0.0001), lumen (8.7 +/- 3.0 vs 9.9 +/- 4.0 mm2, p = 0.0020), and P + M areas (7.8 +/- 3.7 vs 9.5 +/- 4.2 mm2, p = 0.0001). Women also had significantly smaller lesion site EEM (16.2 +/- 5.9 vs 18.3 +/- 6.7 mm2, p = 0.0028), lumen (2.4 +/- 1.7 vs 2.9 +/- 2.6 mm2, p = 0.0273), and P + M areas (13.6 +/- 5.7 vs 15.3 +/- 6.4 mm2, p = 0.0112). However, when corrected for BSA, these differences were no longer significant. Women and men also had similar reference and lesion plaque burden, eccentricity, and calcium. Preinterventional IVUS analysis failed to detect any quantitative or qualitative differences in coronary atherosclerosis in men compared with women.

Aged↗