The influence of diabetes mellitus on plaque volume and vessel size in patients undergoing percutaneous coronary intervention

We evaluated the influence of diabetes on plaque volume and vessel size at a reference segment in diabetic patients undergoing percutaneous coronary intervention using both angiograms and quantitative intravascular ultrasound. A total of 344 patients with 449 de novo coronary lesions including 97 diabetics (133 lesions) who underwent elective percutaneous coronary intervention under intravascular ultrasound guidance were included in this study. Eleven diabetic patients (19 lesions) received insulin and 52 patients (77 lesions) oral hypoglycemic drugs. The other 34 patients (37 lesions) received diet/exercise therapy alone. We measured vessel area (VA) and lumen area (LA) at proximal and distal reference segments by intravascular ultrasound, which were averaged. Plaque area (VA-LA) and % plaque area (100 x plaque area/VA) were subsequently calculated. Although VA was similar between diabetic and non-diabetic patients (13.46 +/- 4.49 mm2 in diabetics versus 14.11 +/- 5.24 mm2 in non-diabetics, P = 0.214), LA was smaller (6.51 +/- 2.63 mm2 versus 7.38 +/- 3.08 mm2, P = 0.004) and % PA was larger (50.4 +/- 11.7 versus 46.5 +/- 11.3, P < 0.001) in diabetic patients, especially the group receiving a hypoglycemic drug or insulin. VA, LA, and % PA were similar between patients with and without insulin treatment. These results potentially might cause undersized device selection without intravascular ultrasound guidance.     

Intravascular ultrasound predictors of subacute vessel closure after balloon angioplasty or atherectomy

BACKGROUND: Factors leading to subacute vessel closure after percutaneous coronary intervention (PCI) have not been well established in lesions treated with balloon angioplasty or atherectomy. METHODS AND RESULTS: We used intravascular ultrasound (IVUS) to determine the pre- and post-PCI characteristics involved in subacute vessel closure after PCI. Of 3,403 patients undergoing IVUS imaging during coronary balloon angioplasty or atherectomy, 8 patients (0.2%) developed angiographically documented subacute vessel closure within 1 week post-PCI and were compared to a group matched by procedure date (within 6 months), age, gender, stable or unstable angina, lesion location and treatment (balloon angioplasty or atherectomy). IVUS identified at least one cause for subacute vessel closure in 87% of patients (vs 25% in matched lesions, p < 0.01). Causes were all procedure-related and included inadequate final lumen (60%), dissection (50%) and thrombus (25%). Pre-procedure lesion characteristics were not different from matched lesions. CONCLUSIONS: Subacute vessel closure after balloon angioplasty or atherectomy is mostly related to insufficient post-procedure lumen dimension or dissection.     

Coronary remodeling of proximal and distal stenotic atherosclerotic plaques within the same artery by intravascular ultrasound study

The aim of this intravascular ultrasound study was to compare the type and the degree of vessel remodeling in proximal and distal de novo lesions within the same coronary artery in patients with stable angina pectoris. Seventy-six de novo coronary artery lesions in 38 coronary arteries of 38 patients were imaged by intravascular ultrasound. The vessel area (VA) within the external elastic lamina and the lumen area (LA) were measured, and the wall area (VA-LA) was calculated at the lesion site, and the proximal and distal reference sites. The VA ratio was defined as (lesion VA/average of the proximal and distal reference VAs) to represent the degree of vessel remodeling. The proximal coronary segments showed compensatory enlargement more often (68% vs 29%, p < 0.01) than the distal segments, and the VA ratio at the lesion site was significantly larger (1.1 +/- 0.3 vs 1.0 +/- 0.2, p <0 .01) in proximal segments than in distal segments. The type of coronary remodeling was discordant in 61% and concordant in only 39% of coronary arteries between the proximal and distal segments. The type of coronary remodeling of proximal and distal coronary lesions was inhomogeneous, even within the same vessel. Proximal coronary segments showed more prominent compensatory enlargement than distal segments, which have a similar degree of luminal narrowings.     

Effect of coronary risk factors on arterial compensatory enlargement in japanese middle-aged patients with de novo single-vessel disease--an intravascular ultrasound study

BACKGROUND: Compensatory enlargement (CE) of atherosclerotic human arteries has been reported; however, the pattern of arterial remodeling in response to plaque formation is not unique. HYPOTHESIS: The study was undertaken to determine the extent of coronary artery compensatory enlargement at stenotic lesions and to correlate the arterial compensatory enlargement with risk factors. METHODS: We studied 62 patients with stable angina and de novo single-vessel disease using intravascular ultrasound and obtained good images in 42 patients (68%). The vessel cross-sectional area (VA), lumen cross-sectional area (LA), and plaque cross-sectional area (PA) were measured at the lesion site and at proximal and distal reference sites. Positive CE was defined as increase in VA of lesion site > 10% compared with that of proximal reference site (CE group, n = 15); shrinkage was defined as reduction in VA of lesion site > 10% compared with that of proximal reference site (S group, n = 14); inadequate CE was defined as intermediate between CE and S (IE group, n = 13). All subjects had coronary risk factors measured before this study. RESULTS: There was no difference in VA, LA, or PA among the three groups at the proximal and distal reference sites, nor in LA at the lesion site; however, VA and PA were significantly smaller in the S group than in the other groups (p < 0.01). Of coronary risk factors, increased systolic blood pressure (SBP), increased diastolic blood pressure (DBP), and decreased high-density lipoprotein cholesterol (HDL-c) levels had the strongest association with shrinkage (p < 0.05). CONCLUSION: Hypertension and decreased HDL level may contribute to the shrinkage response in middle-aged patients with stable angina.     

The influence of plaque orientation (pericardial or myocardial) on coronary arterial remodeling

BACKGROUND: Many systemic, regional and lesion factors have been identified which may influence arterial remodeling, but little is known about the importance of extravascular resistance to vessel enlargement. As myocardial systolic splinting may significantly affect vessel expansion the effect of plaque orientation on arterial remodeling in eccentric coronary atherosclerotic lesions was examined. METHODS: Using intravascular ultrasound imaging to obtain cross-sectional vessel area (VA), plaque area (PA) and lumen area (LA), remodeling in eccentric left anterior descending coronary artery lesions was compared which predominantly involved the pericardial or free arc (P, n=25) and the myocardial side (M, n=40) of the vessel wall. Normalized vessel area (NVA, VA(lesion)/VA(reference)) was compared as a continuous and categorical variable (positive>1.05, intermediate 0.95-1.05, negative<0.95) as well as remodeling index (RI, VA(lesion)-VA(reference)/PA(lesion)-PA(reference)). RESULTS: The two groups were well matched for clinical and lesion characteristics known to affect remodeling. Reference segments areas were similar in the two groups; while lesion LA was also similar, in the pericardial group there was significantly greater lesion PA (P 12.78+/-0.72, M 10.26+/-0.50 mm(2), P<0.05) and VA (P 15.71+/-0.90, M 12.82+/-0.57 mm(2), P<0.05) demonstrating enhanced compensatory remodeling. Outward remodeling was significantly greater in P than in M by both NVA (P 1.03+/-0.03, M 0.86+/-0.03, P<0.01) and RI (P 0.02+/-0.07, M -1.10+/-0.32, P<0.01). Positive, intermediate and negative remodeling occurred in nine, nine and seven lesions in P and in four, ten and 26 lesions in M (P<0.01). CONCLUSIONS: Remodeling compensates more for plaque growth in eccentric coronary lesions which are surrounded by the pericardium than those surrounded by the myocardium. Extravascular resistance appears to influence arterial remodeling.     

Impact of deep vessel wall injury and vessel stretching on subsequent arterial remodeling after balloon angioplasty: a serial intravascular ultrasound study

Background Arterial remodeling has been shown to be responsible for lumen narrowing after nonstent interventions. Methods To examine the impact of deep vessel wall injury (DI) after balloon angioplasty on the subsequent vessel remodeling process, we performed serial intravascular ultrasound (IVUS) analysis in 47 native coronary artery lesions that underwent balloon angioplasty. An IVUS study was performed before and after balloon angioplasty and repeated at follow-up. Vessel and lumen area were measured at the narrowest site before intervention. Plaque area was calculated as vessel area minus lumen area. DI was defined as the presence of plaque/vessel wall fracture deep in the medial layer (sonolucent zone by IVUS) after angioplasty. Results After angioplasty, DI was present in 18 (38%, DI group) and absent in 29 (62%, non-DI group) of lesions. During follow-up, changes in vessel area in the DI group were significantly larger than in the non-DI group (P = .007). There were no significant differences in changes in plaque area. A trend toward greater late lumen loss was observed in the non-DI group (P = .05). In the DI group, changes in lumen area correlated better with changes in vessel area (r = 0.81, P < .0001) than with changes in plaque area (r = 0.32, P = .20). However, in the non-DI group, changes in lumen area correlated with changes in plaque area (r = −0.55, P = .002), but not with changes in vessel area (r = 0.30, P = .11). Conclusions Deep vessel wall injury after balloon angioplasty is associated with the magnitude of the subsequent vessel remodeling process. The differences in the remodeling process may have implications regarding adjunctive therapies to prevent restenosis after balloon angioplasty. (Am Heart J 2002;144:323-8.)     

Impact of diabetes mellitus on angiographically silent coronary atherosclerosis.

Constrictive remodeling occurs in significant atherosclerotic lesions of the diabetic patient, but the impact of diabetes mellitus (DM) on the angiographically normal coronary artery is still unclear. Morphometric analysis using intravascular ultrasound (IVUS) prior to intervention evaluated 54 sites in 33 DM patients and 106 in 62 non-diabetic patients. Vessel area (VA) and lumen area (LA) were measured at angiographically normal sites in the vessel. Plaque area (PA) was calculated as VA - LA. Percentage plaque area (%PA) was calculated as PA VA. Even in the angiographically normal site, mild coronary atherosclerosis was detected by IVUS in both groups. In the patients with DM, VA and LA were significantly smaller than in the non-diabetic patient (15.5 vs 17.8 mm(2), p<0.01; and 10.1 vs 12.2 mm(2), p<0.01 respectively), whereas % PA was similar (34.5 vs 31.6%). At angiographically normal sites where mild coronary atherosclerosis is detected by IVUS, the coronary artery of diabetic patients is smaller than that of the non-diabetic. These results suggest impaired compensatory enlargement or some other constrictive mechanism has already occurred in the early stages of coronary atherosclerosis in patients with DM.     

Comparison of cutting balloon vs stenting alone in small branch ostial lesions of native coronary arteries.

Angioplasty of small vessels is associated with a higher rate of restenosis, even in the ostium. The present study compared the acute, late results of cutting balloon vs those of stenting alone in small branch ostial lesions of native coronary arteries and the effect on the parent vessel. The study group comprised 61 patients with successful angioplasty of smaller branch ostial lesions in native coronary arteries. The reference vessel diameter was between 2.5 and 3.0 mm. Patients were divided into 2 groups: group I (cutting balloon, n=30) and group II (stenting alone, n=31). After intervention, patients in group II achieved significant acute lumen gain, larger minimal lumen diameter (MLD) and less diameter stenosis. At 3-month follow-up, the MLD and diameter stenosis of the 2 groups were almost identical; however, late loss was lower in group I. At the 6-month follow up, the cumulative restenosis rate was 41% (11/27) in group I compared with 63% (19/31) in group II (p=0.05), and the target lesion revascularization was also lower in the cutting balloon group [29% (8/27) vs 53% (16/30) p=0.05]. In group 1, the MLD of the parent vessel did not change before, after cutting balloon or at follow-up. In contrast, there were significant reductions in parent vessel MLD following stenting alone and at follow-up. Plaque shift did not occur in the cutting balloon group. Cutting balloon angioplasty is a feasible approach for the treatment of small branch ostial lesions and does not cause significant narrowing of the parent vessel.     

Preintervention lesion remodelling affects operative mechanisms of balloon optimised directional coronary atherectomy procedures: a volumetric study with three dimensional intravascular ultrasound

AIMS: To classify atherosclerotic coronary lesions on the basis of adequate or inadequate compensatory vascular enlargement, and to examine changes in lumen, plaque, and vessel volumes during balloon optimised directional coronary atherectomy procedures in relation to the state of adaptive remodelling before the intervention. DESIGN: 29 lesion segments in 29 patients were examined with intravascular ultrasound before and after successful balloon optimised directional coronary atherectomy procedures, and a validated volumetric intravascular ultrasound analysis was performed off-line to assess the atherosclerotic lesion remodelling and changes in plaque and vessel volumes that occurred during the intervention. Based on the intravascular ultrasound data, lesions were classified according to whether there was inadequate (group I) or adequate (group II) compensatory enlargement. RESULTS: There was no significant difference in patient and lesion characteristics between groups I and II (n = 10 and 19), including lesion length and details of the intervention. Quantitative coronary angiographic data were similar for both groups. However, plaque and vessel volumes were significantly smaller in group I than in II. In group I, 9 (4)% (mean (SD)) of the plaque volume was ablated, while in group II 16 (11)% was ablated (p = 0.01). This difference was reflected in a lower lumen volume gain in group I than in group II (46 (18) mm(3) v 80 (49) mm(3) (p < 0.02)). CONCLUSIONS: Preintervention lesion remodelling has an impact on the operative mechanisms of balloon optimised directional coronary atherectomy procedures. Plaque ablation was found to be particularly low in lesions with inadequate compensatory vascular enlargement.     

Impact of pre-interventional arterial remodeling on subsequent vessel behavior after balloon angioplasty: a serial intravascular ultrasound study

OBJECTIVES

The purpose of this study was to assess the impact of pre-intervention arterial remodeling on subsequent vessel behavior following balloon angioplasty.

BACKGROUND

Positive arterial remodeling before intervention has been shown to have a negative impact on the clinical outcome after nonstented coronary interventional procedures. However, the mechanism of interventions in coronary vessel geometry over time is less well characterized.

METHODS

Serial (pre-, post- and follow-up) intravascular ultrasound analysis was performed in 46 native coronary lesions. Positive remodeling (PR) was defined as vessel area (VA) at the target lesion greater than that of average reference segments. Intermediate or negative remodeling (IR/NR) was defined as VA at the target lesion less than or equal to that of average reference segment. Remodeling index was defined as VA at the target lesion site divided by that of average references.

RESULTS

Pre-interventional PR and IR/NR were present in 21 (46%) and 25 (54%) of 46 patients, respectively. At follow-up, the change in plaque area was similar between the two groups (1.3 ± 2.1 vs. 1.2 ± 2.1 mm², P = 0.840). Lesions with PR showed a significantly smaller change in VA than those with IR/NR (−0.2 ± 2.5 vs. 1.4 ± 2.3 mm², P = 0.03). As a result, late lumen loss was significantly larger in lesions whose pre-intervention configuration exhibited PR (−1.5 ± 1.8 vs. 0.2 ± 1.6 mm², P = 0.002).

CONCLUSIONS

Lesions with PR appear to have less capacity to compensate for further plaque growth after balloon angioplasty and thus show a proportional increase in late lumen loss. This may in part explain the less favorable clinical outcomes of positively remodeled lesions.     

Intravascular ultrasound-guided percutaneous transluminal coronary angioplasty with provisional spot stenting for treatment of long coronary lesions.

OBJECTIVES: The purpose of this study was to evaluate the approach of intravascular ultrasound (IVUS)-guided percutaneous transluminal coronary angioplasty (PTCA) with spot stenting (SS) for the treatment of long coronary lesions. BACKGROUND: Treating long coronary lesions with balloon angioplasty results in suboptimal short- and long-term outcomes. Full lesion coverage with traditional stenting (TS) has been associated with a high restenosis rate. METHODS: We prospectively evaluated a consecutive series of 130 long lesions (>15 mm) in 101 patients treated with IVUS-guided PTCA and SS. The results were compared with those of TS in a matched group of patients. Coronary angioplasty was performed with a balloon to vessel ratio of 1:1, according to the IVUS media-to-media diameter of the vessel at the lesion site, to achieve prespecified IVUS criteria: lumen cross-sectional area (CSA) > or =5.5 mm(2) or > or =50% of the vessel CSA at the lesion site. The stents were implanted only in the vessel segment where the criteria were not met. RESULTS: In the SS group, stents were implanted in 67 of 130 lesions, and the mean stent length was shorter than that of lesions in the matched TS group (10.4 +/- 13 mm vs. 32.4 +/- 13 mm, p < 0.005). The 30-day major adverse cardiac event (MACE) rate was similar (5%) for both groups. Angiographic restenosis was 25% with IVUS-guided SS, as compared with 39% in the TS group (p < 0.05). Follow-up MACE and target lesion revascularization rates were lower in the SS group than in the TS group (22% vs. 38% [p < 0.05] and 19% vs. 34% [p < 0.05], respectively). CONCLUSIONS: Intravascular ultrasound-guided SS for the treatment of long coronary lesions is associated with good acute outcome. Angiographic restenosis and follow-up MACE rates were significantly lower than those with TS.     

Coronary artery distensibility and compensatory vessel enlargement--a novel parameter influencing vascular remodeling?

Vascular remodeling implies the concept of compensatory vessel enlargement to preserve luminal dimensions during atheromatous plaque development. However, negative remodeling, i.e. vessel shrinkage in response to plaque accumulation has also been described. So far, the factors influencing positive or negative remodeling are uncertain. We hypothesized that vascular distensibility, a measure of vessel compliance, is related to compensatory enlargement. In 58 patients undergoing intravascular ultrasound interrogation of a de novo lesion prior to coronary intervention, the cross-sectional vessel area (VA), lumen area (LA) and plaque area (PA = VA minus LA) were measured at end diastole and end systole at the lesion site and at the proximal and distal reference segments. Positive remodeling was defined to be present when the VA at the lesion was > 1.05 times larger than that at the proximal reference (group A), negative remodeling when the VA at the lesion was < 0.95 of the reference site (group C) and in-between was considered to be intermediate (group B). Vessel compliance was measured by calculating vascular distensibility. Results showed a similar LA at the lesion site in all groups (4.18 ± 2.18 vs. 4.36 ± 1.19 vs. 3.74 ± 1.81 mm², NS) while VA and PA were significantly larger in group A (17.19 ± 5.08 vs. 14.22 ± 3.66 and 12.45 ± 4.82 mm², p = 0.005 and 13 ± 4.55 vs. 9.95 ± 3.58 and 8.7 ± 3.83, p = 0.003, respectively). Vascular distensibility at the proximal reference segment was significantly greater in group A (3.55 ± 2.67 vs. 1.25 ± 1.03 and 0.85 ± 0.73 mmHg⁻¹, p < 0.001) with a positive correlation between remodeling and distensibility (R = 0.52, p < 0.001). In a multiple regression model including clinical and lesional factors, distensibility was the only predictor of remodeling. In conclusion, these results suggest that compensatory vessel enlargement occurs to a greater degree in patients with increased coronary artery distensibility, which appears to be a predictor for positive remodeling. Received: 14 September 2000, Returned for revision: 30 October 2000, Revision received: 8 January 2001, Accepted: 24 January 2001     

Effects of radial stretch on target lesion revascularization after percutaneous coronary intervention: an intravascular ultrasound study

OBJECTIVE: To analyze possible associations between radial stretch during coronary angioplasty and the incidence of target lesion revascularization (TLR). PATIENTS AND METHODS: Intravascular ultrasound images were obtained before and after revascularization in 182 native coronary lesions. The quantitative intravascular ultrasound parameters (external elastic membrane cross-sectional area [EEM-A], lumen areas [LA], plaque area [PA], calculated as EEM-A-LA, and changes between pre- and postinterventional LA [DLA], EEM-A [DEEM-A] and PA [DPA]) were correlated with the incidence of TLR. RESULTS: TLR was performed in 60 (33%) patients, while 122 (67%) patients remained event free. Postinterventional PA remained significantly larger in the TLR group than in the event-free group (9.2 +/- 3.3 mm2 versus 7.9 +/- 3.3 mm2; P=0.02). The radial stretch during intervention, expressed as DEEM-A, and the balloon to artery ratio was significantly larger in the TLR group (DEEM-A: 1.9 +/- 2.1 mm2 versus 1.3 +/- 2.0 mm2; P=0.03; balloon to artery ratio: 1.3 +/- 0.2 versus 1.0 +/- 0.5; P=0.04). Multivariate analysis revealed DEEM-A (P=0.01), DPA (P=0.03), diabetes (P=0.001, odds ratio 5.2, 95% CI 4.9 to 6.5) and adaptive remodelling (P<0.001, odds ratio 4.1, 95% CI 3.5 to 6.4) as independent predictors for TLR. CONCLUSION: Whereas patients in whom lumen gain is achieved primarily by plaque reduction with less wall stretch tend to remain event free, patients with significant radial stretch (ie, less reduction of the PA, but a radial outward shift of the plaque mass) experience a higher incidence of TLR.     

切割球囊血管成型术对C-反应蛋白白细胞介素-6及细胞间粘附分子的影响

目的 :比较切割球囊预扩张与普通球囊预扩张后支架置入术对C 反应蛋白 (CRP)、白细胞介素 6 (IL 6 )及可溶性细胞间粘附分子 1(sICAM 1)的影响。方法 :将冠状动脉造影显示单纯前降支近端病变的不稳定型心绞痛患者分为 2组 ,一组给予普通球囊预扩张后支架置入 ,另一组给予切割球囊预扩张后支架置入 ,并分别在术前、术后 1、6、2 4、4 8h测定C 反应蛋白、白细胞介素 6及可溶性细胞间粘附分子的浓度。结果 :2组患者一般情况、病变情况无显著统计学差异 ,术后 6hC 反应蛋白、白细胞介素 6较术前升高 ,2 4h达高峰 ;可溶性细胞间粘附分子术后 1h较术前升高 ,术后 6h达高峰。切割球囊组C 反应蛋白、白细胞介素 6水平在术后 6、2 4、4 8h均显著低于普通球囊组 ,可溶性细胞间粘附分子水平在术后 1、6、2 4、4 8h低于普通球囊组。介入治疗中切割球囊组球囊最大充盈压 (MIP)明显低于普通球囊组。结论 :切割球囊血管成型术对C 反应蛋白、白细胞介素 6及可溶性细胞间粘附分子的影响小于普通球囊组 ,可能是切割球囊降低术后再狭窄的机制之一     

切割球囊临床应用的有效性和安全性评价

目的 探讨切割球囊临床应用的安全性和有效性。方法 对131例患者142处狭窄病变进行切割球囊或切割球囊＋支架治疗。结果 142处狭窄病变行切割球囊治疗中4次失败，成功率为97.2%。切割球囊治疗支架内再狭窄、开口部病变、分叉病变和小血管弥漫性病变以及其他类型病变各为69处、16处、19处、7处和27处，7例切割球囊扩张后发生内膜撕裂，均为A型夹层，发生率为5.3%，术中无死亡和急性心肌梗死及其他严重血管并发症发生。失败原因与病变严重钙化以及切割球囊不能达到或通过狭窄部位有关。结论 切割球囊临床应用是安全面有效的。     

Contribution of localized calcium deposits to dissection after angioplasty. An observational study using intravascular ultrasound.

BACKGROUND. Atherosclerotic plaque fracture and dissection of the arterial wall are frequent concomitants of the balloon angioplasty process. The composition and morphology of plaque within the vessel may be critical in determining the extent of plaque fracture and dissection during balloon angioplasty. To examine this potential association in the clinical setting, we studied patients with intravascular ultrasound imaging after balloon angioplasty. METHODS AND RESULTS. Forty-one patients were studied with intravascular ultrasound after angioplasty in both peripheral and coronary arteries. Ultrasound images representing the target lesion cross section were digitized, stored on computer, and analyzed off-line. The presence of intralesional calcium and the relative size of dissection for each lesion was computed. Thirty-one patients (76%) had ultrasound evidence of significant dissection or plaque fracture immediately after balloon dilation. In 23 of 31 (74%) of the lesions, the ultrasound scans showed significant localized calcium deposits within the plaque substance. In 87% of these cases, the dissections were adjacent to the calcific portion of the vessel wall. In addition, the relative size of dissections referenced to the neolumen area were significantly larger (p less than or equal to 0.002) in the calcified vessels (27.5 +/- 12.3%) compared with the size of the dissections in lesions without calcium (11.2 +/- 5.8%). CONCLUSIONS. The presence of calcium within the vessel wall appeared to be significantly associated with both the location and size of the dissected tissue arm from the vessel wall. These data suggest that localized calcium deposits have a direct role in promoting dissection, presumably by increasing shear stresses within the plaque.     

Greater late lumen loss after successful coronary balloon angioplasty in the proximal left anterior descending coronary artery is not explained by extent of vessel wall damage or plaque burden

OBJECTIVES: We investigated whether the greater late lumen loss after coronary balloon angioplasty in the proximal left anterior descending artery (P-LAD) compared with that in other segments might be related to differences in vascular dimensions or morphology as determined by angiography and intravascular ultrasound imaging. BACKGROUND: The greater late lumen loss after angioplasty in the P-LAD that has been observed in several studies has not been explained. METHODS: We studied 178 patients and 194 coronary artery lesions by quantitative angiography and 30 MHz intravascular ultrasound imaging after successful balloon angioplasty. Vessel wall morphology was compared among three proximal and three nonproximal segments. Follow-up quantitative angiography for late lumen loss calculation was performed in 168 lesions. Multivariate analysis was used to determine predictors of late lumen loss. RESULTS: Absolute and relative late loss were significantly greater at the P-LAD compared with the pooled group of other segments (0.42 +/- 0.60 mm vs. 0.10 +/- 0.48 mm, p = 0.0008 and 0.14 +/- 0.24 vs. 0.03 +/- 0.17, p < 0.001). Also, a greater percentage of calcific lesions (65% vs. 44%, p = 0.034), a lower incidence of rupture (51% vs. 74%, p = 0.009) and a larger reference segment plaque area (5.4 +/- 2.2 mm2 vs. 4.7 +/- 1.9 mm2, p = 0.05) were found in the P-LAD. In multivariate analysis however, these variables were not predictive of late loss. CONCLUSIONS: Greater late lumen loss after coronary balloon angioplasty of the P-LAD is not explained by differences in atherosclerotic plaque burden or in vessel wall damage.     

Mechanism of lumen gain during coronary stent deployment in diabetic patients compared with non-diabetic patients

BACKGROUND: Diabetic patients show an increased incidence of restenosis after coronary angioplasty than non-diabetic patients. This may be because of differences in the mechanism of lumen gain during coronary revascularization in this population cohort. DESIGN: This study analyses the mechanism of lumen gain during coronary stent deployment in diabetic patients compared with non-diabetic patients with intravascular ultrasound (IVUS). METHODS: IVUS images were obtained prior to and after revascularization in 26 diabetic and 97 non-diabetic patients. The external elastic membrane cross-sectional area (EEM) and lumen cross-sectional area (LA) were measured. Plaque area (PA) was calculated as EEM minus LA. Differences between pre- and post-LA (deltaLA), EEM (deltaEEM) and PA (deltaPA) were calculated. RESULTS: Pre-interventional PA (diabetic patients: 12.4 +/- 4.4 mm2 compared with non-diabetic patients: 10.7 +/- 3.6 mm2, = 0.04) and pre-interventional EEM (15.5 +/- 4.4 mm2 compared with 13.6 +/- 3.7 mm2 respectively, P = 0.02) were larger in the diabetic group. Postinterventional PA (10.2 +/- 3.2 mm2 compared with 8.0 +/- 3.4 mm2, P = 0.004) was also larger and postinterventional LA (6.3 +/- 2.2 mm2 compared with 7.4 +/- 2.4 mm2 = 0.04), deltaEEM (0.9 +/- 1.8 mm2 compared with 1.8 +/- 1.8 mm2 P = 0.04) and deltaLA (3.1 +/- 1.6 mm2 compared with 4.2 +/- 2.2 mm2, P = 0.03) were smaller in the diabetic group. The diabetic group exhibited longer lesion lengths (P = 0.04) and a higher inflation pressure was used during revascularization in this patient cohort (P = 0.02). CONCLUSION: Diabetic patients have less reduction of PA during revascularization and because the vessel wall cannot be stretched outwards despite higher inflation pressure, postinterventional LA remains smaller than in the non-diabetic population cohort. This might be a rudiment for consideration of different treatment strategies such as cutting balloon or atherectomy prior to stenting in this population group in order to achieve better procedural outcome.     

Update on Cutting Balloon Angioplasty

Cutting balloon (CB) is a unique balloon catheter with 3 or 4 metal blades on its surface making controlled endovascular surgical incisions that show promise of causing less vessel wall injury and less intimai proliferation. Multicenter randomized trials have revealed that CB angioplasty with multiple inflations achieved better lumen enlargement than single inflation and reduced coronary dissection more than plain old balloon angioplasty (POBA). Follow-up results showed CB angioplasty had a smaller late loss and loss index, resulting in lessened restenosis and target lesion revascularization rates. The main indication of CB angioplasty is basically a noncalcified lesion with concentric plaque; however, it could be applied effectively to some lesions unsuitable for POBA including in-stent restenosis, small vessel, long diffuse lesion, or ostial lesion. Additional evaluation would be necessary to determine the role of CB angioplasty in the stent era.     

Pressure wire guide provisional coronary stent implantation

OBJECTIVES: Whether coronary artery lesion successfully dilated by balloon angioplasty should be stented or not is unclear. The purpose of this study is to evaluate the provisional stent implantation method assessing residual ischemia by pressure wire. METHODS: Thirty-one patients with de-novo lesions suitable for stenting were enrolled in a pressure wire guided provisional stent study. The pressure wire was used to assess the fractional flow reserve(FFR) before and after balloon angioplasty. When the FFR after angioplasty was less than 0.75, stent implantation was planned. Patients with lesions consisting of an intermediate stenosis proximal to the target lesion, chronic total occlusion, bypass graft and left main lesion were excluded from the study. Stent implantation was permitted even if the FFR was more than 0.75 when the operator thought stenting was necessary. Medical treatment was given with aspirin 162 mg/day, cilostazol 200 mg/day for 6 months and additional ticlopidine 200 mg/day for a month after stenting the lesion. RESULTS: Target vessel was the left anterior descending coronary artery in 19 lesions, the right coronary artery in 3, and the circumflex coronary artery in 9. Stent implantation was performed in seven (23%) of 31 lesions and the other 24(77%) lesions were treated with only balloon angioplasty. The FFR before intervention was 0.58 +/- 0.16, and improved to 0.87 +/- 0.07 (p < 0.0001). Percentage diameter stenosis before intervention was 70.7 +/- 12.6% and improved to 20.1 +/- 13.3% (p < 0.0001) after intervention. There was no major cardiac event (death, coronary artery bypass grafting, myocardial infarction, stent thrombosis). Six months follow-up angiography was performed in 27 patients (87%). Angiographic restenosis (percentage diameter stenosis > or = 50%) was found in four patients (15%). A new lesion was found in two patients. Target vessel revascularization was performed in six patients (21%). CONCLUSIONS: Lesions successfully dilated by balloon angioplasty with FFR > or = 0.75 do not require stenting.