Angiographic patterns of restenosis after percutaneous intervention of chronic total occlusive lesions with drug-eluting stents.

BACKGROUND: Although the success rate of percutaneous coronary intervention (PCI) of chronic total occlusive (CTO) lesions is rising recently, the nature and behavior of these revascularized lesions in the real-world practice are unknown. METHODS: Data was collected from a prospective cohort of patients with successfully revascularized CTO lesions using drug-eluting stent (DES). Among these, patients with angiographical in-stent restenosis (ISR) were analyzed. RESULTS: 58% (n=149) of the total patients (n=255) with successful PCI of CTO received 6-9 months' angiographical follow-up. Angiographic ISR was identified in 36 lesions from 36 patients. There was a strong tendency towards diffuse ISR (61% of total ISR lesions) in these lesions, as compared with ISR after implantation of DES for non-CTO lesion in previous literatures. Multivariate analysis showed that post-procedural minimal lumen diameter (MLD) and total stent length were the only reliable predictors of diffuse ISR (HR 0.527 per 0.5 mm increment of MLD, HR 1.262 per 10mm increment of stent length). Compared with the group with larger post-procedural MLD (> 1.9 mm) and shorter stent length (≤ 55 mm), the group with smaller post-procedural MLD (≤ 1.9 mm) and longer stent length (> 55 mm) carried a 9-fold higher risk of diffuse restenosis. In addition, diffuse ISR was more frequently associated with symptoms or signs of myocardial ischemia. CONCLUSION: Revascularized CTO lesions using DES may carry a high risk of diffuse ISR, which is associated with more frequent myocardial ischemia compared with focal ISR. Post-procedural MLD and total stent length are significant predictors of these types of ISR after successful CTO intervention.

Significance of noncalcified coronary plaque in asymptomatic subjects with low coronary artery calcium score: assessment with coronary computed tomography angiography.

We aimed to investigate the prevalence and severity of noncalcified coronary plaques (NCP) using coronary CT angiography (CCTA) and analyze predictors of significant coronary stenosis by NCP in asymptomatic subjects with low coronary artery calcium score (CACS). The institutional review board approved this retrospective study and all patients gave written, informed consent. The presence of plaque, severity of stenosis, plaque characteristics, and CACS were assessed in 7,515 asymptomatic subjects. We evaluated the prevalence and severity of NCP in subjects having low CACS (707 subjects; men with CACS from 1 to 50 and women from 1 to 10) in comparison to those having 0 CACS (6,040 subjects) as the reference standard. Conventional risk factors were assessed for predictors of NCP and significant stenosis by NCP. We also investigated the cardiac events of the patients through medical records. Compared to subjects with 0 CACS, those with low CACS showed higher prevalence of NCP (6.9% vs. 31.5%, P < 0.001) and significant stenosis caused by NCP (0.8% vs. 7.5%, P < 0.001). In the low CACS group, independent predictors for significant NCP included diabetes mellitus (DM), hypertension, and elevated low-density lipoprotein (LDL)-cholesterol (all P < 0.05). However, 47.2% of subjects with significant NCP were classified into the low to intermediate risk according to Framingham Risk Score. At the median follow up of 42 months (range: 3-60 months), cardiac events were significantly higher in the low CACS group compared to the 0 CACS group (2.6% vs. 0.27%, P < 0.001). In asymptomatic subjects having low CACS, the prevalence and severity of NCP were higher as compared to subjects having zero CACS and predictors of significant stenosis by NCP were DM, hypertension and LDL-Cholesterol. Therefore, CCTA may be useful for risk stratification of coronary artery disease as added value over CACS in selected populations with low CACS who have predictors of significant NCP.

Clinical characteristics of coronary drug-eluting stent fracture: insights from a two-center des registry.

Stent fracture (SF) has been implicated as a risk factor for in-stent restenosis, but its incidence and clinical characteristics are not well established. Therefore we investigated the conditions associated with stent fracture and its clinical presentation and outcome. Between 2004 and 2007, consecutive cases of SF were collected from the Seoul National University Hospital. Clinical characteristics and outcome of patients with fractured stents were compared with a ten-fold cohort of age and gender matched controls (n = 236). A total of 4,845 patients received percutaneous coronary intervention and 3,315 patients (68.4%) underwent angiographic follow-up. Twenty-eight fractured stents were observed in 24 patients. The incidence of SF was 0.89% for sirolimus-eluting stents (SES) and 0.09% for paclitaxel-eluting stents. Chronic kidney disease, stent implantation in the right coronary artery (RCA), and SES use were independent predictors of drug-eluting stent fracture by multivariate analysis. SF was significantly associated with binary restenosis (11.4% vs 41.7%, P < 0.001) and increased risk of target lesion revascularization (8.1% vs 33.3%, P = 0.001). Patients with SF but without significant restenosis showed excellent outcome despite only medical treatment. In conclusion, SF is associated with increased rates of restenosis and repeat revascularization. Significant risk factors include chronic kidney disease, RCA intervention, and SES use.

Sirolimus- vs. paclitaxel-eluting stents for the treatment of unprotected left main coronary artery stenosis: complete 2-year follow-up of a two-center registry.

BACKGROUND: The feasibility of percutaneous coronary intervention (PCI) using drug-eluting stents and its comparability with bypass surgery in treatment of unprotected left main coronary artery (LMCA) stenosis has been shown previously. We compared the mid-to long-term outcome between sirolimus-(SES) vs. paclitaxel-eluting stents (PES) in an all-comer analysis that included all patients with unprotected LMCA stenosis who underwent PCI with SES or PES. METHODS: From March 2003 and June 2007, 196 patients underwent PCI with SES or PES for unprotected LMCA stenosis at Seoul National University Main or Bundang Hospital; SES was implanted in 141 patients and PES in 55 patients. The baseline clinical and procedural characteristics were mostly similar between the SES and PES group. RESULTS: After 2 years of follow-up, there were no differences in the rate of cardiac death (9.1% vs. 8.5%) and nonfatal MI (5.5% vs. 2.8%) between the two groups. However, the risk of repeat revascularization tended to be lower in the SES group compared with the PES group [TLR, 9.9% vs. 20.0% (P=0.06); TVR, 17.7% vs. 30.9% (P=0.05)], which did not reach statistical significance. The rate of stent thrombosis (ST) was also similar between the two groups (3.6% vs. 2.1% for definite ST, 3.6% vs. 2.8% for definite+probable ST). CONCLUSIONS: In all-comers undergoing first generation DES implantation for unprotected LMCA stenosis, PES and SES showed comparable 2-year clinical results regarding hard endpoints and major adverse cardiac events.

Long-term clinical outcome of chronic total occlusive lesions treated with drug-eluting stents: comparison of sirolimus-eluting and paclitaxel-eluting stents.

BACKGROUND: There are few studies comparing the efficacy of different drug-eluting stents and their long-term clinical outcomes in percutaneous coronary intervention (PCI) of chronic total occlusive (CTO) lesions. METHODS AND RESULTS: To compare the efficacy of sirolimus-eluting stents (SES) and paclitaxel-eluting stents (PES) for CTO, and to identify predictors of outcome after PCI, 200 patients with at least 1 successfully revascularized CTO were enrolled into either a SES (n=132) or PES (n=71) group. At 6-9-month angiographic follow-up, SES was superior to PES (late loss 0.27+/-0.60 vs 0.53+/-0.62 mm, P=0.04). During mean follow-up of 2 years, the SES group had a significantly lower cumulative target vessel failure (TVF) rate than the PES group (14.9% vs 28.4%, P=0.01), as a consequence of lower target vessel revascularization (9.7% vs 23.9%, P=0.01) and also a partially lower rate of myocardial infarction (MI: 3.1% vs 7.6%, P=0.04). SES was also superior to PES in both early (9 months) TVF (P=0.02 for log-rank test, respectively). Predictors for TVF were use of PES (hazard ratio (HR) 3.81, P<0.01), previous history of MI (HR 4.06, P<0.01), diabetes (HR 2.07, P=0.04) and chronic kidney disease (CKD; HR 3.56, P=0.05). CONCLUSIONS: CTO lesions treated with SES showed better angiographic and long-term clinical outcomes than those treated with PES. Factors such as stent type, infarct-related CTO, diabetes and CKD affect the outcome of CTO intervention.

One year clinical and six month angiographic results of drug eluting stents for ST elevation acute myocardial infarction: 'real world' comparison between sirolimus- and paclitaxel-eluting stents.

BACKGROUND: Concerns about safety of drug eluting stents have stirred up controversy on their use in patients with acute STEMI. It is also unknown whether differences in efficacy and safety exist between sirolimus- (SES) and paclitaxel-eluting stents (PES). OBJECTIVE: To investigate the difference in angiographic results and clinical outcome between SES and PES in the treatment of acute STEMI, we analyzed "real world" 6 months angiographic and 1 year clinical outcome of 244 patients, comparing the results between SES and PES. METHODS: 244 consecutive acute STEMI patients were analyzed retrospectively (185 patients in SES group (Group S), 59 patients in PES group (Group P). Immediate post PCI and six month angiographic findings were analyzed by quantitative coronary angiography. Clinical events up to 1 year including cardiovascular death, myocardial infarction, and target lesion revascularization were also analyzed. RESULTS: Baseline clinical and immediate post-procedure angiographic characteristics were similar in the two groups except for mean stent diameter and length which was slightly wider and shorter in group P compared with group S (Mean stent diameterxlength: 3.12+/-0.34x24.4+/-5.1 vs. 3.01+/-0.34x26.6+/-7.2 mm in group P vs. S, p=0.02, p=0.03). At six months, late loss was significantly greater in group P compared with group S (0.35+/-0.62 vs. 0.07+/-0.42, p<0.01), although the difference in binary restenosis was not statistically significant. Diameter stenosis, which was similar immediately after PCI, was significantly greater in group P (22.0+/-17.1 vs. 15.6+/-13.4%, p=0.02). At 1 year, the incidence of stent thrombosis was similar in both groups (5.1% vs. 3.8% for group P vs. C). There were no differences between the two groups up to 1 year with regard to cardiovascular death, nonfatal myocardial infarction, and TLR. The free from adverse event rate was not statistically different between the two groups (84.2% vs. 90.2%, p=0.20 for group P vs. C). CONCLUSION: In this group of Korean acute STEMI patients, SES stent showed lower late loss compared to PES at 6 months angiographic follow up, but there was no difference in clinical outcome up to 1 year.