Unprotected left main stenting with a second-generation drug-eluting stent: one-year outcomes of the LEMAX Pilot study

Management of failed stenting of the unprotected left main coronary artery

Percutaneous coronary intervention (PCI) is increasingly accepted as treatment for unprotected left main coronary artery (ULMCA) disease especially in those patients who are unsuitable for cardiac surgery. Treatment of any stent failure is associated with increased complexity and worse clinical outcomes when compared with de novo lesion revascularization. Intracoronary imaging has provided new insight into mechanisms of stent failure and treatment options have developed considerably over the last decade. There is paucity of evidence on the management strategy for stent failure in the specific setting of ULMCA. Treating any left main with PCI requires careful consideration and consequently treatment of failed stents in ULMCA is complex and provides unique challenges. Consequently, we provide an overview of ULMCA stent failure, proposing a tailored algorithm to guide best management and decision in daily clinical practice, with a special focus on intracoronary imaging characterization of causal mechanisms and specific technical and procedural considerations.

Long-term outcome in patients treated with first- versus second-generation drug-eluting stents for the treatment of unprotected left main coronary artery stenosis

OBJECTIVE AND BACKGROUND

The study aim is to provide long-term clinical outcome after percutaneous coronary intervention (PCI) for unprotected left main coronary arteries (ULMCA) stenosis with the first-generation (1^st -gen) drug-eluting stents (DES) in comparison to 2^nd -gen DES, since this is largely unknown.

METHODS

Between May 2002, and December 2014, a consecutive series of 656 all-comer patients underwent a PCI for ULMCA stenosis at the Erasmus Medical Center. A total of 235 patients were treated with 1^st -gen DES, while a total of 421 patients were treated with 2^nd -gen DES.

RESULTS

Overall, the population consisted of 73% males and 58% presented with an acute coronary syndrome. Median follow-up time was 1,361 days (range from 0 to 5,031). At 5 years, the cumulative incidence of major adverse clinical events (the primary composite endpoint of all-cause death, any myocardial infarction or target lesion revascularization; MACE) did not differ between 1^st - and 2^nd -gen DES (36.8 vs. 38.6%, respectively, Log Rank p = .79, adjusted hazard ratio [HR] = 1.28 [95% confidence interval (CI) 0.94-1.74]). No difference was found in the individual endpoints of all-cause mortality (29.5 vs. 29% respectively, p = .88, adjusted HR = 1.19 [95% CI, 0.84-1.68]), target vessel myocardial infarction (5.0 vs. 8.4%, p = 0.17, adjusted HR = 1.75 [95% CI, 0.78-3.96]) and target lesion revascularization (8.1 vs. 9.8%, p = .94, adjusted HR = 1.16 [95% CI, 0.59-2.29]) between the 1^st - and 2^nd -gen DES cohorts, respectively.

CONCLUSIONS

In this large cohort of consecutive patients treated for ULMCA stenosis, no significant differences were found in the safety and efficacy of 1^st versus 2^nd -gen DES at 5 years follow-up.

Current Interventions for the Left Main Bifurcation

Contemporary clinical trials, registries, and meta-analyses, supported by recent results from the EXCEL (Everolimus-Eluting Stents or Bypass Surgery for Left Main Coronary Artery Disease) and NOBLE (Percutaneous Coronary Angioplasty Versus Coronary Artery Bypass Grafting in Treatment of Unprotected Left Main Stenosis) trials, have established percutaneous coronary intervention of left main coronary stenosis as a safe alternative to coronary artery bypass grafting in patients with low and intermediate SYNTAX (Synergy Between Percutaneous Coronary Intervention With Taxus and Cardiac Surgery) scores. As left main percutaneous coronary intervention gains acceptance, it is imperative to increase awareness for patient selection, risk scoring, intracoronary imaging, vessel preparation, and choice of stenting techniques that will optimize procedural and patient outcomes.

Safety and efficacy of lesion preparation with the AngioSculpt Scoring Balloon in left main interventions: the ALSTER Left Main registry

AIMS

Left main interventions require optimal initial results for good clinical outcome. Lesion preparation with the AngioSculpt Scoring Balloon (ASB) combined with the provisional T-stenting technique, if proven safe, might lead to better lumen gain and better clinical outcome. The aim of this registry was to investigate the safety and efficacy of the ASB as an option for lesion preparation in unprotected left main interventions (ULMI).

METHODS AND RESULTS

Out of the all-comers unprotected left main registry (ULMI ALSTER), 47 patients with elective ULMI fulfilled the inclusion criteria for this study. The endpoints were acute lumen gain and 12-month MACCE. The drop-out rate was 4%. The provisional T-stenting technique was used in 97% of distal ULMI. The interventions were grouped according to use of ASB with an in-house, historical no-ASB patient control group. Lumen gain was 1.63±0.12 mm in the ASB group (n=34) and 1.35±0.12 mm in the no-ASB group (n=8, p=0.26), respectively. The use of the ASB was safe. Intravascular ultrasound (IVUS) data for 21 patients showed numerically greater lumen area gain of 3.14±0.33 mm2 in the ASB group compared to 2.33±0.88 mm2 with the conventional technique. TLR/TVR was 6.6% overall. Twelve-month MACCE was 12.5% (4/32) for ASB and 15.4% (2/13) in the historical control group.

CONCLUSIONS

Adding ASB lesion preparation to the standard provisional T-stenting technique for ULMI is feasible and safe. Low TLR and TVR rates were observed. Lesion preparation led to a numerically larger lumen gain; the data allow valid power statistics to show this approach as leading to improved outcome in a possible randomised trial.

Comparison Between 1- and 2-Stent Strategies in Unprotected Distal Left Main Disease

Background—

There are only little data available on the comparison of clinical outcomes between a 1-stent strategy (1-SS) and a 2-stent strategy (2-SS) for percutaneous coronary intervention in unprotected distal left main disease.

Methods and Results—

Between April 2005 and August 2011, we recruited 937 consecutive unprotected distal left main patients treated with drug-eluting stents (1-SS, 608 patients; 2-SS, 329 patients). Major adverse cardiovascular events were defined as all-cause death, myocardial infarction, or target lesion revascularization (TLR) during the median follow-up period of 1592 days. Furthermore, the individual components of major adverse cardiovascular events, cardiac death, and stent thrombosis were evaluated. More complex lesions were seen with 2-SS than with 1-SS. Cardiac death occurred more frequently with 1-SS than with 2-SS (propensity score–adjusted hazard ratio, 0.52; 95% confidence interval, 0.29–0.64; P =0.03), whereas TLR occurred more frequently with 2-SS than with 1-SS (propensity score–adjusted hazard ratio, 1.59; 95% confidence interval, 1.15–2.20; P =0.005). TLR was mainly driven by revascularizations after restenosis at the ostial left circumflex artery (propensity score–adjusted hazard ratio, 1.94; 95% confidence interval, 1.33–2.82; P =0.001). However, there were no differences in major adverse cardiovascular events, all-cause death, stent thrombosis, and myocardial infarction. Of the 139 pairs that were propensity score matched, only TLRs were significantly higher in the 2-SS group (hazard ratio, 1.59; 95% confidence interval, 1.00–2.53; P =0.05).

Conclusions—

The difference between 1-SS and 2-SS in percutaneous coronary intervention for unprotected distal left main disease may be summarized by the high incidence of TLR, mainly because of restenosis at the ostial left circumflex artery in the 2-SS group.

Clinical Outcome After DK Crush Versus Culotte Stenting of Distal Left Main Bifurcation Lesions: The 3-Year Follow-Up Results of the DKCRUSH-III Study

OBJECTIVES

The present study aimed to investigate the difference in major adverse cardiac events (MACE) at 3 years after double-kissing (DK) crush versus culotte stenting for unprotected left main distal bifurcation lesions (LMDBLs).

BACKGROUND

The multicenter and randomized DKCRUSH-III (Comparison of double kissing crush versus culotte stenting for unprotected distal left main bifurcation lesions: results from a multicenter, randomized, prospective study) showed that DK crush stenting was associated with fewer MACE at 1-year follow-up in patients with LMDBLs compared with culotte stenting. Here, we report the 3-year clinical outcome of the DKCRUSH-III study.

METHODS

A total of 419 patients with LMDBLs who were randomly assigned to either the DK crush or culotte group in the DKCRUSH-III study were followed for 3 year. The primary endpoint was the occurrence of a MACE at 3 years. Stent thrombosis (ST) was the safety endpoint. Patients were classified by simple and complex LMDBLs according to the DEFINITION (Definition and Impact of Complex Bifurcation Lesions on Clinical Outcomes After Percutaneous Coronary Intervention Using Drug-Eluting Stents) study criteria.

RESULTS

At 3 years, MACE occurred in 49 patients the culotte group and in 17 patients in the DK crush group (cumulative event rates of 23.7% and 8.2%, respectively; p < 0.001), mainly driven by increased myocardial infarction (8.2% vs. 3.4%, respectively; p = 0.037) and target-vessel revascularization (18.8% vs. 5.8%, respectively; p < 0.001) between groups. Definite ST rate was 3.4% in the culotte group and 0% in the DK crush group (p = 0.007). Complex LMDBLs were associated with a higher rate of MACE (35.3%) at 3 years compared with a rate of 8.1% in patients with simple LMDBLs (p < 0.001), with an extremely higher rate in the culotte group (51.5% vs. 15.1%, p < 0.001).

CONCLUSIONS

Culotte stenting for LMDBLs was associated with significantly increased rates of MACE and ST. (Double Kissing [DK] Crush Versus Culotte Stenting for the Treatment of Unprotected Distal Left Main Bifurcation Lesions: DKCRUSH-III, a Multicenter Randomized Study Comparing Double-Stent Techniques; ChiCTR-TRC-11001877).

Two-year outcomes following unprotected left main stenting with first vs. new-generation drug-eluting stents: the FINE registry

AIMS

To assess two-year outcomes following first vs. new-generation drug-eluting stent (DES) implantation in unprotected left main (ULMCA) percutaneous coronary intervention.

METHODS AND RESULTS

All eligible patients from our two-centre registry treated with first and new-generation DES from October 2006 to November 2010 were analysed. The study objective was major adverse cardiac events (MACE), defined as all-cause mortality, target vessel revascularisation (TVR) and myocardial infarction (MI) at two years. In total, 186 patients were included: 93 (50.0%) treated with first vs. 93 (50.0%) with new-generation DES. No differences were observed in baseline clinical characteristics except for higher EuroSCORE with new-generation DES (3.6±2.5 vs. 4.6±2.7; p=0.007). No significant difference was observed in stenting techniques; two stents were used respectively in 53.8% vs. 44.1% (p=0.187). Notably, intravascular ultrasound guidance was more frequent with new-generation DES (46.2% vs. 61.3%; p=0.040). At 730.0 (interquartile range 365.5-1,224.5) days, there was a trend towards improved MACE with new-generation DES (31.2% vs. 19.6%; p=0.070) and a significant reduction in TVR (23.7% vs. 12.0%; p=0.038) and MI (4.3% vs. 0%; p=0.044). Notably, there were four cases of definite stent thrombosis (ST) with first vs. none with new-generation DES (p=0.044).

CONCLUSIONS

In our study, new-generation DES had a trend for less MACE and improved results with regard to MI, TVR and definite ST at two-year follow-up.

Left Main Percutaneous Coronary Intervention

Significant unprotected left main stem (ULMS) disease is in approximately 5% to 7% of patients undergoing coronary angiography. Historically, coronary artery bypass grafting has been the gold standard treatment of these patients. With recent advances in stent technology, adjunctive pharmacotherapy, and operator experience, percutaneous coronary intervention (PCI) is increasingly regarded as a viable alternative treatment option, especially in patients with favorable coronary anatomy (low and intermediate SYNTAX (Synergy Between Percutaneous Coronary Intervention with TAXUS and Cardiac Surgery) scores). This article aims to discuss the evidence supporting PCI for ULMS disease, current guidelines, and technical aspects.

Drug-eluting stents in unprotected left main coronary artery disease

Though coronary bypass graft surgery (CABG) has traditionally been the cornerstone of therapy in patients with unprotected left main coronary artery (ULMCA) disease, recent evidence supports the use of percutaneous coronary intervention in appropriate patients. Indeed in patients with ULMCA disease, drug-eluting stents (DES) have shown similar incidence of hard end points, fewer periprocedural complications and lower stroke rates compared with CABG, though at the cost of increased revascularization with time. Furthermore, the availability of newer efficacious and safer DES as well as improvements in diagnostic tools, percutaneous techniques and, importantly, a better patient selection, allowed percutaneous coronary intervention a viable alternative to CABG of left main-patients with low disease complexity; however, even in this interventional era characterized by efficacious DES, patients with ULMCA disease remain a challenging high-risk population where outcomes strongly depend on clinical characteristics, anatomical disease complexity and extension and operator's experience. This review summarizes the role of DES in ULMCA disease patients.

Comparison of paclitaxel-eluting stents (Taxus) and everolimus-eluting stents (Xience) in left main coronary artery disease with 3 years follow-up (from the ESTROFA-LM registry)

Evidence regarding therapy with drug-eluting stents in the left main coronary artery (LM) is based mostly on trials performed with first-generation drug-eluting stents. The aim of this study was to evaluate long-term clinical outcomes after treatment for unprotected LM disease with paclitaxel-eluting stents (PES) and everolimus-eluting stents (EES). The ESTROFA-LM is a multicenter retrospective registry including consecutive patients with unprotected LM disease treated with PES or EES. A total of 770 patients have been included at 21 centers, 415 with treated PES and 355 with EES. Treatment with 2 stents was more frequent with PES (17% vs 10.4%, p = 0.007), whereas intravascular ultrasound was more frequently used with EES (35.2% vs 26%, p = 0.006). The 3-year death and infarction survival rates were 86.1% for PES and 87.3% for EES (p = 0.50) and for death, infarction, and target lesion revascularization were 83.6% versus 82% (p = 0.60), respectively. Definite or probable thrombosis was 1.6% for PES and 1.4% for EES (p = 0.80). The use of 2 stents, age, diabetes, and acute coronary syndromes were independent predictors of mortality. In the subgroup of distal lesions, the use of intravascular ultrasound was an independent predictor of better outcome. Comparison of propensity score-matched groups did not yield differences between the 2 stents. In conclusion, the results of this multicenter registry show comparable safety and efficacy at 3 years for PES and EES in the treatment of LM disease. The use of bifurcation stenting techniques in distal lesions was a relevant independent predictor for events. The use of intravascular ultrasound appears to have a positive impact on patients treated for LM distal disease.

Mid-term clinical outcomes of ACS and non-ACS patients treated with everolimus-eluting stents

Drug-eluting stents (DES) have proven to be effective for reducing the rate of restenosis, whereas stent thrombosis (ST) after DES implantation has raised safety concerns. Everolimus-eluting stents (EES) are a new generation of DES that have demonstrated safety and efficacy compared with first-generation DES. However, the use of EES in patients presenting with acute coronary syndrome (ACS) has not been adequately investigated. We compared the clinical outcomes between the ACS and non-ACS groups treated with EES. A total of 335 consecutive patients who received EES implantation between January 2010 and January 2011 were investigated (ACS; n = 172, non-ACS; n = 163). Clinical outcome data were obtained for 94.3% of the patients. Follow-up angiography was performed in 58.5% of all patients. The median follow-up period was 8 months in both groups. Clinical outcomes were not statistically different between the groups. The rate of target lesion revascularization (TLR) was 2.5% in the ACS group and 3.8% in the non-ACS group (P = 0.37). MACE occurred in 8.2% of the ACS group and 10.2% of the non-ACS group (P = 0.54). A definite ST was identified in one patient in each group (P = 0.75). The unadjusted cumulative event rates estimated by the Kaplan-Meier method and the log-rank test showed no significant difference between the groups for TLR, target vessel revascularization (TVR), all-cause death, or MACE. In conclusion, EES was safe and efficacious for patients presenting with ACS, as well as for those with non-ACS during a mid-term follow-up period.

Reproducibility and factors influencing the assessment of the SYNTAX score in the left main Xience study

BACKGROUND

As assessment of SYNTAX score is made by visual estimate of coronary angiography, discrepancies between evaluations by different observers and the impact of observer experience have not yet been evaluated.

METHODS

Using the data of 166 patients with unprotected left main lesions treated with the second generation everolimus-eluting stent, we sought to analyze SYNTAX score assessment provided by one junior and two independent senior observers and to assess the impact of the quality of angiographies on the reproducibility of SYNTAX score determination. Intra-observer variability was assessed by a senior observer by analyzing 50 sets of angiograms after an interval of at least 6 weeks.

RESULTS

The weighted kappa value for the inter-observer reproducibility of SYNTAX score classified as tertiles, according to SYNTAX trial, was 0.71 and the intra-observer weighted kappa value was 0.79. When compared with junior's measurements, SYNTAX score assessed by senior investigators was 0.46 and 0.50. Changes in SYNTAX score classification were arbitrarily responsible for changes in weighted kappa values. Angiograms showing the higher rates of discrepancies between observers were of lower quality, when compared with random angiograms. SYNTAX score was closely correlated to 1-year incidence of major adverse cerebro- and cardiovascular events for both junior and senior readers.

CONCLUSIONS

SYNTAX score was slightly underestimated by junior reader, when compared with experienced operators. Inter- and intra-observer reproducibility of experienced operators was very acceptable. SYNTAX score evaluation was clearly related to the quality of angiograms. SYNTAX score was correlated to 1-year incidence of major cardiac and cerebrovascular events (MACCE) in all readers.