Percutaneous coronary intervention with stent implantation versus coronary artery bypass surgery for treatment of left main coronary artery disease: is it time to change guidelines?

In silico model of stent performance in multi-layered artery using 2-way fluid-structure interaction: Influence of boundary conditions and vessel length

BACKGROUND AND OBJECTIVE

Atherosclerotic lesions of coronary arteries (stenosis) are caused by the buildup of lipids and blood-borne substances within the artery wall. Their qualitative and rapid assessment is still a challenging task. The primary therapy for this pathology involves implanting coronary stents, which help to restore the blood flow in atherosclerosis-prone arteries. In-stent restenosis is a stenting-procedure complication detected in about 10-40% of patients. A numerical study using 2-way fluid-structure interaction (FSI) assesses the stenting procedure quality and can decrease the number of negative post-operative results. Nevertheless, boundary conditions (BCs) used in simulation play a crucial role in implementation of an adequate computational analysis.

METHODS

Three CoCr stents designs were modelled with the suggested approach. A multi-layer structure describing the artery and plaque with anisotropic hyperelastic mechanical properties was adopted in this study. Two kinds of boundary conditions for a solid domain were examined - fixed support (FS) and remote displacement (RD) - to assess their impact on the hemodynamic parameters to predict restenosis. Additionally, the influence of artery elongation (short-artery model vs. long-artery model) on numerical results with the FS boundary condition was analyzed.

RESULTS

The comparison of FS and RD boundary conditions demonstrated that the variation of hemodynamic parameters values did not exceed 2%. The analysis of short-artery and long-artery models revealed that the difference in hemodynamic parameters was less than 5.1%, and in most cases, it did not exceed 2.5%. The RD boundary conditions were found to reduce the computation time by up to 1.7-2.0 times compared to FS. Simple stent model was shown to be susceptible to restenosis development, with maximum WSS values equal to 183 Pa, compared to much lower values for other two stents.

CONCLUSIONS

The study revealed that the stent design significantly affected the hemodynamic parameters as restenosis predictors. Moreover, the stress-strain state of the system artery-plaque-stent also depends on a proper choice of boundary conditions.

One-year Outcome of Different Unprotected Left Main Percutaneous Coronary Interventions Techniques in Acute Coronary Syndromes

Background: We intended in this study to evaluate the impact of the different techniques of unprotected left main coronary artery (ULMCA) stenting on the clinical outcomes. Methods: The study included 65 patients with ACS and left main disease subjected to UPLMCA intervention [46 males (70.8%) with median(Q1-Q3) age of 63(53-70) years old] in an observational prospective cohort study. Data were collected through reviewing patient’s medical records and angiographic procedures. Angiographic assessment included evaluation of Syntax II score, EURO II score, and TIMI flow grading. The primary outcome was the major adverse cardiac and cerebral events (MACCE) at 1 year while the secondary outcomes included the development of acute kidney injury (AKI), one year mortality, and need for CABG post PCI. Results: One-year MACCE was 46.2 % when the angle between LAD and LCX was>70o compared to 81.5% when it was less than 70o (P=0.008). The wide angle was also associated with 0% 1-year mortality compared to 18.5% for narrow angle, a difference which is statistically significant (P=0.03). The 1-year MACCE was 35.7% compared to 74.4% when it was not used (P=0.013). When POT was used, the 1-year MACCE was 47.6% compared to 75% when it was not used (P=0.041). None of the other studied parameters including those related to procedure technique was significantly affecting the outcome in our study. Conclusion: We concluded that the non-use of FKI nor POT together with the lower angulation between LAD and LCX could predict worse clinical outcome at one-year in unprotected left main PCI.

Intensive care outcome of left main stem disease surgery: A single center three years’ experience

BACKGROUND

Left main coronary artery (LMCA) supplies more than 80% of the left ventricle, and significant disease of this artery carries a high mortality unless intervened surgically. However, the influence of coronary artery bypass grafting (CABG) surgery on patients with LMCA disease on morbidity intensive care unit (ICU) outcomes needs to be explored. However, the impact of CABG surgery on the morbidity of the ICU population with LMCA disease is worth exploring.

AIM

To determine whether LMCA disease is a definitive risk factor of prolonged ICU stay as a primary outcome and early morbidity within the ICU stay as secondary outcome.

METHODS

Retrospective descriptive study with purposive sampling analyzing 399 patients who underwent isolated urgent or elective CABG. Patients were divided into 2 groups; those with LMCA disease as group 1 (75 patients) and those without LMCA disease as group 2 (324 patients). We correlated ICU outcome parameters including ICU length of stay, post-operative atrial fibrillation, acute kidney injury, re-exploration, perioperative myocardial infarction, post-operative bleeding in both groups.

RESULTS

Patients with LMCA disease had a significantly higher prevalence of diabetes (43.3% vs 29%, P = 0.001). However, we did not find a statistically significant difference with regards to ICU stay, or other morbidity and mortality outcome measures.

CONCLUSION

Post-operative performance of Patients with LMCA disease who underwent CABG were comparable to those without LMCA involvement. Diabetes was more prevalent in patients with LMCA disease. These findings may help in guiding decision making for future practice and stratifying the patients’ care.

Bilateral internal thoracic artery grafting in patients with left main disease: a single-center experience

OBJECTIVE

We compared early and long-term outcomes between bilateral internal thoracic artery (BITA) grafting and single internal thoracic artery (SITA) grafting in patients with LM disease.

METHODS

We evaluated the outcomes of all patients with LM disease who underwent revascularization in our center during 1996-2011. Variables that were adjusted for in a multivariate analysis and in propensity matching included age, sex, comorbid diseases, repeat operation, the number of diseased vessels, other conduits used, the use of sequential grafting, the number of grafts constructed, and the operative era (1996-2000 vs. 2001-2011).

RESULTS

In total, 949 patients with LM disease underwent BITA grafting and 564 underwent SITA grafting during the study period. SITA patients were more often female and more likely to have comorbidities such as chronic obstructive pulmonary disease, ejection fraction <30%, recent myocardial infarction, diabetes, congestive heart failure, chronic renal failure, and peripheral vascular disease, and to have undergone an emergency operation. We found no statistically significant difference between the SITA and BITA groups in 30-day mortality (4.8% vs. 3.3%, P = 0.136), sternal wound infection (2.0% vs. 2.4%, P = 0.548), and stroke (3.2% vs. 4.4%, P = 0.234). BITA patients had improved long-term survival (70.1% vs. 52.0% p<0.001), median follow-up of 15 years. In multivariate analysis, after propensity score matching (477 matched pairs), this finding was not statistically significant (P = 0.135).

CONCLUSION

This study did not demonstrate a clear benefit of BITA grafts among patients with LM disease.

Long-Term Clinical Outcomes and Optimal Stent Strategy in Left Main Coronary Bifurcation Stenting

OBJECTIVES

This study sought to investigate the long-term clinical effects of stent generation and stent strategy for left main coronary artery (LMCA) bifurcation lesion treatment.

BACKGROUND

Limited data are available to assess long-term clinical outcomes after stenting, including use of current-generation drug-eluting stent (C-DES) for treatment of LMCA bifurcation lesions.

METHODS

A total of 1,353 patients who were recorded in 2 multicenter real-world registries were treated by either early-generation drug-eluting stent (E-DES) (n = 889) or C-DES (n = 464). Primary endpoint was major adverse cardiovascular events (MACE). MACE was defined as a composite of cardiac death or myocardial infarction, stent thrombosis, and target lesion revascularization rates during 3-year follow-up. The authors further performed propensity-score adjustment for clinical outcomes.

RESULTS

During 3-year follow-up, the overall MACE rate was 8.7%. Use of a 1-stent strategy resulted in better clinical outcomes than use of a 2-stent strategy (4.7% vs. 18.6%, hazard ratio [HR]: 3.71; 95% confidence interval [CI]: 2.55 to 5.39; p < 0.001). Use of C-DES resulted in a lower MACE rate compared with using E-DES (4.6% vs. 10.9%, HR: 0.55; 95% CI: 0.34 to 0.89; p = 0.014), especially for the 2-stent strategy. For patients with C-DES, the presence of chronic kidney disease and pre-intervention side branch diameter stenosis ≥50% were significant independent predictors of MACE.

CONCLUSIONS

Intervention of LMCA bifurcation lesions using DES implantation demonstrated acceptable long-term clinical outcomes, especially in C-DES patients. Use of a 1-stent strategy resulted in better clinical benefits than using a 2-stent strategy.

Discrepancy between the European clinical guidelines and myocardial revascularization in patients with stable coronary artery disease in Russia

OBJECTIVE

In European Society of Cardiology/European Association for Cardio-Thoracic Surgery (ESC/EACTS) guidelines, six indications have been proposed for making a decision on myocardial revascularization in patients with stable coronary artery disease (CAD). Our aim was to study a discrepancy between the actual clinical situation and ESC/EACTS indications on performing the revascularization in patients with CAD in Russia.

DESIGN AND SETTING

We used retrospective clinical data on patients with stable CAD enrolled in the 2012-2015 Russian Registry of Hypertension, Coronary Artery Disease, and Chronic Heart Failure.

PARTICIPANTS

A total of 1522 patients with CAD (aged 53.0 ± 8.5 years, 76.2% male) were used for analysis.

INTERVENTIONS

All patients were divided into two groups: 591 patients with performed myocardial revascularization (named as R-CAD) and 931 patients refused from revascularization (named as NR-CAD). Factors associated with revascularization performance were identified by discriminant function analysis.

MAIN OUTCOME MEASURES

ESC/EACTS indications for revascularization were assessed.

RESULTS

A total of 1196 patients with CAD had any ESC/EACTS indication for revascularization, but only 40.2% of them had performed invasive coronary intervention. Myocardial revascularization was appropriate in 81.4% of R-CAD patients and 76.8% of NR-CAD patients. The main factor of revascularization performance was any stenosis >50% and grades III-IV of stable angina. With non-performed revascularization, the following factors were associated: limiting angina or angina equivalent, unresponsive to medical therapy, atherosclerotic peripheral arterial disease and increasing the New York Heart Association class of chronic heart failure. Most ESC/EACTS indications had little effect on decision-making on revascularization.

CONCLUSION

There is a discrepancy between the actual clinical situation and ESC/EACTS guidelines on myocardial revascularization in patients with stable CAD in Russia.

Effect of Age and Sex on Outcomes After Stenting or Bypass Surgery in Left Main Coronary Artery Disease

Age and sex contribute to determining coronary revascularization strategies for patients with left main coronary artery (LMCA) disease. We examined age- and sex-related differences in comparative outcomes after percutaneous coronary intervention (PCI) or coronary-artery bypass grafting (CABG) for LMCA disease. A total of 4,001 patients with LMCA disease (men, n = 3,100, women, n = 901) who underwent PCI (n = 2,615) or CABG (n = 1,386) from the Interventional Research Incorporation Society-Left MAIN Revascularization registry were analyzed. Patients were stratified into subgroups according to the tertiles of age (<60 years, 60 to 69 years, and ≥70 years) and sex. The primary outcome was the composite of death from any cause, myocardial infarction, or stroke. During the median 6.3 years of follow-up, the adjusted risks for primary outcome after PCI relative to CABG were similar in patients aged <60 years (hazard ratio [HR]: 0.64, 95% confidence interval [CI]: 0.35 to 1.16), 60 to 69 years (HR: 1.21; 95% CI: 0.82 to 1.80), and ≥70 years (HR: 0.90; 95% CI: 0.66 to 1.22) with no significant age-related interactions (P_interaction = 0.57). The primary outcome risks following PCI versus CABG were similar between male (HR: 0.92; 95% CI: 0.72 to 1.17) and female (HR: 0.89; 95% CI: 0.52 to 1.50) (P_interaction = 0.65). Significant interactions were absent for age or sex and revascularization type for all-cause mortality (P_interaction = 0.34 for age and P_interaction = 0.99 for sex), repeat revascularization (P_interaction = 0.10 for age and P_interaction = 0.65 for sex), and major adverse cardiac or cerebrovascular events (P_interaction = 0.29 for age and P_interaction = 0.30 for sex). In conclusion, there were no significant age- or sex-related differences in comparative outcomes after PCI or CABG for LMCA disease.

Percutaneous Coronary Intervention and Coronary Artery Bypass Grafting for the Treatment of Left Main Coronary Artery Disease

Severe stenosis of the left main coronary artery (LMCA) generally occurs as a result of atherosclerosis and compromises the blood supply to a wide area of myocardium, thereby increasing the risk of serious adverse cardiac events. Current revascularization strategies for patients with significant LMCA disease include coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI), both of which have a range of advantages and disadvantages. In general, PCI is associated with a lower rate of periprocedural adverse events and provides more rapid recovery, while CABG provides more durable revascularization. Most clinical trials comparing PCI and CABG for the treatment of LMCA disease have shown PCI to be non-inferior to CABG with respect to mortality and the serious composite outcome of death, myocardial infarction, or stroke in patients with low-to-intermediate anatomical complexities. Remarkable advancements in PCI standards, including safer and more effective stents, adjunctive intravascular imaging or physiologic evaluation, and antithrombotic treatment, may have contributed to these favorable results. This review provides an update on the current management of LMCA disease with an emphasis on clinical data and academic and clinical knowledge that supports the use of PCI in an increasing proportion of patients with LMCA disease.

Clinical outcomes of left main coronary artery disease patients undergoing three different revascularization approaches

Significant unprotected left main (LM) coronary artery disease is frequently associated with severe multivessel disease and increased mortality and morbidity compared with non-LM coronary artery disease. This study compared the clinical outcomes of patients with LM disease who received percutaneous coronary intervention (PCI) with stenting, conventional coronary-artery bypass grafting (C-CABG), and robot-assisted CABG (R-CABG).This retrospective study analyzed 472 consecutive LM disease patients who underwent three different revascularization approaches at a tertiary medical center between January 2005 and November 2013.Of the 472 LM disease patients, 139 received R-CABG, 147 received C-CABG, and 186 received PCI. The need for target vessel revascularization (TVR) was highest in the PCI group. The R-CABG group had significantly lower rates of in-hospital and follow-up all-cause deaths compared with the other 2 groups (1.4% vs. 3.4% and 9.7%, P = .0058; 13.7% vs. 29.3% and 29.6%, P = .0023, respectively). Patients in the R-CABG group had significantly lower rates of intra-aortic balloon pump assistance, and shorter duration of ICU and total hospital stay compared to patients in the C-CABG group. However, revascularization modality, SYNTAX scores, and residual SYNTAX scores were not independent predictors of in-hospital or long-term mortality.In this cohort of LM disease patients treated at a tertiary medical center, PCI is a reasonable choice in patients with less lesion complexity but who are older and have comorbidities. R-CABG is feasible in stable LM disease patients with high SYNTAX scores, and is an effective alternative to C-CABG in LM disease patients with few risk factors. However, revascularization modality per se was not a determinant for long-term mortality in our real-world practice.

Percutaneous coronary intervention using drug-eluting stents versus coronary artery bypass graft surgery in left main coronary artery disease an updated meta-analysis of randomized clinical trials

Objectives

To compare the safety and efficacy of percutaneous coronary intervention (PCI) using drug-eluting stent (DES) and coronary artery bypass graft (CABG) for the treatment of left main coronary artery (LMCA) disease.

Background

Several new randomized trials have recently examined the clinical outcomes of PCI and CABG in LMCA disease. However, the results of these studies were inconsistent.

Materials and Methods

We searched five online electronic databases to identify all the randomized clinical trials assessing the outcomes of PCI using DES and CABG in patients with LMCA. The clinical outcomes were the major adverse cardiac and cerebrovascular event (MACCE), all-cause death, myocardial infarction (MI), stroke, and repeat revascularization (RR).

Results

A total of 5 randomized clinical trials with 4595 LMCA patients were included in this meta-analysis. For one year follow-up, the results indicated that PCI were associated with a lower risk of stroke (RR = 0.21, 95% CI = 0.07–0.65, P = 0.007), a higher risk of RR (RR = 1.72, 95% CI = 1.28–2.33, P < 0.001) than CABG. Moreover, for long-term follow-up, there were significant higher risks of MACCE and RR with PCI versus CABG (MACCE: HR = 1.26, 95% CI = 1.11–1.44, P = 0.001; RR: HR = 1.70, 95% CI = 1.42–2.05, P < 0.001). However, there were no significant differences between the two groups in all-cause death and MI risks, regardless of follow-up duration.

Conclusions

PCI is noninferior to CABG in short term follow-up of patients with LMCA disease, but CABG is more safety and efficacy than PCI using DES in long-term follow-up.

Meta-Analysis of Randomized Control Trials Comparing Drug-Eluting Stents Versus Coronary Artery Bypass Grafting for Significant Left Main Coronary Narrowing

Previous meta-analyses showed that drug-eluting stent (DES) implantation may serve as an alternative to coronary artery bypass grafting (CABG) for unprotected left main coronary artery (ULMCA) stenosis, largely driven by data from registries. Hence, we performed a meta-analysis of randomized controlled trials (RCTs) to overcome this limitation. PubMed, the Cochrane Library, and Scopus were systematically searched through October 2016 to identify eligible RCTs. The primary outcomes were major adverse cardiac and cerebrovascular events (MACCE) at 1-year and long-term (≥3 years) follow-ups. This meta-analysis included 5 RCTs, totaling 4,595 patients with ULMCA disease. Compared with CABG, DES showed similar 1-year rates of MACCE (risk ratio [RR] 1.14, 95% confidence interval [CI] 0.91-1.42), all-cause death, and myocardial infarction, with a higher incidence of revascularization (RR 1.68, 95% CI 1.24-2.27) and lower incidence of stoke (RR 0.43, 95% CI 0.23-0.78). At long-term follow-up, DES placement was inferior to CABG in terms of MACCE (RR 1.27, 95% CI 1.13-1.43) and revascularization (RR 1.70, 95% CI 1.43-2.01). There was no difference in long-term risk of other outcomes between these 2 strategies. In conclusion, DES stenting and CABG for ULMCA disease yield comparable rates of MACCE at 1-year follow-up; however, CABG is associated with a decreased risk of long-term MACCE compared with DES, exclusively driven by the considerable reduction in revascularization events.

Drug-eluting stent placement versus coronary artery bypass surgery for unprotected left main coronary artery disease: A meta-analysis of randomized controlled trials

BACKGROUND

Coronary artery bypass grafting (CABG) is the standard of care for treating left main coronary lesions. However, recently published randomized controlled trials (RCT) have shown conflicting results. We sought to compare clinical outcomes of percutaneous coronary intervention (PCI) with drug-eluting stent placement to CABG using a meta-analysis of randomized controlled trials.

METHODS

A systemic search of Pubmed, Scopus, Cochrane library, and Clinicaltrials.gov was performed for randomized controlled trials comparing PCI with CABG in patients with left main stenosis. Data were analyzed using random effect models and Mantel-Haenszel methods. The primary outcome was major adverse cardiovascular and cerebral events (MACCE). The secondary outcomes were myocardial infarction, stroke, cardiac, and all-cause mortality. A subgroup analysis based on SYNTAX score was also performed.

RESULTS

A total of 4595 patients (2297 in the PCI group and 2298 in the CABG group) from five RCTs were included in the analysis. There were significant differences in MACCE (odds ratio [OR] 1.36, confidence interval [CI] 95%, 1.18-1.58, p-value: < 0.0001) and repeat revascularization (OR 1.85, CI 95%, 1.53-2.23, p-value: < 0.00001) favoring CABG. There were no significant differences in the incidence of myocardial infarction, stroke, or cardiac and all-cause mortality. Based on SYNTAX score, CABG was superior in terms of MACCE only in the subgroup with SYNTAX score of 33 or more.

CONCLUSIONS

CABG results in fewer MACCE and need for repeat revascularization than PCI in patients with unprotected left main disease.

Measurement of in vitro and in vivo stent geometry and deformation by means of 3D imaging and stereo-photogrammetry

PURPOSE

To quantify variability of in vitro and in vivo measurement of 3D device geometry using 3D and biplanar imaging.

METHODS

Comparison of stent reconstruction is reported for in vitro coronary stent deployment (using micro-CT and optical stereo-photogrammetry) and in vivo pulmonary valve stent deformation (using 4DCT and biplanar fluoroscopy). Coronary stent strut length and inter-strut angle were compared in the fully deployed configuration. Local (inter-strut angle) and global (dog-boning ratio) measures of stent deformation were reported during stent deployment. Pulmonary valve stent geometry was assessed throughout the cardiac cycle by reconstruction of stent geometry and measurement of stent diameter.

RESULTS

Good agreement was obtained between methods for assessment of coronary stent geometry with maximum disagreement of +/- 0.03 mm (length) and +/- 3 degrees (angle). The stent underwent large, non-uniform, local deformations during balloon inflation, which did not always correlate with changes in stent diameter. Three-dimensional reconstruction of the pulmonary valve stent was feasible for all frames of the fluoroscopy and for 4DCT images, with good correlation between the diameters calculated from the two methods. The largest compression of the stent during the cardiac cycle was 6.98% measured from fluoroscopy and 7.92% from 4DCT, both in the most distal ring.

CONCLUSIONS

Quantitative assessment of stent geometry reconstructed from biplanar imaging methods in vitro and in vivo has shown good agreement with geometry reconstructed from 3D techniques. As a result of their short image acquisition time, biplanar methods may have significant advantages in the measurement of dynamic 3D stent deformation.

Unprotected left main coronary artery disease in patients with low predictive risk of mortality

BACKGROUND

There has been an increasing use of percutaneous coronary intervention with drug-eluting stent (DES) in patients with unprotected left main coronary artery disease. We assessed whether coronary artery bypass grafting (CABG) would be superior to percutaneous coronary intervention with first-generation DES in patients with unprotected left main coronary artery disease.

METHODS

Between January 2003 and December 2007, a total of 295 patients with unprotected left main coronary artery disease were treated with Kurashiki Central Hospital, Okayama, Japan. Among these patients, 169 and 126 underwent CABG and percutaneous coronary intervention with DES, respectively. The average Society of Thoracic Surgeons' predictive risk of mortality score was 2.3±3.8%. We defined higher-risk and lower-risk patients as those with Society of Thoracic Surgeons' predictive risk of mortality scores higher than 2.3% (CABG, n=48; percutaneous coronary intervention, n=28) and lower than 2.3% (CABG, n=121; percutaneous coronary intervention, n=98), respectively. Survival, major adverse cardiac-related events, and target lesion revascularization were analyzed by the Kaplan-Meier method.

RESULTS

Between-group differences in favor of CABG were seen with respect to the rate of major adverse cardiac-related events and target lesion revascularization in both strata. In patients with lower scores according to the Society of Thoracic Surgeons' predictive risk of mortality, the cardiac death-free survival rate was significantly higher in CABG.

CONCLUSIONS

In this 5-year single-center experience, CABG is recommended for unprotected left main coronary artery disease, especially in patients with low scores in the Society of Thoracic Surgeons' predictive risk of mortality.

New era of left main coronary artery treatment strategy

For several decades of medical history, coronary-artery bypass grafting (CABG) has been regarded as the best treatment option for patients with unprotected left main coronary artery (LMCA) disease, considering lesion priority and its clinical consequences. Over the time, with remarkable advancements in techniques of percutaneous coronary intervention (PCI), supporting devices, and adjunctive pharmacologic therapy, PCI with DES implantation has appeared to be new and alternative option for optimal revascularization therapy for these patients. The available cumulative evidence suggests that the safety outcomes such as mortality or composite of death, myocardial infarction and stroke are similar among PCI and CABG for patients with LMCA disease, the only difference was the rate of repeat revascularization. Current evidence and ongoing large clinical trials may encourage interventional cardiologists to choose PCI with stenting as an alternative revascularization strategy for unprotected LMCA disease in future. Finally, this evidence will change the current clinical practice and the guideline of optimal revascularization strategy for unprotected LMCA disease.

Treatment of patients with left main coronary artery disease

OPINION STATEMENT

Considering lesion priority and its clinical consequences, coronary artery bypass grafting (CABG) has been a treatment of choice for revascularization in patients with significant left main coronary artery (LMCA) disease, However, with remarkable advancements in techniques of percutaneous coronary intervention (PCI), supporting devices, and adjunctive pharmacologic therapy, PCI with stenting has emerged to be a less invasive and feasible revascularization treatment for these patients. The cumulative evidence suggests that the safety outcomes such as mortality or composite of death, myocardial infarction, and stroke are similar among PCI and CABG, with the only difference being the rate of repeat revascularization. Based on these data, the current guideline of revascularization of LMCA disease has adopted an increasing off-label experience with stenting and clinical studies and been updated to partly approve PCI as a viable alternative (in level of class IIb) in selected patients. The choice of PCI or CABG for unprotected LMCA disease depends on several clinical and anatomic features, ensuring crucial patient selection to be a cornerstone for achieving favorable long-term outcomes. In patients with very complex anatomic features and concomitant diffuse multivessel disease, CABG is preferred so as to avoid procedural and future thrombotic risks and to provide more complete revascularization. By contrast, in patients with relatively simple LMCA disease, such as ostial/shaft LMCA disease, isolated LMCA disease (with or without one or two-vessel involvement), and LMCA disease with low SYNTAX score, PCI is an alternative, and in some cases a preferred, strategy to reduce surgical risks (eg, stroke and in-hospital events following major surgery). For the future, ongoing large clinical trials might also boost interventional cardiologists to select PCI with stenting as an alternative revascularization strategy for unprotected LMCA disease. This evidence will most likely change the current clinical practice and guidelines of optimal revascularization strategy for unprotected LMCA disease.

Downstream coronary effects of drug-eluting stents

BACKGROUND

Antiproliferative agents used in drug-eluting stents (DES) attenuate atherosclerosis, yet DES implantation has been linked to endothelial dysfunction. The downstream effects of DES on new lesion formation have not been previously directly examined. We sought to compare the development of de novo stenoses and need for treatment in the downstream coronary vessel of patients treated with DES or a bare-metal stent.

METHODS

Angiographic images and procedural information were prospectively collected on 463 adults who underwent implantation of a single stent in a proximal coronary artery, had an appropriate control vessel for comparison, and subsequently returned for intervention. Propensity matching identified 89 pairs of patients. End points were defined as angiographic identification of a de novo stenosis or need for secondary intervention in the downstream vessel within 12 months of initial intervention.

RESULTS

In the overall (P < .01) and propensity-matched cohort (P = .01), there was reduced risk of new lesions downstream to DES. No difference was seen in respective control vessels (P = .14 and P = .99). A reduced need for downstream intervention with DES was seen in both the overall (P = .01) and propensity-matched cohorts (P = .04). No difference was seen in the control vessels (P = .98 and P = .36). Multivariate proportional hazards modeling of known atherosclerosis risk factors identified stent type as the sole predictor for downstream lesions (P < .01) and downstream events (P = .02).

CONCLUSIONS

Patients receiving DES appear less likely to develop downstream stenoses and events compared with patients receiving bare-metal stents, suggesting beneficial downstream drug delivery.

Revascularization for unprotected left main coronary artery disease: an evolution in clinical decision making

Coronary artery bypass grafting (CABG) has been considered the standard therapy for unprotected (nonrevascularized) left main coronary disease (ULM). However, increasing experience with ULM percutaneous coronary intervention (PCI) has resulted in high procedural success and favorable early and late clinical outcomes. In particular, reduction in clinical restenosis with drug-eluting stents, evolution of procedural technique, and demonstration of favorable outcomes from comparative trials with CABG have promoted consideration of PCI as an alternative revascularization strategy in selected patients with ULM disease. This review summarizes the results from comparative studies examining PCI versus CABG for ULM disease, discusses changing indications for ULM PCI and identifies outstanding issues that must be considered before further advancing treatment recommendations.

Complexity of atherosclerotic coronary artery disease and long-term outcomes in patients with unprotected left main disease treated with drug-eluting stents or coronary artery bypass grafting

OBJECTIVES

The aim of this study was to compare treatment effects of drug-eluting stents (DES) or coronary artery bypass grafting (CABG) for left main coronary artery (LMCA) disease according to the complexity of atherosclerotic disease burden.

BACKGROUND

Limited information is available on the relationships between the extent of coronary atherosclerosis and very long-term outcomes of surgical or percutaneous LMCA revascularization.

METHODS

A total of 1,146 patients with unprotected LMCA disease who received DES (n = 645) or underwent CABG (n = 501) were evaluated. The extent of atherosclerotic disease burden was measured using the SYNTAX (Synergy Between PCI With Taxus and Cardiac Surgery) score; a low-risk score was defined as ≤ 22, an intermediate-risk score as 23 to 32, and a high-risk score as ≥ 33.

RESULTS

After multivariate adjustment with the inverse-probability-of-treatment weighting method, the 5-year risks for death (6.1% for DES vs. 16.2% for CABG; hazard ratio [HR]: 0.52; 95% confidence interval [CI]: 0.21 to 1.28; p = 0.15) and the composite of death, Q-wave myocardial infarction, or stroke (6.4% vs. 16.2%; HR: 0.54; 95% CI: 0.22 to 1.34; p = 0.18) favored DES in patients with low-risk SYNTAX scores; in contrast, the 5-year risks for death (26.9% vs. 17.8%; HR: 1.46; 95% CI: 0.92 to 2.30; p = 0.11) and the composite outcome (27.6% vs. 19.5%; HR: 1.36; 95% CI: 0.87 to 2.12; p = 0.18) favored CABG in patients with high-risk SYNTAX scores (interaction p = 0.047 for death, interaction p = 0.08 for composite outcome). Patients undergoing CABG consistently had lower rates of target vessel revascularization.

CONCLUSIONS

According to the complexity of concomitant coronary disease, there were differential treatment effects on long-term mortality in patients with unprotected LMCA disease who received DES or underwent CABG.

Revascularization of left main coronary artery disease

Coronary artery disease with left main stenosis is associated with the highest mortality of any coronary lesion. Studies in the 1970s and 1980s comparing coronary artery bypass grafting (CABG) and medical therapy showed a significant survival benefit with revascularization. In the angioplasty era, initial experience with percutaneous intervention was associated with poor clinical outcomes. As a result, percutaneous coronary intervention (PCI) was restricted to patients who were considered inoperable, or those with prior CABG with a functional graft to the left anterior descending or circumflex artery ("protected left main disease"). With the introduction of drug-eluting stents, there are new studies demonstrating comparable survival in patients who were revascularized using PCI and CABG, although percutaneous revascularization is associated with a higher rate of repeat revascularization. In the SYNTAX (Synergy between PCI with Taxus and Cardiac Surgery) trial, the combined incidence of death, myocardial infarction, and stroke was similar between the CABG and PCI groups; however, the stroke rate was higher in the CABG group. The degree and extent of disease as defined by the SYNTAX scoring system has allowed for stratification of risk and improved assignment of patients with left main stenosis to either PCI or CABG.