Spectrum of surgical risk for left main coronary stenoses: benchmark for potentially competing percutaneous therapies

Percutaneous Coronary Intervention vs. Coronary Artery Bypass Grafting in Left Main Coronary Artery Disease: An Updated Systematic Review and Meta-Analysis

Recently, both US and European guidelines have predominantly recommended coronary artery bypass grafting (CABG) as the preferred revascularisation method. However, emerging data have raised the possibility of percutaneous coronary intervention (PCI) being a viable and effective alternative. This meta-analysis sought to evaluate the latest insights from major clinical trials to ascertain whether PCI could be as effective as CABG in treating left main coronary artery (LMCA) disease. To achieve this, a comprehensive systematic search was conducted across databases, including Medline (via PubMed), Embase, Cochrane, and clinicaltrials.gov. The search spanned from the inception of these databases to August 20, 2022, and exclusively focused on randomized controlled trials (RCTs). Employing the random effects model, selected studies underwent rigorous analysis. The study outcomes encompassed a spectrum of factors such as all-cause mortality, major adverse cerebrovascular and cardiovascular events (MACCE), myocardial infarction (MI), stroke, and revascularisation procedures. The observation periods of interest included the 30-day mark, 1 year, 5 years, and 10 years. The analysis integrated six RCTs, revealing noteworthy patterns. In terms of all-cause mortality, PCI demonstrated non-inferiority to CABG across all observed time frames: 30 days (OR 0.6), 1 year (OR 0.77), 5 years (OR 1.41), and 10 years (OR 1.08). Analysis of MACCE outcomes favored PCI at 30 days and CABG at 5 years. The utilisation of the original five-year EXCEL (Evaluation of XIENCE versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularisation) trial definition for MI highlighted higher MI rates for PCI compared to CABG (OR 1.66, P < 0.05). Intriguingly, when the subsequently released EXCEL data, aligned with the third universal MI definition, was incorporated, the five-year data consistently leaned towards CABG. Specifically, the PCI group exhibited 7.5% MI rates in contrast to the 3.6% in the CABG cohort (OR 2.19, P < 0.001). Concerning stroke, PCI proved advantageous at 30 days and 1 year while exhibiting no significant disparity at 5 and 10 years. Revascularisation procedures favoured CABG at one and five years, with comparability at the remaining time points. In summation, the outcomes of this comprehensive meta-analysis suggest that PCI could serve as a feasible alternative to CABG in the context of uncomplicated LMCA disease. It's worth noting that CABG might still hold an advantage for complex lesions.

Percutaneous coronary intervention vs coronary artery bypass grafting for left main coronary artery disease? A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

It is not clear whether percutaneous coronary intervention (PCI) is as effective and safe as coronary artery bypass grafting (CABG) for left main coronary artery disease. We aimed to perform a systematic review and meta-analysis of all randomized controlled trials (RCTs) that compared PCI and CABG in left main coronary disease.

METHODS

We searched PubMed, EMBASE, Cochrane, Scopus and relevant references for RCTs (inception through, November 20, 2016 without language restrictions) and performed meta-analysis using random-effects model. All-cause mortality, myocardial infarction, revascularization rate, stroke, and major adverse cardiac and cerebrovascular events (MACCE) were the measured outcomes.

RESULTS

Six RCTs with a total population of 4700 were analyzed. There was no difference in all-cause mortality at 30-day, one-year, and five-year (1.8% vs 1.1%; OR 0.60; 95% CI: 0.26-1.39; P=.23; I² =9%) follow-up between PCI and CABG. CABG group had less myocardial infarction (MI) at five-year follow-up than PCI (5% vs 2.5%; OR 2.04; CI: 1.30-3.19; P=.002; I² =1%). Revascularization rate favored CABG in one-year (8.6% vs 4.5%; OR 2; CI: 1.46-2.73; P<.0001; I² =45%) and five-year (15.9% vs 9.9%; OR 1.73; CI: 1.36-2.20; P<.0001; I² =0%) follow-up. Although stroke rate was lower in PCI group at 1 year, there was no difference in longer follow-up. MACCE at 5 years favored CABG (24% vs 18%; OR 1.45; CI: 1.19-1.76; P=.0001; I² =0%). On subgroup analysis, MACCE were not different between two groups in low-to-intermediate SYNTAX group while it was higher for PCI group with high SYNTAX group.

CONCLUSION

Percutaneous coronary intervention could be as safe and effective as CABG in a select group of left main coronary artery disease patients.

Early outcome of Coronary Artery Bypass Graft Surgery in patients with significant Left Main Stem stenosis at a tertiary cardiac care center

Objective:

Primary objective of this study was to evaluate the impact of significant left main stem (LMS) stenosis on the early outcome of coronary artery bypass graft (CABG) surgery.

Methods:

A Retrospective non-randomized analytical study was conducted in Cardiac surgery department, Chaudhary Pervaiz Elahi Institute of Cardiology (CPEIC) Multan, Pakistan. The data of patients who underwent isolated CABG at our institution from February 2008 to March 2014 were analyzed. Two thousand six hundred two (2602) patients of isolated CABG were divided into 2 groups according to the LMS disease. Group I (n=2088): without significant LMS disease and Group II (n=514): with LMS disease. Data was analyzed using SPSS V16. The groups were compared using Student’s t-test for numeric variables. Chi-square test and Fishers Exact test were used for categorical variables. P-value ≤ 0.05 was considered as significant difference.

Results:

Out of two thousand six hundred two, 2088 patients were in Non.LMS group (Control Group) and five hundred fourteen were in LMS Group (Study Group). Patients with LMS disease were older. In both groups there was no statistically significant difference regarding gender distribution, risk factors of IHD, pre-operative renal function and preoperative CKMB levels. Significant number 50 (9.7%) of patients were unstable in LMS group and they needed urgent surgery (p-value <0.0001). Need and duration for inotropic support and intra-aortic balloon counter-pulsation support were significantly high in LMS group (p-value <0.0001, 0.002, 0.003 respectively). Similarly Mechanical ventilation time and hospital stay were higher in LMS group. Incidence of pulmonary complications and operative mortality were significantly higher in LMS group (p-value 0.005 and 0.001 respectively). Mortality of CABG patients with significant left main coronary stenosis was 13 out of five hundred fourteen (2.5%) as compared to just 17 out of two thousand eighty eight (0.8%) in control group.

Conclusion:

This study showed that significant LMS disease is an independent risk factor for early cardiopulmonary morbidity and mortality after CABG surgery.

Invasive assessment modalities of unprotected left main stenosis

Among all coronary lesions, the decision-making process for the treatment of unprotected left main (ULM) stem lesions is still challenging. Indeed, the optimal therapeutic strategy for patients with ULM disease remains controversial: coronary artery bypass grafting was established as the gold standard, but it is without doubt that percutaneous coronary intervention (PCI) performed by experienced operators achieves good results at long term follow up, especially in cases where the ostium and/or shaft of ULM are treated. Thanks to the widespread use of invasive assessment of atherothrombotic ULM stenosis, improved selection of PCI cases and techniques of stenting, better outcomes are now possible. This review seeks to define the place of PCI in ULM disease by describing the different modalities of ULM stenosis assessment.

Dual protection therapy with staged coronary artery bypass surgery and stenting in patients with left main coronary artery stenosis: long-term results from a single center

OBJECTIVE

We evaluated the efficacy and safety of dual protection therapy with staged coronary artery bypass grafting (CABG) and bare-metal stenting (BMS) in patients with left main coronary artery (LMCA) disease.

BACKGROUND

CABG is currently the preferred therapy for complex LMCA disease; however, the long-term patency rates of these grafts are unsatisfactory, and stenting alone for LMCA may be associated with the potentially fatal consequences of stent thrombosis or restenosis.

METHODS

Between January 1997 and October 2005, 42 patients underwent staged bypass surgery and BMS, with the latter procedure performed 2 weeks after the initial CABG. Of these patients, 40 received left internal mammary artery (LIMA) grafts, 34 saphenous vein grafts, 6 radial artery grafts, and 3 right IMA (RIMA) grafts. Minimally invasive bypass surgery was performed in 10 patients.

RESULTS

There were no operative complications. Forty-two stents were implanted in 42 lesions without complications. During the follow-up period of 135 ± 55 months, 1 patient died of cancer, 2 of cardiac causes, and 5 patients (12%) experienced target lesion revascularization. The target vessel failure rate was 24%. Forty patients (95%) underwent a 6-month angiographic follow-up. Restenosis was noted in 7 patients (18%). Reocclusion was also noted in 5 LIMA grafts, 5 saphenous vein grafts, 1 radial artery graft, and 1 RIMA graft. Only 1 patient experienced both restenosis of LM stenting and total occlusion of the 2 bypass grafts.

CONCLUSIONS

Dual protection therapy with staged CABG and stenting is not an appropriate therapeutic strategy because of unacceptable graft patency rate. A higher occlusive rate of the bypass grafts may result from decreased blood flow because of competing blood flow between the bypass graft and the native coronary vessel.

Long-term clinical outcomes after unprotected left main coronary artery stenting in an all-comers patient population

BACKGROUND

The goal of treating patients with coronary artery disease is to improve survival and relieve symptoms. Several studies have compared the safety and efficacy of left main coronary artery (LMCA) stenting and coronary-artery bypass grafting in case control and randomized trials.

OBJECTIVE

In this study we present the long term outcome of stenting unprotected LMCA stenosis in day to day practice in unselected patients.

METHODS

One hundred and fifty eight patients were prospectively recruited with symptomatic unprotected LMCA stenosis undergoing percutaneous coronary intervention (PCI). Using the euroSCORE, each patient's surgical mortality risk was estimated. Study end-points were any major adverse cardiac event (MACE) defined as cardiac death, nonfatal myocardial infarction, or target lesion revascularization at follow-up with either CABG or repeat PCI.

RESULTS

The mean follow-up was 54 ± 25 months. The mean euroSCORE was 10.6 ± 13.4 (0.9-71) and the mean SYNTAX score was 39.6 ± 10.7 (10-65). The MACE rate was 11.4% at a mean follow up of 54 months. Six (3.8%) patients suffered postprocedure myocardial infarction. There were 24 (15%) deaths of which 12 were cardiac (mean euroSCORE 21.6 ± 5.5 P < 0.001). Repeat angiography was performed in 88 (55.7%) patients. Seven (4.4%) patients had in-stent restenosis; three occurred in BMS (P = 0.06). Two patients underwent revascularization with CABG and five had successful repeat PCI.

CONCLUSION

In this on-going registry of high risk patients with LMCA stenosis, stenting was found to be safe and clinically effective in maintaining event-free survival.

Unprotected left main coronary stenting as alternative therapy to coronary bypass surgery in high surgical risk acute coronary syndrome patients

Acute coronary syndrome has a high mortality rate that dramatically increases in the presence of left main coronary artery (LMCA) disease. Over the past decades, coronary artery bypass graft (CABG) surgery has been commonly accepted as the standard of care for patients with LMCA stenosis and is still considered the first-line treatment in current practice guidelines. Percutaneous coronary intervention (PCI) of protected and unprotected LMCA has gained popularity and is increasingly utilized with comparable outcomes to CABG in randomized controlled trials. In-stent restenosis and the need for revascularization provide the main obstacle to LMCA revascularization. The advent of better PCI equipment, stents, ablative devices, intravascular ultrasound, hemodynamic support devices and antithrombotic agents have ignited a renewed interest in the practice of LMCA PCI, especially for high surgical risk patients who are neither candidates nor agreeable to CABG surgery. Herein, we review the studies comparing unprotected LMCA stenting with CABG surgery in regard to 3 main endpoints: mortality, major adverse events and the incidence of repeat revascularization.

Similar survival 15 years after coronary artery surgery irrespective of left main stem stenosis

OBJECTIVES

To evaluate 15-year survival after coronary artery bypass grafting (CABG) in relation to grade left main stenosis (LMS) and right coronary artery (RCA) obstruction.

DESIGN

Coronary angiographic findings were prospectively collected in 977 patients who had CABG for stable angina during 1994-1995 and were included in the Swedish Coronary Revascularization - Swedish Council of Technology Assessment study.

RESULTS

Significant LMS was present in one fifth of the patients and significant RCA obstruction was found in 61% of those with LMS and in 68% of patients without LMS. The patients were categorized as no LMS (Group I), LMS without RCA obstruction (Group II) or significant LMS with significant right coronary artery (RCA) obstruction (Group III). Early mortality did not differ in the three groups and was 1.2, 1.2% and 0.8% in group I, II and III, respectively. Corresponding survival at 15 years was similar 51%, 47% and 47%, respectively. In multivariable analysis older age, smoking, severe angina, positive stress test, hypertension, diabetes mellitus and ejection fraction < 50% were risk factors for death at 15 years.

CONCLUSIONS

Death 15 years after CABG correlated to clinical variables but was not predicted from presence of LMS with or without significant associated RCA obstruction.

Comparison of outcomes of unprotected left main versus multivessel coronary artery interventions

Left main coronary artery (LMCA) percutaneous coronary intervention (PCI) has emerged as an appealing alternative to bypass surgery for significant LMCA disease, especially in high-risk candidates. PCI for unprotected LMCA stenosis is currently designated a class IIb indication. Direct comparisons between unprotected LMCA PCI and multivessel PCI are lacking. We aimed to determine the incremental risk associated with unprotected LMCA PCI compared to multivessel PCI. We queried the Cleveland Clinic PCI database to identify patients who underwent unprotected LMCA PCI from 2003 through 2009 and compared these to patients undergoing multivessel PCI in the same period. Patients undergoing PCI for acute myocardial infarction were excluded. Mortality was derived using the Social Security Death Index. Short-term (≤30-day) mortality rates in the LMCA PCI group (n = 468, 1.9%) were similar to the death rate in the multivessel PCI group (n = 1,973, 1.3%, p = 0.3). There was no significant difference in adjusted mortality between the 2 study groups. Stratifying LMCA PCI by the number of concomitant vessel territories treated, there was no significant difference in mortality in any LMCA PCI category (LMCA only, LMCA + 1-vessel PCI, LMCA + multivessel PCI) compared to multivessel PCI. In conclusion, there was comparable short-term and long-term mortality in the LMCA PCI and multivessel PCI groups. LMCA stenting did not appear to incur incremental risk compared to multivessel PCI.

Ostial left main coronary artery stenosis as an additional risk factor in off-pump coronary artery bypass grafting

BACKGROUND

Our aim was to determine whether general left main coronary artery stenosis (LMS) and ostial LMS pose additional risks after off-pump coronary artery bypass grafting (CABG) relative to non-left main coronary artery stenosis.

METHODS

From January 1, 2008, to December 31, 2009, 4366 patients underwent primary isolated off-pump CABG at Beijing Anzhen Hospital. Disease was retrospectively classified as non-left main disease (n = 3523), nonostial LMS (n = 765), and ostial LMS (n = 78). Groups were propensity score matched. Kaplan-Meier freedoms from major adverse cardiac and cerebrovascular events (MACCEs) were calculated.

RESULTS

During the first 30 postoperative days, mortality was significantly higher in the ostial LMS group (6.41%) than in non-left main disease (0.855%, χ(2) = 7.78, P = .005) and nonostial LMS (1.28%, χ(2) = 4.71, P = .03) groups. Incidence of MACCEs was significantly higher in the ostial LMS group (20.5%) than in non-left main disease (5.98%, P = .000) and nonostial LMS (9.62%, P = .002) groups. Odds ratio for early MACCEs of ostial LMS versus non-left main disease was 3.74 (95% confidence interval, 1.72-8.17). At mean follow-up 12.8 ± 7.5 months and cumulative follow-up 498.5 patient-years, difference among groups in freedom from MACCEs did not reach statistical significance (χ(2) = 2.39, P = .303).

CONCLUSIONS

Ostial LMS poses additional early risks of mortality and MACCEs in off-pump CABG. Off-pump CABG for ostial LMS should proceed with greater of intraoperative surveillance and lower threshold for converting to on-pump CABG.

Predictors of improvement in left ventricular function after initially successful angioplasty of unprotected left main coronary artery stenoses

BACKGROUND

Percutaneous coronary intervention (PCI) has been increasingly applied to unprotected left main coronary artery (LMCA) lesions, with varied procedural success and clinical outcomes. However, the effect of PCI on left ventricular performance is still unclear, and there are no clinical studies assessing factors that influence left ventricular ejection fraction (LVEF) in these cases.

METHODS

Between April 1986 and August 2002, de novo PCI was performed for unprotected LMCA stenoses in 199 patients. Close clinical and angiographic follow-up were conducted after the procedure.

RESULTS

One hundred eighty patients survived over six months and analysis of paired left ventriculography was possible in 175 patients. Improvement in LVEF was observed in the entire population (52.9 +/- 15.7% to 56.1 +/- 14.3%, p = 0.048). The LVEF change was 6.7 +/- 9.5% (p < 0.01) in group with baseline LVEF < or = 50% and 0.7 +/- 6.7 % (p = NS) in group with LVEF > 50%. There was significant intergroup difference (p < 0.001). Patients with baseline diameter stenosis > or = 60% had an improvement of 5.3 +/- 8.3% (p < 0.05) whereas those with stenosis < 60% had no improvement (2.0 +/- 8.4%, p = NS). CK-MB elevation > or = 3 times normal after PCI had a significant inverse association with improvement in LVEF (p < 0.05). Multivariate analysis revealed baseline LVEF < or = 50% was the only independent predictor of improvement in LVEF (standard estimate = 3.509, 95% CI: 2.164-4.854, p < 0.001).

CONCLUSIONS

Successful PCI procedure is associated with significant improvement in LVEF, especially in patients with depressed left ventricular function.

Coronary angioplasty in drug eluting stent era for the treatment of unprotected left main stenosis compared to coronary artery bypass grafting

BACKGROUND

Improved outcomes of percutaneous coronary interventions (PCI) with drug-eluting stents (DES) have resulted in their expanded use for left main coronary artery (LMCA) stenosis.

AIM

We compared outcomes of patients undergoing PCI for unprotected LMCA stenosis and patients treated by coronary artery bypass grafting (CABG).

METHOD

Between January 2005 and January 2007, 6705 patients were studied with coronary angiography in northern Finland. All subjects treated with revascularization of LMCA stenosis (n = 287) were included and followed up for a mean of 12+6 months.

RESULTS

From 287 patients, 238 underwent CABG, and 49 had PCI with DES. The incidence of 1-year mortality was 4% among the PCI-treated and 11% among CABG-treated patients (P = 0.136). After the first month, mortality among PCI-or CABG-treated patients did not differ statistically significantly (2% versus 7%, P = 0.133). The most significant independent predictor of mortality was reduced left ventricular systolic function (hazard ratio 14.9, 95% CI 5.5-40.0, P < 0.001).

CONCLUSIONS

PCI with DES for selected LMCA disease patients results in short- and midterm outcomes comparable to results of CABG in general. PCI is a viable therapeutic option in selected patients with LMCA stenosis.

A Benchmark for Evaluating Innovative Treatment of Left Main Coronary Disease

BACKGROUND

Left main trunk stenosis (> or = 50%) has traditionally been treated with coronary artery bypass grafting. Improvements in coronary stents have led some to advocate percutaneous coronary intervention. To provide a benchmark of outcomes against which percutaneous coronary intervention may be compared, we (1) assessed survival and freedom from coronary reintervention after coronary artery bypass grafting in these patients and (2) identified their risk factors.

METHODS AND RESULTS

From 1971 to 1998, the first 1000 primary coronary artery bypass grafting patients (n=26,927) were followed every 5 years. Of these, 3803 had left main trunk stenosis > or = 50%. A multivariable, nonproportional hazards, time-related analysis was performed to model survival and freedom from coronary reintervention (percutaneous coronary intervention or reoperation) and to identify their risk factors. Survival at 30 days, 1, 5, 10, 15, and 20 years was 97.6%, 93.6%, 83%, 64%, 44%, and 28%, respectively, and freedom from coronary reintervention was 99.7%, 98.9%, 96.6%, 89%, 76%, and 61%, respectively. Worse left ventricular function (P<0.0001), diabetes (P<0.0001), hypertension (P<0.001), peripheral arterial disease (P=0.0002), smoking (P<0.0001), and elevated triglycerides (P=0.01) decreased survival, and younger age (P<0.0001), elevated triglycerides (P=0.005), and incomplete revascularization (P=0.003) increased coronary reintervention. Internal thoracic artery grafting of the left anterior descending improved survival and decreased coronary reintervention.

CONCLUSIONS

This study provides a 20-year outcome benchmark for surgical treatment of left main trunk disease. It indicates that simple comparisons of new treatments are inadequate without risk adjustment. Risk factor adjustment should be used when comparing coronary artery bypass grafting with current and future treatment innovations and when selecting the best treatment strategy for individual patients.

Left main coronary artery stenosis: state-of-the-art

Patients with stenosis of the left main coronary artery present difficult challenges. The risks associated with this lesion have been known since the early days of angiography when patients were found to have increased mortality during follow-up. This information led to the general guidelines that surgical revascularization should be considered the treatment of choice in patients with significant left main coronary artery stenosis. Current advances in invasive cardiology have brought important information to the field. Intravascular ultrasound is now used routinely to evaluate angiographically indeterminate lesions with criteria now set forward as to what constitutes an indication for revascularization. Stents have even further dramatically changed the landscape. There are substantial issues, however, that need to addressed. These include the following: (1) the effect of specific lesion location on outcome - it is known that patients with distal bifurcation left main disease have worse outcome; (2) the potential for subacute thrombosis of the left main coronary artery; (3) the impact of left ventricular function and patient comorbidities irrespective of the degree and location of left main coronary artery stenosis; and (4) the risk-benefit ratio of stenting versus coronary artery bypass graft surgery. These issues are currently being addressed in two seminally important trials including the SYNTAX trial, which randomizes patients with left main and/or three-vessel disease to either coronary artery bypass graft surgery or a TAXUS drug-eluting stent. This trial is in the final stages of patient recruitment and will have important implications for the field. The other trial is the COMBAT trial, which is focused exclusively on left main coronary artery stenosis and randomizes patients with left main coronary artery disease either to a Sirolimus-eluting stent (Cypher, Johnson and Johnson Cordis, USA) or to coronary artery bypass graft surgery. The field of left main coronary artery disease continues to expand in terms of the evidence available for optimal patient evaluation and selection of treatment modalities.

Predictors of long-term outcomes in patients after elective stent implantation for unprotected left main coronary artery disease

The purpose of this study was to investigate the predictor of long-term outcomes in patients after stent implantation for unprotected left main coronary artery (LMCA) disease. Coronary stenting has recently been advocated as an alternative procedure for LMCA disease. Information on the predictors of long-term outcomes in patients after stent implantation for unprotected LMCA disease is not clear. Seventy six patients (51 men and 25 women, age 68 +/- 10 years) with medically refractory angina received coronary stenting for unprotected LMCA disease. During a follow-up period of 40 +/- 26 months, 7 patients (9%) died because of cardiovascular disease in 5 (7%) and noncardiovascular disease in 2 (3%). In the other 69 patients, 19 patients (25%) needed repeated percutaneous coronary intervention (PCI) and/or coronary artery bypass grafting (CABG). In a univariate analysis, only female sex was related to the repeated PCI and/or CABG (P = 0.04). A history of cerebral vascular attack (CVA) (P = 0.005), anemia (P = 0.03) and lower left ventricular ejection fraction (LVEF) (P = 0.008) were related to the cardiovascular mortality. A history of myocardial infarction (P = 0.03), a history of CVA (P = 0.02), anemia (P = 0.02), and lower LVEF (P = 0.002) were related to the total mortality. In a multivariate analysis, female sex (P = 0.007; odds ratio 5.29, 95% confidence interval [CI] 1.57-17.80) and young age (P = 0.025; odds ratio 3.92, 95% CI 1.19-12.98) could predict the repeated PCI and/or CABG. Only a history of CVA could predict the cardiovascular mortality (P = 0.027; odds ratio 34.18, 95% CI 1.49-783) and only lower LVEF could predict the total mortality (P = 0.027; odds ratio 13.26, 95% CI 1.34-131). Female sex and young age could predict the repeated PCI and/or CABG in patients after stent implantation for unprotected LMCA disease. Furthermore, a history of CVA could predict the cardiovascular mortality and lower LVEF could predict the total mortality.

Left main coronary artery thrombectomy and stenting using a paclitaxel-eluting stent in the setting of acute myocardial infarction

A 41-year-old man was referred to the Montreal Heart Institute, Montreal, Quebec, for primary angioplasty of an acute anterolateral wall myocardial infarction. Coronary angiography revealed the culprit lesion to be a subtotal left main coronary artery with Thrombolysis In Myocardial Infarction (TIMI) trial grade 1 flow associated with a filling defect compatible with an aggressive thrombotic process. The use of rheolytic thrombectomy and a drug-eluting stent for this distal left main target lesion are described.

Comparison between coronary angioplasty and coronary artery bypass surgery for the treatment of unprotected left main coronary artery stenosis (the Bologna Registry)

Although great interest exists in the relative efficacy of coronary artery bypass grafting (CABG) versus percutaneous coronary intervention (PCI) for the treatment of unprotected left main coronary artery stenosis, data comparing the 2 strategies are scant. Furthermore, no comparison has ever been performed between CABG and drug-eluting stents in this setting. From January 2002 to June 2005, 154 patients with unprotected left main coronary artery stenosis underwent CABG and 157 underwent PCI. Ninety-four patients received a drug-eluting stent in the left main artery. After a median follow-up of 430 days, the rate of mortality, acute myocardial infarction, and target lesion revascularization was 12.3%, 4.5%, and 2.6%, respectively, in the CABG group and 13.4%, 8.3%, and 25.5%, respectively, in the PCI group (death and myocardial infarction p = NS, target lesion revascularization p = 0.0001). Although patients treated with drug-eluting stents had a 25% relative risk reduction in the rate of death, myocardial infarction, and target lesion revascularization compared with patients treated with bare stents, event-free survival was still better for patients treated with CABG. In the multivariate analysis, age >or=70 years, New York Heart Association classes III and IV, acute coronary syndromes, and peripheral vascular disease were the only independent predictors of mortality. In conclusion, our results have indicated that at long-term follow-up no difference exists in the rate of mortality and myocardial infarction between PCI and CABG for the treatment of unprotected left main coronary artery stenosis. However, the rate of target lesion revascularization was higher in the PCI group.

Comparison of Coronary Artery Bypass Surgery With Percutaneous Coronary Intervention With Drug-Eluting Stents for Unprotected Left Main Coronary Artery Disease

OBJECTIVES

This study evaluated the clinical outcomes of consecutive, selected patients treated with coronary artery bypass graft (CABG) surgery or percutaneous coronary intervention (PCI) with drug-eluting stents (DES) for unprotected left main coronary artery (ULMCA) disease.

BACKGROUND

Although recent data suggest that PCI with DES provides better clinical outcomes compared to bare-metal stenting for ULMCA disease, there is a paucity of data comparing PCI with DES to CABG.

METHODS

Since April 2003, when DES first became available at our institution, 123 patients underwent CABG, and 50 patients underwent PCI with DES for ULMCA disease.

RESULTS

High-risk patients (Parsonnet score >15) comprised 46% of the CABG group and 64% of the PCI group (p = 0.04). The 30-day major adverse cardiac and cerebrovascular event (MACCE) rate for CABG and PCI was 17% and 2% (p < 0.01), respectively. The mean follow-up was 6.7 +/- 6.2 months in the CABG group and 5.6 +/- 3.9 months in the PCI group (p = 0.26). The estimated MACCE-free survival at six months and one year was 83% and 75% in the CABG group versus 89% and 83% in the PCI group (p = 0.20). By multivariable Cox regression, Parsonnet score, diabetes, and CABG were independent predictors of MACCE.

CONCLUSIONS

Despite a higher percentage of high-risk patients, PCI with DES for ULMCA disease was not associated with an increase in immediate or medium-term complications compared with CABG. Our data suggest that a randomized comparison between the two revascularization strategies for ULMCA may be warranted.

Technique of left main stenting is dependent on lesion location and distal branch protection

The purpose of this study was to review our experience with left main stenting and evaluate initial results with drug-eluting stents (DESs). Drug-eluting stents delivered with contemporary techniques could change the traditional surgical approach to patients with significant left main disease. One hundred sixty-one patients underwent left main stenting (100 bare metal, 61 drug-eluting) after being excluded from surgery. In group A, disease was confined to the ostium or main stem; in group B, disease involved the bifurcation. Patients were classified as either unprotected (U) or protected (P) depending on the presence of a patent bypass graft. Study endpoints were any major adverse cardiac event (MACE). In-hospital MACE was 6% with no deaths; 74% of patients in group A underwent direct stenting, whereas 89% of the patients in group B had predilatation performed prior to stent implantation. A total of 98% of patients in BU had kissing balloon inflations after stent deployment; provisional side-branch stenting was required in one patient. V-stenting was performed in 13% of patients in group BU. The 1-year mortality in the bare metal stent group was 9% with the majority of deaths in group BU. There was one noncardiac death in the DES group at 6 months and five patients (8.2%) underwent target vessel revascularization for restenosis. Event-free survival at 6 months in group BU treated with DESs was 87%. Significant left main disease presents a spectrum of angiographic abnormalities and different interventional techniques are required depending on lesion location and distal protection. Although in-hospital complications with left main stenting were low in this single-center study, follow-up events were common in patients treated with bare metal stents. A randomized multicenter trial will be required to determine whether drug-eluting stents will improve survival in patients with left main disease.

Percutaneous intervention of unprotected left main coronary artery

Successful percutaneous intervention of unprotected left main coronary artery (LMCA) in lieu of surgical revascularization represents the next wave of challenges that the field of interventional cardiology will try to overcome. Significant LMCA stenosis, commonly secondary to atherosclerosis, is seen in about 4-10% of cases presenting to the cardiac catheterization laboratory. Currently, the vast majority of these patients undergo surgical revascularization unless there are prohibitive reasons for surgical revascularization. Several challenges of percutaneous revascularization have been overcome with stents, intravascular brachytherapy, and other technical improvements. Yet, several remaining limitations of percutaneous intervention, such as in-stent restenosis, have to be improved further before randomized clinical trials of surgical and percutaneous revascularization of unprotected LMCA disease can be contemplated to establish a new standard of care.

Long-term (three-year) outcomes after stenting of unprotected left main coronary artery stenosis in patients with normal left ventricular function

The purpose of this study was to analyze long-term follow-up information from patients treated with stenting for unprotected left main coronary artery (LMCA) stenosis. Stenting of unprotected LMCA stenosis is often performed in selected patients, but the long-term safety of this therapy is not yet established. Between January 1995 and September 2000, 270 consecutive patients with unprotected LMCA stenosis and normal left ventricular function who underwent treatment at 4 clinical centers were included in this study. Data were forwarded to the coordinating center using a standard case report form. The procedural success rate was 98.9%. There were no deaths, 3 stent thromboses, and 3 Q-wave myocardial infarctions during the hospitalization. Angiographic follow-up was performed in 237 patients (follow-up rate 87.8%), and the restenosis rate was 21.1%. The reference size was an independent predictor of binary restenosis (odds ratio 0.543, 95% confidence interval 0.308 to 0.957, p = 0.03). During the follow-up period (32.3 +/- 18.5 months), there were 20 deaths (8 cardiac, 12 noncardiac) and 5 nonfatal myocardial infarctions. Target and new lesion revascularizations were required in 45 (16.7%) and 31 (11.5%) patients, respectively. The cumulative probabilities free from major adverse cardiac events were 81.9 +/- 2.4%, 78.4 +/- 2.6%, and 77.7 +/- 2.7%, respectively, at 1, 2, and 3 years. Combined coronary artery disease and postprocedural minimal luminal diameter were the significant predictors of major adverse cardiac events. Thus, the long-term prognosis of patients after stenting of unprotected LMCA stenosis was favorable in selected patients with normal left ventricular function.

Percutaneous reperfusion of left main coronary disease complicated by acute myocardial infarction

Previous studies have shown a benefit of a strategy of direct angioplasty and stenting in patients with acute myocardial infarction (AMI) complicated by early cardiogenic shock. However, few data exist for the subset of patients with left main trunk disease complicated by AMI and cardiogenic shock. We performed an analysis of patients with AMI who underwent mechanical intervention between January 1995 and December 2000. Out of 1,433 patients with ST segment elevation AMI treated with primary coronary angioplasty (PTCA), 22 patients (1.5%) had left main disease (LMD) as the culprit lesion. Baseline characteristics were age, 66 +/- 11 years; female gender, 9%; diabetes, 14%; previous myocardial infarction, 14%; mean systolic blood pressure, 77 +/- 24 mm Hg; time to treatment, 4.8 +/- 2.2 hr; TIMI 0-1, 77%; collateral flow (Rentrop grade >or= 2) 9%. The primary success rate was 91%. Primary stenting was performed in 17 patients (77%). The in-hospital mortality rate was 50%. All deaths were due to refractory shock. The 6-month survival rate was 41% +/- 1%, while the event-free survival rate was 27% +/- 10%. At 6-month follow-up, the mortality rate increased to 59%; the target vessel revascularization rate was 14%. A percutaneous mechanical intervention strategy in patients with left main disease complicated by AMI is feasible and effective, and patients discharged alive have a good mid-term prognosis.

Long-term clinical outcomes after unprotected left main trunk percutaneous revascularization in 279 patients

BACKGROUND

Percutaneous coronary revascularization (PCI) has been increasingly applied to unprotected left main trunk (LMT) lesions, with varied long-term success. This study attempts to define the predictors of outcome in this population.

METHODS AND RESULTS

Two hundred seventy-nine consecutive patients who had LMT PCI at 1 of 25 sites between 1993 and 1998 were studied. Forty-six percent of these patients were deemed inoperable or at high surgical risk. Thirty-eight patients (13.7%) died in hospital, and the rest were followed up for a mean of 19 months. The 1-year incidence was 24.2% for all-cause mortality, 20.2% for cardiac mortality, 9.8% for myocardial infarction, and 9.4% for CABG. Independent correlates of all-cause mortality were left ventricular ejection fraction </=30%, mitral regurgitation grade 3 or 4, presentation with myocardial infarction and shock, creatinine >/=2.0 mg/dL, and severe lesion calcification. For the 32% of patients <65 years old with left ventricular ejection fraction >30% and without shock, the prevalence of these adverse risk factors was low. No periprocedural deaths were observed in this low-risk subset, and the 1-year mortality was only 3.4%.

CONCLUSIONS

Patients undergoing unprotected LMT PCI have frequent serious comorbidities and consequently have high event rates. PCI may be an alternative to CABG for a select proportion of elective patients and may also be appropriate for highly symptomatic inoperable patients. Meticulous follow-up of hospital survivors is required because of the rather high mortality during the first few months after treatment.

Elective stenting of unprotected left main coronary artery stenosis: effect of debulking before stenting and intravascular ultrasound guidance

OBJECTIVES

We sought to evaluate: 1) the long-term outcomes of 127 selected patients receiving unprotected left main coronary artery (LMCA) stenting; and 2) the impact of the debulking procedure before stenting and intravascular ultrasound (IVUS) guidance on their clinical outcomes.

BACKGROUND

The long-term safety of stenting of unprotected LMCA stenoses has not been established yet.

METHODS

A total of 127 consecutive patients with unprotected LMCA stenosis and normal left ventricular function were treated by elective stenting. The long-term outcomes were evaluated between two groups: IVUS guidance (n = 77) vs. angiographic guidance (n = 50); and debulking plus stenting (debulking/stenting; n = 40) vs. stenting only (n = 87).

RESULTS

Angiographic restenosis was documented in 19 (19%) of 100 patients. The lumen diameter after stenting was significantly larger in IVUS-guided group (p = 0.003). The angiographic restenosis rate was significantly lower in the debulking/stenting group (8.3% vs. 25%, p = 0.034). The reference artery size was the only independent predictor of angiographic restenosis. During follow-up (25.5 +/- 16.7 months), there were four deaths, but no nonfatal myocardial infarctions occurred. The survival rate was 97.0 +/- 1.7% at two years.

CONCLUSIONS

These data suggest that stenting of unprotected LMCA stenosis might be associated with a favorable long-term outcome in selected patients. Guidance with IVUS may optimize the immediate results, and debulking before stenting seems to be effective in reducing the restenosis rate. However, we need a large-scale, randomized study.

Initial and long-term results of directional coronary atherectomy in unprotected left main coronary artery

Angioplasty in the unprotected left main coronary artery (LMCA) has been controversial. Recently, several studies have suggested that new procedures and devices such as directional coronary atherectomy (DCA) and stents may change this situation. Although there are many reports of unprotected LMCA stenting, there are few reports of DCA of this lesion. Therefore, initial and long-term results were evaluated in 101 patients who underwent DCA for unprotected LMCA in our hospital. Emergency procedures were performed in 15 patients and electively in 86 patients. Scheduled angiographic follow-up was routinely performed, and all patients were clinically followed for >4 months after DCA. Technical success was achieved in 99%, and in-hospital outcomes were cardiac death (2%), noncardiac death (4%), Q-wave myocardial infarction (1%), non-Q-wave myocardial infarction (8.9%), coronary artery bypass grafting (0%), and repeat angioplasty (4%). In-hospital results varied considerably, depending on presentation. In-hospital mortality was significantly higher in the emergency, left ventricular ejection fraction < or =35%, and high-risk surgical subgroups. The angiographic restenosis rate was 20.4% at follow-up, and its predictor was postminimal lumen diameter by multivariate analysis. Mean clinical follow-up was 2.8 years; estimated 1- and 3-year survival rates were 87% and 80.7%, respectively. The cardiac survival rate of the low-risk surgical subgroup was significantly higher than that of the high-risk surgical subgroup (p <0.05). Thus, our data show that DCA can be performed safely and effectively in unprotected LMCA with an acceptable low restenosis rate and high survival rate.

Does unprotected left main-stem stenting have a role in current interventional practice?

Left main-stem disease is found in up to 5% of patients undergoing coronary angiography. Until recently, it has been regarded as an absolute indication for coronary bypass surgery, given the poor results of the early trials of balloon angioplasty for this condition. However, with rapidly advancing technology, including new generation stents and increasingly effective post-stenting anti-thrombotic regimens, there is now an increasing body of evidence to support the consideration of a percutaneous approach to left main-stem disease. Discerning patient selection, meticulous stent sizing and deployment, the routine use of intravascular ultrasound, aggressive anti-platelet regimes, and careful patient follow up are a few of the technical considerations required for a successful long-term outcome in this group.

Initial and long-term results of angioplasty in unprotected left main coronary artery

Angioplasty of the unprotected left main coronary artery (LMCA) has been controversial. Although recent single-center studies suggest that new devices may change the situation, many questions and problems remain. Therefore, the results of unprotected left main coronary angioplasty of 175 procedures in 107 patients were analyzed to evaluate its feasibility and effectiveness. The treatment of the initial 107 cases included balloon angioplasty (39 cases, 36%), directional coronary atherectomy (53 cases, 50%), and stents (15 cases, 14%). They were divided into 3 major subgroups: (1) acute group (n = 14), in which LMCA angioplasty was performed in patients with acute myocardial infarction; (2) emergency group (n = 10); and (3) elective group (n = 83). In-hospital mortality was higher in the acute (35.7%) and emergency (40.0%) groups than in the elective group (3.6%; p <0.0001). Angiographic follow-up was routinely performed and the restenosis rate including in-hospital restenosis was 70% in the acute group, 37.5% in the emergency group, and 40% in the elective group (p = NS). The mean clinical follow-up period was 2.9 years, and the estimated 5-year survival rates of the acute and emergency groups were 50% and 48.2%, respectively. However the 5-year survival rate of the elective group was higher than that seen in the acute or emergency group (77.5%; p <0.05). Repeat LMCA angioplasty was performed in 37 of 68 patients with 8.8% mortality (38.5% of acute and emergency cases and 1.8% of elective cases). The results indicated that elective unprotected LMCA angioplasty is relatively feasible and effective under scheduled angiographic follow-up.