Stenting of unprotected left main coronary artery stenoses: immediate and late outcomes

Percutaneous Coronary Intervention Versus Coronary Artery Bypass Grafting for Revascularization of Left Main Coronary Artery Disease

Owing to a large-jeopardized myocardium, left main coronary artery disease (LMCAD) represents the substantial high-risk anatomical subset of obstructive coronary artery disease. For several decades, coronary artery bypass grafting (CABG) has been the "gold standard" treatment for LMCAD. Along with advances in CABG, percutaneous coronary intervention (PCI) has also dramatically evolved over time in conjunction with advances in the stent or device technology, adjunct pharmacotherapy, accumulated experiences, and practice changes, establishing its position as a safe, reasonable treatment option for such a complex disease. Until recently, several randomized clinical trials, meta-analyses, and observational registries comparing PCI and CABG for LMCAD have shown comparable long-term survival with tradeoffs between early and late risk-benefit of each treatment. Despite this, there are still several unmet issues for revascularization strategy and management for LMCAD. This review article summarized updated knowledge on evolution and clinical evidence on the treatment of LMCAD, with a focus on the comparison of state-of-the-art PCI with CABG.

Percutaneous Coronary Intervention for Left Main Coronary Artery Disease: Present Status and Future Perspectives

For several decades, coronary artery bypass grafting has been regarded as the standard choice of revascularization for significant left main coronary artery (LMCA) disease. However, in conjunction with remarkable advancement of device technology and adjunctive pharmacology, percutaneous coronary intervention (PCI) offers a more expeditious approach with rapid recovery and is a safe and effective alternative in appropriately selected patients with LMCA disease. Several landmark randomized clinical trials showed that PCI with drug-eluting stents for LMCA disease is a safe option with similar long-term survival rates to coronary artery bypass grafting surgery, especially in those with low and intermediate anatomic risk. Although it is expected that the updated evidence from recent randomized clinical trials will determine the next guidelines for the foreseeable future, there are still unresolved and unmet issues of LMCA revascularization and PCI strategy. This paper provides a comprehensive review on the evolution and an update on the management of LMCA disease.

Long-Term Clinical Impact of Intravascular Ultrasound Guidance in Stenting for Left Main Coronary Artery Disease

[Figure: see text].

Long-Term Outcomes After PCI or CABG for Left Main Coronary Artery Disease According to Lesion Location

OBJECTIVES

The aim of this study was to investigate the impact of lesion site (ostial or shaft vs. distal bifurcation) on long-term outcomes after percutaneous coronary intervention (PCI) or coronary artery bypass grafting (CABG) for left main coronary artery (LMCA) disease.

BACKGROUND

Long-term comparative data after PCI and CABG for LMCA disease according to lesion site are limited.

METHODS

Patients from the MAIN-COMPARE (Revascularization for Unprotected Left Main Coronary Artery Stenosis: Comparison of Percutaneous Coronary Angioplasty Versus Surgical Revascularization) registry were analyzed, comparing adverse outcomes (all-cause mortality [a composite outcome of death, Q-wave myocardial infarction, or stroke] and target vessel revascularization) between PCI and CABG according to LMCA lesion location during a median follow-up period of 12.0 years.

RESULTS

In overall population, the adjusted risks for death and serious composite outcome were higher after PCI than after CABG for distal bifurcation disease, which was mainly separated beyond 5 years. These outcomes were not different for ostial or shaft disease. When comparing drug-eluting stents (DES) and CABG, the adjusted risks for death and serious composite outcome progressively diverged beyond 5 years after DES compared with CABG for distal bifurcation disease (death: hazard ratio: 1.78; 95% confidence interval: 1.22 to 2.59; composite outcome: hazard ratio: 1.94; 95% confidence interval: 1.35 to 2.79). This difference was driven mainly by PCI with a 2-stent technique for distal bifurcation. In contrast, the adjusted risks for these outcomes were similar between DES and CABG for ostial or shaft disease.

CONCLUSIONS

Among patients with distal LMCA bifurcation disease, CABG showed lower mortality and serious composite outcome rates compared with DES beyond 5 years. However, there were no between-group differences in these outcomes among patients with ostial or shaft 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.

Percutaneous coronary intervention in left main disease: SYNTAX, PRECOMBAT, EXCEL and NOBLE-combined cardiology and cardiac surgery perspective

Although coronary-artery bypass grafting (CABG) is the standard choice of revascularization for significant left main coronary artery (LMCA) disease, percutaneous coronary intervention (PCI) for LMCA disease has been widely expanded with adoption of drug-eluting stents (DES). Several small- and moderate-sized trials of CABG and first-generation DES showed that PCI might be a good alternative for selected patients with LMCA disease. However, these early trials were relatively underpowered and comparative results of contemporary DES and CABG were clearly required. Subsequently, two large-sized trials comparing CABG and contemporary DES (EXCEL and NOBLE) were conducted, but these trials showed conflicting results with regards to the effects of PCI and CABG on clinical outcomes, which raises further uncertainty on the optimal revascularization for LMCA disease. This article serves to summarize the key findings of landmark clinical trials, to share our knowledge and experience and to express personal opinions on current controversies in the treatment of LMCA disease.

Percutaneous Coronary Intervention of Left Main Disease

For nearly half a century, coronary artery bypass grafting has been the standard treatment for patients with obstructive left main coronary artery (LMCA) disease. However, there has been considerable evolution in the field of percutaneous coronary intervention, and especially, percutaneous coronary intervention for LMCA disease has been rapidly expanded with adoption of drug-eluting stents. Some, but not all randomized trials, have shown that percutaneous coronary intervention with drug-eluting stents might be a suitable alternative for selected patients with LMCA disease instead of bypass surgery. However, none of previous trials involving early-generation drug-eluting stents was sufficiently powered and comparative trials using contemporary drug-eluting stents were limited. Recently, primary results of 2 new trials of EXCEL (Evaluation of XIENCE Everolimus Eluting Stent Versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization) and NOBLE (Nordic-Baltic-British Left Main Revascularization Study) were reported. However, these trials showed conflicting results, which might pose uncertainty on the optimal revascularization strategy for LMCA disease. In this article, with the incorporation of a key review on evolution of LMCA treatment, we summarize the similarity or disparity of the EXCEL and NOBLE trials, focus on how they relate to previous trials in the field, and finally speculate on how the treatment strategy may be changed or recommended for LMCA treatment.

Left Main Stem Percutaneous Coronary Intervention - Data and Ongoing Trials

Left main stem (LMS) disease is associated with significant morbidity and mortality. Traditionally coronary artery bypass grafting (CABG) has been the gold standard for treatment of these lesions. However over the past decade, percutaneous coronary intervention (PCI) has assumed a more prominent role in the treatment of LMS disease. With the advent of newer drug-eluting stents (DES) with an improved risk factor profile, better intravascular imaging modalities and careful patient selection, the use of PCI in this cohort is expanding. We review the current data to support this and discuss the on-going trials that will hopefully shed more light into the management of this complex disease.

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.

A case of extrinsic compression of the left main coronary artery secondary to pulmonary artery dilatation

Extrinsic compression of the left main coronary artery (LMCA) secondary to pulmonary artery dilatation is a rare syndrome. Most cases of pulmonary artery hypertension but no atherosclerotic risk factors rarely undergo coronary angiography, and hence, diagnoses are seldom made and proper management is often delayed in these patients. We describe a patient that presented with pulmonary hypertension, clinical angina, and extrinsic compression of the LMCA by the pulmonary artery, who was treated successfully by percutaneous coronary intervention. Follow-up coronary angiography showed patent stent in the LMCA in the proximity of the dilated main pulmonary artery. This case reminds us that coronary angiography and percutaneous coronary intervention should be considered in pulmonary hypertension patients presenting with angina or left ventricular dysfunction.

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.

Extrinsic Compression of the Left Main Coronary Artery: A Case of Atrial Septal Defect with Enlarged Pulmonary Artery

We report the case of an adult referred to our center with an initial diagnosis of stenosis of the left main coronary artery (LMCA). A preoperative investigation disclosed an atrial septal defect (ASD) with pulmonary artery hypertension. The angiographic studies confirmed the diagnosis and showed external compression of the LMCA by an enlarged pulmonary artery. Surgical closure of the ASD and tricuspid valve ring annuloplasty with coronary artery bypass surgery (left internal mammary artery to left anterior descending artery) were undertaken. Six months after the surgery, the patient is doing well.

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.

Unprotected left main stenting, short- and long-term outcomes

BACKGROUND

Coronary bypass surgery is recommended for the treatment of left main coronary stenosis. Recently a percutaneous approach has been described as a feasible option.

OBJECTIVES

To present the in-hospital and long-term clinical and angiographic outcome of a consecutive group of patients undergoing stenting for unprotected left main coronary artery (LMCA) disease, and to compare the clinical and angiographic outcomes of drug-eluting stent (DES) versus metal stent (BMS).

METHODS

238 consecutive patients underwent unprotected LMCA stenting. 165 received BMS and 73 received DES. Most patients (88.7%) presented with acute coronary syndrome. Clinical (100%) and angiographic (84%) follow-up was obtained.

RESULTS

Patients' presentation: STEMI (7.2%), non-STEMI (13.5%), unstable angina (67.6%), stable angina (11.7%). Procedural success rate was 100%. In-hospital mortality was 2.1%, all in patients presented with unstable hemodynamic conditions. None of the patients needed emergent CABG. In the long-term follow-up (average three years) there were 12 deaths (5%), 3 patients required CABG and 25 patients required TVR. The overall angiographic LM restenosis rate show a trend toward lower rate in the DES group than the BMS group (9.6% versus 13.8%, P = 0.08). There was no difference in one year mortality (4.1% versus 4.2%) and AMI (2.7% versus 2.8%) between DES and BMS.

CONCLUSIONS

Stenting for LM stenosis can be performed safely with acceptable in hospital and long-term outcome. Reconsideration of current guidelines should be considered. Drug-eluting stent implantation for unprotected LMCA stenosis appears safe with regard to acute and long-term complications and is more effective in preventing restenosis compared to BMS implantation.

Long-term follow-up after nonurgent percutaneous coronary intervention in unprotected left main coronary arteries

OBJECTIVES

To evaluate the long-term outcomes of the selected patients by the local Heart Team to undergo percutaneous coronary intervention (PCI) of unprotected left main coronary artery (ULMCA) stenosis and to compare patients considered at low surgical risk versus at high surgical risk for coronary artery bypass grafting (CABG).

BACKGROUND

CABG is recommended in patients with ULMCA stenosis according to the AHA/ACC and ESC guidelines, and there are limited data on the long-term outcomes in patients selected by the local Heart Team to undergo PCI.

METHODS

Between 1996 and 2007, 227 patients underwent PCI for ULMCA stenosis based on decision of the local Heart Team and patient's and/or physician's preference. All patients were contacted at 1 year and in November 2008.

RESULTS

Long-term follow-up was up to 8 years with a mean of 3.9 +/- 2.6 years. Overall, the Kaplan-Meier estimate of the composite of cardiac death, myocardial infarction (MI), or target lesion revascularization (TLR) was 14.8% at 1 year, 18.3% at 3 years, and 20.9% at 5 years with no events occurring thereafter. Patients considered at low surgical risk for CABG had a significantly lower incidence of cardiac death or MI compared to patients considered at high surgical risk at 8 years (1.4 vs. 16.8%; 1.4 vs. 14.8%, respectively); however, no significant difference was observed for cardiac death, MI, or TLR (18.6 vs. 24.4%).

CONCLUSIONS

PCI of ULMCA stenosis in patients selected by the Heart Team resulted in good long-term clinical outcomes with most events occurring within the 1st year. Patients considered at low surgical risk for CABG have a significantly better long-term survival than patients at high risk for surgery.

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?

On the basis of clinical trials comparing coronary-artery bypass grafting (CABG) with medical therapy, current guideline recommend CABG as the treatment of choice for patients with asymptomatic ischemia, stable angina, or unstable angina/non-ST elevation myocardial infarction who have left main coronary artery disease. Percutaneous coronary intervention can be selectively performed in patients who are candidates for revascularization but who are ineligible for CABG. However, because of advances in periprocedural and postprocedural medical care in patients undergoing either CABG or percutaneous coronary intervention with stenting, new evaluation, and a review of current indications, may be required to determine the standard of care for patients with left main coronary artery disease. Current evidences indicate that stenting results in mortality and morbidity rates that compared favorably with those seen after CABG, suggesting that a current guideline (the Class III recommendation of percutaneous coronary intervention for unprotected left main coronary artery disease) may no longer be justified. Data from several extensive registries and a large clinical trial may have prompted many interventional cardiologists to select percutaneous coronary intervention with stenting as an alternative revascularization strategy for such patients. In addition, these data may inform future guidelines and support the need for well-designed, adequately powered, prospective, randomized trials comparing the 2 revascularization strategies. The cumulative evidence from ongoing and future clinical trials will change the current clinical practice of revascularization for unprotected left main coronary artery disease, which was introduced several decades ago and which has continued to date without major revision.

Coronary artery bypass grafting versus drug-eluting stent implantation for left main coronary artery disease (from a two-center registry)

Recent studies have suggested that percutaneous coronary intervention (PCI) in patients with unprotected left main coronary artery (LMCA) disease renders outcomes comparable to those from coronary artery bypass grafting (CABG). It is necessary to stratify individual patient risk and select the optimal revascularization strategy. We compared the clinical outcomes of patients with unprotected LMCA disease who had undergone PCI with drug-eluting stents or CABG. We identified 462 patients who were treated from January 2003 to December 2006 for unprotected LMCA or LMCA-equivalent disease: 257 had undergone CABG and 205 had undergone PCI with drug-eluting stents. Analyses using propensity scores were performed to minimize the selection bias in the present observational study. After a median follow-up of 33.5 months, no significant difference was found between the CABG and PCI groups in the risk of death (12.1% vs 14.1%, respectively; p = 0.428) or the risk of a composite of death, myocardial infarction, or cerebrovascular accident (17.5% vs 20.0%, respectively; p = 0.434). The rate of major adverse cardiac and cerebrovascular events was significantly lower in the CABG group than in the PCI group (21.8% vs 35.1%, respectively; p = 0.001); the difference was mainly driven by a decrease in the rate of repeat revascularizations (5.1% vs 22.4%; p <0.001). The analyses after propensity score adjustment and matching corroborated the crude group results. In conclusion, PCI with drug-eluting stents showed a safety profile comparable to that of CABG in patients with unprotected LMCA disease. However, the risk of repeat revascularization was significantly greater in the PCI group.

Stenting versus bypass surgery for the treatment of left main coronary artery disease

Based on data comparing coronary-artery bypass grafting (CABG) with medical therapy, the current guidelines recommend CABG as the treatment of choice for patients with left main coronary artery (LMCA) disease. Percutaneous coronary intervention (PCI) can be selectively performed in patients who are candidates for revascularization but who are ineligible for CABG. Current evidence indicates that stenting results in mortality and morbidity rates compared favorably with those seen after CABG. Data from several extensive registries and a large clinical trial may have prompted many interventional cardiologists to choose PCI with stenting as an alternative treatment option for such patients. In addition, these data may inform future guidelines and support the need for well-designed, adequately powered, prospective, randomized trials comparing the two revascularization strategies.

Long-term clinical outcomes of sirolimus- versus paclitaxel-eluting stents for patients with unprotected left main coronary artery disease: analysis of the MAIN-COMPARE (revascularization for unprotected left main coronary artery stenosis: comparison of percutaneous coronary angioplasty versus surgical revascularization) registry

OBJECTIVES

The aim of this study was to evaluate long-term clinical outcomes after implantation of sirolimus-eluting stents (SES) or paclitaxel-eluting stents (PES) among patients with unprotected left main coronary artery (LMCA) disease.

BACKGROUND

There have been few comparisons of long-term outcomes among currently available drug-eluting stents (DES) for the treatment of LMCA disease.

METHODS

A total of 858 consecutive patients with unprotected LMCA stenosis were treated with SES (n = 669) or PES (n = 189) between May 2003 and June 2006. Primary outcome was the composite of death, myocardial infarction (MI), or target vessel revascularization (TVR).

RESULTS

Baseline clinical and angiographic characteristics were similar in the 2 groups. During 3 years of follow-up, the adjusted risk of primary composite outcome was similar among the groups (SES vs. PES: 25.8% vs. 25.7%, hazard ratio [HR]: 0.95, 95% confidence interval [CI]: 0.64 to 1.41, p = 0.79). The 2 groups also showed a comparable adjusted rate of each component of outcome: death (9.1% vs. 11.0%, HR: 0.92, 95% CI: 0.47 to 1.80, p = 0.82), MI (8.1% vs. 8.0%, HR: 0.80, 95% CI: 0.43 to 1.48, p = 0.47), and TVR (12.1% vs. 10.6%, HR: 1.10, 95% CI: 0.53 to 2.29, p = 0.81). The 3-year rates of definite or probable stent thrombosis were 0.6% in the SES group and 1.6% in the PES group (adjusted p = 0.18).

CONCLUSIONS

In consecutive patients with unprotected LMCA disease undergoing DES implantation, SES and PES showed similar long-term clinical outcomes in terms of death, MI, repeat revascularization, and stent thrombosis.

Unprotected left main revascularization in patients with acute coronary syndromes

AIMS

In acute coronary syndromes (ACS), the optimal revascularization strategy for unprotected left main coronary disease (ULMCD) has been little studied. The objectives of the present study were to describe the practice of ULMCD revascularization in ACS patients and its evolution over an 8-year period, analyse the prognosis of this population and determine the effect of revascularization on outcome.

METHODS AND RESULTS

Of 43 018 patients enrolled in the Global Registry of Acute Coronary Events (GRACE) between 2000 and 2007, 1799 had significant ULMCD and underwent percutaneous coronary intervention (PCI) alone (n = 514), coronary artery bypass graft (CABG) alone (n = 612), or no revascularization (n = 673). Mortality was 7.7% in hospital and 14% at 6 months. Over the 8-year study, the GRACE risk score remained constant, but there was a steady shift to more PCI than CABG over time. Patients undergoing PCI presented more frequently with ST-segment elevation myocardial infarction (STEMI), after cardiac arrest, or in cardiogenic shock; 48% of PCI patients underwent revascularization on the day of admission vs. 5.1% in the CABG group. After adjustment, revascularization was associated with an early hazard of hospital death vs. no revascularization, significant for PCI (hazard ratio (HR) 2.60, 95% confidence interval (CI) 1.62-4.18) but not for CABG (1.26, 0.72-2.22). From discharge to 6 months, both PCI (HR 0.45, 95% CI 0.23-0.85) and CABG (0.11, 0.04-0.28) were significantly associated with improved survival in comparison with an initial strategy of no revascularization. Coronary artery bypass graft revascularization was associated with a five-fold increase in stroke compared with the other two groups.

CONCLUSION

Unprotected left main coronary disease in ACS is associated with high mortality, especially in patients with STEMI and/or haemodynamic or arrhythmic instability. Percutaneous coronary intervention is now the most common revascularization strategy and preferred in higher risk patients. Coronary artery bypass graft is often delayed and performed in lower risk patients, leading to good 6-month survival. The two approaches therefore appear complementary.

Stents versus coronary-artery bypass grafting for left main coronary artery disease

BACKGROUND

Several studies have compared the treatment effects of coronary stenting and coronary-artery bypass grafting (CABG). However, there are limited data regarding the long-term outcomes of these two interventions for patients with unprotected left main coronary artery disease.

METHODS

We evaluated 1102 patients with unprotected left main coronary artery disease who underwent stent implantation and 1138 patients who underwent CABG in Korea between January 2000 and June 2006. We compared adverse outcomes (death; a composite outcome of death, Q-wave myocardial infarction, or stroke; and target-vessel revascularization) with the use of propensity-score matching in the overall cohort and in separate subgroups according to type of stent.

RESULTS

In the overall matched cohort, there was no significant difference between the stenting and CABG groups in the risk of death (hazard ratio for the stenting group, 1.18; 95% confidence interval [CI], 0.77 to 1.80) or the risk of the composite outcome (hazard ratio for the stenting group, 1.10; 95% CI, 0.75 to 1.62). The rates of target-vessel revascularization were significantly higher in the group that received stents than in the group that underwent CABG (hazard ratio, 4.76; 95% CI, 2.80 to 8.11). Comparisons of the group that received bare-metal stents with the group that underwent CABG and of the group that received drug-eluting stents with the group that underwent CABG produced similar results, although there was a trend toward higher rates of death and the composite end point in the group that received drug-eluting stents.

CONCLUSIONS

In a cohort of patients with unprotected left main coronary artery disease, we found no significant difference in rates of death or of the composite end point of death, Q-wave myocardial infarction, or stroke between patients receiving stents and those undergoing CABG. However, stenting, even with drug-eluting stents, was associated with higher rates of target-vessel revascularization than was CABG.

Immediate and long-term outcomes of drug-eluting stent implantation for unprotected left main coronary artery disease: comparison with bare-metal stent implantation

BACKGROUND

The efficacy and safety of drug-eluting stent (DES) implantation for unprotected left main coronary artery (LMCA) disease remain to be established in different clinical settings.

METHODS

Elective DES implantation for unprotected LMCA stenosis was performed in 220 patients at the Fu Wai Hospital, China, from April 2003 to February 2006. Data derived from the latter group were compared with those derived from 224 patients treated with bare-metal stents (BMSs) before March 2003 in a Chinese registry of unprotected LMCA stenting.

RESULTS

Compared with the historical BMS control group, the DES group had more multivessel disease and underwent more bifurcation stenting. The inhospital major adverse cardiac events were significantly higher in the DES than in the BMS recipients (4.1% vs 0.9%, P = .030) because of more complex lesions and procedures in the DES group. During the 15-month mean follow-up period, cumulative cardiac death (0.5% vs 4.9%, P = .004), target-vessel revascularization (5.9% vs 11.6%, P = .034), and major adverse cardiac event (9.5% vs 16.5%, P = .029) rates were significantly lower in the DES than in the BMS group. There was no significant difference in clinical efficacy between sirolimus- and paclitaxel-eluting stents. Angiographic follow-up was performed in 46.4% of DES and 45.7% of BMS recipients, respectively; and the binary restenosis rate was significantly lower in the DES versus the BMS control group (16.7% vs 31.4%, P = .014).

CONCLUSIONS

Based on this comparison with a historical control, DES implantation for unprotected LMCA appears safe in selected patients and might be more effective in preventing major adverse cardiac events compared with BMS implantation over a mean follow-up period of 15 months.

Safety and effectiveness of sirolimus-eluting stent implantation for in-stent restenosis of the unprotected left main coronary artery

The present study examined the alternative treatment of sirolimus-eluting stent (SES) implantation for in-stent restenosis (ISR) of the unprotected left main coronary artery (LMCA). Twelve patients underwent SES deployment for bare-metal ISR in the LMCA. ISR were 24+/-11 mm in length and located at the ostial (n=1) and distal (n=11) portion of LMCA. Bifurcation lesions were treated with one of three techniques: the stent crossing the left circumflex artery (n=7), kissing stenting (n=2) or the Crush technique (n=2). All procedures were performed using intravascular ultrasound guidance. Periprocedural CK-MB elevation > or = 3 times normal occurred in 2 patients. There were no cases of significant narrowing in the left circumflex artery after the procedure. At the one-year follow-up, one patient died and there were no incidents of myocardial infarction or target lesion revascularization. The present study suggests that SES implantation may be a feasible therapeutic option for treating ISR in unprotected LMCA.

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.

Percutaneous coronary intervention for left main coronary artery disease

Coronary artery bypass surgery is the currently accepted treatment for unprotected left main coronary artery disease. Currently, the data supporting the safety and efficacy of stents for unprotected left main coronary disease are derived mostly from nonrandomized, single-center studies or registries. These results appear promising but large randomized trials are needed to guide therapy of this potentially lethal disease.

Five-year outcomes after stenting of unprotected left main coronary artery stenosis in patients with normal left ventricular function

BACKGROUND

We analyzed the long-term (5-year) outcome of patients treated with stenting for unprotected left main coronary artery (LMCA) stenosis.

METHODS

Between January 1995 and September 2001, 187 consecutive patients with unprotected LMCA stenosis and normal left ventricular function underwent elective stenting. Patients were examined or interviewed after 1, 3 and 6 months, and every 4 months thereafter for the occurrence of major adverse cardiac events (MACE), including death, myocardial infarction (MI) and target lesion revascularization (TLR).

RESULTS

The procedural success rate was 99.5%. During hospitalization, there were no deaths and only one stent thrombosis. Six-month angiography in 162 patients (follow-up rate, 86.6%) showed a restenosis rate of 33.3%. During 5-year follow-up, there were 13 deaths (6 cardiac, 7 noncardiac) and 2 nonfatal MI. TLRs were required in 36 (20.9%) patients and new lesion revascularizations were required in 13 (5.0%) patients. At 1, 3 and 5 years, the cumulative probabilities for freedom from MACE were 79.9+/-1.8%, 77.5+/-2.5% and 77.5+/-2.5%, respectively.

CONCLUSION

The initial favorable outcomes of patients with normal left ventricular function after stenting of unprotected LMCA stenosis were sustained for up to 5 years.

Stenting of Unprotected Distal Left Main Coronary Artery Bifurcation Stenoses Using Modified Crush Technique with Double Kissing Balloon Inflation (Sleeve Technique): Immediate Procedure Result and Early Clinical Outcome

BACKGROUND

Sleeve technique is a modified version of the crush technique. It is specifically designed to increase the success rate of final kissing balloon inflation, which used to be a major limitation of the latter.

OBJECTIVE

This study sought to look at the feasibility, safety, and early clinical outcome of sleeve technique in stenting of unprotected distal left main coronary artery (LMCA) bifurcation stenoses.

METHODS

From August 2005 to April 2006, 12 consecutive patients with symptomatic distal LMCA bifurcation stenoses of diameter narrowing > or =50%, who refused coronary artery bypass graft surgery, were treated with two-stent strategy using the sleeve technique.

RESULTS

Eleven patients (91.7%) were male, with a mean age of 64.4 +/- 9.3 years. Intravenous abciximab was given to 10 patients (83.3%). The baseline reference vessel diameters of the main vessel and side branch were 3.32 +/- 0.44 and 3.00 +/- 0.58 mm, respectively. After intervention, the minimal luminal diameter was increased from 0.99 +/- 0.46 to 3.26 +/- 0.28 mm and 1.43 +/- 0.71 to 2.93 +/- 0.45 mm in the main vessel and side branch, respectively. The intervention procedure was successful in all patients with 100% final kissing balloon inflation rate. The average procedure time was 58.6 +/- 20.5 minutes. Two patients had a small non-Q myocardial infarction postprocedure. The resultant major adverse cardiac event rate was 16.7% at 30 days after the procedure.

CONCLUSIONS

Sleeve technique is a safe and feasible approach in the stenting of distal LMCA bifurcation stenoses.

Value of magnetic resonance imaging, angiography, and fractional flow reserve to evaluate the left main coronary artery after direct surgical angioplasty

BACKGROUND

Direct surgical angioplasty of the left main coronary artery is aimed to restore a more physiologic blood flow through the left main coronary artery compared with conventional bypass surgery and allows subsequent percutaneous coronary interventions of more distal coronary lesions. Some data on anatomic evaluation with coronary angiography and magnetic resonance imaging (MRI) are known, and we conducted a study to report the physiologic evaluation.

METHODS

Coronary angiography, MRI, and fractional flow reserve measurements were performed in 18 patients 8 years after direct surgical angioplasty of the left main coronary artery.

RESULTS

At coronary angiography and MRI, a dilated funnel-shaped left main coronary artery was seen in all 18 patients, but both methods failed to demonstrate a flow-limiting lesion in the distal left main coronary artery in 1 patient. The functional severity was shown by fractional flow reserve measurement, and subsequently, this patient underwent repeated bypass grafting surgery.

CONCLUSIONS

After long-term follow-up, 17 of 18 patients had an excellent result of direct surgical angioplasty of the left main coronary artery. MRI is a safe and noninvasive way to visualize the left main coronary artery after direct surgical angioplasty, but quantitative assessment of a lesion is not reliable. Fractional flow reserve measurements are mandatory to evaluate the hemodynamic properties of the left main coronary artery after direct surgical angioplasty.

Complex Coronary Interventions: Unprotected Left Main and Bifurcation Lesions

Percutaneous coronary intervention has moved forward with great speed since the advent of stents and now more recently the introduction of drug-eluting technologies. This has seen the modern interventional cardiologist tackle more and more complex coronary lesions, of which unprotected left main (ULM) and bifurcations still remain challenging and controversial. ULM coronary artery stenosis traditionally remains a surgical indication although there have been recent reports and studies demonstrating the feasibility of a percutaneous strategy in select patient groups. Furthermore, drug-eluting stents have shown great benefit in reducing the problem of restenosis and have also become the mainstay treatment modality for bifurcation lesions with a choice between one- or two-stent strategies determined by the extent of disease burden in the main vessel and side branch and the response of the side branch ostium following treatment of the main vessel. This article will provide a contemporary review of percutaneous intervention for these two lesion subsets and describe the relative merits of each of the different strategies in current use with a glimpse into what the future may hold.