Treatment Of Left Main Coronary Artery Research Articles

RACER renal stents for large diameter left main coronary artery intervention

Stenosis of the left main coronary artery (LMCA) portends a high risk of cardiovascular mortality and morbidity. Traditionally, CABG has been considered the gold standard for treatment of LMCA disease; however, increasingly percutaneous coronary intervention (PCI) has become the revascularization strategy of choice as studies have demonstrated acceptable short and long-term clinical outcomes. As a result of intervening more proximally in the coronary tree, interventional cardiologists are increasingly placing stents in very large coronary arteries (>5mm) which poses specific challenges given the current sizing of commercial coronary stents.

Percutaneous Unprotected Left Main Coronary Artery Interventions – Updated Results and Current Recommendations

Current guidelines recommend coronary artery bypass grafting (CABG) as the treatment of choice for patients who have unprotected left main coronary artery disease (ULMCA). Several registries and two randomised controlled clinical trials have shown that hard end-points such as cardiac death, myocardial infarctions and cerebrovascular events are similar following percutaneous coronary intervention (PCI) with drug-eluting stent (DES) implantation compared with CABG. However, current American and European guidelines do not endorse PCI as an appropriate alternative to CABG for patients with ULMCA. In this article we review the current evidence on PCI with DES for ULMCA stenosis treatment and propose future directions in this evolving topic of great interest.

AS-116: Incidence and Clinical Significance of Neomembrane at the New Carina After Kissing Stenting in Unprotected Left Main Coronary Artery Intervention

AS-116: Incidence and Clinical Significance of Neomembrane at the New Carina After Kissing Stenting in Unprotected Left Main Coronary Artery Intervention

Safety and Efficacy of Coronary Drug-Eluting Stents in Octogenarians

The effectiveness of coronary drug-eluting stents has not been fully studied in very elderly patients who have clinical features that predispose them to side effects and long-term adverse events. The safety and efficacy of drug-eluting stents were studied in a historical cohort of consecutive octogenarian patients who underwent percutaneous coronary intervention. Between 2002 and 2006, 176 octogenarian patients were treated using coronary stents: 90 with drug-eluting stents and 86 with bare-metal stents only. Patients treated using drug-eluting stents had a greater number of diseased vessels (2.28+/-0.85 vs. 1.87+/-0.87; P=.002), had more vessels treated (1.74+/-0.79 vs. 1.17+/-0.47; P< .0005), were more likely to have multivessel disease (79% vs. 59%; P=.005) and to undergo left main coronary artery treatment (20% vs. 1.0%; P< .0005), and had longer (26.6+/-6.7 mm vs. 16.6+/-4.9 mm; P< .0005) and smaller diameter (2.91+/-0.4 mm vs. 3.04+/-0.4 mm; P=.049) lesions. The median follow-up period was 26.3+/-12.9 months (in 98.3% of patients). After adjustment for other variables and for the likelihood of receiving a drug-eluting stent (i.e., the propensity score), there was no significant relationship between the type of coronary stent used and either mortality or the occurrence of adverse clinical events at 1 year of follow-up. With careful clinical selection of patients, the use of drug-eluting stents in octogenarians with highly unfavorable angiographic characteristics can be as safe and effective as conventional stents for treating low-risk coronary lesions.

Excimer laser debulking for percutaneous coronary intervention in left main coronary artery disease

Excimer laser has been successfully applied to complex atherosclerotic plaques in acute coronary syndromes; however, its role in debulking in left main coronary artery disease has not been fully explored. Details of a series of 20 patients who underwent excimer laser revascularization of a spectrum of left main coronary artery lesions are presented. Twenty symptomatic patients who received excimer laser debulking were examined for procedural outcome and follow up results. The left main coronary artery was characterized as protected, semi-protected, poorly protected, or unprotected, depending on the presence or absence of patent bypass grafts to the left anterior descending (LAD) and circumflex (CX) arteries. A fully protected left main coronary artery (LMCA) was present in only 20% of the patients. The target lesions included 11(55%) distal LMCA stenoses, six (30%) ostial stenoses, and one (5%) mid-portion lesions. Two (10%) patients had in-stent re-stenosis of the entire length of the LMCA. Small (0.7 mm-1.4 mm) excimer laser catheters were mostly used. A relatively high number of laser energy pulses (1,334 +/- 643) were required to achieve adequate debulking. Successful LMCA intervention was performed in 19 (95%) patients, while in-hospital complications occurred in only one (5%) patient. Subacute/late stent thrombosis developed 3 months after the procedure in one patient, and two patients died from non-cardiac causes during follow-up. Lesions in LMCAs can be revascularized in selected patients by laser debulking and adjunct stenting. Inadequate protection by bypass grafts and decreased left ventricular function do not contradict utilization of excimer laser. Small laser catheters and high energy levels are required during laser debulking of stenoses of left main coronary arteries.

Change We Can Believe In: The Hyper-Evolution of Percutaneous Coronary Intervention for Unprotected Left Main Disease With Drug-Eluting Stents

The initial adoption of percutaneous coronary intervention (PCI) for unprotected left main coronary artery (LMCA) obstruction was tempered by poor acute outcomes after balloon angioplasty and the potential lethality of restenosis in the left main trunk suggested by bare-metal stent registries.1 The marked antirestenotic efficacy of drug-eluting stents (DES) ushered in a new wave of enthusiasm for unprotected LMCA intervention. However, the accumulation of robust data to guide and support clinical practice has been challenged by the relatively low prevalence of this lesion subset combined with its historical characterization as a “forbidden zone” for PCI. The DES left main database has grown from initial, small, single-center experiences2–4 to larger multicenter registries,5 prospective, risk-adjusted comparisons with coronary artery bypass grafting,6 and most recently to small randomized clinical trials and prespecified subgroups of larger clinical trials.7,8 Catalyzed by an ethos in interventional cardiology that embraces (1) investigation, (2) dissemination of new information through journals, conferences, and a tradition of live-case demonstration; and (3) rapid adaptation of new techniques, there has been a marked evolution and improvement of the technical approach to unprotected LMCA intervention in a remarkably short period of time. The study reported by Palmerini et al9 in this issue of the Circulation Cardiovascular Intervention provides further pressure on interventional cardiologists to follow a straightforward maxim: simpler is usually better. Article see p 185 The interpretation of the studies of left main PCI with DES has been complicated by heterogeneity within study populations related to both the disease location (ostial, shaft, or distal bifurcation) and the technical approach used (single stent, dedicated 2-stent technique, or provisional stenting of the left main with “bail-out” stenting of the branch vessel). The early, single-center observational studies of DES for the unprotected LMCA demonstrated the dependence of clinical outcome …

Distal Left Main Coronary Disease Is a Major Predictor of Outcome in Patients Undergoing Percutaneous Intervention in the Drug-Eluting Stent Era: An Integrated Clinical and Angiographic Analysis Based on the Rapamycin-Eluting Stent Evaluated At Rotterdam Cardiology Hospital (RESEARCH) and Taxus-Stent Evaluated At Rotterdam Cardiology Hospital (T-SEARCH) Registries

This study sought to investigate whether the anatomical location of the disease carries prognostic implications in patients undergoing drug-eluting stent (DES) implantation for the left main coronary artery (LMCA) stenosis. Liberal use of DES, compared with a bare metal stent (BMS), has resulted in an improved outcome in patients undergoing LMCA intervention. However, the overall event rate in this subset of patients remains high, and alternative tools to risk-stratify this population beyond conventional surgical risk status would be desirable. From April 2002 to June 2004, 130 patients received DES as part of the percutaneous intervention for LMCA stenoses in our institution. Distal LMCA disease (DLMD) was present in 94 patients. They were at higher surgical risk and presented with a greater coronary disease extent compared with patients without DLMD. After a median of 587 days (range 368 to 1,179 days), the cumulative incidence of major adverse cardiac events (MACE) was significantly higher in patients with DLMD at 30% versus 11% in those without DLMD (hazard ratio [HR] 3.42, 95% confidence interval [CI] 1.34 to 9.7; p = 0.007), mainly driven by the different rate of target vessel revascularization (13% and 3%; HR 6, 95% CI 1.2 to 29; p = 0.02). After adjustment for confounders, DLMD (HR 2.79,95% CI 1.17 to 8.9; p = 0.032) and surgical risk status (HR 2.18,95% CI 1.06 to 4.5; p = 0.038) remained independent and complementary predictors of MACE. Distal LMCA disease carries independent prognostic implications, and it may help in selecting the most appropriate patient subset for LMCA intervention beyond the conventional surgical risk status in the DES era.

Serial Angiographic Follow-Up of Sirolimus-Eluting Stents for Unprotected Left Main Coronary Artery Revascularization

This study was performed to evaluate the clinical and serial angiographic outcomes of patients undergoing sirolimus-eluting stent (SES) implantation for unprotected left main coronary artery (LMCA) stenosis. The efficacy of SES has led to their expanded use for off-label indications, including LMCA disease. Unprotected LMCA intervention with SES was attempted in 50 patients. Surveillance angiography was performed at three and nine months' follow-up. The target lesion involved the distal LMCA in 47 patients (94%). In-lesion restenosis occurred in 21 patients (42%), was focal in 85% of cases, and in 82% involved the branch ostia, sparing the LMCA itself. Target lesion revascularization (TLR) occurred in 19 patients (38%) over a mean follow-up of 276 +/- 57 days; TLR was ischemia-driven in 7 patients (14%). Late loss was significantly greater within the left circumflex (LCX) ostium compared to the parent vessel (PV) of the LMCA bifurcation (0.83 +/- 0.89 mm vs. 0.49 +/- 0.72 mm, p = 0.04). Late loss continued to increase between three- and nine-month follow-up. Final minimal luminal diameter and maximal balloon pressure were independent predictors of restenosis of the PV. Restenosis is a frequent finding when serial angiographic follow-up is performed after SES implantation for unprotected distal LMCA lesions. Restenosis is usually focal, most often involves the LCX ostium, and often occurs without symptoms.

The French Registry of left main coronary artery treatment: Preliminary results

The French Registry of left main coronary artery treatment: Preliminary results

3655 Final results of the French registry of left main coronary artery treatment

3655 Final results of the French registry of left main coronary artery treatment

One-year follow-up after intravascular ultrasound assessment of moderate left main coronary artery disease in patients with ambiguous angiograms

OBJECTIVESThe purpose of this study was to correlate angiographic and intravascular ultrasound (IVUS) findings in left main coronary artery (LMCA) disease and identify the predictors of coronary events at one year in patients with LMCA stenoses.BACKGROUNDSignificant (≥50% diameter stenosis [DS]) LMCA disease has a poor long-term prognosis.METHODSOne hundred twenty-two patients who underwent angiographic and IVUS assessment of the severity of LMCA disease and who did not have subsequent catheter or surgical intervention were followed for one year. Standard clinical, angiographic and IVUS parameters were collected.RESULTSThe quantitative coronary angiography (QCA) reference diameter (3.91 ± 0.76 mm, mean ± 1 SD) correlated moderately with IVUS (4.25 ± 0.78 mm, r = 0.492, p = 0.0001). The lesion site minimum lumen diameter (MLD) (2.26 ± 0.82 mm) by QCA correlated less well with IVUS (2.8 ± 0.82 mm, r = 0.364, p = 0.0005). The QCA DS measured 42 ± 16%. During the follow-up period, 4 patients died, none had a myocardial infarction, 3 underwent catheter-based LMCA intervention and 11 underwent bypass surgery. Univariate predictors of events (p < 0.05) were diabetes, presence of another lesion whether treated with catheter-based intervention or untreated with DS > 50% and IVUS reference plaque burden and lesion lumen area, maximum lumen diameter, MLD, plaque area and area stenosis. Using logistic regression analysis diabetes mellitus, an untreated vessel (with a DS > 50%) and IVUS MLD were independent predictors of cardiac events.CONCLUSIONSIn selected patients assessed by IVUS, moderate LMCA disease had a one-year event rate of only 14%. Intravascular ultrasound MLD was the most important quantitative predictor of cardiac events. For any given MLD, the event rate was exaggerated in the presence of diabetes or another untreated lesion (>50% DS).

Impact of stents on clinical outcomes in percutaneous left main coronary artery revascularization

Despite effective treatment of left main coronary artery (LMCA) disease by coronary bypass, there is still need for treatment of the LMCA due to progression of disease or bypass graft failure. We compared the in-hospital and follow-up (1-year) outcomes of patients with LMCA stenosis treated with stents (n = 88), with a matched group of patients undergoing LMCA non-stent procedures (n = 36). Ninety-seven percent of patients in each group underwent previous coronary bypass. Procedural success (angiographic success without major in-hospital complications) tended to be higher in stent patients than in their non-stent counterparts (98% vs 92%, p = 0.12), and overall procedural complications were higher for the non-stent group (5.4% vs 0%, p = 0.03). The incidence of non–Q-wave myocardial infarction was higher in patients with the LMCA treated with stents than in non-stent patients (13% vs 2.7%, p = 0.09). There was no difference in death or Q-wave myocardial infarction between the 2 groups during follow-up. Overall target lesion revascularization at 1 year was 15% after LMCA stenting, and 18% in non-stent patients (p = 0.71). Also, any cardiac event-free survival (including death, Q-wave myocardial infarction, coronary bypass, or angioplasty) was similar for both groups (78% for stents vs 76% for non-stents, p = 0.85). We conclude that in patients undergoing LMCA interventions, stents reduce major hospital complications, but may not significantly reduce repeat revascularization or major cardiac events at 1 year compared with non-stent LMCA procedures.

Value of transesophageal echocardiography during complex or high-risk coronary interventions in the cardiac catheterization laboratory

The increasing complexity of coronary intervention and the limitations of hemodynamic and electrocardiographic monitoring have facilitated the introduction of new imaging techniques in the cardiac catheterization laboratory. Transesophageal echocardiography (TEE) has proved valuable for left ventricular (LV) monitoring during high-risk surgery, but its reported use in the cardiac catheterization laboratory has been limited. Accordingly, we assessed the feasibility and value of TEE during complex or high-risk coronary intervention in the catheterization laboratory. The TEE probe was successfully introduced in 53 of 54 (98%) attempted cases. The primary imaging goals were LV monitoring in 39 (74%), left main coronary artery (LMCA) imaging in 9 (17%) and both in 5 (9%) cases. LV monitoring was successful in 43 of the 44 (98%) attempted cases. In 25 (58%) of these, additional important observations were made by TEE that were not apparent by symptoms, or hemodynamic, electrocardiographic or radiographic monitoring. These included unexpected changes in regional myocardial function (n = 20), alteration in LV size (n = 2), exclusion of considered pericardial tamponade (n = 2) and detection of unsuspected mitral regurgitation (n = 1). Management of the interventional procedure was directly influenced by the findings of TEE in 11 of the 43 (26%) monitored cases. The LMCA was successfully visualized in 13 of the 14 (93%) attempted cases. In 11 of these, measurement of the stenotic lesion diameter by TEE correlated well with quantitative angiography both before (r = 0.83, standard error of the estimate = 0.01, p < 0.002) and after (r = 0.80, standard error of the estimate = 0.03, p < 0.005) intervention. All patients tolerated TEE well without complications. TEE during complex or high-risk coronary intervention is a feasible, safe and valuable tool for rapid detection of altered myocardial function and thus may influence clinical decisions during interventional procedure. In patients undergoing LMCA intervention, TEE accurately measures stenotic lesion diameter before and after intervention, providing a feasible noninvasive means for follow-up.