Significant Left Main Stenosis Research Articles

PET-determined myocardial perfusion and flow in coronary artery disease characterization

Positron emission tomography (PET) myocardial perfusion imaging in conjunction with tracer-kinetic modeling enables the concurrent assessment of myocardial perfusion and regional myocardial blood flow (MBF) of the left ventricle in absolute terms in milliliters per gram per minute (mL/g/min). The non-invasive quantification of MBF during pharmacologically induced hyperemia, at rest, and corresponding myocardial flow reserve (MFR) opens a new avenue for the identification and characterization of classical or endogen type of coronary microvascular dysfunction (CMD) as functional substrate for microvascular angina in patients with non-obstructive coronary artery disease (CAD) and/or no CAD at all. Further, PET-MBF quantification expands the scope of conventional myocardial perfusion imaging from the identification of advanced, and flow-limiting, epicardial CAD to early stages of atherosclerosis and/or CMD. Adding MBF assessment to myocardial perfusion may also reliably unravel diffuse ischemia owing to significant left main stenosis and/or multivessel CAD, commonly confirmed by peak stress transient ischemic cavity dilation of the left ventricle during maximal vasomotor stress compared to rest on gated PET images. Owing to high spatial and contrast resolution in conjunction with photon-attenuation free myocardial perfusion PET images, PET is preferentially used for CAD detection in advanced obesity and women with pronounced breast habitus. With increasing clinical use of cardiac PET perfusion and MBF assessment, individualized, and image-guided cardiovascular treatment decisions in CAD patients is likely to ensue, while its translation into improved cardiovascular outcome remains to be investigated.

Evidence-based Management of Left Main Coronary Artery Disease

Left main coronary artery disease (LMCAD) is associated with high morbidity and mortality due to the large myocardial mass at risk. Although medical treatment may be an option in selected low-risk patients, revascularisation is recommended to improve survival in the majority of patients presenting with a significant left main stenosis. In the past decade, multiple randomised clinical trials and meta-analyses have compared coronary artery bypass grafting surgery (CABG) versus percutaneous coronary intervention (PCI), finding controversial results. The strategy for LMCAD revascularisation is still challenging. Coronary anatomy complexity, clinical features and patient preferences are key elements to be considered by the heart team. The current guidelines define CABG as standard therapy, but the continuous improvements in PCI techniques, the use of intracoronary imaging and functional assessment make PCI a feasible alternative in selected patients, particularly in those with comorbidities and contraindications to CABG. This review analyses the most important studies comparing CABG versus PCI in patients with LMCAD.

Predicting left main stenosis in stable ischemic heart disease using logistic regression and boosted trees

BackgroundThe ISCHEMIA trial showed similar cardiovascular outcomes of an initial conservative strategy as compared with invasive management in patients with stable ischemic heart disease without left main stenosis. We aim to assess the feasibility of predicting significant left main stenosis using extensive clinical, laboratory and non-invasive tests data. MethodsAll adult patients who had stress testing prior to undergoing an elective coronary angiography for stable ischemic heart disease in Ontario, Canada, between April 2010 and March 2019, were included. Candidate predictors included comprehensive demographics, comorbidities, laboratory tests, and cardiac stress test data. The outcome was stenosis of 50% or greater in the left main coronary artery. A traditional model (logistic regression) and a machine learning algorithm (boosted trees) were used to build prediction models. ResultsAmong 150,423 patients included (mean age: 64.2 ± 10.6 years; 64.1% males), there were 9,225 (6.1%) with left main stenosis. The final logistic regression model included 24 predictors and 3 interactions, had an optimism-adjusted c-statistic of 0.72 and adequate calibration (optimism-adjusted Integrated Calibration Index 0.0044). These results were consistent in subgroups of males and females, diabetes and non-diabetes, and extent of ischemia. The boosted tree algorithm had similar accuracy, also resulting in a c-statistic of 0.72 and adequate calibration (Integrated Calibration Index 0.0054). ConclusionsIn this large population-based study of patients with stable ischemic heart disease using extensive clinical data, only modest prediction of left main coronary artery disease was possible with traditional and machine learning modelling techniques.

ANGIOGRAPHIC PREDICTORS OF CTO PCI SUCCESS: HOW TO GUIDE DECISION MAKING BEYOND THE J-CTO SCORE

ANGIOGRAPHIC PREDICTORS OF CTO PCI SUCCESS: HOW TO GUIDE DECISION MAKING BEYOND THE J-CTO SCORE

Patient Characteristics, Procedural Details, and Outcomes of Contemporary Percutaneous Coronary Intervention in Real-World Practice: Insights from Nationwide Thai PCI Registry.

Background Percutaneous coronary intervention (PCI) practice and outcomes vary substantially in different parts of the world. The contemporary data of PCI in Asia are limited and only available from developed Asian countries. Objectives To explore the pattern of practice and results of PCI procedures in Thailand as well as a temporal change of PCI practice over time compared with the registry from other countries. Methods Thai PCI Registry is a prospective nationwide registry that was an initiative of the Cardiac Intervention Association of Thailand (CIAT). All cardiac catheterization laboratories in Thailand were invited to participate during 2018-2019, and consecutive PCI patients were enrolled and followed up for 1 year. Patient baseline characteristics, procedural details, equipment and medication use, outcomes, and complications were recorded. Results Among the 39 hospitals participated, there were 22,741 patients included in this registry. Their mean age (standard deviation) was 64.2 (11.7) years and about 70% were males. The most common presentation was acute coronary syndrome (57%) with a high proportion of ST-elevation myocardial infarction (28%). Nearly two-thirds of patients had multivessel disease and significant left main stenosis was reported in 11%. The transradial approach was used in 44.2%. The procedural success rate was very high (95.2%) despite the high complexity of the lesions (56.9% type C lesion). The incidence of procedural complications was 5.3% and in-hospital mortality was 2.8%. Conclusion Thai PCI Registry provides further insights into the current practice and outcomes of PCI in Southeast Asia. The success rate was very high, and the complications were very low despite the high complexity of the treated lesions.

Science, Medicine, and the Anesthesiologist

Science, Medicine, and the Anesthesiologist

The Value of Stress Echocardiography Imaging and Functional Parameters in Patients with aVR Lead ST-Segment Elevation during an Exercise Stress Test to Detect Significant Left Main Stenosis.

To evaluate the role of functional and imaging parameters during exercise stress echocardiography (SE) in the presence of ST-segment elevation (ST-E) in aVR leads to predict significant left main/left main equivalent/or ostial left anterior descending (LAD) stenosis (LM+). The study population included 548 patients with ECG and echo markers of myocardial ischemia, in whom diagnostic coronary angiography was performed. We analyzed the patients' clinical characteristics, ECG changes, wall motion score index (WMSI) by stress echocardiography (SE), as well as functional capacity during exercise (METs) and Duke treadmill score. aVR ST-segment elevation was found in 60/548 (11%) patients, whereas aVR ST-E was found in 23/57 patients with left main LM stenosis (Sn 40%, Sp 92%, PPV 38%, NPV 93%). When aVR ST-E was combined with other functional/imaging parameters, patients with aVR ST-E and LM+ had significantly worse functional capacity in METs (5.0±2.2 vs. 6.7±2.3, P=0.005), lower Duke score (-6.8±6.8 vs. -3.6±4.1, P=0.049), and higher deterioration of WMSI (0.51±0.24 vs. 0.39±0.24, P=0.046). Significant multivariable predictors of the left main (LM) stenosis were aVR ST-E and positive SE in LAD territory in the whole group of patients, and Delta WMSI, Duke score and METs achieved in patients presented with aVR ST-E during exercise. The aVR ST-segment alone has intermediate sensitivity in detecting significant LM stenosis in patients referred to SE testing for chest pain. When combined with other functional and imaging parameters, including poor exercise functional capacity in METs, lower Duke score or greater WMA in the territory of LAD, its diagnostic power to detect LM significantly increases.

Catheter Induced Left Main Coronary Artery Dissection: Incidence, Management and Medium-term Outcome ?? A Study of Contemporary Practice

Background: Catheter-induced left main (LM) coronary artery dissection is rare but requires immediate intervention. In this situation, the results of emergency percutaneous intervention (PCI) using DES to restore the flow in the left coronary artery are poorly known. Aims of the Study: To examine the incidence, clinical and angiographic features as well as the longer-term outcomes of iatrogenic LM dissection. The strategy for coronary revascularization was emergency PCI using DES. Methods: A study of all 24,995 coronary procedures performed in our institution (comprising 2 catheter-laboratories) during eight years in succession (1 April 2009- 1 April 2017). Cases of iatrogenic LM dissection were identified and studied in detail and clinical follow-up was obtained in all patients in whom iatrogenic LM dissection occurred. Results: Catheter-induced dissection of the LM occurred in 20 patients, representing 0.08 % of the all procedures: 16/8,019 PCI (0.2%) and 4/16,976 diagnostic angiograms (0.02%). Significant LM stenosis was present in 7/20 patients. No specific causal catheter was identified. LM coronary artery dissection was obstructive in 5 patients and involved the distal LM in 70%. Hemodynamic status was immediately impaired in 11/20 patients. The strategy for LM PCI was provisional stenting of the side branch after LM and main vessel stenting with final kissing inflation. Angiographic success was obtained in 18/20 and in these patients in-hospital outcome was free of events or re-intervention. PCI failed to restore blood flow in 2 patients who died during PCI attempt. During follow-up repeat revascularization was required in 2 patients (1 CABG 1 re-PCI) but there were no other adverse events. Conclusion: Catheter-induced LM coronary artery dissection is a rare complication with an incidence of less than 1 in 1000 coronary procedures overall, but with a mortality rate in this study of 10%. Emergency PCI with DES is an effective and appropriate treatment associated with a favourable midterm outcome.

Angiographic SYNTAX score reduction in de novo left main coronary stenosis patients over the last decade: implications for revascularization approach

Abstract Introduction Percutaneous management of left main (LM) coronary artery stenosis is an acceptable alternative to surgery in selected group of patients. Purpose To investigate potential angiographic trends in de novo LM coronary artery stenosis patients. Those may impact revascularization mode but remain undetermined. Methods Clinical records and all consecutive coronary angiograms in our Institution from 1st January 2010 to 31stDecember 2019 were evaluated to identify those with newly diagnosed angiography-significant (≥50% lumen diameter reduction) LM stenosis. Angiographic SYNTAX score (SS) assessment was performed by agreement of two experienced analysts (an angiographic core lab analyst and a Heart Team interventional cardiologist) on anonymized angiograms. Values of the overall SS, SS of the LM lesion and SS beyond LM were determined according to SS assessment methodology. Pearson's correlation and Fisher transformation were used to evaluate parametric variables. Spearman's rho was used to determine trends. Results Overall, out of 12315 coronary angiographies performed in de novo referrals in the last decade, 357 (2.90%) showed significant left main stenosis; the proportion varied from 2.30% to 3.48% annually. Patient mean age was 68.8 years (23.3% women). No temporal trends in patient age or gender occurred over the last decade while the overall SS deceased from a mean value of 35 to 28 (SC=−0.16, p=0.003). Further analysis showed a particular negative trend in the non-LM-SS (SC=−0.17, p=0.001) but not in the LM-SS (SC=0.04, p=0.47). No temporal trend was present is the prevalence of isolated LM stenosis (p=0.48) and no temporal trend in the LM stenosis angiographic severity (<70% vs. ≥70%; p=0.61), LM stenosis location (ostial/mid/bifurcation/entire left main; p=0.30) nor in the number of LM segments affected (SC=0.05, p=0.30). Reduction in the non-LM-SS was associated with a decrease in the number of coronary arteries with a significant angiographic atherosclerotic involvement (SC=−0.12, p=0.03) and in the number of coexisting total occlusions (SC=−0.25, p<0.001). Conclusion(s) (1) In patients with newly diagnosed LM critical stenosis overall angiographic SS showed a statistically significant negative trend over last decade, with a reduction from mean 35 (2010) to 28 points (2019); a finding that may be related to a change in the angiographic presentation of the disease or an earlier identification of LM stenosis patients over time. (2) The overall SS reduction was driven by a decrease in non-LM-SS. This, taken together with the overall SS reduction from above 32 to below 32, favours (as per current guidelines) the endovascular approach to left main revascularization. Our findings suggest an increase in the proportion of LM stenosis patients with angiography feasible to percutaneous intervention. SYNTAX score trends over the last decade Funding Acknowledgement Type of funding source: None

Clinical presentation of patients with significant left main stenosis.

Objectives: Our objective was to evaluate the frequency of clinical presentation in patients with angiographically documented significant LMCA stenosis. Study Design: Cross sectional study. Setting: Department of Cardiac Catheterization and Interventional Cardiology, Punjab Institute of Cardiology Lahore. Period: Six Months from July to December 2018. Results: The mean age of presentation of disease was 59.78±5.76 year, 100 being males (58.82%) and 70 females (41.18%). Regarding frequency of distribution of symptoms, the most common symptom was chest pain. ST segment depression was most common finding (52.94%) on ECG. 50% of patients presented with stable angina,29.41% with unstable angina,8.82% with NSTEMI and 11.76% with STEMI.40% had pulmonary edema at initial presentation. Conclusion: LMCA stenosis is more common in males associated with severe disease in other coronary arteries. Isolated left main disease is rare and is more common in females as compared to males. Atherosclerosis was the major cause LMCA stenosis in the studied population. Severe forms of angina along with diffuse ST depression in multiple ECG leads are common findings in patients with LMCA stenosis.

Surgical treatment for left main coronary artery stenosis in patients of advanced age

Objective To analyze the clinical efficacy of coronary artery bypass grafting(CABG)in patients of advanced age with left main coronary artery disease(LMCAD). Methods From 2005 to 2014, 101 elderly patients(≥80 years)with LMCAD underwent off-pump CABG in our hospital.Among them, 82 were male and 19 were female, with an average age of(81.4±1.7)years.Seventy-six cases(75.2%)had significant left main stenosis(≥70%)and twenty-five cases had left main stenosis less than 70%.The average left ventricular end diastolic diameter was(48.2±8.3)cm; left ventricular ejection fraction was more than 50% in 89 cases and 30% to 50% in 12 cases.Fourteen cases had mitral insufficiency and one had ventricular aneurysm.In addition, 56 patients had New York Heart Association functional classification Ⅰ to Ⅱ, and 45 patients had classification Ⅲ to Ⅳ.Ninety-nine patients had Canadian Vascular Society(CCS)classification of angina pectoris Ⅰto Ⅲ, two had classification Ⅳ and thirteen had acute myocardial infarction.Six patients were implanted with intra-aortic balloon counterpulsation before CABG. Results The average operation time was(3.9±0.8)h, the average number of bridging vessels were(3.0±1.0)roots, ICU monitoring time was(50.2±46.0)h, and ventilator assisted breathing time was(42.9±68.5)h.Six patients(5.9%)had secondary thoracotomy hemostasis, five(4.9%)had secondary tracheal intubation, and four(4.0%)had continuous dialysis.Intra-aortic balloon counterpulsation was implanted in 3cases(2.9%)during operation and in 11 cases(10.9%)after operation.Two cases(2.0%)had perioperative myocardial infarction and 8 cases(7.9%)died after operation during hospitalization.The median follow-up time was 6(1-11)years, and 17(16.8%)had all-cause mortality. Conclusions Although the two independent high-risk factors, old age and left main stenosis often coexist, off-pump CABG and perioperative management are still safe and effective treatments. Key words: Coronary disease; Coronary artery bypass, off-pump

Prediction of complications and death in octogenarians with left main coronary artery disease after coronary artery bypass implantation - off-pump, on-pump and minimally invasive techniques comparison.

IntroductionOff-pump coronary artery bypass grafting is considered potentially more effective than on-pump surgery in elderly patients.AimTo compare the early and long-term results of these techniques in patients ≥ 80 years of age with left main coronary artery disease.Material and methodsAll patients ≥ 80 years of age (N = 3648) who were reported to the Polish National Registry of Cardiac Surgery Procedures between 2006 and 2016 and underwent primary, isolated coronary artery bypass surgery were included in the study. The patients were divided into 2 groups: group A – without significant left main stenosis (LMS) (n = 2094) and B group – with LMS ≥ 50% (n = 1524). The groups were compared according to the type of surgery: on-pump (A = 1107 vs. B = 891), off-pump (A = 908 vs. B = 616) and MIDCAB (A = 79 vs. B = 17).ResultsThere were significant differences in preoperative status between the groups in the whole cohort, which were not observable after propensity score matching. The in-hospital mortality was significantly higher in the LMS group operated on-pump (10.5% vs. 7.0%; p = 0.01) and non-significant in the off-pump group (5.1% vs. 5.7%; p = 0.78), as well as in the MIDCAB subgroup (5.9% vs. 5.1%; p = 0.64). 10-year survival in all subgroups was comparable and remained at a level of 50–60%. The mean entire cohort follow-up was 3.4 ±2.7 vs. 3.7 ±2.8 years (p = 0.2).ConclusionsOff-pump coronary bypass grafting may optimize the outcomes in elderly patients with significant left main stenosis. Octogenarians surgically treated for coronary artery disease, despite increased post-operative risks, present encouraging long-term survival.

A case-vignette based assessment of patient's perspective on coronary revascularization strategies, the OPINION study

Background and aimsSignificant left main (LM) stem disease is potentially life-threatening and mandates revascularization. This study aimed to assess how patients rate the importance of particular features of coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI), how this determines their preference for a particular treatment strategy, and whether particular personality characteristics influence this preference. Methods and resultsIn total, 1145 patients who visited the outpatient clinic of the Erasmus Medical Center for stable coronary artery disease were asked to complete a case vignette-questionnaire on a hypothetical significant LM stenosis amenable to PCI or CABG. To assess the individual's personality disposition and general distress level, each patient had to complete a set of 3 standardized, validated questionnaires with satisfactory psychometric properties. Overall 89% of patients preferred PCI to CABG. PCI was the preferred strategy despite a higher risk for repeat revascularization and need for more medication. Remarkably, the fact that a risk for repeat revascularization is more common in the PCI group is less important for the patients who opt for PCI. Risk for stroke and bleeding were the most important arguments to opt for PCI over CABG. Type D personality, depression, and anxiety were all associated with a relatively higher preference for CABG as revascularization strategy. ConclusionOverall, when given the choice patients seem to have a clear preference for PCI over CABG and consider stroke and bleeding important procedure-related complications. Patients with Type D personality, depression, or anxiety favor CABG.

111 Improved Clinical Outcomes with Multi-Vessel Compared to Culprit only Percutaneous Coronary Intervention in Patients Presenting with Acute ST Elevation Myocardial Infarction

Introduction In patients with acute ST elevation myocardial infarction (STEMI), percutaneous coronary intervention (PCI) improves survival. Multi-vessel coronary disease is identified in up to two thirds of patients and is associated with poorer outcomes. Historically, registry data and guidelines favoured culprit only PCI in STEMI, although recent data suggest that more complete revascularisation may improve outcomes. To examine this issue locally, we studied clinical outcomes in consecutive patients presenting with STEMI and multivessel disease in SE Scotland stratified according to revascularisation strategy (culprit versus multivessel angioplasty). Methods We retrospectively examined clinical outcomes according to revascularisation strategy (culprit versus multi-vessel) in all patients with multivessel disease (defined as >70% lumen stenosis in at least one non-infarct artery that was suitable for revascularisation) undergoing PCI for STEMI in SE Scotland, October 2013 – August 2014. Patients with significant left main stenosis, cardiogenic shock or previous bypass surgery were excluded. Survival analysis for MACE (death, recurrent myocardial infarction (MI), stroke) was performed using the log-rank test before and after stratification by combined syntax score of the non-culprit vessels. Results One hundred and nineteen patients with multivessel disease at index PCI for STEMI were included in the analysis (mean age 63.8 years (SD 12.8), male 81.5%, diabetes 13.4%, hypertension 35.3%, previous MI 18.5%, previous stroke 5.8%). Eighty-five (71%) patients underwent culprit only PCI and 34 (29%) underwent multivessel PCI. There were no differences in baseline variables between the two groups. Mean duration of follow up was 153.7 days (SD 137.4). MACE occurred in 14 patients from the culprit only PCI group (6 MI, 3 stroke and 6 deaths) while no events occurred in the multivessel PCI group (Figure 1). High syntax score (defined as >median) of the non-infarct vessels predicted increased MACE in the non-culprit PCI group (Figure 2). Conclusions In this single centre, retrospective analysis, multivessel PCI was associated with significantly improved clinical outcomes when compared to culprit only PCI in patients presenting with STEMI and multivessel disease. Our findings provide support for the results of recently published clinical trials.

Long-term results for treatment of patients with unprotected left main stenosis by CABG or PCI with Drug Eluting Stents. A prospective registry

Background: Up to the guidelines CABG is the prefered therapy for treatment of unprotected left main stenosis. Over the last decade a growing number of patients with this diagnosis have been treated by PCI. There are few long term results comparing both therapies. We present long-term result of a prospective registry of patients with unprotected left main stenosis treated by bypass revascularisation or PCI with drug eluting stents. Methods: From 04/2003 to 12/2010 1.590 patients with significant left main stenosis were recruited for the study. Patients with cardiogenic shock or acute myocardial infarction were excluded. The dedication of patients to the PCI- or CABG-group carried out at the discretion of the doctor particularly with regard to the baseline variables. Primary endpoint were death, stroke, acute myocardial infarction and reintervention. 246 patients were treated by PCI and 1.344 patients by CABG. There were significant differences in baseline characteristics with respect to age (72.0 vs 68.7 years), gender distribution, left ventricular function, NYHA-class and CCI-class between the PCI- and CABG group. No differences were seen in history of myocardial infarction, stroke, diabetes, hyperlipidemia, smoking and medication. Mean follow-up period was 3.8 years. We evaluated the results with propensity score analysis. Results: All patients received a complete revascularisation. We observed a low peri-interventional mortality of 0.4% in the PCI-group and 3.1% in the CABG-group. Over a cumulative period of 43 month, 24 pat. (12.4%) from the PCI-group and 228 pat. (21.0%) from CABG-cohort died. The stroke rate was 3.6% in both groups. 2.4% and 1.5% (PCI-/CABG-group) had a myocardial infarction. Target vessel revascularisation (TVR) rate was considerably higher for the PCI-cohort (23.9% vs 11.5%, p < 0.001). After adjustment of confounding variables there were no differences in the combined endpoint of death, stroke, myocardial infarction and TVR (p =0.092). For itemised endpoint analysis, only TVR was significant different to the disadvantage of PCI. There was a trend for lower mortality in the PCI-group (p=0.053). Conclusion: In patients with unprotected left main stenosis both CABG and PCI with DES can be performed with little procedural risk. Also for a longer follow up period of nearly 4 years, the rate for Death, Stroke and MI did not differ between PCI and CABG. TVR rate was significant higher in PCI group.

Acute Coronary Syndromes Presenting with Transient Diffuse ST Segment Depression and ST Segment Elevation in Lead aVR not Caused by “Acute Left Main Coronary Artery Occlusion”: Description of Two Cases

Diffuse ST-segment depression in the inferior + anterolateral leads with ST-segment elevation in lead aVR has been described as characteristic of diffuse circumferential subendocardial ischemia caused by acute subtotal occlusion of the left main coronary artery. Here we describe two patients admitted for acute neurological disorders who developed transient diffuse ST-segment depression in the inferior + anterolateral leads with ST-segment elevation in lead aVR, associated with elevation of cardiac troponin-I. In both cases subsequent coronary angiography did not show significant left main stenosis or "left main equivalent" narrowings. As both patients had acute neurological disorders, a possible association between the two conditions is discussed.

Guidelines on Diagnosis and Treatment of Stable Ischemic Heart Disease: Keeping Up With a Constantly Evolving Evidence Base

This issue includes guidelines from the American College of Physicians on the diagnosis and management of patients with SIHD. The editorialist discusses the complexity of the recommendations, how c...

Hybrid coronary revascularization for the treatment of left main coronary stenosis: A feasibility study

To determine the feasibility of a hybrid coronary revascularization (HCR) approach for the treatment of left main (LM) coronary artery stenosis. The recommended therapy for significant LM stenosis is coronary artery bypass grafting (CABG). Percutaneous coronary intervention (PCI) of unprotected LM lesions is reserved for patients at high risk for complications with CABG. HCR in LM disease has not been studied. Twenty-two consecutive patients with LM stenosis >70% underwent staged HCR. Following a robotic or thoracoscopic-assisted minimally invasive left internal mammary artery (LIMA) to left anterior descending artery (LAD) coronary bypass, PCI of the LM, and non-LAD targets was performed after angiographic confirmation of LIMA patency. Intravascular ultrasound confirmed optimal stent deployment. Thirty-day adverse outcomes and long term follow up was obtained. In the 22 patients with LM lesions, 6 were ostial, 5 mid, and 11 distal. LIMA patency was FitzGibbon A in all cases. LM stenting was successful in all patients with drug-eluting stents (DES) placed in 21 of 22 cases. Three patients underwent stent implantation in the right coronary artery. There were no 30-day major adverse cardiac or cerebrovascular events. At a mean of 38.8 ± 22 months postprocedure, 21 patients were alive without reintervention; one death occurred at 454 days. HCR for LM coronary disease is a feasible alternative to CABG and unprotected LM PCI. This approach combines the long-term durability of a LIMA-LAD bypass with the less invasive option of PCI in non-LAD targets with DES.

Epidemiology and clinical impact of different anatomical phenotypes of the left main coronary artery

Several studies have produced estimates of the outcome of percutaneous coronary intervention (PCI) in the field of left main (LM) coronary artery disease, but no research has been found that surveyed the issue of a comprehensive knowledge of LM anatomy and assessed the impact of different anatomic phenotypes on the likelihood of developing complications after LM PCI. We sought to develop a specific investigation on the basis of the regional anatomy and quantitative analysis of a large series of angiograms performed in our institution. We reviewed the baseline selective digital coronary angiographic examinations of 1,000 patients who did not undergo LM PCI and 296 patients with significant LM stenosis who did undergo PCI. All patients in both groups underwent a comprehensive qualitative and quantitative assessment of LM anatomical features according to several parameters. Hierarchical cluster analysis (HCA) was used to identify different anatomic phenotypes of the LM coronary artery. Three different anatomical patterns were identified by HCA. The proportion of patients with LM disease increased across clusters (19% in cluster 1, 27% in cluster 2 and 44% in cluster 3, p < 0.001). No differences were observed in terms of 18-month major adverse cardiac event-free survival among patients with LM disease undergoing PCI stratified by clusters (log rank p = 0.77). In conclusion, LM phenotypes can be identified that are more likely to present with atherosclerotic disease and significant stenosis.

Percutaneous Revascularization Is the Preferred Strategy for Patients With Significant Left Main Coronary Stenosis

In the early 1970s, coronary artery bypass graft (CABG) was found to improve late survival in comparison to medical therapy in patients with significant left main stenosis.1–3 Once CABG became the standard of care for left main disease, a distinction between “protected”—by at least 1 patent bypass graft to the left coronary artery—and “unprotected left main (UPLM)”— no patent bypass graft to the left coronary artery—was made. In the 1980s, early attempts at balloon angioplasty of UPLM stenoses were associated with poor early outcomes because of coronary dissection, abrupt closure, and restenosis. Mortality rates as high as 30% at 1 year were reported.4–6 In the 1990s, bare metal stents were introduced and soon used to treat UPLM disease. Several small registries found a low rate of procedural complications, but repeat revascularization rates of 20% to 30% because of restenosis were considered unacceptable.7–12 Early bare metal stent registries for UPLM also found high mortality rates, particularly in high-risk patients, such as patients with acute coronary syndromes and poor left ventricular function. Importantly, high-risk subgroups often presented with late sudden death after stenting.11,13 In the early 2000s, the introduction of drug-eluting stents (DES), with the promise of vastly reduced rates of restenosis,14–17 raised the possibility of improved late outcomes in this challenging patient group. Response by Smith p 1033 Clinical outcomes after treatment of UPLM disease with either the sirolimus-eluting stent or the paclitaxel-eluting stent from >20 small registries have been published. Results reported in these registries vary widely.18–40 As depicted in Table 1, cardiac mortality between 6 and 12 months after the procedure ranges from 0% to 11%. Target lesion revascularization (TLR) or target vessel revascularization (TVR) rates range from 2% to 38%. This wide variation in clinical outcome appears largely because of variation …