Survival in subgroups of patients with left main coronary artery disease. Veterans Administration Cooperative Study of Surgery for Coronary Arterial Occlusive Disease

Investigation of Myocardial Substrate for Sudden Arrhythmic Death in Coronary Artery Disease Without Acute Coronary Thrombosis or Myocardial Infarction

BACKGROUND

This cohort study aimed to evaluate the potential myocardial arrhythmic substrate in people with coronary artery disease who died from sudden arrhythmic death (SAD) without acute coronary thrombosis or myocardial infarction.

METHODS AND RESULTS

We performed histological analysis of the left ventricular free wall obtained at autopsy from decedents with ≥1 coronary artery and ≥75% area stenosis who died suddenly from either noncardiac causes (25 men, 23 women) or SAD (25 men, 25 women), matched for age and sex. Decedents with acute coronary thrombosis, myocardial infarction, or other myocardial abnormality were excluded. Decedents with either noncardiac death or SAD had similar height, weight, and heart weight. Decedents with SAD had higher cumulative area stenosis of coronary arteries (mean, 162% versus 134%; mean difference, 29% [95% CI, 1%-56%], P=0.042) and a higher proportion of decedents with SAD had diabetes (mean, 10% versus 0%; mean difference, 10% [95% CI, 2%-18%], P=0.025) and chronic, nonocclusive, organized coronary artery thrombus (mean, 16% versus 0%; mean difference, 16% [95% CI, 6%-26%], P=0.0040). Moreover, decedents with SAD had lower cardiomyocyte width (mean, 18.6 μm versus 19.6 μm; mean difference, 1.0 μm [95% CI, 0.2-1.8], P=0.014) and higher capillary length density (mean, 3618 mm/mm3 versus 3164 mm/mm3; mean difference, 453 mm/mm3 [95% CI, 210-697], P=0.0003) than decedents with noncardiac death.

CONCLUSIONS

SAD in people with coronary artery disease without acute coronary thrombosis or myocardial infarction was associated with greater coronary artery plaque burden and cardiomyocyte atrophy that may have contributed to myocardial substrate for arrhythmia.

Twenty Years of Experience in One Thousand De-Novo Left Main Coronary Angioplasty With Angiographic Control in a High-Volume Centre Without On-Site Cardiac Surgery

INTRODUCTION

Given the widespread use of percutaneous coronary intervention (PCI) for the treatment of unprotected left main coronary artery (ULMCA) disease, real-world data are needed to understand the current practice and identify pitfalls and potential benefits, especially for an older and frail population.

METHODS

We conducted a retrospective analysis including all patients, namely 1000, who underwent PCI on ULMCA for de-novo lesions, at our high-volume Italian center without on-site cardiac surgery, from 2002 to April 2023. Cases of restenosis, stent thrombosis, and coronary artery bypass grafting (CABG) were excluded. The primary clinical endpoint is major adverse cardiovascular and cerebrovascular event (MACCE), a composite endpoint including all-cause mortality, unplanned revascularization, myocardial infarction and stroke. Secondary clinical endpoints included the individual components of MACCE. Angiographic follow-up data, derived from both elective and clinical-driven procedures, were extensively available. The primary angiographic endpoint is target lesion failure (TLF), defined as significant restenosis or stent thrombosis of the LMCA. We performed a dedicated analysis comparing patients with a protocol-driven elective angiographic follow-up to those without, to evaluate the potential impact of this strategy on clinical outcomes.

RESULTS

Our registry encompasses a real-world frail and compromised population, with most patients (75%) presenting with acute coronary syndrome. Angiographic follow-up data were available for 739 patients (73.9%), of whom 612 (82.8%) demonstrated good results of the previous PCI and 127 patients (17.2%) experienced TLF. Multivariate analysis identified insulin-dependent diabetes, moderate to severe renal impairment, and a two-stents bifurcation technique as independent predictors of TLF. Among bifurcation techniques, the highest restenosis rates were observed in the Culotte technique (33.3%), followed by T and protrusion (30%) and Minicrush (28.2%), while the single stent approach was associated with the lowest rate of TLF (12.8%, p = < 0.001). Clinical follow-up data were available for 966 patients, with a survival rate of 95% at 7 days, 86.1% at 1 year, and 70% at an average follow-up of 2033 days. Multivariate analysis identified age over 70 years, moderate to severe renal impairment, multivessel disease, ejection fraction lower than 40%, hemodynamic instability (HDI) and endotracheal intubation (ETI) as independent predictors of MACCE and all-cause mortality while intravascular imaging was found to be protective for both. A propensity score matched analysis comparing two homogenous cohorts of 131 patients with and without elective angiographic follow-up demonstrated a significant survival advantage in the elective follow-up group, highlighting the potential benefits of this strategy.

CONCLUSIONS

In the real world setting clinical outcomes of PCI for unprotected LMCA disease are good and mainly affected by age, renal impairment, lower ejection fraction, multivessel disease and by the severity of the clinical presentation (namely HDI and ETI), while intravascular imaging was found to be protective. Notably, insulin-dependent diabetes and two-stent technique are independent predictors of TLF but not of mortality, while renal impairment has a negative impact on both. An elective angiographic follow-up could provide a survival benefit in this setting.

Mixed plaque on coronary CT angiography predicts atherosclerotic events in asymptomatic intermediate-risk individuals

OBJECTIVE

Coronary CT angiography (CCTA) permits both qualitative and quantitative analysis of atherosclerotic plaque and may be a suitable risk modifier in assessing patients at intermediate risk of atherosclerotic cardiovascular disease. We sought to determine the association of plaque components with long-term major adverse cardiovascular events (MACEs) in asymptomatic intermediate-risk patients, compared with conventional coronary artery calcium (CAC) score.

METHODS

100 intermediate-risk patients underwent double-blinded CCTA. Follow-up was conducted at 10 years and data were cross-referenced with the National Death Index. The primary outcome was MACE, which was a composite of death, acute coronary syndrome (ACS), revascularisation and stroke.

RESULTS

The median time from CCTA to follow-up was 9.5 years. 83 patients completed follow-up interview and mortality data were available on all 100 patients. MACE occurred in 17 (20.5%) patients, which included 2 (2%) deaths, 8 (10%) ACS, 3 (4%) strokes and 5 (6%) revascularisation procedures. 47 (57%) patients had mixed plaque, which was predictive of MACE (OR 4.68 (95% CI 1.19 to 18.5) p=0.028). The burden of non-calcified and mixed plaque, defined by non-calcified plaque segment stenosis score, was also a predictor of long-term MACE (OR 1.59 (95% CI 1.18 to 2.13) p=0.002). Neither calcified plaque (OR 3.92 (95% CI 0.80 to 19.3)) nor CAC score (OR 1.01 (95% CI 0.999 to 1.02)) was associated with long-term MACE.

CONCLUSION

The presence and burden of mixed plaque on CCTA is associated with an increased risk of long-term MACE among asymptomatic intermediate-risk patients and is a superior predictor to CAC score.

Revascularisation for Ischaemic Cardiomyopathy

Coronary artery disease is a leading cause of heart failure with reduced ejection fraction. Coronary artery bypass grafting appears to provide clinical benefits such as improvements in quality of life, reductions in readmissions and MI, and favourable effects on long-term mortality; however, there is a significant short-term procedural risk when left ventricular function is severely impaired, which poses a conundrum for many patients. Could percutaneous coronary intervention provide the same benefits without the hazard of surgery? There have been no randomised studies to support this practice until recently. The REVIVED-BCIS2 trial (NCT01920048) assessed the outcomes of percutaneous coronary intervention in addition to optimal medical therapy in patients with ischaemic left ventricular dysfunction and stable coronary artery disease. This review examines the trial results in detail, suggests a pathway for investigation and revascularisation in ischaemic cardiomyopathy, and explores some of the remaining unanswered questions.

Percutaneous Treatment of Left Main Disease: A Review of Current Status

Percutaneous treatment of the left main coronary artery is one of the most challenging scenarios in interventional cardiology, due to the large portion of myocardium at risk the technical complexity of treating a complex bifurcation with large branches. Our aim is to provide un updated overview of the current indications for percutaneous treatment of the left main, the different techniques and the rationale underlying the choice for provisional versus upfront two-stent strategies, intravascular imaging and physiology guidance in the management of left main disease, and the role of mechanical support devices in complex high-risk PCI.

Deferred Versus Performed Revascularization for Left Main Coronary Disease With Hemodynamic Significance

BACKGROUND

The majority of randomized controlled trials of revascularization decision-making excludes left main coronary artery disease (LMD). Therefore, contemporary clinical outcomes of patients with stable coronary artery disease and LMD with proven ischemia remain poorly understood. The aim of this study was to assess the long-term clinical outcomes of physiologically significant LMD according to the treatment strategies of revascularization versus revascularization deferral.

METHODS

In this international multicenter registry of stable LMD interrogated with the instantaneous wave-free ratio, patients with physiologically significant ischemia (instantaneous wave-free ratio ≤0.89) were analyzed according to the coronary revascularization (n=151) versus revascularization deferral (n=74). Propensity score matching was performed to adjust for baseline clinical characteristics. The primary end point was a composite of death, nonfatal myocardial infarction, and ischemia-driven target lesion revascularization of left main stem. The secondary end points were as follows: cardiac death or spontaneous LMD-related myocardial infarction; and ischemia-driven target lesion revascularization of left main stem.

RESULTS

At a median follow-up period of 2.8 years, the primary end point occurred in 11 patients (14.9%) in the revascularized group and 21 patients (28.4%) in the deferred group (hazard ratio, 0.42 [95% CI, 0.20-0.89]; P=0.023). For the secondary end points, cardiac death or LMD-related myocardial infarction occurred significantly less frequently in the revascularized group (0.0% versus 8.1%; P=0.004). The rate of ischemia-driven target lesion revascularization of left main stem was also significantly lower in the revascularized group (5.4% versus 17.6%; hazard ratio, 0.20 [95% CI, 0.056-0.70]; P=0.012).

CONCLUSIONS

In patients who underwent revascularization for stable coronary artery disease and physiologically significant LMD determined by instantaneous wave-free ratio, the long-term clinical outcomes were significantly improved as compared with those in whom revascularization was deferred.

National Institute for Health and Care Excellence guidelines on myocardial revascularisation

Cardiologists in the UK predominantly use the National Institute for Health and Care Excellence (NICE) and European Society of Cardiology guidelines to help guide decision-making. This article will appraise the current recommendations from NICE regarding myocardial revascularisation and compare them with other major international guidelines. While there are many similarities, subtle differences exist. These differences arise in part due to the evidence base at time of publication, as well as from the different healthcare systems that they are designed for, and from the cost-effectiveness models that dominate the methodology used by NICE. The clinical implications of the differences between the international guidelines will be analysed.

Left Main Disease

Traditionally, the treatment of left main coronary artery disease is recommended coronary artery bypass grafting because of its superior long-term outcomes compared with medical treatment and plain old balloon angioplasty. However, improvement of percutaneous coronary intervention technique and introduction of drug-eluting stent led to change of treatment strategy of left main coronary artery disease through cumulative data for revascularization that based on clinical evidence.

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.

2021 ACC/AHA/SCAI Guideline for Coronary Artery Revascularization: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The guideline for coronary artery revascularization replaces the 2011 coronary artery bypass graft surgery and the 2011 and 2015 percutaneous coronary intervention guidelines, providing a patient-centric approach to guide clinicians in the treatment of patients with significant coronary artery disease undergoing coronary revascularization as well as the supporting documentation to encourage their use.

METHODS

A comprehensive literature search was conducted from May 2019 to September 2019, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Collaboration, CINHL Complete, and other relevant databases. Additional relevant studies, published through May 2021, were also considered.

STRUCTURE

Coronary artery disease remains a leading cause of morbidity and mortality globally. Coronary revascularization is an important therapeutic option when managing patients with coronary artery disease. The 2021 coronary artery revascularization guideline provides recommendations based on contemporary evidence for the treatment of these patients. The recommendations present an evidence-based approach to managing patients with coronary artery disease who are being considered for coronary revascularization, with the intent to improve quality of care and align with patients' interests.

2021 ACC/AHA/SCAI Guideline for Coronary Artery Revascularization: Executive Summary: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The executive summary of the American College of Cardiology/American Heart Association/Society for Cardiovascular Angiography and Interventions coronary artery revascularization guideline provides the top 10 items readers should know about the guideline. In the full guideline, the recommendations replace the 2011 coronary artery bypass graft surgery guideline and the 2011 and 2015 percutaneous coronary intervention guidelines. This summary offers a patient-centric approach to guide clinicians in the treatment of patients with significant coronary artery disease undergoing coronary revascularization, as well as the supporting documentation to encourage their use.

METHODS

A comprehensive literature search was conducted from May 2019 to September 2019, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Collaboration, CINHL Complete, and other relevant databases. Additional relevant studies, published through May 2021, were also considered. Structure: Recommendations from the earlier percutaneous coronary intervention and coronary artery bypass graft surgery guidelines have been updated with new evidence to guide clinicians in caring for patients undergoing coronary revascularization. This summary includes recommendations, tables, and figures from the full guideline that relate to the top 10 take-home messages. The reader is referred to the full guideline for graphical flow charts, supportive text, and tables with additional details about the rationale for and implementation of each recommendation, and the evidence tables detailing the data considered in the development of this guideline.

2021 ACC/AHA/SCAI Guideline for Coronary Artery Revascularization: Executive Summary: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

The executive summary of the American College of Cardiology/American Heart Association/Society for Cardiovascular Angiography and Interventions coronary artery revascularization guideline provides the top 10 items readers should know about the guideline. In the full guideline, the recommendations replace the 2011 coronary artery bypass graft surgery guideline and the 2011 and 2015 percutaneous coronary intervention guidelines. This summary offers a patient-centric approach to guide clinicians in the treatment of patients with significant coronary artery disease undergoing coronary revascularization, as well as the supporting documentation to encourage their use.

METHODS

A comprehensive literature search was conducted from May 2019 to September 2019, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Collaboration, CINHL Complete, and other relevant databases. Additional relevant studies, published through May 2021, were also considered.

STRUCTURE

Recommendations from the earlier percutaneous coronary intervention and coronary artery bypass graft surgery guidelines have been updated with new evidence to guide clinicians in caring for patients undergoing coronary revascularization. This summary includes recommendations, tables, and figures from the full guideline that relate to the top 10 take-home messages. The reader is referred to the full guideline for graphical flow charts, supportive text, and tables with additional details about the rationale for and implementation of each recommendation, and the evidence tables detailing the data considered in the development of this guideline.

Forward-viewing estimation of 3D blood flow velocity fields by intravascular ultrasound: Influence of the catheter on velocity estimation in stenoses

Coronary artery disease is the most common type of cardiovascular disease, affecting > 18 million adults, and is responsible for > 365 k deaths per year in the U.S. alone. Wall shear stress (WSS) is an emerging indicator of likelihood of plaque rupture in coronary artery disease, however, non-invasive estimation of 3-D blood flow velocity and WSS is challenging due to the requirement for high spatial resolution at deep penetration depths in the presence of significant cardiac motion. Thus we propose minimally-invasive imaging with a catheter-based, 3-D intravascular forward-viewing ultrasound (FV US) transducer and present experiments to quantify the effect of the catheter on flow disturbance in stenotic vessel phantoms with realistic velocities and luminal diameters for both peripheral (6.33 mm) and coronary (4.74 mm) arteries. An external linear array ultrasound transducer was used to quantify 2-D velocity fields in vessel phantoms under various conditions of catheter geometry, luminal diameter, and position of the catheter relative to the stenosis at a frame rate of 5000 frames per second via a particle imaging velocimetry (PIV) approach. While a solid catheter introduced an underestimation of velocity measurement by > 20% relative to the case without a catheter, the hollow catheter introduced < 10% velocity overestimation, indicating that a hollow catheter design allowing internal blood flow reduces hemodynamic disturbance. In addition, for both peripheral and coronary arteries, the hollow catheter introduced < 3% deviation in flow velocity at the minimum luminal area compared to the control case. Finally, an initial comparison was made between velocity measurements acquired using a low frequency, catheter-based, 3-D intravascular FV US transducer and external linear array measurements, with relative error < 12% throughout the region of interest for a flow rate of 150 mL/min. While further system development is required, results suggest intravascular ultrasound characterization of blood flow velocity fields in stenotic vessels could be feasible with appropriate catheter design.

Towards a common pathway for the treatment of left main disease: contemporary evidence and future directions: Left main disease treatment

There is increasing evidence to support percutaneous treatment of left main (LM) disease. Due to its major clinical impact, any procedure in the left main should be meticulously planned and performed. In this review, we aim to integrate the available evidence into a common treatment pathway, starting with understanding the distinct anatomical features of the left main. A three-level decision-making process is presented. First, in instances of angiographic ambiguity, intravascular ultrasound and fractional flow reserve can be used to decide if revascularisation could be deferred. Second, if revascularisation is indicated, the risks and benefits of percutaneous versus surgical procedures should be evaluated. Third, if percutaneous coronary intervention (PCI) is chosen, the operator should decide between the provisional single-stent versus upfront two-stent strategies. Regardless of the PCI technique selected, it should be performed according to the recommendations of a stepwise procedure utilising proximal optimisation (POT) after each instance of crossover stenting and kissing balloon inflation (KBI) where necessary. In addition to the recognised quality markers such as POT and KBI, we discuss the clinical relevance of the operator's LM PCI experience and the intracoronary imaging guidance when treating patients with left main disease.

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

BACKGROUND

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSION

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

Percutaneous Coronary Intervention or Surgery for Unprotected Left Main Disease: EXCEL Trial at 5 Years

Although coronary artery bypass graft (CABG) surgery traditionally has been considered the gold standard for left main revascularization, percutaneous coronary intervention has evolved in the past decades so that it now represents a valid alternative to CABG in a large proportion of cases. The landmark Evaluation of XIENCE versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization (EXCEL) trial is the largest contemporary randomized comparison assessing the impact of revascularization strategies for left main disease. This review discusses the background, rationale, design, results, and implications of the EXCEL trial.

Applicability and Eligibility of the International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA) for Patients who Underwent Revascularization with Percutaneous Coronary Intervention

In the International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA) trial, an early invasive strategy did not decrease mortality compared to a conservative strategy for stable ischemic heart disease (SIHD) patients with moderate-to-severe ischemia, and the role of revascularization would be revised. However, the applicability and potential influence of this trial in daily practice remains unclear. Our objective was to assess the eligibility and representativeness of the ISCHEMIA trial on the patients with percutaneous coronary intervention (PCI). From a multicenter registry, we extracted a consecutive 13,223 SIHD patients with PCI (baseline cohort). We applied ISCHEMIA eligibility criteria and compared the baseline characteristics between the eligible patients and the actual study participants (randomized controlled trial (RCT) patients). In 3463 patients with follow-up information (follow-up cohort), the 2 year composite of major adverse cardiac events was evaluated between the eligible patients and RCT patients, as well as eligible and non-eligible patients in the registry. In the baseline cohort, 77.3% of SIHD patients with moderate-to-severe ischemia were eligible for the ISCHEMIA. They were comparable with RCT patients for baseline characteristics and outcomes unlike the non-eligible patients. In conclusion, the trial results seem applicable for the majority of PCI patients with moderate-to-severe ischemia except for the non-eligible patients.

Left Main Coronary Artery Disease and Outcomes after Percutaneous Coronary Intervention for Chronic Total Occlusions

Background: Concomitant left main coronary artery (LMCA) disease in patients with chronic total occlusions (CTO) commonly results in referral for coronary artery bypass grafting, although the impact of LMCA in CTO patients remains largely unknown. Nevertheless, patient selection for percutaneous coronary intervention of CTOs (CTO-PCI) or alternative revascularization strategies should be based on precise evaluation of the coronary anatomy to anticipate those patients that most likely benefit from a procedure and not on strict adherence to perpetual clinical practice. Therefore, the aim of this study was to assess the impact of LMCA disease on long-term outcomes in patients undergoing percutaneous coronary intervention for CTO. Methods: We enrolled 3860 consecutive patients undergoing PCI for at least one CTO lesion and investigated the predictive value of concomitant LMCA disease. All-cause mortality was defined as the primary study endpoint. Results: We observed that LMCA disease is significantly associated with mortality. In the Cox regression analysis, we observed a crude hazard ratio (HR) 1.59 (95% confidence interval (CI) 1.23–2.04, p < 0.001) for patients with LMCA disease as compared to patients without. Results remained unchanged after bootstrap- or clinical confounder-based adjustment. Conclusion: LMCA disease is associated with excess mortality in CTO patients. Specifically, anatomical features such as CTO of the circumflex artery represent a high risk patient population.

The association between left main coronary artery calcium and cardiovascular-specific and total mortality: The Coronary Artery Calcium Consortium

BACKGROUND AND AIMS

Left main (LM) coronary artery disease is associated with greater myocardial infarction-related mortality, however, coronary artery calcium (CAC) scoring does not account for disease location. We explored whether LM CAC predicts excess mortality in asymptomatic adults.

METHODS

Cause-specific cardiovascular and all-cause mortality was studied in 28,147 asymptomatic patients with non-zero CAC scores in the CAC Consortium. Multivariate regression was performed to evaluate if the presence and burden of LM CAC predict mortality after adjustment for clinical risk factors and the Agatston CAC score. We further analyzed the per-unit hazard associated with LM CAC in comparison to CAC in other arteries.

RESULTS

The study population had mean age of 58.3 ± 10 years and CAC score of 301 ± 631. LM CAC was present in 21.7% of the cases. During 312,398 patient-years of follow-up, 1,907 deaths were observed. LM CAC was associated with an increased burden of clinical risk factors and total CAC, and was independently predictive of increased hazard for all-cause (HR 1.2 [1.1, 1.3]) and cardiovascular disease death (HR 1.3 [1.1, 1.5]). The hazard for death increased proportionate to the percentage of CAC localized to the LM. On a per-100 Agatston unit basis, LM CAC was associated with a 6-9% incremental hazard for death beyond knowledge of CAC in other arteries.

CONCLUSIONS

The presence and high burden of left main CAC are independently associated with a 20-30% greater hazard for cardiovascular and total mortality in asymptomatic adults, arguing that LM CAC should be routinely noted in CAC score reports when present.

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.

Thrombotic/Thrombolytic Balance as a Cardiac Treatment Determinant in Patients With Diabetes Mellitus and Coronary Artery Disease

Background

This study aimed to assess whether the plasminogen activator inhibitor‐1/tissue plasminogen activator (PAI‐1/tPA) ratio as a prothrombotic state is useful for optimizing cardiac treatment strategy.

Methods and Results

Using BARI 2D (Bypass Angioplasty Revascularization Investigation 2 Diabetes) trial data, we used a Cox proportional hazard model to calculate hazard ratios with 95% CIs for cardiac events in patients receiving early revascularization (percutaneous coronary intervention or coronary artery bypass grafting) or medical therapy, separately in patients with low (n=1276) and high (n=894) PAI‐1/tPA ratios. The primary outcome was major cardiac events, which was a composite end point including cardiac death and nonfatal myocardial infarction. The mean±SD follow‐up period was 4.1±1.7 years. The risk of major cardiac events in patients with high PAI‐1/tPA ratio was significantly higher when receiving percutaneous coronary intervention (hazard ratio, 1.84; 95% CI, 1.16–2.93; P=0.01) than when receiving medical therapy, whereas that in patients with low PAI‐1/tPA ratio did not differ significantly between the groups (hazard ratio, 0.95; 95% CI, 0.66–1.36; P=0.77); the interaction between the cardiac treatment strategy and PAI‐1/tPA ratio was significant (P=0.02). However, regardless of the PAI‐1/tPA ratio, major cardiac event risk seemed to be lower in patients receiving coronary artery bypass grafting than in those receiving medical therapy.

Conclusions

In patients with type 2 diabetes mellitus and coronary artery disease, this study demonstrated that those with high PAI‐1/tPA ratio were at higher risks of major cardiac events when treated with percutaneous coronary intervention than when treated with intensive medical therapy.

Historical Milestones in the Management of Stable Coronary Artery Disease over the Last Half Century

Coronary revascularization for coronary artery disease dates back to the introduction of coronary bypass by Favaloro in 1967 and coronary angioplasty by Gruentzig in 1977 (first published in 1968 and 1978, respectively). There have been many technical improvements over the ensuing 5 decades, studied in clinical trials. This article reviews the history of coronary revascularization (the development of optimal medical therapy) and points the way to the future of stable coronary artery disease management.

Incidence, predictors, clinical profile, management and outcome of patients with isolated left main coronary artery ostial disease

Objectives

Isolated left main coronary artery (LMCA) ostial disease is a rare variant of LMCA disease. Earlier studies on this disease are limited by small number of patients enrolled. The aim of the present study was to analyze the incidence, risk factors, clinical profile and long term outcome of patients with isolated LMCA ostial disease.

Methods

15,553 patients who underwent coronary angiogram in a single tertiary care cardiac hospital were analyzed for LMCA disease. 351(2.2%) patients were found to have significant LMCA disease out of which 28(0.18%) had isolated LMCA ostial disease. These 28 patients were compared with 323 non-ostial and non-isolated LMCA disease patients.

Results

The mean age of isolated LMCA ostial disease group was significantly less than the other group (p=0.009). Females were more affected than males (p=0.008). They also had low incidence of coronary risk factors (especially dyslipidemia, p=0.04). They tend to present more with stable angina and less with myocardial infarction. They had higher ejection fraction and normal regional wall motion (p=0.04). There was no mortality difference between two groups at the end of 1 year (p=0.234).

Conclusion

In one of the largest studies done in these patients, we found that isolated LMCA ostial disease is more common in middle aged females with few coronary risk factors. These patients also had a better ejection fraction and normal regional wall motion compared to patients with non-ostial and non-isolated LMCA disease. The clinical and angiographic profile of these patients suggests that they may represent a distinct clinical entity.

The Current State of Left Main Percutaneous Coronary Intervention

PURPOSE OF REVIEW

While coronary artery bypass grafting (CABG) remains the standard of care, advances in stenting technology and procedural technique are changing the role of percutaneous coronary intervention (PCI) in the treatment of severe left main coronary artery (LMCA) disease. We review contemporary evidence comparing PCI and CABG for the treatment of severe LMCA disease, discuss optimal techniques during left main PCI, and provide guidance on studied revascularization strategies within specific patient subgroups.

RECENT FINDINGS

Results from randomized control trials of patients treated with PCI or CABG for severe LMCA disease demonstrate comparable short- and mid-term rates of death, myocardial infarction (MI), and stroke, but increased rates of repeat or target-vessel revascularization after PCI. Though extended follow-up data has suggested lower long-term rates of MI and stroke in patients with severe LMCA disease treated with CABG, results from patients undergoing PCI with second-generation drug-eluting stents (DES) demonstrate non-inferiority in these outcomes. These findings are generalizable to patients with severe LMCA disease having low to intermediate anatomic complexity. Intravascular ultrasound and double kissing (DK) crush stenting also reduce adverse event rates among patients undergoing left main PCI and improve long-term outcomes. In patients with severe LMCA disease having low to intermediate anatomic complexity, both CABG and PCI with second-generation DES are effective methods of revascularization with comparable long-term rates of death, MI, and stroke. The roles of multi-vessel coronary artery disease and anatomic complexity on long-term outcomes after CABG or PCI for severe LMCA disease remain under investigation.

Meta-Analysis of Comparison of 5-Year Outcomes of Percutaneous Coronary Intervention Versus Coronary Artery Bypass Grafting in Patients With Unprotected Left Main Coronary Artery in the Era of Drug-eluting Stents

Patients with unprotected left main coronary artery (ULMCA) disease are increasingly being treated with percutaneous coronary intervention (PCI) using drug-eluting stents (DES), but long-term outcomes comparing PCI with coronary artery bypass grafting (CABG) remain limited. We performed aggregate data meta-analyses of clinical outcomes (all-cause death, nonfatal myocardial infarction, stroke, repeat revascularization, cardiac death, and major adverse cardiac and cerebrovascular events) in studies comparing 5-year outcomes of PCI with DES versus CABG in patients with ULMCA disease. A comprehensive literature search (January 1, 2003 to December 10, 2016) identified 9 studies (6,637 patients). Effect size for individual clinical outcomes was estimated using odds ratio (OR) with 95% confidence intervals (CI) using a random effects model. At 5 years, PCI with DES was associated with equivalent cardiac (OR 0.95, 95% CI 0.62 to 1.46) and all-cause mortality (OR 0.98, 95% CI 0.72 to 1.33), lower rates of stroke (OR 0.50, 95% CI 0.30 to 0.84), and higher rates of repeat revascularization (OR 2.52, 95% CI 1.63 to 3.91); compared with CABG, major adverse cardiac and cerebrovascular events showed a trend favoring CABG but did not reach statistical significance (OR 1.19, 95% CI 0.93 to 1.54). In conclusion, for ULMCA disease, PCI can be considered as a comparably effective and yet less invasive alternative to CABG given the comparable long-term mortality and lower incidences of stroke.

Effect of Percutaneous Coronary Intervention on Survival in Patients with Stable Ischemic Heart Disease

PURPOSE OF REVIEW

This study aims to determine if percutaneous coronary intervention (PCI) does improve survival in stable ischemic heart disease (SIHD).

RECENT FINDINGS

The International Study of Comparative Health Effectiveness with Medical and Invasive Approaches (ISCHEMIA) trial will evaluate patients with moderate to severe ischemia and will be the largest randomized trial of an initial management strategy of coronary revascularization (percutaneous or surgical) versus optimal medical therapy alone for SIHD. Although the ISCHEMIA trial may show a benefit with upfront coronary revascularization in this high-risk population, cardiac events after PCI are largely caused by plaque rupture in segments outside of the original stented segment. Furthermore, given the robust data from prior randomized trials, which showed no survival benefit with PCI, and the likelihood that the highest risk patients in ISCHEMIA will be treated with surgery, it is unlikely that the ISCHEMIA trial will show a survival benefit particular to PCI.

RECENT FINDINGS

Although PCI relieves symptoms, the evidence base indicates that it does not prolong survival in SIHD.

Meta-Analysis Comparing Coronary Artery Bypass Grafting to Drug-Eluting Stents and to Medical Therapy Alone for Left Main Coronary Artery Disease

Historically, coronary artery bypass graft (CABG) surgery has been the standard revascularization method for unprotected left main coronary artery (LMCA) disease. Over the last decade, several randomized controlled trials (RCTs) have shown favorable results for percutaneous coronary intervention (PCI) with drug-eluting stent (DES) compared with CABG; however, no RCT has been conducted directly comparing DESs with medical therapy alone (MTA). Furthermore, the 2 most recently reported larger RCTs, using new-generation DESs reached somewhat conflicting conclusions comparing the 2 revascularization strategies. Therefore, we performed a traditional pairwise meta-analysis and Bayesian network meta-analysis to compare the efficacies of the 3 currently available treatment strategies (MTA, CABG, and DES) for unprotected LMCA disease. Scientific databases and websites were searched to find RCTs. Data from 8 trials including 4,850 patients were analyzed. Overall PCI increased the risk of major adverse cardiac and cerebrovascular events (MACCEs) driven by increased rate of revascularization compared with CABG, but no differences in all-cause mortality, cardiac mortality, and recurrent myocardial infarction were found. However, early (i.e., within 30 days) PCI decreased the risk of MACCEs and stroke compared with CABG. In the mixed-treatment comparison models, both CABG and DESs were associated with better survival compared with MTA, but no difference was found between them. In conclusion, in patients with unprotected LMCA disease, PCI with DESs yields similar all-cause and cardiac mortalities compared with CABG. Furthermore, CABG increases early (i.e., within 30 days) MACCE rates, driven by an increased risk of stroke. Over longer durations, PCI increases MACCE rates because of increased recurrent revascularization.

Study of Short and Intermediate Term Clinical Outcomes of Patients with Protected and Unprotected LMCA Stenting

INTRODUCTION

Significant unprotected Left Main Coronary Artery (LMCA) disease is detected in 5%-7% of cases undergoing Coronary Angiography (CAG). Present guidelines have revealed the significance of anatomical location in left main artery stenosis and syntax scores for determination of Major Adverse Cardiac Events (MACE). Debate still persists over the best treatment regarding outcomes of Coronary Artery Bypass Grafting (CABG) and LMCA stenting for patients with LMCA disease.

AIM

Aim of the study was to evaluate short and intermediate term clinical outcomes of Percutaneous Coronary Intervention (PCI) in LMCA disease in respect to mortality, Cerebrovascular Accidents (CVA), reinfarction, stent restenosis and need for repeat target lesion revascularization.

MATERIALS AND METHODS

From July 2013 to February 2015, 50 patients underwent LMCA stenting. All patients underwent detailed clinical assessment, detailed 2D echocardiographic assessment. Syntax score was calculated in all patients. Clinical in hospital and outpatient follow up was obtained at one, three, six, nine months and one year.

RESULTS

Mean age was 53.14±9.60 years. On CAG 16 (32%) patients had ostial LMCA lesion, 8 (16%) had mid LMCA lesion, distal LMCA was diseased in 6 (12%). In emergency situation, two bail out LMCA stenting were done for treatment of LMCA dissection. A total of 42 (84%) patients had low syntax score, 6 (12%) had intermediate and 2 (4%) had high syntax score. Only LMCA stenting was done in 22 (44%) patients, LMCA to Left Anterior Descending (LAD) stenting was done in 22 (44%) and LMCA to Left Circumflex (LCX) stenting was done in 6 (12%) patients. Drug-Eluting Stent (DES) was used in 35 (70%) cases while Bare-Metal Stent (BMS) was used in 15 (30%). An 8% mortality and 8% target lesion revascularization rate were observed in our study.

CONCLUSION

Our study revealed that LMCA stenting is a safe and feasible alternative mode of revascularization in selected patients. Patients most suitable for LMCA stenting in our study were those with isolated ostial/mid LMCA disease, with protected LMCA disease and those who underwent elective stenting procedure.

Isolated and Significant Left Main Coronary Artery Disease: Demographics, Hemodynamics and Angiographic Features

Left main coronary artery disease carries a poor prognosis. The etiology of isolated and significant left main coronary artery (ILMCA) disease is not well understood. Studies so far were limited by small numbers. The authors identified 46 patients with ILMCA disease from their database over 10 years (group I) and compared them with 83 consecutive patients undergoing catheterization (group II). They also compared patients with ostial vs distal ILMCA disease. Group I represented 0.1% of catheterization patients. The demographic profile and atherosclerotic risk factor profile of the 2 groups as well as ostial and distal ILMCA disease were compared. This is the largest study of ILMCA disease. Risk factors for atherosclerosis were commonly seen. Nonatherosclerotic causes of ILMCA disease were not seen. This study suggests coronary atherosclerosis as the predominant cause of ILMCA disease. ILMCA disease is more common in women. Diabetes is more commonly associated with distal ILMCA lesion. There is a trend suggesting that ostial ILMCA lesion is more common in smokers and women.

Retrograde Coronary Sinus Perfusion for Severe Left Main Stenosis

Between April 1996 through March 1999, 15 patients with severe (> 60%) left main coronary artery stenosis became hemodynamically unstable on induction of anesthesia, in spite of optimal pharmacological management. Retrograde coronary sinus perfusion was instituted soon after the median sternotomy to improve hemodynamics until the establishment of cardiopulmonary bypass after harvesting internal mammary artery and saphenous vein grafts.

Angioplasty of unprotected left main coronary stenosis: Real world experience of a single-operator group from eastern India

Background

Coronary artery bypass graft surgery is the standard treatment of unprotected left main coronary stenosis (ULMCA). However, in the real world scenario, many of these patients are unfit for CABG or prefer angioplasty as an alternative when offered the choice.

Methods

A total of 86 clinically stable patients with ULMCA stenosis who were unfit or unwilling for CABG underwent PCI with DES at two tertiary care centers in Kolkata. Patients were followed up prospectively for a median of 34.6 months for major adverse cardiovascular events. Angiographic follow-up was done after 1 year of index procedure or earlier, if indicated.

Results

Fifty-five patients (64%) had distal left main stenosis. Two-stent technique was used in 19 patients (22%) and single-stent technique in 36 patients (42%) with distal left main lesion. Thirteen patients (15.1%) had left ventricular ejection fraction (LVEF) of ≤45%. There was no in-hospital death, MI, or stent thrombosis. During follow-up, major adverse cardiac event (MACE) occurred in 9 patients (10.5%). Our study revealed significantly greater MACE in patients with distal left main lesion with LVEF ≤45% (50% vs 6.38%, p = 0.0002), high SYNTAX score (36.36% vs 6.82%, p = 0.008), and diabetes (17.95% vs 0.00%, p = 0.07). Overall, also patients with Diabetes, LVEF ≤ 45%, and SYNTAX score >32 had significantly higher MACE. Use of IC Stent, IVUS, or procedural strategy in distal lesion did not affect MACE.

Conclusion

In selective patients with low-intermediate SYNTAX score and without diabetes and LV dysfunction, ULMCA PCI with DES is feasible.