SCAI position statement on optimal percutaneous coronary interventional therapy for complex coronary artery disease

The anatomic and clinical complexity of patients with coronary artery disease (CAD) is increasing in the United States.1-3 While the terms "complex CAD" or "high-risk CAD" have not been formally defined, they encompass both complex anatomic lesions and clinical parameters including advanced age, frailty, comorbidities, compromised hemodynamic status, depressed ventricular function and concomitant valvular disease.4-6 Such features increase both the procedural complexity of percutaneous coronary intervention (PCI) and the risk of adverse patient outcomes. The direct relationship between CAD complexity and the appropriateness for coronary revascularization is also emphasized in current societal guidelines and appropriate use criteria documents; however, precise guidance for managing this growing patient group is lacking.7-9 In this document, the Society for Cardiovascular Angiography and Interventions (SCAI) has produced an expert consensus with a two-fold objective: (a) to present state-of-the art clinical evidence regarding PCI in patients with complex clinical and anatomical features, and (b) to provide procedural guidance to achieve optimal outcomes for this challenging patient group. This is a companion document to the jointly published SCAI statement on the performance of PCI in ambulatory surgical centers (ASC).177 Together these documents aim to provide guidance on best practices and the performance settings for PCI across the spectrum of clinical and anatomical complexity (Figure 1). Below, we first discuss pre-procedural risk stratification for complex CAD patients, and then detail the best interventional practices for specific complex coronary lesion subsets. This document was developed according to SCAI Publications Committee policies for writing group composition, disclosure and management of relationships with industry, internal and external review, and organizational approval.10 The need for a SCAI position paper on treating complex CAD was identified by a working group from the SCAI Executive Committee and Ischemic Heart Disease Council. By design, the writing group included a group of multidisciplinary physicians who care for patients with complex CAD, including interventional cardiologists, general cardiologists specialized in noninvasive imaging, and cardiothoracic surgeons. Before the appointment, members of the writing group were asked to disclose financial relationships from the 12 months prior to the nomination (Table S1). A majority of the writing group disclosed no relevant financial relationships. Disclosures were periodically reviewed during document development and updated as needed. SCAI policy requires that writing group members with a current relevant financial interest are recused from participating in discussions or voting on relevant recommendations. The work of the writing committee was supported exclusively by SCAI, a nonprofit medical specialty society, without commercial support. This document primarily reflects expert consensus opinion. The draft manuscript was peer reviewed in April 2020 and the document was revised to address pertinent comments. The writing group unanimously approved the final version of the document. The SCAI Publications Committee and Executive Committee endorsed the document as official society guidance in May 2020. Defining a coronary interventional procedure as "complex" or "high-risk" usually integrates several risk domains, including both the clinical risk profile of the patient and the technical complexity of the intervention(s) planned (Figure 2). To go beyond the subjectivity inherent in clinical judgment, multiple methods have been validated to objectively assess patient risk prior to coronary revascularization. Clinical risk scores such as the society of thoracic surgeons (STS) score, EuroSCORE II, National Cardiovascular Data Registry (NCDR), and others can provide insights into the risk of procedural complications.11-13 In addition, integrated anatomical-clinical scores such as the Synergy Between PCI with Taxus and Cardiac Surgery (SYNTAX) II score provide additional value by assessing the comparative 4-year mortality rates of PCI and coronary artery bypass grafting (CABG) surgery.5 Current ACC/AHA guidelines recommend calculation of a STS and SYNTAX score for patients with complex CAD or unprotected left main (LM) disease.7 For multivessel or LM CAD, the utilization of a heart team to guide decision-making for optimal revascularization is a Class I recommendation from both the American and European guidelines.8, 14 As interventional cardiologists, cardiac surgeons, heart failure specialists, and other cardiologists offer different treatment perspectives, integrated decision-making can facilitate patient-centered revascularization. Group discussions can center around patient-specific presentation and comorbidities, calculation of various risk scores, and implementation of society guideline recommendations to facilitate decision-making. Moreover, a heart team approach may provide better outcomes, as suggested by favorable outcomes in the registry arms of randomized controlled trials and routine clinical practice.15-17 Recent evidence further shows that utilizing a structured heart team form and a formal interventional cardiology consultative service can improve the operation of a CAD heart team.18 Therefore, the use of the CAD heart team is encouraged for guiding revascularization decision-making for patients with complex CAD. In certain situations, PCI-based management of complex CAD may require advanced approaches such as atherectomy, chronic total occlusion (CTO) PCI capabilities, temporary or durable mechanical circulatory support, or the availability of on-site cardiac surgery. If such an approach is potentially indicated but not available at the initially planned PCI center, arrangements should be made to refer or transfer patients to a PCI center equipped with these capabilities. Collaboration with other specialized interventional cardiologists with expertise in complex PCI to discuss more complicated PCI scenarios is therefore encouraged to provide optimal outcomes for complex PCI patients. Multivessel CAD is common in patients undergoing high-risk, complex PCI.19 Multiple observational studies of both CABG and PCI demonstrate that completeness of revascularization is associated with improved outcomes among patients with multivessel disease.20-22 However, randomized trial data supporting complete revascularization is only available for ST-elevation myocardial infarction (STEMI) patients undergoing primary PCI, where complete revascularization of significant nonculprit lesions reduces cardiovascular events.21, 23 If complete revascularization by PCI is indicated, a careful assessment of the risk and benefit of this approach is required to optimize patient safety. For patients with multivessel disease, this may require noninvasive ischemia or viability testing, invasive coronary physiologic testing, and considering staged revascularization to reduce the risk of any single procedure.22, 24, 25 Utilizing state-of-the-art PCI techniques including intravascular imaging and physiology, discussed in detail below, leads to excellent outcomes for patients with complex CAD including CTO, multivessel and LM lesions.5 A significant proportion of patients with complex CAD may be at prohibitive risk for complications with CABG. While the STS risk calculator may be useful in determining the expected complication and mortality rate with CABG, it is less useful in guiding the decision between PCI and CABG. The SYNTAX II score was created to help define the optimal revascularization strategy (CABG vs. PCI) for individual patients based on coronary anatomy and select comorbidities.26 This score, which can be used in conjunction with a multidisciplinary heart team approach, may provide a highly evidence-based approach to determine the relative merits of PCI, CABG, hybrid strategies, or medical therapy in patients with multivessel disease.18 Patients with multivessel or LM coronary disease declined for cardiac surgery based on high surgical risk and/or severe medical comorbidities represent a particularly high-risk subgroup of patients referred for PCI. These patients have an increased risk of mortality out of proportion to the risk assessed by traditional PCI risk stratification tools.9, 27 Randomized clinical trials comparing different revascularization strategies for such patients are lacking. The combination of the potentially high technical complexity of PCI and compromised ability to tolerate sustained ischemia or complications make a multidisciplinary evaluation particularly valuable in such patients. PCI reduces morbidity and mortality in acute coronary syndromes (ACS), in patients with or without ST-segment elevation.28, 29 Minimizing the time to reperfusion is critical in STEMI and requires coordinated transfer systems and early activation of the cardiac catheterization laboratory.30, 31 Additionally, an early invasive strategy is preferred for non-STEMI patients, especially for those at higher risk.29, 32 However, PCI in ACS patients is associated with higher adverse event rates compared with elective PCI. Adjunctive antiplatelet and anticoagulant therapy can help reduce the procedural risk. Furthermore, complete revascularization in the presence of multivessel CAD is associated with improved long-term clinical outcomes in STEMI.21, 23 Whether complete revascularization should be performed in patients with non-STEMI remains unknown, but maybe supported by observational data.33 Staging procedures for the treatment of non-culprit stenoses appears to be safe if performed in a timely fashion.34 Surgical revascularization in addition to optimal medical therapy in patients with impaired left ventricular (LV) function (EF <= 35%) has been shown to reduce all-cause mortality compared to medical therapy alone.35, 36 Additionally, PCI in the setting of STEMI and concurrent cardiogenic shock has been shown to reduce long-term mortality.37 However, performing PCI in patients with impaired LV function is associated with higher mortality rates, likely due to lack of myocardial reserve.38 MCS devices, particularly ventricular axial and centrifugal flow devices, aim to improve the safety and efficacy of PCI in patients at very high-risk for revascularization. This includes elective complex and high-risk procedures, emergent revascularization for acute myocardial infarction (AMI), and acute decompensated heart failure complicated by cardiogenic shock.4, 39-42 Several proposed algorithms to guide the use of MCS incorporate the anatomic complexity of CAD, area of myocardium to be treated or at risk, estimated procedural duration, planned technical interventional strategies, underlying LV dysfunction, cardiac and systemic hemodynamic state, degree of cardiogenic shock, and major medical comorbidities and surgical eligibility.9, 39, 40, 43 Device selection is further guided by the ease of implantation and use, vascular complication risks, mechanism and degree of circulatory support, device and patient-specific contraindications, patient acuity and disease severity, anticipated duration of support and operator/center-specific procedural volume and expertise (Figure 3).39, 40 Heart team management decisions should also weigh the relative risks and benefits of both MCS-assisted and unassisted PCI compared with available surgical therapeutic options including surgical revascularization, durable LV assist device implantation, and heart transplantation. Appropriate patient selection is particularly critical in light of the potential for device-related complications.44-46 There are limited randomized data for elective and emergent use of MCS devices during complex PCI procedures. Observational studies demonstrate improved procedural cardiovascular hemodynamics and more complete revascularization in the presence of MCS devices despite higher-risk patient profiles. In select patients with ischemic cardiomyopathy, PCI with MCS can also improve LV function.47 However, limitations of routinely using this strategy include device-specific learning curves and variable device-related complication rates.48-51 Low-dose contrast peripheral angiography, arterial duplex scans, or computed tomography angiography may be useful for preprocedural planning in patients with suspected or known peripheral arterial disease that may require MCS support. There is an inverse relationship between eGFR and the incidence of CAD.52 Furthermore patients with chronic kidney disease (CKD) experience a 2–3-fold higher risk of mortality from CAD.53 However, diagnostic angiography and coronary revascularization are underutilized in patients with CKD and end-stage renal disease on dialysis, illustrating a risk-treatment paradox.53, 54 This is in part due to the elevated risk of contrast-induced acute kidney injury (CIAKI) and the complexity of diffuse, calcific CAD often encountered among CKD patients. There is a direct relationship between the amount of contrast delivered during coronary angiography/PCI and the risk for CIAKI.55 However, intravascular volume-administration of normal saline guided by invasively measured filling pressures can reduce the risk of CIAKI.56 Ultra-low contrast diagnostic angiography based upon calculated eGFR should also be considered, with the volume of the maximum allowed contrast target ideally less than the eGFR.57 If PCI is indicated, this can either be performed in the same setting or be staged. Regardless of the setting, minimizing contrast volume to eGFR ratio of ≤ 2.0–3.7, has been shown to reduce the risk of CIAKI.58-60 Contrast use during PCI can be further reduced by liberal use of intravascular imaging and/or physiology assessment to guide PCI.61 Initial diagnostic images should be used to guide PCI to reduce the need for additional angiography at the time of PCI and coregistration with imaging catheters and/or road mapping software to mark the proximal and distal edges of the lesion with dry cineangiography can further reduce the usage of contrast.62 Concomitant significant mitral and/or aortic valvular heart disease is not infrequent in patients with complex CAD and patients with both conditions have increased cardiovascular mortality compared with either entity in isolation.63-65 Percutaneous MCS devices may be indicated during high-risk PCI in patients with significant valve disease due to their lower tolerance of cardiac ischemia. A multidisciplinary heart team approach is essential to evaluate this patient group to optimize the timing of coronary revascularization and valvular intervention. For patients undergoing percutaneous treatment of both obstructive CAD and severe aortic stenosis, the optimal timing of PCI and transcatheter aortic valve replacement (TAVR) remains unknown. A staged approach with revascularization of significant CAD prior to TAVR may reduce the risk of the TAVR procedure and minimize issues related to coronary accessibility post-TAVR.64 However, some studies have suggested that simultaneous PCI and TAVR have lower 30-day mortality as compared with staged PCI and TAVR.66 In patients with concomitant CAD and mitral valve (MV) disease, a hybrid approach with PCI and a minimally invasive MV intervention may reduce mortality and mobility.67, 68 Further studies are indicated to understand how to best manage this challenging patient subset. CABG is the guideline-recommended choice of revascularization in patients with diabetes mellitus presenting with multivessel or LM CAD and average surgical risk.8, 31, 69, 70 However, some patients may have high surgical risk, poor targets, and/or poor conduits for surgical grafts. In addition, some patients may prefer a percutaneous approach. In such cases, PCI or even a minimally-invasive hybrid revascularization approach may be appropriate.71 Patients with diabetes who undergo PCI experience higher rates of periprocedural adverse events as well as stent restenosis, as compared with non-diabetics.11 It is postulated that increased events occur due to a prothrombotic state, increased resistance to antiplatelet therapies, more diffuse atherosclerosis, and negative vessel remodeling.72-74 Additionally, patients with diabetes requiring treatment with insulin and/or with poorly controlled hyperglycemia experience even higher event rates.75, 76 To achieve optimal outcomes following revascularization, excellent glycemic control is needed, with consideration of newer pharmacotherapies that have been shown to improve cardiovascular outcomes.77 Radial access is associated with similar technical and procedural success compared to femoral access and often offers lower risks of major bleeding and vascular complications.78-80 Complex interventions including LM bifurcations, CTO PCI, and large burr atherectomy may now be performed safely and effectively via the radial artery with standard or sheathless guide catheters up to eight French in size, and incorporating additional support strategies that include guide catheter extensions and anchor balloons.79, 81 Evidence also suggests that when necessary, femoral access may still be performed safely by expert operators using optimal ultrasound-guided access, including the use of micropuncture needles.82-85 Multiple arterial access sites are often needed for CTO PCI or adjunctive MCS device use during complex PCI, thereby increasing the periprocedural risks of bleeding, vascular and These may be by the use of radial or artery access as the radial access, or femoral techniques for MCS-assisted Radial access with newer peripheral may also be in both and complications during femoral Percutaneous or implantation of MCS devices have also been proposed as safe and in of prohibitive femoral arterial access among select The of periprocedural systemic is to reduce acute and ischemic procedural complications minimizing and are indicated for PCI periprocedural the lack of in large randomized trials of complex PCI, remains the of therapy in this This is likely related to the ease of periprocedural using time in of and In the and of in Percutaneous Patients an value of was associated with the ischemic and bleeding complication rates, and high are for procedures devices in the for CTO is an for patients with or a particularly high bleeding Patients presenting with an ACS should be ideally with antiplatelet therapy For ACS patients not with adjunctive or can be regarding the of treatment are discussed physiology and imaging are adjunctive procedures used in and optimal revascularization in patients with complex CAD. Angiography often lesion and hemodynamic that lesions that initially significant may not and To achieve optimal CAD and PCI outcomes, the to be in physiology and intravascular imaging performance and assessment of coronary lesions flow or such as ratio ratio ratio ratio is an of revascularization in patients with complex CAD. These help determine which lesions are significant and especially when noninvasive is or The use of coronary physiology to guide complex PCI a risk and the technical during PCI, and clinical outcomes (Table For has been used to the risk in patients with multivessel CAD compared to angiography Additionally, is particularly in LM disease, where the of significant or can be imaging using intravascular or tomography can help during angiography, assess the degree of and and facilitate PCI vessel Additionally, PCI long-term clinical outcomes (Table is critical in guiding the and treatment of stent which is due to stent In addition, the clinical and complex of the LM coronary intravascular imaging is particularly valuable during LM imaging can also be useful during CTO PCI, from to stent and may be used to contrast use, which can be especially in high-risk patients with and LV lesions higher risks of both stent and due to stent The treatment of these lesions is also associated with increased risk of periprocedural including vessel device or vessel and higher periprocedural In addition, severe is associated with revascularization and higher risk of all-cause For these assessment is prior to PCI. In cases, adjunctive intravascular imaging or preprocedural computed tomography can be to help assess the degree of lesion Current PCI options for lesions include atherectomy or and potentially intravascular if available approved at this The PCI strategy for lesions is still with a diagnostic and treatment suggested in The randomized trial may provide further guidance regarding the of atherectomy compared with Regardless of approach, and safe treatment of lesions requires with multiple techniques in to the of as well as expertise in and managing such as coronary and stent is a of the that between and 12 months stent and usually as While is less common in current due to the increasing use of and stent failure still at a rate of the first the treatment of remains an clinical for include treatment of a prior stent and total stent imaging is critical in assessing the mechanism of particularly treatment of lesions has been shown to rates of target lesion and vessel For lesions with from arterial and vessel prior to stent the first is to optimal of the stent by utilizing atherectomy with concurrent contrast and/or potentially intravascular the stent is additional treatment of the lesion on single multiple of the stent have been at the of the For treatment with a of is to other treatment are data for treating lesions multiple stent by intravascular is the preferred treatment available in the United to this patient especially the high rate of target lesion failure when of stent are at a single coronary In the coronary may be available in the and offer an to or for to lower rates of arterial left internal bypass interventions are performed in However, intervention a high risk for distal to and periprocedural This risk can be reduced by the use of devices and direct and the use of are the only devices available in the United but are likely due to technical with their use, limited and and procedural some data from observational prior randomized data that devices should be used in intervention I PCI outcomes intervention are poor for both and As a several recommend PCI of the coronary artery if including to high volume CTO PCI operators if In patients with due to strategy may be to initially the by staged coronary artery The artery by the may a complex CTO and require specialized CTO PCI techniques for revascularization. may also be PCI in bleeding risk lesions the of a significant and are in of lesions treated by have been proposed to coronary with the the and These lesions are more to than lesions due to in the at which the the main in vessel the potential need for a and an increase in both and long-term major adverse In multiple studies have shown that for disease limited to of the of the a can be to an PCI the main vessel and is of the main vessel stenosis, the main vessel is with a stent to proximal and a stent based on the distal this strategy at the to reduce the risk for The proximal of the proximal of the stent is then performed with a to improve proximal stent and facilitate of the if If angiography shows in myocardial infarction flow in the the procedure can be at the are if an is However, if flow in the is compromised despite a strategy can be such as the and or For lesions that require an strategy disease into the beyond from the or the of the is for a various techniques can be such as or other LM CAD is in of diagnostic coronary angiography cases, with of LM lesions at the distal In patients undergoing treatment of unprotected LM and multivessel CAD, and long-term major adverse cardiovascular events are between PCI and CABG, the SYNTAX score is However, PCI of LM lesions is associated with a higher revascularization especially with distal disease, as compared with Therefore, optimal PCI to lower the long-term risk of for LM disease is required when treating these lesions This includes routine intravascular imaging for complex LM or with lesion and utilization of the or other (Figure unprotected LM PCI is and should ideally be performed at a with on-site cardiac surgery. Furthermore, LM PCI outcomes are best when the procedure is performed by The ACC/AHA guidelines provide a for patients with ischemic heart disease, procedural risk, and a SYNTAX score and a for an SYNTAX Additionally, a heart team approach is to guide decision-making for elective unprotected LM The of coronary CTO lesions from to on the clinical presentation for coronary There is evidence that CTO PCI There is also data that CTO PCI in addition to optimal medical therapy can potentially improve LV function in patients with ischemic The on and the for PCI a recommendation for CTO PCI in the presence of There are several of CTO PCI should be angiography is required for lesion evaluation and to determine the appropriate lesion the main lesion strategies and need to be with strategies to achieve high success the lesion is vessel including intravascular imaging, should be to achieve optimal and long-term CTO PCI requires to the relevant should with CTO PCI to improve their and refer to CTO PCI centers when The optimal selection of the and duration of among patients with complex CAD undergoing PCI has been the of several In a of randomized trials comparing duration, that patients undergoing complex procedures as or more or lesions stent total stent or benefit from of than 12 months with increasing of complex In in the patients treated with months of 12 months of a similar of benefit they complex coronary at the time of on these patients with complex coronary anatomy may benefit from than months based on their lesion randomized data have shown that duration may be to be to with in patients complex PCI, which may be useful in patients with elevated bleeding regarding beyond 12 months be further by the profile of patients as assessed by risk scores such as the score or score than by the of the current data on the use of different for complex coronary particularly among those with CAD. However, the use of more antiplatelet the first or may be for those patients with particularly complex coronary anatomy and lower bleeding risk, particularly when with other ischemic risk such as ACS PCI can be safely performed without safety as in randomized clinical trials and observational with the potential for A SCAI approach and the appropriate patients and interventional procedures for has been for a include procedural success without clinical of coronary ischemia or access include to a of adverse an appropriate support with medical and planned It is to that procedures performed on patients with complex coronary anatomy or presentation for should be performed in a setting to an This for in of a periprocedural or adverse This is different from a patient who PCI in an where the preprocedural risk profile has to be the rate of cardiac surgery in routine PCI, this rate is increased in complex PCI procedures and when needed, the lack of on-site surgical availability have This that the majority of complex PCI procedures with a potential for higher complication rates or should be performed at with cardiac surgery (Figure Patients requiring PCI have complex in terms of coronary presenting physiology, and clinical Evidence to guide the treatment of complex CAD and percutaneous treatment approaches have the to this As we to determine the best treatment strategies for complex CAD, this SCAI consensus document an to offer guidance for excellent outcomes for complex PCI and to support of this growing patient to for to the writing of this also to and for their in some of the in this Disclosures of with The is not for the or of any supporting by the than should be to the for the