Patient Selection and Appropriate Use Criteria

Abstract

The American College of Cardiology, Society for Cardiovascular Angiography and Interventions, Society of Thoracic Surgeons, and American Association for Thoracic Surgery, and other societies, developed and published appropriate use criteria (AUC) for coronary revascularization initially in 2009 [1, 2]. The AUC were updated in 2012, and more recently in 2017. The primary purpose of the AUC is to provide a framework to assess clinical practice patterns, expand physician decision-making, and improve the quality of care [1]. Since the publication of the AUC for coronary revascularization in 2009, the volume of nonacute PCI has significantly decreased [3, 4]. Moreover, the proportion of nonacute PCI’s classified as inappropriate has also declined [3].

Introduction

The American College of Cardiology, Society for Cardiovascular Angiography and Interventions, Society of Thoracic Surgeons, and American Association for Thoracic Surgery, and other societies, developed and published appropriate use criteria (AUC) for coronary revascularization initially in 2009 [1, 2]. The AUC were updated in 2012, and more recently in 2017. The primary purpose of the AUC is to provide a framework to assess clinical practice patterns, expand physician decision-making, and improve the quality of care [1]. Since the publication of the AUC for coronary revascularization in 2009, the volume of nonacute PCI has significantly decreased [3, 4]. Moreover, the proportion of nonacute PCIs classified as inappropriate has also declined [3].

AUC are either evidence-based or are expert consensus opinion (when evidence is lacking), and are approved by ACC and the American Heart Association (AHA). AUC are not intended to diminish the complexity or uncertainty of clinical decision-making, and are not to replace thoughtful clinical judgment [1].

Appropriate Use Criteria for Stable Ischemic Heart Disease

The AUC guidelines assume patients are receiving all indicated therapies for secondary prevention of cardiovascular disease with pharmacotherapy at doses that adequately control patients’ symptoms or are maximally tolerated [1]. AUC does not evaluate all patient conditions/variables which may affect the strategies used to manage patients with CAD. Examples of such conditions/variables include [1]:

• Severe chronic kidney disease.

• Severe peripheral vascular disease.

• Known malignancies.

• Poor lung function.

• Advanced liver disease.

• Advanced dementia.

• Other comorbidities that have excluded patients from clinical trials that provide the evidence base for coronary revascularization.

In developing these AUC for coronary revascularization in patients with stable ischemic heart disease (SIHD), a panel of experts scored each indication using the following definition of appropriate use: A coronary revascularization is appropriate care when the potential benefits, in terms of survival or health outcomes (symptoms, functional status, and/or quality of life), exceed the potential negative consequences of the treatment strategy. The panel scored each indication on a scale from one to nine based on their level of agreement with the definition of appropriate use for that indication as follows [1]:

• Score 1 to 3: Rarely appropriate care (risks > benefit).

• Score 4 to 6: May be appropriate care (potential benefit).

• Score 7 to 9: Appropriate care (risk < benefit).

In patients with SIHD, AUC indications for coronary revascularization were developed considering several variables [1]:

• Clinical presentation/ischemic symptoms.

• Use of antianginal medications (Beta-blockers, Calcium channel blockers, Long-acting nitrates, Ranolazine).

• Results of noninvasive tests to evaluate the presence and severity of myocardial ischemia (Table 6.1).

• Presence of other confounding factors and comorbidities such as diabetes.

• Extent and complexity of anatomic coronary artery disease.

• Prior coronary artery bypass surgery.

• Invasive testing such as intravascular ultrasound (IVUS) and invasive physiology such as fractional flow reserve (FFR).

Table 6.1 Noninvasive risk stratification

Per AUC, significant coronary stenosis in SIHD was defined as [1]:

• ≥70% luminal diameter narrowing of epicardial stenosis, measured by visual assessment in the “worst view” angiographic projection.

• ≥50% luminal diameter narrowing of left main stenosis, measured by visual assessment in the “worst view” angiographic projection.

• 40% to 70% luminal narrowing of epicardial stenosis, measured by visual assessment in the “worst view” angiographic projection with an abnormal FFR (abnormal if ≤0.80).

Refer to Figs. 6.1, 6.2, and 6.3 for a summary of AUC for SIHD.

Fig. 6.1

(a) AUC for one vessel disease. (b) AUC for two-vessel disease. (c) AUC for three-vessel disease. (d) AUC for left main coronary artery stenosis. (Adapted from Patel et al. [1] with permission from Springer Nature). The number in parentheses next to the rating reflects the median score for that indication. *Substitution of a newer coronary pressure ratio that does not require hyperemia for FFR may be considered provided the appropriate reference values are used. A = appropriate; AA = antianginal; BB = beta-blockers; CABG = coronary artery bypass graft; FFR = fractional flow reserve; LAD = left anterior descending coronary artery; LCX = left circumflex artery; LMCA = left main coronary artery; M = may be appropriate; PCI = percutaneous coronary intervention; R = rarely appropriate; and SYNTAX = Synergy between PCI with Taxus and Cardiac Surgery trial)

Fig. 6.2

(a) AUC for an internal mammary artery to left anterior descending artery patent and without significant stenosis. (b) AUC for an internal mammary artery to the left anterior descending artery, not patent. (Adapted from Patel et al. [1] with permission from Springer Nature). The number in parentheses next to the rating reflects the median score for that indication. *Substitution of a newer coronary pressure ratio that does not require hyperemia for FFR may be considered provided the appropriate reference values are used. A = appropriate; AA = Antianginal; BB = beta-blockers; CABG = coronary artery bypass graft; FFR = fractional flow reserve; IMA = internal mammary artery; LAD = left anterior descending coronary artery; M = may be appropriate; PCI = percutaneous coronary intervention; and R = rarely appropriate)

Fig. 6.3

AUC for stable ischemic heart disease undergoing procedures for which coronary revascularization may be considered. (Adapted from Patel et al. [1] with permission from Springer Nature). The number in parentheses next to the rating reflects the median score for that indication. A = appropriate; AA = Antianginal; BB = beta-blockers; CABG = coronary artery bypass graft; CAD = coronary artery disease; LAD = left anterior descending coronary artery; M = may be appropriate; PCI = percutaneous coronary intervention; R = rarely appropriate; SYNTAX = Synergy between PCI with Taxus and Cardiac Surgery trial; and TAVR = transcatheter aortic valve replacement)

Appropriate Use Criteria for Acute Coronary Syndrome

In developing these AUC for coronary revascularization in patients with acute coronary syndrome (ACS), a panel of experts scored each indication using the following definition of appropriate use: A coronary revascularization or antianginal therapeutic strategy is appropriate care when the potential benefits, in terms of survival or health outcomes (symptoms, functional status, and/or quality of life) exceed the potential negative consequences of the treatment strategy. The panel scored each indication on a scale from one to nine based on their level of agreement with the definition of appropriate use for that indication as follows [2]:

• Score 1 to 3: Rarely appropriate care (risks > benefit).

• Score 4 to 6: May be appropriate care (potential benefit).

• Score 7 to 9: Appropriate care (risk < benefit).

In patients with ACS, AUC indications for coronary revascularization were developed considering several variables [2]:

• Clinical presentation (STEMI, NSTEMI, or other ACS).

• Time from onset of symptoms.

• Presence of other complicating factors (severe heart failure or cardiogenic shock, hemodynamic or electrical instability, presence of left ventricular dysfunction, persistent or recurring ischemic symptoms).

• Prior treatment with fibrinolytics.

• Predicted risk as estimated by the Thrombolysis In Myocardial infarction score.

• Relevant comorbidities.

• Extent of anatomic disease in the culprit and non-culprit arteries.

Determining the significance of coronary stenosis in ACS includes not only the percent luminal diameter narrowing but also the angiographic appearance of the stenosis and distal flow pattern. Per AUC, coronary stenosis in ACS was defined as follows [2]:

• Severe:

  • ≥70% luminal diameter narrowing of epicardial stenosis, measured by visual assessment in the “worst view” angiographic projection.

  • ≥50% luminal diameter narrowing of the left main artery, measured by visual assessment in the “worst view” angiographic projection.

• Intermediate:

  • ≥50% and <70% diameter narrowing of epicardial stenosis, measured by visual assessment in the “worst view” angiographic projection.

Refer to Fig. 6.4 for a summary of AUC for ACS.

Fig. 6.4

(a) AUC for STEMI immediate revascularization by PCI. (b) AUC for STEMI initial treatment by fibrinolytic therapy. (c) AUC for STEMI revascularization of the non-culprit artery (D) AUC for NSTEMI/Unstable angina. (Adapted from Patel et al. [2] with permission from Springer Nature). The number in parenthesis next to the rating reflects the median score for that indication. A = appropriate; CABG = coronary artery bypass graft; FFR = fractional flow reserve; HF = heart failure; M = may be appropriate; NSTEMI = non–ST-segment elevation myocardial infarction; PCI = percutaneous coronary intervention; R = rarely appropriate; STEMI = ST-segment elevation myocardial infarction; TIMI = Thrombolysis In Myocardial Infarction)

Pearls

• More than one treatment may be considered “Appropriate,” “May Be Appropriate,” or “Rarely Appropriate” for any clinical indication and a shared decision approach should be undertaken to determine which treatment is suitable.

• Rating of “appropriate care” does not mandate that a revascularization procedure be performed; similarly, a rating of “rarely appropriate care” should not prevent a revascularization procedure from being performed.

• If a clinician decides not to follow the AUC rating, the provider should document case-specific details that are not accounted for, and the rationale for choosing an alternative treatment plan.

• AUC only covers clinical scenarios where the culprit artery and additional non-culprit arteries are treated at the time of primary PCI, or later during the initial hospitalization.

• Consider a heart team evaluation when faced with complex clinical scenarios or patients with severe CAD.