Commentary: The Management of ACS in Older Patients: Is Age Just a Number?

Disclosure: None
Pub Date: December 12, 2022
Author: Jennifer A. Rymer, MD, MBA, MHS and L. Kristin Newby, MD
Affiliation:

Over the past decade, there has been increasing evidence on how best to manage the geriatric population presenting with an acute coronary syndrome (ACS). The AHA scientific statement entitled, “Management of Acute Coronary Syndrome in the Older Adult Population” examines the body of evidence for management of older patients with ACS, focusing on the relevant issues of age-related mechanisms predisposing patients to ACS and the appropriate management strategies for the older ACS patient.

Perhaps one of the most difficult clinical decisions in older patients with ACS is whether to pursue an invasive management strategy. The current scientific statement highlights that decisions about invasive management can be complex and require an understanding of the patient’s goals, preferences, and baseline comorbidities and cognitive status. For patients presenting with NSTEMI, the After Eighty Study demonstrated that an invasive strategy for treating patients 80 years and older was associated with a decreased risk of recurrent MI and urgent revascularization but no significant difference in mortality, stroke or bleeding.¹ However, there was a trend toward harm for patients older than 90 years. Long-term follow-up of participants in the After Eighty Study demonstrated superiority of an invasive strategy over a conservative strategy for the composite endpoint (death, MI, urgent revascularization or stroke) but no significant mortality benefit.²

When using risk scores to aid in the decision about pursing an invasive strategy, it must be emphasized that both risk calculators commonly used to assess timing of revascularization for patients with ACS (i.e., the GRACE and TIMI risk scores) are heavily weighted for age, so that many older patients will be assessed as high risk with an indication for an early invasive strategy primarily because of age.^3-4 However, not all similarly aged patients have the same presenting clinical and cognitive status, and frailty is poorly captured in all of our current risk calculators. However, frailty is not necessarily prohibitive of a patient undergoing an invasive strategy. A recent analysis of patients > 75 years old presenting with an MI demonstrated that patients with frailty based on a claims-based frailty index had a significant benefit for undergoing PCI compared with patients who were medically managed.⁵ These risk scores also fail to capture the higher risk of bleeding in older patients that may offset some of the benefit on ischemic endpoints. However, appropriate dosing and adjustment for renal function as well as radial access should help to reduce bleeding risk.

For patients presenting with STEMI, the current statement highlights that primary PCI should be pursued, but that careful consideration should be given to older patients presenting with cardiogenic shock. Peripheral vascular disease, renal dysfunction, and higher bleeding risk are all associated with increasing age; therefore, the use of mechanical circulatory support and the requisite large bore access can place older patients at increased risk of adverse vascular and bleeding outcomes. As age is an independent risk factor associated with mortality in older patients presenting with cardiac arrest or cardiogenic shock,⁶ when possible, the statement emphasizes the need to carefully select the appropriate patient to undergo PCI in the setting of cardiogenic shock and cardiac arrest. However, if PCI is pursued in the setting of shock or cardiac arrest, there does not appear to be an age interaction with benefit for culprit-only vs. multivessel PCI, as shown in the recent CULPRIT-SHOCK trial.⁷

When an invasive strategy is employed, it is critical to consider strategies that reduce bleeding and vascular complications. When feasible, radial access should be utilized as both a bleeding avoidance strategy and to reduce vascular complications associated with femoral access. In older patients, the estimated glomerular filtration rate (eGFR) can be overestimated leading to mis-dosing various antithrombotic therapies. In particular, careful consideration should be given to use, and if used, dosing of glycoprotein IIA/IIIB inhibitors (GPI), such as eptifibatide, in the older population given renal clearance of these agents. Renal protection strategies before, during, and after PCI also should be carefully considered. Use of the contrast threshold (3x eGFR) can be particularly useful for reducing the risk of contrast-induced nephropathy.⁸ For antiplatelet therapy, the statement highlights that clopidogrel and ticagrelor are most commonly used in the older population, with avoidance of prasugrel inpatients >75 years except in rare cases of patients with high ischemic risk (i.e., concomitant diabetes, complex anatomy or intolerance of the other P2Y12 inhibitors). Guidance is given to avoid loading with a P2Y12 inhibitor upstream of knowing the patient’s anatomy, particularly among patients undergoing an early invasive strategy. However, this is an ongoing area of general clinical uncertainty that warrants additional exploration to confirm the balance of thrombotic risk vs potential benefits of waiting to start a P2Y12 agent. As many older patients are classified as high-bleeding risk (HBR), strategies to shorten dual antiplatelet therapy (DAPT) safely after an ACS event are critical in mitigating bleeding risk. Shortening of DAPT requires a careful assessment of and thoughtful discussion between the clinician and patient regarding the ischemic vs. bleeding risks.

Among older patients with severe multivessel or left main disease, the statement emphasizes that coronary artery bypass grafting (CABG) has a survival benefit, but that for the decision to pursue CABG it is critical to employ both a Heart Team approach as well as patient-centered assessments that consider post-surgical rehabilitation, nutritional status, cognitive status and overall frailty. The statement underscores that the STS PROM score assesses the risk of early mortality after CABG in all ages; however, a patient-centered approach that carefully discusses the risks and benefits, and incorporates caregivers, is necessary to maximize the likelihood of an optimal outcome. The authors importantly emphasize that for cases in which clinical futility is a concern, a multidisciplinary approach should be utilized and include multiple stakeholders, including the patient, involved caregivers and family, the Heart Team, nursing, physical or occupational therapy and nutrition. The involvement of these stakeholders is needed to ensure that goals of care are adequately addressed and if revascularization is not chosen, appropriate transitions of care to the outpatient setting can occur.

The rapid growth in the population over 75 years of age raises the imperative to summarize newer evidence and outline best practices in management of older adults with ACS. To that end, the current scientific statement addresses important considerations in the pathophysiology of ACS in the elderly, risk assessment, pharmacologic and invasive management, and the role of comorbidities and preferences in decision-making in older ACS patients. In doing so, the statement highlights what is known and provides guidance for managing this important group of ACS patients. At the same time, it raises awareness us of gaps in our knowledge about treatment of ACS in older adults that will require additional investigation to ensure optimal treatment of this complex population. As this population is complex without a one-size-fits-all strategy, it is important to involve diverse stakeholders to develop a patient-centric plan for older patients.