Secondary prevention after acute coronary syndrome — structured viva

Abbreviations

Stem

Practice viva. You are the cardiology registrar. The examiner works through the discharge plan after an acute coronary syndrome: antiplatelet duration and alternatives, lipid lowering, beta-blockers, cardiac rehabilitation, colchicine and vaccination, and Australian differences. Name the body, year and strength for every recommendation.

Branch A — Antiplatelet duration

Examiner: What is the default antiplatelet regimen after ACS, and when can you shorten it?

Strong answer:

• ESC 2023 recommends a P2Y12 receptor inhibitor in addition to aspirin in all ACS patients for 12 months unless there is HBR (Class I, Level A).^[1]
• ACC/AHA 2025: in patients with ACS who are not at high bleeding risk, DAPT should be given for at least 1 year to reduce MACE (COR 1, LOE A).^[2]
• ESC 2023 says shortened and de-escalated strategies should only be used as alternatives, in general driven by a motivation to reduce bleeding risk.^[1]
• ESC 2023: in patients event-free after 3–6 months of DAPT and not at high ischaemic risk, SAPT (preferably a P2Y12 receptor inhibitor) should be considered (Class IIa, Level A); in HBR patients, monotherapy after 1 month may be considered (Class IIb, Level B).^[1]
• ACC/AHA 2025: after tolerated ticagrelor-based DAPT, transition to ticagrelor monotherapy 1 month or more after PCI is useful to reduce bleeding risk (COR 1, LOE A).^[2]

Follow-up: Can you de-escalate to clopidogrel at 2 weeks?^[1]

• No: ESC 2023 says de-escalation of antiplatelet therapy in the first 30 days after an ACS event is not recommended (Class III, Level B), because of a potential risk of increased ischaemic events.^[1]
• ACC/AHA 2025 places de-escalation after 1 month: in patients with ACS undergoing PCI, switching from ticagrelor or prasugrel to clopidogrel after 1 month may be reasonable to reduce bleeding risk (COR 2b, LOE B-R).^[2]

Branch B — Lipids

Examiner: Walk me through LDL-C lowering after ACS.

Strong answer:

• ESC 2023 recommends that high-dose statin is initiated or continued as early as possible, regardless of initial LDL-C (Class I, Level A), and recommends aiming for LDL-C below 1.4 mmol/L with a reduction of 50% or more (Class I, Level A).^[1]
• ESC 2023: if the goal is not achieved despite maximally tolerated statin after 4–6 weeks, adding ezetimibe is recommended (Class I, Level B); if not achieved despite maximally tolerated statin and ezetimibe after 4–6 weeks, adding a PCSK9 inhibitor is recommended (Class I, Level A).^[1]
• ESC/EAS 2025: initiating combination therapy with high-intensity statin plus ezetimibe during index hospitalisation for ACS should be considered in treatment-naïve patients not expected to achieve the LDL-C goal with statin therapy alone (Class IIa, Level B).^[3]
• ACC/AHA 2025 uses thresholds on maximally tolerated statin: adding a non-statin is recommended at LDL-C 70 mg/dL or more to further reduce the risk of MACE (COR 1, LOE A) and is reasonable at 55 to 69 mg/dL to reduce the risk of MACE (COR 2a, LOE B-R).^[2]

Follow-up: When do you recheck lipids?^[1][2]

• ESC 2023 says lipid levels should be re-evaluated 4–6 weeks after each treatment or dose adjustment; ACC/AHA 2025 recommends a fasting lipid panel 4 to 8 weeks after initiation or dose adjustment of lipid-lowering therapy to assess response or adherence (COR 1, LOE C-LD).^[1][2]

Branch C — Beta-blockers

Examiner: Should every patient go home on a beta-blocker?

Strong answer:

• ESC 2023 recommends beta-blockers in ACS patients with LVEF 40% or less regardless of HF symptoms (Class I, Level A) and says routine beta-blockers for all ACS patients regardless of LVEF should be considered (Class IIa, Level B).^[1]
• NHFA/CSANZ 2025 says to consider withholding beta-blockers in people with ACS and preserved LV systolic function who have undergone coronary revascularisation and are receiving optimal medical therapy (weak recommendation, moderate certainty).^[5]
• Open-label trials that ESC 2023 listed as ongoing have since reported, with different end points and results: in REDUCE-AMI (early coronary angiography, LVEF 50% or more) long-term beta-blocker treatment did not lead to a lower risk of the primary end point than no beta-blocker use; in REBOOT (discharged after invasive care, LVEF above 40%) beta-blocker therapy appeared to have no effect on its primary outcome; whereas in BETAMI-DANBLOCK (LVEF at least 40%) beta-blocker therapy led to a lower risk of death or MACE than no beta-blocker therapy (hazard ratio 0.85).^{[1][7][9][10][4]}

Follow-up: What about stopping a beta-blocker years after an MI?^[8]

• In the open-label, non-inferiority AβYSS trial (history of MI, LVEF at least 40%, no cardiovascular event in the previous 6 months), interruption of long-term beta-blocker treatment was not found to be non-inferior to continuation, and did not seem to improve quality of life.^[8][1]

Branch D — Cardiac rehabilitation and lifestyle

Examiner: What do you tell the patient about cardiac rehabilitation?

Strong answer:

• ESC 2023 recommends that all ACS patients participate in a medically supervised, structured, comprehensive, multidisciplinary exercise-based cardiac rehabilitation and prevention programme (Class I, Level A).^[1]
• ESC 2026: CR after ACS or with chronic coronary syndromes is recommended to reduce the risk of cardiovascular mortality and MI (Class I, Level A); after ACS, CR should ideally begin in the first 14 days and no later than 30 days.^[4]
• ACC/AHA 2025: patients with ACS should be referred to an outpatient CR program before hospital discharge to reduce death, MI and hospital readmissions and to improve functional status and quality of life (COR 1, LOE A); a home-based program is a reasonable alternative to a centre-based one to improve functional status and quality of life (COR 2a, LOE B-R).^[2]
• ESC 2023 recommends that ACS patients adopt a healthy lifestyle, including stopping all smoking of tobacco, a healthy (Mediterranean-style) diet, alcohol restriction, regular aerobic physical activity and resistance exercise, and reduced sedentary time (Class I, Level B).^[1]

Branch E — Colchicine and vaccination

Examiner: Would you add colchicine, and what about vaccines?

Strong answer:

• ESC 2023: low-dose colchicine (0.5 mg once daily) may be considered, particularly if other risk factors are insufficiently controlled or if recurrent cardiovascular events occur under optimal therapy (Class IIb, Level A); ACC/AHA 2025: low-dose colchicine may be reasonable after ACS to reduce MACE (COR 2b, LOE B-R).^[1][2]
• In COLCOT (recruited within 30 days after MI), colchicine 0.5 mg once daily led to a significantly lower risk of the primary end point than placebo (hazard ratio 0.77; P = 0.02); in CLEAR (colchicine started soon after MI and continued for a median of 3 years) the primary outcome was not reduced (hazard ratio 0.99; P = 0.93).^[13][12]
• Influenza vaccination is recommended for all ACS patients (ESC 2023, Class I, Level A), and annual influenza vaccination is recommended for patients with ACS without a contraindication to reduce the risk of death and MACE (ACC/AHA 2025, COR 1, LOE A).^[1][2]

Branch F — Australian practice

Examiner: How does the 2025 Australian guideline differ?

Strong answer:

• In people discharged following an ACS: DAPT for 6–12 months at high ischaemic and/or low bleeding risk (strong, high); cease DAPT at 1–3 months and continue SAPT at low ischaemic and/or high bleeding risk (strong, high).^[5]
• After a completed course of DAPT (1–12 months), a long-term P2Y12 inhibitor over aspirin (strong, moderate); the NHFA/CSANZ 2025 Figure 6 legend notes that current Pharmaceutical Benefits Scheme criteria preclude the prescription of ticagrelor as single therapy.^[5]
• Use of an angiotensin receptor–neprilysin inhibitor in people with ACS is not recommended (strong, high).^[5]
• Vaccinations for influenza and other respiratory pathogens are recommended (consensus).^[5]