DAPT complications — viva

Stem

Practice viva. The examiner works through four scenarios in the year after PCI: the default duration and high bleeding risk, a request to switch drug, atrial fibrillation needing anticoagulation, and an operation.^[1]

Branch A — The default and who is HBR

Examiner: A man has had PCI for an NSTEMI. How long does he need DAPT, and what changes that?^[1][2]

Strong answer:

• ESC 2023: a P2Y12 receptor inhibitor in addition to aspirin is recommended 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 with aspirin and an oral P2Y12 inhibitor should be administered for at least 1 year to reduce MACE (COR 1, LOE A).^[2]
• ESC 2023 says that in specific clinical scenarios the default can be shortened, extended or modified (switching, de-escalation), and that abbreviation and de-escalation strategies should only be used as alternatives to 12-month DAPT, in general driven by a motivation to reduce bleeding, for example if the patient is HBR.^[1]

Follow-up: How do you decide he is HBR?^[1][2]

• ESC 2023 says HBR should be assessed in a structured manner, for example a single major or two minor ARC-HBR characteristics; in its Figure 12 legend (ACS with an indication for oral anticoagulation) it also regards a PRECISE-DAPT score of 25 or more as HBR.^[1]
• ACC/AHA 2025 Table 22 prints the criteria; at least 1 major or 2 minor criteria helps to identify those at increased risk of bleeding.^[2]
• Major criteria include anticipated long-term oral anticoagulation, eGFR under 30 mL/min, haemoglobin under 11 g/dL, moderate or severe baseline thrombocytopenia (platelet count under 100 × 10⁹/L) and active malignancy (excluding non-melanoma skin cancer) within the past 12 months; age 75 years or more and moderate CKD are minor criteria.^[2]

Branch B — A request to change drug

Examiner: Six weeks after a STEMI treated with primary PCI, a patient on aspirin and ticagrelor has breathlessness on ticagrelor that he cannot tolerate and asks to change drug; prasugrel is not available to him. What do you say?^[2][1]

Strong answer:

• ACC/AHA 2025 says ticagrelor may cause subjective transient dyspnoea in approximately 10% to 15% of patients after ACS.^[2]
• ESC 2023 lists non-bleeding side effects such as dyspnoea on ticagrelor among the reasons to switch, and says switching between oral P2Y12 receptor inhibitors may be considered in selected cases.^[1]
• ESC 2023 Recommendation Table 5 recommends clopidogrel (300–600 mg loading dose, 75 mg once daily maintenance) when prasugrel or ticagrelor are not available, cannot be tolerated, or are contraindicated (Class I, Level C); here ticagrelor cannot be tolerated and prasugrel is not available.^[1]
• ESC 2023 describes switching from prasugrel or ticagrelor to clopidogrel as de-escalation, and its Recommendation Table 6 says de-escalation of antiplatelet therapy in the first 30 days after an ACS event is not recommended (Class III, Level B); at six weeks he is beyond those 30 days.^[1]
• ESC 2023 also notes a potential risk of increased ischaemic events with de-escalation.^[1]

Follow-up: In another patient after ACS and PCI who tolerates ticagrelor, when may de-escalation be used to reduce bleeding risk?^[1][2]

• ESC 2023: de-escalation of P2Y12 receptor inhibitor treatment, for example a switch from prasugrel or ticagrelor to clopidogrel, may be considered as an alternative DAPT strategy to reduce bleeding risk (Class IIb, Level A); its text says de-escalation may be considered as an alternative strategy beyond 30 days after an ACS, in order to reduce the risk of bleeding events.^[1]
• ACC/AHA 2025: in patients with ACS undergoing PCI, de-escalation after 1 month may be reasonable to reduce bleeding risk (COR 2b, LOE B-R).^[2]
• ESC 2023 reports TALOS-AMI, an investigator-initiated, open-label, multicentre, non-inferiority, randomised trial: unguided de-escalation from ticagrelor to clopidogrel after 1 month of DAPT with ticagrelor and aspirin, in 2697 ACS patients (46% NSTEMI or unstable angina, 54% STEMI), led to significant 12-month reductions in net adverse clinical events and bleeding events; ESC 2023 notes that the trial only included East Asian populations.^[1]

Branch C — Atrial fibrillation and PCI

Examiner: A 71-year-old man with known atrial fibrillation (CHA2DS2-VASc score 3) on apixaban has an NSTEMI and an uncomplicated PCI. How do you combine the drugs?^[1]

Strong answer:

• ESC 2023: for AF with a CHA2DS2-VASc score of 1 or more in men and 2 or more in women, after up to 1 week of triple therapy following the ACS event, a NOAC at the stroke-prevention dose with a single antiplatelet agent (preferably clopidogrel) for up to 12 months is recommended as the default (Class I, Level A).^[1]
• ESC 2024 AF, which is newer than ESC 2023 ACS, recommends early cessation (1 week or less) of aspirin and continuation of an OAC (preferably a DOAC) with a P2Y12 inhibitor (preferably clopidogrel) for up to 12 months in AF patients with ACS undergoing an uncomplicated PCI, to avoid major bleeding, if the risk of thrombosis is low or bleeding risk is high (Class I, Level A). Triple therapy with aspirin, clopidogrel and an OAC for longer than 1 week after an ACS should be considered in patients with AF when ischaemic risk outweighs bleeding risk, with the total duration (1 month or less) decided by assessing these risks and clearly documenting the discharge plan (Class IIa, Level C).^[5][1]
• Ticagrelor or prasugrel as part of triple antithrombotic therapy is not recommended (ESC 2023, Class III, Level C); ACC/AHA 2025 generally favours clopidogrel because the potent-agent trials excluded patients requiring long-term anticoagulation.^[1][2]
• Discontinuation of antiplatelet treatment in patients treated with an OAC is recommended after 12 months (ESC 2023, Class I, Level B).^[1]

Follow-up: What evidence supports dropping aspirin?^[1]

• ESC 2023 reports a meta-analysis of four NOAC-based RCTs in 10 234 AF patients undergoing PCI: dual therapy lowered major or clinically relevant non-major bleeding against triple therapy (RR 0.66).^[1]
• The trade-off was a borderline increase in MI and a significant increase in stent thrombosis, with an absolute 2.3% fall in major bleeding against an absolute 0.4% rise in stent thrombosis, and no effect on overall MACE.^[1]

Branch D — An operation after PCI

Examiner: Five months after an elective PCI, a patient on aspirin and clopidogrel needs a time-sensitive operation. What do you recommend?^[7]

Strong answer:

• ESC 2022: after elective PCI, it is recommended to delay time-sensitive non-cardiac surgery until a minimum of 1 month of DAPT has been given (Class I, Level B); elective surgery is recommended to wait until 6 months after elective PCI and 12 months after an ACS (Class I, Level A).^[7]
• With a recent PCI, it is recommended that management of antiplatelet therapy is discussed between the surgeon, anaesthesiologist and cardiologist (Class I, Level C).^[7]
• If P2Y12 interruption is indicated, it is recommended to withhold clopidogrel for 5 days (ticagrelor 3–5 days, prasugrel 7 days) (Class I, Level B), and to continue aspirin peri-operatively after previous PCI if the bleeding risk allows (Class I, Level B).^[7]
• If antiplatelet therapy was interrupted, restarting it as soon as possible (within 48 h) after surgery, according to interdisciplinary risk assessment, is recommended (Class I, Level C).^[7]

Follow-up: What if the patient bleeds heavily in theatre?^[7]

• ESC 2022: for patients on antiplatelet therapy with excessive or life-threatening peri-operative bleeding, platelet transfusion is recommended as a bail-out strategy.^[7]
• Ticagrelor and its active metabolite may also inhibit aggregation of transfused platelets (ESC 2022).^[7]