HK-MLE 50 MCQs: Ischaemic Heart Disease + Heart Failure

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PART A — ISCHAEMIC HEART DISEASE (Q1–25)

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• A) Invasive coronary angiography is reserved for patients with high pre-test probability, positive non-invasive stress tests, or those proceeding to revascularisation — not a first-line investigation in intermediate-risk stable angina.
• B) Resting echocardiography assesses wall motion and function at rest but does not evaluate ischaemia; it would not demonstrate the stress-induced ischaemia causing his symptoms.
• D) Stress cardiac MRI is an excellent option for ischaemia detection but is a second-line modality after CTCA for initial anatomical assessment in most guidelines.
• E) A Holter monitor assesses arrhythmias and is not indicated for exertional chest pain with typical anginal features.

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• A) Clopidogrel reduces thrombotic events but has no anti-anginal effect; it is added for secondary prevention in ACS or PCI, not for symptom control in stable angina.
• B) Long-acting nitrates are a valid third anti-anginal agent but have significant tolerance issues and nitrate-free interval requirements; ranolazine is preferred when a CCB and beta-blocker are already on board.
• C) Diltiazem is a non-dihydropyridine CCB that lowers heart rate like atenolol — combining two rate-limiting agents risks bradycardia and heart block and is generally contraindicated.
• E) Ivabradine reduces heart rate via If channel inhibition and is an option only when the patient is in sinus rhythm and beta-blockers are contraindicated; it should not be added to a beta-blocker without careful monitoring.

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• A) Medical therapy alone for CCS III symptoms with angiographically significant disease and viable myocardium is inferior to revascularisation for symptom relief and prognosis.
• B) Culprit-only PCI does not address the haemodynamically significant RCA disease and leaves residual ischaemia, which is a major predictor of adverse outcomes.
• C) PCI to both vessels is a valid option in non-diabetic patients with low SYNTAX score, but in a diabetic patient, CABG is definitively preferred due to more complete revascularisation and better outcomes.
• E) FFR-guided PCI is a sound approach for assessing intermediate lesions, but in a diabetic patient with significant multivessel disease, CABG remains the preferred strategy over any form of PCI.

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• A) Morphine is a HKMLE trap — while it relieves pain, morphine delays absorption of oral P2Y12 inhibitors via gastroparesis and has been associated with worse outcomes in ACS (CRUSADE registry data); it should be used sparingly if at all.
• C) Heparin (UFH) is given as an adjunct, typically as a weight-based bolus (70–100 IU/kg) at the time of PCI rather than a flat 5000-unit dose before — antiplatelet therapy takes priority.
• D) GTN relieves pain but does not alter the natural history of STEMI or reduce infarct size; it is contraindicated if the patient has taken a PDE5 inhibitor within 24–48 hours and if inferior MI is associated with right ventricular infarct.
• E) IV beta-blockers are contraindicated in the acute phase when there is heart failure, low BP, or HR < 60; oral beta-blockers started within 24 hours are appropriate but IV is not routine pre-PCI.

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• A) LV cardiogenic shock presents with hypotension but with pulmonary oedema (crackles, elevated PCWP) due to LV failure — clear lung fields argue against this.
• C) Acute mitral regurgitation from papillary muscle rupture causes severe pulmonary oedema with a new holosystolic murmur — lung fields would not be clear.
• D) Tension pneumothorax causes absent breath sounds, tracheal deviation, and raised JVP — it would not be a complication in the acute MI context without a procedure, and the ECG context confirms MI.
• E) Dressler syndrome (post-MI pericarditis) occurs weeks after MI, not acutely, and presents with fever, pleuritic chest pain, and pericardial/pleural effusion.

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• A) Papillary muscle rupture also causes a pansystolic murmur but it is loudest at the apex and radiates to the axilla (mitral regurgitation pattern); it typically involves the posteromedial papillary muscle after inferior MI rather than anterior MI.
• C) LV free wall rupture causes acute tamponade (Beck's triad: hypotension, muffled heart sounds, raised JVP) without a murmur — not consistent with the murmur and thrill described.
• D) Acute aortic dissection presents with tearing interscapular pain and pulse differentials, not as a complication days after MI.
• E) Pulmonary embolism causes right heart strain, pleuritic pain, and hypoxia but not a loud pansystolic murmur with thrill in this clinical context.

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• B) Within 24 hours is appropriate for high-risk NSTE-ACS (TIMI ≥ 3 or GRACE > 140) without the specific very-high-risk ECG features like aVR elevation suggesting left main disease.
• C) Within 72 hours is the threshold for intermediate-risk patients (GRACE 109–140); this patient's TIMI 5 and ECG changes require earlier intervention.
• D) Conservative, ischaemia-driven strategy is reserved for low-risk patients (TIMI 0–1, no troponin rise, no significant ECG changes) and would be inappropriate here given objective high-risk features.
• E) Stress testing should not be performed during active ACS with positive biomarkers; it is reserved for stable, low-risk presentations after the acute phase.

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• A) Routine immediate angiography in all post-ROSC patients without STEMI is NOT supported by evidence — TOMAHAWK (2021) showed no mortality benefit and possible harm; this is the intended trap answer.
• B) TTM (now called targeted temperature management, targeting 32–36°C) is no longer mandatory in all comatose survivors — TTT-2 trial showed 33°C vs. 37.5°C had similar outcomes; TTM does not supersede angiography timing decisions.
• C) Waiting only for ST elevation misses patients with high clinical probability of coronary occlusion (e.g., known CAD, pre-arrest chest pain, shockable rhythm) who may benefit from early angiography.
• E) Emergency CABG is not a primary response to post-cardiac arrest management without first defining anatomy.

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• B) Waiting for troponin introduces dangerous delay in a potentially time-critical reperfusion scenario; troponin may be normal in the first 1–2 hours and should not delay cath lab activation.
• C) Echocardiography may support the diagnosis by showing regional wall motion abnormality but delays definitive therapy; it is not recommended as the primary decision-making tool when STEMI equivalent is suspected.
• D) Thrombolysis should only be given if primary PCI is not achievable within 120 minutes; in a system with PCI capability, cath lab activation is preferred over thrombolysis.
• E) Serial ECG observation is appropriate for non-ST-elevation ACS but not when new LBBB is present with acute chest pain — this would constitute unacceptable delay.

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• A) Repeat angiography is not indicated for Dressler syndrome, which is a pericardial — not coronary — complication; the clinical picture does not suggest recurrent MI.
• C) Antibiotics are used for bacterial (purulent) pericarditis; Dressler syndrome is autoimmune/inflammatory, not infectious, and antibiotics would be ineffective.
• D) Pericardiocentesis is reserved for cardiac tamponade with haemodynamic compromise; a friction rub without tamponade physiology does not require pericardiocentesis.
• E) Beta-blockers do not treat pericarditis and increasing the dose would address neither the fever nor the inflammatory pericardial process.

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• A) Adenosine terminates AV-nodal-dependent SVT (AVRT, AVNRT) but has no effect on VT and may precipitate haemodynamic deterioration; using adenosine in VT is a dangerous error.
• B) Carotid sinus massage can terminate vagally-sensitive SVT but has no role in VT and should not be performed in the context of acute MI due to carotid atherosclerosis risk.
• D) IV amiodarone 300 mg is the drug of choice for pulseless VT (in VF/VT arrest algorithms) and as adjunct post-cardioversion, but synchronised cardioversion is the primary treatment for haemodynamically tolerated VT in acute MI.
• E) Lidocaine is a second-line option for VT; historically used in acute MI but now supplanted by amiodarone; it is not the first-line choice per current guidelines.

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• A) Discharging a patient with hyperacute T waves in the context of chest pain risks missing an evolving STEMI — this is a high-stakes error and a known HKMLE trap.
• C) Early repolarisation shows concave ST elevation with a "fish-hook" pattern, not tall broad-based T waves in the anterior leads in the context of chest pain.
• D) Pericarditis shows saddle-shaped diffuse ST elevation with PR depression — isolated anterior hyperacute T waves in chest pain are not the hallmark of pericarditis.
• E) Posterior STEMI shows ST depression and tall R waves in V1–V3 (reciprocal changes); posterior leads (V7–V9) are useful for posterior MI, but this ECG pattern in V2–V5 is anterior, not posterior.

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• A) Dressler syndrome is an acute post-MI pericarditis occurring weeks after MI, not a chronic echocardiographic finding 6 months later.
• C) While the patient has dyspnoea, the specific echo finding of a dyskinetic apical segment indicates LV aneurysm as the underlying structural cause — "acute HF" is not a specific enough diagnosis.
• D) Papillary muscle dysfunction causes mitral regurgitation with a regurgitant jet on colour Doppler; the echo here describes an apical dyskinetic bulge, not valvular pathology.
• E) VSD presents acutely with a new murmur and step-up in RV oxygen saturation; it does not present as a dyskinetic segment 6 months post-MI.

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• A) 1 month DAPT followed by aspirin alone is appropriate for high-bleeding-risk patients (per ARC-HBR criteria) but not the default recommendation for all ACS-PCI patients.
• B) 3-month DAPT with P2Y12 continuation (aspirin withdrawal, so-called "P2Y12 monotherapy") is an emerging strategy for high bleeding risk, not a standard for all ACS-DES patients.
• D) 12 months was the historic standard from CURE trial era; 2023 ESC guidelines have moved toward risk-stratified duration with 6 months as the new default.
• E) Lifelong DAPT is not recommended and significantly increases major bleeding risk without proportionate ischaemic benefit beyond the first year.

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• A) Re-thrombolysis (repeat lytic administration) is contraindicated after failed first-line thrombolysis — it dramatically increases intracranial haemorrhage risk with no proven benefit.
• C) Pharmacoinvasive transfer within 3–24 hours is appropriate for successful thrombolysis (> 50% ST resolution) — not for failed thrombolysis where rescue PCI must be immediate.
• D) Conservative management with heparin alone in failed thrombolysis is associated with a very high infarct-related artery occlusion rate and excess mortality.
• E) GPIIb/IIIa inhibitors are adjuncts in selected PCI settings but do not replace mechanical reperfusion in failed thrombolysis.

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• A) IABP first then PCI inverts the priority; revascularisation is the life-saving intervention; IABP-SHOCK II (2012) showed no mortality benefit for routine IABP in cardiogenic shock, making routine IABP insertion before PCI not supported.
• C) Dobutamine alone (inotrope) does not address the primary problem of coronary occlusion; it is used for haemodynamic support while arranging revascularisation but is not the first intervention.
• D) Routine IABP for ALL cardiogenic shock patients is not supported by evidence — IABP-SHOCK II was definitively negative for routine use; selective use in refractory shock is acceptable.
• E) IV fluid challenge is counterproductive in cardiogenic shock where the problem is pump failure, not hypovolaemia; fluids will worsen pulmonary oedema.

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• A) Fondaparinux is the preferred anticoagulant for initial medical management of NSTE-ACS (lowest bleeding, OASIS-5 superiority), but requires addition of UFH at the time of PCI to avoid catheter-related thrombus — it should not be used alone for emergent PCI.
• C) Bivalirudin (direct thrombin inhibitor) is an acceptable alternative to UFH at the time of PCI with reduced risk of HIT; it is a reasonable choice but UFH is more widely available and remains guideline-appropriate.
• D) LMWH (enoxaparin) is used for initial anticoagulation; switching from enoxaparin to UFH at PCI (crossover) increases bleeding risk unless the last enoxaparin dose was recent.
• E) Dabigatran is a NOAC used in AF anticoagulation and VTE — it has no role in the acute ACS/PCI anticoagulation pathway.

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• A) Excessive antiplatelet therapy increases bleeding but does not cause stent thrombosis; subtherapeutic (not excessive) antiplatelet therapy is the culprit.
• C) Statins have anti-platelet pleiotropy (mild anti-aggregation) but do not impair antiplatelet therapy effectiveness; statin-induced myopathy does not affect platelet function.
• D) Excessive anticoagulation is not a cause of stent thrombosis; thrombosis results from failure of anti-platelet (not anti-coagulant) therapy.
• E) Hypertension during PCI can rarely cause coronary dissection but is not a mechanism of late stent thrombosis occurring 3 days post-procedure.

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• A) Admission and angiography are reserved for rule-in (high troponin or significant delta rise) or observe (intermediate) categories, not rule-out.
• C) A 3-hour troponin is part of the 0h/3h algorithm; the 0h/1h algorithm is the faster protocol and does not require a 3-hour sample if rule-out criteria are met at 1 hour.
• D) Immediate PCI is not indicated for rule-out troponin; it is reserved for true rule-in NSTEMI with high-risk features.
• E) Unstable angina (UA) is defined as ACS without troponin rise; this patient's troponins are both below the URL with minimal delta — rule-out applies, and routine DAPT is not started without confirmed ACS.

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• A) Clopidogrel is inferior to ticagrelor post-STEMI (PLATO: ticagrelor reduced MACE by 16% vs. clopidogrel); absence of beta-blocker and ACEi makes this regimen incomplete.
• B) This regimen is mostly correct but omits eplerenone, which provides additional mortality benefit in post-MI patients with EF ≤ 40% and HF/diabetes per EPHESUS.
• D) Warfarin has no routine role post-STEMI unless there is a specific indication (AF, LV thrombus, prosthetic valve); warfarin replaces, not supplements, DAPT in most scenarios.
• E) Beta-blocker and ACEi are both Class I post-STEMI medications; omitting them leaves the patient unprotected against adverse remodelling, arrhythmias, and further MACE.

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• A) STEMI with spontaneous reperfusion would typically show troponin elevation (even if delayed); completely negative troponin ×2 with no obstructive CAD is not consistent with true STEMI.
• C) Takotsubo (stress) cardiomyopathy causes transient apical ballooning on echo with mild troponin rise; it typically occurs in postmenopausal women after emotional stress, and echo findings distinguish it.
• D) Demand ischaemia (Type 2 MI) requires an underlying precipitant (sepsis, tachycardia, severe anaemia) and typically shows troponin elevation; it does not cause transient ST elevation with normal coronary anatomy.
• E) MINOCA from spontaneous coronary artery dissection (SCAD) is most common in young-middle-aged women and typically causes troponin rise with an MI pattern rather than entirely negative biomarkers.

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• A) LAD occlusion causes anterior STEMI (ST elevation in V1–V4), not inferior STEMI; mid-LAD lesions may also cause aVL changes.
• B) LCx occlusion can cause inferior MI (particularly in left-dominant systems) but more typically produces lateral or inferolateral changes (V5–V6, I, aVL); pure inferior STEMI with aVL depression is more typical of RCA.
• D) Left main occlusion causes catastrophic haemodynamic collapse with ST elevation in aVR and global ST depression — not an isolated inferior STEMI pattern.
• E) Diagonal branches supply the anterior free wall of the LV; diagonal occlusion causes anterolateral changes (I, aVL, V5–V6), not inferior changes.

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• A) High-sensitivity troponin is far more sensitive for MI detection than CK-MB; troponin rises earlier (1–3 hours) and is more specific for myocardial injury.
• C) CK-MB is not exclusively cardiac — it is also found in skeletal muscle, diaphragm, uterus, and small intestine; troponin T and I are more cardiac-specific.
• D) CK-MB returns to baseline within 36–48 hours, in stark contrast to troponin which may remain elevated for 7–14 days; this short window is precisely why it is useful for reinfarction diagnosis.
• E) CK-MB level does not differentiate STEMI from NSTEMI — differentiation is based on ECG (ST elevation vs. no ST elevation), not biomarker type.

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• A) Doubling the clopidogrel dose does not overcome CYP2C19 poor metaboliser status; the metabolic block is not overcome by higher doses in homozygous loss-of-function carriers.
• C) Omeprazole is actually a CYP2C19 inhibitor that further reduces clopidogrel conversion to active metabolite — it worsens the problem and should ideally be replaced by pantoprazole in patients on clopidogrel.
• D) Aspirin monotherapy alone provides inadequate protection post-ACS/PCI compared to DAPT; downgrading to single antiplatelet therapy is not appropriate without a compelling bleeding indication.
• E) Cilostazol is used in peripheral artery disease and has some antiplatelet properties, but it is not a guideline-recommended P2Y12 alternative in ACS and does not substitute for ticagrelor/prasugrel.

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• A) PCI in three-vessel disease with severely reduced EF provides incomplete revascularisation and lacks the survival data of CABG; SYNTAX and STICH trials both favour CABG in this scenario.
• C) Reduced EF is not a contraindication to CABG; in fact, patients with ischaemic cardiomyopathy and viable myocardium (hibernating myocardium) derive the greatest survival benefit from surgical revascularisation.
• D) Heart transplantation is considered only after optimisation of medical and surgical options; a patient with symptomatic CAD and angina who has not been revascularised should be offered CABG first.
• E) CRT/biventricular pacing treats dyssynchrony in HF with wide QRS but does not address obstructive CAD as the cause of her angina; it is not a bridging intervention for revascularisation.

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• A) Loop diuretics relieve congestion symptoms but do not improve mortality; digoxin reduces HF hospitalisations marginally (DIG trial) but does not reduce mortality and is no longer a pillar of GDMT.
• C) ACEi + ARB combination is not recommended (dual RAAS blockade increases hyperkalaemia and renal failure without additive mortality benefit — ONTARGET); ACEi should be replaced by ARNI, not combined with ARB.
• D) Ivabradine (SHIFT trial) reduces HF hospitalisation in patients with sinus rhythm and HR ≥ 70 despite beta-blocker but is not a first-line pillar; ARB is inferior to ARNI.
• E) Digoxin has no mortality benefit in HFrEF and is not included in the 2023 ESC HF GDMT quadruple regimen; ARNI has replaced ACEi as the RAS modulator of choice.

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• A) Sacubitril/valsartan is the standard for HFrEF (EF ≤ 40%) from PARADIGM-HF; EF 60% classifies this as HFpEF, not HFrEF.
• C) HFmrEF is defined as EF 41–49%; this patient's EF is 60%, clearly in the HFpEF range; the full GDMT quadruple therapy evidence base is primarily for HFrEF.
• D) Cardiac amyloidosis would require tissue diagnosis (biopsy or technetium bone scan for ATTR); there is no clinical history suggesting this — LVH with hypertension is a far more common cause of HFpEF.
• E) This is chronic HF with stable hypertension, not a hypertensive emergency; IV labetalol is for acute hypertensive crises with end-organ damage, not for outpatient HFpEF management.

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• A) Same-day switching from ACEi to ARNI is dangerous and contraindicated — the resulting accumulation of bradykinin can cause severe, potentially fatal angioedema.
• B) A 12-hour washout is insufficient given that some ACEi (e.g., enalaprilat, lisinopril) have longer half-lives; 36 hours ensures adequate clearance of the ACEi effect.
• D) A 7-day washout is excessive and unnecessarily delays beneficial therapy; the PARADIGM-HF trial used 36 hours as the mandatory washout period.
• E) A 1-month washout is unnecessarily prolonged and delays initiation of a mortality-reducing therapy without additional safety benefit.

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• A) Amiodarone is an antiarrhythmic used for AF and ventricular arrhythmias; it is not indicated for rate reduction in sinus rhythm HFrEF and has multiple extracardiac toxicities (thyroid, lung, liver).
• B) Digoxin is used in HFrEF with AF to control ventricular rate; in sinus rhythm, DIG trial showed modest reduction in HF hospitalisations but no mortality benefit; it is not preferred over ivabradine for HR reduction.
• D) Verapamil (non-dihydropyridine CCB) has negative inotropic effects and is contraindicated in HFrEF — it worsens systolic function and is associated with increased mortality.
• E) Dronedarone is also contraindicated in HFrEF (EF < 35%) — the ANDROMEDA trial showed increased mortality; it is not to be used in systolic HF.

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• A) Morphine as first-line is now discouraged — observational data (ADHERE registry, ALARM-HF) show morphine in APO is associated with increased need for mechanical ventilation and higher mortality; it is the classic HKMLE trap in this scenario.
• C) High-dose morphine as the first intervention is the trap — modern guidelines caution against routine morphine use in APO; it causes respiratory depression, vomiting, and haemodynamic instability.
• D) BiPAP is used when CPAP fails or when hypercapnia is present; amiodarone has no role in hypertensive APO without arrhythmia; digoxin is not acute therapy for APO.
• E) Vasopressors (adrenaline, norepinephrine) are for cardiogenic shock with hypotension — this patient is hypertensive at 180/100 and needs vasodilation, not vasopressors.

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• A) IV sodium nitroprusside is a potent arteriovenous dilator used in hypertensive emergencies and severe MR/AR; it requires arterial line monitoring and is not first-line for standard ADHF with borderline BP.
• C) Hydralazine IM is used in hypertensive emergencies (e.g., eclampsia); it is not standard therapy for acute decompensated HF and causes reflex tachycardia.
• D) IV enalaprilat causes unpredictable BP drops and is no longer recommended for acute HF management; oral ACEi/ARNI are preferred once stabilised.
• E) GTN can be used with caution when SBP 90–100 mmHg, especially when the patient is symptomatic with pulmonary congestion; absolute withholding of vasodilators at this BP threshold is overly conservative without clinical benefit.

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• A) Low-dose dopamine ("renal-dose") for renoprotection in HF has been definitively discredited — DOPAMINE trial (part of ROSE-AHF) showed no benefit; it does not protect renal function and increases arrhythmia risk.
• C) Adrenaline (epinephrine) is a vasopressor + inotrope reserved for cardiac arrest or refractory shock; it causes significant tachycardia, lactic acidosis, and arrhythmias at inotropic doses — not first-line for ADHF.
• D) Vasopressin (V1A agonist) addresses peripheral vasodilation but has no direct inotropic effect; it is not appropriate as sole therapy in cardiogenic shock where the primary problem is low CO.
• E) Levosimendan (calcium sensitiser + K-ATP channel opener) is an intravenous inotrope with vasodilatory properties that may be considered in selected ADHF, but SURVIVE and REVIVE trials showed no mortality benefit over dobutamine, and it is not recommended as first-line for all cardiogenic shock.

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• A) ICD alone addresses sudden cardiac death prevention but does not improve haemodynamics or symptoms from dyssynchrony; in a patient with wide LBBB QRS, CRT is additionally needed to resynchronise ventricular contraction.
• C) CRT-P without defibrillator capability is considered when ICD implantation is not desired (e.g., elderly frail patients, patient preference, limited life expectancy) or when SCD risk is judged low — but CRT-D is preferred in this otherwise fit 60-year-old with EF 25%.
• D) pLVAD (e.g., Impella) is used for acute haemodynamic support in cardiogenic shock or high-risk PCI — not for stable NYHA III HFrEF on GDMT.
• E) Waiting until NYHA class IV is too late — CRT has the largest benefit in NYHA II–III; NYHA IV patients have limited survival benefit and device implantation carries procedural risk.

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• A) BNP > 35 pg/mL is the non-acute rule-out threshold (in stable outpatients), not the rule-in threshold; using 35 as rule-in would grossly overdiagnose HF given BNP rises with age, renal failure, and AF.
• C) BNP is a front-line diagnostic biomarker and is specifically recommended as the initial test for suspected HF before or alongside echocardiography; it helps triage patients for urgent echo.
• D) BNP > 500 as the only rule-in threshold is too high; many patients with significant HF have BNP between 100–500 pg/mL; guidelines use 100 pg/mL as the acute rule-in threshold.
• E) BNP can paradoxically be LOWER in obese patients (adipose tissue clears natriuretic peptides); HFpEF often has lower BNP than HFrEF for equivalent symptoms — they are not equivalent.

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• A) K⁺ 5.8 mEq/L is dangerously elevated and requires action; deferring review for 3 months risks life-threatening hyperkalaemia and arrhythmia.
• C) Stopping both spironolactone AND ACEi removes two mortality-reducing pillars of GDMT; the goal is to manage hyperkalaemia while maintaining RAAS therapy, not to discontinue it.
• D) IV calcium gluconate (membrane stabilisation) is used for acute severe hyperkalaemia with ECG changes (peaked T waves, wide QRS, sine wave) — K⁺ 5.8 with no ECG changes does not require emergency IV calcium.
• E) Furosemide does promote kaliuresis but is not a substitute for RAAS-targeted GDMT; it reduces congestion but has no mortality benefit in HFrEF and cannot replace spironolactone or ACEi.

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• A) While DAPA-HF did show a reduction in CV death, the primary endpoint was the composite including HF hospitalisations/urgent visits; all-cause mortality was not the primary endpoint.
• C) The glycaemic benefit was a secondary finding; the primary endpoint was cardiovascular/HF, and the benefit was present independent of diabetes status — SGLT2i in HF is now a cardiac drug, not just a diabetes drug.
• D) DAPA-HF did not demonstrate AF reduction as a primary outcome; some SGLT2i trials have suggested atrial benefit but this is not the established primary benefit in HFrEF.
• E) SGLT2 inhibitors do not reduce ACS events in the same way as antiplatelet/anticoagulant therapy; their benefit in HF is through haemodynamic, renal, and cardiac metabolic mechanisms, not anti-ischaemic effects.

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• B) NYHA II indicates symptoms on moderate exertion; class IV is the most severe functional class with rest symptoms; increasing beta-blocker in a decompensated NYHA IV patient can worsen haemodynamics.
• C) NYHA I represents no functional limitation; ivabradine targets patients in NYHA II–III with HR ≥ 70 bpm in sinus rhythm; it is not the answer for advanced HF.
• D) NYHA I denotes symptoms only on vigorous activity; class IV is the opposite end of the spectrum requiring advanced HF evaluation.
• E) Palliative care is appropriate for patients who decline or are ineligible for advanced therapies, but should not be the default without first considering LVAD or transplantation in an otherwise eligible patient.

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• A) HFrEF (systolic HF) presents with reduced EF, cold/clammy peripheries (low CO), and narrow pulse pressure — the opposite haemodynamic profile to high-output states.
• C) Cardiogenic shock is a low-output (low CO, high SVR) state with cold peripheries and hypotension; this patient has elevated CO and warm extremities.
• D) HFpEF involves impaired diastolic filling with preserved systolic function; it does not typically cause elevated CO and low SVR, which are hallmarks of high-output states.
• E) Constrictive pericarditis causes impaired ventricular filling with low-output features (Kussmaul's sign, pericardial knock, equalization of diastolic pressures) — not high-output physiology.

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• A) Initiating beta-blockers in a patient with active fluid retention and haemodynamic instability (ADHF) is dangerous and guideline-contraindicated; ESC 2023 HF guidelines specify that beta-blockers should only be started in stable patients who are euvolaemic.
• C) Beta-blockers (carvedilol, bisoprolol, metoprolol succinate) are a Class I, LOE A recommendation for all HFrEF patients with EF ≤ 35% — they dramatically reduce mortality by 34% (MERIT-HF, COPERNICUS); contraindication applies only to acute decompensation.
• D) Full therapeutic doses (e.g., carvedilol 25 mg BD, bisoprolol 10 mg) cause severe hypotension and bradycardia if started without titration; gradual up-titration over weeks is mandatory.
• E) IV beta-blockers (e.g., IV metoprolol) are used in acute arrhythmia management, not for initiating long-term HF therapy; oral preparations are used for GDMT.

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• A) Both CV mortality (HR 0.80) and HF hospitalisation were significantly reduced — the trial showed both components of the composite were independently significant.
• C) PARADIGM-HF was terminated early due to overwhelming superiority; sacubitril/valsartan was definitively not equivalent to enalapril.
• D) While PARADIGM-HF did show reduction in SCD (sudden death), this was not the primary endpoint and hospitalisation was also robustly reduced — separating the two components misrepresents the trial.
• E) The benefit was seen regardless of diabetes status; the trial included both diabetic and non-diabetic patients with consistent benefit across subgroups.

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• B) Upper lobe diversion plus Kerley B lines in the context of HF history and symptoms cannot be attributed to COPD; COPD causes hyperinflation and flattened diaphragms, not upper lobe diversion.
• C) Upper lobe diversion (vascular redistribution) on an erect PA film is distinctly abnormal, indicating elevated pulmonary venous pressure (PCWP 12–18 mmHg); it is NOT a normal variant.
• D) Kerley B lines are short horizontal lines at lung bases representing thickened interlobular septa from interstitial oedema; lymphangitis carcinomatosa can cause similar lines but in a HF clinical context, they represent pulmonary oedema.
• E) Cardiomegaly is defined as a cardiothoracic ratio > 0.5 (not 0.6) on a standard PA chest radiograph; a ratio > 0.6 indicates severe cardiomegaly but the threshold for clinical cardiomegaly is 0.5.

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• A) CRT-P addresses dyssynchrony but provides no defibrillation capability; in a patient with VT and EF 28%, defibrillation capability is essential — CRT-D would be appropriate if QRS criteria also met, but isolated CRT-P is insufficient.
• C) The wearable cardioverter-defibrillator is a temporary bridge (e.g., during 90-day waiting period for new cardiomyopathy, post-MI) — it is not a permanent long-term solution.
• D) Amiodarone reduces VT burden and may reduce SCD rate, but in direct comparison, ICD is superior for SCD prevention; SCD-HeFT demonstrated ICD > amiodarone for reducing all-cause mortality in HFrEF (HR 0.77 for ICD vs. no benefit for amiodarone).
• E) ICD is indicated for BOTH secondary prevention (post-arrest, sustained VT) AND primary prevention (EF ≤ 35%, NYHA II–III on GDMT, life expectancy > 1 year); restricting to post-arrest survivors misses a large population who benefit from ICD.

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• B) EMPA-REG OUTCOME was a CV outcomes trial in T2DM with established CVD; it showed CV mortality benefit (predominantly through HF reduction) but enrolled diabetic patients broadly, not specifically HFpEF; it is not the trial that specifically proved benefit in HFpEF.
• C) DECLARE-TIMI 58 (dapagliflozin in T2DM) reduced HF hospitalisation but was a diabetes outcomes trial, not a dedicated HF trial; it did not specifically include HFpEF-defined patients.
• D) DELIVER (dapagliflozin in HFpEF, Solomon et al., NEJM 2022) actually confirmed benefit — dapagliflozin reduced worsening HF or CV death by 18% (HR 0.82) — this distractor is the reverse of the true finding.
• E) EMPEROR-Preserved specifically enrolled HFpEF patients (EF > 40%); the companion trial EMPEROR-Reduced enrolled HFrEF; they are not interchangeable.

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• A) Increasing oral furosemide doses in the presence of bowel oedema is ineffective due to unpredictable and markedly reduced bioavailability; switching to IV is the solution, not dose escalation of the oral form.
• C) NSAIDs inhibit prostaglandin synthesis, causing renal vasoconstriction, worsening sodium retention, and directly inhibiting diuretic efficacy; they are absolutely contraindicated in HF.
• D) Discontinuing diuretics in a patient with severe fluid overload and refractory congestion would cause life-threatening respiratory compromise; diuretics remain essential for decongestion management.
• E) Digoxin does not improve renal perfusion; its mechanism is Na/K-ATPase inhibition leading to positive inotropy; it is not indicated as a renal adjunct and can be nephrotoxic in the context of impaired renal function.

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• A) HFrEF requires reduced LVEF (< 40%); this patient's EF is 60% — LV systolic function is preserved; GDMT (beta-blocker, ARNI, MRA, SGLT2i) for HFrEF is not indicated without reduced EF.
• C) HFpEF by definition involves preserved LV EF with evidence of diastolic dysfunction; while her EF is 60%, the dominant picture is right-sided pathology requiring investigation for pulmonary hypertension or pericardial disease rather than being classified as HFpEF.
• D) Takotsubo presents acutely with apical ballooning after emotional/physical stress, typically with transient systolic dysfunction and troponin rise — it does not cause chronic 3-month progressive oedema and tricuspid regurgitation.
• E) Hypertensive heart disease causes LV hypertrophy and diastolic dysfunction (HFpEF pattern); it does not cause severe tricuspid regurgitation and isolated RV dilation as the primary finding.

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• A) IV digoxin is the safest rate control agent in ADHF with AF — it is mildly inotropic (positive inotropy via Na/K-ATPase inhibition) and reduces ventricular rate without negative inotropic effect; it is the preferred agent in decompensated HF with AF.
• B) IV amiodarone is used for rapid AF with haemodynamic compromise when cardioversion is not immediately feasible; it provides both rate and rhythm control without significant negative inotropic effect, making it acceptable in decompensated HF.
• D) IV diltiazem (non-dihydropyridine CCB) is contraindicated in HFrEF due to negative inotropy, similar to verapamil; it is not the safest choice but is less immediately dangerous than IV beta-blocker — however both are to be avoided.
• E) Rate control in AF with rapid ventricular response is important in ADHF as persistent tachycardia worsens cardiac output and promotes tachycardia-induced cardiomyopathy; rate control is necessary.

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• B) Stage B requires demonstrable structural cardiac disease (e.g., LV hypertrophy on echo, prior MI, reduced EF); this patient has risk factors but no documented structural abnormality.
• C) Stage C requires both structural heart disease AND current or past symptoms of HF — neither condition is met in this asymptomatic patient.
• D) Stage D represents the most advanced, refractory HF requiring specialist intervention (LVAD, transplant); this patient is pre-HF by definition.
• E) NYHA class I is a functional classification applied to patients who already have established HF with no limitation; ACC/AHA Stage A applies to patients who have not yet developed HF, which is a different concept.

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• A) > 50% pacing is far below the threshold for effective CRT; patients with 50% biventricular pacing derive no meaningful haemodynamic benefit.
• B) > 75% is still insufficient — the 98% threshold comes from observational and device-based studies showing that even brief periods of intrinsic ventricular conduction negate resynchronisation.
• D) 100% at all times is ideal but not achievable in every patient; 98–99% is the practical clinical target; aiming for 100% should not delay device optimisation.
• E) Pacing percentage is critically important — a patient "non-responding" to CRT should have pacing percentage checked first as it is a common and correctable cause of CRT non-response.

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• A) Waiting for symptoms before initiating GDMT wastes the opportunity to prevent adverse myocardial remodelling; SOLVD-P demonstrated that enalapril reduced progression to symptomatic HF even in asymptomatic LV dysfunction.
• C) Genetic testing is appropriate for familial DCM evaluation but does not substitute for medical therapy; relatives with reduced EF require treatment regardless of genetic confirmation.
• D) Prophylactic amiodarone is not recommended and increases extracardiac toxicity without proven mortality benefit in asymptomatic cardiomyopathy; ICD is superior to amiodarone for SCD prevention in HFrEF.
• E) LVAD is reserved for Stage D/NYHA IV refractory HF — this asymptomatic patient with EF 35% is far from requiring mechanical circulatory support.

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• A) Immediate intubation and invasive ventilation are reserved for patients who are unconscious, unable to cooperate, have respiratory failure refractory to NIV, or have a contraindication to NIV; an alert, cooperative patient should receive CPAP/NIV first.
• B) HFNC delivers humidified oxygen at high flow rates and provides minimal CPAP (~5 cmH₂O) but is inferior to CPAP/BiPAP for acute cardiogenic pulmonary oedema with severe hypoxia; it is not the optimal choice.
• D) BiPAP (CPAP + pressure support) is preferred when there is hypercapnia (Type 2 respiratory failure) or when the patient cannot generate adequate inspiratory effort; pure cardiogenic pulmonary oedema typically involves Type 1 (hypoxic) failure, where CPAP is equally effective and easier to use (3CPO: BiPAP did not outperform CPAP in cardiogenic APO).
• E) Non-rebreather mask delivers up to 70–80% FiO₂ but provides no positive airway pressure; SpO₂ of 88% on high-flow oxygen warrants escalation to pressure support, not simply a different oxygen mask.

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Summary Table

Question Distribution by Subtopic

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HKMLE Trap Answers Summary

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Guideline & Trial Reference Map