On this page
Study tools
Write your answer
Saved on this device. No marking — you are the marker.
Stem
A 38-year-old man presents to the cardiology outpatient department with a 4-month history of progressive exertional dyspnoea (now NYHA class III — dyspnoea walking on the flat), orthopnoea using three pillows, paroxysmal nocturnal dyspnoea, fatigue, and bilateral ankle swelling. He drinks roughly half a bottle of whisky daily and has done so for 10 years. He smokes 20 cigarettes per day. There is no history of chest pain, palpitations or syncope. His father died suddenly at age 49 of unknown cause.
On examination: pulse 96/min irregularly irregular, BP 110/70 mmHg, JVP elevated 6 cm above the sternal angle, apex beat displaced to the 6th intercostal space, anterior axillary line and diffuse in character. Auscultation reveals a soft pansystolic murmur at the apex radiating to the axilla and a third heart sound. Bibasal inspiratory crackles are present. There is pitting ankle oedema to the mid-shin. The liver is enlarged 3 cm below the costal margin.
ECG: atrial fibrillation at 96/min, left bundle branch block, QRS 130 ms, non-specific T-wave flattening in lateral leads. Chest X-ray: cardiothoracic ratio 0.6, upper-lobe blood diversion, small bilateral pleural effusions. Echocardiography: dilated left ventricle (LVEDD 6.6 cm), global hypokinesis, ejection fraction 28%, functional mitral regurgitation, no LV thrombus, dilated left atrium. Coronary angiography: normal coronary arteries.
Questions
a) What is the most likely diagnosis, and state the defining criteria? (2 marks)
Diagnosis: dilated cardiomyopathy (alcoholic), in atrial fibrillation, with decompensated heart failure with reduced ejection fraction (HFrEF). The defining criteria (per the 2016 ESC position statement, Pinto et al.) are left ventricular dilatation (LVEDD greater than 117% of the value predicted for age and body surface area by the Henry formula — 112% is the 2-SD cut-off, 117% adds specificity) and an ejection fraction under 45% (or fractional shortening under 25%), not explained by abnormal loading conditions (hypertension, valve disease) or coronary artery disease. This patient meets criteria (LVEDD 6.6 cm, EF 28%, normal coronaries) and the heavy alcohol history identifies a likely aetiology.
b) Outline the structured aetiological differential you must work through before accepting the label 'idiopathic', listing at least six causes with the discriminating test for each. (3 marks)
- Genetic / familial (30 to 50% of DCM; usually autosomal-dominant; truncating TTN variants the single largest gene, in about 25% of familial and 18% of sporadic cases) — three-generation family history + targeted next-generation sequencing panel.
- Myocarditis (viral — coxsackie, parvovirus B19, SARS-CoV-2, HIV; autoimmune) — cardiac MRI (subepicardial inferolateral LGE, oedema on T2; Lake Louise criteria); endomyocardial biopsy if giant-cell suspected.
- Alcohol — history (the classic cohort drank at least 100 g of ethanol per day for 10 years or more); LVEF improves with abstinence, or with reduction to no more than 60 g per day, and deteriorates if intake stays above 80 g per day.
- Anthracycline / trastuzumab — chemotherapy history; cumulative doxorubicin dose over 400 mg/m2.
- Peripartum — timing (last month of pregnancy to 5 months postpartum); titin genetics shared with DCM.
- Tachycardia-induced — persistent tachyarrhythmia (AF with uncontrolled rate, or a high PVC burden: above 24% is the best discriminator, with reversible dysfunction reported from 10% upwards); Holter; recovery with rate/rhythm control.
- Infiltrative / metabolic / endocrine — haemochromatosis (ferritin, transferrin saturation, HFE gene); sarcoidosis (CMR patchy LGE, FDG-PET, serum ACE); thyroid disease (TSH, free T4); iron deficiency (ferritin, transferrin saturation).
- Chagas disease (Trypanosoma cruzi) — serology in those from or who have travelled to Latin America; apical aneurysm.
- Neuromuscular — Duchenne/Becker (X-linked dystrophin); creatine kinase.
c) Detail the stepwise pharmacological management, naming each drug with class, target dose, and rationale, and explain the temporal relationship between diuresis and initiation of beta-blockade. (3 marks)
First decongest with an IV loop diuretic (furosemide 40 to 80 mg IV) and oxygen, sitting upright. Once euvolaemic and haemodynamically stable, initiate the four pillars of HFrEF at low dose, titrating to target every 2 to 4 weeks:
- ARNI (sacubitril/valsartan) start 49/51 mg twice daily, target 97/103 mg twice daily, OR ACE-inhibitor (ramipril target 5 mg twice daily, enalapril 10 to 20 mg twice daily, lisinopril 20 to 35 mg daily) — blocks RAAS; reduces mortality, hospitalisation, and remodelling. ACE-inhibitor-to-ARNI switch needs a 36-hour washout to prevent angioedema.
- Beta-blocker (carvedilol target 25 mg twice daily — 50 mg twice daily if over 85 kg — or bisoprolol 10 mg daily, or metoprolol succinate 200 mg daily) — blocks sympathetic overdrive; reduces mortality. Never start a beta-blocker in a decompensated, congested patient — decongest first.
- Mineralocorticoid receptor antagonist (spironolactone 12.5 to 50 mg daily) — blocks aldosterone-mediated fibrosis; reduces mortality. Monitor potassium and creatinine at 1, 4, 8 weeks.
- SGLT2 inhibitor (dapagliflozin 10 mg daily) — reduces mortality and hospitalisation independent of diabetes.
Plus anticoagulation for the atrial fibrillation (CHA2DS2-VASc indicates DOAC such as apixaban 5 mg twice daily; warfarin if contraindicated). Alcohol abstinence is mandatory and offers the best chance of recovery.
d) Outline the indications for device therapy (ICD, CRT) and the specific caveat raised by the DANISH trial for this patient. (2 marks)
- ICD for primary prevention: LVEF 35% or less, NYHA II to III, expected to survive substantially longer than 1 year with good functional status, after at least 3 months of optimal medical therapy (reassessment is critical — EF may recover, particularly in alcoholic DCM). In the 2021 ESC heart-failure guideline this is Class I in ischaemic disease but only Class IIa in non-ischaemic disease, which is the class that applies here.
- CRT (cardiac resynchronisation therapy), by the same guideline: Class I for QRS 150 ms or more with left bundle branch block and EF 35% or less in sinus rhythm; Class IIa for QRS 130 to 149 ms with LBBB or non-LBBB with QRS 150 ms or more; not indicated below 130 ms. This patient's QRS is 130 ms and he is in AF, so a Class I CRT indication is not met.
- DANISH trial (NEJM 2016): among 1116 patients (556 ICD, 560 usual care), ICD implantation did not reduce all-cause mortality in non-ischaemic systolic heart failure (21.6% vs 23.4%; HR 0.87) even though sudden cardiac death was halved; the prespecified age analysis found the survival benefit confined to patients aged 70 or under. The decision must involve shared decision-making, taking into account age, comorbidity, life-expectancy, family history (his father's sudden death at 49 raises the possibility of genetic DCM — genetic testing and cascade screening are warranted), CMR LGE pattern and Holter findings.