Screen for life-threatening causes FIRST. Any red flag requires immediate escalation.
Why red-flag screening matters: Chest pain accounts for 1-2% of GP consultations but includes conditions with 30-day mortality >10% if missed (STEMI 10%, aortic dissection 20-30%, massive PE 15%). Time-to-treatment directly impacts outcomes: door-to-balloon <90 minutes reduces STEMI mortality by 25%. Aortic dissection mortality increases 1% per hour. The goal is not to diagnose definitively but to identify who needs immediate hospital assessment. NICE CG95 emphasizes that clinical judgement overrides scoring systems—if it feels wrong, escalate. Missing ACS in a 45-year-old costs 30+ years of life; over-cautious transfer of MSK pain costs 4 hours. The asymmetry justifies liberal 999 use.
Use clinical features and validated tools to stratify risk. Document clearly in notes.
Why risk stratification matters: Only 10-15% of chest pain in primary care is cardiac. Sending everyone to ED creates 4-8 hour waits, raises anxiety, and costs £150+ per attendance. Clinical features have validated likelihood ratios: radiation to both arms (LR+ 7.1), diaphoresis (LR+ 2.0), chest wall tenderness (LR- 0.3). Wells score has 98% NPV at low-risk cut-off—missing 2% is acceptable when balanced against imaging 50+ patients. Pain diaries reveal patterns invisible in a snapshot consultation: exertional angina appears as 5-10 minute episodes triggered by identical activities. QRISK3 >10% means 1-in-10 will have a cardiovascular event within 10 years without intervention—these patients need lower thresholds for investigation. Documentation protects you medico-legally and guides the next clinician.
Classify based on examination and risk assessment. Most diagnoses are clinical.
Why classification drives management: Treatment pathways diverge completely based on cause. Stable angina requires antiplatelet + statin + beta-blocker ± revascularization. GORD requires PPI + lifestyle. Costochondritis requires reassurance + NSAIDs. Giving a PPI to angina delays diagnosis by 6 weeks and risks an MI. Giving aspirin to GORD causes bleeding without benefit. The key skill is not memorizing rare causes but recognizing the big 5: cardiac (10%), MSK (30%), GI (20%), respiratory (15%), psychological (15%). Most are benign—only 1-2% are ACS—but that 1-2% is why we exist. Classification also sets follow-up intervals: cardiac needs 2-week cardiology review; MSK can wait 4-6 weeks. Accurate labeling reduces patient anxiety (costochondritis sounds less scary than "chest pain of unknown cause") and prevents re-consultations.
Focused examination to confirm or refute differential diagnoses. Takes 3-5 minutes.
Why examination findings change management: Examination has two purposes: (1) exclude emergencies that need same-day transfer, (2) build confidence in a benign diagnosis. A pericardial rub confirms pericarditis and avoids a troponin (saves £30 + patient anxiety). Reproducible chest wall tenderness LR- 0.3 makes ACS less likely but does NOT exclude it (Cochrane review 2010)—combine with history and ECG. Unilateral leg swelling + pleuritic pain raises Wells score to 6.5 (PE likely) and triggers imaging. BP differential >20 mmHg has 96% sensitivity for dissection. The exam is not diagnostic—it shifts probabilities. A normal exam in a high-risk patient (diabetes, 60 years old, crushing pain) still needs investigation. An abnormal exam in a low-risk patient (25, no risk factors, sharp pain) might be costochondritis. Context is everything.
Targeted investigations based on clinical suspicion. Avoid blanket testing.
Why investigations need clear indications: An ECG costs £1 but prevents a £500 ED admission if it shows STEMI. A normal ECG does NOT exclude ACS (10-15% of STEMIs have initial normal ECG) but combined with low-risk features reduces probability from 5% to <1%. CXR has 2WW indications (NICE NG12): persistent symptoms + smoking in over-40s has 2-3% lung cancer prevalence. D-dimer sensitivity 95% but specificity 50%—in a 70-year-old post-op patient, it will be elevated regardless of PE, creating false reassurance if negative (missed PE) or unnecessary CTPA if positive (radiation + contrast risk). Lipid testing guides primary prevention: QRISK3 10% = NNT 50 over 10 years to prevent one event with statins (atorvastatin 20 mg reduces events by 30%). Troponin requires serial samples 3-6 hours apart—GP cannot do this, hence same-day hospital transfer if ACS suspected. The key question: will this test change my management today? If no, defer to specialist.
Clear thresholds for when specialist input is needed. Document referral rationale.
Why referral thresholds matter: RACPC was designed to reduce inappropriate ED attendances and speed access to diagnostics for stable angina—most see patients within 2 weeks and have direct access to CTCA. National Audit of Cardiac Rehabilitation shows 30-40% of stable angina can be managed medically without revascularization, but you need cardiology input to confirm. 2WW lung referrals have 5-7% cancer pick-up rate (NICE NG12 data)—missing one lung cancer in a 55-year-old smoker costs 10+ years of life; over-referring 20 patients to find it is acceptable. Same-day PE referrals prevent death (untreated PE has 30% mortality; treated <5%). Primary care management of costochondritis saves 200+ ED visits per 100,000 population per year—reassurance + NSAIDs is effective for 90% within 2 weeks. The skill is triaging accurately: send sick patients fast, manage well patients locally, and document why you chose your pathway.
Treatment depends on underlying diagnosis. This section covers primary care management after exclusion of emergencies.
Why treatment ladders improve outcomes: Stable angina medical therapy (aspirin + statin + beta-blocker) reduces cardiovascular events by 60% before any revascularization is considered. Beta-blockers reduce angina frequency by 50% (NNT 2.5 for symptom control). GTN terminates angina within 5 minutes in 80% of episodes—failure to respond is a red flag for ACS. High-dose atorvastatin (80 mg) is proven superior to 10 mg in ACS trials (PROVE-IT: 16% additional risk reduction). GORD: PPI trial is both diagnostic and therapeutic—70% resolution confirms GORD; failure prompts endoscopy/cardiology. Costochondritis: reassurance is as important as NSAIDs—natural history is resolution within 2-4 weeks in 90%. Over-medicalizing MSK pain increases anxiety and re-consultation rates. Anxiety chest pain: CBT has NNT 3 (better than most drugs) and no side effects. SSRIs take 6-8 weeks but reduce panic attacks by 60-70%. The error is treating everyone the same—individualize to diagnosis.
Lifestyle modification is first-line treatment for cardiovascular risk and equivalent to pharmacotherapy for many conditions.
Why lifestyle is treatment, not advice: Smoking cessation reduces post-MI mortality by 50%—more than any single drug. Mediterranean diet in PREDIMED trial reduced cardiovascular events by 30% (NNT 33 over 5 years), comparable to statins (NNT 30). Exercise reduces all-cause mortality by 25%—no drug achieves this. Weight loss 10 kg reduces systolic BP by 10 mmHg (equivalent to adding a second antihypertensive). The error is relegating lifestyle to a leaflet—it should be prescribed like a drug with specific targets, follow-up, and referral to services (Stop Smoking, weight management, cardiac rehab). Stop Smoking Services achieve 15% quit rates vs 3% willpower-alone. Cardiac rehab reduces readmissions by 30% (saves NHS £2,000+ per patient). The challenge is adherence: 50% drop out of lifestyle programs. Motivational interviewing, written action plans, and follow-up calls improve adherence to 60-70%. Quantify the benefit: "Stopping smoking will halve your heart attack risk" is more powerful than "Smoking is bad for you."
Structured follow-up prevents missed deterioration. Clear safety-netting empowers patients to re-present appropriately.
Why follow-up and safety-netting save lives: 10-15% of ACS present initially with atypical symptoms and normal ECG—these patients re-present within 7 days with classic features. Early follow-up (1 week) catches this subgroup. GORD non-responders at 4 weeks include 2-3% with malignancy (especially age >55)—hence step-up to endoscopy. Costochondritis that persists >4 weeks may be rib fracture, Tietze's, or referred cervical spine pain—reassessment changes diagnosis in 10%. SSRIs increase suicidal ideation in first 2 weeks in <1% (especially under-30s)—hence 2-week review is mandatory. Safety-netting reduces re-consultation anxiety ("I don't want to bother the GP") while preventing inappropriate re-presentations ("Is this normal?"). Specific triggers ("pain at rest, GTN ineffective") are clearer than vague advice ("come back if worried"). The medico-legal protection is secondary but real—"Patient advised to re-attend if symptoms persist beyond 2 weeks" is documented evidence of safe practice. Annual cardiovascular reviews reduce events by 20% via medication adherence + risk factor control (NICE CG181).