A 58-year-old man from Delhi presents to the emergency department with chest pain for 3 hours. He describes the pain as substernal, pressure-like, radiating to the left arm, and associated with diaphoresis. He has a history of hypertension and type 2 diabetes. On examination, blood pressure is 128/82 mmHg, heart rate 92 bpm, and respiratory rate 18/min. An ECG obtained at presentation shows ST-segment depression of 2 mm in leads II, III, and aVF, with T-wave inversion in the same leads. Troponin I measured at 3 hours is 0.8 ng/mL (normal <0.04 ng/mL). A repeat troponin at 6 hours is 2.1 ng/mL. What is the most appropriate next step in management?

Explanation

## Diagnosis and Risk Stratification **Key Point:** This patient has NSTEMI (Non-ST Elevation Myocardial Infarction) confirmed by: - Acute coronary syndrome symptoms (substernal chest pain with radiation) - ECG changes: ST-segment depression and T-wave inversion in inferior leads (suggesting inferior wall ischemia) - Elevated and rising troponin (0.8 → 2.1 ng/mL) indicating myocardial necrosis ## Risk Assessment This patient meets **high-risk criteria** for NSTEMI: - Troponin elevation (>0.04 ng/mL) - Dynamic ECG changes (ST depression + T inversion) - Diabetes mellitus (increases risk) - Age >55 years **High-Yield:** According to current guidelines (ESC 2020, ACC/AHA), high-risk NSTEMI patients should undergo **early invasive strategy** with coronary angiography within **2–3 hours** of presentation. ## Dual Antiplatelet Therapy (DAPT) | Drug | Rationale | Dosing | |------|-----------|--------| | Aspirin | Irreversible COX inhibition; reduces mortality | 300–500 mg loading | | Ticagrelor OR Clopidogrel | P2Y₁₂ inhibitor; ticagrelor preferred in ACS | Ticagrelor 180 mg; Clopidogrel 600 mg | **Clinical Pearl:** Ticagrelor is preferred over clopidogrel in acute NSTEMI because it provides faster and more potent platelet inhibition, reducing cardiovascular death and MI recurrence [cite:ESC ACS Guidelines 2020]. ## Anticoagulation **Key Point:** Unfractionated heparin (UFH) or enoxaparin should be initiated immediately. UFH is preferred if PCI is anticipated within hours (easier reversal with protamine). ## Timing of Angiography ```mermaid flowchart TD A[NSTEMI Confirmed]:::outcome --> B{Risk Stratification}:::decision B -->|High Risk| C[Angiography within 2-3 hours]:::action B -->|Intermediate Risk| D[Angiography within 24 hours]:::action B -->|Low Risk| E[Angiography within 72 hours]:::action C --> F[PCI ± stent]:::action D --> F E --> F ``` **High-Yield:** High-risk NSTEMI (troponin+, ST depression, diabetes) = **early invasive strategy within 2–3 hours**. This patient qualifies because of troponin elevation, dynamic ECG changes, and diabetes.