USMLE Prep - Medical Reference Library

Post‑MI Secondary Prevention — Medications & Cardiac Rehab

System: Cardiology • Reviewed: Aug 31, 2025 • Step 1Step 2Step 3

Synopsis:

Post‑MI care: DAPT after PCI, high‑intensity statin, beta‑blocker, ACEi/ARB (± MRA if EF ≤40%), smoking cessation, BP/DM control, and enrollment in cardiac rehab; consider ezetimibe/PCSK9i if LDL‑C ≥70.

Key Points

  • Stabilize ABCs; begin targeted evaluation without delaying life-saving therapy.
  • Use system-specific risk tools to guide testing and disposition.
  • Order high-yield tests first; escalate imaging when indicated.
  • Start evidence-based initial therapy and reassess frequently.

Algorithm

  1. Primary survey and vitals; IV access and monitors.
  2. Focused history/physical; identify red flags and likely etiologies.
  3. Order system-appropriate labs and imaging (see Investigations).
  4. Initiate guideline-based empiric therapy (see Pharmacology).
  5. Reassess response; arrange consultation and definitive management.

Clinical Synopsis & Reasoning

For Post Mi Secondary Prevention Medications Cardiac Rehab, frame the differential by acuity and pathophysiology, then align diagnostics to the leading hypotheses. Prioritize stabilization while obtaining high‑yield studies such as EKG (Rhythm/ischemia), Troponin (Myocardial injury), CXR (Pulmonary edema/size), BMP/Mg2+ (Electrolytes/renal). Incorporate bedside imaging and targeted labs to define severity and identify complications; synthesize results with clinical trajectory to refine the working diagnosis and disposition needs.


Treatment Strategy & Disposition

Initiate disease‑directed therapy alongside supportive care, titrating to objective response. Pharmacologic options commonly include Aspirin, P2Y12 inhibitor, Heparin/LMWH, Beta-blocker. Use validated frameworks (e.g., Core Post‑MI Medications) to guide escalation and site of care. Address precipitating factors, de‑escalate empiric therapies with data, and arrange follow‑up for monitoring and risk‑factor modification; admit patients with instability, high risk of deterioration, or needs for close monitoring.


Epidemiology / Risk Factors

  • Atherosclerotic risk (HTN, DM, HLD, smoking)
  • Age/family history of premature CAD

Investigations

TestRole / RationaleTypical FindingsNotes
EKGRhythm/ischemiaST-T changes/arrhythmiaSerial
TroponinMyocardial injuryDynamic rise/fallTrend
CXRPulmonary edema/sizeCardiomegaly/edema
BMP/Mg2+Electrolytes/renalDerangements
CBC/CoagsBleeding riskAbnormal/INR

Core Post‑MI Medications

ClassIndicationNotes
AntiplateletsPost‑PCI DAPTDuration individualized
StatinAll patientsHigh‑intensity preferred
Beta‑blockerAll unless contraindicatedReduce mortality/arrhythmia
ACEi/ARBLV dysfunction/diabetes/CKDStart early, titrate
MRAEF ≤40% with HF/DMMonitor K+/Cr

Pharmacology

MedicationMechanismOnsetRole in TherapyLimitations
AcetaminophenAnalgesic/antipyreticHoursSymptom control as appropriateHepatotoxicity (overdose)
Ondansetron5-HT3 antagonismMinutesAntiemesis if neededQT prolongation

Prognosis / Complications

  • Prognosis by ischemic burden/LV function
  • Arrhythmias and HF are complications

Patient Education / Counseling

  • Explain red flags and when to seek emergent care.
  • Reinforce medication adherence and follow-up plan.

Secondary Prevention Notes

Ensure adherence and manage adverse effects. Consider SGLT2i/GLP‑1 RA in diabetics with ASCVD. Plan DAPT duration with cardiology considering ischemic vs bleeding risk.


References

  1. ACC/AHA STEMI/NSTEMI Guidelines — Link