Inferior STEMI with Hypotension and Bradycardia
62-year-old man with 45 minutes of crushing substernal pressure radiating to both jaws, nausea, and diaphoresis. He is pale and clammy. HR 48 and regular, BP 84/50, RR 20, SpO2 93% on room air; he is alert but anxious. The 12-lead shows 3 mm ST elevation in II, III, and aVF with reciprocal depression in I and aVL. He chewed his own 325 mg aspirin before you arrived. History includes hypertension and an MI 6 years ago; he denies taking erectile dysfunction medication. The nearest PCI center is 35 minutes away; a community hospital that gives fibrinolytics is 10 minutes away.
1. Why is nitroglycerin the wrong drug here, even though he has classic ischemic chest pain?
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Three reasons stack up against nitro in this patient:
- Systolic BP is 84 mmHg - nitro is contraindicated in hypotension (generally SBP <90 or >30 below baseline).
- Inferior STEMI with hypotension suggests right ventricular involvement. The RV is preload-dependent; venodilation drops preload and can crash the pressure further.
- Bradycardia with hypotension already signals poor perfusion, and nitro can worsen both.
Also confirm no recent phosphodiesterase inhibitor use. Since he denies it, that is not the limiting factor - the pressure and the infarct location are.
2. Outline your treatment sequence over the next 10 minutes, including what you would do if atropine fails.
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- Oxygen only to keep SpO2 94-99%; he is 93%, so titrate low-flow.
- IV access and a cautious fluid bolus - 250 mL isotonic, reassess BP and lung sounds, repeat once if tolerated. In RV infarction, volume is the main preload support.
- Atropine 0.5 mg IV for symptomatic bradycardia with hypotension and poor perfusion; repeat every 3-5 minutes to a total of 3 mg.
- If atropine fails or he deteriorates, move to transcutaneous pacing at a rate of about 60-70, titrating milliamps to capture, and treat pain/discomfort as able.
- Avoid nitroglycerin, and do not give large fluid volumes if lung sounds become wet.
- Reassess perfusion (mental status, skin, radial pulse) after every intervention, not just the monitor.
3. Do you transport to the 10-minute hospital or the 35-minute PCI center? Defend the choice.
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Go to the PCI center, provided he can be stabilized enough for the extra road time. Thirty-five minutes is well inside the acceptable window for primary PCI, which is the superior reperfusion strategy when it can be delivered promptly. The community hospital offers fibrinolysis, but fibrinolysis is less effective and carries bleeding risk - and this patient is hypotensive and bradycardic, a high-risk picture in which a failed lytic has no rescue available locally.
Decision modifiers to state explicitly:
- If he becomes unstable to the point of peri-arrest (refractory hypotension, worsening bradycardia, need for ongoing pacing), the 10-minute hospital becomes the safer destination for stabilization.
- Notify the PCI center early with the 12-lead findings so the cath lab is activated.
- His aspirin is already given; do not delay transport to give anything else.