A 71-year-old man with hypertension and type 2 diabetes presents to the emergency department with inferior ST-elevation myocardial infarction (STEMI). His vital signs on arrival are: blood pressure 148/92 mmHg, heart rate 88 bpm, respiratory rate 16/min. ECG shows ST elevations in leads II, III, and aVF with reciprocal changes. Troponin I is 4.2 ng/mL. After initiation of dual antiplatelet therapy and emergent cardiac catheterization, the patient develops severe bradycardia (heart rate 38 bpm), hypotension (82/54 mmHg), and second-degree atrioventricular block on repeat ECG. The patient was given intravenous metoprolol 5 mg × 3 doses prior to this complication. Which of the following beta-blockers would have posed the LOWEST risk of precipitating conduction system abnormalities in the acute phase of inferior STEMI?
- A)Esmolol—ultra-short-acting, beta-1 selective with rapid reversibilityGABARITO
- B)Metoprolol—beta-1 selective with moderate duration of action
- C)Propranolol—non-selective with membrane-stabilizing properties
- D)Sotalol—non-selective with Class III antiarrhythmic activity
- E)Carvedilol—non-selective with alpha-blocking and vasodilatory effects
Explicação
Esmolol is an ultra-short-acting, intravenous, beta-1 selective agent with a half-life of ~9 minutes. In acute inferior STEMI, where atrioventricular conduction abnormalities are common (due to ischemia of the AV nodal artery from RCA occlusion), esmolol's rap... Ver explicação completa e trilha adaptativa →