What antihypertensive medications should be avoided in a patient with hypertensive emergency and acute coronary syndrome (ACS)?

Antihypertensive Medications to Avoid in Hypertensive Emergency with Acute Coronary Syndrome

Beta-blockers are contraindicated in hypertensive emergency with ACS when there is moderate-to-severe left ventricular failure with pulmonary edema, bradycardia (<60 bpm), hypotension (SBP <100 mmHg), poor peripheral perfusion, second- or third-degree heart block, or reactive airways disease. 1

First-Line Treatments for Hypertensive Emergency with ACS

• Esmolol and nitroglycerin are the agents of choice for acute coronary syndromes with hypertensive emergency 1
• Labetalol and nicardipine are also preferred medications for managing hypertensive emergency with ACS 1

Medications to Avoid in Hypertensive Emergency with ACS

Beta-Blockers (Contraindicated in specific situations):

• Avoid in patients with moderate-to-severe LV failure with pulmonary edema 1
• Avoid in bradycardia (<60 bpm) 1
• Avoid in hypotension (SBP <100 mmHg) 1
• Avoid in poor peripheral perfusion 1
• Avoid in second- or third-degree heart block 1
• Avoid in reactive airways disease or COPD 1

Hydralazine:

• Unpredictability of response and prolonged duration of action make hydralazine undesirable as first-line agent 1, 2

Sodium Nitroprusside:

• Should be used with caution in ACS as it may decrease regional blood flow in patients with coronary abnormalities 1
• Can increase myocardial damage after acute myocardial infarction 1
• Should be used for as short a duration as possible due to risk of cyanide toxicity 1

Immediate-Release Nifedipine:

• Should not be administered to patients with NSTE-ACS in the absence of beta-blocker therapy 1
• Can cause reflex tachycardia which may worsen myocardial ischemia 1

ACE Inhibitors:

• Contraindicated in pregnancy and should not be used in acute MI or bilateral renal artery stenosis 1
• Relatively slow onset of action (15 min) and unpredictability of BP response make them less suitable for hypertensive emergencies 1

General Principles for BP Management in ACS

• Avoid rapid and excessive lowering of DBP to <60 mmHg as this may reduce coronary perfusion and worsen ischemia 1
• BP should be lowered slowly, with a target reduction of no more than 25% within the first hour 1
• For patients without compelling conditions, aim for BP of 160/100 mmHg within the next 2-6 hours after initial reduction 1
• Cautiously normalize BP during the following 24-48 hours 1
• The balance between myocardial oxygen supply and demand is crucial in ACS patients 1

Special Considerations

• Patients with ACS often have vasomotor instability with increased tendency to exaggerated responses to antihypertensive therapy 1
• Continuous infusion of short-acting titratable antihypertensive agents is often preferable to prevent further target organ damage 1
• Intra-arterial BP monitoring is recommended to prevent "overshoot" hypotension, especially with potent IV agents 1
• Nitrates given in the presence of PDE-5 inhibitors may induce profound hypotension 1

By carefully selecting appropriate antihypertensive medications and avoiding contraindicated agents, clinicians can effectively manage hypertensive emergencies in ACS patients while minimizing risks of worsening ischemia or other complications.