Should lisinopril (angiotensin-converting enzyme inhibitor) be withheld before stress tests to prevent hypotension?

Lisinopril Does Not Need to Be Withheld Before Stress Tests

Lisinopril does not need to be withheld before stress tests as there is no evidence that it causes clinically significant hypotension during stress testing. 1

Mechanism of Action and Hemodynamic Effects

• Lisinopril is an orally active, nonsulfhydryl angiotensin-converting enzyme (ACE) inhibitor that reduces blood pressure by inhibiting ACE activity, thereby reducing plasma angiotensin II and aldosterone 2
• During stress testing, lisinopril effectively reduces both systolic and diastolic blood pressure without altering the hemodynamic profile and may even attenuate vasoconstriction during stress 1
• The antihypertensive effect of lisinopril begins within 2 hours, peaks around 6 hours, and lasts for at least 24 hours 2

Evidence for Safety During Stress Tests

• Research specifically examining lisinopril during stress tests found that it effectively reduced blood pressure during various stressful events without causing adverse hemodynamic responses 1
• In a controlled study, patients on lisinopril were able to complete stress tests safely with the medication reducing both resting and stress-induced blood pressure elevations 3
• The 2024 AHA/ACC perioperative cardiovascular management guidelines do not list ACE inhibitors among medications that need to be discontinued before stress testing 4

Stress Test Contraindications and Precautions

• The contraindications for stress testing listed in guidelines include:
  • Acute coronary syndrome
  • Decompensated heart failure
  • Severe/symptomatic aortic stenosis
  • Uncontrolled arrhythmia
  • Severe systemic arterial hypertension (≥200/110 mm Hg)
  • Acute aortic dissection
  • Pericarditis/myocarditis
  • Pulmonary embolism
  • Severe pulmonary hypertension 4
• ACE inhibitors like lisinopril are not included in these contraindications 4

Special Considerations

• While routine continuation of lisinopril is appropriate, caution should be exercised in patients with:
  • Renal failure
  • Hyperkalemia
  • Known history of hypotension 4
• Patients taking multiple antihypertensive medications, especially when combined with other drugs that can cause hypotension, may require individualized assessment 5
• For patients with poor left ventricular function, monitoring during the stress test is particularly important, though ACE inhibitors are generally beneficial in this population 4

Clinical Approach

• Continue lisinopril before stress tests in most patients 1
• Ensure adequate hydration before the test to prevent dehydration-related hypotension 3
• Monitor blood pressure before, during, and after the stress test as standard practice 4
• For exercise stress testing, lisinopril's effect may actually be beneficial by attenuating excessive blood pressure responses 1
• For pharmacological stress tests (vasodilator or dobutamine), there is no evidence that lisinopril needs to be withheld 4

In conclusion, the available evidence does not support withholding lisinopril before stress tests. Research shows that lisinopril is safe during stress testing and may even provide beneficial effects by moderating stress-induced blood pressure increases 1, 3.