From the Guidelines
Hydralazine is not the preferred agent for managing hypertension in patients with acute ischemic cerebrovascular accident (CVA), and its use should be considered only as a second-line option. In the context of acute ischemic stroke, blood pressure management is crucial, and the goal is to avoid rapid or excessive lowering of blood pressure, which may worsen cerebral ischemia by reducing perfusion to the penumbra 1. The 2024 ESC guidelines for the management of elevated blood pressure and hypertension recommend careful acute blood pressure lowering with i.v. therapy to <180 mmHg in patients with systolic BP ≥220 mmHg, and suggest the use of i.v. labetalol, oral methyldopa, or nifedipine as first-line options, with intravenous hydralazine as a second-line option 1.
The disadvantages of hydralazine in this setting include its unpredictable hypotensive effects, reflex tachycardia, which may increase myocardial oxygen demand, and a relatively long duration of action, making it difficult to reverse excessive blood pressure reduction 1. Additionally, hydralazine can cause headache and dizziness, which may complicate neurological assessment in stroke patients. In contrast, intravenous labetalol, nicardipine, or clevidipine are preferred agents due to their predictable dose-response relationship and short half-lives, allowing for precise titration 1.
If blood pressure management is required after the acute phase, oral antihypertensives can be initiated or resumed, typically starting 24-48 hours after stroke onset, with careful monitoring and gradual titration to avoid hypoperfusion. The choice of antihypertensive agent should be individualized, taking into account the patient's comorbidities, renal function, and other factors. However, in the acute setting, hydralazine should not be the first choice for managing hypertension in patients with acute ischemic CVA, and its use should be reserved for specific situations where first-line options are not available or contraindicated 1.
Some key points to consider when managing hypertension in patients with acute ischemic CVA include:
- Avoiding rapid or excessive lowering of blood pressure
- Using first-line agents such as i.v. labetalol, oral methyldopa, or nifedipine
- Considering hydralazine as a second-line option
- Monitoring blood pressure closely and adjusting treatment as needed
- Individualizing the choice of antihypertensive agent based on patient-specific factors.
From the FDA Drug Label
It should be used with caution in patients with cerebral vascular accidents. The FDA drug label indicates that hydralazine should be used with caution in patients with cerebral vascular accidents, such as acute ischemic cerebrovascular accident (CVA), due to its potential to cause myocardial stimulation and increased pulmonary artery pressure.
- The label does not provide a clear indication for use in hypertension in patients with acute ischemic CVA.
- However, it advises caution when using the drug in such patients 2.
From the Research
Hydralazine Use in Hypertension with Acute Ischemic CVA
- Hydralazine is not the primary recommended agent for managing hypertension in patients with acute ischemic cerebrovascular accident (CVA) 3.
- The use of hydralazine in this context is mentioned in a study comparing the effects of labetalol, nicardipine, and hydralazine on time to target blood pressure before alteplase administration in patients with acute ischemic stroke 4.
- This study found that the median time to blood pressure control was 15 minutes in the hydralazine group, compared to 10 minutes in the labetalol group and 22 minutes in the nicardipine group 4.
- Another study characterized the incidence of poor neurologic outcome in patients treated with alteplase for AIS who received antihypertensive medications, including hydralazine, prior to and within the first 24 hours following alteplase administration 5.
- Hydralazine was used in 22% of patients in this study, with intravenous push labetalol being the most commonly administered agent (81.2%) and nicardipine being used in 44.1% of patients 5.
- The optimal antihypertensive regimen for controlling blood pressure before alteplase therapy remains unclear, with controversies surrounding the speed and goals of treatment 6.
Considerations for Hydralazine Use
- The decision to use hydralazine or other antihypertensive agents in patients with acute ischemic CVA should be based on individual patient factors and clinical judgment 3, 4, 5.
- It is essential to balance the need to control blood pressure with the risk of compromising cerebral perfusion and worsening outcomes 3, 6.
- Further research is necessary to establish the safety and efficacy of antihypertensive treatment in patients with acute ischemic stroke and to determine the optimal target reduction in blood pressure 6.