Changes in cardiac function after effective treatment of hypertensive emergencies with i.v. clonidine

Area of Science:

• Cardiology
• Pharmacology

Background:

• Hypertensive emergencies require prompt and effective blood pressure reduction.
• Intravenous medications are often necessary for rapid control.

Purpose of the Study:

• To evaluate the efficacy and safety of intravenous clonidine infusion for managing hypertensive emergencies.
• To assess the impact of clonidine on hemodynamics and cardiac performance.

Main Methods:

• 12 patients with hypertensive emergencies received escalating doses of intravenous clonidine infusion.
• Blood pressure, vascular resistance, heart rate, and cardiac performance (ejection fraction, end-diastolic/systolic volumes) were monitored.
• Radionuclide angiocardiography was used to assess cardiac function.

Main Results:

• All patients achieved normalized blood pressure (mean BP ≤ 105 mmHg).
• Clonidine reduced total and lower limb vascular resistance, with a transient decrease in heart rate.
• Cardiac performance improved, evidenced by increased ejection fraction and reduced ventricular volumes.
• Mean dose was 382.5 ± 98.3 mcg over 26.5 ± 4.6 minutes; side effects (dry mouth, drowsiness) were mild and transient.

Conclusions:

• Intravenous clonidine is an effective and safe treatment for hypertensive emergencies.
• It normalizes blood pressure while improving cardiac function and reducing vascular resistance.