Hemodynamic effects of cadralazine or chlorthalidone in verapamil-treated elderly hypertensives

Area of Science:

• Cardiology
• Geriatrics
• Pharmacology

Background:

• Elderly patients with hypertension often require combination therapy.
• Verapamil monotherapy may not adequately control blood pressure in all older adults.

Purpose of the Study:

• To evaluate the efficacy and hemodynamic effects of adding cadralazine or chlorthalidone to verapamil in elderly hypertensives.
• To compare cadralazine and chlorthalidone as second-step treatments.

Main Methods:

• A double-blind, crossover study involving 14 hypertensive patients (aged 66-77 years) inadequately controlled by verapamil 240 mg SR.
• Patients received either cadralazine 10 mg or chlorthalidone 25 mg daily for 1 month each, added to verapamil.
• Echo-Doppler hemodynamics were assessed at baseline, after verapamil, and after each crossover phase.

Main Results:

• Both cadralazine and chlorthalidone significantly reduced diastolic blood pressure (DBP) in supine and upright positions.
• A satisfactory DBP response (< or = 90 mmHg or reduction > or = 10 mmHg) was achieved in 9 patients with cadralazine and 9 with chlorthalidone.
• Hemodynamic analysis in responders indicated that both drugs reduced peripheral resistances without inducing reflex tachycardia.

Conclusions:

• Cadralazine and chlorthalidone are suitable second-step treatments for elderly hypertensives not controlled by verapamil monotherapy.
• Both agents effectively reduce total peripheral resistance (TPR), contributing to blood pressure lowering.