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Haemodynamic comparison of amlodipine and atenolol in essential hypertension using the quantascope

T C Tham1, N Herity, S Guy

  • 1Department of Therapeutics and Pharmacology, Queen's University of Belfast, Belfast, Northern Ireland.

British Journal of Clinical Pharmacology
|December 1, 1993
PubMed

Insights

Amlodipine and atenolol effectively lowered blood pressure in hypertensive patients over three months. Amlodipine reduced cardiac work, while atenolol decreased heart rate, indicating distinct cardiovascular effects.

Area of Science:

  • Cardiovascular Pharmacology
  • Hypertension Management

Background:

  • Essential hypertension remains a significant global health concern.
  • Understanding the distinct cardiovascular effects of antihypertensive medications is crucial for effective treatment.

Purpose of the Study:

  • To compare the cardiovascular effects of amlodipine and atenolol in patients with essential hypertension over three months.
  • To elucidate the differing mechanisms of action of amlodipine (vasodilator) and atenolol (cardiac depressant).

Main Methods:

  • Utilized a non-imaging echo-Doppler cardiac output device employing the attenuated compensation volume flow (ACVF) principle.
  • Assessed cardiovascular parameters including mean arterial pressure, heart rate, stroke volume, and systemic vascular resistance in 24 hypertensive patients.
  • Evaluated treatment effects at 4 and 12 weeks.

Main Results:

  • Both amlodipine and atenolol significantly reduced mean arterial pressure similarly at 12 weeks.
  • Atenolol, but not amlodipine, decreased heart rate.
  • Amlodipine significantly reduced systemic vascular resistance and cardiac stroke work, whereas atenolol did not alter these parameters.
  • No significant changes were observed in skin nutrient flow or fingertip temperature with either drug.

Conclusions:

  • Amlodipine and atenolol exhibit distinct cardiovascular effects in hypertensive patients.
  • Amlodipine acts as a vasodilator, reducing cardiac stroke work, while atenolol decreases cardiac output by reducing heart rate.
  • The greater reduction in cardiac stroke work by amlodipine warrants further investigation in longer-term studies.

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