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Left Ventricular Unloading with Calcium Antagonists

  • M. D. Guazzi
Part of the Ettore Majorana International Science Series book series (volume 21)

Summary

Calcium. channel blockers reduce the arterial smooth muscle tone and lower blood pressure. They may be regarded as left ventricular (LV) unloading agents.

LV unloading efficacy of nifedipine (15 cases) and verapamil (14 cases) was tested in hypertensive decompensated patients, through a one-month treatment period.

Nifedipine persistently reduced systemic vascular resistance (SVR), mean arterial pressure (MAP), mean pulmonary wedge pressure (PWP) and LV diastolic diameter (DD) and improved cardiac index and Vcf. All of the patients had relief from dyspnea and reduction in heart size. The only side effect was ankle edema in 6 cases.

Verapamil reduced SVR and MAP was not effective on PWP, LV, DD and Vcf. The drug was discontinued in 2 patients who developed severe dyspnea at rest after a 3–4 day continued oral treatment. Clinical symptoms and signs did not improve in the remaining subjects despite persistent pressure reduction.

A less potent vasodilating action of verapamil and a prominent depression in cardiac contractility may account for the different results with the two compounds, in spite of a shared vasodilating antihypertensive effect. These findings prove that functional changes in the failing hypertensive heart may differ from one calcium blocker to another as a result of interaction and relative preponderance of influences on afterload and contractility.

Keywords

Mean Arterial Pressure Systemic Vascular Resistance Wall Stress Peripheral Vascular Resistance Diastolic Diameter 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Plenum Press, New York 1985

Authors and Affiliations

  • M. D. Guazzi
    • 1
  1. 1.Cardiovascolari “G. Sisini”, Centro Ricerche Cardiovascolari del Consiglio Nazionale delle RicercheUniversity of MilanMilanItaly

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