O-18: Sildenafil (Viagra®) improves the elastic properties of the aorta

Abstract

Sildenafil (S) is a new, effective drug for erectile dysfunction. However, the effect of S on the mechanics of large arteries has not been investigated. Aortic elastic properties are important determinants of left ventricular function and coronary blood flow and have been identified as prognosticators of cardiovascular risk.

To investigate the effect of S on aortic elastic properties we studied 27 pts (age 69±9 years) with risk factors for erectile dysfunction both at baseline (BL) and after oral administration of 50 mg of S, as well as at BL and after placebo. Carotid-femoral pulse wave velocity (PWV) was measured as an index of aortic elasticity. PWV (=dL/dt, where dL is the distance travelled by the pulse and dt the time delay between the corresponding foot of pulse waves) was measured using an automated, non-invasive device (Complior®) that has been previously validated.

S led to a decrease in PWV (by 5.2%, fig.) which denotes improvement of aortic elastic properties. This effect was prolonged and lasted throughout the period of measurements (3 hours). This effect was accompanied by a decrease in systolic and diastolic pressure (by 10.7 and 9.1 mmHg respectively; P<0.001 for both).

Sildenafil leads to an improvement of the elastic properties of the aorta. This finding has implications on left ventricular function and coronary blood flow and provides a new insight into the effects of sildenafil on the cardiovascular system.

Consultant - Astra Zeneca, Solvay, Bristol-Myer Squibbs, Pfizer Major Stock Shareholder - PWV Medical Pty. Limited, Sydney, Australia (See Figure)

Pulse Wave Velocity, Aortic Stiffness, Sildenafil