Changes in aortic distensibility and pulse wave velocity assessed with magnetic resonance imaging following beta-blocker therapy in the Marfan syndrome

Am J Cardiol. 1998 Jul 15;82(2):203-8. doi: 10.1016/s0002-9149(98)00315-4.

Abstract

It has been shown that beta-adrenergic blocking agents may reduce the rate of aortic root dilation and the development of aortic complications in patients with the Marfan syndrome. This may be due to beta-blocker-induced changes in aortic stiffness, of which distensibility and pulse wave velocity are in vivo measurable derivatives. We studied changes in distensibility at 4 levels of the aorta and pulse wave velocity along the entire aorta after 2 weeks of beta-blocker therapy in 6 Marfan syndrome patients and in 6 healthy volunteers, using magnetic resonance imaging (MRI) combined with brachial artery blood pressure measurements. In both groups, mean blood pressure decreased significantly (Marfan: 86 +/- 6 vs 78 +/- 5 mm Hg, p <0.05; control: 80 +/- 8 vs 73 +/- 3 mm Hg, p <0.05) (all data expressed as mean +/- 1 SD). At baseline, the Marfan syndrome patients exhibited decreased distensibility at the level of the ascending aorta (2 +/- 1 vs 6 +/- 2 10(-3)mm Hg(-1), p <0.01) and increased pulse wave velocity (6.2 +/- 0.4 vs 3.9 +/- 0.4 ms(-1), p <0.01) compared with control subjects. Only the Marfan syndrome patients had a significant increase in aortic distensibility at multiple levels and a significant decrease in pulse wave velocity after beta-blocker therapy (ascending aorta distensibility: 2 +/- 1 vs 4 +/- 1 10(-3)mm Hg(-1), p <0.05; abdominal aorta distensibility: 5 +/- 2 vs 8 +/- 3 10(-3)mm Hg(-1), p <0.05; pulse wave velocity: 6.2 +/- 0.4 vs 5.0 +/- 1.0 ms(-1), p <0.05). Thus, aortic stiffness in Marfan syndrome, together with mean blood pressure, is reduced by beta-blocker therapy, and MRI is well suited to detect these changes by measuring distensibility and pulse wave velocity.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adrenergic beta-Antagonists / therapeutic use*
  • Adult
  • Age Factors
  • Aorta / drug effects*
  • Aorta / physiopathology*
  • Atenolol / therapeutic use
  • Blood Pressure / drug effects
  • Case-Control Studies
  • Female
  • Heart Rate / drug effects
  • Humans
  • Magnetic Resonance Imaging*
  • Male
  • Marfan Syndrome / drug therapy*
  • Marfan Syndrome / physiopathology*
  • Metoprolol / therapeutic use
  • Middle Aged
  • Pulsatile Flow / drug effects*
  • Vasodilation / drug effects

Substances

  • Adrenergic beta-Antagonists
  • Atenolol
  • Metoprolol