Changes in dynamic left ventricular function, assessed by the strain-volume loop, relate to reverse remodeling after aortic valve replacement

J Appl Physiol (1985). 2019 Aug 1;127(2):415-422. doi: 10.1152/japplphysiol.00190.2019. Epub 2019 Jun 27.

Abstract

Aortic valve replacement (AVR) leads to remodeling of the left ventricle (LV). Adopting a novel technique to examine dynamic LV function, our study explored whether post-AVR changes in dynamic LV function and/or changes in aortic valve characteristics are associated with LV mass regression during follow-up. We retrospectively analyzed 30 participants with severe aortic stenosis who underwent standard transthoracic echocardiographic assessment before AVR [88 (IQR or interquartile range: 22-143) days], post-AVR [13 (6-22) days], and during follow-up [455 (226-907) days]. We assessed standard measures of LV structure, function, and aortic valve characteristics. Novel insight into dynamic LV function was provided through a four-chamber image by examination of the temporal relation between LV longitudinal strain (ε) and volume (ε-volume loops), representing the contribution of LV mechanics to volume change. AVR resulted in immediate changes in structural valve characteristics, alongside a reduced LV longitudinal peak ε and improved coherence between the diastolic and systolic part of the ε-volume loop (all P < 0.05). Follow-up revealed a decrease in LV mass (P < 0.05) and improvements in LV ejection fraction and LV longitudinal peak ε (P < 0.05). A significant relationship was present between decline in LV mass during follow-up and post-AVR improvement in coherence of the ε-volume loops (r = 0.439, P = 0.03), but not with post-AVR changes in aortic valve characteristics or LV function (all P > 0.05). We found that post-AVR improvements in dynamic LV function are related to long-term remodeling of the LV. This highlights the potential importance of assessing dynamic LV function for cardiac adaptations in vivo.NEW & NOTEWORTHY Combining temporal measures of left ventricular longitudinal strain and volume (strain-volume loop) provides novel insights in dynamic cardiac function. In patients with aortic stenosis who underwent aortic valve replacement, postsurgical changes in the strain-volume loop are associated with regression of left ventricular mass during follow-up. This provides novel insight into the relation between postsurgery changes in cardiac hemodynamics and long-term structural remodeling, but also supports the potential utility of the assessment of dynamic cardiac function.

Keywords: LV mechanics; aortic valve replacement; cardiac adaptation; echocardiography; ultrasound.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aortic Valve / physiopathology*
  • Aortic Valve Stenosis / physiopathology
  • Diastole / physiology
  • Echocardiography / methods
  • Female
  • Heart Ventricles / physiopathology*
  • Hemodynamics / physiology
  • Humans
  • Male
  • Retrospective Studies
  • Stroke Volume / physiology*
  • Systole / physiology
  • Ventricular Function, Left / physiology*