Author + information
- Rory B. Weiner,
- Stephanie K. Isaacs,
- Francis Wang,
- Brant Berkstresser,
- Thomas Wang,
- Adolph Hutter,
- Gregory Lewis,
- Michael Picard and
- Aaron Baggish
Although structural components of exercise–induced cardiac remodeling (i.e. athlete's heart) are well documented, functional characteristics are not well defined. We examined the myocardial response to intravascular volume challenge in endurance athletes (EA) and sedentary controls.
EA (n=12, age 18.9±0.5 yrs) with eccentric left ventricular (LV) hypertrophy (LV mass=118±16 g/m2; RWT=0.33±0.04) and sedentary controls (n=8, age 25±3 yrs) with normal LV geometry (LV mass index=68±18 g/m2; RWT=0.36±0.05) were administered large volume normal saline infusion (1200mL × BSA over 2 hours). Speckle–tracking echocardiography was used to assess myocardial mechanics at rest and immediately after volume challenge.
Saline infusion produced similar increases in stroke volume (SV) in EA (11.9±1.2 ml) and controls (11.7±1.4 ml). However, SV augmentation in EA was associated with significantly less increase in myocardial mechanical parameters (Table). Further, calculation of LV end–systolic meridional wall stress showed that EA augment SV at a lower energy cost than controls (Table).
Intravascular volume challenge produced similar increase in SV in EA with eccentric LV hypertrophy and sedentary controls. However, the remodeled hearts of EA accomplished this volume augmentation with less increase in myocardial mechanics and end–systolic wall stress. These results provide novel insight into the functional adaptive correlates of the athlete's heart.
Poster Sessions, Expo North
Sunday, March 10, 2013, 3:45 p.m.–4:30 p.m.
Session Title: Sports and Exercise Cardiology: New Insights into the Functional Alternations of the Athlete's Heart
Abstract Category: 30. Sports and Exercise Cardiology: Sports Medicine
Presentation Number: 1261–257
- 2013 American College of Cardiology Foundation