Miscellaneous

1351395 - Athletes decrease right ventricular volumes more than sedentary individuals during exercise—an exercise real-time cardiac magnetic resonance imaging study

Thursday, January 26, 2023

4:30 PM – 5:10 PM

Location: Pacific Jewel

Presenting Author(s)

Björn Östenson, MD

PhD Student
Clinical Physiology, Department of Clinical Sciences Lund, Lund University, Skåne University Hospital, Lund, Sweden.
Lund, Skane Lan, Sweden

Primary Author(s)

Björn Östenson, MD

PhD Student
Clinical Physiology, Department of Clinical Sciences Lund, Lund University, Skåne University Hospital, Lund, Sweden.
Lund, Skane Lan, Sweden

Co-Author(s)

Ellen Ostenfeld, MD, PhD

Associate professor
Lund University
Lund, Skane Lan, Sweden
JE

Jonathan Edlund, MD

MD
Lund University, Skåne University Hospital
Lund, Skane Lan, Sweden
HA

Håkan Arheden, MD, PhD

Professor
Lund University
Lund, Sweden
KS

Katarina Steding-Ehrenborg, PhD

Associate Professor
Lund University, Skane University Hospital
Lund, Skane Lan, Sweden

Background: The athlete’s heart has enlarged cardiac chambers with preserved systolic and diastolic function at resting condition (1,2). However, there are conflicting results regarding the physiological mechanisms causing augmented cardiac output during exercise. Therefore, the aim of this study was to investigate the mechanisms of increased cardiac output from rest to exercise in athletes and sedentary controls using exercise cardiac magnetic resonance imaging (CMR).

Methods: Seventeen endurance-trained athletes (8 females) and 10 sedentary, healthy controls (6 females) matched for age and sex underwent exercise CMR using an MR-compatible cycle ergometer (Lode BV, Groningen, The Netherlands) in a 1.5 T scanner (Siemens Aera, Siemens Healthineers, Erlangen, Germany). Standard short-axis cine images were acquired at rest covering the whole heart and 2-, 3 and 4-chamber long-axes. Real-time bSSFP sequences were used during steady-state moderate and vigorous exercise defined as 60% and 80% of expected maximal heart rate (bpm) calculated as 220-age. Image analysis was performed using Segment v3.3 (Medviso AB, Lund, Sweden) (3). Real-time images were analyzed at end-expiration using a validated semi-automatic sorting algorithm to control for respiratory influence on cardiac volume measurements (4). Mean left ventricular (LV) and right ventricular (RV) end-diastolic volume (EDV) and end-systolic volume (ESV) were calculated. Differences in LV and RV parameters between groups and intensities were assessed by two-way mixed model ANOVA with a post-hoc Tukey test (IBM SPSS Statistics 25, SPS inc., Chicago, Illinois, USA) and significance level was set to < 0.05.

Results: As expected, athletes had larger LVEDV (231 ml vs 182 ml, p< 0.05) and RVEDV (245 ml vs 181 ml, p< 0.05) at rest. Athletes maintained LVEDV throughout moderate and vigorous exercise (rest: 231 ml; moderate intensity: 231 ml; vigorous intensity: 221 ml, p >0.05) while sedentary controls decreased slightly at moderate and vigorous intensities (rest: 182 ml; moderate intensity: 181 ml; vigorous intensity: 160 ml, p< 0.05 for rest vs both intensities, respectively). Both groups decreased LVESV during exercise (athletes at rest 106 ml and during vigorous intensity 84 ml, 21% change; sedentary controls at rest 89 ml and during vigorous intensity 60 ml, 32% change). Athletes decreased RVEDV (at rest 245 ml and during vigorous intensity 202 ml; 17% change) and RVESV (118 ml and 89 ml; 25% change) more than sedentary controls (RVEDV: at rest 181 ml and during vigorous intensity 169 ml, 7% change; RVESV: at rest 88 ml to 73 ml; 17% change) during exercise (p value for interaction effect < 0.05 for both).

Conclusion: Athletes decrease RVEDV and RVESV more than sedentary controls, while LVEDV and LVESV are not dependent on training status during exercise. These results may imply that the right, but not the left, ventricle act as a conduit in athletes, compared to sedentary controls.