Left and right ventricular longitudinal strain-volume/area relationships in elite athletes.

We propose a novel ultrasound approach with the primary aim of establishing the temporal relationship of structure and function in athletes of varying sporting demographics. 92 male athletes were studied [Group IA, (low static-low dynamic) (n = 20); Group IC, (low static-high dynamic) (n = 25); Group IIIA, (high static-low dynamic) (n = 21); Group IIIC, (high static-high dynamic) (n = 26)]. Conventional echocardiography of both the left ventricles (LV) and right ventricles (RV) was undertaken. An assessment of simultaneous longitudinal strain and LV volume/RV area was provided. Data was presented as derived strain for % end diastolic volume/area. Athletes in group IC and IIIC had larger LV end diastolic volumes compared to athletes in groups IA and IIIA (50 ± 6 and 54 ± 8 ml/(m(2))(1.5) versus 42 ± 7 and 43 ± 2 ml/(m(2))(1.5) respectively). Group IIIC also had significantly larger mean wall thickness (MWT) compared to all groups. Athletes from group IIIC required greater longitudinal strain for any given % volume which correlated to MWT (r = 0.4, p < 0.0001). Findings were similar in the RV with the exception that group IIIC athletes required lower strain for any given % area. There are physiological differences between athletes with the largest LV and RV in athletes from group IIIC. These athletes also have greater resting longitudinal contribution to volume change in the LV which, in part, is related to an increased wall thickness. A lower longitudinal contribution to area change in the RV is also apparent in these athletes

Report from the Annual Conference of the British Society of Echocardiography, November 2016, Queen Elizabeth II Conference Centre, London.

Peer reviewedPublisher PD

Alterations in Cardiac Mechanics Following Ultra-Endurance Exercise: Insights from Left and Right Ventricular Area-Deformation Loops.

BACKGROUND: The aim of this study was to use novel area-deformation (ε) loops to interrogate the interaction between the right ventricular (RV) and left ventricular (LV) mechanics following a 100-mile endurance run. METHODS: Fifteen participants (mean body mass, 70.1 ± 8.8 kg; mean age, 40 ± 8 years) were recruited for the study. Echocardiography was performed before the race, after the race, and 6 hours into recovery. RV and LV area and longitudinal ε were assessed using standard and speckle-tracking echocardiography. Following cubic spline interpolation, these variables were obtained across the same cardiac cycle and used to derive area-ε loops. RESULTS: The RV area-ε loop demonstrated a rightward shift after the race, with increased RV area (from 26.0 to 27.1 cm(2)) and reduced peak RV ε (from -28.6% to -25.8%). The recovery RV area-ε loop was similar to the postrace loop. A leftward shift was observed in the LV area-ε loop after the race, secondary to reduced LV area (from 35.8 to 32.5 cm(2)) and reduced peak ε (from -18.3% to -16.6%). In recovery, LV ε values returned toward baseline. CONCLUSIONS: A 100-mile ultramarathon resulted in a rightward shift in the RV area-ε loop as a result of RV dilatation. There was a concomitant leftward shift in the LV area-ε loop as a result of underfilling of the left ventricle. At 6 hours after exercise, there was a partial recovery of the left ventricle, while RV function remained depressed. It appears that changes in RV function do not have a serial impact on the left ventricle during recovery from ultra-endurance activity

Electrocardiogram reference intervals for clinically normal wild- born chimpanzees (Pan troglodytes)

OBJECTIVE To generate reference intervals for ECG variables in clinically normal chimpanzees (Pan troglodytes). ANIMALS 100 clinically normal (51 young [< 10 years old] and 49 adult [≥ 10 years old]) wild-born chimpanzees. PROCEDURES Electrocardiograms collected between 2009 and 2013 at the Tchimpounga Chimpanzee Rehabilitation Centre were assessed to determine heart rate, PR interval, QRS duration, QT interval, QRS axis, P axis, and T axis. Electrocardiographic characteristics for left ventricular hypertrophy (LVH) and morphology of the ST segment, T wave, and QRS complex were identified. Reference intervals for young and old animals were calculated as mean ± 1.96•SD for normally distributed data and as 5th to 95th percentiles for data not normally distributed. Differences between age groups were assessed by use of unpaired Student t tests. RESULTS Reference intervals were generated for young and adult wild-born chimpanzees. Most animals had sinus rhythm with small or normal P wave morphology; 24 of 51 (47%) young chimpanzees and 30 of 49 (61%) adult chimpanzees had evidence of LVH as determined on the basis of criteria for humans. CONCLUSIONS AND CLINICAL RELEVANCE Cardiac disease has been implicated as the major cause of death in captive chimpanzees. Species-specific ECG reference intervals for chimpanzees may aid in the diagnosis and treatment of animals with, or at risk of developing, heart disease. Chimpanzees with ECG characteristics outside of these intervals should be considered for follow-up assessment and regular cardiac monitoring