Assessment of myocardial deformation with CMR: a comparison with ultrasound speckle tracking in a cohort of highly trained endurance athletes

Funding Acknowledgements

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Plan Nacional I.D., Del Programa Estatal de Fomento De La Investigación Científica y Técnica de Excelencia, Subprograma De Generación Del Conocimiento, Ministerio de Economía y Competitividad 2013.

Background

 Myocardial deformation integrated with cardiac dimensions provides a comprehensive assessment of the ventricular remodelling patterns induced by cumulative effects of intensive exercise. Feature tracking(FT) can measure myocardial deformation from cardiac magnetic resonance(CMR) cine sequences; however, its accuracy is still scarcely validated.

Purpose

 Our aim was to compare FT’s accuracy and reproducibility to speckle tracking echocardiography (STE) in highly trained endurance athletes (EAs).

Methods

 93 EAs (>12 hours training/week during the last 5 years, 52% male, 35 ± 5.1 years) and 72 age-matched controls underwent a resting CMR and a transthoracic echocardiography to assess biventricular exercise-induced remodelling and biventricular global longitudinal strain (GLS) by CMR-FT and STE.

Results

  High endurance training load was associated with larger bi-ventricular and bi-atrial sizes and mildly reduced systolic function of both ventricles (p < 0,05). Strain values (both by CMR-FT and STE) proportionally decreased with increasing ventricular volumes potentially depicting the increased volume and functional biventricular reserve that characterize EAs heart. Strain values were lower when assessed by CMR-FT as compared to STE (p < 0.001), with good reproducibility for the LV (bias = 3.94%, LOA= ± 4.27%) but wider variability for RV strains (Figure 2).

Conclusions

  Biventricular longitudinal strain values were lower when assessed by FT compared to STE. Both methods were comparable when measuring LV strain but not RV strain. These differences might be justified by FT’s lower in-plane spatial and temporal resolution, which is particularly relevant for the complex anatomy of the RV.

Abstract Figure. Fig 1. Bland-Altman plots; FT vs STE.

Prevalence and pattern of cardiovascular magnetic resonance late gadolinium enhancement in highly trained endurance athletes

BACKGROUND

Intensive endurance exercise may induce a broad spectrum of right ventricular (RV) adaptation/remodelling patterns. Late gadolinium enhancement (LGE) has also been described in cardiovascular magnetic resonance (CMR) of some endurance athletes and its clinical meaning remains controversial. Our aim was to characterize the features of contrast CMR and the observed patterns of the LGE distribution in a cohort of highly trained endurance athletes.

METHODS

Ninety-three highly trained endurance athletes (> 12 h training/week at least during the last 5 years; 36 ± 6 years old; 53% male) and 72 age and gender-matched controls underwent a resting contrast CMR. In a subgroup of 28 athletes, T1 mapping was also performed.

RESULTS

High endurance training load was associated with larger bi-ventricular and bi-atrial sizes and a slight reduction of biventricular ejection fraction, as compared to controls in both genders (p < 0.05). Focal LGE was significantly more prevalent in athletes than in healthy subjects (37.6% vs 2.8%; p < 0.001), with a typical pattern in the RV insertion points. In T1 mapping, those athletes who had focal LGE had higher extracellular volume (ECV) at the remote myocardium than those without (27 ± 2.2% vs 25.2 ± 2.1%; p < 0.05).

CONCLUSIONS

Highly trained endurance athletes showed a ten-fold increase in the prevalence of focal LGE as compared to control subjects, always confined to the hinge points. Additionally, those athletes with focal LGE demonstrated globally higher myocardial ECV values. This matrix remodelling and potential presence of myocardial fibrosis may be another feature of the athlete's heart, of which the clinical and prognostic significance remains to be determined.

Three-dimensional regional bi-ventricular shape remodeling is associated with exercise capacity in endurance athletes

AIMS

Endurance athletes develop cardiac remodeling to cope with increased cardiac output during exercise. This remodeling is both anatomical and functional and shows large interindividual variability. In this study, we quantify local geometric ventricular remodeling related to long-standing endurance training and assess its relationship with cardiovascular performance during exercise.

METHODS

We extracted 3D models of the biventricular shape from end-diastolic cine magnetic resonance images acquired from a cohort of 89 triathlon athletes and 77 healthy sedentary subjects. Additionally, the athletes underwent cardio-pulmonary exercise testing, together with an echocardiographic study at baseline and few minutes after maximal exercise. We used statistical shape analysis to identify regional bi-ventricular shape differences between athletes and non-athletes.

RESULTS

The ventricular shape was significantly different between athletes and controls (p < 1e-6). The observed regional remodeling in the right heart was mainly a shift of the right ventricle (RV) volume distribution towards the right ventricular infundibulum, increasing the overall right ventricular volume. In the left heart, there was an increment of left ventricular mass and a dilation of the left ventricle. Within athletes, the amount of such remodeling was independently associated to higher peak oxygen pulse (p < 0.001) and weakly with greater post-exercise RV free wall longitudinal strain (p = 0.03).

CONCLUSIONS

We were able to identify specific bi-ventricular regional remodeling induced by long-lasting endurance training. The amount of remodeling was associated with better cardiopulmonary performance during an exercise test.