Redefining cardiomyopathies: the role of cardiovascular magnetic resonance imaging.

With great interest I read the article 'Reduced right ventricular ejection fraction in endurance athletes presenting with ven-tricular arrhythmias: a quantitative angio-graphic assessment' by Ector et al. 1 Even if invasive methods are employed, a thorough evaluation of the morphology and functions of the right ventricle (RV) may be difficult due to the complex geometry and anatomy. Examination of RV geometry in athletes poses an additional puzzle because of the gross changes of both ventricular shape and function associated with athletic training. 2 Based on the current literature, the RV plays two major roles in cardiovascular function and prognosis: both good and bad. In its deleterious role, dysfunction and pathologies of the RV lead to series cardiac arrhythmias and a poor prognosis. 3 Studies have shown that the patient's degree of ven-tricular geometric distortion correlates with RV or left ventricle (LV) pressure and volume overload, which often affects each other. 4 It has also been shown that primary RV systolic dysfunction can lead to secondary changes in the systolic and diastolic function of the LV. 4 Although the authors of this study presented ventricular arrhythmias and RV dysfunction, the authors did not test the effects of LV functions on RV functions by multivariate analysis. RV changes without evaluating any real time LV alterations this may lead to difficulties. Biffi et al. 5 found that a reduction in the frequency of ventricular tachyarrhyth-mias after deconditioning and the absence of cardiac events in follow-up support the benign clinical nature of these rhythm disturbances as just another expression of ath-lete's heart. But an important question that has not been asked is what prognostic role could ventricular arrhythmias play in athletes without cardiovascular abnormalities? In its beneficial role, a better functional RV in the maintenance of endurance capacity and its function may contribute to enhanced endurance capacity via increased LV filling and performance. 6 Both the pulmonary and the systemic circulation must show a performance change to meet a circulatory demand of extensive and prolonged physical exercise. 6 Both the RV and the LV must alter its performance to meet the increased circulatory demands of exercise. RV adaptation to intense and prolonged physical exercise may be expected to increase the RV cavity dimensions, with a concomitant increase in RV contractile reserve. 6,7 Interestingly, RV cavity diameters in endurance-training athletes were higher than in strength – this phrase/sentence also needs a numerical reference training athletes. …