ABC | Volume 115, Nº1, July 2020

Viewpoint Appropriate Use of Diastolic Function Guideline When Evaluating Athletes: It is not Always what it Seems to Be Carlos Eduardo Suaide Silva 1 Diagnósticos da América SA – Cardiologia, 1 São Paulo, SP - Brazil The complete echocardiographic evaluation of the diastolic function has always been a great challenge for cardiologists and sonographers, either because of frequent changes found in every new guideline, due to a great amount of recent information about this complex subject, or because of some confusion created by the guidelines themselves, which are many times contradictory or not explanatory. 1 However, we are moving towards a better understanding of what really happens on this important phase of the cardiac cycle. The last published guideline of 2016, despite presenting some inconsistencies and still not making certain situations clear, clarified several points and corrected some distortions of the previous one. 2 As usual in Medicine, every time we have a paradigm shift or a new clinical entity appears, we pass first through a moment of overdiagnosis followed by some discredit to finally reach a balance with the maturity and the knowledge acquired over time. The same happened with mitral valve prolapse, which showed an incidence of more than 30% in young women in the early 1970s, but nowadays it is known of about 2.5% in both sexes. 3 Ventricular non-compaction and many other diseases followed the same pattern, as well as diastolic disfunction. How many healthy elderly people were diagnosed with mild diastolic disfunction (or grade I) due to presence of E/A inversion on spectral Doppler of the mitral inflow? Almeida et al. 4 tested the impact of using the 2009 guidelines against 2016 for diagnosing diastolic disfunction in 1,000 elderly individuals (over 45 y/o). They found that only 1.4% had some degree of diastolic disfunction according to the 2016 guideline. On the other hand, if the 2009 guideline had been used, this number would rise to 38.2%. Thus, with this new guideline, we seem to have come to this balance and by using the correct application of its criteria we can significantly reduce the excessive diagnosis of diastolic disfunction, mainly in the elderly. However, we may still fail to diagnose, fortunately in a much lower amount of cases, in another clinical situations. Particularly in athletes, diastolic function needs to be evaluated more carefully. Exercise is a strong stimulus for muscle adaptation, and there is plenty of evidence proving that it is responsible for changes in shape and cardiac output. 5 The adaptations imposed to the heart depend, of course, on the type of performed exercise. Therefore, didactically, athletes that perform dynamic exercises and work out at a high heart rate, such as marathon runners or swimmers, suffer different adaptations from those who perform isometric (static) exercises, in which the heart rate is lower and there is predominant increase in blood pressure as it happens with bodybuilders. In practice, most exercises are mixed as in cyclists and rowers, for example. In the first group (marathon runners), in which the cardiac output can reach ten times the resting value, the heart needs to adapt in a variety of manners, whether starting from a very low basal heart rate (bradycardia), increasing left ventricular volume (eccentric hypertrophy) or even making its pump more effective, by extracting the maximum of its diastolic and systolic functions. The diastole of these athletes must be extremely efficient because tachycardia shortens this phase and the heart has much less time to be filled. Thus, as soon as the mitral valve opens, the left ventricle must fill up quickly, show an extremely effective relaxation and “suck” as much blood as possible to generate an effective systole. It explains the big E wave on mitral Doppler followed by a small A wave (because there is little blood left to fill the ventricle on the end of diastole), thus showing a flow pattern similar to restrictive, but reflecting, in fact, a supernormal diastole 6 (Figure 1). In the second group (bodybuilders), in which the heart is subjected to high pressures without increasing its frequency too much, we can find predominant increase in wall thickness without dilatation (concentric hypertrophy, augmented muscle stiffness, and longer relaxation period leading to a prolonged deceleration time of mitral E wave and an inverted E/A ratio). These situations are exaggerations, and the examples used herein are only for better understanding, but in the real world, diastolic evaluation in athletes is usually much more complex. We will show, with two clinical examples, how the rational use of the new guideline along with advanced echocardiographic techniques and clinical history can lead to a correct and refined analysis of diastolic function on this population. Example 1: 16-year-old male soccer player (same patient of Figure 1). If we look only for the mitral flow pattern of this athlete, we will find an E/A ratio of 2.25 and an E wave deceleration time of 138 ms, which could resemble a restrictive pattern that is incompatible with the status of a young athlete. Tissue Doppler velocity shows septal e’ of 0.17 m/s and lateral e’ of 0.18 m/s. It leads to an E/e’ ratio of 7.01. Tricuspid regurgitation velocity was 1.33 m/s and there was left atrium volume indexed of 27.9 mL/m 2 (Figure 2). All measurements Mailing Address: Carlos Eduardo Suaide Silva • Av. Juruá, 434. Postal Code 06455-010, Barueri , SP – Brazil E-mail: csuaide@cardiol.br Manuscript received October 04, 2018, revised manuscript December 03, 2019, accepted December 27, 2019 Keywords Ventricular Dysfunction; diagnostic Imaging; Echocardiography/methods; Guidelines as Topic; Sports; Exercise; Athletes. DOI: https://doi.org/10.36660/abc.20190689 134