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................................................................................................. 5.3.5.1 Mitral valve prolapse Mitral valve prolapse (MVP) is characterized by fibro-myxomatous changes of the mitral valve leaflets and has a prevalence of 12.4%.328,329 The diagnosis of MVP is defined as >2 mm displacement of one or both leaflets of the mitral valve beyond the annulus within the left atrium in end-systole.330 MVP is generally benign with a 10-year mortality risk of 5%.331 The majority of individuals are identified incidentally during cardiac auscultation, or echocardiography.

The most common complication of MVP is the progression to chronic severe MR, in 510% of individuals with MVP. Other complications include HF from chronic MR, pulmonary hypertension, infective endocarditis, supraventricular and VAs, and, occasionally, SCD.313 In the Italian cardiac pathology registry of 650 SCDs in young adults, 7% were attributed to MVP.332 Most decedents showed scarring in the infero-basal wall and papillary muscles and bi-leaflet prolapse. Myocardial scarring, mitral valve annular disjunction (i.e. an abnormal atrial displacement of the mitral valve leaflet hinge point during systole),333 T-wave inversion in the inferior leads and VAs arising from the LV [right bundle branch block (RBBB) morphology] were high-risk features for SCD.334 The mechanical strain of MVP on papillary muscles and adjacent myocardium is thought to be responsible for the myocardial scarring, which may be a possible mechanism for life-threatening arrhythmias in some individuals.335,336 In general, exercising individuals with MVP have an excellent prognosis. In a recent Italian study of 7449 young competitive athletes, MVP was identified in 2.9%. During a follow-up period of 8 ± 2 years there were no fatalities.337 Adverse events, including progressive MR with LV dilatation, ischaemic stroke, and AF occurred at a rate of 0.5% per annum and were more common in older athletes with baseline mitral valve disjunction or VAs. Individuals with MVP should be evaluated with an exercise test and 24-hour ECG. Individuals with inferior T-wave inversion or ventricular premature beats arising from the LV should undergo a CMR imaging scan to check specifically for myocardial fibrosis affecting the infero-basal wall. Other potentially high-risk markers include evidence of mechanical dispersion detected by speckled tracking echocardiography,338 coexisting prolongation of the QT interval and mitral annular disjunction.333

Given the relatively benign nature of MVP, asymptomatic patients with mild or moderate MR can participate in all competitive sports and leisure sports in the absence of the aforementioned risk factors (Figure 8). Asymptomatic patients with severe MR but none of the above high-risk markers may compete in low- to moderate-intensity sports after detailed discussion with their specialist in the presence of LV end-diastolic diameter (LVEDD) <60 mm (or <35.5 mm/m2 in men and <40 mm/m2 in women) with LVEF >_ 60%, resting sPAP < 50 mmHg, and normal exercise test. Symptomatic patients with MVP and any of the aforementioned high-risk features (Figure 8) should not participate in recreational or competitive sports; however, low-intensity aerobic exercise should be encouraged to improve functional capacity and general well-being.

5.3.6 Mitral stenosis Although rheumatic valve disease is uncommon in the western world, the increase in emigration patterns means that cardiologists may encounter individuals with rheumatic mitral stenosis (MS) who aspire to exercise. Individuals with advanced MS are usually symptomatic and incapable of engaging in exercise regimens with a high CV demand. The risk stratification of exercising individuals with MS is based largely on a detailed echocardiogram with specific interest in the severity of the lesion and accompanying systolic PAP. In addition, assessment should include a maximal exercise stress test to identify concealed symptoms and functional capacity.

Figure 8 Specific markers of increased risk of sudden cardiac death (SCD) with mitral valve prolapse. LV = left ventricular; MR = mitral regurgitation; MV = mitral valve. Adapted from Gati et al.336 Downloaded from academic.oup.com/eurheartj/article/42/1/17/5898937 by guest on 07 October 2026