Association of lifelong exercise characteristics with aortic pathology in patients with Marfan syndrome

Abstract

Abstract Background Marfan syndrome (MFS) is a genetic connective tissue disease with an increased risk for aortic root dilatation and aortic dissection. Current guidelines, based on expert consensus, recommend exercise restrictions due to concerns that exercise-induced hemodynamic stress may accelerate aortopathy. Studies examining exercise characteristics and their association with aortopathy in MFS patients are lacking. Purpose To assess the association of lifelong exercise characteristics (volume, intensity and type) with the presence of aortic dilatation in MFS patients. Methods An international multi-centre study was conducted in MFS adults. Patients were classified as sedentary (<500 metabolic equivalent of task minutes per week [MET-min/wk]), active (500-1000 MET-min/wk), or highly active (≥1000 MET-min/wk) based on lifelong exercise volumes assessed by a validated questionnaire. Patient’s dominant exercise intensity was classified as moderate (3-6 MET) or vigorous (≥6 MET), and sport type as skill, power, mixed, or endurance. Echocardiography was used to assess diameters at the sinuses of Valsalva (SoV) and ascending aorta (AA), and Campens Z-scores were calculated. Aortic dilatation was evaluated as a diameter ≥40, ≥45 mm, a Z-score ≥2 or ≥3 respectively. Results 315 patients (36[27-49] years, 53% male) were included of which 104 were sedentary, 77 active and 134 highly active (Fig. 1). 42 patients did not perform sport-related exercise, whereas 147 and 121 patients predominantly participated in moderate or vigorous intensity sports. Patients performing sports were allocated to the skill (n=13), power (n=27), mixed (n=158), endurance (n=66) or non-dominant (n=9) exercise type group. Mean SoV and AA diameters were 42.9±7.7 mm and 33.9±7.3 mm. SoV or AA diameters of ≥40 mm were present in 200 (64%) and 41 (13%) patients, whereas 223 (71%) and 81 (26%) patients had a Z-score ≥2 for the SoV or AA. Exercise volume was not associated with SoV dilatation (Fig. 2). Moderate and vigorous intensity sports were associated with a lower prevalence of SoV Z-score ≥3. Power sport was associated with a lower prevalence of all definitions of SoV dilatation, whereas mixed and endurance sports were associated with a lower prevalence of SoV Z-score ≥3. No associations were found with AA dilatation. Of the 17 (5%) patients who suffered from an aortic dissection, 1 case occurred during walking (type A dissection) whereas all other cases were not exercise-related. Conclusions Lifelong exercise volumes were not associated with aortic dilatation in MFS patients. Power sports and vigorous intensity exercise were inversely related to SoV dilatation. Further investigation is warranted to clarify whether this association reflects that patients engaging in these activities have a less severe cardiovascular phenotype, or that they are protected from exercise-related aortic complications, and if patients may miss health benefits due to too exercise restrictions.