Left ventricular hypertrophy in middle-aged endurance athletes

Both regular physical activity and hypertension may be related to increased myocardial thickness, but the interplay between these two factors in causing cardiac remodeling in athletes is still a matter of debate. The aim of this study was to analyze the relation between resting and peak exercise blood pressure (BP) and myocardial hypertrophy in healthy middle-aged amateur endurance athletes. The study included 30 male, long-term athletes (mean age 40.9±6.6 years) who underwent resting BP assessment, cardiopulmonary exercise testing with peak exercise BP measurement, and cardiac magnetic resonance. We found that interventricular septal diameter is increased in athletes with high-normal resting BP (n=11, 37%) – median 13 mm (interquartile range: 12–13.75 mm), but not in those with optimal or normal BP (n=19) – median 10 mm (10–11.75 mm), P=0.001. This finding is accompanied by significantly higher left and right ventricular mass index and larger left atrial area in the first group. These differences are even more pronounced in athletes in whom high-normal BP is accompanied by exaggerated blood pressure response (EBPR) to exercise, whereas isolated EBPR to exercise does not lead to hypertrophy or further left atrial enlargement. Prehypertension, isolated or combined with EBPR to exercise, affects cardiac remodeling in athletes. Identification of increased myocardial thickness in pure endurance middle-aged athletes should merit further investigation on masked hypertension.