Influência da hereditariedade para hipertensão arterial na hipotensão pós-exercício físico

Abstract

Introduction: In normotensive individuals, a positive family history of arterial hypertension leads to a greater chance of developing hypertensive disease. The relative risk of developing hypertension being 1.5 and 1.8 when only the mother or father is hypertensive, respectively. This increased risk can be justified, at least in part, by the cardiovascular damage of these individuals, both at rest and during physical exercise. On the other hand, in the general population, positive cardiovascular changes are observed in the recovery period after physical exercise, such as post-exercise hypotension. However, the effect of stratification of family history between mother and father on these cardiovascular changes after physical exercise is not known. Objective: To verify the cardiovascular behavior of normotensive men with a positive family history of hypertension from the mother and normotensive men with a positive family history of hypertension from the father after an aerobic exercise session. Method: A randomized clinical trial was conducted with a sample of 35 men, aged between 18 and 40 years, sedentary, normotensive, non-obese, absent from cardiovascular and pulmonary disease, divided into the following groups: HFm group (participant having a mother with arterial hypertension , n = 14) and HFp Group (participant having a father with arterial hypertension, n = 21). The participants were submitted to aerobic physical exercise, on a cycle ergometer (Kikos®), for 50 minutes, at an intensity of 50 to 70% of the reserve heart rate (exercise session). And, also, the control session characterized by the same time, but without physical exercise (control session). The sessions were held randomly. The variables blood pressure, heart rate (FinometerPro® / Biopac®) and blood flow in the forearm (Venous Occlusion Plethysmography - Hokanson®) were evaluated and recorded continuously for 10 minutes before and after 30 minutes of each session. The peripheral vascular resistance of the forearm was calculated by dividing the mean arterial pressure by the blood flow in the forearm. Two-factor analysis for repeated measures was performed to test possible differences between exercise and control sessions, within the same group. P≤0.05 was considered to be a significant difference. Results: In the HFm group, systolic blood pressure, diastolic blood pressure, mean arterial pressure, heart rate and peripheral vascular resistance of the forearm did not change significantly in the post-moment compared to the pre-exercise moment. However, systolic blood pressure, diastolic blood pressure, mean arterial pressure and peripheral vascular resistance of the forearm increased significantly and the heart rate significantly decreased in the post-moment compared to the pre-control moment. Differently, in the HFp group, systolic blood pressure, mean arterial pressure, and peripheral vascular resistance of the forearm significantly reduced in the post-moment compared to the preexercise moment. Heart rate increased significantly and diastolic blood pressure was similar between the post and pre-exercise sessions. In the control session, systolic blood pressure, diastolic blood pressure, mean arterial pressure and peripheral vascular resistance of the forearm increased significantly and the heart rate significantly decreased in the post-hour compared to the pre-time. Conclusion: Physical exercise did not cause significant changes in the cardiovascular system of normotensive men, with a positive family history of hypertension from the mother, while those with a positive family history of hypertension from the father had post-exercise hypotension. This hypotensive response was partially justified by the decrease in peripheral vascular resistance of the forearm.