Echocardiographic criteria of physiological left ventricular hypertrophy in combined strength- and endurance-trained athletes

In combined strength- and endurance-trained athletes who are showing both unusual large body dimensions as well as a high physical fitness, the dimensions of the athlete's heart are expected to reach physiological limits. Therefore we investigated 75 male and 77 female competitive rowers by means of doppler-echocardiography. The absolute "critical" heart weight of 500 g was exceeded by 61%' of the male and 10%' of the female rowers. Maximal values of the left ventricular (LV) muscle mass were measured at 170 (men) and 133 (women) g.m-2 body surface area, respectively. The LV end-diastolic internal diameter was measured to be above the upper clinical limit of 55 mm in 55%' of the male and 17%' of the female rowers. A LV wall thickness of 13 and 12 mm was only exceeded by 3 male and 1 female athlete, respectively (maximal values: 14 and 12.5 mm). The LV wall/internal diameter ratio did not exceed 48-50%'. The systolic LV function as well as ECG and blood pressure did not reveal any pathological finding, the diastolic LV function was always measured within the normal range. The LV wall thicknesses, internal diameter and hypertrophic index (relation between wall thickness and internal diameter) of the rowers were significantly higher than those of 62 non-endurance trained athletes (pairwise matched according to the body dimensions) and similar to 28 male pure endurance athletes (pairwise matched according to the absolute heart volume).In conclusion, upper limits of echocardiographic volume measurements that are considered critical may be clearly exceeded by healthy strength-endurance trained athletes with simultaneously high body dimensions. The clinical limits, however, are still valid in subjects with a body mass up to approximately 70 kg. The LV wall thickness only exceptionally exceed the clinical limits. A specific influence of the strength elements in training on the LV hypertrophy had not be found.     

Physiological or pseudophysiological ECG changes in endurance-trained athletes

"Sudden cardiac death" in seemingly healthy, active, and asymptomatic people has always been a tragic fact and is now occurring more frequently. Thus, the preventive detection of "subjects at risk" becomes a priority. A traditional resting electrocardiogram can sometimes give useful indications. Fifty-two competitive triathletes were compared with 22 control persons with similar anthropometric parameters. All subjects underwent the same noninvasive cardiac exploration with electrocardiography, bidimensional echo-Doppler examination, and maximal spiro-ergometric exercise tests, on a stationary bicycle as well as on a treadmill. In the triathletes we noted manifest signs of eccentric as well as concentric left ventricular hypertrophy with arguments for a supernormal diastolic left ventricular function, with important hemodynamic adjustments and with consequences on the resting electrocardiogram. We described "ten commandments" in evaluating the resting electrocardiogram of healthy competitive athletes. We suspect that the occurrence of ventricular premature beats at peak load of a maximal exercise could be the first expression of a pathological cardiac adaptation to sports activities. The resting electrocardiogram can show interesting details in detecting the "subjects at risk" for problems such as possible lethal arrhythmias and "sudden cardiac death." The analysis of the four subgroups of triathletes compels us to feel dubious about the "athletic heart syndrome" as a physiological entity. In several cases the "athletic heart" is possibly a transitional situation to a pathological hypertrophic and dilated cardiomyopathy. Received: July 3, 2000 / Accepted: February 9, 2001     

Importance of determining the percentage body fat in endurance-trained athletes

A triathlete has to complete a hard endurance effort in aerobic circumstances. This requires important cardiovascular, haemodynamic and metabolic adaptations which alter the percentage body fat. This study included 52 triathletes and 22 control persons. The anthropometric data of the two groups were similar. All the subjects underwent the same extensive non-invasive cardiac exploration with two-dimensional cardiac echo-doppler examination. Maximal incremental exercise tests with determination of lactate and the ventilatory threshold were done on bicycle and on treadmill. Three different methods determined the percentage of body fat: 4 and 12 skin fold method, bioelectrical impedance analysis and dual energy X-ray absorptionmetry. The results showed important structural and functional heart changes in the triathletes. These changes caused distinct heamodynamic adaptations so that the maximal performing capacity and the aerobic capacity could be forced up largely. The haemodynamic adaptations were connected with changes in the percentage body fat in triathletes. The determination of the 12 skin fold measurements enabled us to distinguish the triathletes with better competition results from the inferior triathletes. It is concluded that the method of 12 skin fold measurements gives the most reliable results and requires only a limited instrumentarium. Moreover, this examination can be performed correctly and easily in all circumstances.     

Mental stress response,arterial stiffness,and baroreflex sensitivity in healthy aging

This study examined the relationship of pressor responses during mental stress to arterial stiffness and baroreflex sensitivity. Hemodynamic responses of 24 healthy individuals (51-86 years old) to two mental stress tasks (math and speech) were compared with common carotid artery mechanical stiffness and autonomic nervous system regulation of blood pressure as measured by using the modified Oxford technique. At the ages studied, no effect of age on stress task responsiveness, carotid stiffness, or baroreflex sensitivity was observed. Carotid stiffness and baroreflex sensitivity demonstrated a strong inverse relation. Change in heart rate during the speech task was correlated with arterial stiffness, and the increase in mean arterial pressure was associated with carotid stiffness and was inversely correlated to baroreflex sensitivity. These associations suggest that acute hemodynamic reactions to mental stress among healthy adults are determined, in part, by structural properties of arterial vessels and sensitivity of arterial baroreflex. These observations may provide a mechanistic link between the physiology of cardiovascular reactivity to stress and risk of cardiovascular events in middle-aged and older individuals.     

Assessment of arterial stiffness, oxidative stress and inflammation in acute kidney injury

Background

It is well know that arterial stiffness, oxidative stress and inflammation are features of chronic kidney disease. The arterial changes have a multitude of potential interconnected causes including endothelial dysfunction, oxidative stress, inflammation, atherosclerosis and vascular calcification. There is evidence that arterial stiffness becomes progressively worse as CKD progresses. The contribution of the biochemical changes of uremic toxicity to arterial stiffness is less clear. The aim of this study is to elucidate the vascular changes in acute kidney injury. We hypothesise that arterial stiffness will be increased during acute kidney injury and this will return to normal after kidney function recovers.

Methods/Design

One hundred and forty four patients with acute kidney injury defined as an acute increase in serum creatinine to > 133 μmol/l or urea > 14.3 mmol/l or urine output < 410 ml/day will be recruited. Baseline measures of aortic pulse wave velocity, augmentation index, and brachial and central blood pressure will be recorded along with blood measures for oxidative stress and inflammation. Repeat measures will be taken at six and 12 months after the onset of the acute kidney injury.

Discussion

The role and contribution of the biochemical changes to arterial stiffness in the acute phase of kidney disease is not known. This study will primarily assess the time course changes in pulse wave velocity from the onset of acute kidney injury and after recovery. In addition it will assess augmentation index, central blood pressure and oxidative stress and inflammation. This may shed light on the contribution of biochemical kidney toxins on arterial stiffness in both acute kidney injury and chronic kidney disease.

Trial Registration

ACTRN 12609000285257     

Left ventricular response to submaximal exercise in endurance-trained athletes and sedentary adults.

This investigation examines the hypothesis that athletes increase stroke volume with submaximal exercise through an augmentation of left ventricular (LV) end-diastolic volume and a reduction of LV end-systolic volume, whereas sedentary adults only increase stroke volume modestly, because LV end-diastolic volume does not increase. Upright bicycle exercise was performed by 17 endurance-trained male athletes and 15 sedentary men. M-mode echocardiograms were obtained during submaximal exercise at predetermined heart rates. Athletes, at a heart rate of 130 beats/min, increased their stroke volume 67% from 72 +/- 18 ml to 120 +/- 26 ml (p less than 0.001). This resulted from an increase of LV end-diastolic volume from 119 +/- 23 to 152 +/- 28 ml (p less than 0.001) and a reduction in LV end-systolic volume from 46 +/- 14 to 31 +/- 9 ml (p less than 0.001). Sedentary men at the same heart rate increased stroke volume 22% from 63 +/- 15 to 77 +/- 21 ml (p less than 0.05). LV end-diastolic volume did not change (96 +/- 20 vs 97 +/- 28 ml) (p = not significant), but LV end-systolic volume decreased (33 +/- 11 vs 20 +/- 9 ml) (p less than 0.001). In conclusion, athletes increased cardiac output through a more prominent augmentation of stroke volume than sedentary subjects at submaximal exercise. This was accomplished through an augmentation of LV end-diastolic volume. This may have a conserving effect on myocardial oxygen consumption at these levels of exercise.     

心脏重塑与动脉弹性

心脏与血管组成人体的血液循环系统。心脏是维持血液循环的动力器官,起到血液泵的作用,而动脉系统的功能是将心脏射出的血液输送至全身。动脉弹性下降致外周阻力增高,心脏所受的机械负荷增加,出现心脏重塑。另一方面,心排血量的改变和神经体液调节的改变也可导致动脉弹性的变化。所以,心脏重塑和动脉弹性成为现代心血管方面研究的两个热点。本文旨在对这方面研究作一综述。1心脏重塑早在1979年,Ferrario等人就提出了心肌重塑概念(my-ocardial remodeling),即心肌结构发生改变,心肌重塑对维持正常心功能有利。Lbtan[1]认为,心肌肥大是心脏重…     

Alcohol consumption and arterial stiffness in men

OBJECTIVE: Moderate alcohol consumption has been proposed to be anti-atherogenic and protect against coronary heart disease. Arterial stiffness provides a summary measure of atherosclerotic arterial damage and cardiovascular risk. A vascular protective effect of moderate alcohol consumption would be reflected in an inverse association between alcohol intake and aortic stiffness. DESIGN: A cross-sectional study. SETTING: The male population of Utrecht. PARTICIPANTS: Of 370 men, aged 40-80 years, alcohol intake was calculated from a standardized questionnaire and aortic stiffness was non-invasively assessed by pulse-wave velocity (PWV) measurement of the aorta. RESULTS: There were no non-drinkers; therefore the group consuming 0-3 glasses of alcoholic beverage per week was chosen as the reference group in the analyses. Those drinking 4-10, 11-21 and 22-58 glasses of alcoholic beverage per week had a -0.77 m/s (95% confidence interval, -1.26 to -0.28), -0.57 m/s (95% confidence interval, -1.07 to -0.08) and -0.14 m/s (95% confidence interval, -0.65 to 0.36) difference in mean PWV compared with those drinking 0-3 glasses per week. Adjustment for factors that correlated with PWV or alcohol consumption did not change the strength of the association. CONCLUSION: Among men aged 40-80 years there is a J-shaped association between alcohol consumption and PWV. This further supports a decreased risk of cardiovascular disease with moderate alcohol consumption.     

Effects of aging on cardiorespiratory responses to brief and intense intermittent exercise in endurance-trained athletes

The aim of this study was to investigate the effects of aging on athletes' cardiorespiratory responses to a brief intense intermittent effort, using the force-velocity test as an exercise model. Twelve young athletes (24.8 +/- 1.3 years) and twelve master athletes (65.1 +/- 1.2 years) with similar heights, body masses, and endurance training schedules participated in this study. They performed both a maximal graded exercise and the force-velocity tests. The force-velocity test consisted of the repetition of 6-second sprints against increasing braking forces with 5-minute recovery periods. None of the subjects presented abnormal electrocardiogram responses to the tests. During the force-velocity test, the heart rate magnitudes of response in all subjects were correlated to the corresponding sprint power output (p < .001), with higher values for the young athletes (p < .001). Both groups had similar systolic blood pressure peaks of response during the force-velocity test. Both groups had similar preexercise and end-of-recovery oxygen consumption (VO2), but the young athletes had higher peaks of response (p < .001). The VO2 magnitudes of response increased during the test (p < .01) in all subjects, with higher values for the young athletes (p < .001). There was a positive correlation between the VO2 magnitude of response and (1) the corresponding sprint power output (R = .58,p < .001) and (2) the corresponding number of sprint repetitions (R = .29, p < .02). The young athletes had higher end-of-recovery and peak carbon dioxide production (VCO2) responses than the master athletes (p < .001). Pulmonary ventilation (V(E)) peaks of response to the sprints were higher in the young athletes (p < .001). There was a positive relation between the V(E) and VCO2 peaks of response (R = 84,p < .001). In both groups the peak heart rate, VO2, VCO2, and V(E) values attained during the force-velocity test represented similar percentages of the maximal values reached at exhaustion of maximal graded exercise. These results showed that aging does not alter the percentage of the cardiorespiratory response to a brief intense intermittent exercise such as the force-velocity test. Moreover, the arterial blood pressure response is not significantly altered, whereas the vasodilatatory response is.