1,720,966 research outputs found
Responses to Tilt test in young and elderly patients with syncope of unknown origin
No full textThe aim of the present study was to assess the cardiovascular autonomic function and responses to tilt test in young and elderly patients with syncope of unknown origin. We evaluated two groups of patients with previous unexplained syncope: 192 older subjects (112 males, 80 females, mean age 67.2 +/- 6.8 years) and 188 young subjects (102 males, 86 females, mean age 25 +/- 9 years). All patients underwent ambulatory electrocardiogram (ECG) monitoring, to evaluate time domain indices of heart rate variability (HRV), and head-up tilt test in the morning after an overnight fast. The responses of positive tilt test were classified using the VAsovagal Syncope International Study (VASIS) criteria: mixed (VASIS-1), cardioinhibition (VASIS-2A), severe cardioinhibition/asystole (VASIS-2B), pure vasodepression (VASIS-3). All the time-domain HRV indexes were lower in the older than in young subjects. The rate of positive responses was not different in the two groups. In elderly group the positive head-up tilt test responses showed: a pure vasodepressive response (VASIS 3) in 126 patients (65%), a mixed (VASIS-1) response in 25 patients (13%), a cardioinhibitory (VASIS-2A) response in 13 patients (7%). Only 28 (14.6%) of elderly group patients had negative head-up tilt test response. In contrast, in young group the positive head-up tilt test responses showed: 114 patients (61.2%) a mixed (VASIS-1) vasovagal response, 40 patients (22.3%) a cardioinhibitory (VASIS-2A) response, four (2.1%) patients a severe cardioinhibitory (VASIS-2B) and four (2.1%) patients a pure vasodepression (VASIS-3) response, respectively. The tilt test was negative in response in 26 young patients (12.2%). Our results confirm that the head-up tilt test may be useful in assessing unexplained syncope, since it is seen to be positive in 85% of elderly patients and 86% in young patients. In our subjects, vasodepressive response was the most frequent cause of syncope in older subjects, while vasovagal response is the commonest cause of syncope of young patients. This different behaviour in the elderly may be is explained with physiological aging, which is associated with a reduction of sympathetic-parasympathetic control on the cardiac rhythm, demonstrated by reduction in all the time domain HRV indices
Effect of nebivolol on QT dispersion in hypertensive patients with left ventricular hypertrophy
No full textHypertensive patients with left ventricular hypertrophy (LVH) have increased QT dispersion, which is considered an early indicator of end-organ damage and a non-invasive marker of risk for clinically important ventricular arrhythmias and cardiac mortality. The purpose of this study was to examine the effect of nebivolol antihypertensive therapy on QT dispersion in hypertensive subjects. Twenty-five subjects (15 men and 10 women, mean age 53.6 +/- 4.5 years) with essential arterial hypertension and mild-to-moderate LVH (blood pressure: 147.2 +/- 6.2/90.6 +/- 3.8 mmHg; left ventricular mass indexed: 149.1 +/- 10.7 g/m(2)) were compared with 25 age-matched healthy control subjects. All the participants underwent a complete clinical examination, including electrocardiogram for QT interval measurements. The QT dispersion was defined as the difference between the longest and the shortest QT interval occurring in the 12-lead electrocardiogram. The QT dispersion was corrected (QTc) with Bazett's formula. Hypertensive subjects were treated with 5 mg daily of nebivolol. The ECG and echocardiogram were repeated after four weeks of treatment. At baseline, hypertensive patients showed QT dispersion (56.9 +/- 6.4 vs. 31.7 +/- 8.4 ms, P < 0.001) and QTc dispersion (58.3 +/- 6.2 vs. 33.2 +/- 7.8 ms, P < 0.001) significantly higher than control subjects. Four-week nebivolol treatment reduced blood pressure from 147.2 +/- 6.2/90.6 +/- 3.6 mmHg to 136.3 +/- 3.1/83.3 +/- 2.5 mmHg (P < 0.0001), and resting heart rate from 75.3 +/- 4.7 to 64.2 +/- 3.0 bpm (P < 0.001), without significant change in left ventricular mass (LVMi: 149.1 +/- 10.7 vs. 151.4 +/- 9.8 g/m(2), ns). Nebivolol-based treatment improved QT dispersion (56.9 +/- 6.4 vs. 40.5 +/- 5.8 ms, P < 0.001) and QTc dispersion (58.3 +/- 6.2 vs. 42.2 +/- 5.6 ms, P < 0.001), which remained higher than in control subjects (P < 0.001 in both cases). The reduction of QT dispersion did not correlate with arterial BP reduction. In conclusion, nebivolol reduced increased QT dispersion in hypertensive subjects after four weeks. This effect, occurred without any change in LVM, did not seem to be related to the blood pressure lowering and could contribute to reduce arrhythmias as well as sudden cardiac death in at-risk hypertensive patient
Ultrasonic backscatter of the carotid wall in young and older athletes
No full textObjectives. The aim of this study was to evaluate the effects of habitual exercise on the age-related changes of carotid wall composition defining its acoustic reflectivity by the quantitative approach of integrated backscatter (IBS) analysis. Desing. Cross-sectional study. Setting. University Hospital. Subjects. Fifty-four competitive long-distance runners (males, age range 22-72 years) and 50 healthy sedentary controls. Main outcome measures. All the subjects underwent both 2-D conventional ultrasonography and IBS analysis. IBS values were sampled from a region of interest (ROI) placed within five consecutive regions of the common carotid intima-media, and then corrected (C-IBS) for the IBS value of the adventitia. Results. Athletes showed a lower C-IBS (-27.07 +/- 2.9 dB vs. -24.57 +/- 4 dB, P 60 years of age) tertile of age, we assess the influence of age on IMT and IBS. Sedentary older individuals exhibited an IMT higher respect to young controls and to the both trained subgroups (P < 0.0001). C-IBS was lower in both subgroups of athletes, independently of age, and lower in sedentary young people respect to sedentary older subgroup (P < 0.0001). Endurance chronic exercise blunted the difference of C-IBS observed between young and older sedentary individuals. Moreover, C-IBS was positively related to age (r = 0.77, P < 0.0001) and IMT (r = 0.52, P < 0.0001). Conclusions. The age-related changes of the arterial wall are attenuated by physical training. These modifications can be quantitatively discriminated by ultrasonic backscatter method
QT dispersion in elderly athletes with left ventricular hypertrophy
No full textThe purpose of this study was to examine the QT dispersion in elderly endurance athletes with left ventricular (IV) hypertrophy. Sixteen athletes (males, mean age 67.6 +/- 4.5 years) with mild to moderate IV hypertrophy, were compared with 16 age-matched hypertensive patients with similar degree of IV hypertrophy and 16 age-matched healthy sedentary controls. All the participants underwent echocardiogram and 12-lead electrocardiogram. QT dispersion was defined as the difference between maximum and minimum QT intervals in the different leads. QT dispersion was corrected (QTc) for heart rate according to Bazett's formula. The results showed in athletes and hypertensive patients comparable IV mass (258.2 +/- 14.2 vs. 262.4 +/- 16.8 g, ns), which was significantly higher than that of controls (p < 0.001). Trained subjects had QT dispersion (38.6 +/- 10.2 ms) and QTc dispersion (39.4 +/- 11.3 ms) significantly lower than hypertensive patients (QT dispersion: 68.4 +/- 11.4ms; QTc dispersion: 72.2 +/- 8.4, p < 0.001) and comparable with controls (QT dispersion: 44.3 +/- 8.4 ms; QTc dispersion: 46.2 +/- 6.2 ms, ns). In conclusion, in elderly athletes training-induced myocardial hypertrophy was characterized by a QT dispersion significantly lower than hypertensive myocardial hypertrophy. This could provide a simple and inexpensive screening method for differentiating physiologic from pathologic myocardial hypertrophy in elderly subjects
Left ventricular diastolic function and carotid artery wall in elderly athletes and sedentary controls
No full textAdvancing age is characterized by structural and functional change of left ventricle (LV) and large elastic arteries. Recent advances in tissue Doppler imaging (TDI) and integrated backscatter (IBS), new ultrasound tools, have allowed non-invasive assessment of structural and functional characterization of myocardium and artery wall. Our aim was to compare LV diastolic function and carotid artery remodeling in elderly athletes and sedentary controls. Twenty-five elderly athletes (males, aged 68.6 +/- 4.2 years) were compared to 25 age-sex-matched sedentary controls. All the subjects underwent either conventional Doppler echocardiography with pulsed TDI to evaluate LV diastolic function, and conventional ultrasonography and integrated backscatter (IBS) analysis to evaluate the carotid wall. Corrected IBS values (C-IBS) were obtained by subtracting the IBS value of the adventitia. Body mass index and blood pressure were not different in the two groups; athletes showed lower heart rate (P < 0.0001) and, as expected, higher LV mass than sedentary subjects (P < 0.0001). Transmitral Doppler analysis showed in trained subjects a significantly lower peak A and a higher E/A ratio (P < 0.001). On regards to TDI measurements, athletes exhibited a higher Em, a lower Am, and, subsequently, an increased Em/Am ratio of both lateral wall and septum (P < 0.0001). The IVRTm was shorter in trained subjects (P < 0.001). Athletes showed a lower C-IBS (-26.8 +/- 2.9 vs. -23.4 +/- 3.8 dB, P < 0.001) and a smaller intima-media thickness (IMT: 0.66 +/- 0.14 vs. 0.80 +/- 0.18 mm, P < 0.001) respect to sedentary controls. Moreover, a significant direct correlation was found between Em/Am of LV septal and lateral wall and C-IBS values (respectively, r = 0.62 and r = 0.56, P < 0.001). Thus the aging heart manifests structural and functional changes in response to physical activity. The expected pattern of cardiac and arterial alterations normally seen in response to age is modified in the older athletes, suggesting the exercise training is an effective stimulus in shaping arterial structure and left ventricular function in older heart. It would appear that pulsed TDI and IBS analysis may play an important role in detecting training-induced LV and carotid artery structural and functional modifications
Lifelong physical training prevents the age-related impairment of heart rate variability and exercise capacity in elderly people
No full textAIM: Aging is associated with a reduction on heart rate variability (HRV) and working capacity. Aim of this study was to evaluate in a group of elite master athletes the effect of a lifelong history of endurance running on HRV and exercise working capacity.
METHODS: Twenty athletes (males, age 68.5+/-4.5 years) who practiced endurance running for at least 40 years, and 20 age-sex-matched control subjects with sedentary lifestyle were studied. All the participants underwent a maximal stepwise electrocardiogram (ECG) on effort (work-rate increments of 25 Watts every 2 min) and a 24-hour ECG monitoring.
RESULTS: All the time domain measures of HRV and the LF and HF powers were significantly higher in elderly athletes than in sedentary subjects (P<0.001), while the LF/HF ratio was comparable between the 2 groups. Athletes exhibited significantly higher workload than controls (1610+/-489 vs 687+/-236 W, P<0.0001). Both the groups achieved, at maximum workload, similar heart rate (142+/-10 vs 138+/-18 bpm, ns), systolic blood pressure (226+/-18 vs 220+/-16 mmHg, ns), and rate-pressure product (32,596+/-2952 vs 30,838+/-3675, ns). Maximum work-rate attained in athletes was 225 W. By contrast, none of the controls reached a work-rate higher than 150 W. In the whole group we also showed a positive correlation between the time domain HRV parameter SDNN and maximum workload (r=0.58, P<0.001).
CONCLUSION: Long-term endurance training induces in elderly subjects an increased HRV and a higher exercise working capacity, which are well-established predictors of cardiovascular and overall mortality
Subclinical cardiac involvement in patients with facioscapulohumeral muscular dystrophy
No full textMyocardial involvement is a common finding in certain myopathics, while it has not been extensively investigated in facioscapulohumeral muscular dystrophy (FSHD1A). Aim of this study was to assess in FSHD1A patients the electrical and functional properties of the myocardium. Twenty-four patients with FSHD1A (mean age 41.2 +/- 14.5 years) and 24 matched healthy subjects were studied. Standard- and signal-averaged electrocardiography were recorded to determine QT dispersion and the presence of ventricular late potentials (VLPs). Standard echocardiography with systo-diastolic variations of integrated backscatter signal (CV-IBS) were performed to assess functional properties of the myocardium. Compared with control subjects, patients with FSHD1A had significantly lower CV-IBS and higher QT dispersion. Nine patients had positive VLPs. QT and QTc dispersion were inversely related to CV-IBS at both septum and posterior wall levels. Moreover, septal CV-IBS was inversely related to the Kpnl-BinI4q fragment size. These results suggest a subclinical cardiac involvement in FSHD1A patients, which can represent a substrate for ventricular arrhythmias and heart failure. (c) 2005 Elsevier B.V. All rights reserved
Antihypertensive effect of oral potassium aspartate supplementation in mild to moderate arterial hypertension
No full textBACKGROUND: Previous studies showed that potassium chloride (48-120 mmol/day) supplementation reduced arterial blood pressure (BP) in hypertensive patients.
OBJECTIVES: Our aim was to evaluate the effect of a lower dose of potassium aspartate salt on BP in individuals with essential arterial hypertension.
METHODS: One hundred and four patients (65 males, age 53 +/- 12 years) with mild to moderate essential hypertension (systolic/diastolic BP 154.2/96.2 +/- 10.8/5.4 mmHg) were allocated in two comparable groups of 52 to receive or not 30 mmol/day per os of potassium aspartate supplementation for four weeks. Office and 24-h BP, as well as serum and urinary electrolytes, were measured at baseline and at the follow-up visit after four weeks.
RESULTS: Office and 24-h BP did not change in the control group, while these values were significantly reduced in the potassium supplementation group. Changes in office (systolic BP: 154.4 +/- 8.2 vs. 142.2 +/- 7.6 mmHg; diastolic BP: 95.0 +/- 5.6 vs. 87.2 +/- 4.3 mmHg, P < 0.001 for both) and 24-h BP (systolic BP: 142.7 +/- 8.2 vs. 134.8 +/- 6.3 mmHg; diastolic BP: 90.8 +/- 4.4 vs. 84.6 +/- 3.8 mmHg, P < 0.001 for both) following potassium supplementation were highly significant. The changes in day time and night time BP were similar. The treated group showed significantly increased potassium serum level and 24-h urinary excretion of potassium (P < 0.01 in both cases) after four weeks, while the untreated group showed no significant changes of the same parameters. Urinary Na/K ratio decreased significantly with potassium supplementation (P < 0.001). In the treated group changes in office (r = 0.58, P < 0.001) and 24-h SBP (r = 0.51, P < 0.001), but not in DBP (r = 0.29 and r = 0.25, n.s.), correlated positively with the urinary Na/K ratio at baseline.
CONCLUSIONS: A relatively low supplementation of 30 mmol/day of potassium as aspartate lowered office and 24-h ambulatory BP in subjects with mild to moderate essential hypertension. The antihypertensive effect was sustained throughout the day, and was greater in the patients with high basal urinary Na/K ratio
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