199 resultados para Fetal heart rate
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Background: The Borg Scale may be a useful tool for heart failure patients to self-monitor and self-regulate exercise on land or in water (hydrotherapy) by maintaining the heart rate (HR) between the anaerobic threshold and respiratory compensation point. Methods and Results: Patients performed a cardiopulmonary exercise test to determine their anaerobic threshold/respiratory compensation points. The percentage of the mean HR during the exercise session in relation to the anaerobic threshold HR (%EHR-AT), in relation to the respiratory compensation point (%EHR-RCP), in relation to the peak HR by the exercise test (%EHR-Peak) and in relation to the maximum predicted HR (%EHR-Predicted) was calculated. Next, patients were randomized into the land or water exercise group. One blinded investigator instructed the patients in each group to exercise at a level between ""relatively easy and slightly tiring"". The mean HR throughout the 30-min exercise session was recorded. The %EHR-AT and %EHR-Predicted did not differ between the land and water exercisegroups, but they differed in the %EHR-RCP (95 +/- 7 to 86 +/- 7. P<0.001) and in the %EHR-Peak (85 +/- 8 to 78 +/- 9, P=0.007). Conclusions: Exercise guided by the Borg scale maintains the patient's HR between the anaerobic threshold and respiratory compensation point (ie, in the exercise training zone). (Circ J 2009; 73: 1871-1876)
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beta-blockers, as class, improve cardiac function and survival in heart failure (HF). However, the molecular mechanisms underlying these beneficial effects remain elusive. In the present study, metoprolol and carvedilol were used in doses that display comparable heart rate reduction to assess their beneficial effects in a genetic model of sympathetic hyperactivity-induced HF (alpha(2A)/alpha(2C)-ARKO mice). Five month-old HF mice were randomly assigned to receive either saline, metoprolol or carvedilol for 8 weeks and age-matched wild-type mice (WT) were used as controls. HF mice displayed baseline tachycardia, systolic dysfunction evaluated by echocardiography, 50% mortality rate, increased cardiac myocyte width (50%) and ventricular fibrosis (3-fold) compared with WT. All these responses were significantly improved by both treatments. Cardiomyocytes from HF mice showed reduced peak [Ca(2+)](i) transient (13%) using confocal microscopy imaging. Interestingly, while metoprolol improved [Ca(2+)](i) transient, carvedilol had no effect on peak [Ca(2+)](i) transient but also increased [Ca(2+)] transient decay dynamics. We then examined the influence of carvedilol in cardiac oxidative stress as an alternative target to explain its beneficial effects. Indeed, HF mice showed 10-fold decrease in cardiac reduced/oxidized glutathione ratio compared with WT, which was significantly improved only by carvedilol treatment. Taken together, we provide direct evidence that the beneficial effects of metoprolol were mainly associated with improved cardiac Ca(2+) transients and the net balance of cardiac Ca(2+) handling proteins while carvedilol preferentially improved cardiac redox state. (C) 2008 Elsevier Inc. All rights reserved.
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The aim of this study was to evaluate (1) the prevalence of periodic leg movements during sleep (PLMs) in a consecutive sample of congestive heart failure (CHF) outpatients; (2) the presence of correlation between PLMs, subjective daytime sleepiness, and sleep architecture; and (3) the heart rate response to PLMs in CHF. Seventy-nine [50 men, age 59 +/- 11 years, body mass index (BMI) 26 +/- 5 kg/m(2)] consecutive adult stable outpatients with CHF [left ventricular ejection fraction (LVEF) 36 +/- 6%] were prospectively evaluated. The patients underwent assessment of echocardiography, sleepiness (Epworth Scale), and overnight in-lab polysomnography. Fifteen patients (19%) had PLM index > 5. These subjects were similar in sex distribution, BMI, subjective somnolence, LVEF, and apnea-hypopnea index (AHI), but were significantly older than subjects without PLMs. Sleep architecture was similar in subjects with and without PLMs. There was a small but significant elevation of heart rate after PLMs (80.1 +/- 9.4 vs. 81.5 +/- 9.2; p < 0.001). The cardiac acceleration was also present in absence of electroencephalogram activation. The prevalence of PLMs in consecutive sample of adult CHF outpatients was 19%. There were no differences in subjective daytime sleepiness, sleep architecture, AHI, and severity of CHF in subjects with and without PLMs. PLMs caused a small but statistically significant cardiac acceleration.
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Bliacheriene F, Carmona MJC, Barretti CFM, Haddad CMF, Mouchalwat ES, Bortlotto MRFL, Francisco RPV, Zugaib M - Use of a Minimally Invasive Uncalibrated Cardiac Output Monitor in Patients Undergoing Cesarean Section under Spinal Anesthesia: Report of Four Cases. Background and Objectives: Hemodynamic changes are observed during cesarean section under spinal anesthesia. Non-invasive blood pressure (BP) and heart rate (HR) measurements are performed to diagnose these changes, but they are delayed and inaccurate. Other monitors such as filling pressure and cardiac output (CO) catheters with external calibration are very invasive or inaccurate. The objective of the present study was to report the cardiac output measurements obtained with a minimally invasive uncalibrated monitor (LiDCO rapid) in patients undergoing cesarean section under spinal anesthesia. Case report: After approval by the Ethics Commission, four patients agreed to participate in this study. They underwent cesarean section under spinal anesthesia while at the same time being connected to the LiDCO rapid by a radial artery line. Cardiac output, HR, and BP were recorded at baseline, after spinal anesthesia, after fetal and placental extraction, and after the infusion of oxytocin and metaraminol. We observed a fall in BP with an increase of HR and CO after spinal anesthesia and oxytocin infusion; and an increase in BP with a fall in HR and CO after bolus of the vasopressor. Conclusions: Although this monitor had not been calibrated, it showed a tendency for consistent hemodynamic data in obstetric patients and it may be used as a therapeutic guide or experimental tool.
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A number of studies conducted in humans and in animals have observed that events occurring early in life are associated with the development of diseases in adulthood. Salt overload and restriction during pregnancy and lactation are responsible for functional (hemodynamic and hormonal) and structural alterations in adult offspring. Our group observed that lower birth weight and insulin resistance in adulthood is associated with salt restriction during pregnancy On the other hand, perinatal salt overload is associated with higher blood pressure and higher renal angiotensin II content in adult offspring. Therefore, we hypothesised that renin-angiotensin system (RAS) function is altered by changes in sodium intake during pregnancy. Such changes may influence fetoplacental blood flow and thereby fetal nutrient supply, with effects on growth in utero and, consequently, on birth weight. Female Wistar rats were fed low-salt (LS), normal-salt (NS), or high-salt (HS) diet, starting before conception and continuing until day 19 of pregnancy, Blood pressure, heart rate, fetuses and dams` body weight, placentae weight and litter size were measured on day 19 of pregnancy. Cardiac output, uterine and placental blood flow were also determined on day 19. Expressions of renin-angiotensin system components and of the TNF-alpha gene were evaluated in the placentae. Plasma renin activity (PRA) and plasma and tissue angiotensin-converting enzyme (ACE) activity, as well as plasma and placental levels of angiotensins I, II, and 1-7 were measured. Body weight and kidney mass were greater in HS than in NS and LS dams. Food intake did not differ among the maternal groups. Placental weight was lower in LS dams than in NS and HS dams. Fetal weight was lower in the US group than in the NS and HS groups. The PRA was greater in IS dams than in NS and HS dams, although ACE activity (serum, cardiac, renal, and placental) was unaffected by the level of sodium intake. Placental levels of angiotensins I and II were lower in the HS group than in the ISIS and IS groups. Placental angiotensin receptor type 1 (AT(1)) gene expression and levels of thiobarbituric acid reactive substances (TBARS) were higher in HS dams, as were uterine blood flow and cardiac output. The degree of salt intake did not influence plasma sodium, potassium or creatinine. Although fractional sodium excretion was higher in HS dams than in NS and LS dams, fractional potassium excretion was unchanged. In conclusion, findings from this study indicate that the reduction in fetal weight in response to salt restriction during pregnancy does not involve alterations in uterine-placental perfusion or the RAS. Moreover, no change in fetal weight is observed in response to salt overload during pregnancy. However, salt overload did lead to an increase in placental weight and uterine blood flow associated with alterations in maternal plasma and placental RAS. Therefore, these findings indicate that changes in salt intake during pregnancy lead to alterations in uterine-placental perfusion and fetal growth. (C) 2008 Elsevier Inc. All rights reserved.
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Background: Studies have investigated the influence of neuromuscular electrostimulation on the exercise/muscle capacity of patients with heart failure (HF), but the hemodynamic overload has never been investigated. The aim of our study was to evaluate the heart rate (HR), systolic and diastolic blood pressures in one session of strength exercises with and without neuromuscular electrostimulation (quadriceps) in HF patients and in healthy subjects. Methods: Ten (50% male) HF patients and healthy subjects performed three sets of eight repetitions with and without neuromuscular electrostimulation randomly, with one week between sessions. Throughout, electromyography was performed to guarantee the electrostimulation was effective. The hemodynamic variables were measured at rest, again immediately after the end of each set of exercises, and during the recovery period. Results: Systolic and diastolic blood pressures did not change during each set of exercises among either the HF patients or the controls. Without electrostimulation: among the controls, the HR corresponding to the first (85 +/- 13 bpm, p = 0.002), second (84 +/- 10 bpm, p < 0.001), third (89 +/- 17, p < 0.001) sets and recuperation (83 +/- 16 bpm, p = 0.012) were different compared to the resting HR (77 bpm). Moreover, the recuperation was different to the third set (0.018). Among HF patients, the HR corresponding to the first (84 +/- 9 bpm, p = 0.041) and third (84 +/- 10 bpm, p = 0.036) sets were different compared to the resting HR (80 +/- 7 bpm), but this increase of 4 bpm is clinically irrelevant to HF. With electrostimulation: among the controls, the HR corresponding to the third set (84 +/- 9 bpm) was different compared to the resting HR (80 +/- 7 bmp, p = 0.016). Among HF patients, there were no statistical differences between the sets. The procedure was well tolerated and no subjects reported muscle pain after 24 hours. Conclusions: One session of strength exercises with and without neuromuscular electrostimulation does not promote a hemodynamic overload in HF patients. (Cardiol J 2011; 18,1: 39-46)
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In recent years, beta-blocker therapy has become a primary pharmacologic intervention in patients with heart failure by blocking the sympathetic activity. To compare the exercise training`s sympathetic blockade in healthy subjects (athletes) and the carvedilol`s sympathetic blockade in sedentary heart failure patients by the evaluation of the heart rate dynamic during an exercise test. A total of 26 optimized and 49 nonoptimized heart failure patients in a stable condition (for, at least, 3 months), 15 healthy athletes and 17 sedentary healthy subjects were recruited to perform a cardiopulmonary exercise test. The heart rate dynamic (rest, reserve, peak and the peak heart rate in relation to the maximum predicted for age) was analyzed and compared between the four groups. The heart rate reserve was the same between optimized (48 +/- 15) and nonoptimized (49 +/- 18) heart failure patients (P < 0.0001). The athletes (188 +/- 9) showed a larger heart rate reserve compared to sedentary healthy subjects (92 +/- 10, P < 0.0001). Athletes and healthy sedentary reached the maximum age-predicted heart ratefor their age, but none of the heart failure patients did. The carvedilol`s sympathetic blockade occurred during the rest and during the peak effort in the same proportion, but the exercise training`s sympathetic blockade in healthy subjects occurred mainly in the rest.
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Background: A previous study associated CD34(+) levels with NYHA functional class in heart failure patients. The aim of this study was to correlate CD34(+) levels to exercise capacity, functional class, quality of life and norepinephrine in heart failure patients. Methods: Twenty three sedentary patients (52 +/- 7 years, 78% male) answered the Minnesota Living with Heart Failure Questionnaire and rested for 20 minutes before an investigator collect a blood sample. After this, patients performed a cardiopulmonary exercise test to determine the heart rate at anaerobic and ventilatory threshold and oxygen consumption at peak effort, at anaerobic and ventilatory threshold. One other blood sample was collected during the peak effort to investigate the norepinephrine and CD34(+) levels. Results: Rest percentage of CD34(+) did not show correlation with: left ventricle ejection fraction (r = 0.03, p = 0.888), peakVO(2) (r = 0.32, p = 0.13), VO(2) at anaerobic threshold (VO(2)AT) (r = 0.03, p = 0.86), VO(2) at ventilatory threshold (VO(2)VT) (r = 0.36, p = 0.08), NYHA functional class (r = -0.2, p = 0.35), quality of life (Minnesota) (r = -0.17, p = 0.42). CD34(+) did not show correlation, either, with: peak VO(2) (r = 0.38, p = 0.06), VO(2)AT (r = 0.09, p = 0.65), VO(2)VT (r = 0.43, p = 0.4), NYHA functional class (r = -0.13, p = 0.54), quality of life (r = 0.00, p = 0.99). Conclusions: CD34(+) levels did not correlate with exercise capacity, functional class, quality of life and norepinephrine. Percentage of CD34(+) levels did not increase during the cardiopulmonary exercise test in heart failure patients. (Cardiol J 2009; 16, 5: 426-431)
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Background: Previous studies have associated neurohumoral excitation, as estimated by plasma norepinephrine levels, with increased mortality in heart failure. However, the prognostic value of neurovascular interplay in heart failure (HF) is unknown. We tested the hypothesis that the muscle sympathetic nerve activity (MSNA) and forearm blood flow would predict mortality in chronic heart failure patients. Methods: One hundred and twenty two heart failure patients, NYHA II-IV, age 50 +/- 1 ys, LVEF 33 +/- 1%, and LVDD 7.1 +/- 0.2 mm, were followed up for one year. MSNA was directly measured from the peroneal nerve by microneurography. Forearm blood flow was obtained by venous occlusion plethysmography. The variables were analyzed by using univariate, stepwise multivariate Cox proportional hazards analysis, and Kaplan-Meier analysis. Results: After one year, 34 pts died from cardiac death. The univariate analysis showed that MSNA, forearm blood flow, LVDD, LVEF, and heart rate were significant predictors of mortality. The multivariate analysis showed that only MSNA (P = 0.001) and forearm blood flow (P = 0.003) were significant independent predictors of mortality. On the basis of median levels of MSNA, survival rate was significantly lower in pts with >49 bursts/min. Similarly, survival rate was significantly lower in pts with forearm blood flow <1.87 ml/min/100 ml (P = 0.002). Conclusion: MSNA and forearm blood flow predict mortality rate in patients with heart failure. It remains unknown whether therapies that specifically target these abnormalities will improve survival in heart failure. (C) 2008 Elsevier Ireland Ltd. All rights reserved.
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Background: Color Doppler myocardial imaging (CDMI) allows the calculation of local longitudinal or radial strain rate (SR) and strain (epsilon). The aims of this study were to determine the feasibility and reproducibility of longitudinal and radial SR and epsilon in neonates during the first hours of life and to establish reference values. Methods: Data were obtained from 55 healthy neonates (29 male; mean age, 20 +/- 14 hours; mean birth weight, 3,174 +/- 374 g). Apical and parasternal views quantified regional longitudinal and radial SR and epsilon in differing ventricular wall segments. Values at peak systole, early diastole, and late diastole were calculated from the extracted curves. CDMI data acquired at 300 +/- 50 frames/s were analyzed offline. Three consecutive cardiac cycles were measured during normal respiration. The timing of specific systolic or diastolic regional events was determined. Multiple comparisons between walls and segments were made. Results: Left ventricular (LV) longitudinal deformation showed basal differences compared with apical segments within one specific wall. Right ventricular (RV) longitudinal deformation was not homogeneous, with significant differences between basal and apical segments. Longitudinal 3 values were higher in the RV free basal and middle wall segments compared with the left ventricle. In the RV free wall apical segment, longitudinal SR and 3 were maximal. LV systolic SR and epsilon values were higher radially compared with longitudinally (radial peak systolic SR midportion, 2.9 +/- 0.6 s(-1); radial peak systolic epsilon 53.8 +/- 19%; longitudinal peak systolic SR midportion, -1.8 +/- 0.5 s(-1); longitudinal peak systolic epsilon, -24.8 +/- 3%; P < .01). Longitudinal systolic epsilon and SR interobserver variability values were 1.2% and 0.7%, respectively. Conclusion: Ultrasound-based SR and 3 imaging is a practical and reproducible clinical technique in neonates, allowing the calculation of regional longitudinal and radial deformation in RV and LV segments. These regional SR and epsilon indices represent new, noninvasive parameters that can quantify normal neonate regional cardiac function. Independent from visual interpretation, they can be used as reference values for diagnosis in ill neonates. (J Am Soc Echocardiogr 2009;22:369-375.)
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Goals: To assess maternal and fetal outcomes and clinical management of pregnancy in patients with autoimmune hepatitis (AIH). Background: There is a paucity of information about maternal and fetal outcomes, and AIH activity during pregnancy and in the postpartum period. There is no consensus about the administration of azathioprine during pregnancy and breastfeeding. Study: Retrospective analysis of 54 pregnancies (3 still in progress) in 39 AIH patients. Results: The median age at conception was 24 years, and 68.4% of women had liver cirrhosis. Before conception and in early pregnancy, azathioprine and prednisone were administered in 48.1%, but treatment regimen vas usually changed further to 20 mg/d prednisone and 20.4%, were off treatment. There were 36 livebirths, and fetal loss rates were 29.4% (13 miscarriages, 1 stillbirth, and 1 ectopic pregnancy). Preterm birth rate was 11.8%. In 2 cases, there was acute fetal distress; and in 2 others congenital malformations (3.9%). The rate of serious maternal complication was 7.8%, with no deaths. There were no flares in 41.2% pregnancies, but aminotransferase elevations occurred in 54.9%, 31.4% of which were true AIH relapses, only registered in the postpartum period. Conclusions: Despite the high fetal miscarriage rate, pregnancy in AIH was safe. Patients needed careful monitoring, especially in the postpartum period because of relapses. There was no evidence of a cause and effect relationship among azathioprine administration and premature births and congenital abnormalities, but more studies are necessary. Higher doses of prednisone may be an alternative option for those who prefer azathioprine withdrawal during pregnancy.
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Background: The relation between left ventricular filing velocities determined by Doppler echocardiography and autonomic nervous system function assessed by heart rate variability (HRV) is unclear. The aim of this study was to evaluate the influence of the autonomic nervous system assessed by the time and frequency domain indices of HRV in the Doppler indices of left ventricular diastolic filling velocities in patients without heart disease. Methods: We studied 451 healthy individuals (255 female [56.4%]) with normal blood pressure, electrocardiogram, chest x-ray, and treadmill electrocardiographic exercise stress test results, with a mean age of 43 +/- 12 (range 15-82) years, who underwent transthoracic Doppler echocardiography and 24-hour electrocardiographic ambulatory monitoring. We studied indices of HRV on time (standard deviation [SD] of all normal sinus RR intervals during 24 hours, SD of averaged normal sinus RR intervals for all 5-minute segments, mean of the SD of all normal sinus RR intervals for all 5-minute segments, root-mean-square of the successive normal sinus RR interval difference, and percentage of successive normal sinus RR intervals > 50 ms) and frequency (low frequency, high frequency, very low frequency, low frequency/high frequency ratio) domains relative to peak flow velocity during rapid passive filling phase (E), atrial contraction (A), E/A ratio, E-wave deceleration time, and isovolumic relaxation time. Statistical analysis was performed with Pearson correlation and logistic regression. Results: Peak flow velocity during rapid passive filling phase (E) and atrial contraction (A), E/A ratio, and deceleration time of early mitral inflow did not demonstrate a significant correlation with indices of HRV in time and frequency domain. We found that the E/A ratio was < 1 in 45 individuals (10%). Individuals with an E/A ratio < 1 had lower indices of HRV in frequency domain (except low frequency/high frequency) and lower indices of the mean of the SD of all normal sinus RR intervals for all 5-minute segments, root-mean-square of the successive normal sinus RR interval difference, and percentage of successive normal sinus RR intervals > 50 ms in time domain. Logistic regression demonstrated that an E/A ratio < 1 was associated with lower HF. Conclusion: Individuals with no evidence of heart disease and an E/A ratio < 1 demonstrated a significant decrease in indexes of HRV associated with parasympathetic modulation. (J Am Soc Echocardiogr 2010;23: 762-5.)
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Introduction. Orthotopic heart transplantation renders the recipient denervated. This remodeling of the intrinsic cardiac nervous system should be taken in account during functional evaluation for allograft coronary artery disease. Dobutamine stress echocardiography (DSE) has been used to detect patients at greater risk. The aim of this study was to determine whether patients with various autonomic response levels, and supposed reinnervation patterns, show the same response to DSE. Methods. We studied 20 patients who had survived more than 5 years after orthotopic heart transplantation. All patients underwent a Holter evaluation. We considered patients with low variability to be those with less than a 40-bpm variation from the lowest to highest heart rate, so-called ""noninnenervated"" (group NI). Patients who had 40-bpm or more variation were considered to show high variability and called ""reinnervated"" (group RI). After that, all patients performed an ergometric test and DSE. Results. Groups were defined as NI (n = 9) and RI (n = 11). Ergometric tests confirmed this response with NI patients showing less variability when compared to RI patients (P = .0401). During DSE, patients showed similar median heart rate responses according to the dobutamine dose. Spearmen correlation showed r = 1.0 (P = .016). Conclusions: DES was effective to reach higher heart rates, probably related to catecholamine infusion. These findings may justify a better response when evaluating cardiac allograft vasculopathy in heart transplant patients.
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Objective: Severe fetal anemia and cardiac compromise are important causes of nonimmune hydrops fetalis, and fetal recovery also depends on the degree of fetal heart compromise. The aim of this study was to report the fetal cardiac troponin T (cTnT) levels in cases of nonimmune fetal hydrops. Methods: Fetal cTnT was analyzed on 7 occasions in 5 cases of nonimmune fetal hydrops ( twice in 2 cases). Results: In 3 of 4 fetuses in which intrauterine death occurred, fetal cTnT levels were increased. The only fetus that survived in this series showed decreased levels of cTnT before birth. Conclusion: Fetal cTnT levels may be a marker of fetal prognosis in cases of fetal hydrops. Copyright (C) 2009 S. Karger AG, Basel
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The incidence of sudden unexpected death in epilepsy (SUDEP) has been estimated from 0.5-1.4/1,000 person-years in people with treated epilepsy, and 9/1,000 person-years in candidates for epilepsy surgery. Potential risk factors for SUDEP include: age, early onset of epilepsy, duration of epilepsy, uncontrolled seizures, seizure type and winter temperatures. The arrythmogenic side-effect of antiepileptic drugs and seizures may increase the risk of SUDEP. In this report, we describe a patient with prolonged post-ictal tachycardia in EEG video recordings with a typical case of SUDEP: a 16-year-old boy with medically intractable complex partial seizures. Magnetic resonance imaging revealed left mesial temporal sclerosis. During non-invasive video-EEG monitoring, the patient presented a post-ictal heart rate increased for five hours. Two months after video-EEG, he died from SUDEP during a tonic-clonic secondary generalized seizure. The possibility of cardiac involvement in the pathogenesis of SUDEP has been suggested by many studies. Evaluation of this patient with EEG-video monitoring, including measurement of heart rate, contributed to an identification of ictal tachycardia that may have played a role in the SUDEP. Premature mortality seems to be increased in patients with epilepsy, and cardiac abnormalities may be a possible cause of SUDEP. (Cardiol J 2011; 18, 2: 194-196)