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Objectives: With the emergence of targeted cell transplantation and gene therapy, there is a need for minimally invasive tissue access to facilitate delivery of therapeutic substrate. The objective of this study was to demonstrate the suitability of an endovascular device which is able to directly access tissue and deliver therapeutic agent to the heart, kidney and pancreas without need to seal the penetration site.Methods: In vivo experiments were performed in 30 swine, including subgroups with follow-up to evaluate complications. The previously described trans-vessel wall (VW) device was modified to be sharper and not require tip detachment to seal the VW. Injections into targets in the heart (n = 13, 24-h follow-up n = 5, 72-h follow-up n = 3), kidney (n = 8, 14-day follow-up n = 3) and pancreas (n = 5) were performed. Some animals were used for multiple organ injections. Follow-up consisted of clinical monitoring, angiography and necropsy. Transvenous (in heart) and transarterial approaches (in heart, kidney and pancreas) were used. Injections were targeted towards the subepicardium, endomyocardium, pancreas head and tail, and kidney subcapsular space and cortex.Results: Injections were successful in target organs, visualized by intraparenchymal contrast on fluoroscopy and by necropsy. No serious complications (defined as heart failure or persistent arrhythmia, haemorrhage requiring treatment or acute kidney injury) were encountered over a total of 157 injections.Conclusions: The trans-VW device can achieve superselective injections to the heart, pancreas and kidney for delivery of therapeutic substances without tip detachment. All parts of these organs including the subepicardium, pancreas tail and renal subcapsular space can be efficiently reached. [ABSTRACT FROM AUTHOR]

That muscular blood flow may reach 2.51 kg-1 min-1 in the quadriceps muscle has led to the suggestion that muscular vascular conductance must be restrained during whole body exercise to avoid hypotension. The main aim of this study was to determine the maximal arm and leg muscle vascular conductances (VC) during leg and arm exercise, to find out if the maximal muscular vasodilatory response is restrained during maximal combined arm and leg exercise. Six Swedish elite cross-country skiers, age (mean ± S.E.M.) 24 ± 2 years, height 180 ± 2 cm, weight 74 ± 2 kg, and maximal oxygen uptake (VO2,max) 5.1 ± 0.1 1 min-1 participated in the study. Femoral and subclavian vein blood flows, intra-arterial blood pressure, cardiac output, as well as blood gases in the femoral and subclavian vein, right atrium and femoral artery were determined during skiing (roller skis) at ∼ 76% of VO2,max and at VO2,max with different techniques: diagonal stride (combined arm and leg exercise), double poling (predominantly arm exercise) and leg skiing (predominantly leg exercise). During submaximal exercise cardiac output (26-27 1 min-1), mean blood pressure (MAP) (∼ 87 mmHg), systemic VC, systemic oxygen delivery and pulmonary VO2 (∼ 41 min-1) attained similar values regardless of exercise mode. The distribution of cardiac output was modified depending on the musculature engaged in the exercise. There was a close relationship between VC and VO2 in arms (r = 0.99, P < 0.001) and legs (r = 0.98, P < 0.05). Peakarm VC (63.7 ± 5.6 ml min-1 mmHg-1) was attained during double poling, while peak leg VC was reached at maximal exercise with the diagonal technique (109.8 ± 11.5 ml min-1 mmHg-1) ... [ABSTRACT FROM AUTHOR]

To study the role of muscle mass and muscle activity on lactate and energy kinetics during exercise, whole body and limb lactate, glucose, and fatty acid fluxes were determined in six elite cross-country skiers during roller-skiing for 40 min with the diagonal stride (Continuous Arm + Leg) followed by 10 min of double poling and diagonal stride at 72-76% maximal O[sub 2] uptake. A high lactate appearance rate (R[sub a], 184 ± 17 µmol·kg[sup -1]·min[sup -1]) but a low arterial lactate concentration (∼2.5 mmol/l) were observed during Continuous Arm + Leg despite a substantial net lactate release by the arm of ∼2.1 mmol/min, which was balanced by a similar net lactate uptake by the leg. Whole body and limb lactate oxidation during Continuous Arm + Leg was ∼45% at rest and ∼95% of disappearance rate and limb lactate uptake, respectively. Limb lactate kinetics changed multiple times when exercise mode was changed. Whole body glucose and glycerol turnover was unchanged during the different skiing modes; however, limb net glucose uptake changed severalfold. In conclusion, the arterial lactate concentration can be maintained at a relatively low level despite high lactate R[sub a] during exercise with a large muscle mass because of the large capacity of active skeletal muscle to take up lactate, which is tightly correlated with lactate delivery. The limb lactate uptake during exercise is oxidized at rates far above resting oxygen consumption, implying that lactate uptake and subsequent oxidation are also dependent on an elevated metabolic rate. The relative contribution of whole body and limb lactate oxidation is between 20 and 30% of total carbohydrate oxidation at rest and during exercise under the various conditions. Skeletal muscle can change its limb net glucose uptake severalfold within minutes, causing a redistribution of the available glucose because whole body glucose turnover was unchanged. [ABSTRACT FROM AUTHOR]

Abstract. Jensen-Urstad M, Samad BA, Jensen-Urstad K, Hulting J, Ruiz H, Bouvier F, Höjer J (Karolinska Hospital, Karolinska Institute, Stockholm; Söder Hospital, Karolinska Institute, Stockholm; Karolinska Hospital, Karolinska Institute, Stockholm; and Söder Hospital, Karolinska Institute, Stockholm, Sweden). Risk assessment in patients with acute myocardial infarction treated with thrombolytic therapy. J Intern Med 2001; 249: 527–537. Objective. Several noninvasive methods have prognostic information regarding mortality and new coronary events after an acute myocardial infarction (AMI). The practical for clinical decision-making in the immediate postmyocardial infarction (MI) period is, however, less evident. We investigated consecutive patients with AMI treated with thrombolysis to further clarify this issue. Design. A total of 100 patients (27% women) aged 64 ± 9 years (mean ± SD) were studied. Risk assessment based on a clinical score system, myocardial perfusion scintigraphy single photon emission computed tomography (SPECT) at rest and during adenosine stress, echocardiography, radionuclide angiography, symptom-limited exercise stress test, and 24-h Holter ECG recording with ST-analysis and analysis of heart rate variability (HRV) were performed 5–8 days after hospital admission. Mortality, nonfatal reinfarction, and the need for revascularization were followed during 12 months. Setting. A university hospital. Results. A total of 6 patients died, seven had a nonfatal reinfarction, and 23 were revascularized. Inability to perform an exercise test (P=0.004) and an ejection fraction (EF) <40% (P=0.002) were the only parameters separating those who died from the survivors. No method could predict a nonfatal reinfarction. Patients suffering either death or nonfatal reinfarction had a clinical risk assessment score 2 points higher (8.8 vs. 6.7, P=0.05) than the group without such events. A positive symptom-limited exercise stress test (P=0.027), ST-depressions on Holter ECG (P=0.04), and reversibility on myocardial perfusion scintigraphy (P=0.029) predicted the need for revascularization. Conclusion. Risk assessment based on clinical information, exercise stress testing, and an estimate of left ventricular function (e.g. via echocardiography) contribute with prognostic information in thrombolysed MI-patients. Additional noninvasive investigations such as adenosine-SPECT, analysis of HRV, and Holter-monitoring do not add to these commonly available tools in risk stratification of subjects at low to medium risk. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Cryoablation is a new alternative to radiofrequency (RF) ablation for treatment of atrioventricular nodal reentry tachycardias (AVNRT). Mapping with reversible effect on the arrhythmia substrate or the AV node can be done before irreversible ablation is performed. This study evaluates an approach with systematic cryomapping, ablating only in areas with prompt effect on the arrhythmia substrate and evaluates whether the success rates and procedure times are similar to RF ablation. METHODS AND RESULTS: Seventy-five consecutive patients with typical slow-fast AVNRT were studied. Cryomapping at -30 degrees C was performed before ablation with a goal temperature of -70 degrees C for 240 seconds. The ablation procedure was successful in 74 of the 75 patients, giving an acute success rate of 99%. During a mean follow-up of 338 days, 70 of the 74 primarily successfully ablated patients were free from the treated arrhythmia, giving a recurrence rate of 5% and a total success rate of 93%. Total procedure time including a 30-minute test after successful ablation was 126+/-55 minutes. Fluoroscopy time was 18.5+/-14.9 minutes. CONCLUSION: Cryoablation of AVNRT appears to be as effective as RF ablation both acute and in long term with minimal risks for unwanted injuries on the conduction system. The procedure can be done with reasonable procedure and fluoroscopy times. [ABSTRACT FROM AUTHOR]

Objective: To illustrate the geographical West-to-East division of coronary heart disease (CHD) by comparing a population from Sweden, that represents a Western country to a population from Estonia, that represents an Eastern country. Estonia has an approximately 2-4-fold higher CHD prevalence for 55-year-old women and men, respectively, than Sweden.Design: Randomized screening of 35- and 55-year-old men and women in Sollentuna county, Sweden and Tartu county, Estonia. Eight hundred subjects, 100 from each cohort, were invited to participate in the study, 272 Swedes and 277 Estonians participated.Setting: Preventive cardiology, administered by a primary health care centre at the Karolinska Hospital, Sweden and a cardiology centre at Tartu University Hospital, Estonia.Main Outcome Measures: The CHD risk factors (smoking, blood pressure, concentrations of lipoproteins, fibrinogen, and glucose) and certain environmental factors and attitudes related to CHD risk by questionnaires (fat-type and alcohol ingestion, self-assessed rating of CHD susceptibility).Results: Of the 55-year-old men, 57% smoked in Estonia and 20% smoked in Sweden. Similar, although less pronounced differences showing higher smoking prevalence, were seen for 35-year-old Estonian men and women, whilst for 55-year-old women, less than 20% smoked in either country. Estonian 55-year-old women had lower HDL cholesterol and higher LDL cholesterol serum concentrations than Swedish 55-year-old women. Estonians reportedly ate food containing more saturated fats than Swedes, as indicated by the scale-score questionnaire. Estonians, relative to Swedes, rated their chance of developing CHD higher, and paradoxically, Estonians did to a much lesser degree believe that life style influences the risk of developing CHD.Conclusions: Elevated smoking prevalence is a striking difference between the Estonian and Swedish populations likely to explain the much higher CHD prevalence in Estonian men. The lower HDL cholesterol and higher LDL cholesterol in Estonian 55-year-old women may explain the higher CHD prevalence in Estonian women. Furthermore, the SWESTONIA CHD study (i.e. comparison between Sweden and Estonia) shows several environmental differences between the countries populations related to fat content in food, alcohol drinking patterns, and views on CHD risk and the importance of lifestyle intervention, that could contribute to the higher CHD prevalence in Estonia. [ABSTRACT FROM AUTHOR]

Objective: This prospective study was designed to investigate the differences between asymptomatic versus symptomatic arrhythmia as well as left ventricular dysfunction in a consecutive population of patients with persistent atrial fibrillation.Design: A total of 282 consecutive outpatients referred with persistent atrial fibrillation formed the study population. A structured medical history was obtained. A two-dimensional transthoracic echocardiography to assess the left ventricular function and a 24-h electrocardiogram (ECG) recording were performed. Irregularity of the heart rhythm was analysed with heart rate variability (HRV) in the time domain as well as maximum and minimum heart rate and the longest pause.Setting: Three university hospitals.Results: The mean age of the patients was 69 years and the mean duration of atrial fibrillation was 7 months. The prevalence of symptomatic patients was 68%, while 32% had no symptoms from atrial fibrillation, left ventricular dysfunction was observed in 20%. Asymptomatic subjects had more often lone atrial fibrillation than those with symptoms. Valvular heart disease was an independent predictor of symptoms while male gender, ischaemic heart disease and a high heart rate were independent predictors of impaired left ventricular function.Conclusion: Valvular heart disease is related to symptoms in persistent atrial fibrillation. Ischaemic heart disease, male gender and a high heart rate are more common in patients with impaired left ventricular function. Compromised left ventricular function does, occur also in asymptomatic subjects underlining the importance of a careful investigation including echocardiography in all subjects with persistent atrial fibrillation. [ABSTRACT FROM AUTHOR]

The objective was to characterise function and morphology of the arterial wall in 9 elderly men (mean age 75±3.4 years) with a history of lifelong regular strenuous exercise. A control group of 11 healthy sedentary or moderately physically active men (74.5±2.7 years) was also studied. With increasing age atherosclerosis becomes more common and endothelium-dependent vasodilation reduced. The effects of training on endothelial function and atherosclerosis have not been studied previously in elderly subjects. High-frequency ultrasound was used to estimate vasodilatory function in the brachial artery. The endothelium-dependent (flow-mediated) and non-endothelium-dependent (nitroglycerine-induced) dilation of the brachial artery were measured. Stasis was used to induce reactive hyperaemia. The carotid arteries were scanned for plaques, intimamedia thickness was measured in the common carotid arteris and arterial wall stiffness was calculated from pulsatile diameter changes in the right carotid artery in relation to blood pressure. The athletes' maximal oxygen uptake during treadmill exercise was 2.90±0.50 l or 41±7 ml•kg[sup-1]. The athletes' and the controls' maximal exercise capacity on a bicycle was 254±38 W and 148±19 W respectively (P<0.001). The athletes' body mass index was 22.6±2.6 kg•m[sup-2] and the controls' body mass index was 25.8±3.5 kg•m[sup-2](P=0.037). Three of 9 athletes had plaques in either or both carotid bifurcations compared with 6 of 11 controls. The athletes had less stiff arteries and better vasodilatory capacity in the brachial artery during increased flow, and borderline significantly greater vasodilation after nitroglycerine. So, elderly athletes with a lifelong training history appear to have better vasodilatory capacity and less stiff arteries than healthy controls. Plaques in the carotid bifurcation were common in both athletes and controls. [ABSTRACT FROM AUTHOR]

Objective: Low heart rate variability (HRV) is, in several patient groups, related to poor prognosis. The underlying mechanisms are still unclear. The aim was to study if there is a relationship between HRV, which is a measure of baroreceptor function, and atherosclerosis.Design: The relationship between heart rate variability and carotid arterial wall stiffness was studied in subjects with type 1 diabetes mellitus in which autonomic dysfunction and early atherosclerosis are common. HRV was assessed from power spectral analysis of 24-h Holter recordings and arterial wall stiffness was assessed from an ultrasound study of the right common carotid artery.Setting: A university hospital.Subjects: Fifty-nine patients (41 +/- 8 years) from the Stockholm Diabetes Intervention Study (SDIS) were investigated. These patients were randomized to intensified conventional treatment or standard treatment approximately 12 years before this study.Results: Patients with stiffer arteries had lower HRV in all spectral bands (r = -0.32 to -0.40, P = 0.06-0.001). This relation remained on correcting for age. All spectral parameters of HRV correlated with the mean HbA1c from 10 years of study (r = -0.37 to -0.40, P = 0.004-0.001).Conclusions: In patients with type 1 diabetes mellitus, heart rate variability and arterial wall stiffness are related to each other. The results suggests that the autonomic nervous system could be a link between diabetes and vascular disease. [ABSTRACT FROM AUTHOR]

Objective: To study whether haemostasis function variables correlate with endothelial function and other vasomotion characteristics of the brachial artery in a randomly selected healthy population of 35-year-old men and women.Design: Endothelial function was measured as flow mediated dilatation (FMD) of the brachial artery during reactive hyperaemia and the nonendothelial dependent dilatation after sublingual nitroglycerin (NTG) was administered. Haemostasis and fibrinolysis function were estimated by analysis of von Willebrand factor, plasminogen activator inhibitor-1, antiplasmin and fibrinogen.Setting: A general medicine research centre and a university hospital.Subjects: Randomly chosen men (n = 53) and women (n = 56).Results: Univariate correlation analysis showed significant correlations between haemostasis factors, conventional risk factors for cardiovascular disease and indices of vasomotion of the brachial artery. In multivariate analysis, with haemostasis variables and conventional risk factors included, antiplasmin was the strongest explanatory variable for FMD. When antiplasmin was removed from the analysis, the r-value dropped from 0.46 to 0.35. Antiplasmin also correlated with NTG-induced dilatation (positively) and brachial diameter at rest (negatively), albeit less consistently.Conclusions: Antiplasmin correlates significantly and independently to FMD, reflecting endothelial function, and also to brachial artery diameter at rest and nitroglycerin-induced dilatation. In multivariate analysis these correlations of antiplasmin to arterial characteristics were stronger than for 'conventional' risk factors, such as smoking, blood pressure and serum cholesterol. [ABSTRACT FROM AUTHOR]

Blood flow changes in the brachial artery of seven subjects during and after submaximal static handgrip contractions were measured by duplex Doppler ultrasound technique. These measurements were compared with the results of occlusion plethysmography, measured immediately (2-3 heartbeats) after. For the combined data from all measurements, a common calibration line could be drawn (linear regression, r=0.92). The flow measurements from the two methods were tested by a four-way analysis of variance and there was no significant difference between the methods during (static) exercise, indicating acceptable coherence. Occlusion plethysmography may well be used for monitoring forearm blood flow during conditions of static exercise. In addition, the cuff occlusion pressure of the plethysmograph (50 mmHg) decreased the blood flow of the brachial artery by approximately 28% as measured by duplex Doppler ultrasound. [ABSTRACT FROM AUTHOR]

Aim: We examined the Fick components together with mitochondrial O2 affinity (p50mito) in defining O2 extraction and O2 uptake during exercise with large and small muscle mass during normoxia (NORM) and hyperoxia (HYPER). Methods: Seven individuals performed 2 incremental exercise tests to exhaustion on a bicycle ergometer (BIKE) and 2 on a 1‐legged knee extension ergometer (KE) in NORM or HYPER. Leg blood flow and VO2 were determined by thermodilution and the Fick method. Maximal ADP‐stimulated mitochondrial respiration (OXPHOS) and p50mito were measured ex vivo in isolated mitochondria. Mitochondrial excess capacity in the leg was determined from OXPHOS in permeabilized fibres and muscle mass measured with magnetic resonance imaging in relation to peak leg O2 delivery. Results: The ex vivo p50mito increased from 0.06 ± 0.02 to 0.17 ± 0.04 kPa with varying substrate supply and O2 flux rates from 9.84 ± 2.91 to 16.34 ± 4.07 pmol O2·s−1·μg−1 respectively. O2 extraction decreased from 83% in BIKE to 67% in KE as a function of a higher O2 delivery and lower mitochondrial excess capacity. There was a significant relationship between O2 extraction and mitochondrial excess capacity and p50mito that was unrelated to blood flow and mean transit time. Conclusion: O2 extraction varies with mitochondrial respiration rate, p50mito and O2 delivery. Mitochondrial excess capacity maintains a low p50mito which enhances O2 diffusion from microvessels to mitochondria during exercise. [ABSTRACT FROM AUTHOR]

Background Atrial fibrillation (AF) is the most common arrhythmia and many AF patients experience a significantly impaired health-related quality of life (HRQOL). AF is also associated with a high risk of stroke and death. Many pharmacologic treatments for AF are ineffective and may have adverse effects. New methods, such as pulmonary vein isolation (PVI), have been developed to treat AF. Aims The aim of this study was to investigate the HRQOL issues in severe symptomatic AF patients before and after pulmonary vein isolation. Methods Forty patients treated with PVI were included of which 36 concluded the study with the self-reported HRQOL questionnaires before and once after PVI. A standardized control group was used. Results Compared to the control group the HRQOL before PVI was significantly lower in all domains except for bodily pain. The preoperative scores were compared with the scores obtained at the follow-up. All subscales of the SF-36 significantly improved after the PVI except for bodily pain, which remained unaltered. Conclusion HRQOL is improved in AF patients with severe symptoms after PVI intervention. [ABSTRACT FROM AUTHOR]

To determine whether conditions for O2 utilization and O2 off-loading from the hemoglobin are different in exercising arms and legs, six cross-country skiers participated in this study. Femoral and subclavian vein blood flow and gases were determined during skiing on a treadmill at ∼76% maximal O2 uptake (Vo2 max) and at Vo2 max with different techniques: diagonal stride (combined arm and leg exercise), double poling (predominantly arm exercise), and leg skiing (predominantly leg exercise). The percentage of O2 extraction was always higher for the legs than for the arms. At maximal exercise (diagonal stride), the corresponding mean values were 93 and 85% (n = 3; P « 0.05). During exercise, mean arm O2 extraction correlated with the Po2 value that causes hemoglobin to be 50% saturated (P50: r = 0.93, P « 0.05), but for a given value of P50, O2 extraction was always higher in the legs than in the arms. Mean capillary muscle O2 conductance of the arm during double poling was 14.5 (SD 2.6) ml·min-1·mmHg-1, and mean capillary Po2 was 47.7 (SD 2.6) mmHg. Corresponding values for the legs during maximal exercise were 48.3 (SD 13.0) ml·min-1, mmHg-1 and 33.8 (SD 2.6) mmHg, respectively. Because conditions for O2 off-loading from the hemoglobin are similar in leg and arm muscles, the observed differences in maximal arm and leg O2 extraction should be attributed to other factors, such as a higher heterogeneity in blood flow distribution, shorter mean transit time, smaller diffusing area, and larger diffusing distance, in arms than in legs. [ABSTRACT FROM AUTHOR]

Abstract Background The objectives of this study were to determine the influence of glucose control on lipoprotein and haemostasis variables in Type 1 diabetes mellitus patients and to evaluate the global impact of these metabolic risk factors on brachial artery reactivity and carotid artery atherosclerosis, stiffness and diameter. Design Follow up of Type 1 diabetes patients randomized to insulin-intensive conventional treatment (ICT, n = 29) or insulin-standard treatment (ST, n = 25) in the Stockholm Diabetes Intervention Study (SDIS) more than 14 years ago. Results The intensive conventional treatment patients had lower glycosylated haemoglobin (HbA1c) compared with the ST patients, i.e. 7·01 (SD 0·51) vs. 8·31 (0·97), while concentrations of the lipoprotein and haemostasis variables analyzed were virtually similar. The carotid artery intima-media area was associated with high HbA1c, high serum (S)-cholesterol levels, and low high-density lipoprotein (HDL)-cholesterol levels. Carotid artery stiffness was associated with high systolic blood pressure, high HbA1c, high fibrinogen, and high HDL-cholesterol. Brachial artery endothelial reactivity was higher for women and those with low S-cholesterol. Conclusion In patients with Type 1 diabetes, glucose control appeared to have no effect on either lipoproteins or haemostasis variable concentrations. Poor glucose control, and high levels of S-cholesterol, systolic blood pressure and plasma fibrinogen were associated with development of atherosclerosis, thus emphasising the importance of global risk factor control in patients with Type 1 diabetes mellitus. [ABSTRACT FROM AUTHOR]

Objectives: To examine the relation between left ventricular (LV) diastolic function and glucose metabolism in individuals without previously diagnosed diabetes mellitus.Design: A cross-sectional population-based study.Setting: A university hospital.Subjects: Thirty-five men and women 56-58 years of age without previously diagnosed diabetes or heart disease.Main Outcome Measures: Left ventricular diastolic function assessed by pulsed Doppler tissue imaging and its relation to fasting plasma glucose, glucose postload and glycated haemoglobin. LV diastolic function was determined by measuring early diastolic filling peak velocity (Em wave cm s-1), late diastolic filling peak velocity (Am wave cm s-1) and their ratio Em/Am.Results: Peak Em velocity, peak Am velocity and their ratio Em/Am correlated with fasting plasma glucose (r=-0.42, P=0.01; r=0.47, P=0.04 and r=-0.53, P=0.001, respectively). There was a correlation between peak Em velocity, the ratio of Em/Am and glycated haemoglobin. LV diastolic function was also related to glucose postload.Conclusions: Left ventricular diastolic function is related to concentrations of fasting plasma glucose, glucose postload and glycated haemoglobin even below the threshold of diabetes. This indicates that glucose concentrations already in the upper end of the normal range has negative impact on cardiac function. [ABSTRACT FROM AUTHOR]

Analysis of heart rate variability (HRV) has been used in studies of autonomic function and risk assessment in different patient groups such as in patients with diabetes mellitus, after myocardial infarction (MI) and other cardiovascular disease. Ectopic beats can, however, interfere with HRV analysis and give erroneous results. We have therefore studied the impact of ectopic beats on HRV analysis and the ability of a filter algorithm to correct this. Power spectral analysis of synthetic data with an increasing proportion of ectopic beats and 24-h Holter recordings from 98 healthy subjects and 93 post MI patients was done with and without digital filtering and interpolation of errors in the data stream. The analysis of HRV was seriously hampered by less than 1% of ectopic beats. A filter algorithm based on detection and linear interpolation of ectopic beats and other noise in the data stream corrected effectively for this in the synthetic data employed. In the healthy subjects and the post MI patients, filtering markedly reduced the extra variability related to non-normal beats. The software could automatically analyse over one hundred 24-h files in one batch. HRV analysis should include filtering for ectopic beats even with a small number of such beats. It is possible to make a fast analysis automatically even in huge clinical series, which makes it possible to use the method both clinically and in epidemiological studies. [ABSTRACT FROM AUTHOR]

SUMMARY Aims Autonomic neuropathy is a serious diabetic complication, probably contributing to the death of many young people with Type 1 diabetes mellitus. It is often not diagnosed. Methods Patients with Type 1 diabetes from the Stockholm Diabetes Intervention Study were investigated with power spectral analysis (n = 88), heart rate and blood pressure reactions to tilting (n = 66), and heart rate variability during deep breathing (n = 70) a mean of 11.4 years after randomization to intensified conventional treatment (ICT) or standard treatment (ST), the treatment groups similar with regard to age, duration of diabetes and metabolic control at baseline (HbA1c 9.4 (1.3)%, mean (sd)). Blood glucose levels (mean of 29 HbA1c values) during the 10 years were lower in the patients from the ICT group (7.2 (0.6) vs. 8.3 (1.0)%, P = 0.001). Results Heart rate variability (HRV) in the high frequency range (P = 0.034), the expiration–inspiration ratio (P = 0.020), and the brake index during tilt (P = 0.044) were lower in the ST group, indicating more pronounced parasympathetic insufficiency. Systolic blood pressure fell by 10 (16) mmHg in the ST group, and by 2.5 (15) mmHg in the ICT group 8 min after rising from the supine to a 70° upright position (P = 0.034). A decreased autonomic function was associated with age and higher HbA1c. Conclusion Better autonomic nerve function is associated with lower HbA1c and lower age which were both the same in the intensively and the conventionally treatment groups at baseline. After a mean of 11.4 years autonomic function was better in the intensively treated group. [ABSTRACT FROM AUTHOR]

Background: Exercise capacity of patients with chronic heart failure (CHF) correlates poorly with estimates of cardiac function. Yet, it has been suggested that only patients without severely impaired cardiac output (CO) benefit from exercise training. Comparisons of different training models have not been made in the same study.Aims: To evaluate whether the response to different training models diverges according to the cardiac output response to exercise in patients with chronic heart failure.Methods: Sixteen CHF patients (63 +/- 11 years) with an ejection fraction of 30 +/- 11% underwent a baseline cardiopulmonary exercise test, right heart catheterization and leg muscle biopsy. Cardiac output (CO) response to exercise was defined as the ratio between CO increase and the increase in oxygen uptake (CO response index) during exercise. Patients were randomized into two training regimens, differing with regard to active muscle mass, i.e. whole body and one-legged exercise.Results: Baseline exercise capacity expressed as W kg-1 correlated with the CO response index (r = 0.51, P < 0.05). Exercise capacity on the cycle ergometer increased in both groups but more in the one-legged than in the two-legged training group (P < 0.05). The improvement in exercise capacity did not correlate with base-line exercise capacity. It correlated with CO response index in the one-legged (r = 0.75, P < 0.01) but not in the two-legged training group. CO response index correlated negatively with the pulmonary capillary wedge pressure at peak exercise (r = - 0.60, P < 0.05). The increase in leg muscle citrate synthase activity after training correlated negatively with the baseline CO response index (r = - 0. 50, P < 0.05).Conclusions: The improvement of exercise capacity after one-legged training correlates with the CO increase in relation to the O2 uptake before training. In patients with low CO response, individualization of the exercise regimen is needed and the benefits of training a limited muscle mass at a time deserve further study. [ABSTRACT FROM AUTHOR]

The aim of this study was to: (1) compare the usefulness, in clinical practice, of different echocardiographic methods of left ventricular (LV) function determination in patients with a recent thrombolytic-treated acute myocardial infarction (AMI); (2) compare these measurements with the reference method radionuclide imaging; and (3) evaluate the reproducibility of visual estimation of the LV ejection fraction (EF) and the use of the biplane method of discs (Simpson's rule) in clinical practice. Echocardiography and radionuclide imaging were performed within 2 hours of each another, 5 to 8 days after hospital admission. Ninety-six patients (70 men and 26 women) age 64 +/- 9 years (range 45 to 75) were studied. The echocardiographic study was performed by 2 experienced physicians, independently of each another. LV wall motion score index and visual estimation of the EF correlated best with the radionuclide EF (r = 0.72 and r = 0.71), thereafter simply counting the number of affected LV segments (r = 0.67) or atrioventricular plane measurements (r = 0.64). Simpson's rule had low correlation to the radionuclide EF (r = 0.45 to 0.51) and could not be used in approximately half of the patients due to poor identification of endocardial borders. The interobserver coefficient of variation for independent visual echocardiographic estimation of the EF was 10%, for Simpson's rule 18%, and for the radionuclide EF 5%. We conclude that the EF estimated from quantitative echocardiographic volume calculations (Simpson's rule) may differ substantially from radionuclide methods of measuring the EF. However, with experienced sonographers, the LV wall motion score index or visual estimation of the EF had reasonable agreement with the radionuclide EF in most of the patients. Atrioventricular plane measurement is an acceptable alternative. [ABSTRACT FROM AUTHOR]