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This study aimed to investigate the reliability of 1) the key parameters of cycling ergospirometry (maximum power output [Pmax] and oxygen uptake [V̇O2peak], ventilatory thresholds 1 [VT 1] and 2 [VT 2], and cycling efficiency [CE] and gross efficiency [GE]), 2) the commonly used parameters to quantify exhaustion (maximum heart rate [HFmax], respiratory quotient [RQmax], blood lactate concentration [BLAmax], and ratings of perceived exhaustion [RPEmax]), and 3) the kinetics of exercise induced gas exchange measurements (oxygen uptake [V̇O2], carbon dioxide output [V̇CO2], and minute ventilation [V̇E]) using the PowerCube-Ergo metabolic system in consideration of international statistical recommendations. 12 women and 12 men (28 ± 4 years; 23.2 ± 2.4 kg/m(2)) performed two cycling tests (20 watt/min) separated by one week. The reliability was calculated based on differences in means (t test and effect sizes), retest correlation (intraclass correlation coefficient [ICC]), and within-subject variation (standard error of measurement [SEM]). Of the key parameters of cycling ergospirometry, an excellent reliability (ICC ≥ 0.969; p = 0.000) and high accuracy (%SEM ≤ 4.6) were found for Pmax, V̇O2peak, and VT 1. Of the most commonly used parameters to quantify exhaustion, an excellent reliability (ICC = 0.922; p = 0.000) and high accuracy (%SEM = 1.0) existed only for HFmax. The gas exchange measurements (V̇O2, V̇CO2 und V̇E) of the PowerCube-Ergo were all excellently reliable (ICC ≥ 0,991; p = 0.000) and the accuracy of V̇O2 (SEM = 0.10 l/min) and V̇E (SEM = 3.13 l/min) fulfilled the quality guidance of exercise physiology laboratories. For future studies and practical purposes, the results are vital for the decision as to whether a difference between two tests represents a true intervention effect or just a measurement error and for the estimation of required sample sizes., (© Georg Thieme Verlag KG Stuttgart · New York.)

Dyspnoea is a common symptom of exercice intolerance. Tests performed at rest often leave the reason open. Cardiopulmonary exercise testing (CPET) is a tool for the qualitative and quantitative assessment of the cardio-circulatory, pulmonary and metabolic response to exercise. It is the gold-standard in the evaluation of dyspnoea and identifying its etiology (obstructive/restrictive lung disease, heart failure, physical fitness …). CPET is particularly useful, if previous evaluations including history, physical examination, ECG, pulmonary function testing (PFT), X-ray, blood tests, and blood gases do not lead to a decisive diagnosis. The measurement of peak oxygen consumption, carbon dioxide production, minute ventilation and heart rate provides substantial diagnostic and prognostic information in a wide variety of clinical settings. Interpreting CPET requires pathophysiological knowledge and can sometimes be challenging. An easy-to-use algorithm may provide a useful assistance for interpretation the results. In addition to its use as a diagnostic tool, CPET can be used to support sportsmen reaching their training goals and evaluate subject's ability to work.

This article describes an easy to use test equipment for measuring the isometric force in the ankle joints in dorsiflexion and plantar flexion. The combination of the test equipment for measuring the voluntary maximal isometric muscle force in the ankle joint, the surface electromyograms and the motion analysis of the measured leg allow an objective comparison of the strength of the muscular force between the left and right leg. It might be also used as a control setup during rehabilitation after surgical treatment or injuries.

The ankle is a frequent site of injury for dancers. The aim of the controlled study was to examine the proprioceptive and sensorimotor control of the ankle in a group of dancers in professional training and to compare it with persons unused to physical training. The purpose was to investigate whether dance training influences the torque ratio of plantar flexion to dorsiflexion (PF/DF) and the proprioceptive performance compared to controls. 42 dancers (31 f, 11 m) in professional training and 40 sex- and age-matched controls performed a isokinetic peak torque test, a passive angle-reproduction test (Biodex System 3), and a single-limb-standing test. The female dancers showed a significantly higher peak torque ratio PF/DF at 30 degrees/s. The difference between male dancers and the controls did not reach a significant level. The dancers did not demonstrate lower absolute errors in passive angle-reproduction (5 degrees and 25 degrees PF) than controls. In the single-limb-standing test, the dancers achieved significantly better results than controls. Dancers could profit from special training of the dorsiflexors. In view of the balance deficits, coordinative exercises should be integrated into school and recreational sports more frequently.

Examining gait characteristics in older adults enhances our understanding of movement control in this population and helps to better target preventive interventions. Walking is a highly automated, regular motor behavior that is mostly controlled by subcortical locomotor brain regions. With increasing age, walking requires higher levels of attention and thus more cortical involvement in motor control. This can affect gait regularity by increasing stride-to-stride variability that is characteristically high among fallers. A growing number of clinical gait analysis systems is now available to determine gait variability and thus the falling risk in older adults. Interventions targeting high gait variability in older adults need to consider basic principles of motor learning. Previously common and automatic gait patterns have to be relearned and again brought up to a highly automated level of motor control. Regular walking exercise, and particularly T'ai Chi with its emphasis on sequenced, slow, and highly controlled movements, might be helpful in this relearning process. Further research is needed to explore other interventions that could favorably affect stride-to-stride variability of older adults.

Background: Exercise training is recommended for patients with severe chronic obstructive pulmonary disease (COPD) to improve the endurance capacity. While many patients confined to bed are not able to run exercise training, we investigated the influence of a bedside passive-ergometry on ventilation in patients with severe COPD., Methods: In nine patients with severe COPD confined to bed (FEV1.0 0,94 +/- 0,18 l, IVC 2,3 +/- 0,8 l, Raw 0,91 +/- 0,13 kPa/l/s) we measured oxygen uptake O2, breathing frequency BF and minute ventilation E during rest, passive movement (30 revolutions per minute), additional active movement and maximal exercise. As a control group six healthy men were investigated during rest and passive movement., Results: During maximal exercise in COPD patients O2 peak reached 618 +/- 177 ml/min, BF 26 +/- 7,2/min and E max 24,1 +/- 5 l/min. In rest O2 was 311 +/- 56 ml/min (53 % O2 peak), BF 17,6 +/- 3,1/min and E 13,3 +/- 2,7 ml/min (55 % E max), while during passive movement O2 was increased to 369 +/- 88 (62 % O2 peak), BF to 19 +/- 5,3 and E to 16,4 +/- 4,1 (68 % E max). In contrast O2 in control subjects dropped from 377,5 +/- 38 in rest to 336 +/- 27 ml/min during passive action, BF from 14 +/- 2,1 to 12 +/- 2,4/min and E from 11,1 +/- 1,3 to 9,1 +/- 1 ml/min., Conclusions: In patients with severe COPD oxygen uptake, breathing frequency and minute ventilation increased not only during active, but even during passive movement of a bedside ergometer. With this method an exercise training is possible even in COPD patients confined to bed.

In patients that are in rehabilitation the physical ability is measured with stationary cycle ergometers. A new ergometer, that can be mounted easily to a bicycle, allows the mobile measurement independent of the location. The principle is based on the simultaneous measurement of chain force and chain velocity. One component of the chain force is measured, that is generated by the change of the chain's direction by pulleys. The velocity of the chain is measured by the rotational speed of one of the pulleys. The new ergometer is easy to attach and remove. The measured values are digitized, numerically processed and recorded. Through a GSM-Modem these data are transmitted to a remote central host computer and allow the control/evaluation of the patient's performance.

Background and Objective: The prognostic value of dobutamine stress echocardiography in patients with suspected or known coronary heart disease has not exactly been assessed. Purpose of the study was the assessment of the prognostic value of DSE regarding cardiac events, especially in patients with a normal DSE finding., Patients and Methods: 316 patients (168 men, 148 women, mean age 61 +/- 10 years), included in this follow-up study, underwent DSE between January 1994 and December 1996 to evaluate clinically suspected or known coronary heart disease. DSE was classified according to resting and stress echocardiography as either "normal-normal (NN)", "normal-ischemic (NI)", "abnormal-normal (AN)", "abnormal-ischemic (AI)" or "inconclusive (C)". Follow-up by telephone took place between June 1997 and April 1998. "Events" were survived myocardial infarction and death. "Interventions" were revascularisation procedures, either percutaneous transluminal coronary angioplasty (PTCA) with or without stenting or aortocoronary bypass surgery., Results: In 161 patients, DSE was NN, NI in 27 patients, AN in 55 patients, AI in 54 patients and C in 19 patients. Mean follow-up duration was 28 months. Events occurred in 23 patients: survived myocardial infarction in 10, death in 13 persons. Interventions were carried out in 50 patients: PTCA with or without stenting in 19, aortocoronary bypass surgery in 31 persons. The event rate was significantly lower in patients with DSE classified as NN (P = 0.03 by log-rank) than in other groups. The intervention rate was significantly lower in the NN-group (P = 0.0001 by log-rank) than in the other groups, too., Conclusion: Patients with a normal rest echocardiography and DSE had a good prognosis in a long-term follow-up study.

Using conventional methods (Riva-Rocci, oscillometric), non-invasive blood pressure measurements allow readings to be obtained only at discrete times, at intervals of at least one or two minutes. During exercise ECG recording, continuous blood pressure monitoring capable of detecting brief blood pressure changes is desirable. Our new approach is based on the known dependency of pulse wave velocity and blood pressure. The pulse transit time is derived from an ECG and a simultaneously recorded photoplethysmogram, and the blood pressure is computed using a linear model. In addition to the conventional ECG device, only a finger or ear sensor is required, so that the application of the method is quite easy. Results indicating dynamic blood pressure variations during an exercise ECG are presented.

Lumbar isokinetic strength and the influence of age, bodyweight and testing velocity in patients with chronic low back pain in comparison with persons without pain. Lumbar isokinetic strength parameters of 80 patients with chronic low back pain and 70 persons without pain were compared and the influence of age, bodyweight and testing velocity was evaluated. The patients with chronic low back pain showed less strength than the persons without pain. All parameters of extension discriminated between the two groups whereas only some of the flexion parameters did. The isokinetic strength of the lumbal extension muscles was higher than the strength of the flexion muscles. In patients with chronic low back pain, isokinetic strength of lumbar extension muscles was more reduced than the strength of flexion muscles in comparison with persons without pain. At 90 degrees/sec in comparison to 60 degrees/sec, lower extension forces, higher flexion forces and changed ratios of flexion and extension muscles were measured. Age had an influence only on women. There were no changes in ratios of flexion and extension muscles with increasing age. Bodyweight showed weak correlations with isokinetic flexion forces. The influence of different factors on isokinetic force varies between patients with chronic low back patients and healthy subjects.

Following a review of the literature on dynamometric and kinemetric measurement systems in tetrapods (part 1, 19), the selection criteria and construction of a gait analysis laboratory for small animals at the Department of Veterinary Surgery of the Ludwig-Maximilians-University of Munich is described. The system consists of three units: a treadmill with integrated forceplates, a 3D-video motion analysis system, and dedicated computer and system software. The value of the equipment is demonstrated by means of results of clinical gait examinations (part 2). An advantage of the Munich system is that measurements of all four limbs on the treadmill can be repeated continuously and simultaneously.

Problem: The interdependencies between movements of the thighs and the lumbar vertebral shape are of high practical interest. Which are the normals of this phenomenon?, Method: In an experiment on 107 volunteers without before known spinal disorders and complaints of back pain (47 f, 60 m, 17 a-30 a), the interdependencies between movements of the thighs in the sagittal and the lumbar back profile were analysed. Hip joint movements were provoked by a lift jack, elevating the feet to the volunteers, which sat on a bicycle chair. The hip joint flexion was measured by a Zebris CMS 50. The sagittal profile of the lower back was sensed by a comb of steel needles with low friction support., Results: At 30 degrees of hip flexion, 68% of the volunteers demonstrated a kyphotic, 17% a straight and 15% a lordotic lumbar shape. Starting at 90 degrees of hip flexion, "definitively kyphosating movements" of the lumbar motion segments occur. At the end of the motion, 89% of the volunteers had a kyphotic, 3% a straight and 8% a lordotic lumbar configuration. Each 2 degrees of additional hip joint flexion caudo-cranially one more lumbar motion segment is recruited for the definitive kyphosation of the lumbar spine., Conclusions: Instead of a "physiological shape of the lumbar spine" its "physiological function" or its "physiological interaction between shape und function" should be in the focus of future discussions. In the sitting, hip joint flexion leads to a coupled motion of the thighs, the pelvic girdle and the lumbar vertebral column with the consequence of a kyphosation of the lumbar back shape.

Unlabelled: In order to document sport specific skills, 23 athletes with functionally unstable ankle joints as well as 18 healthy volunteers were evaluated by performing a single leg jumping test. For external stabilization of the ankle an Aircast-Brace, a Ligafix-Air-Brace, a Malleoloc-Brace as well as a tape bandage were applied. There was no negative influence on the jumping performance of the tested stabilizing devices in the uninjured ankle joints. There was also no significant difference between the devices. For functional unstable ankle joints most of the devices showed significant improvement of jumping performance. The best results were achieved by the Aircast-Brace, followed by the Malleoloc-Brace, the Ligafix-Brace and the tape bandage. Again, there was no significant difference between these devices. While the reaction time showed no difference in all test situations, the time for stabilizing the ankle joint was significantly worse in those ankle joints without a brace., Clinical Relevance: For athletic activities, which are dominated by movement patterns comparable to the applied jumping test, the tested stabilizing devices seem to have no negative effect on sports specific capabilities.

The intracompartmental pressure in the anterior tibial compartment was documented under standardized conditions in 29 patients walking at a speed of 4.5 km/h, as well as heel-and-toe running at a speed of 8 km/h. All pressure curves were integrated and the resulting mean pressure was compared with the arithmetic mean pressure indicated in the literature. During walking, the difference between calculated and integrated pressures was between 80 and 140%. In the case of heel-and-toe running, the difference was between 80 and 165%. On the basis of these results, the calculation of the mean intracompartmental pressure recommended in the literature does not appear to be of any clinical relevance.

Single-lead VDD-pacing is an alternative to DDD-systems in patients with AV-block and normal sinus node function. Atrial sensing plays a central role in these pacemakers. AV-synchrony, incidence of atrial arrhythmias and the occurrence of sinus node disease were investigated in 108 patients with VDD-pacemakers followed over a mean period of 24.8 months after implantation. Determinants influencing the occurrence of atrial undersensing were especially focused on. Mean atrial potential and sensing threshold were reduced within the first 2 weeks after implantation (p < 0.01). Intermittent atrial undersensing occurred in 25.9% of patients and was observed in 82.1% of these patients within the first 2 weeks after implantation. Positioning the atrial dipole in the low right atrium showed a significantly higher incidence of atrial undersensing (42% in comparison to 24% in the other positions). In a multivariate analysis including intra- and postoperative measurements as well as characteristics of the pacemakers and leads, it was the only parameter significantly (p < 0.02) correlated to the occurrence of atrial undersensing. Atrial fibrillation was observed in 4.6% of patients, a sinus node disease became evident in 2.7% of patients; 92.6% of patients remained in the AV-synchronous mode. Intermittent atrial undersensing is common in single-lead VDD-pacemakers and difficult to provide during implantation. The atrial dipole should not be positioned in the low right atrium and highest atrial sensitivity should generally be programmed. Nevertheless, VDD-pacing achieves an AV-synchrony comparable to DDD-pacemakers.

Chronic functional instability of the lateral ankle may be difficult to distinguish from mechanical instability when radiological stress test reveal only small ligamentous defects. When a decision for or against surgical reconstruction of the ligaments has to be made it can be helpful to use additional information on joint function. Therefore, a prospective study of 65 patients (mean age 24.1 +/- 4.6 years) with long-standing chronic ankle instability was conducted to demonstrate that the dynamic measurement of plantar pressure distribution can identify patients with functional ankle instability. Plantar pressure patterns were measured during gait by means of a capacitive platform, the EMED-SF system. The impulses at eight points of the foot were calculated intraindividually and compared with those in a group of 100 healthy subjects. On the basis of clinical criteria alone, the two groups of patients were distinguished, 35 with functional instability and 30 with mechanical instability. The patients with functional instability showed significantly increased lateral loading of the unstable foot (P = 0.01), whereas the group with mechanical instability tended to walk more on the medial side of the unstable foot. This finding is explained by a deficit or peroneal strength during the stance phase, based on a proprioceptive deficit after trauma. The new technique provides additional information, which is relevant and sufficiently important to help in making decisions about the individual patient with chronic instability.

Dobutamine stress echocardiography having established itself as a sensitive method for diagnosing coronary heart disease, even in the absence of normative values, the physiological haemodynamics as well as the physiological values for global and regional left ventricular myocardial function were measured., Test Persons and Methods: 14 healthy subjects (ten men, four women; median age 25 [range 21-32] years) underwent dobutamine stress echocardiography according to an internationally practised dosage steps protocol (5-40 micrograms/kg/min with additional 0.5 mg atropine at 40 micrograms)., Results: Maximal infusion rate achieved a serum dobutamine level of 1.67 micrograms/ml with minimal quartiles; it did not influence serum electrolytes (especially potassium). Heart rate increased from 64 to 150/min (P < 0.0001), blood pressure from 111/66 to 158/88 mmHg (systolic: P < 0.0001; diastolic P < 0.001) and the double product of systolic pressure and heart rate from 6714 to 24571 (P < 0.001). While the end-diastolic volume index decreased from 50 to 37 ml/m2 (P < 0.05), the end-systolic volume index fell from 20 to 7 ml/m2 (P < 0.0001). Regional wall motion analysis indicated an increase in left ventricular circumferential contractility with little scatter., Conclusions: The usual protocol for dobutamine stress echocardiography is a sensible one, because the haemodynamic effect occurs already at low dosage and can then be increased significantly with further dosage steps. High serum dobutamine concentrations can be achieved without arrhythmogenic hypokalaemia. Volume index and ejection fraction are especially discriminatory variables. Quantitative analysis of wall motion is justified because of the low scatter of values.

Swimming differs from other forms of exercise due to its additional hydrostatic and thermal burden. It was investigated whether additional pathologic findings in comparison to history and standard exercise tests can be obtained by holter monitoring during swimming. Symptoms and exercise electrocardiogram were compared with the holter ECG during swimming in 125 patients divided into 3 groups with different diagnoses and severity of cardiac diseases. In a considerable percentage of patients ischemic changes and severe rhythm disturbances were found only during swimming with further diagnostic and therapeutic consequences, though patients with moderate and severe angina and with significant ischemic signs in the exercise test were excluded and mainly patients with slight or absent symptoms were evaluated predominantly. Thus, since swimming is a favorite leisure-time occupation also in patients with diseases of heart and circulation, holter monitoring during swimming is of diagnostic importance in the rehabilitation of these patients.

Regional wall motion abnormality is the best indicator for coronary ischemia. Myocardial wall motion is registrated by cardiokymography (CKG), a mechanocardiographic method. Because of the high incidence of artefacts, echocardiography and nuclear imaging technique have been preferred. Computer-assisted signal averaging CKG improves practicability and allows measurements during exercise testing. Exercise testing was performed in 54 patients with suspected ischemic heart disease without mitral or aortic valve dysfunction, myocardial infarction or prior cardiac surgery. The results of simultaneously recorded ECG and CKG were compared with coronary angiographic results. CKG sensitivity and specificity were higher than that of ECG (76 and 80% vs 71 and 52%). If diagnosis was based on pathological or nonpathological results of both CKG and ECG, sensitivity and negative predictive value increased to 87 and 83%, respectively. Sensitivity reached 93% when only one pathological result was required. CKG combined with signal-averaging techniques has advanced to become a specific and sensitive tool in the non-invasive diagnostic approach to ischemic heart disease.

The aim of this study was to evaluate the ventricular evoked response (VER) measured with unipolar fractally coated pacing leads for use with rate-responsive pacemakers. To this end, the morphology of the VER, its variation with pacing rate and various levels of physical loading, and the long-term stability of the signal were studied using the telemetric features of implantable pacemakers. Fractally coated electrodes were used in order to minimize the stimulation artefact, thus enabling a reliable unipolar measurement of the VER. The VER shows uniform basic morphology, and remains virtually unchanged after 3 months; moreover, frequency and load-dependent changes of VER morphology were identical for all patients. A special programming device has been developed to evaluate a rate adaptive algorithm for optimizing the pacing rate to the current loading situation, and was successfully tested in two patients. The algorithm was shown to be capable of calculating a heart rate adequate for haemodynamic demand.

Exercise echocardiography, a versatile, noninvasive diagnostic test of left ventricular wall motion performed at rest and under induced stress, enables the cardiologist to detect and assess coronary artery disease. Stress-induced ischemia is thereby expressed as left ventricular regional wall motion abnormality. By using various physical (bicycle or treadmill exercise) and pharmacological (dipyridamole, dobutamine, adenosine) stress inducers, the test provides information about the localization and extent of coronary artery disease in addition to detecting stress-induced coronary insufficiency. As regards diagnostic accuracy in detecting coronary artery disease, stress echocardiography is superior to exercise electrocardiography and, according to the available data, it is comparable to perfusion scintigraphic testing. Studies have demonstrated the clinical value of stress echocardiography in detecting residual stenosis after angioplasty, for diagnosing bypass dysfunction after heart surgery, for preoperative risk assessment in noncardiac surgeries, and for obtaining prognostic information, e.g., after myocardial infarction. Preliminary studies have shown that pharmacological exercise echocardiography is able to identify viable myocardium in the early phases after acute myocardial infarction. Furthermore, it is able to predict the functional success of revascularization in chronic regional left ventricular dysfunction. In addition to the wide range of diagnostic possibilities in coronary artery disease, other notable applications include stress testing for assessment of global left ventricular pump function in patients with aortic regurgitation or cardiomyopathy.

Anterior cruciate ligament (ACL) injuries are considered of high prevalence in sports medicine and are of socio-economical relevance. Indications for operative treatment and the ability for physical activity after ACL injuries are discussed controversially. Although it is known that the ACL has neurosensory functions, no test system has been developed which takes this biological function into account. The first goal of this study was to determine the neurosensory function after ACL reconstruction, and the second goal was to develop predictive markers for functional results after surgery. 20 healthy athletes (10 male, 10 female) (control group) and twenty ACL deficient patients (10 male, 10 female) (study group) were included in a prospective, controlled study. Electromyograms (EMG) were performed under defined load conditions of the knee. Important results of our study are: 1. Previously described parameters can be reproduced with EMG techniques. Their validity was proved. Typical contraction patterns (m. quadriceps, hamstrings, m. gastrocnemius) for defined load conditions can be recorded. 2. Statistically significant differences can be shown between the control group and the study group as well as between the two legs (injured/noninjured) of the same patient in the study group. 3. The results suggest that the diminished innervation of the m. biceps femoris and m. gastrocnemius in down-ramp-running as an important parameter for ACL deficiency. 4. Distinct differences of innervation patterns of the muscles, which stabilise the knee in downramp walking suggest that despite a subjective stability, altered load conditions may result. Innervation patterns seem to vary from individual to individual. 5. Concluding from our findings, we suggest that clinical methods should be developed to allow a patient-specific assessment of physical activity.

Free transplantation of the latissimus dorsi muscle has become the treatment of choice in extensive soft-tissue defects of the lower leg after trauma. However, neither the ability of the remaining muscles of the shoulder to compensate for the lost function nor the long-term effects of latissimus dorsi removal on the function of the shoulder have been objectively measured. Therefore, the postoperative shoulder function in 23 patients was compared after removal of the latissimus dorsi muscle with 23 control subjects. The evaluation included a questionnaire, physical examination, and instrumented muscle-testing (cybex system). No significant statistical differences in the function of the shoulders of all the patients and control subjects could be verified, with the exception that 16 patients exhibited weakness during isokinetic torque during extension of the shoulder in a 55 to 65 degree flexion (4.2 +/- 1.2%). The latissimus dorsi free flap can therefore be recommended as a procedure for soft-tissue coverage of extensive wounds resulting only in negligible loss of function and a slightly altered appearance of the shoulder-girdle.

Cardiopulmonary exercise testing (CPX) allows a non-invasive control of the cardiopulmonary exercise capacity. In this study, we wanted to investigate if the CPX can be securely, practicably, and accurately performed in patients with invasively documented coronary heart disease (CHD). Furthermore, we wanted to find out the clinical value of CPX in CHD diagnosis. The CPX measurements (symptom-limited; ramp program with 20 Watts increase/min; semi-supine position; continuous registration of the cardio-circulatory parameters (HR, RR, ECG), of the gas exchange parameters (O2, CO2) and of the ventilation) in 101 patients have shown that CPX is secure, accurate, and practicable. The day-to-day reproducibility is high (r > 0.8). The respiratory anaerobic threshold can be manually evaluated by means of the PET O2 criterion in 95% of the cases. The CCS-classification of angina pectoris could not accurately describe the cardiopulmonary exercise capacity as compared to the Weber-classification. The disadvantage of the Weber-classification is that it does not respect the age-, sex- and weight-dependent differences of the normal values. Our own data and results from the literature demonstrate that the anaerobic threshold, the maximum VO2 and the maximum O2-pulse are the more reduced the more coronary arteries are involved, the more reduced the left ventricular function is. But, nevertheless, the range of values shows large overlaps so that an exact differentiation, based upon these parameters, is not possible. Patients with similar functional results or degree of reduced exercise capacity have different morphological alterations. Most patients demonstrated typical ischemic cascade with anaerobic threshold, ST-segment alterations, angina pectoris and, finally, reduced max. VO2. In conclusion, CPX does not replace the traditional methods of non-invasive and invasive ischemia detection, but enables secure, practicable, and accurate measurements of the individual cardiopulmonary exercise capacity and the interaction between muscles, heart, circulation, and lungs. Possibly, CPX can be used in the near future for identifying CHD patients with low, medium or high risk.

The aim of heart transplantation is to improve survival and exercise capacity of patients with endstage heart failure. Fifteen patients (1 female, 14 male) with a mean age of 48 years (ranging from 25-62) underwent cardiopulmonary exercise testing (CPX) before heart transplantation. 10/15 patients showed an oxygen uptake of < 4 ml/min/kg (Weber E) at the anaerobic threshold and 5/15 an oxygen uptake between 5 and 8 ml/min/kg (Weber D), so that a severe respectively very severe limitation of exercise capacity was documented before transplantation. Up to now 9/15 patients underwent heart transplantation. Cardiopulmonary exercise test could be repeated in 7 of these 9 patients, 12 up to 22 weeks following operation. Exercise capacity improved from former Weber-class E to class B in 2/5 patients, to class C in 2/5 patients, and to class D in 1/5 patient. Both patients with a preoperative class D improved to class C. Thus, in all cardiac recipients exercise capacity increased, whereas normal values were not reached. The denervation of cardiac allografts leads to a higher heart rate at rest, a delayed increase and diminished slope of exercise response and reduced heart rates at maximal effort. In 17 heart transplant recipients (3 female, 14 male) with a mean age of 53 years (ranging from 25-62), we investigated the exercise capacity with respect to the abnormal rate regulation of the donor heart, which was quantified by comparing the corresponding rate regulation of the remaining part of recipient's atrium driven by the sinus mode.(ABSTRACT TRUNCATED AT 250 WORDS)

We analyzed 128 cardiopulmonary exercise tests (CPX), performed in normal subjects (n = 31), in patients with coronary artery disease (n = 41), with chronic heart failure before (n = 14) and after (n = 14) application of oral PDE-inhibitors and in patients with HIV-infection on a bicycle-ergometer in semi-supine position using a ramp-program (dependent on study-population with 15, 20 or 35 Watt/min increases) with respect to the ability to determine the respiratory anaerobic threshold non-invasively, using the main criteria described by Wasserman et al.: the V-slope-method according to Beaver, the increase of the ventilatory equivalent for O2 (VE/VO2), the increase of the end-tidal PO2 (PETO2) and the increase of the respiratory quotient (RQ) during exercise. In the different study-populations we calculated the detection rates of the AT for each criteria separately. The typical changes in the end-tidal PO2 (124/128 = 96.9%) and the V-slope-method (119/128 = 92.9%) were the most reliable parameters to detect the anaerobic threshold. The characteristic changes of the ventilatory equivalent for O2 (VE/VO2) and of the respiratory quotient (RQ) we found in 100/128 (= 78.1%) and in 107/128 (= 83.6%) of the tests respectively. 86/128 tests (67.2%) showed typical changes in all four mentioned criteria. In another 24/128 tests (19.8%) three of four criteria were fulfilled. Therefore, our investigations showed that in 110/128 cases (85.9%) the AT could be determined by typical changes by means of at least three of the four described parameters. In 15/128 (11.7%) tests only two of four criteria were fulfilled.(ABSTRACT TRUNCATED AT 250 WORDS)

In 42 patients with POAD in stage IIb the blood-flow in the common femoral artery and in the superficial femoral artery was measured before, 10 days after, 3 and 12 months after femoro-popliteal bypass surgery. Blood-flow was detected noninvasively using a multichannel ultrasound computer system (MAVISR). Simultaneously Doppler pressure, skin temperature and tcPO2-values were measured. Thereafter the patients had to undergo treadmill tests (painfree and maximal walking distance). Compared to healthy volunteers preoperative blood-flow was significantly (p < 0.001) reduced in the common femoral artery and in the superficial femoral artery. Postoperatively the blood-flow increased significantly (p < 0.001) in patients with an open bypass. This increase could still be demonstrated up to one year after bypass surgery. Surprisingly, a significant (p < 0.01) postoperative rise in blood-flow was also observed in the non-operated leg. Doppler pressure, tcPO2-values (calf) in the operated leg and walking distance increased significantly (p < 0.001). The MAVISR as a noninvasive procedure allows to check the further development of the bypass-function independently of subjective influences, because quantitative changes in blood-flow are documented.

During steady-state exercise the noninvasive measurement of cardiac output using CO2-rebreathing has been found to be reliable and reproducible. In contrast, reliability of cardiac output measurement during unsteady state exercise is unclear. The ability to determine cardiac output (CO) noninvasively during steady state and unsteady state exercise was assessed in nine healthy students aged 25.7 +/- 7.4 years. Two cycle ergometer exercise tests were performed, one maximal unsteady state test with 25 watts increment of workload per minute, and also one steady state test at 25, 50, and 75 percent of max. VO2. CO was measured using the equilibrium CO2-rebreathing technique during unloaded cycling in both tests, at 75 and 150 watts in the unsteady state test and at all workloads during steady state exercise. Mean max. VO2 was 31.4 +/- 5.9 ml/kg/min and mean VO2 at the anaerobic threshold 24.5 +/- 7.2 ml/kg/min, respectively. During unsteady state exercise the CO2/workload slope was linear (r = 0.973), as with steady state exercise (r = 0.976). There was no difference concerning the slopes of both curves, but the elevation of VO2 with unsteady state exercise was lower, compared to steady state (p < 0.005). The relationships of CO/VO2 during unsteady and steady state exercise were best expressed by linear equations: CO = 7.49 x VO2 + 2.35 (r = 0.866) and CO = 8.24 x VO2 + 1.4 (r = 0.852), respectively. Similar to VO2/workload, both regressions did not have different slopes, but did have different elevations (p < 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

The cardiopulmonary exercise testing (CPX) is a non-invasive method for the evaluation of the cardiopulmonary exercise capacity. Based upon the recent technical progress in gas analysers and personal computers today it is possible to perform CPX with acceptable time consumption, high practicability and high reproducibility of the results in many clinical areas. CPX is realized on a bike or on a treadmill. In bicycle CPX a ramp program (increase of x watts per minute) or a constant workload test (p.e. with 75% of the watts at anaerobic threshold) are performed. Furthermore, an estimation of the cardiac output using CO2-rebreathing method can be realized during a ramp program or a constant workload test. In this paper, also the CPX parameters of the ramp program, the constant workload test and the CO2-rebreathing method are defined and explained. The normal values of CPX are dependent of age, sex, body weight and exercise program. This should be kept in mind in interpreting the measured CPX data. Additionally, the performance of a routine CPX will be reported. Furthermore, the accuracy of the CPX parameters and the potential influences on the data will be discussed. Finally, problems during measurements and their analysis will be clarified.

The clinician who uses cardio-pulmonary exercise testing (CPX) systems relies on the technical informations from the device producers. In this paper, the practicability, the accuracy and the safety of four different, available CPX systems are compared in the clinical area, using clinically orientated criteria. The exercise tests were performed in healthy subjects, in patients with cardiac and/or pulmonary disease as well as in young or old people. The comparison study showed, that there were partially large differences in device design and measurement accuracy. Furthermore, our investigation demonstrated that beneath repetitive calibrations of the CPX systems a frequent validation of the devices by means of a metabolic simulator is necessary. Problems in calibration can be caused by an inadequate performance or by unclean calibration gases. Problems in validation can be due to incompatibility of the CPX device and the validator. The comparison study of the four different systems showed that in the future standards for CPX testing should be defined.

To describe the phenomenon of human movement by means of kinematic and kinetic measurements in a more objective manner, so-called integrated gait analysis systems have been developed. Although the commercially available equipment has already reached high technical levels, it does not play an important role in routine clinical applications. Due to this fact, the main arguments of the practitioners still address the practicability of the devices as well as the lack of meaningful software support for data assessment. The former concern has led to the integration of two KISTLER platforms beneath a treadmill belt in order to continuously capture 3D ground reaction force data. The latter one has prompted the development of an additional software kit, which statistically preprocesses the raw data set for further computations and which should prospectively allow a detailed analysis with artificial intelligence techniques. This new software becomes even more meaningful from the practitioner's point of view, because it may also be used as a stand alone unit for a preliminary assessment of gait patterns. The first part deals with the design of integrating two KISTLER platforms beneath the treadmill belt. A description of the analysis software follows, which removes noise, especially the influence of friction, from the raw data set. Thereby the 3D ground reaction force, which is originally caused by the patient while walking, is reconstructed. Preliminary results are presented. In the second part methods of automatically preprocessing the kinematic data set are focused upon.

The Jugendwerk Gailingen's rehabilitees with severe craniocerebral trauma placed in open employment include some 10% who work in construction, electric and metal-working industry occupations involving exposure to fall hazards, as a rule having returned to their previous occupations or following vocational training. During their rehabilitation, specific considerations have to be taken into account due to this hazard, both relative to work characterization and to rehabilitee remaining abilities and vocational assessment. Initially, the risk of falling must be identified, with subsequent estimation whether continuation of the hazard-generating activity will presumably be possible and/or justifiable. In the affirmative, this is followed by vocational assessment, which, beyond work tolerance and capacities, also deals with fall safety. The necessary strength, mobility, coordination, attention, concentration, and flexibility are assessed using the so-called Gailingen scaffold test. Although this test simulates but a fraction of possible work situations above ground and does look relatively harmless compared to real worklife, more than 100 rehabilitees have achieved successful, lasting integration in a variety of occupations which partly involve a rather high exposure to fall hazards, without any accidents having been reported at follow-up.

Multiplane transesophageal echocardiography is a new development in transducer technology, which allows by rotation of the transducer to obtain not only transverse and longitudinal planes but also all intermediate planes. Exterior control allows continuous rotation of the scanning plane from the conventional transverse plane, corresponding to 0 degree, to the longitudinal plane, corresponding to 90 degrees and further to a left-right inverted transverse plane, corresponding to 180 degrees. Although the echoscope tip, which houses the rotatable transducer, is slightly larger than conventional probes, in our clinical experience of well over 400 cases, intubation of the esophagus is not more difficult than with the mono- or biplane probe. In comparison with the biplane technique the adjustment of intermediate planes is easier and less unpleasant for the patient, since mechanical irritation due to sideward flexion of the probe is less often necessary. Plane rotation, effected by control buttons in the echoscope handle, takes eight seconds from 0 degree to 180 degrees. The probe incorporates a 5 MHz phased array transducer, which alternatively works at 3.7 MHz. Pulsed, continuous and color Doppler are also integrated. Multiplane transesophageal echocardiography was used to investigate several clinical questions. In 41 patients with aortic valve stenosis the valve area was determined by planimetry. The valve area was measured in an individually aligned short axis view (between 50 degrees and 70 degrees). A high correlation (r = 0.95; Y = 0.9 X + 0.1; p < 0.01) with invasively determined valve areas by the Gorlin formula was found.(ABSTRACT TRUNCATED AT 250 WORDS)

Stress echocardiography has recently gained increased importance as a method for assessment of left ventricular function. However, suboptimal image quality in some patients may limit use of this technique. In the present study, 10 patients with moderate image quality in the resting echocardiograms (apical 4-chamberview) were reinvestigated after administration of the intravenous transpulmonary saccharide-based left heart contrast agent SHU 508 A. Duration of contrast enhancement in the left ventricle determined by visual assessment was 135 s (SEE +/- 39) at rest and 112 s (+/- 24) during maximum exercise. On a scale ranging from O (no contrast) to 4 (excessively strong contrast) enhancement averaged 2.5 at rest and during exercise. The left ventricle was divided into three segments (septum, apex, lateral wall) and delineation of the endocardial border was assessed. Detection of the border improved significantly after contrast administration, especially at the lateral wall. Despite better visual assessment of the endocardial border, there was no improvement in automatic or semi-automatic contour recognition. No clinically significant side-effects were observed. Three patients reported a sensation of warmth at the injection site. In conclusion, intravenous administration of SHU 508 A improves visual detection of the left ventricular endocardial border in patients with suboptimal image quality and helps to achieve acceptable diagnostic accuracy with stress echocardiography in these patients.

Depending on the time spent in a space station, weightlessness causes varying changes to various organs and regulatory mechanisms of the human organism, among them the structures of the active and passive locomotor system. Experience has shown that regular physical activity using varying forms of training is necessary to keep astronauts and cosmonauts healthy, efficient and fit for work and to prepare them for a safe return to terrestrial conditions. One of the main tasks of physical activity is therefore to counteract the changes in the neuromuscular function, muscle strength, endurance and fatigability under conditions of weightlessness. So far, the diagnostics of these changes was limited to dynamometric measurements before and after space flights as no dynamometric method had been devised which was precise enough under conditions of weightlessness. The development and the introduction of the dynamoergometer Motomir is described against the background of previous results obtained by dynamometric, ergometric, morphometric, biochemical, histochemical and neuromuscular examinations before and after missions of varying duration under conditions of weightlessness. This device was used for the first valid and reproducible examinations of muscle strength and endurance aboard the space station Mir during the Austro-Russian space mission Austromir. The results of the examinations with this speed-controlled dynamometer and training device obtained during a short-term flight of 10 days and a long-term flight of 6 months are described and compared to previous results in the literature. Based on the existing training devices, training methods and training plans and the results of the Motomir Study, plans for devices and methodologies for future long-term space flights of up to 3 years' duration will be discussed. Finally, the possible use of a speed-controlled dynamometer and training device for rehabilitation on earth after injuries, surgery and immobilization of the active and passive locomotor system as well as in the bed-rest syndrome is being presented.

By means of a specific arterial vessel training--indoor or outdoor--it is in any case possible to improve the individual walking performance. In the first phase of the training there is an increase of the arterial maximal flow, which then remains constant and may even rapidly decline without further training. The continual increase can be explained through metabolic, hemorheologic, and possibly microcirculatoric changes (microbiopsy studies, not yet published). At the moment it is only Germany where you can find the complete offer of all different vessel training. In Austria there is only the indoor training which works at the moment. The different German health-insurance pay the training-programs, the criteria for the education of "the vessel-trainer" are established by the health-insurance, by the "Deutsche Gesellschaft für Angiologie" and the "Deutsche Gesellschaft für Gefässsport (vessel training)". The vessel trainer has to achieve his diploma via the "A" and "coronar certificate". In Austria there are no obligatory criteria for this education--neither for the coronary nor for the vessel training--there is no observation of the education and no payment-system.

The value of stress echocardiography in the routine diagnosis of coronary heart disease was assessed in 100 consecutive patients (22 women, 78 men; mean age 57 [32-83] years) scheduled for coronary angiography because of suspected angina. Exercise consisted of bicycle ergometry (n = 50), on the one hand, simulated exercise with transoesophageal atrial stimulation (n = 16), dipyridamole (n = 33) and dobutamine (n = 33) infusions, on the other. 91 patients were successfully tested by at least one of these procedures, while exercise electrocardiography was successfully employed in only 78 (P < 0.05). Stress echocardiography had a greater sensitivity than exercise electrocardiography (90% vs 78%) and specificity (90% vs 73%). Semiquantitative measurement of wall movement distinguished patients without functionally effective stenosis from those with single or multiple vessel disease (P < 0.001). Stress echocardiography thus makes it possible in most cases to demonstrate or exclude functionally significant coronary artery stenoses.

The analysis of heart rate variability is supposed to be a marker of autonomic cardiac activity and is used for risk stratification of post-infarction patients. Analysis of heart rate variability in the frequency domain may permit a differentiation of vagal and sympathetic control; for such analyses only short time intervals characterized by a steady-state autonomic balance can be used. Yet, it is unclear whether single determinations of heart rate variability indices derived from short time intervals yield reproducible results. Therefore, the reproducibility of heart rate variability indices was studied with weekly measurements in 10 healthy volunteers under the following defined conditions: 13 min supine rest, 10 min standing, 13 min sitting, and 15 min cycle ergometry followed by a 14 min recovery period. Heart rate variability was determined in the frequency domain (fast Fourier transformation) and in the time domain. The reproducibility was estimated by the coefficient of variation (CV). Additionally, the reproducibility of heart rate, blood pressure, and the expiratory-inspiratory ratio of heart rate was determined. The reproducibility of the frequency domain indices (36.6-74.9% CV) and of the time domain indices (19.6-32.8% CV) was considerably worse than that of heart rate (5.2-8.2% CV), blood pressure (5.1-8.2% CV) and the expiratory-inspiratory ratio of heart rate (4.6% CV). The reproducibility of heart rate variability indices was not improved by orthostatic or ergometric challenge. This poor reproducibility does not permit a reliable interpretation of heart rate variability on the basis of single measurements in healthy volunteers. Given the wide range and scatter of the measured parameters, the diagnostic and prognostic value of heart rate variability indices derived from short recording periods appears questionable.

The results of a multicenter clinical study involving patients receiving the first ANS controlled rate adaptive pacemaker are presented. In the patients with primary or secondary chronotropic insufficiency, it is possible to reestablish the closed loop control system that includes the baroreceptors, the medulla oblongata, the cardiac output and the mean arterial blood pressure. This system serves to keep the blood pressure constant in the face of changing demands on the circulation. Utilizing intracardiac impedance measurements, the myocardial contractility can be determined, which contains information about the current sympathetic tone, and thus represents an excellent physiological input for a rate adaptive mechanism. The results presented are taken from a study population of over 200 patients. The objective evaluation of this new approach was performed echocardiographically, by ergometry and 24-hour Holter monitoring.

Problem: The setting of an exercise pulse rate has become established in particular in the field of post-infarction rehabilitation. The conditions associated with its establishment, however, vary considerably. As a rule, no differentiation is made for the variations in the muscular work done., Own Studies: Follow-up examinations in 29 post-infarction patients showed that the recommended exercise pulse rate was an average of 10 to 20 beats lower than that established in our office under ergometric conditions. Loading-control via respiration, monitored by lactate measurement, in contrast, has proved superior in our patients, since the respiration is perceived continuously and directly by the patient himself, and is largely independent of the type of exercise involved., Conclusions: Control of physical exercise (loading) via the respiration would appear superior to that by the measurement of the pulse rate. The setting of an exercise pulse rate only if it can be monitored reliably and continuously with the aid of a measuring device.