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Dive into the research topics where Per Bjerle is active.

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Featured researches published by Per Bjerle.


Scandinavian Journal of Plastic and Reconstructive Surgery and Hand Surgery | 1992

Factors that influence the incidence of brachial oedema after treatment of breast cancer

Knut Segerström; Per Bjerle; Sten Graffman; Åke Nyström

Six factors that may increase the likelihood of swelling of the arm after treatment of breast cancer were investigated in 136 patients who had undergone treatment. The highest incidence of oedema was among patients who had received radiotherapy in high doses with few fractions to the axilla (60%), and in patients with a history of one or more infections in the arm on the operated side (89%). Overweight, oblique surgical incision, infection in the arm, and radiotherapy correlated with arm swelling. The age of the patient and whether the operation had been done on the dominant or non-dominant side correlated less with the incidence of oedema.


Medicine and Science in Sports and Exercise | 2000

Cardiac autonomic imbalance in an overtrained athlete

Rikard Hedelin; Urban Wiklund; Per Bjerle; Karin Henriksson-Larsén

PURPOSE In order to investigate overtraining-related adaptations in the autonomic nervous system, cardiac autonomic activity was examined in a junior cross-country skier who presented with reduced performance in competitions, early breathlessness during training sessions, and accumulated central fatigue. METHODS Power spectral analysis of heart rate variability (HRV) was performed before, when overtrained (OT), and after recovery (Rec). RESULTS In the overtrained state, high frequency (HF) and total powers in the lying position were higher compared with before and after. In normalized units, the increased HF in OT was even more prominent and clearly higher than in any control subject, and it was reversed in Rec. Resting heart rate was slightly reduced in OT and returned to baseline in Rec. CONCLUSIONS The shift toward increased heart rate variability, particularly in the HF range, together with a reduced resting heart rate suggest a cardiac autonomic imbalance with extensive parasympathetic modulation in this athlete when overtrained.


Diabetic Medicine | 2003

Does the autonomic nervous system play a role in the development of insulin resistance? A study on heart rate variability in first‐degree relatives of Type 2 diabetes patients and control subjects

Stina Lindmark; Urban Wiklund; Per Bjerle; Jan W. Eriksson

Aims To investigate dysregulation of the autonomic nervous system as a potential mechanism for early insulin resistance in the development of Type 2 diabetes.


Medicine and Science in Sports and Exercise | 2001

Heart rate variability in athletes : relationship with central and peripheral performance.

Rikard Hedelin; Per Bjerle; Karin Henriksson-Larsén

PURPOSE To investigate relationships between heart rate variability (HRV) and peripheral and central performance measures, 17 cross-country (X-C) skiers and seven canoeists were studied before and after a training period of 7 months. METHODS For the skiers and canoeists respectively, leg and arm peak torque (Tq), time to peak torque (TiTq), and total work (Wrk) were measured in an isokinetic dynamometer. Maximal oxygen uptakes (VO(2max)) were obtained from treadmill tests. Power spectral analysis of HRV was performed on electrocardiographic recordings in the resting supine position and after a tilt to yield power in the low-frequency (0.04--0.15 Hz) and high-frequency (0.15--0.45 Hz) components of HRV. RESULTS The change in normalized LF-variability in standing (Delta LFnT) correlated (P < 0.01) with the changes in TiTq (r = 0.63), max lactate (r = -0.63), and VO(2max) (r = -0.53). The change in absolute LFT was inversely correlated with the change in Tq. Subjects who improved VO(2max) were characterized by consistently higher high-frequency and total HRV than subjects with deteriorated aerobic capacity (P < 0.05). CONCLUSION The results suggest that improved measures of both peripheral and central (aerobic) work capacities were associated with a reduction of low-frequency HRV in the tilted position. High-frequency and total HRV did not change in proportion with changes in muscle performance or aerobic capacity, but the ability to further improve VO(2max) with training in these already fit subjects seemed to depend on their average levels of these HRV measures, interpreted to reflect parasympathetic activity.


Journal of the American College of Cardiology | 1989

Reassessment of valve area determinations in mitral stenosis by the pressure half-time method: Impact of left ventricular stiffness and peak diastolic pressure difference

Kjell Karp; Dag Teien; Per Bjerle; Peter Eriksson

Estimation of the orifice area is of major importance in the timing of valve dilation or surgery in patients with mitral stenosis. Determination of the area has traditionally been accomplished at cardiac catheterization by the Gorlin equation. The valve area can also be estimated noninvasively with Doppler echocardiographic measurements of the pressure half-time, which is inversely proportional to the area. This method has gained widespread acceptance, but its accuracy has recently been questioned and factors other than reduction of orifice area appear to modify the pressure half-time. In the present study, the influence of left ventricular stiffness (defined as diastolic pressure rise per milliliter of mitral flow) and peak atrioventricular pressure difference on the pressure half-time was examined both in a hydraulic model and by review of data from 35 patients with mitral stenosis. Left ventricular stiffness less than 0.13 mm Hg/ml was considered normal. In the model study, the orifice area correlated only moderately with inverted pressure half-time (1/PHT) (r = 0.67). By multiple linear regression, inverted pressure half-time was shown to be dependent on valve area, chamber stiffness and peak pressure difference (R = 0.89), area and stiffness being most important (R = 0.85). In the clinical study, an increased ventricular stiffness was found in 22 of the 35 patients. The pressure half-time method overestimated the Gorlin-derived area by an average of 72% in these patients compared with only 10% in 13 patients with normal stiffness (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)


Journal of Hand Surgery (European Volume) | 1993

Arterial spasticity and cold intolerance in relation to time after digital replantation

Clas Backman; Åke Nyström; Per Bjerle

Cold induced arterial vasospasm was studied in ten patients with single digit replantation, by measuring finger systolic pressure at different finger temperatures. Each patient was examined three times; within 2 weeks of surgery, after 1 year and after 3 years. The replantations were performed using long arterial and venous grafts. Cold-related vasospasm is established during the first year after trauma, and thereafter seems to be persistent. It is concluded that the subjective cold intolerance, which affects all patients after digital amputation regardless of whether replantation is performed or not, is partly due to vasospasm. It is less pronounced in patients without pathological vasospasm in the replanted digit. Cold intolerance is likely to decrease during the first 2 years after replantation, but not to disappear completely.


Scandinavian Journal of Medicine & Science in Sports | 2000

Pre- and post-season heart rate variability in adolescent cross-country skiers

Rikard Hedelin; Urban Wiklund; Per Bjerle; Karin Henriksson-Larsén

To investigate the effects on cardiac autonomic control after a competitive cross‐country skiing season, 9 females and 8 males, 16–19 years old, performed tilt‐table heart rate variability (HRV) recordings and incremental treadmill tests before (August), and after (April the following year) the most intensive period of training and competition. Spectral analysis of HRV showed increased total variability at rest and reduced low frequency variability in the tilted position (LFtilt) at the second test (P<0.05). The female subgroup showed consistently higher high frequency (HF) and total heart rate variability than males. Total run time (RunT) increased from 18.5±1.9 min to 19.4±1.7 min (mean±SD) in the entire group (P<0.05), while VO2max only showed a non‐significant increase (0.05


European Journal of Obstetrics & Gynecology and Reproductive Biology | 1986

Bladder wall mechanics and micturition before and after subtotal and total hysterectomy

Othon Lalos; Per Bjerle

Twenty-two women were assigned at random to subtotal (n = 11) or total (n = 11) hysterectomy. The frequency of micturition was recorded and urodynamic investigation was performed before, and 6 weeks and 6 months after the operation. After hysterectomy the frequency of diurnal micturition decreased and the urethral conductance increased in all patients. After total hysterectomy an increased bladder volume was found. The two operative methods did not differ with respect to pre- and postoperative changes of urinary frequency or urodynamics. The bladder function was not altered by either operation.


Transplantation | 1997

Impact of autonomic neuropathy on circulatory instability during liver transplantation for familial amyloidotic polyneuropathy

Ole B. Suhr; Urban Wiklund; Lennart Eleborg; Yukio Ando; Christer Backman; Vera Birgersdotter; Per Bjerle; Bo Göran Ericzon; Bengt Johansson; Bert Ove Olofsson

BACKGROUND Circulatory instability with severe hypotension frequently complicates liver transplantation in patients with familial amyloidotic polyneuropathy. Autonomic dysfunction is found early in the course of the disease by analysis of beat-to-beat heart rate variability (HRV). The aim of the present study was to investigate the impact of autonomic neuropathy on intraoperative circulatory instability during liver transplantation for familial amyloidotic polyneuropathy. METHODS Twenty-two patients were evaluated at the Department of Medicine, Umea University Hospital, by spectral analysis of HRV and later received liver transplants at Huddinge University Hospital. The low-and high-frequency bands obtained by spectral analysis of HRV in the supine and upright positions, respectively, were used as representative of sympathetic and parasympathetic activity. Circulatory instability during transplantation was defined as a fall in systolic arterial blood pressure below 70 mmHg for more than 5 min during the preanhepatic phase. RESULTS Both arrhythmia preventing spectral analysis of HRV and a sympathetic variability peak below 2.5 mHz2 were significantly more common among patients with intraoperative circulatory instability (P=0.03 and 0. 004, respectively). A diminished increase in pulse rate when tilting the patients from the supine to the upright position was also more pronounced among patients with circulatory instability (P<0.05). CONCLUSIONS The majority of patients who will develop circulatory instability with a pronounced fall in arterial blood pressure can be identified by Poincare plots of R-R intervals and spectral analysis of HRV. A low sympathetic peak or arrhythmia precluding spectral analysis of HRV is significantly related to operative circulatory instability.


Acta Neurologica Scandinavica | 1989

Autonomic neuropathy in familial amyloidotic polyneuropathy

Urban Niklasson; Bert-Ove Olofsson; Per Bjerle

ABSTRACT— Familial amyloidotic polyneuropathy (FAP) is characterized by both sensimotor and autonomic dysfunction. Autonomic disturbance involving the gastrointestinal tract, the urinary bladder, the cardiac conduction system, and the peripheral circulation has been described. In this study simple, non‐invasive tests of autonomic function based on heart rate variability were applied to 12 patients with FAP and 12 healthy volunteers. The heart rate variation during normal breathing, deep breathing and during tilt from recumbent to standing position was measured. All tests showed significantly less heart rate variation in patients than in controls and the heart rate variation decreased with increasing severity of neurological disability, but the small number of patients in our study does not allow any further comparison between subgroups. Our study thus indicates impaired cardiovascular autonomic function in patients with FAP and we believe that these findings might also be of importance in other forms of systemic amyloidosis.

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