Heart rate variability during incremental cycling exercise in healthy untrained young men.

BACKGROUND: Linear relationship between the increase of heart rate (HR) and the power output (PO) during sub-maximal exercise is well documented. However the study considering the effect of progressive increase of PO on the parameters of heart rate variability (HRV) remain scarce. AIM: This study investigated changes of the HRV time and spectral parameters in young, untrained men during incremental cycling exercise. METHODS: Fifteen young, untrained men aged 21 +/- 1.5 years participated in our study. Preliminary medical examination excluded any cardiovascular diseases. The examined individuals were cycling on the cycle ergometer (Monark 824E, Sweden) with constant frequency, amounting to 60 rev x min(-1). PO was increased by 30 W every 3 minutes. ECG was recorded via shortened limb lead I, using Dual BIO Amp (AD Instruments, Castle Hill, Australia) hardware and Power Lab (AD Instruments) software. Spectral analysis of HRV was based on the fast Fourier transformation (FFT). The time (HR, RMSSD) and spectral (LF, HF) parameters were analysed within 3 minutes time periods, before the exercise and on each level of the generated power output. RESULTS: The exercise was performed until the subjects reached 80% of the HR max expected for their age. This has occurred at the PO = 202 +/- 33 W (mean +/- SD). Mean HR in this group showed linear increase (p < 0.001) with power output (90 +/- 7 bt x min(-1) at 30 W vs. 166 +/- 11 bt x min(-1) at the power output of 202 +/- 33 W). Significant decrease of time parameters of the HRV (0 W vs. 202 +/- 33 W)--SDNN (p < 0.001) and RMSSD (p < 0.001) were observed in the analysed group. Spectral parameters of the HRV also presented significant reduction. Decreases of total power of the HRV spectrum (TP, p < 0.001), low frequency (LF, p < 0.01) and high frequency (HF, p < 0.01)) spectra as well as LF/HF ratio (p < 0.01) were noted. CONCLUSIONS: In the light of the present study, the applicability of the HRV power spectrum, with its present interpretation, to the assessment of the sympatho-vagal interaction during incremental exercise is indeed very questionable.

Cardiac syndrome X--autonomic system disorders.

BACKGROUND: The abnormal neural regulation of the heart is one of the most important pathogenesis of cardiac syndrome X (CSX). The aim the study was to evaluate changes in autonomic nervous system activity (ANS) in CSX patients. METHODS: Forty-two patients (age 46 +/- 9 years) with CSX and forty-two healthy volunteers (age 47 +/- 9 years) as a control group were included in the study. Function of ANS was estimated with non-invasive tests based on simple cardiovascular reflexes. RESULTS: In 50% of CSX patients was diminished response to parasympathetic stimulation in deep breathing test. In response to sympathetic stimulation (the changes in body position, hand grip test) was observed decreased 30/15 ratios. The cardiac autonomic activities were altered with parasympathetic withdrawal and/or sympathetic abnormality in patients with CSX. CONCLUSIONS: The population of CSX patients is heterogeneous with normal autonomic system (about 23% of population) and abnormal ANS activity (about 77% patients). In cardiac syndrome X patients selected tests of ANS indicated presence of disturbances in sympathetic-parasympathetic balance.

Effects of vagal pacing on food intake and body mass in pigs.

UNLABELLED: In obesity patients inexpensive, non-invasive, low risk treatment remains a holy grail. The purpose of this study was to evaluate effect of long term and low frequency vagal pacing on feeding behavior in pigs. METHODS: Two groups of animals were investigated, first control with sham operation and second group with microchip (MC) on both vagal nerves placed laparoscopically. In both groups EGG was performed before and after MC implantation. Parameters of stimulation were stable (amplitude 170 mV, frequency 1 Hz, impulse duration 170 ms). RESULTS: MC group demonstrated continuous decrease in body weight gain during 8 weeks of experiment at average of 3.73 +/- 0.5 vs. 4.83 +/- 1.1 (p < 0.05). Food intake also decreased in MC group and was 16.38 +/- 1.3 vs. control 17.5 +/- 1.7 kg/w (ns). EGG recording showed decreased percent normogastria in MC group 26.66 +/- 10 vs. 76.2 +/- 16 (p < 0.05) mostly at cost of tachygastria 62.3 +/- 15 vs. 35.4 +/- 16% of the recording time. CONCLUSION: MC vagal pacing mostly decreased body weight being without significant influence on food intake causing gastric dysrhythmia.

The effect of transcutaneous nerve stimulation on intraductal biliary pressure in post-cholecystectomy patients with T-drainage.

OBJECTIVE: To evaluate the effects of transcutaneous electrical nerve stimulation (TENS) on intraductal biliary pressure (IDP) in basal conditions and after intravenous morphine and oral meal stimulation. DESIGN AND METHODS: Fifteen patients (5 male, 10 female) aged 31-83 years (mean 61.5 +/- 13.7 years) with prior cholecystectomy and residual in situ T-tube were examined. Final radiographs excluded any organic abnormalities. The study consisted of three sessions. On the first day (session 1), after the initial manometric intraductal pressure was measured for 15 min, TENS (using a PRO-TENS pocket stimulator) was applied for 15 min. Measurement was continued for 15 min after termination of TENS. The measurement was performed using a water-perfused manometry system (Synectics Medical, Stockholm, Sweden) by a triple-channel manometric catheter inserted into the common bile duct through a T-drain. On the following day (session 2), the protocol was similar except that, after basal IDP measurement, morphine hydrochloride 0.08 mg/kg was injected intravenously 10 min before TENS. On the third day (session 3), after basal measurements were taken, patients were given a standard test meal and the IDP was recorded continuously for 45 min. To estimate the effects of the stimuli applied, absolute intraductal pressure changes were analysed. RESULTS: In session 1, TENS reduced basal IDP in all patients by a mean of 3.95 +/- 1.6 mmHg. In 13 patients, 15 min after cessation of TENS a further decrease in IDP was observed. In two patients, termination of TENS was followed by a rebound increase in IDP; however, it did not reach the initial value (mean total decrease 5.05 +/- 2.25 mmHg). In session 2, administration of morphine produced an evident increase in IDP in all subjects by 6.9 +/- 2.7 mmHg. TENS decreased IDP in 13 patients. In two patients, TENS initially failed to lower elevated pressure, but it appeared several minutes after the end of stimulation. In 13 patients, the final IDP values were lower than the baseline pressures. In session 3, after administration of a test meal, IDP decreased within 30-40 min by a mean of 4.89 +/- 1.29 mmHg. CONCLUSIONS: TENS decreased basal as well as elevated IDP in the majority of the T-drain patients studied. The effect of TENS persisted after its termination. Elevated IDP is believed to be responsible for pain in patients with sphincter of Oddi dysfunction (SOD). Therefore, we think that TENS can be used effectively and safely as an optional therapeutic method in the treatment of biliary dyskinesia.

[Autonomic nervous system function in cardiologic syndrome X]. / Funkcja ukladu autonomicznego w kardiologicznym zespole X.

Syndrome X is defined as typical angina pectoris, positive treadmill exercise test, negative intravenous ergonovine test and angiographically normal coronary arteries. The pathogenesis of his syndrome is still not known. Alteration of autonomic nervous control of cardiac function have been described in syndrome X. The population of SX patients is heterogeneous having subgroup with normal and low abnormal autonomic system activity which in 40% of patients had normal heart regulation of autonomic system and in 60% we can observed abnormal regulation. It may be a result of high tonic sympathetic driver or low parasympathetic activity.

Screening for prostate cancer in a population of South Poland--studies 2000.

According to the frequency of appearance, prostatic carcinoma is said to be the fourth new growth tumour in men in Poland. Course of prostatic cancer in early period is symptomless therefore the number of death because of the prostatic cancer is still being increased. The improvement of this situation in our country might be done by introducing the mass, screening studies. Since 1.09.2000 to 31.12.2000 a preventive programme of diagnosis prostatic gland diseases has been performed by the Department of Pathophysiology Medical College Jagiellonian University in Cracow. 8089 men 50-69 years old (mean 60.2 +/- 5.83) were investigated. In the first step, digital per rectum examination (DRE), serum PSA level determination, urine test and IPSS questionnaire were carried out. The abnormal results (an increase of PSA above 4 ng/ml and/or or a palpable nodule in the per rectum examination) allowed to select 284 patients, who in the second stage underwent transrectal ultrasonography (TRUS) and the biopsy. Presence of early prostatic carcinoma has been diagnosed and confirmed in 28 patients. The possibly tentative diagnosis of cancer was considered in 1383 patients. In the light of our results we must underline that these screening procedures seems to be important, especially respecting to the fact of possibility early diagnosis of prostatic cancer.

Circadian heart rate variability in patients with primary arterial hypertension.

INTRODUCTION: Abnormalities of autonomic nervous system function (ANS) exist in patients with hypertension and have been considered as one of the important factors in developing of essential hypertension. However the information about the effect of antihypertensive treatment (angiotensin-converting enzyme inhibitors--ACEI) on cardiac ANS activity is scarce. The main aim of our study was to evaluate circadian heart rate variability changes in primary hypertension treated with ACE inhibitors. METHODS: Fourteen patients with essential hypertension with night/day differences of mean blood pressure of more than 10% (dippers) aged 26 to 61 years (mean 52.9 +/- 9.2) and 14 healthy volunteers, 14 healthy volunteers were recruited and matched for age and gender. Ambulatory 24 hour arterial blood pressure measurement using HolCARD (Aspel, Poland) recorder with simultaneous ECG monitoring using the Mediarc-Premier IV Holter Monitoring System (DRG-International) undertaken in both groups of patients. The hypertensive patients were tested before and after one year of the enalapril treatment. The HRV analysis was performed according to a standard Fast Fourier Transformation (FFT). The time and spectral analysis parameters were compared within the examined groups of patients during day and night. RESULTS: The results obtained in the control group showed the great circadian fluctuations in sympathetic and parasympathetic activity. A simultaneous circadian HRV evaluation showed also significant increases in night RMSSD, TP, VLF, LF and HF mean values (p < 0.05) with significantly decreased night LF/HF ratio (p < 0.05) in comparison to the day time recordings. After one year of ACE inhibitors treatment, we noted the following circadian changes: Significant increase of RMSSD, pNN50 (p < 0.05), TP, VLF, LF and HF (p < 0.05) parameters with non-significant increases in LF/HF ratio during night recording. A comparison between daily HRV parameters, before and after 1 year of ACEI treatment, presented significant increases in pNN50 and RMSSD mean values (p = 0.01) and decreases in LF/HF ratio, with simultaneous withdrawal of spectral parameters. However, no significant changes in comparison of night HRV parameters before and after ACEI intake were observed. CONCLUSIONS: Our observations support an attenuation of night vagal activity as an important factor in the pathogenesis of essential hypertension. The lack of effect of ACEI treatment on circadian heart rate variability parameters in patients with essential hypertension, despite long-term normalisation of blood pressure, suggests persistent circadian cardiac autonomic dysfunction in the "dippers" subgroup of patients.

[Electrogastrography and manometry of the stomach in patients with disturbances of basic electrical rhythm]. / Elektrogastrografia a manometria zoladka u chorych z zaburzeniami podstawowego rytmu elektrycznego.

Electrogastrography (EGG) is the only non-invasive method for investigating the myoelectric activity of the stomach. The aim was to show the relations occurring between the electromyographic and manometric recordings during the normal and abnormal EGG rhythm. A simultaneous EGG recording and manometry were performed in 20 healthy people, in 26 patients with bradygastria (group I) and 21 with tachygastria (group II). In the control group, over 90% of the EGG recording time was in the range of normogastria. After a meal, there were observed a more than twofold increase in the EGG amplitude, an improvement in the recording stability with decrease in the dysarrhythmia percent, an increase in dominant frequency (DF) and a lowering in dominant frequency instability coefficient (DFIC). In groups I and II there was shown a considerable difference in the DF range, an increase in DFIC and the number of dysarrhythmia cases, the lack of correct increase in the amplitude and lowering in the average frequency of phasic contractions and motor indices (MI). Additionally in this group there was a fall in the amplitude of contractions without MMC, and this corroborates with weak contractile activity. There was a positive correlation between the EGG amplitude changes and amplitude of phasic contractions and MI and power ratios (PR) only in the phases I and II MMC. It suggests a relationship between the EGG amplitude and changes in the stomach position and its contraction activity. The lack of correlation between the average EGG frequencies of phasic contractions and the DF and DFIC values does not allowed to observe correlation between the frequency of the phasic contractions and EGG dominant frequency.

[Early diagnosis of orthostatic hypotension in idopathic Parkinson's disease]. / Wczesna diagnostyka niedocisnienia ortostatycznego w idiopatycznej chorobie Parkinsona.

Autonomic dysfunction in idiopathic Parkinson's disease (IPD) is common and occurs in 70% of patients. The aim of the study was to evaluate autonomic mechanisms regulating cardiovascular system during tilt up test in IPD patients. The examination was performed in 35 patients with IPD (26 male and 9 female, mean age 60 +/- 9) and matched with gender and age 35 controls subjects (healthy volunteers, mean age 59 +/- 9). Patients were divided into two groups: group I--early stage of disease (n = 20) and group II--advanced stage of the disease (n = 15). The tilt test in IPD patients and in the control group lasted 3 minutes. In both groups tilt test was performed with a head-up tilt position of 60 degrees (tilt table Manumed, Netherlands). In both groups 30:15 ratio were lower than in the control group 1.03 +/- 0.08, 0.97 +/- 0.09 v 1.23 +/- 0.1 respectively (p = 0.001). In the second group the heart-rate variability after the tilt test was lower 6.2 +/- 4/min than in the control group 10.2 +/- +/- 1.9/min and group I 8.8 +/- 4/min (p = 0.01). The decrease of the systolic pressure in response to the tilt test was the highest in group II (16 +/- 14 mmHg), in the control group 4 +/- 7 mmHg, in group I 13 +/- 11 mmHg (p = 0.001). Ortostatic hypotension in IPD occurs in 36% of patients in an early stage and in 47% of patients in an advanced stage of the disease. The use of the tilt test enables the early diagnosis of cardiovascular disturbances in IPD.