Biomedical subjects

B Fiser

Publications and source records attributed to B Fiser.

At least 19 recordsLinked to original sources

PubMed2006

The short-term effect of water-pipe smoking on the baroreflex control of heart rate in normotensives.

UNLABELLED: The aim of this study is to analyse the acute effect of water-pipe smoking on heart rate, blood pressure and the baroreflex control of heart rate. SUBJECTS AND METHODS: Non-invasive continuous methods were used for investigating inter-beat interval (IBI; ms), systolic blood pressure (SBP; mm Hg), diastolic blood pressure (DBP; mm Hg), pulse pressure (PP; mm Hg), mean blood pressure (MBP; mm Hg); baroreflex sensitivity in ms/mm Hg (BRS) and baroreflex sensitivity in Hz/mm Hg (BRSf), were determined by spectral analysis, in 20 normotensive volunteers age of 27+/-6 years (mean+/-S.D.) who served as their own control. The measurements were taken twice. The first measurement was taken before the water-pipe smoking session (this is after >12 h of smoking cessation with a complete stopping of alcohol, coffee or tea consumption). The second measurement was taken during a 5 min period immediately after that session. (In the smoking session the volunteer smokes 5 g Maassel (fruit flavoured tobacco) for a period of 45 min). RESULTS: The inter-beat interval decreased (846+/-100 to 709+/-109 ms, p=0.0003), SBP increased (110+/-13 to 123+/-12 mm Hg, p=0.004), DBP increased (67+/-11 to 81+/-11 mm Hg, p=0.0002), PP decreased (43+/-10 to 41+/-9 mm Hg, p=0.46 ns), MBP increased (82+/-10 to 95+/-11 mm Hg, p=0.0001), BRS decreased (9.16+/-4 to 5.67+/-3 ms/mm Hg, p=0.003) and BRSf (0.013+/-0.005 to 0.011+/-0.004 Hz/mm Hg, p=0.3 ns). CONCLUSIONS: Water-pipe smoking induced a high increase in heart rate, SBP, DBP, MBP and markedly impaired BRS. All of those markers are known as risk factors in cardiovascular diseases, hence it is concluded that water-pipe smoking is not as harmless as is thought.

Adult↗

PubMed2006

[Medical device Task Force Monitor in diagnostics of syncope by means of head-up tilt table testing].

Head-up tilt table testing is used for diagnostics of vasovagal syncope. Beat-to-beat blood pressure recording and ECG monitoring is not sufficient for clarification of the syncope mechanisms in individual patients, however. That is why a Task Force Monitor was developed in Graz, Austria. In addition this device enables stroke volume recording by impedance method. Other advantages are calculations of cardiac output, beat-to-beat total peripheral resistance, heart rate variability and baroreflex sensitivity as well as activity ofsympathicus and parasympathicus assessment. These methods enable detailed hemodynamic analysis during the whole head-up tilt testing duration, the moment of syncope including.

Baroreflex↗

PubMed2005

Baroreflex sensitivity as an individual characteristic feature.

The reproducibility of baroreflex sensitivity (BRS in ms/mmHg; BRSf in mHz/mmHg) determined with respect to the coherence between the variability in systolic blood pressure (SBP) and inter-beat intervals (IBI) or heart rate (HR) was tested. SBP and IBI were recorded beat-to-beat for 5 min (Finapres, breathing at 0.33 Hz) in 116 subjects (aged 19-24 years) sitting at rest three times in periods of one week. BRS and BRSf was determined by a cross-spectral method in a frequency range of 0.067-0.133 Hz. Eight indices were evaluated: BRS(0.1 Hz) /BRSf(0.1 Hz) - the value at a frequency of 0.1 Hz; BRS(COHmax)/BRSf(COHmax) - the value at maximum coherence; BRS(Wcoh)/BRSf - weighted value with respect to coherence values in the whole frequency range; BRS(WPcoh)/BRS(WPcoh) - weighted value with respect to coherence for frequencies with coherence above 0.5. All indices revealed a lower intraindividual than interindividual variability (p<0.001). The individual mean values of BRS or BRSf correlated (p<0.001) with standard deviation of their individual values for all indices. Baroreflex sensitivity is an individual characteristic feature with the highest reproducibility at its low values in spite of its resting variation. Reproducibility is not influenced by modification of the spectral method used.

Adult↗

PubMed2005

Opportunity of detecting pre-hypertension: worldwide data on blood pressure overswinging.

Overswinging or CHAT (brief for Circadian Hyper-Amplitude-Tension), that is an excessive circadian variation in blood pressure (BP), has been associated with a large increase in cardiovascular disease risk, present even in the absence of an elevated BP itself. This usually asymptomatic condition is usually overlooked by current practice based on spot-checks, because to be diagnosed, measurements need to be taken around-the-clock, preferably for 7 days at the outset. Once diagnosed, however, a usual circadian BP pattern can be restored by means of certain non-pharmacologic or pharmacologic interventions timed appropriately. Thereby, it is possible to reduce the risk of cardiovascular morbidity and mortality, cerebral ischemic events and nephropathy in particular. For the preparation of guidelines regarding the diagnosis of BP disorders and for the institution of primary as well as secondary preventive measures, it is important to know what the incidence of CHAT is on a global basis. We found 191 cases of CHAT among 1602 mostly 7-day/24-h BP profiles, obtained from several centers in different countries participating in an ongoing project on the BIOsphere and the COSmos (BIOCOS). CHAT incidence is about the same between men and women, but it is diagnosed more often among patients with borderline hypertension or with glucose intolerance. It is also more common among MESOR-hypertensive than among MESOR-normotensive individuals. Priority should be given to the development of an unobtrusive and affordable device to automatically monitor BP and to analyze the data as-one-goes, so that cardiovascular disease risk can be prevented.

Adult↗

PubMed2005

Incidence of sudden cardiac death, myocardial infarction and far- and near-transyears.

We analyzed cycles with periods, tau, in the range of 0.8-2.0 years, characterizing, mostly during 1999-2003, the incidence of sudden cardiac death (SCD), according to the International Classification of Diseases, 10th revision (ICD10), code I46.1. In the tau range examined, only yearly components could be documented in time series from North Carolina, USA; Tbilisi, Georgia; and Hong Kong, in the latter two locations based on relatively short time series. By contrast, in Minnesota, USA, we found only a component with a longer than (= trans) yearly (transyearly) tau of 1.39 years; the 95% confidence interval (CI) of the tau extended from 1.17 to 1.61 years, falling into the category of transyears (defined as a tau and a 95% CI between 1.0 and 2.0 years, with the limits of the 95% CI of the spectral component's tau overlapping neither of these lengths). During the same span from 1999 to 2003 in Arkansas, USA, a component of about 1-year in length was present, and in addition, one with a tau of 1.69 year with a CI extending from 1.29 to 2.07 years, a far-transyear candidate, far-transyears being defined as having a tau with a CI between 1.20 and 2.0 year, with the CI overlapping neither of these lengths. In the Czech Republic, there was also a calendar-yearly tau and one of 1.76 years. In the latter two geographic/geomagnetic areas, the about-yearly and the longer cycles' amplitudes were of similar prominence. The taus are only candidate transyears; the 95% CIs of their taus overlap the 2-year length. When a series on SCD from 1994 to 2003 from the Czech Republic was analyzed, the 95% CI of the transyear's tau no longer overlapped the 2-year length. Transyears were also found in the Czech Republic for myocardial infarctions (MI), meeting the original transyear definition in both a shorter and a longer series. Moreover, in the 1994-2003 series on MI from the Czech Republic, a near-transyear was also found, meeting the definition of a period with a 95% CI overlapping neither precisely 1.0 year nor 1.2 years, along with a far-transyear, defined as a tau between 1.2 and 2.0 years, again with the 95% CI covering neither of these lengths. Herein, we discuss near- and far-transyears more generally in the light of their background in physics and the concept of reciprocal cyclicities.

Chronobiology Phenomena↗

PubMed2005

Age-dependent relationship between the carotid intima-media thickness, baroreflex sensitivity, and the inter-beat interval in normotensive and hypertensive subjects.

The interrelationship between baroreflex sensitivity expressed in ms/mm Hg (BRS) or in Hz/mm Hg (BRSf), carotid wall thickness (IMT), and age was investigated in hypertensive and normotensive subjects with respect to the mean inter-beat interval (IBI) and blood pressure (BP). BP monitoring was performed in 25 treated hypertensives (Hy; 47.4+/-9.2 years of age) and 23 normotensives (Norm; 44.5+/-8.1 years). IMT was measured by ultrasonography. BRS and BRSf were determined by the spectral method (five-minute non-invasive beat-to-beat recording of BP and IBI, Finapres, controlled breathing at a frequency of 0.33 Hz). Significant differences between Hy and Norm were detected in IMT (Hy: 0.624+/-0.183, Norm: 0.522+/-0.070 mm; p<0.01), BRS (Hy: 3.5+/-1.6, Norm: 5.7+/-2.3 ms/mm Hg; p<0.01), BRSf (Hy: 0.005+/-0.002, Norm: 0.009+/-0.004 Hz/mm Hg; p<0.01), systolic BP (Hy: 131+/-21, Norm: 116+/-17 mm Hg; p<0.01) and diastolic BP (Hy: 77+/-16, Norm: 64+/-12 mm Hg; p<0.01). A significant correlation was found between age and IMT (Norm: 0.523, p<0.05; Hy+Norm: 0.419, p<0.01), age and BRS (Norm: -0.596, p< 0.01; Hy+Norm: -0.496, p<0.01), age and BRSf (Norm: -0.555, p<0.01; Hy: -0.540, p <0.01; Hy+Norm: -0.627, p<0.01), age and IBI (Hy: 0.478, p<0.05), age and diastolic BP (Hy: -0.454, p<0.05), BRS and IMT (Hy+Norm: -0.327, p<0.05) and BRSf and IMT (Hy+Norm: -0.358, p<0.05). Hypertensive patients have increased IMT and decreased BRS and BRSf. The positive correlation between age and IMT and the negative correlation between age and BRS and BRSf are in agreement with the hypothesis that the age-dependent decrease of baroreflex sensitivity corresponds to the age-related structural changes of the carotid wall. Using two indices of baroreflex sensitivity, BRS and BRSf, we could show that baroreflex sensitivity in hypertensives is lower not only due to thickening of the carotid wall, but also due to aging.

Adult↗

PubMed2001

Near 10-year and longer periods modulate circadians: intersecting anti-aging and chronoastrobiological research.

Biological cycles with relatively long and some unusual periods in the range of the half-week, the half-year, years, or decades are being discovered. Their prior neglect constituted a confounder in aging and much other research, which then"flew blind" concerning the uncertainties associated with these cycles when they are not assessed. The resolution of more about 10-year and other cycles, some reported herein, replaces the admission of complete unpredictability, implied by using the label "secularity." Heretofore unaccounted-for variability becomes predictable insofar as it proves to be rhythmic and is mapped systematically to serve as a battery of useful reference values. About 10-year cycles in urinary 17-ketosteroid excretion and in heart rate and its variability, among others, are aligned with cycles of similar length in mortality from myocardial infarction. Associations accumulate between cycles of natural physical time structures, chronomes such as the 10.5-year (circadecennian) Schwabe and the 21-year (circavigintunennian) Hale cycles of solar activity, and chronomes in biota. There are about 50-year (circasemicentennian) cycles in mortality from stroke in Minnesota and in the Czech Republic and also in human morphology at birth, the latter result reducing the likelihood that these cycles are purely human made. Associations among large populations warrant long-term systematic coordinated sampling of natural physical and biological variables of interest for the design of countermeasures against already documented elevated risks of stroke, myocardial infarction, and other catastrophic diseases, notably in elderly adults. New findings will be introduced against the background of the documented value of mapping rhythms in medicine and gerontology. In both these fields, rhythms promise the seeming paradox of better care for less.

17-Ketosteroids↗

PubMed2000

Critical value of baroreflex sensitivity determined by spectral analysis in risk stratification after myocardial infarction.

The risk of cardiac death in patients after MI is predicted by a decreased baroreflex sensitivity (BRS). The critical value of BRS based on phenylephrine administration is 3 ms/mmHg. The aim of this study was to determine the critical value of BRS assessed by spectral analysis of spontaneous fluctuations in pulse intervals and blood pressure. Digital blood pressure was recorded noninvasively (3 min, controlled breathing 0.33 Hz) in 112 patients, 8-18 days after MI. Nine patients died during the first year after MI. BRS was determined as the gain between the spectrum of the variability of systolic blood pressure and the cross-spectrum between the variability of pulse intervals and systolic blood pressure. The gain at the frequency of 0.1 Hz was taken as the measure of BRS. Sensitivity, specificity, and the positive predictive value were calculated in the range of 1-10 ms/mmHg in steps of 1 ms/mmHg. The value of BRS above which sensitivity no longer increases and specificity decreases was taken as the optimal value. The critical value of BRS determined by spectral analysis was 3 ms/mmHg (sensitivity 77%; specificity 71%). In conclusion, the spectral critical value of BRS determined by spectral analysis of spontaneous fluctuations in pulse intervals and blood pressure corresponds to the value determined by the phenylephrine method.

Baroreflex↗

PubMed2000

The cosmos and CHAT, prompting blood pressure and heart rate monitoring for Dérer's week.

BACKGROUND: The effects of natural environmental factors upon health, documented in Minnesota, support the proposition of Bratislava's champions of the cosmos and of the biological week, gauged via circaseptan rhythms by the late Ladislav Dérer, whose "macro-rhythm" lasted "most frequently about 6 days". MAIN PURPOSE: To introduce 7-day monitoring of blood pressure and heart rate into routine practice. STARTING POINTS AND METHODS: Cosinor analysis on 7-day series determines (conventionally ignored) consistent blood pressure overswinging, i.e., circadian hyper-amplitude-tension (CHAT), a disease risk syndrome, whether it is associated with a normal average blood pressure or a high blood pressure. RESULTS: Summary of information understandable by the general population on the dynamics of blood pressure. CONCLUSIONS AND MEANING FOR PRACTICE AND THEORY: Space weather reports may prompt preventive measures. Caution dictates in any event monitoring blood pressure and heart rate for 7 days to attempt to prevent strokes, rather than to ignore the greatest yet detectable risk of catastrophic vascular disease, CHAT, a risk greater than old age or high blood pressure. (Tab. 1, Fig. 3, Ref. 31.)

Blood Pressure Monitoring, Ambulatory↗

PubMed2000

Baroreflex sensitivity determined by spectral method and heart rate variability, and two-years mortality in patients after myocardial infarction.

Sympathetic overactivity and low parasympathetic activity is an autonomic dysfunction (AD) which enhances cardiac mortality. In the present study, the impact of AD on the mortality in patients after myocardial infarction was evaluated. We examined 162 patients 7-21 days after myocardial infarction, 20 patients of whom died in the course of two years. Baroreflex sensitivity (BRS) was estimated by spectral analysis of spontaneous fluctuations of systolic blood pressure and cardiac intervals (Finapres, 5 min recording, controlled breathing 20/min). The heart rate variability was determined as SDNN index (mean of standard deviations of RR intervals for all 5-min segments of 24-hour ECG recordings). BRS < 3 ms/mm Hg and/or SDNN index < 30 ms were taken as markers of AD. The risk stratification was performed according to the number of the following standard risk factors of increased risk of cardiac mortality (SRF): ejection fraction < 40%, positive late potentials and the presence of ventricular extrasystoles > 10/h. No difference in mortality between patients with AD (4%) and without AD (4.5%) was found in 92 patients without SRF, the mortality in 6 patients with three SRF was 66.6%. Five of these patients had AD. Out of 64 patients with one or two SRF, 32 had AD. The mortality of patients without AD was 6.25% and 31.2% of those with AD (p<0.025). It is concluded that AD enhanced two-years mortality five fold in our patients with moderate risks.

Aged↗

PubMed1997

Meta-analyzed heart rate variability, exposure to geomagnetic storms, and the risk of ischemic heart disease.

The aim was to examine how heart rate variability (HRV) relates to the risk of ischemic heart disease (IHD) and may provide a means to assess effects of exposure to geomagnetic storms. In Stockholm, the 24-hour SD of hourly estimates of heart rate (HR) were obtained by Holter monitoring from 50 men who had had an acute myocardial infarction or had angina pectoris and compared to that of 50 clinically healthy men of similar age. In Tokyo, the HR 121 normotensives and 176 treated hypertensives was monitored. The incidence of IHD was recorded prospectively for 6 years. These results are aligned with those of a retrospective analysis of archived data on all crews of the Soyuz spacecraft for 1990-1994 focused on ECG from cosmonauts (47 male and 2 female) at times corresponding to geomagnetic storms. The results clearly indicate a decrease in HRV in association with IHD (20.5%, p=0.002 in Stockholm, 20.0%, p=0.04 in Tokyo). By comparison, the about 30% decrease (p=0.041) in rms SD of HR in cosmonauts studied during a geomagnetic storm as compared to cosmonauts monitored on quiet days adds supportive evidence to the proposition that exposure to geomagnetic disturbances increases cardiovascular disease risk.

Adult↗

PubMed1997

[Harvesting the heart for preparation of heart valve allografts].

Allograft heart valves (AHV) are believed to be optimal prosthetic material for surgical aortic valve and/or root replacement and an ideal valved conduit for repair of some complex congenital heart defects. At the University Hospital Motol AHV were clinically used since 1983 (annually no more than twenty were collected). 1991 the Paediatric Transplant Centre was established and was entrusted to organise cadaveric hearts harvesting and to introduce the standard technology of AHV processing and banking. The results of co-operation with other Transplants Centres, as well as with coroners and forensic medicine specialists in 1992-1995 are presented. For the AHV processing 274 cadaveric hearts were collected in the Czech and Slovak Republics, 32 of them (11.7%) came from routine post-mortem and 242 (88.3%) were retrieved from multiorgan harvesting, 14 hearts were excluded for technical reasons and another five for the seropositivity of the donor (three HBSAg, one HCV and one VDRL). Another 14 AHV were not suitable for clinical use because of a congenital lesion (bicuspid aortic valve) or acquired pathology found during the AHV processing (advanced atherosclerosis) or retrospectively diagnosed at donors post-mortem (in vivo undiagnosed malignancy). The technology of processing, cryopreservation and banking of AHV as well as the clinical use of the tissue will be discussed separately.

Cadaver↗

PubMed1997

[Preparation, storage, transportation and use of heart valves for allotransplantation].

UNLABELLED: Thanks to the co-operation with Czech and Slovak Transplant Centres and with some of the Departments of Pathology and Forensic Medicine 274 hearts were collected for allograft heart valves (AHV) processing during 1992-1995. The Cardiac surgeon dissected the aortic valve with the root and the pulmonary artery trunk with the valve. Tissues were antibiotically (ATB) sterilised in cultivation medium E 199 (24 hours at 37 degrees C). ATB concentrations (mg/ml): Cepharin 0.2, Azlocilin 0.2, Tobramycin 0.08 and Amphotericin B 0.1 for harvesting at post-mortem (P) or Miconazol 0.05 for sterile retrieval during multiorgan harvesting (MOH). After sterilisation AHV were stored at 4 degrees C. 49 AHV were infected even after ATB treatment-15 of 35 collected at P (43%) and 35 of 218 procured during MOH (16%)-(p < 0.01-ch2 test). After serological screening of the donor and microbiological testing the AHV were released for clinical use. Most AHV were programmed cooled to the temperature of liquid nitrogen (-196 degrees C), in which they were stored at the Allograft Heart Valves Cryobank. Cryoprotection was achieved by 10% dimethylsulphidoxide. CONCLUSION: A technology of harvesting, processing, storage and transportation of AHV, was introduced. It enabled the routine use in many cardiac surgical units. The AHV Cryobank was established. 131 AHV were used clinically between 1992 and 1995 (transportation as far as 1300 km). 108 AHV (82.4%) were used for repair of complex congenital heart defects, while 23 (17.6%) were used for aortic valve and/or root replacement.

Heart Valves↗

PubMed1997

Baroreflex sensitivity during psychological stress.

The aim of this study was to analyse the changes of baroreflex sensitivity (BRS) and their relation to changes of heart rate and blood pressure in medical students during moderate psychological stress brought about by oral examination. The changes of BRS during the stress were compared with the changes during light physical exercise. Thirty three students were examined 30 min before and 30 min after the exam. Thirty-nine students of control group were examined at rest and during light exercise. Blood pressure was noninvasively recorded by Penáz method at rate-controlled breathing (0.33 Hz). The BRS [ms/mm Hg] and BRSf [Hz/mm Hg] were calculated by spectral analysis of spontaneous fluctuations of blood pressure and inter-beat intervals (IBI). BRS before examination (7.12 ms/mm Hg) was significantly lower than after the oral exam (8.77 ms/mm Hg, p<0.05). The difference between BRS in the test group after the oral exam and the control group at rest (10.78 ms/mm Hg) was not significant. BRS during light exercise (7.44 ms/mm Hg) corresponded to the value during psychological stress. The values of BRSf did not change during psychological stress (before: 0.0182 Hz/mm Hg; after: 0.0182 Hz/mm Hg) and exercise (rest: 0.0158 Hz/mm Hg; exercise: 0.0144 Hz/mm Hg). Correlation between BRS or BRSf and blood pressure were not found. A significant negative correlation (r=-0.404, p<0.05) between BRSf and the increase of diastolic blood pressure during stress was observed. It is concluded that BRSf remained constant during psychological stress and exercise, and differed essentially from that in hypertensive subjects.

Adult↗

PubMed1996

[Non-invasive test for aortic compliance in man].

We determined the compliance of the aortic "Windkessel" using a non-invasive method. The occlusion of the lower extremities (5 min, 180 mm Hg) elicited reactive hyperemia. An abrupt change in pressure in the occluding cuffs from 180 to 60 mm Hg increased femoral blood flow (measured by pulsed Doppler) and decreased blood pressure (measured by Penaz continuous method). During abrupt decrease in blood pressure, the compliance was calculated as a ratio of the blood volume flowing out of the aorta via the femoral arteries to the decrease of blood pressure. The measurements were made repeatedly in eight healthy men, and in patients with essential hypertension (ten patients with essential hypertension, IInd degree-WHO without treatment and six patients with essential hypertension, IInd degree-WHO treated with slow released verapamil). Compliance in the first group was 1.18 +/- 0.25 ml. mm Hg-1, in the second 0.96 +/- 0.21 ml. mm Hg-1, and in the third group 0.90 +/- 0.11 ml. mm Hg-1. We found a negative correlation between compliance and arterial blood pressure. However the relative large scatter requires repeated measurements.

Adult↗

PubMed1996

[24-hour ambulatory monitoring of blood pressure in patients with essential hypertension: the effectiveness of enalapril therapy].

The aim of the present paper was to study 24-h blood pressure profile in twenty patients with essential hypertension (mild to moderate) before and after treatment with ACE inhibitor enalapril in one day dose in the morning (15.6 +/- 6.1 mg). 24-h ambulatory blood pressure monitoring was examined after 14 days of placebo administration and after one month of enalapril therapy. Enalapril treatment decreased systolic blood pressure of 11.3 mmHg during daytime and of 9.4 mmHg at night, diastolic blood pressure of 6.1 mmHg during daytime and 5.8 mmHg at night, all differences were significant in comparison to placebo (p < 0.01). The through-peak ratios were 63.2% for systolic blood pressure and 54.0% for diastolic blood pressure. We can conclude that enalapril treatment in one day morning dose is efficient to decrease blood pressure during 24-h span without altering the diurnal profile.

Adult↗

PubMed1993

[24-hour monitoring of blood pressure in patients with essential hypertension].

The aim of the study was to determine the efficiency of enalapril therapy during 24-hours blood pressure monitoring. A group of healthy subjects (C, n = 11), a group of patients with essential hypertension without therapy (EH, n = 9) and a group of patients with essential hypertension II (WHO) treated with enalapril (Acepril Lachema) in once a day doses (13.0 +/- 2.1 mg per kg) during at least 10 months (EH A, n = 8). In all groups of patients and healthy subjects 24-hours blood pressure measurement was provided using Accutracker II equipment. The mean values of systolic (SBP) and diastolic blood pressure (DBP) from 24-hours measurement (+/- SD) were in the group of healthy subjects C 121.38 +/- 10.49/74.79 +/- 7.88 mmHg, in the group EH 146.58 +/- 12.20/88.0 +/- 8.97 mmHg, in the group EH A 127.38 +/- 8.36/74.71 +/- 6.08 mmHg. The differences between the maximum and minimum mean blood pressure values during 24 hours (SBP/DBP) were in the group C 33/27 mmHg, EH 37/29 mmHg, EH A 29/21 mmHg. The smaller difference in SBP and DBP in EH A patients was significant in comparison to C and EH (t-test, p < 0.05). Cosinor analysis proved the results. From our results we can conclude that the Acepril therapy decreases blood pressure more during the day-hours then during night and it is preferable in connection to the risk of night hypotension with hypoxia.

Blood Pressure↗

PubMed1992

Pressure wave cardiography; cardiac diagnosis by means of noninvasive continuous blood pressure record.

The pulse pressure (PP) is proportional to the preceding interval (T) because of the restitution of contractility and the Starling mechanism, and is inversely proportional to the pre-preceding interval (T-1) because of potentiation of contractility. The aim of the present paper was to find if this relationship can be used for diagnostic purposes. Blood pressure was noninvasively and continuously recorded for 3 minutes (Penáz method), in 26 healthy subjects, in 13 patients with congestive heart failure (NYHA I,II) and sinusoidal rhythms and in 21 patients with atrial fibrillations. By means of multidimensional regression analysis the coefficient D[T] and D[T-1] were calculated in each subject. D[T] expresses the relative role of the preceding, D[T-1] of the pre-preceding interval. The correlation between PP and T was small in subjects with sinusoidal rhythms. Subjects with particular correlation coefficients between PP and T-1 higher than 0.5 were used for further analysis (18 controls, 7 patients). The difference between D[T-1] in controls (0.30 +/- 0.20) and in patients (0.48 +/- 0.19) was significant (Wilcoxon P less than 0.05). In subjects with atrial fibrillations both D[T] and D[T-1] were higher in decompensated patients (Wilcoxon P less than 0.05). The ratio D[T]/D[T-1] was higher in patients with mitral stenosis than in patients with ischaemic heart disease (t-test, P less than 0.05). The test can be usefully employed as a screening test in medical practice.

Atrial Fibrillation↗