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Even the recent SPRINT trial showed that patients with symptomless or asymptomatic OH during hypertension treatment should not be viewed as a reason to down-titrate BP therapy even in the setting of a lower BP goal. This systematic review and meta-analysis showed adequate BP-lowering treatment decreases risk for OH. 9 Hajjar I. Postural blood pressure changes and orthostatic hypotension in the elderly patient: impact of antihypertensive medications. Keywords: Delayed orthostatic hypotension; postprandial hypotension; vasovagal syndrome; Orthostatic hypotension; carotid sinus syndrome EN Delayed orthostatic hypotension postprandial hypotension vasovagal syndrome Orthostatic hypotension carotid sinus syndrome 503 505 3 08/22/22 20220701 NES 220701 1. The most common hypotensive syndromes seen in older adults (65 years and older) are orthostatic hypotension (OH), postprandial hypotension (PPH), hypotension with carotid sinus syndrome (CSS), and vasovagal syncope type 1(VVS type 1). [Extracted from the article]

Sample entropy (SampEn) was reported to be useful in the assessment of the complexity of heart rate dynamics. Permutation entropy (PermEn) is a new measure based on the concept of order and was previously shown to be accurate for short, non-stationary datasets. The aim of the present study is to assess if SampEn and PermEn obtained from baseline recordings might differentiate patients with various outcomes of the head-up tilt test (HUTT). Time-domain heart rate variability (HRV) indices and several nonlinear parameters were calculated using 500 RR interval-long ECG recordings done before tilting in patients with a history suggesting vasovagal syncope. Groups of patients with so-called cardiodepressive vasovagal syncope (VVS_2) during HUTT and patients who did not faint during the test were compared. Two types of HUT tests were analyzed: with spontaneous (SB) or controlled breathing (CB). In our study, SampEn was higher in VVS_2 patients during SB, and PermEn was higher in VVS_2 patients during CB. Irrespective of the type of breathing during the test, SampEn and PermEn were similar in patients with the same type of reaction during HUTT. The use of several entropy-based parameters seems to be useful in HRV assessment in patients with vasovagal fainting.

This paper presents an application of Approximate Entropy (ApEn) and Sample Entropy (SampEn) in the analysis of heart rhythm, blood pressure and stroke volume for the diagnosis of vasovagal syndrome. The analyzed biosignals were recorded during positive passive tilt tests-HUTT(+). Signal changes and their entropy were compared in three main phases of the test: supine position, tilt, and pre-syncope, with special focus on the latter, which was analyzed in a sliding window of each signal. In some cases, ApEn and SampEn were equally useful for the assessment of signal complexity (p < 0.05 in corresponding calculations). The complexity of the signals was found to decrease in the pre-syncope phase (SampEn (RRI): 1.20-0.34, SampEn (sBP): 1.29-0.57, SampEn (dBP): 1.19-0.48, SampEn (SV): 1.62-0.91). The pattern of the SampEn (SV) decrease differs from the pattern of the SampEn (sBP), SampEn (dBP) and SampEn (RRI) decrease. For all signals, the lowest entropy values in the pre-syncope phase were observed at the moment when loss of consciousness occurred. [ABSTRACT FROM AUTHOR]

The paper presents an application of Transfer Entropy (TE) to the analysis of information transfer between biosignals (heart rate expressed as R-R intervals (RRI), blood pressure (sBP, dBP) and stroke volume (SV)) measured during head up tilt testing (HUTT) in patients with suspected vasovagal syndrome. The study group comprised of 80 patients who were divided into two groups: the HUTT(+) group consisting of 57 patients who developed syncope during the passive phase of the test and HUTT(−) group consisting of 23 patients who had a negative result of the passive phase and experienced syncope after provocation with nitroglycerin. In both groups the information transfer depends on the phase of the tilt test. In supine position the highest transfer occurred between driver RRI and other components. In upright position it is the driver sBP that plays the crucial role. The pre-syncope phase features the highest information transfer from driver SV to blood pressure components. In each group the comparisons of TE between different phases of HUT test showed significant differences for RRI and SV as drivers.

O teste de inclinação (TI) é muito utilizado para a investigação de síncopes e pré-síncopes, pois possibilita o diagnóstico de diferentes tipos de disautonomias. A principal causa de síncope é a Síndrome Vasovagal, cujo diagnóstico é o mais frequente entre as indicações de TI. O exame é utilizado há cerca de 20 anos, mas muitos médicos desconhecem a metodologia. São importantes a indicação apropriada, após exclusão de causas cardíacas de síncope, e a orientação do paciente para garantir a tranquilidade e a segurança do teste. Existem controvérsias na literatura sobre a capacidade diagnóstica e a confiabilidade dos resultados. Os estudos com protocolos diversos podem explicar a variabilidade dos resultados. Nesta revisão, são colocadas as indicações e a metodologia recomendadas pelas diretrizes, complicações, limitações e perspectivas desse exame.El test de inclinación (TI) es muy utilizado para la investigación de síncopes y presíncopes, pues posibilita el diagnóstico de diferentes tipos de disautonomías. La principal causa de síncope es el Síndrome Vasovagal, cuyo diagnóstico es el más frecuente entre las indicaciones de TI. EL examen es utilizado hace cerca de 20 años, pero muchos médicos desconocen la metodología. Son importantes la indicación apropiada, después de exclusión de causas cardíacas de síncope, y la orientación del paciente para garantizar la tranquilidad y la seguridad del test. Existen controversias en la literatura sobre la capacidad diagnóstica y la confiabilidad de los resultados. Los estudios con protocolos diversos pueden explicar la variabilidad de los resultados. En esta revisión, son colocadas las indicaciones y la metodología recomendadas por las directrices, complicaciones, limitaciones y perspectivas de ese examen.The head-up tilt test (HUTT) is widely used for investigation of syncope and presyncope, since it allows diagnosing different types of dysautonomia. The main cause of syncope is the vasovagal syndrome, the most common diagnosis among patients with HUTT indication. The test has been used for nearly 20 years, but many doctors are unaware of the methodology. After the cardiac causes of syncope are ruled out, the appropriate indication of the test and instructions to patients are important to ensure that the test will be carried out in a safe and relaxed manner. There are controversies in the literature over the diagnostic capacity and reliability of results. Studies with various protocols may explain the variability of results. This review describes the guidelines-recommended methodology and indications, complications, limitations and perspectives of this test.

The paper presents possible applications of entropy measures in analysis of biosignals recorded during head up tilt testing (HUTT) in patients with suspected vasovagal syndrome. The study group comprised 80 patients who developed syncope during HUTT (57 in the passive phase of the test (HUTT(+) group) and 23 who had negative result of passive phase and developed syncope after provocation with nitroglycerine (HUTT(−) group)). The paper focuses on assessment of monitored signals’ complexity (heart rate expressed as R-R intervals (RRI), blood pressure (sBP, dBP) and stroke volume (SV)) using various types of entropy measures (Sample Entropy (SE), Fuzzy Entropy (FE), Shannon Entropy (Sh), Conditional Entropy (CE), Permutation Entropy (PE)). Assessment of the complexity of signals in supine position indicated presence of significant differences between HUTT(+) versus HUTT(−) patients only for Conditional Entropy (CE(RRI)). Values of CE(RRI) higher than 0.7 indicate likelihood of a positive result of HUTT already at the passive phase. During tilting, in the pre-syncope phase, significant differences were found for: (SE(sBP), SE(dBP), FE(RRI), FE(sBP), FE(dBP), FE(SV), Sh(sBP), Sh(SV), CE(sBP), CE(dBP)). HUTT(+) patients demonstrated significant changes in signals’ complexity more frequently than HUTT(−) patients. When comparing entropy measurements done in the supine position with those during tilting, SV assessed in HUTT(+) patients was the only parameter for which all tested measures of entropy (SE(SV), FE(SV), Sh(SV), CE(SV), PE(SV)) showed significant differences.

Iodinated contrast media are of paramount importance in the field of modern interventional cardiology. Although iodinated contrast media have an overall good safety profile, severe or life-threatening reactions can also occur. Herein, we report the case of a 74-year-old female patient who presented with non-ST elevation myocardial infarction and underwent a successful percutaneous coronary intervention. Shortly after the procedure the patient developed the full-blown clinical picture of an iodinated contrast media adverse reaction that was timely recognized and treated. The two types of adverse reactions to iodinated contrast media during a percutaneous coronary intervention are being discussed. A high level of clinical suspicion is warranted to ensure prompt recognition and appropriate management. [ABSTRACT FROM AUTHOR]

Sample entropy (SampEn) was reported to be useful in the assessment of the complexity of heart rate dynamics. Permutation entropy (PermEn) is a new measure based on the concept of order and was previously shown to be accurate for short, non-stationary datasets. The aim of the present study is to assess if SampEn and PermEn obtained from baseline recordings might differentiate patients with various outcomes of the head-up tilt test (HUTT). Time-domain heart rate variability (HRV) indices and several nonlinear parameters were calculated using 500 RR interval-long ECG recordings done before tilting in patients with a history suggesting vasovagal syncope. Groups of patients with so-called cardiodepressive vasovagal syncope (VVS_2) during HUTT and patients who did not faint during the test were compared. Two types of HUT tests were analyzed: with spontaneous (SB) or controlled breathing (CB). In our study, SampEn was higher in VVS_2 patients during SB, and PermEn was higher in VVS_2 patients during CB. Irrespective of the type of breathing during the test, SampEn and PermEn were similar in patients with the same type of reaction during HUTT. The use of several entropy-based parameters seems to be useful in HRV assessment in patients with vasovagal fainting. [ABSTRACT FROM AUTHOR]

Background: The head-up tilt test (HUT) is widely used to investigate unexplained syncope; however, in clinical practice, it is long and sometimes not well tolerated. Objectives: To compare the sensitivity, specificity, accuracy, and patients' tolerance of a conventional and shortened HUT. Methods: Patients with a history of vasovagal syndrome (VVS) were randomized to a conventional HUT (group I) consisting of 20-minute passive tilt followed by 25 minutes after administration of sublingual isosorbide dinitrate (ISDN), or a shortened HUT (group II) where ISDN was given immediately after tilt and observed for 25 minutes. The control group consisted of age- and gender-matched subjects without VVS symptoms. A specific questionnaire to evaluate tolerance was applied. Results: Sixty patients (29 ± 10 years, 82% female) were included. In group I, 22/30 patients had a positive HUT compared to 21/30 in group II (73% vs 70%, P = 0.77). There was also no difference in the accuracy between the two protocols (63% vs 73%, P = 0.24). The time to positivity was shorter in group II (13.2 minutes vs 30 minutes, P < 0.001). Within the control group (n = 60), the frequency of false-positives was 47% and 23% for the conventional and shortened HUT, respectively (P = 0.058). After conventional HUT, 65.2% subjects reported that the test was too long compared to 25% subjects after the shortened HUT (P = 0.002). Conclusion: In this study, the HUT without passive phase was not inferior to the conventional HUT regarding sensitivity, specificity, and accuracy. Furthermore, the shortened ISDN-potentiated protocol allowed faster diagnosis and was better tolerated. (PACE 2012; 35:1005-1011) [ABSTRACT FROM AUTHOR]

Spectral analysis of heart rate variability (HRV) was used to assess changes in autonomic function before and during postural tilt in 28 syncopal patients: 14 (group A) with positive and 14 (group B) with negative tilting test, and 14 normal controls (group C). Frequency-domain measurements of the high (HF) and low (LF) frequency bands and the ratio LF/HF were derived from Holter recordings, computed by Fast Fourier analysis for 4-minute intervals immediately before tilt testing, immediately after tilting, and just before the end of the test. In group A, the mean values of LF and HF decreased slightly in response to tilting while the LF/HF ratio increased, though these changes were not statistically significant. All parameters showed a statistically significant increase just before the onset of syncope. In group B, there were no significant changes in the parameters measured throughout the test. In group C. there was an increase in the LF and LF/HF ratio and a decrease in the HF immediately after tilting. There were no further significant changes in any of the parameters during the test. Syncopal patients have a different pattern of response to the orthostatic stimulus, in that they do not show the increase in sympathetic tone observed in normal individuals immediately after tilting. In the patients with a positive tilt test, there is a shift in the balance of ANS activity towards the sympathetic system shortly before the onset of syncope. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the heart rate variability in patients with vasovagal syndrome (VVS). Heart rate variability was expressed as: (1) the standard deviation (SD) of the mean RR interval; and (2) the SD as a percentage of the mean RR interval (%SD). Heart rate variability was measured in VVS patients and compared with control individuals. Eighteen patients (mean age 50 ± 14 years) with a history of recurrent syncope and positive tilt testing were included in the study. Fifteen asymptomatic individuals (mean age 53 ± 13 years) with no history of syncope and negative tilt testing were used as a control group. The SD and %SD (39 ± 38 and 5 ± 4 msec) in the VVS group were statistically higher at the tenth minute of tilt testing than in the control group (20 ± 14 and 2.5 ± 1.8 msec, P = 0.03 and P < 0.05, respectively). The mean RR interval (mean heart rate) was shorter after the 15th minute of tilt testing in the VVS group than in the control group (RR-VVS 687 ± 136 msec, RR-control 801 ± 131 msec, P ± 0.05). It is concluded that heart rate variability, as expressed by the SD of the mean RR interval, and the SD as a percentage of the mean RR interval (%SD) are significantly higher in VVS patients than in control asymptomatic individuals. [ABSTRACT FROM AUTHOR]

Dual chamber pacing may sometimes be directly indicated for carotid sinus hypersensitivity, vasovagal syndrome, and certain cases of sinoatrial block and intermittent atrioventricular (AV) block, although AV conduction is dominantly normal. At times of normal AV conduction, competition between ventricular pacing and spontaneous ventricular depolarization may occur, with its adverse hemodynamic effects on ventricular function and unnecessary drainage of pacemaker battery energy. A new mode of stimulation is described, called automatic DDD mode, which functions in 'pseudo-AAI' mode during normal AV conduction and reverts to classical DDD function during episodes of AV blocks. Furthermore, during pseudo-AAI function, the pacemaker measures certain physiological parameters that serve to automatically program certain parameters used in DDD mode. Preliminary clinical evaluation has shown that this new mode functions satisfactorily. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the effectiveness of chronic medical treatment with oral propranolol and its influence on heart rate variability in patients with vasovagal syndrome. A spectral frequency domain analysis was used for the estimation of heart rate variability characteristics. Thirty-six patients, mean age 49 ± 17 years, with a history of recurrent syncope and positive tilt testing were involved in the study. All patients received oral propranolol (five patients also had a dual chamber inhibited DDI pacemaker implanted) for a mean time 12 ± 6 months. One patient complained of syncope during this follow-up. The tilt test repeated in 29 patients during follow-up was negative in 28. In 20 patients treatment was discontinued for 4 days and a new tilt test was then performed. Eleven of these 20 patients (55%) had a positive test (<0.001 compared with the group in which treatment was continued). In the group of 11 patients in whom the tilt test became positive again after medical treatment had been withdrawn (mean age 43 ± 20 years) and in 11 asymptomatic controls (mean age 52 ± 19 years), with no history of syncope and negative tilt testing, tile heart rate variability was assessed. The increase in the low frequency component from rest to the maximum value of heart rate variability during tilt testing was higher in the vasovagal group than in the controls (2.6 ± 1.2 vs 1.5 ± 07 = 0.02). The ratio between the increases in the sympathetic and parasympathetic components was also higher in the vasovagal group (1.7 ± 0.7 vs 1.0 ± 0.3 respectively = 0.01). These differences during tilt testing were eliminated after propranolol treatment. It is concluded that sympathetic activity is a predominant factor in the pathogenesis of vasovagal syndrome and that medical therapy with propranolol could be effective in vasovagal patients. [ABSTRACT FROM PUBLISHER]

The article presents a discussion on the significance of pacemaker implants to elderly patients with heart ailments specially those with bradyarrhytmias. Cardiac pacing is an electronic technology which helps patients acquire appropriate heart rates and maintain normal atrioventricular sequence. Information on the mechanism of a basic pacemaker is included.

Background A previous observational study suggested that, in syncopal elderly patients with vasovagal syndrome, a test using adenosine-5′-triphosphate (intravenous ATP 20 mg. 2 ml−1) could identify a subgroup of patients at high risk of severe cardioinhibitory response and guide the therapeutic strategy. To test one aspect of these results prospectively, we designed a small study focusing only on vasovagal patients with abnormal response to ATP testing. Methods Twenty patients hospitalized for syncope, which was considered to be vasovagal, and exhibiting an abnormal ATP test—defined by a longer than 10 s cardiac pause—were randomized to two groups: half to implan-tation with a dual-chamber pacemaker and half to usual medical care. All patients who were not hospitalized for recurrences were assessed every 6 months in the clinic or by telephone. Results At baseline, the randomized patient groups were similar in their demographic and health characteristics and in the results of their ATP tests, for example the mean cardiac pause (21·4±9·3 vs 15·9±3·7 s) and the mean interval between escape beats during the pause (7·29±4·2 vs 7·48±3·3 s). During a mean follow-up of 52 months, recurrences appeared in six of the 10 usual-care patients (range 0·2–29 months) but in none of the implanted patients (P<0·02). Conclusions This limited trial (1) supports the conclusion that patients with an abnormal ATP test who receive a dual-chamber pacemaker suffer fewer recurrences than those who are monitored only; and (2) consequently further supports the hypothesis that, among vasovagal patients, a cardiac pause of longer than 10 s in patients administered ATP identifies those at high risk of symptomatic vagal cardiac inhibition. [ABSTRACT FROM PUBLISHER]

Vasovagal Syndrome: ATP Test Reproducibility. Introduction: Adenosine-5'-triphosphate (ATP) provokes negative chronotropic and dromotropic vagal effects. In vasovagal syndrome, ATP test (20-mg IV bolus infusion) represents a promising technique for identifying patients at risk of severe cardioinhibitory response of vagal origin. The electrocardiographic and related symptom reproducibility of this descriptive test must be assessed. Methods and Results: In order to achieve this objective, ATP tests were performed twice in 80 patients (44 men, 36 women; mean age 72.3 ± 12.2 years) by using the recently published test procedure and criteria of positivity. The second test was repeated shortly after the initial test (mean: 7 days) in 43 patients and long-term (mean: 3.7 years) In 37 patients. The Initial ATP test provoked a cardiac pause > 10 seconds in 31 patients (39%) and a short cardiac pause (s 10 sec) or no pause in 49 patients (61 %). The electrocardiographic outcome was reproduced during the second ATP test in 36 patients (84%) of the short-term group and in 29 patients (78%) of the long-term group. Similarly, symptoms were reproduced in 38 patients (88%) of the short-term group and 29 patients (78%) of the long-term group, reflecting the severity of the electrocardiographic outcome. Conclusion: The negative chronotropic and dromotropic vagal effect of ATP can be reproduced short term and long term in 84% and 78% of patients, respectively. Associated symptoms were related to the severity of the electrocardiographic outcome. [ABSTRACT FROM AUTHOR]

The paper presents an application of Transfer Entropy (TE) to the analysis of information transfer between biosignals (heart rate expressed as R-R intervals (RRI), blood pressure (sBP, dBP) and stroke volume (SV)) measured during head up tilt testing (HUTT) in patients with suspected vasovagal syndrome. The study group comprised of 80 patients who were divided into two groups: the HUTT(+) group consisting of 57 patients who developed syncope during the passive phase of the test and HUTT(−) group consisting of 23 patients who had a negative result of the passive phase and experienced syncope after provocation with nitroglycerin. In both groups the information transfer depends on the phase of the tilt test. In supine position the highest transfer occurred between driver RRI and other components. In upright position it is the driver sBP that plays the crucial role. The pre-syncope phase features the highest information transfer from driver SV to blood pressure components. In each group the comparisons of TE between different phases of HUT test showed significant differences for RRI and SV as drivers. [ABSTRACT FROM AUTHOR]

The paper presents possible applications of entropy measures in analysis of biosignals recorded during head up tilt testing (HUTT) in patients with suspected vasovagal syndrome. The study group comprised 80 patients who developed syncope during HUTT (57 in the passive phase of the test (HUTT(+) group) and 23 who had negative result of passive phase and developed syncope after provocation with nitroglycerine (HUTT(−) group)). The paper focuses on assessment of monitored signals' complexity (heart rate expressed as R-R intervals (RRI), blood pressure (sBP, dBP) and stroke volume (SV)) using various types of entropy measures (Sample Entropy (SE), Fuzzy Entropy (FE), Shannon Entropy (Sh), Conditional Entropy (CE), Permutation Entropy (PE)). Assessment of the complexity of signals in supine position indicated presence of significant differences between HUTT(+) versus HUTT(−) patients only for Conditional Entropy (CE(RRI)). Values of CE(RRI) higher than 0.7 indicate likelihood of a positive result of HUTT already at the passive phase. During tilting, in the pre-syncope phase, significant differences were found for: (SE(sBP), SE(dBP), FE(RRI), FE(sBP), FE(dBP), FE(SV), Sh(sBP), Sh(SV), CE(sBP), CE(dBP)). HUTT(+) patients demonstrated significant changes in signals' complexity more frequently than HUTT(−) patients. When comparing entropy measurements done in the supine position with those during tilting, SV assessed in HUTT(+) patients was the only parameter for which all tested measures of entropy (SE(SV), FE(SV), Sh(SV), CE(SV), PE(SV)) showed significant differences. [ABSTRACT FROM AUTHOR]

Background: The purpose of this study was to evaluate the prevalence of syncope induced by head-up tilt test (HUTT) and the type of positive vasovagal response to the orthostatic stress in a relationship to the estimated phase of menstrual cycle (follicular phase, luteal phase) or menopause., Methods: We observed a cohort of 500 women at age 13-89 years (median of age 37.5), referred to HUTT. Phase of the menstrual cycle was determined on the basis of the usual length of menstrual cycle and the day of the cycle at the time of the study. We assumed that the length of the luteal phase is constant and it is 14 days., Results: In premenopausal patients, the occurrence of the mixed and cardioinhibitory response was significantly more frequent in comparison to postmenopausal women (48.8 vs. 35.1% and 19.7 vs. 12.4%, respectively; p < 0.00001), while the occurrence of the vasodepressive one was significantly less frequent (7.3% vs. 28.6%; p < 0.00001) in that group of patients. Women in follicular phase presented vasodepressive response during HUTT more often than woman in the luteal phase (10.0% vs. 4.1%, p < 0.00001)., Conclusions: Among women referred for HUTT, the prevalence of the vasovagal syndrome did not differ between those that were pre- and post-menopausal. Higher incidence of vasodepressive reaction in postmenopausal women was observed. Among the premenopausal women, the vasodepressive type of vasovagal syndrome occurred more often in follicular then in luteal phase.