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1.
Medicine (Baltimore) ; 99(11): e19510, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32176097

RESUMO

Performing a head-up tilt test can be of great value for the diagnosis of vasovagal syncope. The European Society of Cardiology recommends a drug challenge phase duration of 15 to 20 minutes, with either Isoprenaline or Nitroglycerin administration.We sought to investigate the outcome of a ten-minute active phase with Nitroglycerin in patients suspected of vasovagal syncope and determine the percentage of loss in the positivity rate, using this short duration approach.We consecutively enrolled patients presenting with syncope undergoing the head-up tilt test (HUTT), with a clinical suspicion of vasovagal syncope between the years 2009 to 2019. The HUTT consisted of 2 successive phases: passive and active. During the passive phase, the patients were tilted at 70° for 20 minutes. If negative, the test was continued after administration of 0.4 mg sublingual Nitroglycerin. Applying the (VASIS) Vasovagal Syncope International Study classification of the vasovagal syncope international study and comparing for age and gender, positive responses were categorized into 3 types.A number of 306 patients (age = 43.5 +/-20.3; male = 140 [45.7%]) with suspected vasovagal syncope, undergoing HUTT, were enrolled in the years of 2009 to 2019. Of those, 245 (80.2%) presented a positive test, with 200 patients (82.0%) during the being positive during the active phase of the test. The results were as follows: 116 subjects (47.2%) presented with a mixed response (VASIS I), 52 (21.3%) showed a cardio inhibitory response (VASIS II), and 77 (31.5%) displayed a vasodepressor response (VASIS III). We found no relationship between the type of syncope with neither gender, nor age of the patient. Three minutes represented the median time to positivity, after Nitroglycerine administration. The time distribution showed a peak incidence appearing between minutes 3 and 5, ranging from 1 to 20 minutes. Only 3 patients tested positive after minute 10.Shortening the active phase to 10 minutes would result in a positivity rate loss of 1.5%.


Assuntos
Nitroglicerina/administração & dosagem , Síncope Vasovagal/diagnóstico , Teste da Mesa Inclinada , Vasodilatadores/administração & dosagem , Administração Sublingual , Adulto , Esquema de Medicação , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Fatores de Tempo
2.
Kardiologiia ; 59(11): 31-38, 2019 Dec 11.
Artigo em Russo | MEDLINE | ID: mdl-31849297

RESUMO

BACKGROUND: The direction of changes in hemodynamic parameters during the tilt test (TT) nin individuals with history of vasovagal syncope (VVS) is a subject of discussion. OBJECTIVE: to study changes of volume-impedance hemodynamic indicators in the process of tilt test in somatically healthy young men with history of VVS. MATERIALS AND METHODS: A total of 102 men aged 18-30 years were divided into 4 groups, taking into account the specific features of fainting history and response to TT. Persons of group 1 (n=14) had history of VVS and positive response to TT (syncope). Subjects of group 2 (n=14) had history of VVS and a pattern of postural tachycardia without fainting during TT. Persons of group 3 (n=42) had history of VVS and negative response to TT. Subjects of group 4 (n=32) had no history of VVS and negative response to TT. During TT, we studied dynamics of some indicators, including cardiac output (CO) and total peripheral vascular resistance (TPVR). RESULTS: In individuals of all groups in the initial horizontal phase of TT values of CO and TPVR corresponded to the norm. Subjects of group 1 had significantly lower CO compared with subjects of groups 2, 3, 4 (p<0.05, p<0.01, p<0.05, respectively). Values of TPVR in subjects of group 1 were significantly higher than in subjects of groups 2, 3, 4 (p<0.05; p<0.05; p<0.05, respectively). In response to orthostasis CO values increased in groups 1, 2, 4 (by 18%, 10%, 5%, respectively) and did not change in group 3; TPVR values decreased in groups 1, 2 (by 8%, 0.5%, respectively), and increased in groups 3, 4 (by 8%, 4% respectively). In the final horizontal phase of TT, CO values in group 1 were significantly lower than in groups 3, 4 (p<0.05), while TPVR values did not significantly differ between all groups (p>0.05). CONCLUSIONS: In tilt-positive and tilt-negative subjects with history of VVS, standardized postural stress leads to unidirectional changes in cardiac output, but to multidirectional changes in total peripheral vascular resistance.


Assuntos
Síncope Vasovagal , Adolescente , Adulto , Impedância Elétrica , Hemodinâmica , Humanos , Masculino , Teste da Mesa Inclinada , Resistência Vascular , Adulto Jovem
3.
Medicine (Baltimore) ; 98(43): e17600, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31651868

RESUMO

BACKGROUND: Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a complex condition with no reliable diagnostic biomarkers. Studies have shown evidence of autonomic dysfunction in patients with ME/CFS, but results have been equivocal. Heart rate (HR) parameters can reflect changes in autonomic function in healthy individuals; however, this has not been thoroughly evaluated in ME/CFS. METHODS: A systematic database search for case-control literature was performed. Meta-analysis was performed to determine differences in HR parameters between ME/CFS patients and controls. RESULTS: Sixty-four articles were included in the systematic review. HR parameters assessed in ME/CFS patients and controls were grouped into ten categories: resting HR (RHR), maximal HR (HRmax), HR during submaximal exercise, HR response to head-up tilt testing (HRtilt), resting HR variability (HRVrest), HR variability during head-up tilt testing (HRVtilt), orthostatic HR response (HROR), HR during mental task(s) (HRmentaltask), daily average HR (HRdailyaverage), and HR recovery (HRR) Meta-analysis revealed RHR (MD ±â€Š95% CI = 4.14 ±â€Š1.38, P < .001), HRtilt (SMD ±â€Š95% CI = 0.92 ±â€Š0.24, P < .001), HROR (0.50 ±â€Š0.27, P < .001), and the ratio of low frequency power to high frequency power of HRVrest (0.39 ±â€Š0.22, P < .001) were higher in ME/CFS patients compared to controls, while HRmax (MD ±â€Š95% CI = -13.81 ±â€Š4.15, P < .001), HR at anaerobic threshold (SMD ±â€Š95% CI = -0.44 ±â€Š0.30, P = 0.005) and the high frequency portion of HRVrest (-0.34 ±â€Š0.22, P = .002) were lower in ME/CFS patients. CONCLUSIONS: The differences in HR parameters identified by the meta-analysis indicate that ME/CFS patients have altered autonomic cardiac regulation when compared to healthy controls. These alterations in HR parameters may be symptomatic of the condition.


Assuntos
Sistema Nervoso Autônomo/fisiopatologia , Encefalomielite/fisiopatologia , Síndrome de Fadiga Crônica/fisiopatologia , Coração/fisiopatologia , Adulto , Idoso , Exercício/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome , Teste da Mesa Inclinada
4.
Herz ; 44(8): 759-768, 2019 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-31620824

RESUMO

The clarification of syncope is a diagnostic challenge as possible causes often occur only intermittently. Therefore, a detailed and standardized anamnesis is essential as it 1) differentiates syncope from other transient losses of consciousness (TLOC) and 2) directly clarifies possible causes of syncope. The risk stratification plays a central and very important role in order to avoid unnecessary examinations in patients with benign syncope and to provide patients with life-threatening, mostly cardiac syncopal episodes with timely diagnostics and treatment. In cases where the cause of syncope is still unclear, a standardized approach is indicated using extended diagnostics, such as a tilt table examination, a carotid sinus pressure test, prolonged telemetric monitoring or clarification with an implantable loop recorder (ILR).


Assuntos
Síncope , Diagnóstico Diferencial , Eletrocardiografia Ambulatorial , Humanos , Síncope/diagnóstico , Teste da Mesa Inclinada
5.
BMJ Case Rep ; 12(9)2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31537586

RESUMO

Postural orthostatic tachycardia syndrome (POTS) is a heterogeneous autonomic disorder characterised by orthostatic intolerance and a rise in heart rate by at least 30 bpm or an absolute heart rate value of at least 120 bpm within 10 min of standing or during a tilt table test. Overwhelmingly, POTS affects young Caucasian women, which can lead physicians to miss the diagnosis in men or non-white patients. We describe a case of 29-year-old African-American man who developed lightheadedness, generalised weakness, tachycardia and palpitations and was subsequently diagnosed with POTS. We review its clinical features, differential diagnosis, pathophysiology and treatment options. We also emphasise that POTS should be considered as a differential diagnosis in any patient presenting with typical clinical features, who may not be in the usual demographics of the disorder.


Assuntos
Tontura/etiologia , Síndrome da Taquicardia Postural Ortostática/diagnóstico , Síndrome da Taquicardia Postural Ortostática/terapia , Taquicardia/etiologia , Adulto , Afro-Americanos/etnologia , Diagnóstico Diferencial , Humanos , Masculino , Síndrome da Taquicardia Postural Ortostática/fisiopatologia , Atenção Primária à Saúde , Sódio/administração & dosagem , Teste da Mesa Inclinada/métodos , Resultado do Tratamento
6.
Turk J Pediatr ; 61(1): 52-58, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31559722

RESUMO

Lin J, Zhao H, Ma L, Jiao F. Body mass index is decreased in children and adolescents with postural tachycardia syndrome. Turk J Pediatr 2019; 61: 52-58. Our intent was to explore the predictive value of body mass index (BMI) in differentiating between vasovagal syncope (VVS) and postural tachycardia syndrome (POTS) in children and adolescents. A total of 111 children and adolescents with POTS and 154 children and adolescents with VVS were included in our study. The control group included 82 healthy children and adolescents. Height and weight were measured in all participants. The headup tilt test was performed in participants in all groups (POTS, VVS, and control). BMI was significantly lower in children and adolescents with POTS (18.3±3.4) than in children and adolescents with VVS (20.3±4.2) and the control group (20.5±2.9). The receiver operating characteristic curve was performed to determine the predictive value of BMI differentiation between POTS and VVS and showed that a BMI of 19.30 was the cutoff value for the probability of distinction. However, the results (BMI of 19.30) produced unsatisfactory sensitivity (57.1%) and specificity (28.8%) rates of correctly discriminating between patients with POTS and patients with VVS. Children and adolescents with POTS have a lower BMI compared with healthy peers or children and adolescents with VVS.


Assuntos
Índice de Massa Corporal , Síndrome da Taquicardia Postural Ortostática/diagnóstico , Síncope Vasovagal/diagnóstico , Adolescente , Estudos de Casos e Controles , Criança , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Síndrome da Taquicardia Postural Ortostática/patologia , Síndrome da Taquicardia Postural Ortostática/fisiopatologia , Curva ROC , Estudos Retrospectivos , Sensibilidade e Especificidade , Síncope Vasovagal/patologia , Síncope Vasovagal/fisiopatologia , Teste da Mesa Inclinada
7.
Turk J Pediatr ; 61(1): 85-91, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31559726

RESUMO

Bilici M, Fidanci-Dedeoglu Z, Demir F, Akin A, Türe M, Balik H, Tan I, Ertugrul S. Prolonged QT dispersion is associated with pediatric syncope. Turk J Pediatr 2019; 61: 85-91. We aimed to find out whether QT dispersion can be used as a diagnostic marker in terms of syncope type, and recurrence risk. Fifty-two patients (28 male, 53.8%) admitted to the pediatric cardiology clinic with syncope were compared with 50 healthy controls (28 male, 56%; mean age: 13.8±2.3 years, range: 11-17 years) for QT dispersion (QTd) and other electrocardiographic findings. Gender, age, echocardiography, blood pressure while standing and sitting, electrolyte levels, liver and kidney function tests, and QTd and QTcd (calculated with corrected QT: QTc) in electrocardiography (ECG) of patients were all evaluated. Patients` ages varied between 7-17 years and the mean age at first syncope was 13.9±2.4 years. Mean follow-up duration of the patients was 10±5 months (range: 5-18 months). Mean number of syncope attacks was 2.8±2.2. QTd (72±46 ms vs. 34±14 ms) and QTcd (77±45 ms vs. 33±14 ms) values of the patients were significantly longer, compared to control group (p < 0.001). The age, gender, QTd, and QTcd values did not differ between the subtypes of syncope based on pathogenetic mechanism. Additionally, these parameters did not differ in terms of the number of syncope recurrence and tilt test. Patients` complaints reduced after cardiologic evaluation and advice regarding prevention of syncope. We think that in follow-up period, education and preventive precautions that can be taken in the daily life must be emphasized, and drug treatment can be started in unresponsive cases.


Assuntos
Eletrocardiografia , Síncope/fisiopatologia , Adolescente , Estudos de Casos e Controles , Criança , Feminino , Humanos , Masculino , Teste da Mesa Inclinada
8.
BMJ Case Rep ; 12(8)2019 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-31434666

RESUMO

A 62-year-old man presented with a 2-year history of syncope, collapse and fluctuating blood pressure (BP). His medications included midodrine (10 mg, three times per day) and fludrocortisone (0.1 mg, two times per day), but neither treatment afforded symptomatic relief. Autonomic testing was performed. Head-up tilt table testing revealed a supine BP of 112/68 mm Hg (heart rate, 74 beats per minute (bpm)) after 6 min, which dropped to 76/60 mm Hg (83 bpm) within 2 min of 80° head-up tilt. Findings from a heart rate with deep breathing test and a Valsalva test were consistent with autonomic dysfunction. The patient was diagnosed with neurogenic orthostatic hypotension and treated with droxidopa (100 mg, two times per day; titrated to 100 mg, one time per day). After initiating treatment with droxidopa, the patient no longer reported losing consciousness on standing and experienced improvement in activities of daily living. These improvements were maintained through 1 year of follow-up.


Assuntos
Antiparkinsonianos/uso terapêutico , Sistema Nervoso Autônomo/fisiopatologia , Droxidopa/uso terapêutico , Hipotensão Ortostática/diagnóstico , Síncope/etiologia , Teste da Mesa Inclinada , Acidentes por Quedas , Atividades Cotidianas , Humanos , Hipotensão Ortostática/tratamento farmacológico , Hipotensão Ortostática/fisiopatologia , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
9.
Artigo em Russo | MEDLINE | ID: mdl-31407676

RESUMO

AIM: To define the mechanism of formation of orthostatic hypotension in patients with traumatic tetraplegia. MATERIAL AND METHODS: The study included 64 patients with chronic (more 6 month) and subacute (less 6 month) tetraplegia; the period of observation was about 30 days after admission to the rehabilitation center. Changes in the state of the autonomic nervous systems (heart rate variability at rest and head-up tilt test, sinus arrhythmia) were studied. RESULTS: In the first 6 months, all patients, and after 6-12 months, one third of the patients experienced orthostatic hypotension, which was accompanied by lower values of the normalized sympatovagal index (LFn/HFn) 0.35 (0.260; 0.650) and expiratory-inspiratory coefficient (RRmax/RRmin) 1.09 (1.040; 1200). An increase in expiratory-inspiratory coefficient as a result of physical rehabilitation up to 1.16 (1.120; 1.24) was noted only in patients less than 6 months after injury. CONCLUSION: Both sympathetic and parasympathetic parts of the autonomic nervous system are involved in the formation of orthostatic hypotension syndrome in patients with spinal tetraplegia.


Assuntos
Hipotensão Ortostática , Doenças da Medula Espinal , Sistema Nervoso Autônomo , Frequência Cardíaca , Humanos , Hipotensão Ortostática/etiologia , Doenças da Medula Espinal/complicações , Teste da Mesa Inclinada
11.
Handb Clin Neurol ; 160: 419-433, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31277866

RESUMO

The evaluation of autonomic function requires indirect assessment of neurophysiologic function using specialized equipment that is often available only at tertiary care centers, with few specialists available. However, the evaluation of autonomic function is rooted in basic physiology, and the results can be interpreted by careful consideration of the context of the problem. Many automated devices have become widely available to test autonomic function, but they tend to gather inadequate data leading to frequent misdiagnosis and clinical confusion. We review the details necessary for the neurophysiologist to properly perform, and interpret, autonomic function testing.


Assuntos
Doenças do Sistema Nervoso Autônomo/diagnóstico , Sistema Nervoso Autônomo/fisiologia , Reflexo/fisiologia , Sudorese/fisiologia , Manobra de Valsalva/fisiologia , Sistema Nervoso Autônomo/fisiopatologia , Doenças do Sistema Nervoso Autônomo/fisiopatologia , Humanos , Teste da Mesa Inclinada/métodos
12.
Beijing Da Xue Xue Bao Yi Xue Ban ; 51(3): 430-438, 2019 Jun 18.
Artigo em Chinês | MEDLINE | ID: mdl-31209413

RESUMO

OBJECTIVE: To quantify the relationship between cerebral blood flow velocity and peripheral blood pressure during hypotension period, aiming to predict the brain hypotension before symptomatic occurrence. METHODS: Twenty vasovagal syncope (VVS) patients who had a previous clinical history were selected in groups and 20 pair-matched control subjects underwent 70° tilt-up test. The subjects remained supine for 30 minutes before recordings when Doppler probes, electrodes and Finapres device were prepared. After continuous baseline recordings for 10 min, the subjects underwent head up tilt (HUT) test (70°), and were standing upright for 30 minutes or until syncope was imminent. For ethical reasons, the subjects were turned back to supine position immediately after SBP dropped to ≥20 mmHg, when their consciousness persisted. The point of syncope was synchronized for all the subjects by the point SBP reached the minima. Their beat-to-beat blood pressures (BP) were recorded continuously and bilateral middle cerebral artery (MCA) flow velocities were obtained with two 2 MHz Doppler probes from a transcranial Doppler ultrasonography (TCD) system. A nonlinear dynamic method--multimodal pressure flow (MMPF) analysis was introduced to access cerebral autoregulation during different time intervals. We introduced a new indicator--syncope index (SI), which was extracted from blood flow velocity (BFV) signal to evaluate the variation of cerebral vascular tension, and could reflect the deepness of dicrotic notch in BFV signal. RESULTS: Compared with the syncope index of the baseline value at the beginning of the tilt test, SI in VVS group showed significantly lower when the VVS occurred (0.16±0.10 vs.0.27±0.10,P<0.01),while there was no significant difference in syncope index between the control group at the end of the tilt test and the baseline value at the beginning of the tilt test. For those VVS patients, pulse index and resistance index had no significant change. Syncope index decreased significantly 3 minutes before the point of syncope (0.23±0.07 vs.0.29±0.07,P<0.01). CONCLUSION: Dynamic regulation is exhausted when vasovagal syncope occurred. Tension decrease of small vessels could have some relationship with loss of the cerebral autoregulation capability. The proposed syncope index could be a useful parameter in predicting syncope of VVS patients since it decreased significantly up to 3 minutes earlier from the point of syncope.


Assuntos
Síncope Vasovagal , Pressão Sanguínea , Frequência Cardíaca , Humanos , Dinâmica não Linear , Síncope , Teste da Mesa Inclinada
13.
Med. infant ; 26(2): 205-210, Junio 2019. ilus
Artigo em Espanhol | LILACS | ID: biblio-1021615

RESUMO

El síncope es una pérdida transitoria de conciencia y tono postural debido a hipoflujo sanguíneo cerebral que se recupera espontáneamente sin maniobras de RCP. En esta actualización se plantea el síncope vasovagal con sus diagnósticos diferenciales y posibles etiologías, fisiopatología y métodos de estudios. También se presenta la experiencia sobre este tema en nuestro hospital su estudio, tratamiento y diagnostico (tilt test) (AU)


Syncope is a transient loss of consciousness and postural tone due to cerebral blood hypoflow that recovers spontaneously without CPR maneuvers. This update discusses vasovagal syncope with its differential diagnoses and possible etiologies, pathophysiology, and diagnostic methods. Additionally, the experience on this topic of our hospital regarding investigations, treatment, and diagnosis is presented. (AU)


Assuntos
Humanos , Criança , Adolescente , Teste da Mesa Inclinada/instrumentação , Síncope Vasovagal/diagnóstico , Síncope Vasovagal/etiologia , Síncope Vasovagal/fisiopatologia , Síncope Vasovagal/terapia , Diagnóstico Diferencial
15.
Rev Invest Clin ; 71(2): 124-132, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31056593

RESUMO

Background: Vasovagal syncope (VVS) is a frequent clinical condition in which a genetic background seems to be implicated. Considering that the adrenergic receptors (ARs) may play a role in VVS, the present study has as principal aim to determine if the α- and ß-AR (ADRA and ADRB) gene polymorphisms are associated with an increased risk to have a positive head-up tilt table (HUTT) test in patients with VVS. Methods: Nine polymorphisms in the ADRA1A (rs1048101, rs1383914, rs574584, and rs573542), ADRB1 (rs1801252 and rs1801253), ADRB2 (rs1042713 and rs1042714), and ADRB3 (rs4994) genes were analyzed using the 5' exonuclease TaqMan genotyping assay in a group of 134 patients with VVS. Results: Under different models, the rs1801252 (OR = 8.63, 95% CI: 0.95-78.72, Precessive = 0.02), rs1042713 (OR = 1.94, 95% CI: 1.02-3.66, Padditive = 0.04), and rs4994 (OR = 2.46, 95% CI: 1.01-6.01, Pdominant = 0.042 and OR = 2.62, 95% CI: 1.04-6.63, Pover-dominant = 0.03) polymorphisms were associated with increased risk for a positive HUTT. All models were adjusted for statistically significant covariates. Conclusion: These results suggest that some polymorphisms of the ß-AR genes could contribute to a positive tilt test in patients with VVS.


Assuntos
Receptores Adrenérgicos beta/genética , Síncope Vasovagal/diagnóstico , Teste da Mesa Inclinada , Adulto , Feminino , Genótipo , Humanos , Masculino , Polimorfismo Genético , Síncope Vasovagal/genética , Adulto Jovem
16.
J Neurol ; 266(Suppl 1): 74-79, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31049730

RESUMO

INTRODUCTION: Mal de Debarquement Syndrome (MdDS) is the rare condition of enduring rocking sensations and subjective unsteadiness following a lengthy exposure to passive motion. The pathogenesis of MdDS is unknown and the available treatment is limited. Here, we developed an experimental model of MdDS that may facilitate systematic inquiry of MdDS pathophysiology and the development of prevention or treatment strategies for this condition. METHODS: In an initial series of pilot experiments, suitable stimulation devices and conditions were evaluated. The final paradigm consisted of a low-frequency oscillatory motion stimulation, simultaneously deployed as roll and pitch rotation as well as heave on a six-degrees-of-freedom motion platform. Twelve healthy participants were stimulated under this condition for 30 min during free stance. Aftereffects with respect to rocking sensations and posturographic sway were monitored up to 60 min post-stimulation and compared to an initial pre-stimulation assessment as well as to posturographic recordings of spontaneous sway in ten patients with MdDS. RESULTS: Motion stimulation consistently evoked MdDS-like rocking sensations and postural alterations that lasted up to 45 min after cessation of passive motion exposure. Body sway alterations were most pronounced in anterior-posterior dimension during standing with eyes closed and primarily characterized by a distinct peak in the low-frequency sway spectrum close to stimulation frequency. These postural aftereffects further closely resembled spontaneous oscillatory low-frequency sway observed in patients with MdDS. CONCLUSION: Subsequent neurophysiological and imaging examinations are required to investigate whether the model of transient, experimental MdDS actually shares a common substrate with the enduring pathological condition of MdDS.


Assuntos
Modelos Teóricos , Percepção de Movimento/fisiologia , Equilíbrio Postural/fisiologia , Teste da Mesa Inclinada/métodos , Doença Relacionada a Viagens , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto
17.
PLoS One ; 14(4): e0214733, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30998713

RESUMO

The study aims to clarify the mechanism in patients with neurally mediated syncope (NMS), focusing on the adenylate cyclase (AC) activity level in lymphocytes. This study included 40 subjects: 22 healthy volunteers and 18 NMS patients. We investigated the changes in AC activity that occur during of syncope at rest and during the head-up tilt (HUT) test. We obtained 8 mL of blood at rest time and four times during the HUT test. Then, we measured the AC activity and the test reagent was added to the lymphocytes (10,000) and reacted for 30 min at room temperature. We were able to determine the standard value of AC activity when adrenaline (AD) and isoproterenol (IP) were added to lymphocytes. The results of our study showed one of the causes of NMS has a difference in AC activity level and classification of the patients into two different types of NMS was possible: either the vasodepressor type (VT) or mixed type (MT). At rest time, VT patients showed significantly higher AC activity (AD; 100 µM: p = 0.005, IP; 50 µM: p = 0.02) and MT patients showed significantly lower AC activity (AD; 10 µM: p = 0.02, IP; 50 µM: p = 0.004) than the average AC activity in healthy volunteers. Moreover, VT patients had significantly higher AC activity than healthy volunteers at the four points of the HUT test. MT patients had significantly lower AC activity (AD: p = 0.04 and IP: p = 0.04) than healthy volunteers at the rest time of HUT. Our study showed a significant difference in AC activities between NMS patients and healthy volunteers at rest. Therefore, a detailed NMS diagnosis can be made by examining AC activity levels in blood taken at rest time.


Assuntos
Adenilil Ciclases/análise , Síncope Vasovagal/diagnóstico , Adenilil Ciclases/metabolismo , Adulto , Idoso , Pressão Sanguínea , Estudos de Casos e Controles , Ativação Enzimática/efeitos dos fármacos , Epinefrina/farmacologia , Feminino , Humanos , Isoproterenol/farmacologia , Japão , Linfócitos/citologia , Linfócitos/metabolismo , Pessoa de Meia-Idade , Estações do Ano , Teste da Mesa Inclinada , Adulto Jovem
18.
Indian Heart J ; 71(1): 1-6, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31000176

RESUMO

BACKGROUND: Carotid sinus syndrome accounts for one third of patients who presents with unexplained syncope. Prevalence of carotid sinus hypersensitivity (CSH) in Indians has not been studied till now. OBJECTIVES: To assess the prevalence and associations of CSH in symptomatic patients above 50 years and to study its prognostic significance pertaining to sudden cardiac death, syncope, recurrent pre syncope and falls on 1 year follow up. METHODS: Patients above 50 years who presented with unexplained syncope, recurrent syncope or falls were considered cases and those without these symptoms were considered as controls. All the patients underwent carotid sinus massage and their responses noted. All symptomatic patients were followed up and observed for events like sudden cardiac death, syncope, recurrent pre syncope and falls during 1 year follow up. Patients with recurrent syncope and predominant cardioinhibitory syncope were advised permanent pacemaker implantation. RESULTS: A total of 252 patients were screened, 130 patients constituted cases and 49 patients constituted controls. CSH was demonstrable in 32% (n = 42) of cases as compared to 8% (n = 4) in controls (p < 0.001). Cardioinhibitory response was the predominant response (88%, n = 38) followed by mixed response (12%, n = 4). CSH was associated with advancing age, male gender (93%, n = 39, p < 0.001) and history of smoking (63%, n = 27, p = 0.009). Composite outcomes of sudden cardiac death, syncope, recurrent pre syncope and falls were significantly higher in patients with symptomatic CSH than in those without it (45%, n = 16 vs. 6.8%, n = 6; p < 0.001). CONCLUSIONS: In conclusion, the prevalence of CSH in patients above 50 yrs with unexplained syncope was high in our population. Patients with CSH and baseline symptoms developed recurrent syncope during follow up. Carotid sinus massage should be a part of routine examination protocol for unexplained syncope.


Assuntos
Seio Carotídeo/fisiopatologia , Síndrome do Nó Sinusal/complicações , Síncope/etiologia , Idoso , Pressão Sanguínea , Eletrocardiografia Ambulatorial , Feminino , Seguimentos , Humanos , Índia/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Síndrome do Nó Sinusal/diagnóstico , Síndrome do Nó Sinusal/epidemiologia , Síncope/fisiopatologia , Síndrome , Teste da Mesa Inclinada , Fatores de Tempo
19.
Diabetes Res Clin Pract ; 151: 152-162, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31004672

RESUMO

STUDY HYPOTHESIS: Cardiac autonomic dysfunction might lead to higher vaso vagal syncope (VVS) recurrence rate in type 2 diabetes mellitus (T2DM) patients vs. non diabetics patients. BACKGROUND: VVS recurrence might be due to alterations of autonomic system function, as assessed by heart rate variability (HRV). To date, in this study we investigated the correlation between HRV alterations and VVS recurrence at 12 months of follow up in T2DM vs. non T2DM patients. MATERIALS AND METHODS: In a prospective multicenter study we studied a propensity score matching (PSM) analysis of 121 T2DM vs. 121 non T2DM patients affected by VVS. RESULTS: T2DM vs. non T2DM patients had at baseline a higher rate of HRV dysfunction, and this was linked to higher rate of VVS recurrence at 12 months of follow up (p < 0.05). Blood pressure alterations and lower LF/HF ratio were linked to higher rate of all cause syncope recurrence, and of vasodepressor, cardio inhibitory, and mixed syncope recurrence (p < 0.05). Anti hypertensive drug therapies increased the number of vasodepressor and mixed syncope events (p < 0.05); alterations of heart rate increased syncope recurrence and mixed syncope recurrence events (p < 0.05). Finally, T2DM was linked to higher rate of VVS recurrence, and specifically of vasodepressor and mixed VVS recurrence (p < 0.05). CONCLUSIONS: T2DM patients have alterations of the autonomic nervous system, as result of cardiac autonomic neuropathy. However, T2DM diagnosis and autonomic dysfunction assessed by HRV alterations predicted VVS recurrence.


Assuntos
Diabetes Mellitus Tipo 2/complicações , Cardiopatias/complicações , Síncope Vasovagal/etiologia , Teste da Mesa Inclinada/métodos , Diabetes Mellitus Tipo 2/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Síncope Vasovagal/patologia
20.
BMJ Case Rep ; 12(4)2019 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-31005863

RESUMO

Syncope is a sudden loss and gain of consciousness. Traditionally, it is caused by the abnormalities of neurological, cardiac or vasovagal systems. We present a case of a 19-year-old woman presenting with recurrent syncopal episodes with no apparent cause. Examination and investigations were unremarkable for any aetiology except positive tilt tests for postural orthostatic tachycardia syndrome. The purpose of this report is to make physicians aware of the unique presentation of this rare aetiology with recurrent syncopal episodes and the novel management approach.


Assuntos
Fármacos Cardiovasculares/uso terapêutico , Ivabradina/uso terapêutico , Síndrome da Taquicardia Postural Ortostática/tratamento farmacológico , Síncope/etiologia , Eletrocardiografia , Feminino , Humanos , Síndrome da Taquicardia Postural Ortostática/complicações , Síndrome da Taquicardia Postural Ortostática/diagnóstico , Teste da Mesa Inclinada , Adulto Jovem
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