RESUMO
Electroacupuncture at Neiguan point (PC6) effectively ameliorates tachycardia. However, very little is known about the neural pathway mechanism underlying the effect of electroacupuncture at PC6 in stress-induced tachycardia. Here, we investigate whether there exists a dorsomedial hypothalamus (DMH)-raphe pallidus (RP)-heart pathway to mediate the effect of electroacupuncture at PC6. The virus tracing results show that the heart is innervated by the neurons in DMH and RP, and the neurons of DMH project to RP. Chemogenetic inhibition of RP projecting DMH neurons reverses the cardiac autonomic imbalance and tachycardia induced by stress. Of note, immunofluorescence results show that the neural activity of DMH and RP is inhibited by electroacupuncture at PC6 accompanied with improved cardiac autonomic imbalance and tachycardia under stress. Moreover, chemogenetic inhibition of RP projecting DMH neurons cannot affect autonomic nervous activity and heart rate of stress rats after administrating electroacupuncture at PC6.NEW & NOTEWORTHY Our study suggests that this dorsomedial hypothalamus (DMH)-raphe pallidus (RP)-cardiac sympathetic pathway involves in the improvement of cardiac dysfunction associated with stress by administrating electroacupuncture at PC6, thus providing beneficial information for the development of therapeutic strategies to prevent stress-induced cardiovascular diseases, and insight into neural pathway basis for electroacupuncture at PC6 intervention of cardiac dysfunction.
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Eletroacupuntura , Ratos , Animais , Taquicardia , Coração , Frequência Cardíaca/fisiologia , HipotálamoRESUMO
AIMS: Although the mechanism of an atrial tachycardia (AT) can usually be elucidated using modern high-resolution mapping systems, it would be helpful if the AT mechanism and circuit could be predicted before initiating mapping. OBJECTIVE: We examined if the information gathered from the cycle length (CL) of the tachycardia can help predict the AT-mechanism and its localization. METHODS: One hundred and thirty-eight activation maps of ATs including eight focal-ATs, 94 macroreentrant-ATs, and 36 localized-ATs in 95 patients were retrospectively reviewed. Maximal CL (MCL) and minimal CL (mCL) over a minute period were measured via a decapolar catheter in the coronary sinus. CL-variation and beat-by-beat CL-alternation were examined. Additionally, the CL-respiration correlation was analysed by the RhythmiaTM system. : Both MCL and mCL were significantly shorter in macroreentrant-ATs [MCL = 288 (253-348) ms, P = 0.0001; mCL = 283 (243-341) ms, P = 0.0012], and also shorter in localized-ATs [MCL = 314 (261-349) ms, P = 0.0016; mCL = 295 (248-340) ms, P = 0.0047] compared to focal-ATs [MCL = 506 (421-555) ms, mCL = 427 (347-508) ms]. An absolute CL-variation (MCL-mCL) < 24â ms significantly differentiated re-entrant ATs from focal-ATs with a sensitivity = 96.9%, specificity = 100%, positive predictive value (PPV) = 100%, and negative predictive value (NPV) = 66.7%. The beat-by-beat CL-alternation was observed in 10/138 (7.2%), all of which showed the re-entrant mechanism, meaning that beat-by-beat CL-alternation was the strong sign of re-entrant mechanism (PPV = 100%). Although the CL-respiration correlation was observed in 28/138 (20.3%) of ATs, this was predominantly in right-atrium (RA)-ATs (24/41, 85.7%), rather than left atrium (LA)-ATs (4/97, 4.1%). A positive CL-respiration correlation highly predicted RA-ATs (PPV = 85.7%), and negative CL-respiration correlation probably suggested LA-ATs (NPV = 84.5%). CONCLUSION: Detailed analysis of the tachycardia CL helps predict the AT-mechanism and the active AT chamber before an initial mapping.
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Ablação por Cateter , Taquicardia Supraventricular , Humanos , Estudos Retrospectivos , Técnicas Eletrofisiológicas Cardíacas , Taquicardia , Átrios do Coração , Resultado do TratamentoRESUMO
Mutations in thyroid hormone receptor α1 (TRα1) cause Resistance to Thyroid Hormone α (RTHα), a disorder characterized by hypothyroidism in TRα1-expressing tissues including the heart. Surprisingly, we report that treatment of RTHα patients with thyroxine to overcome tissue hormone resistance does not elevate their heart rate. Cardiac telemetry in male, TRα1 mutant, mice indicates that such persistent bradycardia is caused by an intrinsic cardiac defect and not due to altered autonomic control. Transcriptomic analyses show preserved, thyroid hormone (T3)-dependent upregulation of pacemaker channels (Hcn2, Hcn4), but irreversibly reduced expression of several ion channel genes controlling heart rate. Exposure of TRα1 mutant male mice to higher maternal T3 concentrations in utero, restores altered expression and DNA methylation of ion channels, including Ryr2. Our findings indicate that target genes other than Hcn2 and Hcn4 mediate T3-induced tachycardia and suggest that treatment of RTHα patients with thyroxine in high dosage without concomitant tachycardia, is possible.
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Síndrome da Resistência aos Hormônios Tireóideos , Tiroxina , Masculino , Animais , Camundongos , Tiroxina/uso terapêutico , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/genética , Síndrome da Resistência aos Hormônios Tireóideos/genética , Hormônios Tireóideos , Receptores alfa dos Hormônios Tireóideos/genética , Receptores alfa dos Hormônios Tireóideos/metabolismo , Mutação , Taquicardia/genéticaRESUMO
BACKGROUND: The benefit of an anterior mitral line (AML) in patients with persistent atrial fibrillation (AF) and anterior atrial scar undergoing ablation has never been investigated. OBJECTIVE: The purpose of this study was to evaluate the outcomes of AML in addition to standard treatment compared to standard treatment alone (no AML) in this subset of patients. METHODS: Patients with persistent AF and anterior low-voltage zone (LVZ) treated with AML in 3 centers were retrospectively enrolled. The patients were matched in 1:1 fashion with patients having persistent AF and anterior LVZ who underwent conventional ablation in the same centers. Matching parameters were age, LVZ burden, and repeated ablation. Primary endpoint was AF/atrial tachycardia (AT) recurrence. RESULTS: One hundred eight-six patients (age 66 ± 9 years; 34% women) were selected and divided into 2 matched groups. Bidirectional conduction block was achieved in 95% of AML. After median follow-up of 2 years, AF/AT recurrence occurred in 29% of the patients in the AML group vs 48% in the no AML group (log-rank P = .024). On Cox regression multivariate analysis, left atrial volume (hazard ratio [HR] 1.03; P = .006) and AML (HR 0.46; P = .003) were significantly associated with the primary endpoint. On univariate logistic regression, lower body mass index, older age, extensive anterior LVZ, and position of the left atrial activation breakthrough away from the AML were associated with first-pass AML block. CONCLUSION: In this retrospective matched analysis of patients with persistent AF and anterior scar, AML in addition to standard treatment was associated with improved AF/AT-free survival compared to standard treatment alone.
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Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Masculino , Fibrilação Atrial/complicações , Fibrilação Atrial/cirurgia , Estudos Retrospectivos , Cicatriz/diagnóstico , Cicatriz/etiologia , Resultado do Tratamento , Técnicas Eletrofisiológicas Cardíacas , Taquicardia , Recidiva , Veias Pulmonares/cirurgiaRESUMO
The ectopic co-expression of taste and olfactory receptors in cardiomyocytes provides not only possibilities for the construction of biomimetic gustatory and olfactory sensors but also promising novel therapeutic targets for tachycardia treatment. Here, bitter taste and olfactory receptors endogenously expressed in HL-1 cells were verified by RT-PCR and immunofluorescence staining. Then HL-1 cardiomyocyte-based integrated gustatory and olfactory sensing array coupling with the microelectrode array (MEA) was first constructed for drugs screening and evaluation for tachycardia treatment. The MEA sensor detected the extracellular field potentials and reflected the systolic-diastolic properties of cardiomyocytes in real time in a label-free and non-invasive way. The in vitro tachycardia model was constructed using isoproterenol as the stimulator. The proposed sensing array facilitated potential drug screening for tachycardia treatment, such as salicin, artemisinin, xanthotoxin, and azelaic acid which all activated specific receptors on HL-1 cells. IC50 values for four potential drugs were calculated to be 0.0036 µM, 309.8 µM, 14.68 µM, and 0.102 µM, respectively. Visualization analysis with heatmaps and PCA cluster showed that different taste and odorous drugs could be easily distinguished. The mean inter-class Euclidean distance between different bitter drugs was 1.681, which was smaller than the distance between bitter and odorous drugs of 2.764. And the inter-class distance was significantly higher than the mean intra-class Euclidean distance of 1.172. In summary, this study not only indicates a new path for constructing novel integrated gustatory and olfactory sensors but also provides a powerful tool for the quantitative evaluation of potential drugs for tachycardia treatment.
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Técnicas Biossensoriais , Receptores Odorantes , Humanos , Miócitos Cardíacos , Avaliação Pré-Clínica de Medicamentos , Biomimética , Olfato , Paladar , TaquicardiaRESUMO
Chronic fatigue syndrome (CFS), fibromyalgia, silicone breast implants syndrome (SBIs), COVID and post-COVID syndrome (PCS), sick building syndrome (SBS), post-orthostatic tachycardia syndrome (POTS), autoimmune diseases and autoimmune/inflammatory syndrome induced by adjuvants (ASIA) are frequently accompanied by clinical symptoms characteristic for dysautonomia: severe fatigue, dizziness, fogginess, memory loss, dry mouth and eyes, hearing dysfunction, tachycardia etc. The recent discovery of an imbalance of autoantibodies against G protein-coupled receptors (GPCR) in some autoimmune diseases, post-COVID syndrome, SBIs allowed researchers to assume the novel mechanism in these conditions - autoimmune autonomic nervous system imbalance. In this review, all data published on an imbalance of autoantibodies against GPCR, clinical symptoms and pathogenic mechanisms in CFS, Fibromyalgia, SBIs, COVID and PCS, SBS, POTS, and some autoimmune diseases were analyzed. Possible criteria to diagnose the autoimmune autonomic nervous system imbalance were created.
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Doenças Autoimunes , Implantes de Mama , COVID-19 , Síndrome de Fadiga Crônica , Fibromialgia , Disautonomias Primárias , Síndrome do Edifício Doente , Humanos , Síndrome de Fadiga Crônica/etiologia , Fibromialgia/etiologia , Implantes de Mama/efeitos adversos , COVID-19/complicações , Sistema Nervoso Autônomo , Autoanticorpos , Taquicardia , Adjuvantes Imunológicos , SiliconesRESUMO
We report a case of wide QRS tachycardia or ventricular tachycardia with a pulse after the administration of epinephrine under general anesthesia. After induction and achieving a sufficiently deep plane of general anesthesia, gauze soaked in a 1:100,000 epinephrine solution was applied to the patient's nasal mucosa and 1% lidocaine with 1:100,000 epinephrine was administered via intraoral infiltration. Several minutes after the start of surgery, the patient's blood pressure and heart rate suddenly increased and a wide QRS tachycardia was observed on the electrocardiogram, which then reverted to a normal sinus rhythm. According to the past reports, similar arrhythmias have occurred after administration of epinephrine in the head and neck. These findings suggest that anesthesia providers must be aware of the risks associated with epinephrine and local anesthetic use, particularly in the head and neck region.
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Epinefrina , Lidocaína , Anestesia Geral/efeitos adversos , Anestesia Local , Anestésicos Locais/efeitos adversos , Arritmias Cardíacas , Epinefrina/efeitos adversos , Humanos , Lidocaína/efeitos adversos , Taquicardia/induzido quimicamenteRESUMO
INTRODUCTION: Mitral valve surgery employing a superior transseptal approach (STA) is associated with arrhythmogenicity and intra-atrial conduction delay, despite being optimal for visualization of the surgical field. It is sometimes difficult to treat atrial tachycardias (AT) that arise after STA. To investigate AT circuits that arise after STA in detail in order to identify the optimal ablation line, using ultra-high-resolution mapping (UHRM). METHODS: We retrospectively analyzed 12 AT from 10 patients (median age 70 years, nine males) who had undergone STA surgery. The tachycardias were mapped using the Rhythmia mapping system (Boston Scientific, Natick, Massachusetts). RESULTS: The 12 STA-related AT (STA-AT) circuits were classifiable as follows according to location of the optimal ablation line: (1) peri-septal incision STA-AT (n = 3), (2) cavotricuspid isthmus (CTI) dependent STA-AT (n = 7), and (3) biatrial tachycardia (n = 2). Radiofrequency (RF) application terminated 11 of the 12 STA-AT. We found that difference in STA-AT circuit type was due to characteristics of the septal incision line made for STA. UHRM was important in identifying optimal ablation sites that did not create additional conduction disturbances in the right atrium (RA). CONCLUSIONS: ATs after STA involve complex arrhythmia circuits due to multiple and long incision lines in the RA. Accurate understanding of the arrhythmia circuit and sinus conduction in the RA after STA is recommended for treating post-surgical tachycardia in a minimally invasive manner.
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Bloqueio Atrioventricular , Ablação por Cateter , Taquicardia Supraventricular , Idoso , Arritmias Cardíacas/cirurgia , Bloqueio Atrioventricular/cirurgia , Técnicas Eletrofisiológicas Cardíacas , Humanos , Masculino , Valva Mitral/cirurgia , Estudos Retrospectivos , Taquicardia , Taquicardia Supraventricular/etiologia , Taquicardia Supraventricular/prevenção & controle , Taquicardia Supraventricular/cirurgia , Resultado do TratamentoRESUMO
The study aimed to investigate if vegetable-based high-energy mash diets supplemented with NaHCO3, L-arginine + vitamin C, and vegetable oils were effective against tachycardia and polycythemia in the broiler chicken. A total of 256 Ross-308 day-old male broiler chicks were randomly distributed into eight dietary treatment groups in a three-way ANOVA with 2 × 2 × 2 factorial arrangement (three factors, i.e., NaHCO3, L-arginine + vitamin C, and vegetable oil each with two levels, e.g., 0 and 0.1% of NaHCO3 and L-arginine + vitamin C; 3 and 4% of vegetable oil supplemented with basal diet) for a period of 35 days. Iso-caloric and iso-nitrogenous diets were formulated and supplied ad libitum. The final live weight (FLW), average daily feed intake (ADFI), average daily gain (ADG), feed efficiency (FE), carcass traits, cardio-pulmonary morphometry, total protein (TP), hemoglobin (Hb), triiodothyronine (T3), incidence of tachycardia, and polycythemia were examined. Supplementation of NaHCO3 increased 2.2% ADFI, 5.5% FE, and 23.2% TP. The L-arginine + vitamin C increased 2.4% FLW and decreased 1.9% heart rate. Vegetable oil increased 1.3% ADFI, 4.2% ADG, 8.6% FE, 23.1% Hb, and 15.5% PCV. The NaHCO3, L-arginine + vitamin C, and vegetable oil additively interacted to increase 31.5% T3 at the expense of 21.1% of the weight of the right ventricle (RV). The RV:TV, carcass traits, and hemato-biochemical indices remained within normal range irrespective of the levels of the supplementations of the test ingredients. It was concluded that vegetable-based high-energy mash diets were not susceptible to tachycardia and polycythemia. The addition of NaHCO3 and L-arginine + vitamin C ameliorated the propensity of tachycardia and polycythemia without deteriorating performance, carcass traits, and hemato-biochemical indices of the broiler chicken in a dose-dependent manner.
Assuntos
Galinhas , Policitemia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Arginina/farmacologia , Ácido Ascórbico/metabolismo , Galinhas/fisiologia , Dieta/veterinária , Suplementos Nutricionais , Policitemia/veterinária , Taquicardia/veterinária , VerdurasRESUMO
BACKGROUND: Catheter ablation of right atrial (RA) tachycardia in patients who have extensive spontaneous RA scarring is challenging due to the complex substrate and the potential for multiple inducible atrial tachycardias (ATs). METHODS: Eighteen patients with scar-related RA AT and no prior cardiac surgery were enrolled. A total of 52 different ATs (mean 3.2 ± 1.5 ATs per patient) were observed. We endeavored to complete activation maps for 45 ATs. RESULTS: By analyzing activation maps, we classified ATs into six categories. The discrepant location and extension of ESAs were associated with different AT mechanisms. CONCLUSIONS: Multiple scar-related RA ATs were observed in patients without previous cardiac surgery. The detailed activation patterns of these ATs could be clearly demonstrated by using an ultra-high-density mapping system.
Assuntos
Procedimentos Cirúrgicos Cardíacos , Ablação por Cateter , Taquicardia Supraventricular , Cicatriz/diagnóstico por imagem , Técnicas Eletrofisiológicas Cardíacas , Humanos , Taquicardia/cirurgia , Taquicardia Supraventricular/diagnóstico , Taquicardia Supraventricular/cirurgia , Resultado do TratamentoRESUMO
BACKGROUND: Macro-reentrant atrial tachycardias (MATs) are a common complication after cardiac valve surgery. The MAT types and the effectiveness of MAT ablation might differ after different valve surgery. Data comparing the electrophysiological characteristics and the ablation results of MAT post-tricuspid or mitral valve surgery are limited. METHODS: Forty-eight patients (29 males, age 56.1 ± 13.3 years) with MAT after valve surgery were assigned to tricuspid valve (TV) group (n = 18) and mitral valve (MV) group (n = 30). MATs were mapped and ablated guided by a three-dimensional navigation system. The one-year clinical effectiveness was compared in two groups. RESULTS: Nineteen MATs were documented in TV group, including 16 cavo-tricuspid isthmus (CTI)-dependent AFL and 3 other MATs at right atrial (RA) free wall, RA septum and left atrial (LA) roof. Thirty-nine MATs were identified in MV group, including15 CTI-dependent AFL, 8 RA free wall scar-related, 2 RA septum scar-related, 8 peri-mitral flutter, 3 LA roof-dependent, 2 LA anterior scar-related, and 1 right pulmonary vein-related MAT. Compared with TV group, MV group had significantly lower prevalence of CTI-dependent AFL (38.5% vs. 84.2%), higher prevalence of left atrial MAT (35.9 vs.5.3%) and higher proportion of patients with left atrial MAT (40 vs. 5.6%), P = 0.02, 0.01 and 0.01, respectively. The acute success rate of MAT ablation (100 vs. 93.3%) and the one-year freedom from atrial tachy-arrhythmias (72.2 vs. 76.5%) was comparable in TV and MV group. No predictor for recurrence was identified. CONCLUSION: Although the types of MATs differed significantly in patients with prior TV or MV surgery, the acute and mid-term effectiveness of MAT ablation was comparable in two groups. TRIAL REGISTRATION: This study was registered as a part of EARLY-MYO-AF clinical trial at the website ClinicalTrials. gov (NCT04512222).
Assuntos
Ablação por Cateter , Eletrocardiografia , Átrios do Coração/fisiopatologia , Valva Mitral/cirurgia , Complicações Pós-Operatórias/fisiopatologia , Taquicardia/fisiopatologia , Valva Tricúspide/cirurgia , Diagnóstico Diferencial , Técnicas Eletrofisiológicas Cardíacas , Feminino , Átrios do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taquicardia/etiologia , Taquicardia/cirurgiaRESUMO
INTRODUCTION: Pulmonary vein isolation (PVI) is the cornerstone of atrial fibrillation (AF) catheter ablation. However, a PVI alone has been considered insufficient for persistent AF. This study aimed to evaluate the efficacy of persistent AF ablation targeting complex fractionated atrial electrogram (CFAE) areas within low voltage zones identified by high-resolution mapping in addition to the PVI. METHODS: We randomized 50 patients (mean age 58.4â±â9.5âyears old, 86.0% males) with persistent AF to a PVI + CFAE group and PVI only group in a 1:1 ratio. CFAE and voltage mapping was performed simultaneously using a Pentaray Catheter with the CARTO3 CONFIDENSE module (Biosense Webster, CA, USA). The PVI + CFAE group, in addition to the PVI, underwent ablation targeting low voltage areas (<0.5âmV during AF) containing CFAEs. RESULTS: The mean persistent AF duration was 24.0â±â23.1âmonths and mean left atrial dimension 4.9â±â0.5âcm. In the PVI + CFAE group, AF converted to atrial tachycardia (AT) or sinus rhythm in 15 patients (60%) during the procedure. The PVI + CFAE group had a higher 1-year AF free survival (84.0% PVI + CFAE vs 44.0 PVI only, Pâ=â.006) without antiarrhythmic drugs. However, there was no difference in the AF/AT free survival (60.0% PVI + CFAE vs 40.0% PVI only, Pâ=â.329). CONCLUSION: Persistent AF ablation targeting CFAE areas within low voltage zones using high-density voltage mapping had a higher AF free survival than a PVI only. Although recurrence with AT was frequent in the PVI+CFAE group, the sinus rhythm maintenance rate after redo procedures was 76%.
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Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Técnicas Eletrofisiológicas Cardíacas , Idoso , Antiarrítmicos/uso terapêutico , Fibrilação Atrial/tratamento farmacológico , Intervalo Livre de Doença , Técnicas Eletrofisiológicas Cardíacas/métodos , Feminino , Átrios do Coração , Humanos , Masculino , Pessoa de Meia-Idade , Veias Pulmonares/cirurgia , Recidiva , Cirurgia Assistida por Computador , Taquicardia/etiologiaRESUMO
Importance: The notion that caffeine increases the risk of cardiac arrhythmias is common. However, evidence that the consumption of caffeinated products increases the risk of arrhythmias remains poorly substantiated. Objective: To assess the association between consumption of common caffeinated products and the risk of arrhythmias. Design, Setting, and Participants: This prospective cohort study analyzed longitudinal data from the UK Biobank between January 1, 2006, and December 31, 2018. After exclusion criteria were applied, 386â¯258 individuals were available for analyses. Exposures: Daily coffee intake and genetic polymorphisms that affect caffeine metabolism. Main Outcomes and Measures: Any cardiac arrhythmia, including atrial fibrillation or flutter, supraventricular tachycardia, ventricular tachycardia, premature atrial complexes, and premature ventricular complexes. Results: A total of 386â¯258 individuals (mean [SD] age, 56 [8] years; 52.3% female) were assessed. During a mean (SD) follow-up of 4.5 (3.1) years, 16â¯979 participants developed an incident arrhythmia. After adjustment for demographic characteristics, comorbid conditions, and lifestyle habits, each additional cup of habitual coffee consumed was associated with a 3% lower risk of incident arrhythmia (hazard ratio [HR], 0.97; 95% CI, 0.96-0.98; P < .001). In analyses of each arrhythmia alone, statistically significant associations exhibiting a similar magnitude were observed for atrial fibrillation and/or flutter (HR, 0.97; 95% CI, 0.96-0.98; P < .001) and supraventricular tachycardia (HR, 0.96; 95% CI, 0.94-0.99; P = .002). Two distinct interaction analyses, one using a caffeine metabolism-related polygenic score of 7 genetic polymorphisms and another restricted to CYP1A2 rs762551 alone, did not reveal any evidence of effect modification. A mendelian randomization study that used these same genetic variants revealed no significant association between underlying propensities to differing caffeine metabolism and the risk of incident arrhythmia. Conclusions and Relevance: In this prospective cohort study, greater amounts of habitual coffee consumption were associated with a lower risk of arrhythmia, with no evidence that genetically mediated caffeine metabolism affected that association. Mendelian randomization failed to provide evidence that caffeine consumption was associated with arrhythmias.
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Cafeína/metabolismo , Café/efeitos adversos , Citocromo P-450 CYP1A2/genética , Estilo de Vida , Análise da Randomização Mendeliana/métodos , Polimorfismo Genético , Taquicardia/epidemiologia , Adulto , Idoso , Citocromo P-450 CYP1A2/metabolismo , Feminino , Seguimentos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Taquicardia/etiologia , Taquicardia/genética , Fatores de Tempo , Estados Unidos/epidemiologiaRESUMO
BACKGROUND AND PURPOSE: Damage to the insula results in cardiovascular complications. In rats, activation of N-methyl-d-aspartate receptors (NMDARs) in the intermediate region of the posterior insular cortex (iIC) results in sympathoexcitation, tachycardia and arterial pressure increases. Similarly, focal experimental hemorrhage at the iIC results in a marked sympathetic-mediated increase in baseline heart rate. The dorsomedial hypothalamic region (DMH) is critical for the integration of sympathetic-mediated tachycardic responses. Here, whether responses evoked from the iIC are dependent on a synaptic relay in the DMH was evaluated. METHODS: Wistar rats were prepared for injections into the iIC and DMH. Anatomical (tracing combined with immunofluorescence) and functional experiments (cardiovascular and sympathetic recordings) were performed. RESULTS: The iIC sends dense projections to the DMH. Approximately 50% of iIC neurons projecting to the DMH express NMDARs, NR1 subunit. Blockade of glutamatergic receptors in the DMH abolishes the cardiovascular and autonomic responses evoked by the activation of NMDARs in the iIC (change in mean arterial pressure 7 ± 1 vs. 1 ± 1 mmHg after DMH blockade; change in heart rate 28 ± 3 vs. 0 ± 3 bpm after DMH blockade; change in renal sympathetic nerve activity 23% ± 1% vs. -1% ± 4% after DMH blockade). Experimental hemorrhage at the iIC resulted in a marked tachycardia (change 89 ± 14 bpm) that was attenuated by 65% ± 5% (p = 0.0009) after glutamatergic blockade at the DMH. CONCLUSIONS: The iIC-induced tachycardia is largely dependent upon a glutamatergic relay in the DMH. Our study reveals the presence of an excitatory glutamatergic pathway from the iIC to the DMH that may be involved in the cardiovascular alterations observed after insular stroke.
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Núcleo Hipotalâmico Dorsomedial , Acidente Vascular Cerebral , Animais , Pressão Sanguínea , Frequência Cardíaca , Humanos , Hipotálamo , Ratos , Ratos Wistar , Transmissão Sináptica , Taquicardia/etiologiaRESUMO
BACKGROUND: Activation maps of scar-related atrial tachycardias (AT) can be challenging to interpret due to difficulty in inaccurate annotation of electrograms, and an arbitrarily predefined mapping window. A novel mapping software integrating vector data and applying an algorithmic solution taking into consideration global activation pattern has been recently described (Coherent™, Biosense Webster "Investigational"). OBJECTIVE: We aimed to assess the investigational algorithm to determine the mechanism of AT compared with the standard algorithm. METHODS: This study included patients who underwent ablation of scar-related AT using the Carto 3 and the standard activation algorithm. The mapping data were analyzed retrospectively using the investigational algorithm, and the mechanisms were evaluated by two independent electrophysiologists. RESULTS: A total of 77 scar-related AT activation maps were analyzed (89.6% left atrium, median tachycardia cycle length of 273 ms). Of those, 67 cases with a confirmed mechanism of arrhythmia were used to compare the activation software. The actual mechanism of the arrhythmia was more likely to be identified with the investigational algorithm (67.2% vs. 44.8%, p = .009). In five patients with dual-loop circuits, 3/5 (60%) were correctly identified by the investigational algorithm compared to 0/5 (0%) with the standard software. The reduced atrial voltage was prone to lead to less capable identification of mechanism (p for trend: .05). The investigational algorithm showed higher inter-reviewer agreement (Cohen's kappa .62 vs. .47). CONCLUSIONS: In patients with scar-related ATs, activation mapping algorithms integrating vector data and "best-fit" propagation solution may help in identifying the mechanism and the successful site of termination.
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Ablação por Cateter , Cicatriz , Algoritmos , Cicatriz/diagnóstico , Técnicas Eletrofisiológicas Cardíacas , Humanos , Estudos Prospectivos , Estudos Retrospectivos , TaquicardiaRESUMO
Because of its involvement in a wide variety of cardiovascular, metabolic and behavioural functions, the hypothalamus constitutes a potential target for neuromodulation in a number of treatment-refractory conditions. The precise neural substrates and circuitry subserving these responses, however, are poorly characterized to date. We sought to retrospectively explore the acute sequelae of hypothalamic region deep brain stimulation and characterize their neuroanatomical correlates. To this end we studied-at multiple international centres-58 patients (mean age: 68.5 ± 7.9 years, 26 females) suffering from mild Alzheimer's disease who underwent stimulation of the fornix region between 2007 and 2019. We catalogued the diverse spectrum of acutely induced clinical responses during electrical stimulation and interrogated their neural substrates using volume of tissue activated modelling, voxel-wise mapping, and supervised machine learning techniques. In total 627 acute clinical responses to stimulation-including tachycardia, hypertension, flushing, sweating, warmth, coldness, nausea, phosphenes, and fear-were recorded and catalogued across patients using standard descriptive methods. The most common manifestations during hypothalamic region stimulation were tachycardia (30.9%) and warmth (24.6%) followed by flushing (9.1%) and hypertension (6.9%). Voxel-wise mapping identified distinct, locally separable clusters for all sequelae that could be mapped to specific hypothalamic and extrahypothalamic grey and white matter structures. K-nearest neighbour classification further validated the clinico-anatomical correlates emphasizing the functional importance of identified neural substrates with area under the receiving operating characteristic curves between 0.67 and 0.91. Overall, we were able to localize acute effects of hypothalamic region stimulation to distinct tracts and nuclei within the hypothalamus and the wider diencephalon providing clinico-anatomical insights that may help to guide future neuromodulation work.
Assuntos
Afeto/fisiologia , Sistema Nervoso Autônomo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Cognição/fisiologia , Estimulação Encefálica Profunda/métodos , Hipotálamo/diagnóstico por imagem , Idoso , Sistema Nervoso Autônomo/fisiologia , Temperatura Corporal/fisiologia , Eletrodos Implantados , Feminino , Humanos , Hipotálamo/fisiologia , Hipotálamo/cirurgia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Taquicardia/diagnóstico por imagem , Taquicardia/fisiopatologiaRESUMO
Objective: The incidence of severe infectious complications after burn injury increases mortality by 40%. However, traditional approaches for managing burn infections are not always effective. High-voltage, pulsed electric field (PEF) treatment shortly after a burn injury has demonstrated an antimicrobial effect in vivo; however, the working parameters and long-term effects of PEF treatment have not yet been investigated. Approach: Nine sets of PEF parameters were investigated to optimize the applied voltage, pulse duration, and frequency or pulse repetition for disinfection of Pseudomonas aeruginosa infection in a stable mouse burn wound model. The bacterial load after PEF administration was monitored for 3 days through bioluminescence imaging. Histological assessments and inflammation response analyses were performed at 1 and 24 h after the therapy. Results: Among all tested PEF parameters, the best disinfection efficacy of P. aeruginosa infection was achieved with a combination of 500 V, 100 µs, and 200 pulses delivered at 3 Hz through two plate electrodes positioned 1 mm apart for up to 3 days after the injury. Histological examinations revealed fewer inflammatory signs in PEF-treated wounds compared with untreated infected burns. Moreover, the expression levels of multiple inflammatory-related cytokines (interleukin [IL]-1α/ß, IL-6, IL-10, leukemia inhibitory factor [LIF], and tumor necrosis factor-alpha [TNF-α]), chemokines (macrophage inflammatory protein [MIP]-1α/ß and monocyte chemoattractant protein-1 [MCP-1]), and inflammation-related factors (vascular endothelial growth factor [VEGF], macrophage colony-stimulating factor [M-CSF], and granulocyte-macrophage colony-stimulating factor [G-CSF]) were significantly decreased in the infected burn wound after PEF treatment. Innovation: We showed that PEF treatment on infected wounds reduces the P. aeruginosa load and modulates inflammatory responses. Conclusion: The data presented in this study suggest that PEF treatment is a potent candidate for antimicrobial therapy for P. aeruginosa burn infections.
Assuntos
Queimaduras/terapia , Desinfecção/métodos , Terapia por Estimulação Elétrica/métodos , Infecções por Pseudomonas/terapia , Infecção dos Ferimentos/terapia , Animais , Queimaduras/complicações , Queimaduras/microbiologia , Modelos Animais de Doenças , Eletroforese em Gel de Campo Pulsado , Inflamação , Pseudomonas aeruginosa , Sepse/etiologia , Sepse/imunologia , Taquicardia , Fator A de Crescimento do Endotélio Vascular , Infecção dos Ferimentos/microbiologiaRESUMO
BACKGROUND: High-density automated mapping of complex atrial tachycardias (ATs) requires accurate assessment of activation maps. A new local activation display module (HD coloring, Biosense Webster®) provides higher map resolution, a better delineation of potential block reducing color interpolation, and a new propagation display. We evaluated the accuracy of a dedicated local activation display compared with standard algorithm. METHODS: High-density maps from 10 AT were collected with a multipolar catheter and were displayed with standard activation or HD coloring. Six expert operators retrospectively analyzed activation maps and were asked to define (1) the tachycardia mechanism, (2) ablation target, and (3) level of difficulty to interpret those maps. RESULTS: Using HD coloring, operators were able to reach a correct diagnosis in 93% vs. 63%, p < 0.05 compared to standard activation maps. Time to diagnosis was shorter 1.9 ± 1.0 min vs. 3.9 ± 2.1 min, p < 0.05. Confidence level would have allowed ablation without necessity for entrainment maneuvers in 87% vs. 53%, p < 0.05. Operators would have needed to remap or proceed with multiple entrainments in 3% vs. 13% of cases, p < 0.05. Finally, ablation strategy was more accurately identified in 97% vs. 67%, p < 0.05. CONCLUSION: Activation mapping with the new HD coloring module allowed a more accurate, reliable, and faster interpretation of complex ATs mechanisms compared to standard activation maps.