Sympathetic arterial baroreflex hysteresis in humans: different patterns during low- and high-pressure levels.

Fluctuations in diastolic pressure modulate muscle sympathetic nerve activity (MSNA) through the arterial baroreflex. A higher sympathetic baroreflex sensitivity (sBRS) to pressure falls compared with rises has been reported; however, the underlying mechanisms are unclear. We assessed whether beat-to-beat falling and rising diastolic pressures operate on two distinct baroreflex response curves. Twenty-two men (32 ± 8 yr) underwent sequential bolus injections of nitroprusside and phenylephrine (modified Oxford test) with continuous recording of heart rate, blood pressure, and MSNA. The weighted negative linear regression slope between falling or rising diastolic pressure and MSNA burst incidence quantified sBRSfall and sBRSrise, respectively. The diastolic pressure evoking a MSNA burst incidence of 50 (T50) was calculated. sBRSfall was greater than sBRSrise (-6.24 ± 2.80 vs. -4.34 ± 2.16 bursts·100 heartbeats-1·mmHg-1, P = 0.01) and had a narrower operating range (14 ± 8 vs. 20 ± 10 mmHg, P = 0.01) that was shifted rightward (T50, 75 ± 9 and 70 ± 11 mmHg, P < 0.001). At diastolic pressures below baseline, sBRSfall was less than sBRSrise (-1.81 ± 1.31 vs. -3.59 ± 1.70 bursts·100 heartbeats-1·mmHg-1, P = 0.003) as low absolute pressures operated closer to the saturation plateau on the falling, compared with the rising pressure curve. At pressures above baseline, sBRSfall was greater than sBRSrise (-5.23 ± 1.94 and -3.79 ± 1.67 bursts·100 heartbeats-1·mmHg-1, P = 0.03). These findings demonstrate that the sympathetic arterial baroreflex possesses two response curves for processing beat-to-beat diastolic pressure falls and rises. The falling pressure curve is rightward shifted, which reduces sensitivity to falling pressure at low absolute pressures. This demonstrates that the direction of the hysteresis is influenced by the prevailing pressure level relative to each baroreflex response curve.NEW & NOTEWORTHY The findings show that the arterial baroreflex processes diastolic pressure dependent on the direction of pressure change from the previous beat, yielding two distinct baroreflex response curves to falling and rising pressure. Overall, the falling pressure curve is rightward shifted and more sensitive. The rightward shift caused a hysteresis reversal at hypotensive pressures as the falling pressure saturation plateau of the sigmoid response curve occurred at higher pressures than the rising pressure curve.

Arterial baroreflex regulation of muscle sympathetic single-unit activity in men: influence of resting blood pressure.

The arterial baroreflex has dominant control over multiunit muscle sympathetic nerve activity (MSNA) burst occurrence, but whether this extends to all single units or is influenced by resting blood pressure status is unclear. In 22 men (32 ± 8 yr), we assessed 68 MSNA single units during sequential bolus injections of nitroprusside and phenylephrine (modified Oxford). Sympathetic baroreflex sensitivity (sBRS) was quantified as the weighted negative linear regression slope between diastolic blood pressure (DBP) and single-unit spike firing probability and multiple spike firing. Strong negative linear relationships (r ≥ -0.50) between DBP and spike firing probability were observed in 63/68 (93%) single units (-2.27 ± 1.27%·cardiac cycle-1·mmHg-1 [operating range, 18 ± 8 mmHg]). In contrast, only 45/68 (66%) single units had strong DBP-multiple spike firing relationships (-0.13 ± 0.18 spikes·cardiac cycle-1·mmHg-1 [operating range, 14 ± 7 mmHg]). Participants with higher resting DBP (65 ± 3 vs. 77 ± 3 mmHg, P < 0.001) had similar spike firing probability sBRS (low vs. high, -2.08 ± 1.08 vs. -2.46 ± 1.42%·cardiac cycle-1·mmHg-1, P = 0.33), but a smaller sBRS operating range (20 ± 6 vs. 16 ± 9 mmHg, P = 0.01; 86 ± 24 vs. 52 ± 25% of total range, P < 0.001) and a higher proportion of single units without arterial baroreflex control outside this range [6/31 (19%) vs. 21/32 (66%), P < 0.001]. Participants with higher resting DBP also had fewer single units with arterial baroreflex control of multiple spike firing (79 vs. 53%, P = 0.04). The majority of MSNA single units demonstrate strong arterial baroreflex control over spike firing probability during pharmacological manipulation of blood pressure. Changes in single-unit sBRS operating range and control of multiple spike firing may represent altered sympathetic recruitment patterns associated with the early development of hypertension.NEW & NOTEWORTHY Muscle sympathetic single units can be differentially controlled during stress. In contrast, we demonstrate that 93% of single units maintain strong arterial baroreflex control during pharmacological manipulation of blood pressure. Interestingly, the operating range and proportion of single units that lose arterial baroreflex control outside of this range are influenced by resting blood pressure levels. Altered single unit, but not multiunit, arterial baroreflex control may represent changes in sympathetic recruitment patterns in early stage development of hypertension.

Circulatory responses at the onset of handgrip exercise in patients with Parkinson's disease.

NEW FINDINGS: What is the central question of this study? The initial circulatory response to isometric exercise in young healthy subjects is thought to be cholinergically mediated. Do patients with Parkinson's disease, a specific population known to present cholinergic dysfunction, present impairment in these initial circulatory responses? What is the main finding and its importance? The initial reduction in total peripheral resistance was absent in patients with Parkinson's disease and in older subjects, which augmented the pressor response at the onset of isometric handgrip exercise. Given that cholinergic mechanisms play an important role in the circulatory responses at the onset of isometric exercise in humans, our data suggest that cholinergic mechanisms might be compromised with ageing. ABSTRACT: Physical exercise has been used as coping strategy for Parkinson's disease (PD). Thus, a better understanding of circulatory responses to exercise in this population is warranted. During the onset of isometric handgrip (IHG) exercise there is an increase in blood pressure (BP) and a reduction in the total peripheral resistance (TPR) in young subjects. This immediate reduction of TPR is thought to be mediated by a cholinergic mechanism. Given that PD also affects cholinergic neurons, we hypothesized that patients with PD would present blunted circulatory responses at the onset of IHG exercise. Mean BP, stroke volume, heart rate, cardiac output and TPR were measured during performance of 20 s of IHG at 40% maximal voluntary contraction in 12 patients with PD (66 ± 2 years old, 171 ± 7 cm, 74 ± 7 kg), 11 older subjects (65 ± 9 years old, 171 ± 7 cm, 74 ± 10 kg) and 10 young subjects (21 ± 1 years old, 178 ± 6 cm, 79 ± 9 kg). Isometric handgrip elicited an augmented BP increase in patients with PD and older subjects at 10 and 20 s compared with young subjects. However, the BP augmentation was lower at 20 s in patients with PD. The IHG-induced reduction in TPR was attenuated in patients with PD and older subjects compared with young subjects. Our results show that the circulatory responses at the onset of IHG are impaired in patients with PD and older subjects. Overall, these findings suggest that the cholinergic mechanism might be compromised with ageing.

Experience of treatment of prosthetic valve endocarditis: a retrospective single-center cross-sectional study.

BACKGROUND: The aim of this study was to describe the experience of treatment of early prosthetic valve endocarditis at a heart center. DESIGN AND SETTING: Retrospective single-center study on data collected from electronic medical records covering the period from January 2009 to December 2015. METHODS: Over the study period, 1,557 consecutive valve operations were performed on adult patients. The study population comprised 32 patients (2%) who were diagnosed with prosthetic valve endocarditis within 12 months after the index surgery. Medical records were retrieved from electronic hospital records, retrospectively. Descriptive clinical, echocardiographic, microbiological and treatment-type data were used. Risk factors for early mortality were studied through univariate and multivariate analyses. RESULTS: The main clinical manifestation of infective endocarditis was fever, and this was present in all patients. Most of the prostheses were affected in the aortic position (40.6% of cases). The most commonly cultured microorganisms were Staphylococcus epidermidis and Staphylococcus aureus. Twenty-six patients (81.3%) underwent surgical treatment and six (18.7%) underwent exclusive clinical treatment. The prevalence of postoperative complications was 31.3% and hospital mortality occurred in seven cases (21.9%). The mortality rate was 50% among the patients who underwent medical treatment and 15.4% among those who underwent surgery. There were no independent risk factors for mortality. CONCLUSION: Prosthetic valve endocarditis is an infrequent complication of valve replacement. Surgical treatment has mortality rates compatible with the severity of patients' conditions. Surgical indication should not be delayed when clinical treatment has been ineffective.

Experience of treatment of prosthetic valve endocarditis: a retrospective single-center cross-sectional study

ABSTRACT BACKGROUND: The aim of this study was to describe the experience of treatment of early prosthetic valve endocarditis at a heart center. DESIGN AND SETTING: Retrospective single-center study on data collected from electronic medical records covering the period from January 2009 to December 2015. METHODS: Over the study period, 1,557 consecutive valve operations were performed on adult patients. The study population comprised 32 patients (2%) who were diagnosed with prosthetic valve endocarditis within 12 months after the index surgery. Medical records were retrieved from electronic hospital records, retrospectively. Descriptive clinical, echocardiographic, microbiological and treatment-type data were used. Risk factors for early mortality were studied through univariate and multivariate analyses. RESULTS: The main clinical manifestation of infective endocarditis was fever, and this was present in all patients. Most of the prostheses were affected in the aortic position (40.6% of cases). The most commonly cultured microorganisms were Staphylococcus epidermidis and Staphylococcus aureus. Twenty-six patients (81.3%) underwent surgical treatment and six (18.7%) underwent exclusive clinical treatment. The prevalence of postoperative complications was 31.3% and hospital mortality occurred in seven cases (21.9%). The mortality rate was 50% among the patients who underwent medical treatment and 15.4% among those who underwent surgery. There were no independent risk factors for mortality. CONCLUSION: Prosthetic valve endocarditis is an infrequent complication of valve replacement. Surgical treatment has mortality rates compatible with the severity of patients' conditions. Surgical indication should not be delayed when clinical treatment has been ineffective

Consenso sobre Ecocardiografia transesofágica perioperatória da Sociedade Brasileira de Anestiologia e do Departamento de Imagem Cardiovascular da Sociedade Brasileira de Cardiologia / Consensus on perioperative transesophageal echocardiography of the Brazilian Society of Anesthesiology and the Department of Cardiovascular Image of the Brazilian Society of Cardiology

A Sociedade Brasileira de Anestesiologia, pelo Núcleo Vida de Ecocardiografia Transesofágica Intraoperatória (ETTI/SBA) juntamente com o Departamento de Imagem Cardiovascular da Sociedade Brasileira de Cardiologia (DIC/SBC), fez uma força-tarefa para normatizar a feitura da ecocardiografia transesofágica intraoperatória para os anestesiologistas e ecocardiografistas brasileiros com base nas evidências científicas da Sociedade dos Anestesiologistas Cardiovasculares/Sociedade Americana de Ecocardiografia (SCA/ASE) e da Sociedade Brasileira de Cardiologia

Blunted cardiovascular responses to exercise in Parkinson's disease patients: role of the muscle metaboreflex.

Patients with Parkinson's disease (PD) exhibit attenuated cardiovascular responses to exercise. The underlying mechanisms that are potentially contributing to these impairments are not fully understood. Therefore, we sought to test the hypothesis that patients with PD exhibit blunted cardiovascular responses to isolated muscle metaboreflex activation following exercise. For this, mean blood pressure, cardiac output, and total peripheral resistance were measured using finger photoplethysmography and the Modelflow method in 11 patients with PD [66 ± 2 yr; Hoehn and Yahr score: 2 ± 1 a.u.; time since diagnosis: 7 ± 1 yr; means ± SD) and 9 age-matched controls (66 ± 3 yr). Measurements were obtained at rest, during isometric handgrip exercise performed at 40% maximal voluntary contraction, and during postexercise ischemia. Also, a cold pressor test was assessed to confirm that blunted cardiovascular responses were specific to exercise and not representative of generalized sympathetic responsiveness. Changes in mean blood pressure were attenuated in patients with PD during handgrip (PD: ∆25 ± 2 mmHg vs. controls: ∆31 ± 3 mmHg; P < 0.05), and these group differences remained during postexercise ischemia (∆17 ± 1 mmHg vs. ∆26 ± 1 mmHg, respectively; P < 0.01). Additionally, changes in total peripheral resistance were attenuated during exercise and postexercise ischemia, indicating blunted reflex vasoconstriction in patients with PD. Responses to cold pressor test did not differ between groups, suggesting no group differences in generalized sympathetic responsiveness. Our results support the concept that attenuated cardiovascular responses to exercise observed in patients with PD are, at least in part, explained by an altered skeletal muscle metaboreflex. NEW & NOTEWORTHY Patients with Parkinson's disease (PD) presented blunted cardiovascular responses to exercise. We showed that cardiovascular response evoked by the metabolic component of the exercise pressor reflex is blunted in patients with PD. Furthermore, patients with PD presented similar pressor response during the cold pressor test compared with age-matched controls. Altogether, our results support the hypothesis that attenuated cardiovascular responses to exercise observed in patients with PD are mediate by an altered skeletal muscle metaboreflex.

Cholesterol efflux capacity does not associate with coronary calcium, plaque vulnerability, and telomere length in healthy octogenarians.

Several studies have revealed that traditional risk factors are less effective in predicting CVD risk in the elderly, suggesting the need to identify new biomarkers. Here, we evaluated the association between serum cholesterol efflux capacity (CEC), an atheroprotective property of HDL recently identified as a novel marker of CVD risk, and atherosclerotic burden in a cohort of very old, healthy individuals. Serum CEC values were not significantly correlated either with calcium score or with markers of vulnerable plaque, such as positive remodeling, hypodensity, spotty calcification, or napking-ring sign. In addition, no association was detected between CEC and telomere length, a marker of biological aging that has been linked to atherosclerosis extent. Interestingly, elderly subjects presented a remarkably higher CEC (+30.2%; P < 0.0001) compared with values obtained from a cohort of sex-matched, cardiovascular event-free, middle-aged individuals. In conclusion, serum CEC is not related to traditional risk factors in very old, cardiovascular event-free subjects, but has significantly higher values compared with a healthy, younger population. Whether this improved HDL functionality may represent a protective factor in CVD onset must be established in future studies.

Consenso sobre Ecocardiografia Transesofágica Perioperatória da Sociedade Brasileira de Anestesiologia e do Departamento de Imagem Cardiovascular da Sociedade Brasileira de Cardiologia / Consensus on Perioperative Transesophageal Echocardiography of the BrazilianSociety of Anesthesiology and the Department of Cardiovascular Image of theBrazilian Society of Cardiology

RESUMO A Sociedade Brasileira de Anestesiologia, pelo Núcleo Vida de Ecocardiografia Transe-sofágica Intraoperatória (ETTI/SBA) juntamente com o Departamento de Imagem Cardiovascularda Sociedade Brasileira de Cardiologia (DIC/SBC), fez uma forc ̧a-tarefa para normatizar afeitura da ecocardiografia transesofágica intraoperatória para os anestesiologistas e ecocar-diografistas brasileiros com base nas evidências científicas da Sociedade dos AnestesiologistasCardiovasculares/Sociedade Americana de Ecocardiografia (SCA/ASE) e da Sociedade Brasileirade Cardiologia.

ABSTRACT Through the Life Cycle of Intraoperative Transesophageal Echocardiography(ETTI/SBA) the Brazilian Society of Anesthesiology, together with the Department of Cardi-ovascular Image of the Brazilian Society of Cardiology (DIC/SBC), createded a task force tostandardize the use of intraoperative transesophageal echocardiography by Brazilian anesthesi-ologists and echocardiographers based on scientific evidence from the Society of CardiovascularAnesthesiologists/American Society of Echocardiography (SCA/ASE) and the Brazilian Society ofCardiology.

Consenso sobre Ecocardiografia Transesofágica Perioperatória da Sociedade Brasileira de Anestesiologia e do Departamento de Imagem Cardiovascular da Sociedade Brasileira de Cardiologia / Consensus on Perioperative Transesophageal Echocardiography of the BrazilianSociety of Anesthesiology and the Department of Cardiovascular Image of theBrazilian Society of Cardiology

RESUMO: A Sociedade Brasileira de Anestesiologia, pelo Núcleo Vida de Ecocardiografia Transesofágica Intraoperatória (ETTI/SBA) juntamente com o Departamento de Imagem Cardiovascular da Sociedade Brasileira de Cardiologia (DIC/SBC), fez uma força-tarefa para normatizar a feitura da ecocardiografia transesofágica intraoperatória para os anestesiologistas e ecocardiografistas brasileiros com base nas evidências científicas da Sociedade dos Anestesiologistas Cardiovasculares/Sociedade Americana de Ecocardiografia (SCA/ASE) e da Sociedade Brasileira de Cardiologia.

ABSTRACT: Through the Life Cycle of Intraoperative Transesophageal Echocardiography (ETTI/SBA) the Brazilian Society of Anesthesiology, together with the Department of Cardiovascular Image of the Brazilian Society of Cardiology (DIC/SBC), createded a task force to standardize the use of intraoperative transesophageal echocardiography by Brazilian anesthesiologists and echocardiographers based on scientific evidence from the Society of Cardiovascular Anesthesiologists/American Society of Echocardiography (SCA/ASE) and the Brazilian Society of Cardiology.

Sympathetically mediated cardiac responses to isolated muscle metaboreflex activation following exercise are modulated by body position in humans.

Isolated muscle metaboreflex activation with posthandgrip exercise ischemia (PEI) increases sympathetic nerve activity and partially maintains the exercise-induced increase in blood pressure, but a smaller heart rate (HR) response occurs. The cardiopulmonary baroreceptors, mechanically sensitive receptors that respond to changes in central blood volume and pressure, are strongly associated with changes in body position and upon activation elicit reflex sympathoinhibition. Here, we tested the hypothesis that postural changes modulate the sympathetically mediated cardiac response to PEI in humans. Beat-to-beat HR (electrocardiography) and blood pressure (finger photoplethysmography) were continuously measured, and cardiac function was assessed by echocardiography in 13 healthy men (21 ± 3 yr). After a 15-min rest period, 90-s static handgrip at 40% maximum voluntary contraction was performed followed by 3 min of PEI. Four trials were randomly conducted during either seated or supine position with and without ß1-adrenergic blockade (25 mg atenolol). During PEI under control conditions, HR remained elevated from baseline in the seated [change (Δ): 4 ± 1 beats/min] but not in the supine (change: -1 ± 1 beats/min) position. Similarly, stroke volume and cardiac output were increased from baseline in the seated (∆13.0 ± 2.4 ml and ∆1.1 ± 0.2 l/min, respectively) but not in the supine (∆2.5 ± 2.9 ml and ∆0.13 ± 0.20 l/min, respectively) position. During ß1-adrenergic blockade, HR, stroke volume, and cardiac output remained unchanged in both conditions. We conclude that sympathetically mediated cardiac responses to PEI are influenced by changes in body position. These findings indicated that muscle metaboreflex and cardiopulmonary baroreflex have an interactive influence on the neural control of cardiovascular function in humans. NEW & NOTEWORTHY In the present study, we demonstrated that muscle metaboreflex activation increases heart rate, stroke volume, and cardiac output in the seated position but not in the supine position and not after ß1-adrenergic blockade. These findings indicate that sympathetically mediated cardiac responses to isolated muscle metaboreflex activation after exercise are modulated by central blood volume mobilization.

[Consensus on Perioperative Transesophageal Echocardiography of the Brazilian Society of Anesthesiology and the Department of Cardiovascular Image of the Brazilian Society of Cardiology]. / Consenso sobre Ecocardiografia Transesofágica Perioperatória da Sociedade Brasileira de Anestesiologia e do Departamento de Imagem Cardiovascular da Sociedade Brasileira de Cardiologia.

Through the Life Cycle of Intraoperative Transesophageal Echocardiography (ETTI/SBA) the Brazilian Society of Anesthesiology, together with the Department of Cardiovascular Image of the Brazilian Society of Cardiology (DIC/SBC), createded a task force to standardize the use of intraoperative transesophageal echocardiography by Brazilian anesthesiologists and echocardiographers based on scientific evidence from the Society of Cardiovascular Anesthesiologists/American Society of Echocardiography (SCA/ASE) and the Brazilian Society of Cardiology.

TCF7L2 polymorphism is associated with low nitric oxide release, endothelial dysfunction and enhanced inflammatory response after myocardial infarction.

BACKGOUND: The favorable effects of insulin during myocardial infarction (MI) remain unclear due to the divergence between mechanistic studies and clinical trials of exogenous insulin administration. The rs7903146 polymorphism of the transcription factor 7-like 2 (TCF7L2) gene is associated with attenuated insulin secretion. METHODS: In non-diabetic patients with ST-elevation MI (STEMI), using such a model of genetically determined down-regulation of endogenous insulin secretion we investigated the change in plasma insulin, C-peptide, interleukin-2 (IL-2), C-reactive protein (CRP), and nitric oxide (NOx) levels between admission (D1) and the fifth day after MI (D5). Coronary angiography and flow-mediated dilation (FMD) were performed at admission and 30 days after MI, respectively. Homeostasis Model Assessment estimated insulin secretion (HOMA2%ß) and insulin sensitivity (HOMA2%S). RESULTS: Although glycemia did not differ between genotypes, carriers of the T-allele had lower HOMA2%ß and higher HOMA2%S at both D1 and D5. As compared with non-carriers, T-allele carriers had higher plasma IL-2 and CRP at D5, higher intracoronary thrombus grade, lower FMD and NOx change between D1 and D5 and higher 30-day mortality. CONCLUSION: In non-diabetic STEMI patients, the rs7903146 TCF7L2 gene polymorphism is associated with lower insulin secretion, worse endothelial function, higher coronary thrombotic burden, and higher short-term mortality. GENERAL SIGNIFICANCE: During the acute phase of MI, a lower capacity of insulin secretion may influence clinical outcome.

Genotyping the Mu-opioid receptor A118G polymorphism using the real-time amplification refractory mutation system: allele frequency distribution among Brazilians.

BACKGROUND: The mu-opioid receptor (OPRM1) A118G polymorphism has been associated with decreased analgesic effects of opioids and predisposition to addiction. However, its role in specific clinical scenarios and in different ethnicities must be better defined. No studies evaluating the A118G polymorphism in the Brazilian population have yet been published. METHODS: Genomic DNA was isolated from peripheral leukocytes of 200 surgical patients of the Center-West region of Brazil. Our genotyping protocol was developed based on the real-time amplification refractory mutation system and validated by comparison with cycle sequencing. Functional consequences of the A118G polymorphism were studied by comparing tobacco smoking prevalence and exposure between genotype groups. RESULTS: We observed perfect correlation between genotyping and sequencing results. Frequency of the G allele was 16% (IC 95% 12.7-19.9%) in our sample. Genotype distribution revealed 146 (73%) patients 118A homozygous, 44 (22%) heterozygous, and 10 (5%) homozygous for the G variant. After grouping patients according to the presence of the G allele, we did not observe differences in smoking prevalence; however, patients with one or two copies of the 118G allele reported higher tobacco exposure than patients 118A homozygous measured in pack-years (28.9 ± 12.5 vs. 21.5 ± 10.8, respectively, P = 0.02). CONCLUSIONS: We developed a fast and reliable genotyping method to identify the allele frequency distribution of the OPRM1 A118G polymorphism among patients from Center-West Brazil. Our preliminary results suggest functional consequences of the polymorphism on smoking behavior among Brazilians.

Parada cardíaca súbita em anestesia geral como a primeira manifestação da origem anômala de artéria coronária esquerda / Sudden cardiac arrest in general anesthesia as the first manifestation of anomalous origin of the left coronary artery / Parada cardíaca súbita en anestesia general como la primera manifestación del origen anómalo de arteria coronaria izquierda

JUSTIFICATIVA E OBJETIVOS: O relato de caso descreve uma situação rara e potencialmente fatal associada à administração de anestesia. Nosso objetivo foi discutir as causas de parada cardíaca súbita no período perioperatório em pacientes aparentemente saudáveis e a fisiopatologia das anomalias de origem das artérias coronárias como uma causa de parada cardíaca súbita. RELATO DE CASO: Uma mulher de 44 anos, sem sintomas prévios de doença coronariana ou arritmias, apresenta parada cardíaca súbita durante a instalação de anestesia geral em duas situações distintas. No primeiro episódio, a paciente apresentava-se com quadro de abdômen agudo, porém hemodinamicamente estável. Após a indução anestésica, ocorreu bradicardia e hipotensão arterial, refratárias à reposição de volume e vasopressores. O quadro evoluiu para assistolia. A paciente foi reanimada com sucesso e recebeu alta em boas condições. No segundo episódio, um ano após o primeiro, a paciente se encontrava em boas condições clínicas para feitura de uma cirurgia eletiva. Após a indução anestésica, a paciente desenvolveu taquicardia ventricular seguida por assistolia, que foi prontamente revertida. Após extensa investigação, foi identificada uma origem anômala da artéria coronária esquerda. CONCLUSÕES: Nosso relato é ilustrativo ao enfatizar que uma investigação diagnóstica minuciosa deve ser feita nos casos de parada cardíaca súbita perioperatória, mesmo em pacientes aparentemente saudáveis.

BACKGROUND AND OBJECTIVES: This case report describes a rare and potentially fatal condition associated with anesthesia administration. Our aim was to discuss the causes of sudden cardiac arrest during the perioperative period in apparently healthy patients and the pathophysiology of anomalous origin of the coronary arteries as a cause of sudden cardiac arrest. CASE REPORT: Female patient, 44 years old, with no previous symptoms of heart disease or arrhythmias, had a sudden cardiac arrest during general anesthesia in two different situations. In the first episode, the patient presented signs of acute abdomen, but remained hemodynamically stable. Following induction of anesthesia, the patient exhibited bradycardia and hypotension refractory to volume replacement and vasopressors. The condition progressed to asystole. The patient was successfully resuscitated and discharged from the hospital in good condition. In the second episode, one year after the first, the patient was in good clinical condition to undergo an elective surgery. After induction of anesthesia, the patient developed ventricular tachycardia followed by asystole, which was promptly reversed. After extensive investigation, an anomalous origin of the left coronary artery was identified. CONCLUSIONS: Our report is illustrative as it emphasizes that a thorough diagnostic investigation should be done in cases of sudden cardiac arrest during the perioperative period, even in patients that appear to be healthy.

JUSTIFICATIVA Y OBJETIVOS: El relato de caso describe una situación rara y potencialmente fatal asociada con la administración de anestesia. Nuestro objetivo fue discutir las causas de parada cardíaca súbita en el período perioperatorio en pacientes aparentemente sanos y la fisiopatología de las anomalías de origen de las arterias coronarias como una causa de parada cardíaca súbita. RELATO DE CASO: Mujer de 44 años, sin sintomatología anterior de enfermedad coronaria o arritmias, que presenta una parada cardíaca súbita durante la aplicación de la anestesia general en dos situaciones distintas. En el primer episodio, la paciente tenía un cuadro de abdomen agudo pero hemodinámicamente estable. Después de la inducción anestésica, ocurrió una bradicardia e hipotensión arterial, refractarias a la reposición de volumen y vasopresores. El cuadro evolucionó con asistolia. La paciente fue reanimada con éxito y recibió alta en buenas condiciones. En el segundo episodio, un año después del primero, la paciente estaba en buenas condiciones clínicas para la realización de una cirugía electiva. Después de la inducción anestésica, desarrolló una taquicardia ventricular seguida por asistolia, que fue rápidamente revertida. Después de una extensa investigación, fue identificado un origen anómalo de la arteria coronaria izquierda. CONCLUSIONES: Nuestro relato es ilustrativo porque enfatiza que una investigación diagnóstica minuciosa debe ser realizada en los casos de parada cardíaca súbita perioperatoria, incluso en los pacientes aparentemente sanos.

Sudden cardiac arrest in general anesthesia as the first manifestation of anomalous origin of the left coronary artery.

BACKGROUND AND OBJECTIVES: This case report describes a rare and potentially fatal condition associated with anesthesia administration. Our aim was to discuss the causes of sudden cardiac arrest during the perioperative period in apparently healthy patients and the pathophysiology of anomalous origin of the coronary arteries as a cause of sudden cardiac arrest. CASE REPORT: Female patient, 44 years old, with no previous symptoms of heart disease or arrhythmias, had a sudden cardiac arrest during general anesthesia in two different situations. In the first episode, the patient presented signs of acute abdomen, but remained hemodynamically stable. Following induction of anesthesia, the patient exhibited bradycardia and hypotension refractory to volume replacement and vasopressors. The condition progressed to asystole. The patient was successfully resuscitated and discharged from the hospital in good condition. In the second episode, one year after the first, the patient was in good clinical condition to undergo an elective surgery. After induction of anesthesia, the patient developed ventricular tachycardia followed by asystole, which was promptly reversed. After extensive investigation, an anomalous origin of the left coronary artery was identified. CONCLUSIONS: Our report is illustrative as it emphasizes that a thorough diagnostic investigation should be done in cases of sudden cardiac arrest during the perioperative period, even in patients that appear to be healthy.