Cor triatriatum dexter y comunicación interauricular tipo seno venoso: Una asociación infrecuente / Cor triatriatum dexter and sinus venosus atrial septal defect: An infrequent association

RESUMEN El cor triatriatum es una malformación congénita poco frecuente, con una prevalecia de un 0,1% entre todas las anomalías congénitas cardíacas, donde el corazón queda dividido en tres atrios o aurículas. En el cor triatriatum dexter la aurícula derecha queda dividida, por una membrana fibromuscular, en dos partes, una proximal y otra distal, que se comunican o no entre sí. En la evolución natural de la enfemedad, los pacientes pueden permanecer asintomáticos hasta su diagnóstico o presentar manifectaciones cardiovasculares secundarias a insuficiencia cardíaca derecha y trastornos del ritmo. En el caso particular de aquellos que se encontraran sintomáticos, el tratamiento de elección sería la corrección quirúrgica del defecto y, en ocasiones, la rotura percutánea de la membrana; mientras que en los que se encuentran asintomáticos, el seguimiento y tratamiento oportuno de sus complicaciones parecería la alternativa más viable.

ABSTRACT Cor triatriatum is a rare congenital condition with a 0.1% prevalence among all cardiac congenital anomalies in which the heart is partitioned into three atria. In cor triatriatum dexter the right atrium is divided by a fibromuscular membrane into two parts, a proximal and a distal one, which may or may not communicate with each other. In the natural course of the condition, patients may remain asymptomatic until diagnosis or present with cardiovascular manifestations secondary to right heart failure and rhythm disorders. In the specific case of symptomatic patients, the treatment of choice would be surgical correction of the anomaly and sometimes percutaneous rupture of the membrane; while in asymptomatic patients, timely follow-up and treatment of their complications would seem to be the best alternatives.

Masa auricular derecha: la importancia del ecocardiograma al momento del diagnóstico de fibrilación auricular en el enfoque terapéutico / Right atrial mass: The importance of cardiac ultrasound at the time of diagnosis of atrial fibrillation in the therapeutic approach

Resumen Se presenta el caso de un varón de 70 años de edad, quien debutó con fibrilación auricular no valvular, en quien, dos meses después y mediante ecocardiografía, se objetivaron dos masas contiguas en la aurícula derecha. Las masas eran dependientes de la válvula de Eustaquio, alcanzaban el septo interauricular y se asemejaban a un mixoma. Ambas fueron resecadas mediante cirugía, sin complicaciones intraoperatorias ni postoperatorias. El estudio anatomo-patológico concluyó que eran compatibles con trombos sin componente tumoral. Durante el seguimiento permaneció asintomático y en ritmo de fibrilación auricular.

Abstract The case is presented on a 70 year-old male who debuted with non-valvular atrial fibrillation. Two months later, and using cardiac ultrasound, two contiguous masses were observed in the right atrium. The masses were hanging from the Eustachian (inferior vena cave) valve, reached the interatrial septum and resembled a myxoma. Both were surgically resected, with no intra- or post-operative complications. The patient remained asymptomatic and in atrial fibrillation rhythm during follow-up.

Valoración mediante ecocardiografía bidimensional del área y el volumen de la aurícula derecha indexados en el área de superficie corporal en población sana / Two-dimensional echocardiographic assessment of area and volume of the right atrium indexed to the body surface in a healthy population group

Objetivo: Determinar el área y el volumen normal de la aurícula derecha indexándola en la superficie corporal mediante ecocardiografía bidimensional en población sana para contar con estos valores como referente ante estudios futuros de población no sana. Metodología: Estudio observacional descriptivo. Resultados: Se incluyeron 64 pacientes sanos, entre los 17 y 68 años de edad, que cumplían los criterios de selección. El promedio de edad fue de 34 años (DE ± 12,19) y la razón de masculinidad fue de 1:1,78, encontrándose un promedio del área de la aurícula derecha calculado en 12,2 cm² (DE ± 1,46) con un mínimo observado en 10 cm² y un máximo de 16 cm². Además de esta medición, para esta cavidad se calculó el volumen, donde se observó un promedio de 28,7 mL, con un mínimo de 19 mL y un máximo de 42 mL (DE ± 5,19). Conclusiones: Este es el primer estudio en Colombia que reporta los valores normales indexados en el área de superficie corporal, del área y el volumen de la aurícula derecha en población sana.

Objective: To determine the area and normal volume of the right atrium indexing it to the body surface by means of a two-dimensional echocardiogram in a health population group in order to obtain the baseline values for future studies of unhealthy population groups. Methods: Descriptive observational study. Results: 64 healthy patients were included, aged 17 to 68, who fulfilled all selection criteria. The average age was 34 years old (SD ± 12.19) and the male:female ratio was of 1:1.78, finding an average right atrium area of 12.2 cm² (SD ± 1.46), a minimum of 10 cm² and a maximum of 16 cm². In addition to this measurement, for this cavity the volume was also calculated, where an average of 28.7 mL, with a minimum of 19 mL and a maximum of 42 mL (SD ± 5.19) was observed. Conclusions: This is the first study in Colombia to report normal values indexed to the body surface of the area and volume of the right atrium in a healthy population group.

Acurácia diagnóstica da onda P nas derivações de Lewis/Gallop para detecção das sobrecargas atriais / Diagnostic accuracy of the P wave in the Lewis and Gallop Leads for atrial enlargement detection

Fundamentos: A acurácia diagnóstica (AD) do eletrocardiograma (ECG) convencional para detecção das sobrecargas atriais (SA) é baixa. As derivações de Lewis (L) e Gallop (G) permitem melhor visualização da onda P no ECG. Objetivo: Verificar se os parâmetros da onda P nas derivações de Lewis e Gallop aumentam a acurácia diagnósticados critérios de SA do ECG convencional. Métodos: As características da onda P nas derivações de L e G foram padronizadas em 27 indivíduos saudáveis. Considerou-se como limite de normalidade o percentil 99 para esses parâmetros. Esses novos critérios foram avaliados em 117 pacientes através do ECG convencional e das derivações de L e G. As dimensões dos átrios pelo ecocardiograma foram consideradas padrão-ouro para definição das SA. Para determinação da AD de cada parâmetro utilizou-se a área sob a curva (AUC) ROC (receiver operating characteristic). Resultados: ECG convencional apresentou baixa AD para detecção das SA. O índice de Morris foi o único que mostrou AD significativa: AUC 0,57 (95%IC: 0,48-0,66); p=0,03. A inclusão da onda P>100 ms (L e G) não aumentou a AD para detecção de SA esquerda em relação aos critérios tradicionais: AUC 0,58 (95%IC: 0,50-0,65)vs. AUC 0,57 (95%IC: 0,49-0,65); p=0,80. A inclusão de onda P com amplitude >2mm (L) e/ou >3mm (G) tambémnão aumentou a AD para detecção de SA direita: AUC 0,53 (95%IC: 0,46-0,61) vs. AUC 0,53 (95%IC: 0,45-0,60); p=0,31.Conclusão: A inclusão da avaliação da onda P nas derivações acessórias de L e G não resultou em incremento da AD para detecção das SA.

Background: The diagnostic accuracy (DA) of the conventional electrocardiogram (ECG) for detecting atrial enlargement (AE) is low. Lewis (L) and Gallop (G) enable better viewing the P wave in the ECG.Objective: Checking whether the P wave parameters in the leads of Lewis and Gallop increase the diagnostic accuracy of the conventional ECG AE criteria. Methods: The P wave characteristics in the L and G leads were standardized in 27 healthy individuals. The percentile of 99 was considered as limit of normality for those parameters. These new criteria were evaluated in 117 patients through conventional ECG and the L and G leads. The atrial sizes under the echocardiogram were considered as golden standard for defining the AE. The areaunder the ROC (receiver operating characteristic) curve (AUC) was used for determining the DA of each parameter.Results: Conventional ECG presented low DA for detecting the AE. Morris index was the only showing significant DA: AUC 0.57 (95%CI:0.48-0.66); p=0.03. The inclusion of the P wave >100ms (L and G) has not increased the DA for detecting left AE compared to the traditional criteria: AUC 0.58 (95%CI: 0.50-0.65) vs. AUC 0.57 (95%CI: 0.49-0.65); p=0.80. Including P wave with amplitude >2 mm (L) and/or>3 mm (G) has not increased DA for detecting right AE either: AUC 0.53 (95%CI: 0.46-0.61) vs. AUC 0.53 (95%CI: 0.45-0.60); p=0.31. Conclusion: Including the P wave in the accessory leads of L and G did not result in increment of DA for detecting AE.

Cambios agudos en la función auricular derecha post uso de iloprost inhalatorio en pacientes con hipertensión arterial pulmonar: estudio con técnicas de deformación de imagen / Acute changes in right atrial funcion after Iloprost inhalation in patients with pulmonary hypertension: a study using image deformation techniques

Introducción: El efecto de prostanoides inhalatorios sobre la función auricular derecha (AD) en hipertensión arterial idiopática (HAP) no ha sido estudiado. Objetivo: Evaluar cambios agudos en la función AD y función diastólica del ventrículo derecho en pacientes con HAP post uso de Iloprost inhalatorio. Métodos: Se incluyeron pacientes con HAP sin uso previo de prostanoides. Se realizó un ecocardiograma transtorácico basal y 30 min posterior a la inhalación de iloprost. Se midió dimensión AD, relación E/e' y strain de la AD por speckle tracking, registrando la onda negativa de contracción auricular (SaAD) y la onda positiva de la fase de reservorio (SsAD). Se midió el tiempo de inicio de la fase de reservorio AD durante el sístole ventricular. Resultados: Se estudiaron 16 pacientes (15 mujeres), con edad promedio 44 ± 7,8 años. Post Iloprost disminuyó el volumen AD (basal: 140ml, post Iloprost: 109 ml; p 0,008) y las presiones de llenado (E/e’ basal: 13, post Iloprost: 9,8; p 0,028). No se registraron diferencias en el SaAD (basal: -8,4%, post Iloprost: -8,5%; p 0,834). El SsAD fue mayor post Iloprost (basal: 8,6%, post Iloprost: 11,7%; p 0,002) iniciándose antes durante el sístole ventricular (basal: 445ms, post Iloprost: 368ms; p 0,001). Conclusión: Con Iloprost inhalatorio en pacientes con HAP se observa una reducción aguda en el tamaño de la AD y en las presiones de llenado del VD. La deformación durante la fase de reservorio de la AD aumenta y se inicia significativamente antes. Esto sugiere que el Iloprost podría mejorar en forma aguda el trabajo mecánico de la AD en paciente con HAP.

Background: The effects of inhaled prostanoids on right atrial (RA) function in patients with Pulmonary Arterial Hypertension (PAH) have not been studied. We evaluated acute changes in RA function and right ventricular diastolic function after inhaled iloprost. Methods: We included PAH patients without prior prostanoid treatment. A surface echocardiogram was performed at baseline and 30 minutes after iloprost inhalation. Measurements included RA dimensions, right E/e’ ratio and RA strain by speckle tracking, registering a RA contraction wave (RASa) and RA reservoir wave (RASs). RA time to peak of deformation during the reservoir phase was also measured. Results: We included 16 patients (15 females, aged 44±7.8 years. Post iloprost there was a reduction in RA volume (baseline: 140ml, post iloprost: 109ml; p 0.008) and right ventricular filling pressure (baseline E/e’: 13, post iloprost: 9.8; p 0.028). There was no difference in the magnitude of the RASa wave (baseline: -8.4%, post iloprost: -8.5%; p 0.834). The RASs wave was larger post iloprost (baseline: 8.6%, post iloprost: 11.7%; p 0.002), and began earlier (baseline RA time to peak of deformation during reservoir phase: 445ms, post iloprost: 368ms; p 0.001). Conclusion: Inhaled iloprost acutely reduces RA size and right ventricular filling pressure in patients with HAP It also significantly increases the magnitude of RA systolic deformation as well as making it occur earlier in RA filling phase. This suggests that iloprost might improve RA mechanical performance.

Characteristics of Pulmonary Vein Enlargement in Non-Valvular Atrial Fibrillation Patients with Stroke

PURPOSE: The association between pulmonary vein (PV) dilatation and stroke in non-valvular atrial fibrillation (AF) patients remains unknown. MATERIALS AND METHODS: We examined the left atrium (LA) and PV in control (n=138) and non-valvular AF patients without (AF group, n=138) and with non-hemorrhagic stroke (AF with stroke group, n=138) using computed tomography. RESULTS: The LA, LA appendage (LAA), and all PVs were larger in the AF than control patients. The orifice areas of the LAA (5.6+/-2.2 cm2 vs. 4.7+/-1.7 cm2, p<0.001), left superior PV (3.8+/-1.5 cm2 vs. 3.4+/-1.2 cm2, p=0.019), and inferior PV (2.3+/-1.0 cm2 vs. 1.8+/-0.7 cm2, p<0.001) were larger in the AF with stroke than in the AF only group. However, right PVs were not different between the two groups. In a multivariate analysis, the orifice areas of the left superior PV [odds ratio (OR) 1.25, 95% confidence interval (CI) 1.03-1.51, p=0.02], left inferior PV (OR 1.97, 95% CI 1.41-2.75, p<0.001), and LAA (OR 1.30, 95% CI 1.13-1.50, p<0.001) were independent predictors of stroke. CONCLUSION: Compared to the right PVs, the left PVs and LAA exhibited more significant enlargement in patients with AF and stroke than in patients with AF only. This finding suggests that the remodeling of left-sided LA structures might be related to stroke.

Isolated dilatation of the inferior vena cava

The diameter and collapsibility of the inferior vena cava (IVC) should be interpreted in consideration with other clinical and echocardiographic parameters before drawing definitive diagnostic conclusions. We report a case of a 46-year-old female with isolated IVC dilation and diminished inspiratory collapse without other abnormalities, and provide a brief review of the literature.

Elevación diafragmática con colapso de la aurícula derecha y síntomas de falla cardíaca: reporte de un caso / Diaphragmatic elevation with collapse of the right atrium and symptoms of heart failure: a case report

La elevación diafragmática es una entidad caracterizada por la alteración en la fuerza contráctil de las fibras musculares del diafragma, que conlleva prolapso de las estructuras abdominales hacia la cavidad torácica. En la mayoría de los casos, los síntomas se presentan por la compresión del parénquima pulmonar subyacente; la compresión de estructuras cardíacas es menos frecuente. Se reporta el caso de una paciente que presentó signos y síntomas compatibles con falla cardíaca derecha y en quien los diferentes estudios demostraron una elevación diafragmática con colapso de la aurícula derecha como causa de su sintomatología.

Diaphragmatic elevation is a disorder characterized by impaired contractile force of the muscle fibers of the diaphragm, which results in prolapse of abdominal structures into the chest cavity. In most cases, symptoms occur by the underlying lung parenchyma compression. The compression of cardiac structures is less frequent. We report the case of a female patient who developed signs and symptoms consistent with right heart failure and in whom several studies showed a diaphragmatic elevation with collapse of the right atrium as cause of her symptomatology.

Análise comparativa entre a vascularização ventricular e do nó sinoatrial em gatos / Comparative analysis between ventricular and sinoatrial node vascularization in cats

A possível existência de interdependência na nutrição de territórios atriais e ventriculares tem sido objeto de preocupação por partes dos cardiologistas, especialmente no que tange a vascularização do nó sinoatrial e sua dependência apenas de uma artéria coronária ou de ambas e de sua relação com o predomínio destes vasos na vascularização ventricular. Assim, este estudo objetiva avaliar a relação da irrigação do nó sinoatrial e a origem e a predominância das artérias coronárias na vascularização dos ventrículos, para tanto utilizou-se 30 corações de gatos sem raça definida adultos, machos e fêmeas, sem sinais de afecção cardíaca. Os corações foram injetados pela aorta torácica com Neoprene Latex 450, corados com pigmento vermelho e dissecados posteriormente. Verificou-se que quando ocorria predomínio da vascularização ventricular do tipo esquerda (63,34 por cento) a irrigação do nó sinoatrial ficou predominantemente na dependência do ramo proximal atrial direito (78,9 por cento) ou com menor freqüência pelo ramo proximal atrial esquerdo (21,1 por cento). Na vascularização ventricular do tipo equilibrada (33,34 por cento), a irrigação do sinoatrial ficou na dependência mais freqüentemente do ramo proximal atrial direito (80 por cento), ou com menor freqüência a nutrição do nó se deu pelo ramo proximal atrial esquerdo (20 por cento). Em um caso isolado, ocorreu a vascularização ventricular do tipo direita (3,34 por cento), a nutrição do sinoatrial, ficou na dependência exclusiva do ramo intermédio atrial direito. Estes resultados indicam que nesta espécie não existe relação entre a irrigação do nó sinoatrial e o tipo de vascularização ventricular, independentemente do sexo.

The possible existence of interdependence in the blood nutrition of both atrial and ventricular territories has been a subject of concern to cardiologists, mainly related to vascularization of the sinoatrial node and its dependence on just one coronary artery or both, and its relation with the predominance of these vessels in the ventricular vascularization. Therefore, this research aimed evaluated the relation of blood irrigation of the sinoatrial node in relation to the coronary artery predominance in the ventricle vascularization. In doing so, we analyzed 30 hearts of cats without pedigree, males and females, adults of several ages. They were not carrying any heart problems. The hearts were injected by the thoracic aorta with Neoprene Latex 450, stained with red pigment, and then they were dissected. It was found that when there was a prevalence of ventricular vascularization of the left type (63.34 percent) the sinoatrial node irrigation was predominantly in the dependency of the Ramus proximalis atrii dextri (78.9 percent) or with less frequency by Ramus proximalis atrii sinister (21.1 percent). In the ventricular vascularization of the balanced type (33.34 percent), the pacemaker irrigation was in dependence more often of Ramus proximalis atrii dextri (80 percent) or with less frequency the nutrition of the sinoatrial node occurred by Ramus proximalis atril sinister (20 percent). In a single-case, we observed the ventricular vascularization of the right type (3.34 percent), the pacemaker nutrition was in an exclusive dependence of the Ramus intermedius atril dextri. These results suggest in this species there is no relationship between both the sinoatrial node irrigation and the type of ventricular vascularization, regardless of gender.

Restitution of atrial repolarization and atrial fibrillation in canine atrium / 中华心血管病杂志

<p><b>OBJECTIVE</b>Electrical restitution was believed to be a determinant responsible for the stability of heart rhythm. Although numerous studies focused on the role of action potential duration restitution (APDR) in the initiation and maintenance of ventricular fibrillation (VF), the relationship between atrial APDR and atrial fibrillation (AF) has not been fully understood. This study aims to investigate the characteristics of APDR of left atrium (LA) and right atrium (Rs) in canines and the relevance to induction of AF.</p><p><b>METHODS</b>Monophasic action potential (MAP) was recorded from LA and RA in 14 canines using the MAP recording-pacing combination catheter. APDR, plotted as action potential duration (APD) on the preceding diastolic interval (DI), was assessed by use of programmed stimulation with a single extrastimulus (S1S2) at LA and RA. Episodes of AF were recorded and analyzed.</p><p><b>RESULTS</b>APD90 was significantly shorter in the LA than that in the RA [(157.4 +/- 43.5) ms vs. (170.9 +/- 37.9) ms, P < 0.05]. The mean slope of the APDR curve by S1S2 in the LA was significantly greater than that in the RA (1.3 +/- 0.4 vs. 0.9 +/- 0.3, P < 0.05). The incidence of induced AF was significantly higher in the LA than in the RA (11/18 vs. 7/18, P < 0.05).</p><p><b>CONCLUSIONS</b>The APDR and MAP characteristics are not uniform between atrium, which may be one of the important mechanisms responsible for the initiation of AF. Heterogeneity of APDR between LA and RA might create critical gradients or a dispersion of repolarization and substrate for re-entrant arrhythmias and vulnerability to AF.</p>

Atrial electrical, contractile and structural remodeling induced by short-term atrial tachycardia in a canine model / 中华心血管病杂志

<p><b>OBJECTIVE</b>To evaluate atrial remodeling induced by short term pacing in a canine model.</p><p><b>METHODS</b>Transvenous lead was inserted into the right atrial appendage of anesthetized mongrel dogs and paced for 5 hours at 450 bpm (n=12). Effective refractory period (ERP) and P-wave duration were measured before and post pacing and left ventricular pressure was monitored during the procedure. Echocardiography was performed to observe the presence or absence of spontaneous echo contrast and to assess the effect of rapid atrial pacing on atrial function. All measurements were obtained in sinus rhythm. Histology of the myocardium in left atrial trabeculae and appendages was examined by electron microscopy.</p><p><b>RESULTS</b>Compared to pre-pacing status, ERP was significantly reduced [(87.27 +/- 16.35) ms vs. (113.27 +/- 11.99) ms, P<0.01] at a cycle length of 300 ms, P-wave duration significantly increased [(56.09 +/- 8.62) ms vs. (52.09 +/- 7.63) ms, P<0.01], the peak velocity of atrial contraction significantly decreased [(48.92 +/- 10.80) cm/s vs. (59.25 +/- 9.37) cm/s, P<0.05] while heart rates and left ventricular pressure were not affected post five hours rapid atrial pacing. Pacing also induced significantly cellular ultrastructures changes including myofibrils loss, glycogen accumulation, mitochondria loss and swelling.</p><p><b>CONCLUSION</b>Short term pacing resulted in atrial electrical, contractile and structural remodeling.</p>

Regulation of cardiovascular functions during acute blood loss.

Sudden blood loss of moderate degree causes fall in blood pressure, which is compensated to certain extent by baroreceptor mediated rise in heart rate and vasoconstriction. In case of severe haemorrhage fall in blood pressure is accompanied by bradycardia indicating failure of baroreceptor mediated recovery in blood pressure. In such conditions partial recovery in the blood pressure with time is possible due to mechanisms other than baroreflex. Therefore, in the present study the regulation of cardiovascular functions on increasing severity of blood loss in the absence of any therapeutic intervention was examined to elucidate the mechanisms involved in the recovery of blood pressure under such conditions. Two groups of animals were studied: (a) In the first group (n = 10) 20% of the total blood volume loss was induced, (b) In the second group (n = 10) 35% of the total blood volume loss was induced. In both the groups cardiovascular parameters were evaluated for one hour after the induction of haemorrhage to record any recovery due to natural compensatory mechanisms. In both the groups there was a significant fall in mean arterial pressure, cardiac output, stroke volume, right atrial pressure and base deficit. A significant increase in heart rate and total peripheral resistance was produced after 1 min of haemorrhage in 20% blood loss while a fall in total peripheral resistance and no rise in heart rate was produced after 35% blood loss. There was a recovery in cardiac output and mean arterial pressure with time in both the cases of blood loss. While a rise in heart rate and stroke volume was produced in 20% blood loss however an initial increase in stroke volume alone and later rise in heart rate alone was produced during recovery phase in 35% blood loss. These finding suggest that 20% blood loss is compensated by baroreflex while 35% blood loss is not accompanied by tachycardia so mechanisms other than the baroreflex, like increase in the vagal tone, contribute to the initial recovery in blood pressure and cardiac output.

Left and right atrial appendage function in patients with chronic atrial fibrillation

Transoesophageal echocardiography [TEE] has been shown to be a useful technique for assessing left atrial appendage [LAA] function by measuring LAA flow velocities. Recently, right atrial appendage [RAA] thrombi and depressed RAA function have been reported in patients with atrial fibrillation [AF]. To assess right atrial appendage flow and its possible relationship to left atrial appendage flow in patients with chronic AF; also to assess RAA function and its relation to early detection of new right atrial thrombi. This study included 90 patients presenting to the National Heart Institute and to Mataria Teaching Hospital for cardiovascular assessment by TEE: 40 patients with chronic non valvular AF, 40 patients with chronic valvular AF and 10 normal individuals acting as controls. All patients included in the study were subjected to the following: careful history taking, complete clinical examination, resting 12 lead ECG, plain chest X-ray, transthoracic echocardiography [TTE] and transoesophageal echocardiography [TEE]. Patients with chronic nonvalvular AF were significantly older, and the duration of AF was significantly longer than those with chronic valvular AF. Patients with chronic nonvalvular AF had significantly larger RA and RAA area than those with chronic valvular AF. Patients with chronic valvular AF had larger LA and LAA area than those with chronic nonvalvular AF. RAA and LAA emptying velocities were both reduced in valvular and non-valvular AF patients. TEE showed that 15% of patients with chronic valvular AF had left atrial thrombus 10% of patients with non-valvular AF had atrial thrombus, while none of the controls showed atrial thrombosis. Left atrial spontaneous echo contrast [SEC] was shown in 80% of chronic valvular AF and in 35% of chronic non-valvular AF, while right atrial SEC was shown in 25% of all patients. Our findings suggest that AF can affect both atria equally in nonvalvular AF, in contrast to valvular AF which affects the left atrium only. Therefore, the assessment of RAA and LAA function as well as atrial SEC may be important in patients with chronic nonvalvular AF and are especially so as predictors to intra-atrial thrombosis

Experimental study on early escharectomy after major burns in minipigs / 中华烧伤杂志

<p><b>OBJECTIVE</b>To investigate optimal time for early escharectomy after severe scald in minipigs.</p><p><b>METHODS</b>Minipigs inflicted with 35% TBSA full thickness burn were employed in the study, and they were randomly divided into A (n = 7, with escharectomy at 6PSH), and B (n = 7, with escharectomy at 24 PSH) groups. The hemodynamics indices, hemorrheology, and the serum levels of cytokines in the two groups were determined before burns and at 6, 8, 16, 24 and 72PSH.</p><p><b>RESULTS</b>The hemodynamics indices in A group obviously improved compared with those in B group. The cardiac output (CO, 2.28 +/- 0.03 L/min) and right arterial pressure (RAP, 4.54 +/- 0.04 mmHg) in A group recovered to the pre-injury levels at 48 PSH. There was no difference of the hemorrheology indices between the two groups (P > 0.05). The serum contents of cytokines in A group declined to the pre-injury level on 1 PBW, while those in B group were significantly higher than those before injury and those in A group (P < 0.05 or P > 0.01).</p><p><b>CONCLUSION</b>Escharectomy during 6 PBH might be safe and feasible, thus preventing long-term complications effectively.</p>

Role of PCO2 and pH measurements sampled from the right atrial cavity via the central venous catheter in open heart surgery

CO2 and W produced in tissus come into venous blood. Can PCO2 and pH sampled from the right atrial blood via a central venous catether approriately replace the arterial PCO2 and pH in open hear surgery? Objectives: To evaluate the correlation and the agreement of PCO2 and of pH between the arterial and venous right atrial blood. Methods: Cross-over study with matched comparision, calculation of paired t test, coefficient of correlation r (Pearson), agreement (Bland-Altman). Results: Arterial-venous right atrial PC02: gradient-5.68 (+/-2.44), r = 0.92 and narrow agreement. Arterial-venous right atrial pH: gradient 0.04 (+/-0.02), r = 0.94 and narrow agreement. Conclusion: PCO2 and pH of the right atrial blood can safely replace the arterial PCO2 and pH in cardiac anesthesia and intensive care.

Non invasive measurement of right atrial pressure

The aim of this study was to evaluate the correlation between right atrial pressure [RAP] and tricuspid Doppler variables. Tricuspid Doppler profile was recorded immediately before hemodynamic RAP estimation in 30 consecutive patients undergoing right-side catheterization. The diastolic tricuspid flow was obtained from standard apical 4-chamber view at a speed 100 mm/s. mean age of the study population 48 +/- 12 years. 15 patients were in sinus rhythm and 15 had atrial fibrillation. There was no significant difference between both groups in their Doppler variables. Mean RAP 6 +/- 4.2 [range 2-20 mmHg]. Significant relation was found between RAP and several tricuspid flow parameters in all patients. However, by stepwise multivariate analysis acceleration rate of early tricuspid flow emerged as the sole independent predictor of RAP [r = 0.985 F = 592, P <0.0001]. The analysis led to the following equation: RAP = [0.017 x acceleration rate] - 1.03. Doppler-derived tricuspid flow is a simple, bedside means for estimating right atrial pressure

Sildenafil citrate [viagra] induced enhancement of right atrial contractility in isolated rat heart in vitro

The present study deals with the chronotropic effects of Sildenafil citrate [Viagra] on right atrial contracctility of mammalian isolated heart muscle. Effects of Sildenafil citrate on rat isolated heart in-vitro using right atrial samples, in comparison with nor-adrenaline, revealed that Sildenafil at 10[-7] M and above produced dose related increases in contractility. The maximum observed increase at 10[-4] M represented a 126% +/- 31% increase above control amplitude. Nor-adrenaline produced similar dose-related increases in contractility and was appoximately three times more potent than Sildenafil citrate. Dimaprit also produced similar responses to the Sildenafil but was less potent. These results indicated that rat responds to Sildenafil citrate, which increases contracility and enhances atrial automaticity, with sensitivity comparable to that for nor-adrenaline. The selective antagonism of the Sildenafil contractility response by cimetidine indicated that this response is mediated via histamine H [2]-receptors and not H [1] noradrenergic beta receptors. The involvement of histamine H [2]- receptors is confirmed by the similarity of the response to dimaprit. The production of spontaneous contractions by dimaprit further suggests that Sildenafil citrate-induced enhancement of atrial automaticity is mediated via modified histamine H [2]-receptors

Parálisis atrial persistente: reporte de 2 casos / Persistent atrial standstill: report of two cases

La parálisis atrial persistente es una rara condición clínica, caracterizada por ausencia de actividad eléctrica y mecánica del atrio, así como la incapacidad de responder a estímulos eléctricos. A partir de la introducción del mapeo intraatrial se logró demostrar la existencia de formas totales y parciales. Se presenta en tres grupos de pacientes: aquéllos con una enfermedad cardiaca de larga evolución, los portadores de algún tipo de distrofia muscular y los con formas aisladas. En la presente revisión se reportan dos casos. Uno, en el que se demostró parálisis atrial total asociado con cardiopatía dilatada. El segundo, con cardiopatía reumática inactiva, en el que se demostró parálisis atrial parcial, que incluyó sólo el tercio apical del atrio derecho. Se presenta el comportamiento clínico y electrofisiológico de ambos pacientes y se hace una revisión de los trabajos recientemente publicados en relación al tema

Restoration of Atrial Mechanical Function after Maze Operation

BACKGROUND: Maze operation is aimed for the restoration of sinus rhythm. But restoration of atrial mechanical function has not been demonstrated in all patients converted to sinus rhythm. METHOD: From Apr. 1994 to Feb. 1996, maze operations were performed in 32 pts (M:F=13:19, mean age 47.1+/-9.0 years) combined with valvular surgery(n=26), CABG(n=3), and others(n=3). Presence of atrial mechanical function was serially examined before discharge, in 3mo, 6mo and 1 yr using Doppler echocardiography. RESULTS: In 22 patients(pts), sinus rhythm was maintained without antiarrhythmic agents. In 4 patients antiarrhythmic agent was required to maintain sinus rhythm while in another 4 patients showed paroxysmal Af despite of the treatment with antiarrhythmic agents. In 30 pts with sinus rhythm or paroxysmal Af, right atrial function was restored in all pts while left atrial function was restored in only 19/30(63%). Peak A velocity and A/E ratio were 0.38+/-0.12m/s, 0.74, respectively on tricuspid inflow(TI), and 0.46+/-0.14m/s, 0.40, respectively on mitral inflow(MI ). MI peak A velocity and A/E ratio were significantly lower than the 16 control postoperative pts (0.75<0.29, 0.80 : p+/-0.01). In pts with atrial mechanical function, the duration of Af was significantly shorter than patients without atrial function (1.9+/-2.9 yr vs 7.1+/-3.0 yr : p<0.01), but no significant differences in the LA size and volume. CONCLUSION: Maze operation is effective in restoring sinus rhythm. But restoration of sinus rhythm was not always associated with restoration of atrial mechanical function, and the restored atrial function was incomplete. The duration of Af could be a markker for predicting the restoration of atrial function.