Left atrial appendage aneurysm with paroxysmal atrial fibrillation

Aneurysm of the left atrial appendage is extremely rare, and afflicted patients most commonly present with atrial tachyarrhythmia or thromboembolism. For these patients, resection of the aneurysm is the recommended and preferred therapy. We present the case of a 57-year-old woman who was found incidentally to have a large aneurysm of the left atrial appendage presenting as atrial fibrillation. After surgical intervention with resection of the aneurysm and a Cox maze III procedure, the patient recovered and was discharged in sinus rhythm.     

Giant right atrial aneurysm with atrial fibrillation

Congenital right atrial aneurysm is a rare condition. Here we reported a 16‐year‐old male with giant right atrial aneurysm, atrial fibrillation, and atrial septal defect. Surgical resection of extensive right atrium, ASD repair, and maze procedure were performed. In the present case, we found extensive enlargement of right atrium protruding to the apex on the surface of the right ventricle. With the exist of atrial fibrillation, thrombus formation was always a lethal threat. Surgical treatment can provide excellent clinical results and further avoided life‐threatening complications.     

A case of left atrial myxoma associated with atrial septal defect

Cardiac myxoma is the most frequent primary tumor of the heart. However, it is rarely associated with congenital cardiac anomalies such as atrial septal defect in the literature. We present a 72-year-old woman referred to the emergency department with loss of consciousness and finally diagnosed as a pedinculated mobile left atrial myxoma and concomitant occurrence of an ostium secundum type atrial septal defect. The mass was successfully excised, and atrial septal defect was safely repaired by primary suture. The patient is currently well after surgery. Atrial myxoma should be considered in the differential diagnosis when patients present with neurological consequences of systemic embolization.     

Histologic atrial myolysis is associated with atrial fibrillation after cardiac operation

BACKGROUND: Postoperative atrial fibrillation after cardiac operation is common. Despite the identification of risk factors associated with postoperative atrial fibrillation, the pathophysiologic mechanisms remain unclear. Myolysis has been recently described to be associated with maintenance of atrial fibrillation in experimental animals. In this study, we attempted to identify histopathologic changes in atria that might predict the development of postoperative atrial fibrillation, and specifically address its association with myolysis. METHODS: Right appendicular atrial tissue was sampled before and after cardiopulmonary bypass from 60 patients in sinus rhythm who underwent elective coronary artery bypass grafting. RESULTS: Fifteen patients (25%) developed postoperative atrial fibrillation. Histopathologic abnormalities were found in most patients (52 of 60). However, only myolysis and lipofuscin levels were found to be an independent histologic finding associated with the development of postoperative atrial fibrillation. Electron microscopy showed that myolytic vacuoles were not membrane bound, and were associated with lipofuscin deposits. Neither mitochondrial pathology nor apoptosis was detected in the atria before or after operation. CONCLUSIONS: Abnormalities in biopsies before cardiopulmonary bypass can indicate the susceptibility to develop postoperative atrial fibrillation. This implies that the status of the atrium before cardiopulmonary bypass is a major determinant in the development of this common complication.     

超声心动图预测心房颤动患者左心房血栓形成

心房颤动(房颤)可促进左心房血栓形成,而血栓脱落后引起的血栓栓塞是其最严重的并发症之一。准确预测房颤患者左心房血栓的形成,对房颤术前风险评估及临床抗凝治疗方案的选择有重要价值。超声心动图具有无创、经济等优点,可为预测房颤患者左心房血栓的形成提供可靠信息。     

Radiofrequency ablation of atrial flutter combined with closure of atrial septal defect

Radiofrequency ablation of atrial flutter combined with patch closure of an atrial septal defect is described. Radiofrequency energy was delivered in the cavo-tricuspid isthmus and from the inferior margin of the atriotomy down to the septal defect using a temperature-controlled multipolar radiofrequency catheter. In addition, cryolesions were applied to the junction of the ablation scar with the tricuspid annulus and with the ostium of the inferior vena cava. Sinus rhythm was restored and an electrophysiologic study conducted 2 months later confirmed the bidirectional conduction block of the cavo-tricuspid isthmus.     

Right atrial separation effect for chronic atrial fibrillation with atrial septal defect: report of four cases.

We operated on 56 adults diagnosed with atrial septal defect (ASD) between 1990 and 2004. Of these, eight had complications of atrial fibrillation (AF) in the preoperative period. After 1998, right atrial separation was performed in four cases. Marked improvement was noted in three out of the four cases. The right atrial separation procedure was a simple, easy, and effective method for the treatment of chronic AF associated with ASD.     

Left atrial myxoma with cerebral emboli

Infarction of the central nervous system secondary to embolism from left atrial myxoma is a recognized phenomenon. However, myxoma as the source of an embolus may be overlooked if an index of suspicion is not present during the evaluation of the patient with a stroke without a known cause. We present a case report that illustrates some of the pitfalls and characteristic findings present in the evaluation of these patients. The magnetic resonance image of multiple cerebral aneurysms and infarction associated with this condition is presented along with a unique, arteriographically proven resolution of a fusiform cerebral aneurysm after the removal of the cardiac tumor. A review of published case reports suggests that, if the cardiac tumor is recognized and treated quickly, the ultimate prognosis, while uncertain, is usually good. However, because the potential exists for recurrence of the cardiac tumor, for enlargement of the cerebral lesions, or for late development of cerebral lesions, long term follow-up is mandatory and a vigorous work-up must be pursued if the patient again becomes symptomatic or develops central nervous system manifestations for the first time.     

Securing atrial lines with Silastic ligatures

We present a safe and easy-to-apply method of securing monitoring atrial cannulae after pediatric cardiac operations. We used Silastic ligatures together with purse strings on the tip of the atrial appendages in more than 350 cases, in a 5-year period. We never reported malfunctioning during their use, and no bleeding or rupture complication was detected by echocardiographic control after withdrawal.     

Chronic atrial fibrillation: decreased actin expression in patients with chronic atrial fibrillation

AIM: Chronic atrial fibrillation (AF) is characterized by a severe contractile dysfunction and myolysis, which develops progressively. Myolysis and the remodelling of the cellular ultrastructure is associated with the replacement of sarcomeres by glycogen. The aim of our study was to determine if myolysis is characterized by a reduction in actin concentration. METHODS: Right atrial samples from 18 patients undergoing elective cardiac surgery were excised and immediately frozen in liquid nitrogen. Eight patients had chronic AF (>3 months) and 10 patients were in sinus rhythm (SR). Actin concentration was determined by sodium dodecyl sulfate-polycrylamide gel electrophoresis (SDS-PAGE), Western blot and quantified by optical densitometry. RESULTS: Immunoblot analysis demonstrated actin expression in all hearts. In myocardial samples from patients with chronic AF we found a 2.1 fold reduction in actin expression. (P<0.001) CONCLUSION: The decrease in actin concentration via myolysis, might decrease energy consumption and be an additional mechanism for contractile dysfunction in chronic AF.     

Giant left atrial ball thrombus in a patient with chronic nonvalvular atrial fibrillation

A 56-year-old woman with chronic nonvalvular atrial fibrillation presented with cardiac arrest during magnetic resonance imaging for back pain evaluation. Brain magnetic resonance imaging performed after cardiopulmonary resuscitation revealed multiple embolic lesions. Transesophageal echocardiography showed a large free floating thrombus ball and multiple mural thrombi in the left atrium. In light of the high-risk situation, an emergency operation was performed despite the occurrence of a fresh stroke within the previous 24 hours. The surgery was successful and the postoperative course was uneventful. The patient has been doing well since the operation on outpatient follow-up for 8 months.     

Constrictive pericarditis with atrial septal defect.

We report on a case of constrictive pericarditis (CP) with atrial septal defect (ASD) in a 50-year-old man. The combination of CP with ASD is rare and occasionally difficult to diagnose. Transthoracic echocardiography demonstrated ASD, but the finding of a thickened pericardium was poor. Diagnosis was confirmed by cardiac catheterization. Pericardiectomy and direct closure of ASD was performed during cardioplegic arrest under the support of cardiopulmonary bypass. The postoperative course was uneventful with marked improvement in symptoms.     

Right atrial myxoma complicated with pulmonary embolism

A 25-year-old woman was admitted to our hospital with chest pain and dyspnea, and was diagnosed as having a right atrial myxoma complicated with pulmonary embolism. An emergency operation was performed with cardiopulmonary bypass. A papillary pedunculated tumor was found having a narrow-based attachment to the free atrial wall. After the tumor was carefully removed together with the atrial wall around the attachment, pulmonary embolectomy was performed. Several fragments of the tumor were removed, and sufficient back-flow from the pulmonary artery was established. The postoperative course was uneventful. However, a non-perfused area was observed in the left lower lung on pulmonary hemodynamic scintigraphy at 3 months after the operation. Long-term observation is required due to the high risk for metastasis and recurrence, and further surgical treatment remains the most appropriate treatment option. A second operation may be needed to prevent progression in complications.     

Concurrent multiple left atrial focal activations with fibrillatory conduction and right atrial focal or reentrant activation as the mechanism in atrial fibrillation

OBJECTIVE: We examined the atrial activation during atrial fibrillation to validate the rationale behind simplified surgical procedures. METHODS: Intraoperative mapping of the entire atrial epicardium was performed in 21 patients with permanent atrial fibrillation and mitral valve disease using a 256-channel, 3-dimensional dynamic mapping system. RESULTS: Concurrent multiple repetitive activations arose from the posterior left atrium adjacent to the pulmonary veins or the left atrial appendage in all patients. The fastest activation propagated toward the right atrium conducting through Bachmann's bundle, leaving the other activations confined to a small atrial region. As the activation propagated toward the right atrium, there was a progressive conduction delay or block in the pathway. As a result, the activation in the right atrium desynchronized with the left atrial activation and became irregular and complex. The average cycle length measured at the right atrial appendage was significantly longer than that at the left atrial foci (206 +/- 32 milliseconds vs 175 +/- 23 milliseconds, P <.001). In addition to the passive activation, a focal activation and reentrant activation were also observed in the right atrium in 5 and 6 patients, respectively. The number of wave fronts in the right atrium was significantly greater than that in the left atrium (2.9 +/- 0.8 vs 0.6 +/- 0.7, P <.001). CONCLUSIONS: Multiple left atrial focal activations with fibrillatory conduction and right atrial focal or reentrant activations are the mechanism in permanent atrial fibrillation associated with mitral valve disease. Intraoperative mapping would facilitate the indication for simplified procedures confined to the left atrium or the pulmonary veins.     

Submitral aneurysm with left atrial communication.

Annular sub-mitral aneurysms are rare lesions of varied etiology. A sub-mitral membranous curtain may be a potential area of weakness through which these lesions expand. Initially described in young males of African origin and reported from varying geographical areas, these lesions arise from the atrioventricular groove in close relation to the mural leaflet. They may cause pressure effects, lead to mitral incompetence and left ventricular dysfunction. Key issues during repair are proximity to the circumflex coronary artery, atrioventricular junction and progressive involvement of the mitral valve. This case report of a calcified bi-lobed sub-mitral aneurysm with communication to the left atrium discusses the anatomical basis of the lesion, the role of computed tomogram angiography in pre-operative evaluation and surgical management.     

Microwave ablation of atrial fibrillation in conjunction with treatment of early postoperative massive left atrial thrombosis

Left atrial thrombosis is a rare complication of both atrial fibrillation and mitral valve surgery. A patient with a massive atrial thrombosis associated with symptoms of severe heart failure is presented. Restoration of rhythmical ventricular contraction and, ultimately, atrial contractility is of great benefit for providing relief from symptoms and for preventing thrombus recurrence. We present an approach to surgically treat atrial fibrillation using a new microwave energy source in a patient with left atrial thrombosis who requires a mitral valve prosthesis replacement.     

Left atrial myxoma with severe inflammatory response

A 59-year-old man was admitted for intermittent fever. His temperature was 38°C, white blood cell counts 19,800/mm³, C-reactive protein 17.9 mg/dL. Interleukin 6 (IL-6) serum level was 31.0 pg/mL. Transesophageal echocardiography showed a 6×4 cm left atrial tumor arising from the atrial septum. We strongly suspected that left atrial myxoma caused the fever. The tumor was excised with the aid of cardiopulmonary bypass. Tumor histology was typical of a cardiac myxoma. The serum IL-6 level decreased rapidly in postoperative two weeks (5.3 pg/mL). In this patient, IL-6 plasma level might be used as a marker of recurrence.     

乙酰胆碱对人房颤心房肌电生理特性的影响

目的 观察房颤时人心房肌细胞动作电位变化及迷走神经递质乙酰胆碱(ACh)对离体人心房肌动作电位(AP)及有效不应期(ERP)的影响.方法 选择20例心脏瓣膜病患者分为两组,其中11例合并房颤者为房额组(AF),9例窦性心律者为对照组(SR),术中取右心耳组织,采用玻璃微电极技术,检测两组患者静息膜电位(RMP),动作电位复极达90％的时程(APD90),动作电位复极达50％的时程(APD50)及不同起搏频率下APD90的变化,同时观察给予Ach前后上述指标的变化.结果 Ach灌注前,AF组与SR组间RMP( 63.70±3.00) mV比(54.70 ±2.19) mV、APD90 (312.60±11.92) ms比(406.30±14.61) ms、APD50( 177.30±14.05) ms比(218.50±15.10) ms差异有统计学意义(P＜0.05).Ach灌注后,AF与SR两组间RMP(67.8±2.0) mV比(61.4±1.8) mV、APD90 (263.60±13.38) ms比(316.20±15.40) ms、APD50( 173.60±16.82) ms 比(217.60±15.16) ms差异有统计学意义(P＜0.05).与灌注前自身比较,两组RMP显著增高、APD90显著缩短(P＜0.05).APD50差异无统计学意义(P＞0.05).但在AF组患者,其APD90缩短程度( △APD90,％)较SR组小(P＜0.05).结论 房颤时存在心房组织APD缩短,频率适应性降低等电重构,它促进了房颤的维持.Ach可加重重构作用,但在慢性房颤中这种作用减弱.这种改变可能是机体对抗房颤的一种调节机制.