Simple Left Atrial Procedure for Chronic Atrial Fibrillation Associated With Mitral Valve Disease

Background. A computerized 48-channel mapping system was used to investigate the characteristics of an atrial epicardial electrogram during chronic atrial fibrillation (AF) in patients with solitary mitral valve disease. We have devised a simple left atrial procedure to eliminate the chronic AF during a mitral valve operation.

Methods. Using this mapping system, we performed intraoperative atrial mapping in 11 patients with chronic AF associated with mitral valve disease. The AF duration ranged from 0.4 to 15 years (mean, 8.0 ± 4.5 years). A simple surgical ablation of the AF on the left atrium only was performed during the mitral valve operation.

Results. The mean AF cycle length of the atria ranged from 129 to 169 milliseconds in the right atrium and from 114 to 139 milliseconds in the left atrium. The mean AF cycle length of the left atrium was shorter than that of the right atrium. Regular and repetitive activation was found in the left atria of 7 of 11 patients. The AF disappeared in all patients immediately after the operation, and 10 of these patients continued to have a sinus rhythm postoperatively (AF-free rate, 91%).

Conclusions. Computerized intraoperative mapping revealed a shorter mean AF cycle length in the left atrium. A simple left atrial procedure was effective in eliminating chronic AF associated with solitary mitral valve disease.     

A modified maze procedure performed only on the left atrium for chronic atrial fibrillation associated with mitral valve disease: Report of a case

We describe herein the successful treatment of a patient with chronic atrial fibrillation (AF) associated with mitral valve stenosis and regurgitation, achieved by performing a modified maze procedure on the left atrium alone. The patient was a 51-year-old man who had suffered from intractable AF for 17 years, causing multiple cerebral emboli and palpitations. He had undergone open mitral commissurotomy and balloon commissurotomy 15 and 7 years ago, respectively. On admission, an echocardiogram revealed mitral valve restenosis and thrombosis in the left atrial appendage. Prosthetic valvular replacement was performed following isolation of all pulmonary veins with cryoablation to the posterior wall of the left atrium and excision of the left atrial appendage. Postoperatively, the AF disappeared and echocardiogram demonstrated a left atrial kick in the mitral valvular inflow without any evidence of thrombosis in the left atrium. Thus, we believe that our modified left side only maze procedure is a simple and efficient method for the treatment of chronic AF with mitral valve disease.     

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.     

Left atrial isolation associated with mitral valve operations.

Surgical isolation of the left atrium was performed for the treatment of chronic atrial fibrillation secondary to valvular disease in 100 patients who underwent mitral valve operations. From May 1989 to September 1991, 62 patients underwent mitral valve operations (group I); 19, mitral valve operations and DeVega tricuspid annuloplasty (group II); 15, mitral and aortic operations (group III); and 4, mitral and aortic operations and DeVega tricuspid annuloplasty (group IV). Left atrial isolation was performed, prolonging the usual left paraseptal atriotomy toward the left fibrous trigone anteriorly and the posteromedial commissure posteriorly. The incision was conducted a few millimeters apart from the mitral valve annulus, and cryolesions were placed at the edges to ensure complete electrophysiological isolation of the left atrium. Operative mortality accounted for 3 patients (3%). In 79 patients (81.4%) sinus rhythm recovered and persisted until discharge from the hospital. No differences were found between the groups (group I, 80.7%; group II, 68.5%; group III, 86.7%; group IV, 75%; p = not significant). Three late deaths (3.1%) were registered. Long-term results show persistence of sinus rhythm in 71% of group I, 61.2% of group II, 85.8% of group III, and 100% of group IV. The unique risk factor for late recurrence of atrial fibrillation was found to be preoperative atrial fibrillation longer than 6 months. Due to the satisfactory success rate in recovering sinus rhythm, we suggest performing left atrial isolation in patients with chronic atrial fibrillation undergoing valvular operations.     

Free floating ball thrombus of left atrium developing late after closed mitral commissurotomy - a case report

Left atrial ball thrombus is very rare entity and it is even rare to find a large free floating ball thrombus of left atrium in a post-operative patient. Thrombus of left atrium usually occurs in atrial fibrillation or in mitral valve stenosis. Here we are presenting a case of large ball thrombus of left atrium in a patient who underwent closed mitral commissurotomy 21 years back. A 50 years old female patient was admitted with history of breathlessness, palpitation and cough of one month duration. She was doing well after mitral valve commissurotomy. Her pre-operative trans-thoracic echocardiography showed a left atrial thrombus and severe mitral stenosis with valvular area of 0.7 cm² and atrial fibrillation. Per-operative trans-oesophageal echocardiography showed a large free floating ball thrombus of left atrium. She underwent removal of left atrial thrombus and mitral valve replacement using Sorin Bicarbon valve.     

Cor triatriatum in adulthood with mitral valve regurgitation and atrial fibrillation

Cor triatriatum is a rare congenital heart disease. A 57‐year‐old woman had cor triatriatum with severe mitral valve regurgitation (MR) and atrial fibrillation (AF). We performed mitral valve repair, left atrial appendage resection, and maze procedure by resection of the anomalous septum in the left atrium. As a result, MR was controllable and AF disappeared after the operation. Although there is no established maze procedure with cor triatriatum, removing the septum was effective to complete it.     

心房纤维颤动的外科治疗

３例采用改良迷宫术探索进行心房纤颤外科治疗获成功。病人术前均为风湿性心脏病，心功能Ⅲ－Ⅳ级，心房纤颤病史３－１０年，左房直径５２－５８ｍｍ，心胸比率０．６４－０．７０。在进行改良迷宫术的同时，２例行二尖瓣替换，１例行双瓣替换及三尖瓣环缩。术后２例自动复跳，１例电击除颤复跳。３例术后早期均为窦性心律。２例术后３年恢复良好，正常心律，心功能Ｉ级；１例术后３个月死于脑血管意外。文中重点介绍了手术方法，提     

Free-floating left atrial ball thrombus without mitral valve disease

Reports of left atrial ball thrombus without mitral valve disease are few. We experienced a case of free-floating left atrial ball thrombus that developed in a short period in a patient with atrial fibrillation and dilated left atrium but intact mitral valve. Surgical removal of the thrombus was performed. It was presumed that atrial fibrillation and enlarged left atrium were the contributory factors to thrombus development.     

不同类型二尖瓣病变者左房心肌组织氧化应激特点及其与心房颤动的关系

目的 探讨不同类型二尖瓣病变心房肌氧化应激特点及其与心房颤动(AF)的关系.方法 24例二尖瓣病变者,其中二尖瓣狭窄(MS)和二尖瓣关闭不全(MR)各12例(窦性心律各6例,AF各6例).术中切取部分左心耳组织,4例意外死亡者作为对照.免疫组织化学染色评价3-硝基酪氨酸(3-nitrotyrosine,3-NT)表达.比色法检测心肌肌酸激酶(creatine kinase,CK)、肌型肌酸激酶同工酶(MM isoenzyme of creatine kinase,CK-MM)、肌球蛋白ATP酶活性.Western blotting评价心肌CK-MM含量及CK-MM中3-NT的表达.结果 所有病人心房肌3-NT表达均明显增高(P＜0.05),AF者表达高于窦性心律者(P＜0.05),MS者表达高于MR者(P＜0.05).病人心肌CK、CK-MM活力均降低(P＜0.05),CK活力与心房肌3-NT表达呈负相关(r=-0.382,P＜0.05),CK-MM活力与其3-NT表达亦成负相关(r=-0.446,P＜0.05).结论 二尖瓣病变者心房肌氧化应激反应明显升高,MS者心房肌氧化应激反应高于MR者.心房肌氧化应激与AF的持续存在有关.CK和CK-NN中酪氨酸硝基化可以降低其活力.     

Electrocautery maze in chronic atrial fibrillation: An early experience

Introduction The maze procedure is the only surgical treatment that can alleviate the three physiologic sequelae of atrial fibrillation i.e. tachycardia, thromboembolic events and hemodynamic compromise. In the present study, we attempted ablation of atrial fibrillation (AF) using monopolar conventional cautery. Objective is to demonstrate efficacy of electroxcautery maze in chronic AF in patients undergoing mitral valve surgery and long term efficacy of it in maintaining sinus rhythm. Methods In this series 25 patients who underwent electrocautery maze since 2002 were studied, the age ranged from 20–60 years, 60% of patients were females. 20 patients were in NYHA class IV and 5 patients were in class III, who had left atrium (LA) ranging from 5–6.5 cms with LA appendage clot in 8 patients. All patients underwent mitral valve replacement, 3 patients under went tricuspid valve repair and 2 underwent aortic valve replacement as concomitant procedures. The electrocautery maze was done encircling left & right pulmonary veins along with interconnecting portion. Left atrial appendage was ligated only in cases with LA clot. Results The hospital mortality rate was nil in this group of patients. Freedom from atrial fibrillation or atrial flutter was 92% at 6mths followup. Patients were followed up with regular electrocardiography. Conclusion Electrocautery maze procedure, an adjunctive procedure is safe, time sparing & effective in eliminating atrial fibrillation & restoring atrial transport function. Presented at the 50^th Annual Meeting of IACTS, New Delhi, Feb., 2004.     

Free-floating left atrial ball thrombus without mitral valve disease

Reports of left atrial ball thrombus without mitral valve disease are few. We experienced a case of free-floating left atrial ball thrombus that developed in a short period in a patient with atrial fibrillation and dilated left atrium but intact mitral valve. Surgical removal of the thrombus was performed. It was presumed that atrial fibrillation and enlarged left atrium were the contributory factors to thrombus development. (Jpn J Thorac Cardiovasc Surg 2005;53:52–54)     

Efficacy of pulmonary vein isolation for the elimination of chronic atrial fibrillation in cardiac valvular surgery

BACKGROUND: Haissaguerre and colleagues emphasize the importance of the pulmonary veins as a source of ectopic foci for initiating paroxysmal atrial fibrillation (AF). We hypothesized that ectopic foci from the pulmonary veins could also act as drivers for maintaining chronic AF, and that surgical ablation of the pulmonary vein orifices could terminate chronic AF. METHODS: Using a computerized 48-channel mapping system, we performed intraoperative atrial mapping in 12 patients with chronic AF associated with mitral valve disease. Patient age ranged from 24 to 82 years (mean, 60.4 years). AF duration ranged from 3 to 240 months (mean, 92+/-84 months). Simple surgical isolation of the pulmonary vein orifices was performed during the mitral valve operation. RESULTS: Regular and repetitive activation was found in the left atria of 9 out of 12 patients, and irregular and chaotic activation was found in both atria of 3 out of 12 patients. Chronic AF in the 9 patients (75%) with regular and repetitive activation of their left atria was successfully treated by a simple surgical isolation of the pulmonary vein orifices. The other 3 patients did not recover sinus rhythm after this procedure. In 1 case of recurrent AF, the patient recovered sinus rhythm during the follow-up period (AF-free rate, 83%). CONCLUSIONS: Surgical ablation of the pulmonary vein orifices was effective in the treatment of chronic AF associated with mitral valve disease. Intraoperative mapping may be useful in predicting the efficacy of a single pulmonary vein orifice isolation procedure.     

慢性心房颤动合并二尖瓣病的迷宫手术

作者自１９９５年至１９９６年１０月共作２０例慢性心房颤动的迷宫手术和二尖瓣替换或修复术。术吣外膜标测结果左房多为扑（１４／２０）,右房则往往是颤动（１８／２０）。无早期死亡。２０例随访３个月以上,其中１４例随访在１年以上,经电生理检查均为窦性心率,房室同步活动,不能诱发房颤;经多普勒超声心动图检查,左和右心房输出功能正常。晚期死亡１例,手术后４年半月死于急性坏死性肝炎,对迷宫手术作了一些改进,术后     

二尖瓣置换同期全迷宫射频消融术后患者心房功能与心房纤维化的关系

目的观察二尖瓣置换同期全迷宫射频消融术后患者心房功能的恢复情况,并探讨其与心房纤维化的关系。方法采用队列研究方法分析2010年1～8月期间沈阳军区总医院收治以二尖瓣病变为主的心瓣膜病合并慢性心房颤动（房颤）32例患者的临床资料,其中男11例、女21例,年龄（49.8±8.7）岁;其中单纯风湿性二尖瓣狭窄14例,风湿性二尖瓣狭窄伴关闭不全8例,二尖瓣脱垂10例;术前房颤持续时间（3.6±4.6）年。所有患者均行二尖瓣置换加全迷宫射频消融术。以左心耳纤维化程度的中位数10.9%为割点,将32例患者按心房纤维化的程度不同分为纤维化较重患者（纤维化程度〉10.9%）19例,纤维化较轻患者（纤维化程度〈10.9%）13例。采用免疫组织化学法检测心肌纤维化程度,用超声心动图检测左心房结构和功能的改变。结果无围术期死亡。体外循环时间（84.6±22.6）min,主动脉阻断时间（47.6±15.6）min;监护室停留时间（3.2±1.5）d。32例患者均随访半年以上,随访时间（1.3±0.6）年。32例患者的心房壁纤维化程度为4.8%～18.3%（10.7%±4.2%）,19例纤维化较重患者术前和术后3个月左心房内径（LAD）、左心房面积变化分数（LAFAC）及瓣环运动与13例纤维化较轻患者差异无统计学意义（P〉0.05）;心房纤维化较轻患者术后6个月LAD明显缩小（P〈0.05）;二尖瓣侧壁瓣环处的舒张晚期运动峰速（Am）显著提高（P〈0.05）;LAFAC有一定改善（P=0.067）。32例患者中二尖瓣置换术加射频消融术后3个月时有28例患者（87.5%）恢复为窦性心律,21例可维持窦性心律6个月以上（65.6%）,左心房后壁纤维化程度较轻的患者容易维持窦性心律（P=0.010）。结论二尖瓣手术同期行全迷宫射频消融术后6个月心房功能得到改善,与心房纤维化程度有一定的关系。     

Simple surgical isolation of pulmonary veins for treating secondary atrial fibrillation in mitral valve disease

BACKGROUND: Chronic atrial fibrillation (AF) due to mitral valve disease has been successfully treated by surgery. We performed a study to evaluate the effectiveness of a surgical method of simple pulmonary vein isolation (PVI) without radiofrequency or cryoablation in the restoration of sinus rhythm in a group of patients. METHODS: Fifteen patients were operated on for mitral valve disease and chronic AF. The technique consists basically of a circumferential incision excluding the pulmonary vein ostia from the left atrium. RESULTS: Sinus rhythm was achieved in 92.3% of the patients at 6-month follow-up. Echocardiograms 2 months after surgery showed a mean decrease of 1.1 cm in left atrial size. Effective atrial ejection was reestablished in all patients in whom sinus rhythm was achieved (mean LA ejection fraction 41% +/- 14%). Twenty-four hour Holter recordings did not show episodes of paroxysmal atrial fibrillation in any patients. Four patients had isolated episodes of ventricular ectopic beats. Stress electrocardiograms showed mean maximal ventricular response was 64% +/- 11% and 73% +/- 9% of predicted value at 2 and 6 months, respectively. All patients had improved NYHA functional class after surgery; 74% of patients were in NYHA functional class I at 6 months compared with 13.3% preoperatively. CONCLUSIONS: Pulmonary vein isolation without the use of radiofrequency or cryoablation is effective in restoring sinus rhythm in patients with chronic AF secondary to mitral valve disease. Based on simple surgical incisions, this technique is more advantageous than others requiring additional instrumentation.     

Left atrial reduction and mitral valve surgery: the "functional-anatomic unit" concept

The desired outcome for patients undergoing mitral valve surgery includes both good function of the mitral valve, and preservation and restoration of sinus rhythm. To achieve such an outcome, we evolved the concept of the left atrium and mitral valve as a "functional anatomic unit." In this report, we describe a technique for reduction in left atrial size, isolation of the pulmonary veins, and amputation of the left atrial appendage in combination with mitral valve repair. We performed such a procedure in 4 patients, with rheumatic mitral valve disease and chronic atrial fibrillation, with restoration of good valve function and sinus rhythm at 16 to 20 months after surgery.     

Validation of a left atrial lesion pattern for intraoperative ablation of atrial fibrillation

BACKGROUND: Evidence that atrial fibrillation may begin in early stages from triggers or reentry circuits primarily in the left atrium suggests that the entire Maze 3 lesion pattern may be unnecessary. In the present study we describe a new left atrial lesion pattern for intraoperative linear ablation of chronic atrial fibrillation. METHODS: Endocardial radiofrequency ablation was performed on 12 dogs with chronic atrial fibrillation. Lesions to isolate pulmonary veins in pairs, the left atrial appendage, and connecting lesions between these structures were administered in a randomized approach. RESULTS: Twelve dogs were in chronic atrial fibrillation for 31 +/- 21 days before ablation. Atrial fibrillation was successfully ablated and rendered noninducible in all 12 dogs. All treatment failures observed with less than the full lesion pattern became a success when the remaining lesions were given. CONCLUSIONS: Atrial fibrillation ablation using this left atrial lesion pattern is highly successful in this model. This approach may have significant utility as a concomitant procedure for patients with atrial fibrillation undergoing mitral valve procedures.     

Clinical analysis of results of a simple left atrial procedure for chronic atrial fibrillation

BACKGROUND: We have performed a simple left atrial procedure for eliminating chronic atrial fibrillation (AF) associated with mitral valve disease. This article analyzes the midterm results of this procedure. METHODS: Thirty-two patients were enrolled in this study concomitant with mitral valve operations. Patients were divided into two groups (AF- and AF+). We examined the efficacy of this operation and atrial function for more than 12 months of follow-up. RESULTS: In a total of 98.5 patient years of follow-up, AF was absent 3 years after operation in 74%. Of preoperative and intraoperative variables, only long duration o     

Radiofrequency ablation of atrial fibrillation during mitral valve surgery

Twenty-three patients underwent endocardial radiofrequency ablation of atrial fibrillation (AF) during mitral valve procedures with a previously described left atrial lesion pattern. A temperature-controlled 7-coil surgical probe delivered 60-second lesions at 80 degrees C. The left atrial appendage was oversewn after ablation. Ages ranged from 28 to 88 years. Nineteen patients had chronic AF that was present for over 1 year in 74%; 12 patients had rheumatic mitral stenosis. Mean left atrial diameter was 5.4 +/- 0.7 cm. There was 1 operative death unrelated to the ablation, and no strokes or ablation-related complications were observed. At mean follow-up of 32.5 weeks, 86% of the 22 survivors were in sinus rhythm. All 18 patients with left atrial diameter <6 cm are in sinus rhythm. All postoperative atrial flutter was transient, and no patients required subsequent transcatheter ablation. This lesion pattern is safe and effective when applied in the method described here. It appears to be a reasonable alternative to the complete Maze 3 lesion pattern in patients with mitral valve disease.     

Atrial compartment operation for atrial fibrillation: to isolate the left atrium or not?

BACKGROUND: The atrial compartment operation was designed to convert atrial fibrillation (AF) to sinus rhythm with intentional preservation of the electrical connection between adjacent atrial compartments. However, incidental left atrial isolation was observed in some patients. This study compared the long-term clinical outcomes of left atrial isolation for AF with those with right and left atrial connection. METHODS: Twenty patients with mitral valve disease and chronic AF who underwent atrial compartment operation with successful sinus conversion were studied. Left atrial isolation was documented by local electrogram recording. When there were no signs of electrical connection between the left atrium and the rest of the heart, either during sinus rhythm or during stimulation from various atrial compartments, left atrial isolation was confirmed. All patients were followed by electrocardiogram and echocardiogram serial recordings. Clinical signs and symptoms of cardiac performance and thromboembolism were also examined. RESULTS: Seven patients showed an isolated left atrium and 13 patients had electrical connection between the right and left atria. The age, gender, AF duration, and underlying disease were not different between the two groups of patients. During a mean follow-up period of 66 +/- 15 months, none of the patients with left atrial isolation showed recurrence of AF, although one experienced paroxysmal atrial flutter. However, 8 of the 13 patients with right and left atrial connection experienced recurrent atrial flutter/fibrillation (6 atrial flutter and 5 AF) (p = 0.058). The propensity for recurrent atrial flutter/fibrillation in these patients may be related to the conduction delay between the two atrial compartments, measured at 142 +/- 48 ms. At the end of the follow-up period, all patients with left atrial isolation remained in normal sinus rhythm without antiarrhythmic drugs. Of the patients who had right and left atrial connection, 2 developed sustained AF and 1 developed atrial flutter. Patients with left atrial isolation showed a decreased transmitral "A" flow compared with those with right and left atrial connection. Postoperative left atrial diameter and clinical functional class did not differ between patients with and without left atrial isolation. The incidence of embolization observed in both treatment groups did not differ significantly: 14% (1/7) in patients with left atrial isolation and 8% (1/13) in patients with right and left atrial connection (p > 0.05 between the groups). CONCLUSIONS: Left atrial isolation confers a better arrhythmia outcome but at the expense of poorer mechanical performance as compared with preserved electrical connection between the two atria. Nonetheless, all patients remain at risk for systemic embolization. Therefore, modifications of current surgical incisions for AF are needed.