Radiofrequency modified maze procedure for chronic atrial fibrillation

Background We studied the effectiveness of Radiofrequency (RF) modified maze in early and late restoration of sinus rhythm in patients with rheumatic heart disease (RHD). Methods We studied 84 patients with RHD over 23.6±12.5 months after the RF modified maze and another group of 64 patients over six months after valvular surgery alone (the Non-Maze group). Any thromboembolic episodes and NYHA class of the patient were recorded. The short term survivors in sinus rhythm, underwent stress test and echocardiography for atrial transport function at 3–6 months after surgery. Results In the Maze group, sinus rhythm was restored in 60/70 patients (85.71%) immediately and sustained in 55/70 patients (78.57%) over the follow-up as against an immediate conversion rate of 5.3% (5/53 patients, p<0.001) in the Non-maze group. The additional Cardiopulmonary (CP) bypass time (p=0.13) and cross clamp time (p=0.511) needed for maze is not statistically significant. Left atrial (LA) transport function was preserved in 41/51 patients (80.4%) and Right atrial (RA) transport function in 51/51 patients (100%). Stress test showed good chronotropic response in all the 41 patients in whom it was performed. In the Maze group one patient presented with acute valve thrombosis and subsequently, succumbed to it. In the non maze group 3/55 patients (5.66%) were hospitalized for stroke. No patient needed permanent pacemaker nor was sinus node dysfunction seen. The immediate postoperative morbidity and mortality was comparable in the two groups. Conclusions The RF modified maze is safe, effective and brief without any additional risk. It restores sinus rhythm in the majority, however there is an attrition in some.     

改良迷宫术治疗心房纤颤的远期疗效

目的：评价改良迷宫术治疗心房纤颤的远期疗效。方法：１９９４年３月到１９９６年７月采用改良迷宫术－－按Ｃｏｘ经典迷宫手术原理用冷冻代替部分手术切割,治疗风湿性心脏膜瓣病合并心房纤颤１８例。同期行二尖瓣替换术１４例,又瓣膜替换术４例,三尖瓣成形术８例,左房血栓清除４例。结果：本组无手术死亡随访２５￣５２个月,平均３６．１个月,随访率１００％。远期死亡１例。生存１７例,心功能Ⅰ级８例,Ⅱ级９例;均持续窦     

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     

Survival and sinus rhythm maintenance after modified Cox/maze procedure and mitral valve operation in patients with chronic atrial fibrillation

OBJECTIVE: Sinus rhythm gained after the Cox/maze procedure concomitant with mitral valve operation has demonstrated long-term attrition during the follow-up, no information exists on whether the type of mitral valve operation--(repair vs. replacement)--affects this sinus rhythm maintenance rate. We retrospectively studied patients undergoing concomitant mitral valve operation and Cox/maze procedure to answer this question. METHODS: Between April 1993 and August 1995, 87 consecutive patients--35 men and 52 women (mean age: 59.3 years)--with chronic atrial fibrillation and mitral valve disease underwent the modified Cox/maze procedure and concomitant mitral valve operation, with 56 having mitral valve repair (repair group) and 31 mitral valve replacement (replacement group). Patients were followed up and changes in rhythm studied retrospectively. RESULTS: Follow-up for a mean 51.3 +/- 11.6 months was completed in 82 of 83 long-term survivors (99%). Repair group surgery survival was 98.1 +/- 1.9% at 1 year and 94.2 +/- 3.2% at 5 based on the Kaplan-Meier method. Replacement group surgery survival was 85.7 +/- 5.9% at 1 year and 82.9 +/- 6.4% at 5. Probability in sinus rhythm maintenance for the repair group at 1 year was 88.6 +/- 5.4% and at 5 years was 67.6 +/- 9.1%. Probability in sinus rhythm maintenance for the replacement group at 1 year was 95.7 +/- 4.3% and at 5 years was 65.0 +/- 11.1%. CONCLUSIONS: Medium-term results after the Cox/maze III procedure concomitant with mitral valve operation are good. The attrition of sinus rhythm maintenance appears similar by the completion of 5-year follow-up.     

Experience with unipolar radiofrequency ablation for atrial fibrillation

BACKGROUND: The cut and sew Cox maze procedure for atrial fibrillation (AF), although effective, is not widely used because of technical complexity, prolonged duration and significant risk of postoperative bleeding. This study reviews our experience with the unipolar radiofrequency ablation (RFA) procedure, which was used to create a modified maze to treat AF. METHODS: A retrospective review of 31 patients undergoing consecutive cardiac surgery who had concomitant RFA for AF over a 16-month period was carried out. A Cobra unipolar RFA probe (EPT; Boston Scientific, San Jose, CA, USA) was used to create a standard set of lesions. RESULTS: There were 20 men and 11 women (mean age, 66 +/- 9 years; range, 48-87 years). AF was continuous in 21 patients and intermittent in 10. The median duration of AF leading up to surgery was 48 months (range, 6 months-20 years). Left atrium was enlarged in 81% of the patients. Operations included mitral valve repair (7 patients), replacement (5), coronary artery bypass (10), aortic valve replacement (1) and combined procedures (8). There were no complications directly attributable to RFA. There were three early deaths. One patient required a permanent pacemaker. Median follow up was 22 months (range, 12-30 months). One patient died 2 years after the operation from a stroke. Cardioversion was attempted in five patients within 3 months of operation and was successful in four. At 2 years following the procedure, the probability of the patient remaining in sinus rhythm was 0.71 +/- 0.15. CONCLUSION: Surgical RFA can be carried out as a useful adjunct to conventional cardiac surgery. Although the results were satisfactory in this series, further studies are needed to refine the indication of the procedure and to assess its longer-term efficacy.     

Left atrial plication combined with mitral valve surgery in patients with a giant left atrium

The benefits of performing left atrial plication during mitral valve surgery for patients with a giant left atrium were evaluated by analyzing the short- and long-term surgical results and changes in the left atrial dimension (LAD) and respiratory function of 30 patients. Of the 30 patients, 2 (7%) died of multiple organ failure on postoperative days 26 and 117, but no other deaths occurred during the mean follow-up of 5.9±2.1 years. Valve thrombosis was observed in one patient and cerebral complications with no residual deficit were observed in two patients, with a 9-year event-free rate of 87±7%. The LAD decreased significantly from 69.0±8.5 mm to 53.7±9.1 mm (P<0.01) shortly after surgery, and this decrease was maintained even 5 years after surgery (53.3±11.4 mm). The cardiothoracic ratio decreased from 74.8±8.3% to 62.8±9.0% (P<0.01) and the vital capacity of the lungs increased from 71.1±18.0% to 82.9±22.2% (P<0.01). Thus, we conclude that performing left atrial plication during mitral valve surgery is safe and effective for patients with a giant left atrium.     

Partial maze procedure is effective treatment for chronic atrial fibrillation associated with valve disease

The maze procedure may be performed in combination with valve operations to treat chronic atrial fibrillation associated with valve dysfunction. Although we initially used the modified Cox maze III procedure, a more limited partial maze procedure is now preferred because the left atrium might be considered as the electrical impetues for atrial fibrillation. In this study we compared the results of 30 patients (group I) who underwent the full biatrial modified Cox maze III and 20 (group II) patients the partial maze procedure. While the rates of restored sinus rhythm were the same in both groups at 6-month follow-up (I: 83.3%, vs II: 80%), the following advantages were noted in the patients undergoing the partial maze procedure: shorter operative times, lesser elevations of creatine phosphokinase, lower rate of blood transfusion, lower rate of junctional rhythm soon after the operation, and a higher P wave in those patients with restored sinus rhythm. The effectiveness of the partial maze procedure seems equal to that of the biatrial modified Cox maze III procedure for atrial fibrillation associated with valve disease. The partial maze procedure is simple and less invasive, and thus might be applied more frequently as an additional procedure to valve operations without additional risk.     

Outcome of the modified maze procedure for atrial fibrillation combined with rheumatic mitral valve disease using cryoablation

This study evaluated the mid-term results of the modified maze procedure using cryoablation for treating atrial fibrillation associated with rheumatic mitral valve disease. Between March 2000 and February 2004, 177 consecutive patients underwent the modified maze procedure using cryoablation concomitant with mitral valve surgery, were divided into the modified Cox-Maze III (group CM, n=88), modified Kosakai-Maze (group KM, n=63) and left atrial maze (group LA, n=26) procedures. Postoperative and follow-up results were analyzed and compared between the groups, with a mean follow-up time of 22.4+/-15.1 months. There were three hospital deaths (1.7%). The operative time was significantly longer in the group CM than the KM or LA groups, respectively. One late death developed in the CM group. At last follow-up, 139 patients had sinus rhythm (79.9%), which was regained in 67 CM (77.9%), 50 KM (80.7%) and 22 (84.6%) LA group (P=0.743) patients. Freedom from stroke at 4 years was 84.6% in the CM, 95.0% in the KM, and 92.9% in the LA (P=0.916) groups. There were no significant differences in the sinus conversion or stroke rate between patients with the left atrial appendage preserved and those with it excised or obliterated. The modified maze procedure using cryoablation is safe and effective, with an acceptable sinus conversion rate and clinical improvement.     

左心房折叠术在二尖瓣病变合并巨大左心房治疗中的应用

目的探讨左心房折叠术治疗二尖瓣病变合并巨大左心房的临床应用效果.方法回顾性分析23例收缩末期左心房内径为(129±37)mm (92～250 mm)、行左心房折叠术的二尖瓣手术患者的临床资料.22例选用人工机械瓣膜置换,1例为生物瓣置换,同期行左心房折叠术.术前心功能NYHA分级,Ⅲ级15例,Ⅳ级8例;术前心胸比为0.79±0.10.单纯二尖瓣置换术18例,其中行三尖瓣成形术10例;双瓣膜置换和三尖瓣成形术5例,其中二次手术2例, 术中行心房纤颤射频消融术2例.结果术后低心排出量综合征3例(13%),呼吸衰竭2例(9%).早期死亡3例(13%),其中2例为低心排出量综合征、1例为脑梗死.术后失访2例,术后1年意外死亡1例,平均随访(44±39)个月,17例生存患者心功能Ⅰ级14例、Ⅱ级3例;术后心胸比为0.68±0.11,较术前明显缩小(t=3.80,P=0.000).结论在瓣膜病手术的同时对巨大左心房症行左心房折叠术,可减少术后并发症,术后效果良好.     

The impact of mitral valve surgery combined with maze procedure

Objective: Recent studies indicated that successful maze procedure for atrial fibrillation (AF) adjunct to mitral valve surgery provided a lower incidence of stroke and recurrence of AF. The purpose of this study is to review the 13-year experience of these combined procedures and to identify the risk factors and late outcomes of successful maze procedures compared to failed maze procedures. Methods: At a single institution, 521 consecutive patients underwent combined maze procedures with mitral valve replacements or valvuloplasties. Three kinds of maze techniques were primarily used: Cox–maze III, Kosakai maze, and cryo-maze procedure. Three months after the operation, 394 patients were in sinus rhythm (Group S) while the remaining 116 patients were in continuous or intermittent AF (Group F), excluding 11 early death patients. Risk factors for Group F were determined by the analysis of all patient demographics. Survival, freedom from stroke, cardiac events, and AF recurrence were analyzed. Results: The proportion of the patients without any other simultaneous procedures was greater in Group S (41% vs 29%, P = 0.02). The distributions of mitral valve surgery and maze procedure techniques were similar in these two groups. A left atrium larger than 70 mm [hazard ratio (HR) = 2.6; 95% confidence interval range 1.04–6.3, P = 0.043], preoperative AF history longer than 10 years (HR = 8.2; 4.5–15.1, P < 0.001) and f-wave voltage in V1 smaller than 0.1 mV (HR = 6.2; 5.0–15.2, P < 0.001) were determined to be risk factors for unsuccessful maze procedures. All the results of Cox proportional hazards models showed superiority in Group S; actuarial survival rates (HR = 2.7; 1.04–7.0, P = 0.035), freedoms from stroke (HR = 3.0; 1.1–8.1, P = 0.003) and cardiac events (HR = 4.3; 2.9–6.1, P < 0.001). Freedom from AF recurrence rate was 98.4% at 5 years and 81.0% at 12 years in Group S, and 73.0% and 60.1% in overall patients. Conclusions: Patients with successful maze procedures resulted in higher survival rate, greater freedom from stroke and cardiac events. The large left atrium, small f-wave, and long AF duration were significant risk factors for failed maze procedures, suggesting that earlier surgical interventions would result in superior results in mitral valve surgery combined with maze procedure.     

Acute left atrial thrombus causing cardiogenic shock following mitral valve replacement: Report of a case

We report herein the rare case of a 53-year-old woman who developed cardiogenic shock due to an acute left atrial thrombus following replacement of the mitral valve. A definitive diagnosis was not able to be made using precordial echocardiography because of the broad, flat shape of the thrombus; however, transesophageal echocardiography imaged the thrombus in detail. The patient was initially stabilized by percutaneous cardiopulmonary support after which a thrombectomy was successfully performed.     

左心房后壁盒式消融的改良心脏迷宫手术疗效

目的 探讨盒式消融术式能否提高心房颤动(房颤)治疗的成功率.方法 2009年1至12月,心脏直视手术同期行改良迷宫手术患者中,行左心房后壁盒式消融术者60例,同期配对选择60例非盒式消融术者作为对照组.两组均经过相对一致的术前检查和围手术期处理.结果 除盒式消融组体外循环时间较长外,两组在年龄、房颤时间、左心房直径、左心室射血分数、同期手术等差异无统计学意义,两组围手术期均无死亡病例.所有病例均顺利随访,平均(9.0±8.4)个月.盒式消融组1例在术后2个月死于脑出血,非盒式消融组1例在术后12个月出现脑梗塞.术后1与3个月,两组免于房颤率分别为70.0％对51.2％(P=0.039)与78.3％对60.0％ (P =0.030);术后6个月分别为80.0％对71.7％ (P =0.286).8例因房颤心律复发再次入院,两组分别有4例和2例行导管消融,两组各有1例行电复律,均恢复窦性心律,并继续口服胺碘酮治疗3个月.结论 盒式消融组通过增加左、右肺静脉之间连线,比非盒式消融组左、右肺静脉之间单一连线,明显提高射频消融迷宫手术后早期(1～3个月)窦性心律的维持率;但在术后半年,两组窦性心律的维持率差异无统计学意义.     

The outcome and indications of the Cox maze III procedure for chronic atrial fibrillation with mitral valve disease

Objective: The efficacy of the Cox maze III procedure for chronic atrial fibrillation associated with mitral valve disease is unclear, and so was evaluated in this study. Methods: In 30 patients, we applied the maze III procedure (cut and suture), except for one modification in the case of a left posterior sinus node artery. After dividing the patients into sinus rhythm and atrial fibrillation groups more than 6 months after the operation, we compared various parameters. Results: Sinus rhythm was restored in 27 patients (90%). One patient had atrioventricular reentrant tachycardia and needed a pacemaker for sick sinus syndrome (3.3%). The f-wave voltage in lead V₁, the preoperative cardiothoracic ratio, the preoperative left atrial systolic dimension, and the duration of atrial fibrillation were 0.23 ± 0.10 mV, 60.4% ± 5.2%, 57.4 ± 8.2 mm, respectively, and 5.1 ± 4.6 years in the group with sinus rhythm, and were 0.06 ± 0.05 mV, 77.7% ± 10.3%, 95.3 ± 24.0 mm, respectively, and 11.8 ± 5.5 years in the group with atrial fibrillation. These parameters were all significantly different between the groups. Regarding atrial function, a transmitral flow A wave was detected in 66.7% and a transtricuspid flow A wave in 100%. Only the duration of atrial fibrillation had a significant influence on the restoration of left atrial function. Conclusion: The maze III procedure was effective for atrial fibrillation associated with mitral valve disease. This procedure should be applied to patients with a cardiothoracic ratio less than 70% and a left atrial systolic dimension less than 80 mm. (J Thorac Cardiovasc Surg 1998;116:220-7)     

Biatrial maze procedure versus pulmonary vein isolation for atrial fibrillation during mitral valve surgery: New analytical approaches and end points

Objective

To use novel statistical methods for analyzing the effect of lesion set on (long-standing) persistent atrial fibrillation (AF) in the Cardiothoracic Surgical Trials Network trial of surgical ablation during mitral valve surgery (MVS).