Intra-operative cooled-tip radiofrequency linear atrial ablation to treat permanent atrial fibrillation.

AIMS: To demonstrate the safety and efficacy of saline irrigated cooled-tip atrial linear endocardial radiofrequency ablation (SICTRA) concomitant to open-heart surgical procedures in the treatment of permanent atrial fibrillation (AF). METHODS AND RESULTS: Two hundred and twenty-two patients presenting with permanent AF and the need for cardiac surgery were included. In addition to the cardio-surgical procedure [mitral valve (MV) surgery (n = 94), aortic valve replacement (n = 29), bypass surgery (n = 76 including 24 patients with additional MV surgery), and combined procedures (n = 23)] concomitant SICTRA was performed. In 116 patients, the ablation pattern was restricted to the left atrium alone. During the mean follow-up of 29 months, 174 patients (78%) converted to sinusrhythm (SR). In patients with SICTRA restricted to the left atrium conversion rates were not different compared to a biatrial approach (83 vs. 74%, P = 0.47). Thirty-days mortality was found to be 4% (9/222). Post-mortem evaluation revealed 23% of all lesions to be histologically non-transmural. In the overall group, only 4% of patients developed sustained secondary regular atrial arrhythmia. CONCLUSIONS: SICTRA safely and effectively restores stable SR in 78% of patients with permanent AF undergoing open-heart surgery. Rhythm outcome is not influenced by treatment of the right atrium. Sustained regular atrial arrhythmia with the need for invasive treatment strategies occurs in 4% although intra-operative ablation lesions are often non-transmural.     

Left atrial radiofrequency compartmentalization for chronic atrial fibrillation during heart surgery

BACKGROUND: The excellent results of the Maze III operation have demonstrated that a surgical cure of atrial fibrillation (AF) is possible. A simplified Maze procedure with radiofrequency (RF)ablation of the atrial tissue added to open heart surgery may help to cure chronic AF with low risk. METHODS: From May 1998 to March 2001, an RF left atrial compartmentalization concomitant to a cardiac surgical intervention was performed on 40 of 1,258 patients (3.2 %). Thirty-seven patients had mitral valve disease, two had aortic valve disease and one had coronary artery disease. All patients presented with chronic refractory AF for a mean time of 40.4 months ranging from 4 months to 18 years. RESULTS: Mitral valve replacement (MVR) was performed in 19 patients, mitral valve repair in 12, combined aortic and mitral valve procedures were performed in 6, aortic valve replacement(AVR) in 2 and CABG in 1 patient. Cardiopulmonary bypass time for the complete procedure was 138 +/- 32 minutes with an ablation time of 19 +/- 5 minutes. No complication related to RF application was noted. Sinus rhythm was present in 68% after 12.5 +/- 8.5 months. CONCLUSIONS: RF left atrial compartmentalization combined with cardiac surgical interventions proved to be easy and safe to perform. The long-term results still have to be confirmed with further regular patient follow-up examinations.     

Efficacy of intra-operative radiofrequency ablation in patients with permanent atrial fibrillation undergoing concomitant mitral valve replacement

BACKGROUND: Permanent atrial fibrillation (AF) is present before operation and persists after surgery in 30-40% of patients undergoing mitral valve surgery. Using the maze procedure, 75-82% of patients can be cured of AF, but the procedure is difficult and long lasting. Percutaneous radiofrequency (RF) ablation has emerged as an effective therapy for AF in recent years. AIM: To assess the efficacy of intra-operative RF ablation of AF in patients undergoing mitral valve surgery. METHODS: 100 adults with permanent AF underwent mitral valve replacement. Patients were divided into two groups: the RF group--50 patients qualified for mitral valve replacement and RF ablation; and the control group--50 patients selected for mitral valve replacement without ablation. Odds ratio and 95% confidence interval were examined to assess the influence of several factors on the outcome (free from AF during one-year follow-up based on symptoms and serial Holter ECG recordings). RESULTS: Baseline clinical, demographic and echocardiographic characteristics were similar in both groups. Electrical cardioversion following surgery was required in 76% of patients from the RF group compared with 94% from the control group (p<0.002). In those who underwent cardioversion, sinus rhythm was restored more frequently in RF than control patients (32 vs. 16%, p<0.002). Sinus rhythm at hospital discharge was present in 56% of RF patients compared with 22% of controls (p=0.0001), and after one-year follow-up in 54 vs. 16% (p<0.001), respectively. The use of amiodarone was significantly lower in RF patients compared with controls (32 vs. 70%, p<0.05). NYHA class III (OR 8.5, CI 1.0-394) or IV (OR 36, CI 1.2-1958) and left atrial diameter >6 cm (OR 9.3, CI 0.5-5230) were identified as predictors of AF. CONCLUSIONS: Intra-operative RF ablation performed in the left atrium in patients with chronic AF undergoing mitral valve replacement significantly improves sinus rhythm restoration rate. Advanced heart failure (NYHA class IV) and left atrial diameter >6 cm are negative prognostic factors for sinus rhythm maintenance.     

Efficacy of an additional MAZE procedure using cooled-tip radiofrequency ablation in patients with chronic atrial fibrillation and mitral valve disease. A randomized, prospective trial.

AIMS: This study is the first prospective randomized trial evaluating the efficacy of an antiarrhythmic surgical procedure in patients with chronic atrial fibrillation undergoing mitral valve replacement. METHODS AND RESULTS: Thirty consecutive patients with chronic atrial fibrillation undergoing mitral valve replacement were randomized for an additional modified MAZE-operation using intra-operatively cooled-tip radiofrequency ablation (group A) or mitral valve replacement alone (group B). Biatrial contraction was studied and functional capacity was evaluated in spiro-ergometry 6 months after surgery. Thirty-day mortality was 0% in both groups. After 12 months, sinus rhythm was reinstituted significantly more often in patients of group A (cumulative rate of sinus rhythm 0.800) compared to patients in group B (0.267) (P<0.01). 66.7% of patients in sinus rhythm of group A had documented biatrial contraction. Electrocardioversion showed long-term success in only 17% of patients in group A and 0% in group B. Maximal aerobic uptake at the 6-month spiro-ergometry revealed no significant difference (9.3 vs 8.5 ml x min(-1) kg(-1), P=0.530). CONCLUSIONS: A modified MAZE operation using cooled-tip radiofrequency ablation can be safely combined with mitral valve surgery and is highly effective in restoring sinus rhythm. Biatrial contraction is found in 66.7% of patients with sinus rhythm undergoing mitral valve replacement plus the MAZE operation.     

Superior left atrial approach to the mitral valve: incidence of postoperative arrhythmia

BACKGROUND AND AIM OF THE STUDY: The superior left atrial approach to mitral surgery involves exposure of the mitral valve through a longitudinal, craniocaudally orientated incision in the roof of the left atrium. The study aim was to evaluate the incidence of postoperative arrhythmias following this procedure. METHODS: Fifty-nine patients underwent either mitral valve repair (n = 20), mitral valve replacement (n = 26) or an associated procedure (n = 13), including aortic valve replacement, coronary artery bypass grafting and atrial septal defect closure. Eight patients had undergone previous surgery on the mitral valve. Patients were classified according to their preoperative rhythm: sinus rhythm (SR), paroxysmal or chronic atrial fibrillation (AF), or permanent pacing. Changes in cardiac rhythm were evaluated postoperatively, after four weeks, and at late follow up (mean 23.8 months). RESULTS: Preoperatively, 24 patients had shown SR, 10 had paroxysmal AF, 24 had chronic AF, and one patient had permanent pacing. At the time of discharge, SR was recorded in 18 patients who had SR preoperatively, in seven who had paroxysmal AF preoperatively, and in one patient who had chronic AF preoperatively. At follow up, SR was seen in 19 patients with preoperative SR, in seven with paroxysmal AF preoperatively, and in two with chronic AF preoperatively. Four patients received permanent pacemakers postoperatively due to total heart block or bradycardia. CONCLUSION: The superior left atrial approach to mitral valve surgery appears to be safe as it maintains the sinus rhythm in a high proportion of patients postoperatively. In addition, it is not normally prone to technical complications.     

Features of patients with severe mitral stenosis with respect to atrial rhythm. Atrial fibrillation in predominant and tight mitral stenosis.

The aim of this study was to assess the features of patients with severe mitral stenosis in relation to atrial rhythm. Six hundred and fifty patients (pts) with severe mitral stenosis (MS) (valve area less than or equal to 1.5 cm2) who underwent percutaneous balloon commissurotomy (n = 600) or surgery (n = 50) were classified into 3 groups according to their atrial rhythm (AR): group A: sinus rhythm (SR) (n = 379), group B: SR with episodes of transient atrial fibrillation (AF) (n = 65), group C: permanent AF (n = 206). Uni- and multivariate analysis of clinical, echocardiographic and hemodynamic parameters with respect to the atrial rhythm was performed. Some parameters were comparable in all 3 groups: sex, pulmonary, right and left atrial pressures, mitral valve area, incidence of associated aortic valve disease. Nine parameters were different: mean age, NYHA class III or IV, previous commissurotomy, previous embolism, cardiac index, mitral regurgitation, tricuspid regurgitation, left atrium diameter, mitral calcification. Multivariate analysis, identified age, left atrial diameter and presence of mitral calcification as independent predictors of atrial fibrillation. Transoesophageal echocardiography was performed in 167 cases. A spontaneous echo contrast was recorded in 106 cases (63.5%) and was significantly correlated with a history of embolism and or left atrial thrombi detected by echocardiography. Atrial fibrillation, size of left atrium, severity of mitral stenosis and cardiac index were found to be independent predictive factors of spontaneous echo contrast.     

Clinical determinants of sinus conversion by radiofrequency maze procedure for persistent atrial fibrillation in patients undergoing concomitant mitral valvular surgery

The radiofrequency Maze procedure can effectively restore sinus rhythm in most patients with atrial fibrillation (AF) and mitral valve disease. AF after cardiac surgery is associated with increased morbidity and mortality. However, clinical determinants of long-term postoperative AF after the radiofrequency Maze procedure and concomitant mitral valve surgery are poorly defined. This study comprised 99 consecutive patients with persistent AF and mitral valve disease who underwent radiofrequency Maze procedures and concomitant mitral valvular operations. The predictive values of clinical variables for postoperative AF were examined. After a mean follow-up period of 46.1+/-24.6 months, 83 patients (83.8%) had sinus conversion after the Maze procedure, and 16 patients remained in persistent or paroxysmal AF. Multiple logistic regression analysis determined that predictors of sinus conversion were preoperative left atrial diameter (odds ratio [OR] 1.127 per 1-mm increment in left atrial diameter, 95% confidence interval [CI] 1.045 to 1.215, p<0.002) and the duration of AF (OR 1.022 per 1-month increment in duration of AF, 95% CI 1.009 to 1.035, p<0.001). Discriminant analysis showed that the sinus conversion rate was significantly lower in patients with preoperative left atrial diameters>56.8 mm (p<0.001) or AF duration>66 months (p<0.001) than in patients with preoperative left atrial diameters<56.8 mm or AF duration<66 months. In conclusion, the preoperative left atrial size and duration of AF are primary predictors of sinus conversion by the radiofrequency Maze procedure for patients with persistent AF and mitral valve disease.     

Favorable effect of balloon mitral valvuloplasty on the incidence of atrial fibrillation in patients with severe mitral stenosis.

BACKGROUND: The long-term effect of balloon mitral valvuloplasty (BMV) on the incidence of atrial fibrillation (AF) in patients with severe mitral stenosis (MS) remains undetermined. AIMS: To assess the effect of successful BMV on the incidence of chronic AF in patients with severe MS, compare the results with historical controls, and identify factors associated with AF in such patients. METHODS: Retrospective analysis of 382 consecutive patients with severe MS and in sinus rhythm (SR) who underwent successful BMV (post procedure mitral valve area (MVA) > or =1.5 cm(2), mitral regurgitation (MR) < or =2/4) at our hospital and followed-up for 1-15.6 (mean 5.6 +/- 3.9) years with clinical and echocardiographic examination. RESULTS: Thirty-four (8.9%) patients developed AF at follow-up (group A) and 348 patients (group B) remained in SR. At baseline, and in comparison with group B, patients who developed AF (group A) were older, had higher mitral echo score but equal MVA and left atrial (LA) size. The postprocedure MVA was smaller in group A (1.7 +/- 0.3 cm(2)) than in group B (2.0 +/- 0.2 cm(2;) P = 0.002). At follow-up, and in comparison to group B, group A had smaller MVA (1.5 +/- 0.4 cm(2) vs 1.8 +/- 0.4 cm(2) P <0.0001), larger LA dimension (49.4 +/- 6.5 vs 42 +/- 6.5 mm; P <0.0001) and higher restenosis rate (35% vs 14%; P = 0.001). Multivariate logistic regression analysis identified age at follow-up (P < 0.0001), LA size at follow-up (P = 0.004), and MVA at follow-up (P = 0.006) as predictors of AF. CONCLUSIONS: This study demonstrated favorable effect of BMV on the incidence of AF (8.9%) in patients with severe MS in comparison with reported series (29%) of patients with severe MS with similar baseline characteristics who were not submitted to any intervention. The predictors of AF were age, larger LA, and smaller MVA, at follow-up.     

Factors related to sinus rhythm at discharge after radiofrequency ablation of permanent atrial fibrillation in patients undergoing mitral valve surgery

Late recovery of sinus rhythm is unusual in patients with permanent AF treated by (radiofrequency) RF maze procedure during mitral valve surgery. Identification of clinical and instrumental preoperative factors predictive of early success of RF ablation in patients with permanent AF undergoing mitral valve surgery may improve selection of subjects to obtain long-term results. Hundred and thirty consecutive patients with permanent AF and mitral valve disease underwent modified RF maze procedure during concomitant mitral valve surgery. Rheumatic valve disease (61 pts) and mitral valve prolapse (41 pts) were the more common aetiology of valve abnormalities. Mitral valve replacement was performed in 54 % of patients and mitral valve repair in the remaining 46 %. Four patients died after surgery. At discharge, 87 patients (69 %) were in sinus rhythm (group 1) and 43 patients in AF persisted (group 2). At an average 24-month follow-up, sinus rhythm was present in 67 % of patients, and 33 % were in atrial fibrillation. In this period, late recovery of sinus rhythm was observed only in five patients, while eight discharged in sinus rhythm developed again atrial fibrillation. Among preoperative parameters at univariate analysis female sex, atrial fibrillation >24 months, left atrial diameter >54 mm, left atrial area >24 cm², rheumatic valve disease and NYHA class were associated with persistence of AF. At Cox regression multivariate analysis, increased left atrial area (OR 1.07 per unit increase—95 % CI 1.01–1.131) and rheumatic aetiology of valve disease (OR 4.52, 95 % CI 1.65–12.4) were associated with persistence of AF at hospital discharge. Persistence of AF after RF ablation in patients undergoing mitral valve surgery is related to aetiology, e.g. rheumatic valve disease, and to increasing left atrial diameter. Due to low rate of late recovery of sinus rhythm, indication to RF ablation associated with MV surgery should be carefully considered in patients with large atria and rheumatic mitral valve disease.     

Wavelength and Conduction Inhomogeneity in Each Atrium in Patients with Isolated Mitral Valve Disease and Atrial Fibrillation

INTRODUCTION: Patients with mitral valve disease frequently have atrial fibrillation (AF), and the left atrium is presumed to be the primary atrium that develops AF. However, it is still not clear whether the electrophysiologic abnormalities responsible for AF are confined to the left atrium in this subset of patients. METHODS AND RESULTS: To examine the AF vulnerability of each atrium, we measured the wavelength and inhomogeneity of the conduction at the lateral right atrium, lateral left atrium, and Bachmann's bundle after defibrillation of AF in seven patients undergoing the maze procedure and mitral valve surgery for AF and isolated mitral valve disease, respectively (AF group). The data were compared with five coronary surgery patients in sinus rhythm (SR group). The wavelength in the AF group was significantly shorter (P < 0.05) than in the SR group not only at the lateral left atrium (225 +/- 62 vs 285 +/- 36 mm) but also at the lateral right atrium (214 +/- 54 vs 254 +/- 34 mm). The variation coefficient of the local maximum activation phase difference in the AF group (1.9 +/- 0.8 at the right atrium, 2.1 +/- 0.8 at the lateral left atrium, and 2.0 +/- 0.6 at Bachmann's bundle) was significantly greater (P < 0.05) than in the SR group at all atrial regions. CONCLUSION: AF vulnerability was not confined to the left atrium immediately after defibrillation in AF patients with isolated mitral valve disease. Electrical remodeling resulting from perpetuation of AF, pathological changes extending to the right atrium, geometric changes caused by the atrial interactions occurring across the interatrial septum, or a combination of these may explain the results.     

二尖瓣置换术后患者持续性心房颤动心率控制与节律控制的对比分析

目的 研究风湿性心脏病(风心病)二尖瓣置换术后心率控制与节律控制对患者远期预后的影响.方法 本试验采用回顾性分析.选择2006年在我院择期行二尖瓣置换术的患者197例,按术后心律情况分为窦性心律组(n=100)和心房颤动(房颤)组(n=97).收集患者基本资料,以患者手术结束为试验起始时间,随访术后发生脑卒中及心脏性死...     

瓣膜置换术中双极射频消融治疗风湿性心脏病合并心房颤动

目的 探讨风湿性心脏瓣膜病合并心房颤动（AF）患者同期行瓣膜替换术及双极射频消融迷宫术的近期手术效果.方法 选取风湿性心脏瓣膜病合并心房颤动患者18例（消融组）,同期行瓣膜替换术及双极射频消融迷宫术治疗心房颤动.18例配对仅行心脏瓣膜替换术而未行双极射频消融迷宫术的患者作为对照组.患者年龄36～65岁,平均53.5岁,房颤持续时间1～10年,平均5年,左心房内径为44～67 mm.比较两组患者的手术治疗结果.结果 消融组18例患者术后窦性心律16例,房颤心律1例,结性心律1例;随访8个月,15例维持窦性心律,3例阵发性房颤心律.对照组13例术中心脏复跳后即为房颤心律,5例心脏复跳后为窦性心律,术后24 h内均转为房颤心律,应用胺碘酮不能持续恢复窦性心律.两组术后左房内径均较术前显著降低（P＜0.01）,消融组术后左房内径小于对照组[（33.06±2.88）mm比（36.16±2.43）mm,P＜0.05].结论 风湿性心脏瓣膜病合并慢性心房颤动患者在行瓣膜替换术的同时行附加的双极射频消融手术疗效良好,安全简便.     

The predictive value of chronic atrial fibrillation for the short- and long-term outcome after percutaneous mitral balloon valvotomy

BACKGROUND AND AIM OF THE STUDY: The predictive value of chronic atrial fibrillation (AF) before percutaneous mitral balloon valvotomy (PMBV) is still under discussion. The effect of the duration of chronic AF on short- or long-term results is not known. Therefore, we analyzed the predictive value of pre-procedural chronic AF and the duration of this rhythm disturbance for short- and long-term outcome after PMBV in patients with mitral valve stenosis. METHODS: A total of 140 PMBV procedures was performed in 137 patients with severe mitral stenosis. Sixty-three patients (45%) were in chronic AF; in 40 patients (63%) the AF was of more than one year duration. A successful procedure is defined as PMBV achieved without acute mitral valve replacement, and a mitral valve area after PMBV of > or =1.5 cm2. RESULTS: Patients in chronic AF were significantly older, had a larger left atrial diameter and higher NYHA functional class, compared with patients in sinus rhythm (SR). The success rates of PMBV were 80.5% and 77.6% in patients with SR and AF, respectively (p = NS). Mean follow up was 4.2+/-2.6 years (n = 127). At four years' follow up the event-free survival was 86.5% in patients with SR, and 78.5% in those with chronic AF at baseline (p = 0.031). Multivariate analysis of the entire study population showed the presence of chronic AF to be the only pre-procedural independent predictor for severe mitral regurgitation after PMBV (p = 0.030), as well for an event (p = 0.039) and restenosis (p = 0.034) during follow up. The risk for an event or restenosis during follow up increased seven-fold when chronic AF at baseline was present for more than one year (p = 0.010). CONCLUSION: Pre-procedural chronic AF is an independent predictor for unfavorable outcome at short- and long-term follow up after PMBV. A longer duration of AF further increases the risk of an event or restenosis.     

Atrial structural remodelling and restoration of atrial contraction after linear ablation for atrial fibrillation.

AIMS: We determined late atrial function following a surgical linear endocardial radiofrequency (RF) ablation procedure that aimed to restore and maintain sinus rhythm (SR) in atrial fibrillation (AF). We tested the hypothesis that successful restoration of SR is accompanied by measurable mechanical atrial function that is at normal or near normal levels. METHODS: Forty-seven patients who underwent the surgical RF procedure at least 6 months previously (median 2.86 years; range: 0.6-4.2 years) were studied using an array of echocardiographic variables. Two patient groups (SR restored [RF-SR], persistent AF [RF-AF]) and an age matched control group were studied. Among the echocardiographic variables measured were left atrial (LA) size and volume, LA active fractional emptying and mitral annular displacement corresponding to atrial contraction (A' velocity) by Doppler tissue imaging. RESULTS: At long term follow up 29/47of patients who underwent the RF procedure were in SR with atrial contraction present echocardiographically. Of the patients initially restored to SR, the proportion remaining in SR at 3 years was 79% (SE 9%). The atrial-emptying fraction was reduced in comparison to that seen in normal controls (27+/-14% vs 46+/-10%). The A' velocity was decreased in the surgical RF cohort vs controls (4.4+/-1.3 vs 9.7+/-1.7cm/s; P=0.0001). Despite LA size preoperatively being similar in both surgical groups, atrial size decreased in those in whom SR was restored (48.6+/-7.6 vs 44.8+/-4.7mm; P=0.0001) but increased in those in whom AF persisted (48.2+/-8.1mm vs 52.3+/-7.8mm; P=0.0001). CONCLUSION: The radial pattern of linear radiofrequency ablation used in the present study resulted in restoration of SR and atrial function. Procedural success was independent of preoperative atrial size. Restoration of SR results in 'reverse' atrial remodelling and improved atrial function. However atrial function remains modestly impaired, either due to the ablation lesions or pre-existing atrial disease.     

Effect of maze procedure in patients with atrial fibrillation undergoing valve replacement

BACKGROUND AND AIMS OF THE STUDY: The study aim was to elucidate the impact of the maze procedure on late outcome after valve replacement. METHODS: Between 1992 and 2000, 241 patients underwent the maze procedure combined with valve replacement. Patients were allocated to three groups: aortic valve replacement (AVR/maze, n = 16); mitral valve replacement (MVR/maze, n = 148); and combined aortic and mitral valve replacement (DVR/maze, n = 77). RESULTS: Mean follow up was 3.9 +/- 2.3 years. Hospital mortality was 0% in the AVR/maze group, 2.0% (n = 3) in the MVR/maze group, and 3.9% (n = 3) in the DVR/maze group. Elimination of atrial fibrillation (AF) at discharge was achieved in 74.3-75.9% of cases. Freedom from recurrence of AF/atrial flutter was 71.2% in the AVR/maze group, 68.2% in the MVR/maze group, and 64.0% in the DVR/maze group at five-year follow up. By multivariate analysis, risk factors for recurrence of AF/atrial flutter included preoperative enlarged left atrial dimension >70 mm, decreased postoperative fractional shortening <30%, and absence of postoperative left atrial contraction. Freedom from stroke was 93.6% in patients who achieved regular rhythm (normal sinus rhythm or junctional rhythm), and 80.9% in those with recurrence of AF at five years after surgery (p = 0.03). CONCLUSION: The combined maze procedure and valve replacement is safe and effective in selected patients. Restoration of regular rhythm significantly reduced the incidence of late stroke.     

Preoperative atrial size predicts the success of radiofrequency maze procedure for permanent atrial fibrillation in patients undergoing concomitant valvular surgery

BACKGROUND: The radiofrequency (RF) maze procedure can effectively restore sinus rhythm and atrial transport function in the majority of patients with permanent atrial fibrillation (AF) and mitral valve disease. No previous study has described a cutoff value of preoperative atrial size determined by the discriminant analysis in predicting the success of sinus conversion by the RF maze procedure for permanent AF in patients with mitral valve disease. METHODS AND RESULTS: This study included 81 patients with permanent AF and mitral valve disease who underwent the RF maze IV procedure while undergoing concomitant valvular operations. There was one surgical death (1.2%). Another patient died of acute necrotizing pancreatitis 13 months later. Two patients (2.5%) developed sick sinus syndrome and received transvenous permanent pacemaker implantation. In the remaining 77 patients, there were 38 men and 39 women, with a mean (+/- SD) age of 51 +/- 11 years. At a mean follow-up time of 38 months, 65 patients (84.4%) had persistent sinus conversion that had been accomplished by the RF maze procedure (group 1), and 12 patients (15.6%) did not regain sinus rhythm (group 2). We evaluated the preoperative variables between the two groups. Univariate analysis demonstrated that the preoperative left atrial area and the left atrial diameter of group 1 patients were significantly smaller than those of group 2 patients. Group 1 had significantly fewer patients associated with tricuspid valve disease than did group 2. By multiple stepwise logistic regression analysis, only the preoperative left atrial area was an independent determinant of sinus conversion by the RF maze procedure (odds ratio, 0.961; 95% confidence interval, 0.935 to 0.988; p < 0.005). Linear discriminant analysis demonstrated that the sensitivity and specificity of the cutoff value of 56.25 cm(2) of the preoperative left atrial area in predicting the sinus conversion by the RF maze procedure were 50.0% and 86.2%, respectively, and the positive and negative predictive values were 40.0% and 90.3%, respectively. CONCLUSION: The preoperative left atrial area is an independent determinant of sinus conversion by the RF maze procedure for patients with permanent AF and mitral valve disease.     

Short-term sinus rhythm predicts long-term sinus rhythm and clinical improvement after intraoperative ablation of atrial fibrillation

Aims: Our aim was to compare the long-term effects on rhythm and qualityof life (QoL) after left atrial epicardial radiofrequency (RF)ablation vs. no ablation in patients undergoing cardiac surgery. Methods and results: Thirty-nine patients with ECG documented atrial fibrillation(AF) scheduled for coronary artery bypass grafting (CABG) withor without concomitant valve surgery were consecutively electedfor epicardial RF ablation. Thirty-nine age- and gender-matchedpatients scheduled for CABG with or without concomitant valvesurgery only and with documented AF served as controls. Thefollow-up after ablation was 32 ± 11 months. The percentageof patients in sinus rhythm (SR) at long-term follow-up was62 vs. 33% (P = 0.03) after ablation and no ablation, respectively.SR at 3 months was highly predictive of that at 32 months (sensitivity95%, positive predictive value 86%). Long-term SR was associatedwith better QoL, fewer symptoms, higher ejection fraction, andsmaller left and right atria than AF. Conclusion: SR at 3 months was highly predictive of long-term SR that wasassociated with clinical improvement when compared with patientsstill in AF. AF at 3 months did not preclude a later stabilizationto SR.     

Long-term results of the maze procedure on left ventricular function for persistent atrial fibrillation associated with mitral valve disease

Although the maze procedure is often performed as a surgical treatment for atrial fibrillation (AF) combined with mitral valve surgery, the long-term efficacy of the maze procedure concerning cardiac function has not been determined. The aim of this study was to assess long-term results of the maze procedure for left ventricular function in patients with persistent AF associated with mitral valve disease. We analyzed 38 patients who underwent the maze procedure for persistent AF and mitral valve surgery. The cardiothoracic ratio on chest X-ray and the left atrial dimension, left ventricular end-diastolic dimension, left ventricular end-systolic dimension and left ventricular ejection fraction on transthoracic echocardiography were evaluated before and 6 years after the maze procedure. Twenty-two patients maintained sinus rhythm (SR group) and 16 patients had recurrence of permanent AF (AF group) after the maze procedure. Preoperative cardiac function and the methods of mitral surgery were similar between the two groups. At the latest follow-up, left ventricular function tended to be better in the SR group than in the AF group. Cardiovascular events occurred more often in the AF group during follow-up (50 vs. 18%, p < 0.05). This retrospective study revealed that maintaining the sinus rhythm after the maze procedure for patients who underwent mitral valve surgery might be important for preserving better long-term left ventricular function and result in fewer cardiovascular events.     

Live 3D TEE demonstrates and guides the management of prosthetic mitral valve obstruction

A 43-year-old woman, with a remote history of rheumatic mitral stenosis and a St. Jude prosthetic mitral valve replacement, presented with shortness of breath and palpitations, shortly after a long flight. On admission, atrial fibrillation with a rapid ventricular response was noted in the setting of a long history of noncompliance with her anticoagulation. Transesophageal echocardiography (TEE) demonstrated multiple laminated thrombi in the left atrial appendage. Live three-dimensional (3D) TEE confirmed this diagnosis and demonstrated an immobile posterior leaflet of the mitral prosthesis, which had direct implications in her management. She successfully underwent surgery for mitral valve replacement, left atrial appendage ligation, and a Maze procedure on the following day. The multiple thrombi within the atrial appendage were confirmed intraoperatively and pannus formation was determined to be the etiology of the leaflet immobility.     

Ablation of atrial fibrillation with mitral valve surgery

PURPOSE OF REVIEW: Recent advances in understanding of the pathogenesis of atrial fibrillation and development of new technology have resulted in a surge of interest in the surgical ablation of atrial fibrillation, particularly in patients with mitral valve disease. For patients with both mitral valve dysfunction and atrial fibrillation, a variety of new approaches are available to enable a complete operation that includes both mitral valve repair and ablation of atrial fibrillation. The purposes of this review are to review the rationale for surgical ablation of atrial fibrillation (AF) in mitral valve patients, describe the classic Maze procedure and its results, detail new approaches to surgical ablation of AF, emphasize the importance of the left atrial appendage, and consider challenges and future directions in the ablation of AF in mitral valve patients. RECENT FINDINGS: Left untreated, atrial fibrillation increases mortality and morbidity in patients undergoing mitral valve surgery. While the Maze procedure effectively eliminates atrial fibrillation in most of these patients, its complexity and increased operative time has precluded widespread application. New operations that use alternative energy sources to create left atrial lesion sets ablate atrial fibrillation in 60 to 80% of patients having mitral valve surgery. SUMMARY: In mitral valve patients with atrial fibrillation of more than 6 months' duration, the operative strategy should include both mitral valve surgery and ablation of atrial fibrillation. In many cases, these procedures can be performed minimally invasively. Refinements in mapping and ablation technology are on the horizon, and these will facilitate more widespread application of minimally invasive approaches and further improve results.