Uncommon complication from left atrial appendage occluder (LAAO)

To decrease the risk of stroke due to atrial fibrillation, cardiologists will insert a device known as a left atrial appendage occluder to the left atrial appendage. This will decrease the stagnant flow of blood in that particular region. Known complications of this procedure include perforation, migration and dislodgement.We report a case with uncommon late complication of this device causing erosion of the left ventricle, in which open heart operation was carried out to repair the defect.     

Left atrial appendage perforation with Watchman device implantation: Strategies for surgical repair

Percutaneous occlusion of the left atrial appendage is increasingly being used as an alternative for stroke prevention in patients with non‐valvular atrial fibrillation at high risk of complications from long term anticoagulation. We describe a case of left atrial appendage perforation during Watchman device implantation requiring emergency repair of the left atrium using sternotomy and cardiopulmonary bypass. Technical considerations for surgical decision making are discussed; in hemodynamically unstable patients as well as those at high risk for embolization.     

改良Mini-Maze手术患者左心耳组织PITX2及KCNQ1蛋白表达特点分析及其临床相关性分析

目的 通过检测改良Mini-Maze手术心房颤动(房颤)患者左心耳组织PITX2及KCNQ1蛋白表达水平,结合临床数据对不同类型房颤的临床危险因素进行分析.方法 收集2017年2月至2018年8月因房颤于本中心行手术患者共59例的左心耳组织,其中58例行改良Mini-Maze手术,即双侧微创切口下行双极射频消融术、双侧...     

Impact of the maze procedure on the stroke rate in patients with atrial fibrillation.

OBJECTIVE: The incidence of stroke associated with atrial fibrillation, even in high-risk patients, can be reduced significantly by adequate anticoagulation. However, anticoagulation does not abolish the stroke rate, and unfortunately only 40% of patients with atrial fibrillation actually receive anticoagulant therapy, even in areas where adequate health care is available. METHODS: During the past 11.5 years, we have performed the maze procedure for the treatment of medically refractory atrial fibrillation in 306 patients, 58 of whom presented with a history of having had a stroke (n = 40) or transient ischemic attack (n = 18) before surgery. All patients with atrial fibrillation are at an increased risk for these complications, but they are especially prevalent in those patients with previous thromboembolic events and those with other recognized risk factors. RESULTS: Among the 306 patients who had surgery, there were only 2 perioperative strokes (0. 7%), and in the 265 patients followed for up to 11.5 years after the maze procedure, there has been only 1 late minor stroke that has now completely resolved. CONCLUSIONS: The ability of the maze procedure to decrease the risk of stroke associated with atrial fibrillation so dramatically is likely due to the restoring of sinus rhythm and atrial transport function in combination with surgical removal or obliteration of the left atrial appendage, where most thrombi associated with atrial fibrillation develop.     

The left atrial appendage: our most lethal human attachment! Surgical implications

Objectives: To prevent death from atrial fibrillation, a cardiac disease which kills by producing emboli. Atrial fibrillation causes about 25% of strokes and increases stroke rate by five times. Over 90% of these embolic strokes are from clots originating in the left atrial appendage. This study addresses the surgical feasibility of removing the appendage to prevent future deaths in two subcategories of patients. (1) Prophylactic removal during open-heart surgery to study its safety. Theoretically, as these patients age and some develop atrial fibrillation, protection from embolic strokes would already be present. (2) Therapeutic removal in chronic atrial fibrillation patients by means of a thorascopic approach. Its technical feasibility is demonstrated. Its actual stroke prevention potential awaits large studies. Methods: Appendectomy has been evaluated three ways. (1) Experimentally, thorascopic appendage removal was performed on 20 goats with endoscopic approach. Late studies showed a cleanly healed atrial closure after stapling, and no puckering of tissue as seen with the purse-string approach. (2) Safety of human appendectomy was demonstrated in 437 patients (1995–1997). Routine appendectomy was performed during open-heart surgery. Forty-three appendages were stapled, 391 sutured off. (3) Thorascopic appendectomy in seven patients with chronic atrial fibrillation has been successfully accomplished as an isolated surgical procedure. Stapling or suture closure provides a much cleaner, non-puckered suture line than a purse string. Results: In prophylactic removal, no acute bleeding occurred. No late problems have been identified. Endoscopic removal of the appendage has been successful in seven atrial fibrillation patients. Conclusions: The left atrial appendage is a lethal source of emboli in atrial fibrillation patients. As patients age and often develop atrial fibrillation, prophylactic appendage removal whenever the chest is open is suggested as a method to prevent future strokes. In chronic atrial fibrillation patients, appendectomy can be done with a mini-thorascopic approach. Further studies are planned to demonstrate the effectiveness of appendectomy in preventing strokes in the chronic fibrillating patients.     

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.     

Minimally invasive,simplified double-layer left atrial appendage closure

The left atrial appendage (LAA) has been identified as a site of thrombus formation in the heart and as a source of embolism in patients with atrial fibrillation, leading to stroke. Studies suggest that LAA closure may reduce the risk for stroke and the need for anticoagulation; conversely, incomplete closure can increase the stroke risk almost 12-fold. Because open heart surgery is associated with increased risk for subsequent stroke, surgeons generally prefer to close the LAA during heart surgery, as recommended in current atrial fibrillation management guidelines. Building on trends toward minimally invasive approaches in cardiac surgery, we developed a simple, unique, and reproducible method for complete LAA closure during mitral valve surgery that has proven to be safe and efficacious: Our first three patients remained completely free from stroke and minor neurological manifestations 27 months after surgery.     

Assessing the immediate and sustained effectiveness of circular epicardial surgical ligation of the left atrial appendage

Abstract Background/Aim: Obliterating the left atrial appendage from systemic circulation in patients with atrial fibrillation has been proposed to reduce thromboembolic events. The goal of this study was to assess the effectiveness of a circular method of epicardial surgical ligation in obliterating the left atrial appendage and maintaining sustained exclusion. Methods: Patients with permanent atrial fibrillation and an indication for elective cardiac surgery were enrolled. All patients underwent preoperative cardiac gated computerized tomography (CT) and transesophageal echocardiography (TEE). During the cardiac procedure circular ligation of the appendage was performed. Results: Twelve patients, mean (SD) age 65 (12) years completed the study. Intraoperative TEE demonstrated all patients (12/12) had complete postligation occlusion of the left atrial appendage. At three‐month follow‐up, cardiac gated CT demonstrated that 75% (9/12) of the patients had communication of contrast dye from the left atrial appendage to body of left atrium. Left atrial appendage orifice area and volume were reduced from mean (SD) (5.5 cm²[1.8] to 0.5 cm²[0.4] p = 0.002) and (14.0 cm³[8.3] to 2.7 cm³[1.3] p = .005) postligation, respectively. No clinically significant thromboembolic events were reported. Conclusions: Epicardial suture ligation of the left atrial appendage resulted in successful intra‐operative exclusion on TEE; however, a significant portion of patient's demonstrated communication of contrast on CT. This is suggestive of incomplete long‐term exclusion. The clinical significance of reduction in left atrial appendage orifice area and volume with a persistent communication requires further study.     

Early and late stroke after mitral valve replacement with a mechanical prosthesis: risk factor analysis of a 24-year experience

OBJECTIVE: We evaluated risk factors for mortality and stroke after mechanical mitral valve replacement between May 1977 and December 2001. METHODS: Early and late mortality and stroke were assessed. Potential predictors of mortality and stroke were entered into a Cox proportional hazards model. Actuarial survival and freedom from stroke were determined by a log-rank test. RESULTS: Mitral valve replacement was performed in 812 patients. Concomitant procedures included left atrial appendage closure in 493 (61%) patients, tricuspid annuloplasty-replacement in 348 (43%) patients, maze procedure in 185 (23%) patients, plication of the left atrium in 148 (18%) patients, and other procedures in 151 (19%) patients. Five-year actuarial survival was 91.1% +/- 2.3%. Freedom from stroke at 8 years was significantly better in patients with sinus rhythm versus atrial fibrillation (P <.001). Ninety-nine percent of patients with mitral valve replacement combined with a maze procedure were free from stroke, whereas only 89% of patients with mitral valve replacement alone were free from stroke at 8 years after surgical intervention. Seventy-two patients had late stroke; sixty-five patients (90%) were in atrial fibrillation, and 47 (65%) patients had the left atrial appendage closed. Multivariate analysis showed that late atrial fibrillation (odds ratio, 3.39; 95% confidence interval, 1.72-6.67; P =.0001) and omission of the maze procedure (odds ratio, 3.40; 95% confidence interval, 1.14-10.14; P =.003) were the significant risk factors for late stroke. CONCLUSIONS: Persistent atrial fibrillation was the most significant risk factor for late stroke after mechanical mitral valve replacement. Restoration of sinus rhythm with a maze procedure nearly eliminated the risk of late stroke, whereas neither closure of the left atrial appendage nor therapeutic anticoagulation prevented this complication.     

Surgery for atrial fibrillation: recent progress and future perspective

Development and introduction of radiofrequency ablation devices allowed the maze procedures to be performed safely and easily, further enabling off-pump pulmonary vein isolation through a mini-thoracotomy or thoracoscope. The effects of the maze procedure include prevention of stroke and other complications related to atrial fibrillation, improved cardiac performance, and relief of symptoms. Indications for the maze procedure have been discussed on the basis of the evidence. Pulmonary vein isolation has been shown to be effective in most patients with paroxysmal atrial fibrillation and can be performed with endocardial catheter ablation and minimally invasive epicardial ablation. These two modalities should be compared in terms of the success rate, occurrence of cerebral microembolic signals, capability of additional lesions indicated for persistent or long-standing persistent atrial fibrillation, and closure of the left atrial appendage. Noncontinuous or nontransmural lines of conduction block as a result of incomplete ablation can result in recurrence of atrial fibrillation and induction of atrial tachycardia. Intraoperative verification of conduction block across the ablation lines is recommended to prevent these complications. Volume reduction of the enlarged left atrium or a boxlesion to isolate the entire posterior left atrium may be effective in patients with a dilated left atrium, but the potentially impaired atrial transport function should be considered. Mapping of active ganglionated plexi and their ablation may improve the outcome of the procedure, but the long-term effect on atrial fibrillation and autonomic nerve activities should be examined.     

Use of tissue welding technology to obliterate left atrial appendage--novel use of Ligasure

The left atrial appendage is one source of thromboemobolus. Complete occlusion of this appendage is required to sever communication with the left atrium; however, current ligation techniques can potentially leave residual communication. A novel technique of occluding the appendage has been developed using a bipolar device and radiofrequency energy. Twelve patients underwent an off-pump, epicardial Maze procedure using radiofrequency ablation. As an adjunct to the procedure, ligation of the left atrial appendage was completed using the LigaSure Xtd (Valleylab, Tyco Healthcare, Boulder, CO) with a modified application technique. Patients were followed to ensure sinus or paced rhythm. All twelve patients are in sinus or paced rhythm upon follow-up. Four patients required pacemakers for sick sinus syndrome. To date there have been no incidents of strokes, thromboembolic events, postoperative bleeding or deaths in all patients. Complete occlusion of the left atrial appendage is necessary to eliminate communication, which is accomplished by this radiofrequency, bipolar device. Extensive studies are necessary to verify the efficacy of this novel occluding technique.     

Congenital aneurysm of the left atrial appendage

Aneurysm of the left atrial appendage (LAA) is very infrequent. We present the case of 24-year-old man in functional class I with atrial fibrillation but no other symptoms. Radiology showed an abnormality in the outline of the heart. Echocardiography revealed left appendage aneurysm. After median sternotomy, aneurysmectomy was performed under cardiopulmonary bypass without cross clamping. Atrial fibrillation ceased as soon as the aneurysm had been removed. There were no postoperative complications. Three months later the patient remained asymptomatic and in sinus rhythm.     

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.     

Map-guided surgery for atrial fibrillation

BACKGROUND: Although current surgical procedures result in a high success rate for atrial fibrillation, they are not guided by electrophysiologic findings in individual patients and thus might include unnecessary incisions in some patients or be inappropriate for other patients. We sought to determine whether intraoperative mapping is beneficial for the surgical treatment of atrial fibrillation. METHODS: A 256-channel 3-dimensional dynamic mapping system with custom-made epicardial patch electrodes was used to examine the atrial activation during atrial fibrillation and to determine the optimal procedure in 37 patients with continuous and 9 patients with intermittent atrial fibrillation intraoperatively. RESULTS: Surgical intervention for atrial fibrillation was not indicated in 3 patients in whom the atrial electrograms had a low voltage over a broad area. Concurrent, multiple, and repetitive activations arising from the pulmonary veins or left atrial appendage were observed in all patients. A simple left atrial procedure consisting of pulmonary vein isolation and left atrial incisions without any right atrial incisions was performed in 8 patients in whom the right atrial activation was passive, and all (100%) were cured of atrial fibrillation. The radial procedure was performed in the remaining 35 patients, and 31 (89%) of the patients were cured of atrial fibrillation. In this subset of patients, 10 exhibited reentrant or focal activation in the posterior left atrium between the right and left pulmonary veins and required an additional linear ablation on the posterior left atrium. The total amount of postoperative bleeding after the simple left atrial procedure was significantly less than after the radial procedure (378 +/- 135 vs 711 +/- 364 mL, P = .03). The right and left atrial transport functions were well preserved after both the radial and simple left atrial procedures. CONCLUSION: Intraoperative mapping facilitates determining the optimal procedure for atrial fibrillation in each patient.     

Use of intraoperative transesophageal echocardiography to predict atrial fibrillation after coronary artery bypass grafting

BACKGROUND: Postoperative atrial fibrillation in coronary artery bypass graft surgery occurs in 10-40% of patients. It is associated with a significant degree of morbidity and results in prolonged lengths of stay in both the intensive care unit and hospital. METHODS: The authors prospectively evaluated patients undergoing coronary artery bypass with detailed transesophageal echocardiography examinations conducted before and after cardiopulmonary bypass to study whether risk factors for atrial fibrillation could be identified. Demographic and surgical parameters were also included in the analysis. Selected variables were subjected to univariate and subsequent multivariate analyses to test for their independent or joint influence on atrial fibrillation. RESULTS: Seventy-nine patients had assessable transesophageal echocardiography examinations. Significant univariate predictors of atrial fibrillation included advanced age (P = 0.002), pre-cardiopulmonary bypass left atrial appendage area (P = 0.04), and post-cardiopulmonary bypass left upper pulmonary vein systole/diastole velocity ratio (P = 0.03). When these three factors were considered together in a multiple logistic regression analysis, left upper pulmonary vein systole/diastole velocity ratio was a significant predictor (P < 0.05), as was the joint effect of age plus pre-cardiopulmonary bypass left atrial appendage area (P = 0.005). The probability of developing atrial fibrillation for the combination of age = 75 yr, post-cardiopulmonary bypass left upper pulmonary vein systole/diastole velocity ratio = 0.5, and left atrial appendage area = 4.0 cm was 0.83 (95% confidence interval, 0.51-0.96). CONCLUSIONS: Early identification of patients at risk for postoperative atrial fibrillation may be feasible using the parameters identified in this study.     

Thoracoscopic radiofrequency pulmonary vein isolation and atrial appendage occlusion

A 46-year-old woman with a 7-year history of profoundly symptomatic daily paroxysmal atrial fibrillation had undergone two percutaneous catheter ablations and multiple medication trials. With informed consent, bilateral pulmonary vein isolation and left atrial appendage occlusion as well as ablation of ganglionated plexi were performed by a totally thoracoscopic technique employing a bipolar radiofrequency device. She was discharged home on postoperative day 3 and had one brief episode of atrial fibrillation 1 week later, but has had no further atrial fibrillation for more than 6 months since the procedure.     

Off-pump epicardial compartmentalization for ablation of atrial fibrillation

The Cox-Maze-III procedure still remains the gold standard in surgical treatment of atrial fibrillation. The major hazard of atrial fibrillation is thromboembolic event to the brain. Left atrial appendage (LAA) represents the source of thrombus and subsequent embolism although LAA obliteration is a key point to prevent thrombogenesis. We describe a simplified off-pump compartmentalization procedure using epicardial radiofrequency ablation of the left atrium and LAA stapling on the beating heart without cardiopulmonary bypass.     

Stroke prevention as an indication for the Maze procedure in the treatment of atrial fibrillation

The Maze procedure has proven to be extremely effective in curing medically refractory atrial fibrillation. This analysis of our surgical results with the Maze procedure indicates that the Maze procedure, with or without associated cardiac surgery, has the lowest perioperative stroke rate of any major cardiac surgical procedure. This is surprising in view of the fact that all of the patients who undergo the Maze procedure have an elevated risk of stroke because of the presence of atrial fibrillation. In addition, many of the patients have already had strokes, further increasing the likelihood of perioperative stroke. Only 1 patient has had a stroke in the 12-year follow-up period following the Maze procedure. This is comparable to the risk of stroke in the general population and indicates that the Maze procedure essentially abolishes the risk of stroke associated with atrial fibrillation.     

Epicardial left atrial appendage clip occlusion also provides the electrical isolation of the left atrial appendage

OBJECTIVES The exclusion of the left atrial appendage (LAA) has been used to reduce the risk of stroke associated with atrial fibrillation (AF). While LAA exclusion has been associated with a reduced risk of stroke, the effect on the electrical activity of the LAA (a potential source of AF) remains unknown. As such, we sought to demonstrate whether surgical epicardial clip occlusion leads to the electrical isolation of the LAA. METHODS From December 2010 until August 2011, 10 patients with paroxysmal AF underwent off-pump coronary artery bypass surgery with bilateral pulmonary vein isolation and an LAA clip occlusion with a new epicardial clip. Before and after the clip was placed, pacing manoeuvres were performed to assess the electrical exit and entry blocks from the LAA. RESULTS All clips were applied successfully. The mean procedure time for the clip application was 4?±?1?min. No complications occurred related to clip application. Prior to the pericardial closure, 18?±?3?min after the clip placement, the LAA stimulation and pacing manoeuvres demonstrated complete electrical isolation of the LAA in all cases. CONCLUSIONS Epicardial LAA clip occlusion leads to the acute electrical isolation of the LAA and may not only provide stroke prevention but also reduce the recurrence of AF.     

Minimal invasive endoscopic resection of a giant left atrial appendage aneurysm

We report a case of a 35-year-old male patient who presented with chronic atrial fibrillation secondary to a massive congenital left atrial appendage aneurysm. Minimal invasive endoscopic resection of the left atrial aneurysm with cryoablation was performed. The patient was discharged home in sinus rhythm.