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.     

Staple closure of the left atrial appendage

Closure of the fibrillating left atrial appendage has been recommended during mitral valve repair or replacement to prevent systemic emboli postoperatively. Closure of the left atrial appendage has been accomplished in the past by direct intra-atrial suture or by external ligation. The authors have used the TA-55 automatic stapler in 40 patients to close the left atrial appendage during mitral valve surgery. In all patients the closure was effected successfully at the first attempt without complication.     

Mitral valve replacement through a giant left atrial appendage

We report a rare case of a 45-year-old male with a giant left atrial appendage (13x10 cm in size) and chronic massive regurgitation at the mitral valve. Massive dilatation was compressing most of the left lower lobe and the large size of the appendage was pushing the mediastinum to the right. Therefore under median sternotomy, the mitral valve was clearly accessible and chordal sparing mitral valve replacement with left atrial plication was successfully performed through the giant left atrial appendage.     

Isolated papillary endothelial hyperplasia in the left atrial appendage

Papillary endothelial hyperplasia (PEH) of the heart is extremely rare. This report describes a case of left atrial appendage PEH discovered by intraoperative palpation during mitral valve repair in a 69-year-old woman. The lesion was treated successfully by surgical excision of the left atrial appendage. Immunohistochemistry analysis confirmed the diagnosis and the patient was discharged without any complications.     

Left atrial reduction plasty: a novel technique

We describe a novel technique of left atrial volume reduction in a patient presenting with severe dyspnea from severe mitral insufficiency, giant left atrium, and compressive symptoms of dysphagia and dysphonia. Resection involved circumferential excision of the left atrium anterior to the pulmonary venous vestibule and posterior to the mitral valve and fossa ovalis, including the left atrial appendage. A chordal-sparing bioprosthetic mitral valve replacement, tricuspid valve annuloplasty, and coronary bypass were also performed. Significant reduction of left atrial volume by 50% was achieved and clinical resolution of compressive symptoms was seen at 6-month follow-up.     

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.     

Recanalization of the Left Atrial Appendage Demonstrated by Transesophageal Echocardiography

Closure of the fibrillating left atrial appendage has been recommended during mitral valve operations to help prevent thrombus formation and systemic embolization postoperatively. We report recanalization of the appendage orifice in 6 patients after surgical closure by purse-string suturing at the time of mitral valve replacement. Transesophageal echocardiography demonstrated disruption of the closure line and partial recanalization of the sutured orifice with relatively high velocity flow between the left atrial body and the appendage.     

Early degeneration of a bioprosthetic mitral valve complicated by a large left atrial thrombus

The authors report the case of a patient with symptomatic early bioprosthetic mitral valve deterioration in the setting of calcium supplementation. This was further complicated by a large left atrial thrombus despite supratherapeutic anticoagulation and a previously oversewn left atrial appendage. As mechanical valves are less predisposed to calcification in comparison with bioprosthetic implants, the patient underwent a mechanical mitral valve replacement in addition to a left atrial thrombectomy.     

Ligation of the Left Atrial Appendage Using an Automatic Surgical Stapler

We investigated the use of an automatic surgical stapler for ligation of the atrial appendage in sheep, and then applied this technique in patients. Fourteen adult sheep underwent ligation of the left atrial appendage using a surgical stapler with a rotating head and either absorbable or stainless steel staples. In 4 sheep, killed after two hours, no hemorrhage or intraatrial thrombus was observed acutely. Ten sheep were allowed to recover for 90 to 100 days, twice the expected absorption time of absorbable staples. There was complete obliteration of the left atrial appendage without evidence of intraatrial thrombus or staple migration. The absorbable staples were completely reabsorbed. We subsequently used this technique in 5 patients undergoing mitral valve procedures. There were no complications, and adequate obliteration of the atrial appendage was achieved.     

Mitral stenosis with free-floating left atrial thrombus and recurrent systemic embolisation. A case report

A 64-year-old white woman with moderately severe rheumatic mitral stenosis complicated by atrial fibrillation and recurrent systemic embolisation to the brain was found at operation to have a large 'free-floating' left atrial thrombus, as well as multiple left atrial appendage thrombi. These had not been detected by echocardiography. She also had significantly reduced left ventricular contractility on cine angiography, and right coronary artery atherosclerosis. She underwent successful mitral valve replacement and excision of the left atrial appendage.     

Radical surgery for a mitral valve intimal sarcoma: serial patch repair of the annulus and atrium

We report the rare case of a 48-year-old woman with a cardiac intimal sarcoma occupying the mitral valve and the left atrial roof. We resected the tumour in one block without residual lesions. The anterior mitral annulus and left atrial roof were serially repaired with the bovine pericardium, and a mechanical prosthesis was implanted in the reconstructed mitral annulus. The patient remains alive without recurrence for more than 1 and a half years postoperatively. We performed radical surgery for a mitral valve intimal sarcoma, and serial patch repair of the anterior mitral annulus and left atrial roof was a useful technique.     

Mitral valve repair robotic versus sternotomy.

OBJECTIVE: Robotically assisted mitral valve repair were compared with sternotomy mitral valve repair. Prospectively we evaluated safety and efficacy in performing simple mitral repairs. METHODS: Between February 2004 and September 2005, 25 patients with posterior leaflet insufficiency underwent mitral valve repair using the da Vinci system. They were matched retrospectively with 25 patients who underwent the same repair via a median sternotomy. The minimal invasive repairs were performed with peripheral cardiopulmonary bypass, transthoracic aortic cross-clamp, and antegrade cardioplegia. Repair was performed with two ports and a 4-cm intercostals lateral incision in the right chest for access. All patients had posterior leaflet resection and placement of a ring annuloplasty. RESULTS: All patients had successful valve repairs. There were no deaths. There was one conversion to an extended thoracotomy in the minimal invasive group due to a bleeder on the left atrial appendage. Overall mean study times showed a longer aortic cross-clamp (range, 96.1 min vs 69.6 min) and cardiopulmonary bypass (range, 122.1 min vs 85.7 min) for the minimal invasive group. Length of stay was less for the minimal group (7 days vs 9 days). At postoperative echocardiography two patients in both group developed 2+ mitral regurgitations. All other patients had a competent mitral valve repair with no insufficiency. CONCLUSIONS: Simple mitral valve repair can be successfully performed with the da Vinci robotic system. This approach is as safe as a sternotomy and long-term follow-up is needed to determine the durability of the mini invasive repair.     

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.     

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.     

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.     

The Leipzig experience with robotic valve surgery

OBJECTIVES: The study describes the single-center experience using robot-assisted videoscopic mitral valve surgery and the early results with a remote telemanipulator-assisted approach for mitral valve repair. MATERIAL AND METHODS: Out of a series of 230 patients who underwent minimally invasive mitral valve surgery, in 167 patients surgery was performed with the use of robotic assistance. A voice-controlled robotic arm was used for videoscopic guidance in 152 cases. Most recently, a computer-enhanced telemanipulator was used in 15 patients to perform the operation remotely. RESULTS: The mitral valve was repaired in 117 and replaced in all other patients. The voice-controlled robotic arm (AESOP 3000) facilitated videoscopic-assisted mitral valve surgery. The procedure was completed without the need for an additional assistant as "solo surgery." Additional procedures like radiofrequency ablation and tricuspid valve repair were performed in 21 and 4 patients, respectively. Duration of bypass and clamp time was comparable to conventional procedures (107 A 34 and 50 A 16 min, respectively). Hospital mortality was 1.2%. Using the da Vinci telemanipulation system, remote mitral valve repair was successfully performed in 13 of 15 patients. CONCLUSION: Robotic-assisted less invasive mitral valve surgery has evolved to a reliable technique with reproducible results for primary operations and for reoperations. Robotic assistance has enabled a solo surgery approach. The combination with radiofrequency ablation (Mini Maze) in patients with chronic atrial fibrillation has proven to be beneficial. The use of telemanipulation systems for remote mitral valve surgery is promising, but a number of problems have to be solved before the introduction of a closed chest mitral valve procedure.     

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.     

Video-assisted bilateral pulmonary vein isolation and left atrial appendage exclusion for atrial fibrillation

OBJECTIVE: Pulmonary vein isolation is curative in selected patients with atrial fibrillation. The objective of this study was to assess the feasibility and safety (midterm results) of video-assisted thoracoscopic epicardial pulmonary vein isolation. METHODS: Twenty-seven patients (22 male patients) with atrial fibrillation (18 paroxysmal, 4 persistent, and 5 permanent; average age, 57 years) underwent bilateral video-assisted thoracoscopic off-pump epicardial pulmonary vein isolation and exclusion of the left atrial appendage. All patients had had unsuccessful drug therapy or were intolerant to antiarrhythmic drug therapy or were intolerant to warfarin. The approach included two 10-mm ports and one 5-cm working port (non-rib spreading) bilaterally. Pulmonary vein isolation was achieved bilaterally by using a bipolar radiofrequency device. The left atrial appendage was excised with a surgical stapler. RESULTS: Bilateral pulmonary vein isolation and left atrial appendage excision was performed successfully in all patients. There were no conversions to sternotomy or thoracotomy. All patients were extubated in the operating room. Postoperative complications in 3 patients were minor and resolved within 48 hours. One morbidly obese patient had more serious complications related to comorbid conditions. Average postoperative follow-up is approximately 6 months (173.6 days). Twenty-three patients have been followed up for greater than 3 months, and 21 of these patients are free of atrial fibrillation (91.3%). The results of magnetic resonance angiography were normal (no pulmonary vein stenosis) in 12 of 12 patients evaluated 3 to 6 months postoperatively. CONCLUSIONS: Bilateral video-assisted thoracoscopic pulmonary vein isolation with excision of the left atrial appendage is feasible and safe and offers a promising, new, minimally invasive, beating-heart approach for curative surgical treatment of atrial fibrillation.     

The use of PTFE graft to correct anomalous drainage of persistent left superior vena cava

A new technique to correct persistent left superior vena cava (LSVC) drainage into the left atrium is described in a 14-year-old patient with situs inversus, left atrial isomerism common atrium, and mitral valve regurgitation. During surgery, occlusion of the LSVC markedly increased the venous pressure, precluding its ligation. Because of the malposition of the heart and the unusual atrial anatomy, correction with an intra-atrial baffle was not attempted. After correcting the intra-cardiac anomaly, the LSVC was divided and anastomosed to the "right" atrial appendage using a segment of PTFE graft. The postoperative course was uneventful and an angiogram demonstrated excellent performance of the graft.     

Transaortic delivery of the transmitral lesion in a complete maze procedure

A 68-year-old hypertensive diabetic woman with chronic atrial fibrillation presented with progressive congestive symptomatology. She was diagnosed with severe aortic stenosis, moderate mitral regurgitation, and critical right coronary artery stenosis. In addition to coronary revascularization and bioprosthetic aortic valve replacement, she underwent a mitral valve repair and a complete cryoMaze procedure through a transaortic approach. This technique obviates a separate left atriotomy for the mitral repair and Maze procedure. It affords excellent exposure, while reducing cross clamp and cardiopulmonary bypass time as well as avoiding the potential sequelae of bleeding and traction injuries resulting from a left atriotomy.