A Comparative Study Between Different Surgical Techniques For Left Atrial Exclusion in Patients Undergoing Concomitant Cardiac Surgery.

OBJECTIVES

To find out the most successful surgical technique to obliterate left atrial appendage (LAA) in atrial fibrillation (AF) patients who had undergone concomitant cardiac surgery.

BACKGROUND

About 10%-65% of patients develop AF following cardiac surgery [Rho 2009; Mathew 2004; Maesen 2012]. Cerebral cardio-embolic stroke remains the most serious complication in AF patients. LAA is the main anatomical source for thromboembolic events. The use of oral anticoagulants (OAG) is considered to be an effective method for reduction of thromboembolic complications [Johnson 2000]. The use of oral anticoagulants is faced by two important facts which are the therapy duration is still unknown [Kirchhof 2017] and importantly that between 30-50% of patients are not candidates for oral anticoagulants due to the high bleeding risk or other contraindications [Johnson 2000; Kirchhof 2017; Kirchhof 2014]. In such patients, LAA obliteration would be an optimal alternative technique as it will reduce the stroke risk by 50% [Go 2014]. Several surgical techniques with variable degrees of success rates have been used.  It still is unclear which surgical technique is optimum to achieve a successful obliteration of the LAA and a considerable reduction of the postoperative stroke events in AF patients.

PATIENTS AND METHODS

A total of 100 patients have been subjected to surgical LAA exclusion from April 2017 to April 2019 in two different centers. All patients had postoperative transesophageal echo (TEE) examination to confirm the success of LAA occlusion. All patients included in our study suffered from AF at the time of surgery or in past history, which was confirmed by ECG examination in their previous medical files. A variety of surgical techniques to close the LAA have been utilized, including surgical excision by means of scissors, patch exclusion by means of an endocardial patch, suture exclusion and finally stapler exclusion. TEE examination 16 months postoperatively divided our patients into four groups as follows: successful LAA occlusion, Patent LAA, excluded LAA with persistent flow into LAA, and remnant LAA with a stump connection with LAA more than 1 cm.

RESULTS

Out of 100 patients, 30 patients (30%) underwent surgical LAA excision, 24 patients (24%) underwent surgical epicardial suture ligation, eight patients (8%) underwent patch exclusion using autologous pericardial patch, 33 patients (33%) underwent LAA internal orifice purse string suture obliteration, and five patients (5%) underwent stapler exclusion. Forty-two patients out of 100 (42%) showed successful LAA closure. The successful LAA occlusion occurred mostly in LAA excision patients 87%, 24% in LAA internal orifice purse string suture obliteration patients, 21% in epicardial suture ligation patients, and 37.5% in patch exclusion patients. The stapler exclusion was very disappointing as we did not record a single case out of the five patients who showed a successful LAA occlusion. Stroke events were recorded in all surgical techniques except the LAA excision technique. The stroke rate after two years follow up was zero in the surgical excision group, 49% in the suture exclusion group, 20% in the patch exclusion group, and 40% in stapler exclusion group.

CONCLUSION

Surgical LAA excision is the most successful technique for LAA occlusion and represents a promising technique for the reduction of thromboembolic events in AF patients who undergo a concomitant cardiac surgery.