1. The closed heart MAZE: a nonbypass surgical technique
Richard Lee, MD, Takashi Nitta, MD, Richard B Schuessler, PhD, David C Johnson, MD, John P Boineau, MD, James L Cox, MD 
The Annals of Thoracic Surgery 
Volume 67, Issue 6, Pages (June 1999)
DOI: /S (99)

2. Fig 1
The basic technique for creating an atriotomy without cardiopulmonary bypass. First, 4-0 Prolene sutures are placed at the proximal and distal sites of the proposed lesion and a catheter is passed into and out of the atrium between them with the entrance and exit sites as close as possible to the knots. A mattress suture is then placed under the catheter and tied. This creates a tunnel of atrial tissue around the catheter (A and B). A wire is passed through the catheter with an uninsulated portion at the distal end of the tunnel (C). Application of electric cautery to a free end of the wire allows the surgeon to create an incision above the mattress suture (D). The incision is closed with an over-and-over stitch and the mattress suture is removed (E).
The Annals of Thoracic Surgery  , DOI: ( /S (99) )

3. Fig 2
The intersection of the linear incisions is performed by leaving the original temporary mattress suture in place and creating a 1-cm gap in the over-and-over repair at the proposed intersection site (A). The second intersecting lesion is performed through this gap as the catheter is passed below the first mattress stitch (B). A second mattress stitch is placed below the catheter (C). To minimize the gap after transection but before repair, the stitch is placed in the sequence 1 to 6 (in 1, out 2, in 3, out 4, in 5, out 6). The atriotomy is then performed through the gap between the two mattress sutures and then repaired in over-and-over fashion (D).
The Annals of Thoracic Surgery  , DOI: ( /S (99) )

4. Fig 3
The destruction of tissue at the annuli sites is created after careful dissection of the epicardial fat pad off the atrium to allow exposure to the annulus. The tunnel atriotomy is extended as close to the annulus as possible (A and B). The residual tissue is ablated by cryothermia on both the edocardial (C) and epicardial surface (D). When the epicardial cryothermia is applied, a rigid plastic catheter is simultaneously applied to the endocardium opposite the cryprobe and the tissue is elevated to help insulate the region from warm intraatrial blood (D).
The Annals of Thoracic Surgery  , DOI: ( /S (99) )

5. Fig 4
The amputation of the atrial appendage is performed by first making an incision as described above, passing the catheter through the gaps created by the atrial free wall lesions (A and B). However, after the mattress suture is placed under the catheter and the incision is made by the wire, the entire atrial appendage remains. Amputation is accomplished by simple surgical excision with scissors above the temporary mattress suture (C). Permanent approximation of the two ends is accomplished by an over-and-over repair (D).
The Annals of Thoracic Surgery  , DOI: ( /S (99) )

6. Fig 5
The incisions are created in the sequence 1 to 15 as described in the text. The “circle X’s” designate the areas to which cryothermia is applied. (IVC = inferior vena cava; LAA = left atria appendage; MV = mitral valve; PV = pulmonary veins; RAA = right atrial appendage; SVC = superior vena cava; TV = tricuspid valve.)
The Annals of Thoracic Surgery  , DOI: ( /S (99) )