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Innovative Monolateral Approach for Closed-Chest Atrial Fibrillation Surgery
Innovative Monolateral Approach for Closed-Chest Atrial Fibrillation Surgery Gianluigi Bisleri, MD, and Claudio Muneretto, MD Division of Cardiac Surgery, University of Brescia Medical School, Brescia, Italy
Surgical treatment of atrial fibrillation recently gained new popularity since the introduction of different energy sources as an alternative to the original cut-and-sew technique. Recently an innovative approach for closedchest thoracoscopic epicardial pulmonary veins isolation has been described for patients suffering from lone atrial
fibrillation. Nevertheless in an effort to further reduce the invasiveness of closed-chest atrial fibrillation surgery, we developed a novel monolateral approach for thoracoscopic arrhythmia surgery. (Ann Thorac Surg 2005;80:e22–5) © 2005 by The Society of Thoracic Surgeons
S
space on the anterior axillary line, whereas the two other instrument ports are slightly anterior, on the third and fifth intercostal spaces, outside the triangle connecting the camera port, the jugular notch, and the xiphoid. We conventionally use a 0° 10-mm scope (Karl Storlz, Tuttlingen, Germany) as the endoscopic camera. Similarly, marking of the same intercostal spaces on the left thorax is carried out in case a conversion to the bilateral approach should occur. The patient is then positioned approximately 30° toward the left decubitus. After right lung deflation, three 10-mm ports (Ethicon Endo-Surgery, Cincinnati, OH) are placed on the right hemithorax, CO2 insufflation is started (intrathoracic pressure, 10 to 12 mm Hg), and the pericardium is longitudinally opened 1 to 2 cm above the phrenic nerve. First, a wide dissection between the superior vena cava, and the right superior pulmonary vein is carried out by means of an endopeanut blunt dissector (US Surgical, Norwalk, CT); then the pericardial reflection between the inferior vena cava and the right inferior pulmonary vein is also dissected in a similar fashion. An 8-French catheter conventionally used for percutaneous transluminal coronary angioplasty (PTCA) procedures (model JR 4.0 [Guidant, Santa Clara, CA]) is then introduced through the inferior port and advanced into the transverse sinus through the pericardial opening between the superior vena cava and the right superior pulmonary vein (Fig 2A). Typically, the PTCA catheter is visible over the surface of the right ventricle and up to the right atrium (Fig 2B). The tip of the PTCA catheter is then grasped and advanced into the oblique sinus along the surface of the diaphragm. Once the tip of the catheter is visualized through the pericardial opening between the inferior vena cava and the right inferior pulmonary vein, it can be retrieved and pulled out from the chest (Fig 3A). Catheter
ince its introduction in 1989 by Cox and colleagues [1], surgical treatment of atrial fibrillation (AF) experienced a new dawn during the past few years, mainly thanks to the use of various energy sources and lesion sets that simplified the complex original maze technique. However in the majority of cases the cure of AF was associated with surgical treatment of concomitant structural cardiac diseases (ie, mitral or aortic valve or coronary disease) and was approached through a conventional sternotomy. Recently different authors described an innovative technique for closed-chest thoracoscopic epicardial pulmonary vein isolation for patients suffering from lone AF [2– 4]. Nevertheless in an effort to further reduce the invasiveness of closed-chest AF surgery, we developed a novel monolateral approach for thoracoscopic arrhythmia surgery. The main goal of the procedure lies in the possibility to effectively and safely position a microwave ablation probe around the four pulmonary veins as in the conventional bilateral approach, although only the right chest is entered.
Technique After anesthetic sedation, the patient is intubated with a double-lumen endotracheal tube for selective lung ventilation. Transesophageal echocardiography is routinely performed in order to rule out the presence of thrombi in the left atrial appendage (LAA). The patient is placed in the supine position with a square pad placed behind the back at the scapular level, with the arms along both sides of the body. Draping is then carried out in standard fashion as for a conventional bilateral thoracoscopic case. The third, fourth, and fifth intercostal spaces of the right thorax are marked for port positioning as depicted in Figure 1; briefly the camera port is positioned at the level of the fourth intercostal Accepted for publication June 3, 2005. Address correspondence to Dr Bisleri, UDA Cardiochirurgia–Spedali Civili, P.le Spedali Civili, 1, Brescia, 25123 Italy; e-mail: gianluigi_bisleri@ katamail.com.
© 2005 by The Society of Thoracic Surgeons Published by Elsevier Inc
Drs Bisleri and Muneretto disclose that they have a financial relationship with Guidant.
0003-4975/05/$30.00 doi:10.1016/j.athoracsur.2005.06.046
Ann Thorac Surg 2005;80:e22–5
HOW TO DO IT BISLERI AND MUNERETTO MINIMALLY INVASIVE AF SURGERY
e23
Fig 2. (A) The percutaneous transluminal coronary angioplasty (PTCA) catheter is inserted through the inferior port and advanced into the transverse sinus through the opened pericardial reflection between the superior vena cava and the right superior pulmonary vein. (B) Once the PTCA catheter has been advanced, it is usually visible over the surface of the right ventricle and the right atrium. (RAA ⫽ right atrial appendage; SVC ⫽ superior vena cavae.)
Fig 1. The camera port is placed in the fourth intercostals space, at the apex of the triangle and over the anterior axillary line. The instruments ports are placed in the third and fifth intercostals spaces, outside the triangle connecting the camera port, the jugular notch and the xyphoid. Continuous lines depict the connections between the camera port and the jugular notch and the xiphoid, respectively. (Dotted line ⫽ the anterior axillary line.)
positioning can be clearly assessed by advancing the endoscopic camera inside the chest through the fourth intercostal space port. First the camera scope enters the transverse sinus through the pericardial opening between the right superior pulmonary vein and the supe-
rior vena cava in order to rule out any possible malpositioning over the LAA. Then the scope is slightly retrieved and finally advanced again over the right ventricle and the apex of the heart in order to exclude any looping of the PTCA catheter over it. The tip of the Flex 10 ablation probe (Guidant, Fresno, CA) is then connected to the tail of the PTCA catheter, and the tip of the catheter is pulled out from the chest, thus allowing the positioning of the ablative device all around the four pulmonary veins. During positioning of the Flex 10 (Guidant), it is important to ensure that the black markers (ie, the nonactive side of the probe) are facing toward the patient’s head as this will orient the ablation side correctly toward the dome of the left atrium. Finally, any possible twisting of the ablation probe should be excluded when the presence of the black markers can be assessed in three specific points: (1) at the entrance of the transverse sinus, (2) at the entrance of the
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HOW TO DO IT BISLERI AND MUNERETTO MINIMALLY INVASIVE AF SURGERY
Ann Thorac Surg 2005;80:e22–5
AF. The mean age of these patients was 68.1 years (range, 53 to 81 years); the mean number of preoperative cardioversions were 1.5 (range, 0 to 3); the mean AF duration was 58.3 ⫾ 45.8 months; and the mean antero-posterior left atrial dimension was 46.8 ⫾ 4.7 mm. No conversion was required from the monolateral to the conventional bilateral approach. Mean procedural duration was 2.1 ⫾ 0.7 hours. A 28-French chest tube was placed in the right pleural space through the most inferior port. At the end of the procedure, all patients were extubated in the operating room and went back to the ward, without any postoperative stay in the intensive care unit. The postoperative course was uneventful in all cases, and the postoperative stay was 4 ⫾ 0.6 days. At a mean follow-up of 118 ⫾ 35 days, 5 patients (83.3%) were in sinus rhythm, and electrical cardioversion is pending for 1 patient.
Comment
Fig 3. (A) The tip of the percutaneous transluminal coronary angioplasty (PTCA) catheter is grasped into the oblique sinus and pulled out through the pericardial opening between the inferior vena cava (IVC) and right inferior pulmonary vein. (B) The position of the Flex 10 (Guidant, Fresno, CA) ablation probe can be safely assessed, especially with respect to the left atrial appendage. (LA ⫽ left atrium; LAA ⫽ left atrial appendage; RV ⫽ right ventricle.)
oblique sinus, and (3) at the level of the left atrial appendage. Then there is no possibility for the Flex 10 (Guidant) to present such a twisting that would cause an accidental ablation of the surrounding structures. As depicted in Figure 3B, the probe can be clearly visualized both in terms of position with respect to the LAA (ie, behind the LAA in order to avoid any damage to the circumflex artery) and with respect to orientation. Therefore the positioning and orientation of the Flex 10 (Guidant) can be performed safely even with a monolateral approach. The ablation is carried out using the Flex 10 (Guidant), setting the power at 65 Watts and performing segmental ablation of 90 seconds each, as previously reported [5]. We have performed this procedure on 6 patients to date. Three of these patients (50%) had paroxysmal AF, whereas the remaining 3 patients (50%) had permanent
Despite the tremendous efficacy of the Cox-Maze procedure [1], its diffusion has been mainly hampered by the technical complexity and surgical invasiveness that made this operation unlikely to be accepted by many patients and which was also supported by few cardiologists. Recently, we and other authors reported the feasibility of a closed-chest approach for surgical treatment of AF as a stand-alone procedure. [4] Therefore we sought to investigate the feasibility of a novel monolateral approach for thoracoscopic AF surgery in order to further improve the minimalinvasiveness of closed-chest arrhythmia surgery. Despite using nondedicated instruments, such as PTCA catheters, this innovative approach allows an effective positioning of the microwave surgical ablation probe around the four pulmonary veins; in particular, the orientation of the probe and its position with respect to the LAA can be clearly assessed, thus allowing a safe endoscopic epicardial ablation. In addition, in our experience, the bilateral approach previously described [2– 4] holds some potential drawbacks, especially in relation to the bilateral opening of the pleural space and impaired blood gas exchange when switching from the right to the left side (due to a prolonged right lung atelectasia and single left lung ventilation). Conversely, our novel monolateral, right-sided only approach allows an additional improvement in terms of minimal invasiveness by reducing the potential risk of gas exchange problems during single lung ventilation. A limitation of this procedure is of course the possibility to exclude the LAA thoracoscopically, at least with the current available tools. Removal of the LAA is commonly advocated in the original Cox-Maze procedure and accounts for the extremely low incidence of cerebrovascular accidents after the operation (0% to 1%) [6]. Nevertheless, removal of the LAA may result in undesirable physiologic sequelae (ie, reduced atrial compliance and capacity for atrial natriuretic factor secretion in response to pressure and volume overload) [7]. Recently, Gillinov and colleagues reported on a series of 500 patients that
Ann Thorac Surg 2005;80:e22–5
the presence of tears caused by the LAA stapling required additional sutures in 10% of patients, despite using less traumatic devices as buttressed staplers [8]. Finally, growing evidence from electrophysiological, clinical experiences is progressively demonstrating that the incidence of thromboembolic events is low in patients undergoing left-sided ablations for AF despite the LAA not being excluded [9, 10]. As a consequence, we share the same concerns previously raised by other authors with respect to the potential bleeding risks during thoracoscopic LAA stapling [11]; it may be foreseen that exclusion of the LAA should be performed in selected cases at higher risk, as in the presence of the previous history of cerebrovascular accidents, the presence of thrombi in the LAA, severe left atrial enlargement, left ventricular dysfunction, coagulative disorders, and high levels of hematocrit. To date, no assessment of the ablation has been performed intraoperatively. Nevertheless we believe that a real-time evaluation of the surgical ablation would dramatically improve the results of total endoscopic AF surgery, and therefore we are planning, together with our electrophysiologists, a collaboration to perform intraoperative assessment of the surgical ablation. In conclusion, despite a wider experience and further technical improvements (especially in terms of dedicated steerable catheters for encircling the pulmonary veins), we believe that our novel monolateral approach represents an important advancement in the
HOW TO DO IT BISLERI AND MUNERETTO MINIMALLY INVASIVE AF SURGERY
e25
development of a less invasive closed-chest surgical treatment of AF.
References 1. Cox JL, Schuessler RB, Cain ME, et al. Surgery for atrial fibrillation. Semin Thorac Cardiovasc Surg 1989;1:67–73. 2. Argenziano M, Williams MR. Robotic atrial septal defect repair and endoscopic treatment of atrial fibrillation. Semin Thorac Cardiovasc Surg 2003;15:130 – 40. 3. Saltman AE, Rosenthal LS, Francalancia NA, Lahey SJ. A completely endoscopic approach to microwave ablation for atrial fibrillation. Heart Surg Forum 2003;6:38 – 41. 4. Bisleri G, Manzato A, Argenziano M, Vigilance DW, Muneretto C. Thoracoscopic epicardial pulmonary vein ablation for lone paroxysmal atrial fibrillation. Europace 2005;7: 145– 8. 5. Williams MR, Knaut M, Berube D, Oz MC. Application of microwave energy in cardiac tissue ablation: from in vitro analyses to clinical use. Ann Thorac Surg 2002;74:1500 –5. 6. Cox JL, Ad N, Palazzo T. Impact of the Maze procedure on the stroke rate in patients with atrial fibrillation. J Thorac Cardiovasc Surg 1999;118:838 – 40. 7. Stollberger C, Schneider B, Finsterer J. Elimination of the left atrial appendage to prevent stroke or embolism? Chest 2003; 124:2356 – 62. 8. Gillinov AM, Pettersson G, Cosgrove DM. Stapled excision of the left atrial appendage. J Thorac Cardiovasc Surg 2005; 129:679 – 80. 9. Pappone C, Rosanio S, Augello G, et al. Mortality, morbidity, and quality of life after circumferential pulmonary vein ablation for atrial fibrillation. J Am Coll Cardiol 2003;42:185–97. 10. Wong T, Markides V, Peters NS, Davies DW. Percutaneous pulmonary vein cryoablation to treat atrial fibrillation. J Interv Card Electrophysiol 2004;11:117–26. 11. Lindsay BD. Obliteration of the left atrial appendage: a concept worth testing. Ann Thorac Surg 1996;61:515.
Surgical treatment of atrial fibrillation recently gained new popularity since the introduction of different energy sources as an alternative to the original cut-and-sew technique. Recently an innovative approach for closedchest thoracoscopic epicardial pulmonary veins isolation has been described for patients suffering from lone atrial
fibrillation. Nevertheless in an effort to further reduce the invasiveness of closed-chest atrial fibrillation surgery, we developed a novel monolateral approach for thoracoscopic arrhythmia surgery. (Ann Thorac Surg 2005;80:e22–5) © 2005 by The Society of Thoracic Surgeons
S
space on the anterior axillary line, whereas the two other instrument ports are slightly anterior, on the third and fifth intercostal spaces, outside the triangle connecting the camera port, the jugular notch, and the xiphoid. We conventionally use a 0° 10-mm scope (Karl Storlz, Tuttlingen, Germany) as the endoscopic camera. Similarly, marking of the same intercostal spaces on the left thorax is carried out in case a conversion to the bilateral approach should occur. The patient is then positioned approximately 30° toward the left decubitus. After right lung deflation, three 10-mm ports (Ethicon Endo-Surgery, Cincinnati, OH) are placed on the right hemithorax, CO2 insufflation is started (intrathoracic pressure, 10 to 12 mm Hg), and the pericardium is longitudinally opened 1 to 2 cm above the phrenic nerve. First, a wide dissection between the superior vena cava, and the right superior pulmonary vein is carried out by means of an endopeanut blunt dissector (US Surgical, Norwalk, CT); then the pericardial reflection between the inferior vena cava and the right inferior pulmonary vein is also dissected in a similar fashion. An 8-French catheter conventionally used for percutaneous transluminal coronary angioplasty (PTCA) procedures (model JR 4.0 [Guidant, Santa Clara, CA]) is then introduced through the inferior port and advanced into the transverse sinus through the pericardial opening between the superior vena cava and the right superior pulmonary vein (Fig 2A). Typically, the PTCA catheter is visible over the surface of the right ventricle and up to the right atrium (Fig 2B). The tip of the PTCA catheter is then grasped and advanced into the oblique sinus along the surface of the diaphragm. Once the tip of the catheter is visualized through the pericardial opening between the inferior vena cava and the right inferior pulmonary vein, it can be retrieved and pulled out from the chest (Fig 3A). Catheter
ince its introduction in 1989 by Cox and colleagues [1], surgical treatment of atrial fibrillation (AF) experienced a new dawn during the past few years, mainly thanks to the use of various energy sources and lesion sets that simplified the complex original maze technique. However in the majority of cases the cure of AF was associated with surgical treatment of concomitant structural cardiac diseases (ie, mitral or aortic valve or coronary disease) and was approached through a conventional sternotomy. Recently different authors described an innovative technique for closed-chest thoracoscopic epicardial pulmonary vein isolation for patients suffering from lone AF [2– 4]. Nevertheless in an effort to further reduce the invasiveness of closed-chest AF surgery, we developed a novel monolateral approach for thoracoscopic arrhythmia surgery. The main goal of the procedure lies in the possibility to effectively and safely position a microwave ablation probe around the four pulmonary veins as in the conventional bilateral approach, although only the right chest is entered.
Technique After anesthetic sedation, the patient is intubated with a double-lumen endotracheal tube for selective lung ventilation. Transesophageal echocardiography is routinely performed in order to rule out the presence of thrombi in the left atrial appendage (LAA). The patient is placed in the supine position with a square pad placed behind the back at the scapular level, with the arms along both sides of the body. Draping is then carried out in standard fashion as for a conventional bilateral thoracoscopic case. The third, fourth, and fifth intercostal spaces of the right thorax are marked for port positioning as depicted in Figure 1; briefly the camera port is positioned at the level of the fourth intercostal Accepted for publication June 3, 2005. Address correspondence to Dr Bisleri, UDA Cardiochirurgia–Spedali Civili, P.le Spedali Civili, 1, Brescia, 25123 Italy; e-mail: gianluigi_bisleri@ katamail.com.
© 2005 by The Society of Thoracic Surgeons Published by Elsevier Inc
Drs Bisleri and Muneretto disclose that they have a financial relationship with Guidant.
0003-4975/05/$30.00 doi:10.1016/j.athoracsur.2005.06.046
Ann Thorac Surg 2005;80:e22–5
HOW TO DO IT BISLERI AND MUNERETTO MINIMALLY INVASIVE AF SURGERY
e23
Fig 2. (A) The percutaneous transluminal coronary angioplasty (PTCA) catheter is inserted through the inferior port and advanced into the transverse sinus through the opened pericardial reflection between the superior vena cava and the right superior pulmonary vein. (B) Once the PTCA catheter has been advanced, it is usually visible over the surface of the right ventricle and the right atrium. (RAA ⫽ right atrial appendage; SVC ⫽ superior vena cavae.)
Fig 1. The camera port is placed in the fourth intercostals space, at the apex of the triangle and over the anterior axillary line. The instruments ports are placed in the third and fifth intercostals spaces, outside the triangle connecting the camera port, the jugular notch and the xyphoid. Continuous lines depict the connections between the camera port and the jugular notch and the xiphoid, respectively. (Dotted line ⫽ the anterior axillary line.)
positioning can be clearly assessed by advancing the endoscopic camera inside the chest through the fourth intercostal space port. First the camera scope enters the transverse sinus through the pericardial opening between the right superior pulmonary vein and the supe-
rior vena cava in order to rule out any possible malpositioning over the LAA. Then the scope is slightly retrieved and finally advanced again over the right ventricle and the apex of the heart in order to exclude any looping of the PTCA catheter over it. The tip of the Flex 10 ablation probe (Guidant, Fresno, CA) is then connected to the tail of the PTCA catheter, and the tip of the catheter is pulled out from the chest, thus allowing the positioning of the ablative device all around the four pulmonary veins. During positioning of the Flex 10 (Guidant), it is important to ensure that the black markers (ie, the nonactive side of the probe) are facing toward the patient’s head as this will orient the ablation side correctly toward the dome of the left atrium. Finally, any possible twisting of the ablation probe should be excluded when the presence of the black markers can be assessed in three specific points: (1) at the entrance of the transverse sinus, (2) at the entrance of the
e24
HOW TO DO IT BISLERI AND MUNERETTO MINIMALLY INVASIVE AF SURGERY
Ann Thorac Surg 2005;80:e22–5
AF. The mean age of these patients was 68.1 years (range, 53 to 81 years); the mean number of preoperative cardioversions were 1.5 (range, 0 to 3); the mean AF duration was 58.3 ⫾ 45.8 months; and the mean antero-posterior left atrial dimension was 46.8 ⫾ 4.7 mm. No conversion was required from the monolateral to the conventional bilateral approach. Mean procedural duration was 2.1 ⫾ 0.7 hours. A 28-French chest tube was placed in the right pleural space through the most inferior port. At the end of the procedure, all patients were extubated in the operating room and went back to the ward, without any postoperative stay in the intensive care unit. The postoperative course was uneventful in all cases, and the postoperative stay was 4 ⫾ 0.6 days. At a mean follow-up of 118 ⫾ 35 days, 5 patients (83.3%) were in sinus rhythm, and electrical cardioversion is pending for 1 patient.
Comment
Fig 3. (A) The tip of the percutaneous transluminal coronary angioplasty (PTCA) catheter is grasped into the oblique sinus and pulled out through the pericardial opening between the inferior vena cava (IVC) and right inferior pulmonary vein. (B) The position of the Flex 10 (Guidant, Fresno, CA) ablation probe can be safely assessed, especially with respect to the left atrial appendage. (LA ⫽ left atrium; LAA ⫽ left atrial appendage; RV ⫽ right ventricle.)
oblique sinus, and (3) at the level of the left atrial appendage. Then there is no possibility for the Flex 10 (Guidant) to present such a twisting that would cause an accidental ablation of the surrounding structures. As depicted in Figure 3B, the probe can be clearly visualized both in terms of position with respect to the LAA (ie, behind the LAA in order to avoid any damage to the circumflex artery) and with respect to orientation. Therefore the positioning and orientation of the Flex 10 (Guidant) can be performed safely even with a monolateral approach. The ablation is carried out using the Flex 10 (Guidant), setting the power at 65 Watts and performing segmental ablation of 90 seconds each, as previously reported [5]. We have performed this procedure on 6 patients to date. Three of these patients (50%) had paroxysmal AF, whereas the remaining 3 patients (50%) had permanent
Despite the tremendous efficacy of the Cox-Maze procedure [1], its diffusion has been mainly hampered by the technical complexity and surgical invasiveness that made this operation unlikely to be accepted by many patients and which was also supported by few cardiologists. Recently, we and other authors reported the feasibility of a closed-chest approach for surgical treatment of AF as a stand-alone procedure. [4] Therefore we sought to investigate the feasibility of a novel monolateral approach for thoracoscopic AF surgery in order to further improve the minimalinvasiveness of closed-chest arrhythmia surgery. Despite using nondedicated instruments, such as PTCA catheters, this innovative approach allows an effective positioning of the microwave surgical ablation probe around the four pulmonary veins; in particular, the orientation of the probe and its position with respect to the LAA can be clearly assessed, thus allowing a safe endoscopic epicardial ablation. In addition, in our experience, the bilateral approach previously described [2– 4] holds some potential drawbacks, especially in relation to the bilateral opening of the pleural space and impaired blood gas exchange when switching from the right to the left side (due to a prolonged right lung atelectasia and single left lung ventilation). Conversely, our novel monolateral, right-sided only approach allows an additional improvement in terms of minimal invasiveness by reducing the potential risk of gas exchange problems during single lung ventilation. A limitation of this procedure is of course the possibility to exclude the LAA thoracoscopically, at least with the current available tools. Removal of the LAA is commonly advocated in the original Cox-Maze procedure and accounts for the extremely low incidence of cerebrovascular accidents after the operation (0% to 1%) [6]. Nevertheless, removal of the LAA may result in undesirable physiologic sequelae (ie, reduced atrial compliance and capacity for atrial natriuretic factor secretion in response to pressure and volume overload) [7]. Recently, Gillinov and colleagues reported on a series of 500 patients that
Ann Thorac Surg 2005;80:e22–5
the presence of tears caused by the LAA stapling required additional sutures in 10% of patients, despite using less traumatic devices as buttressed staplers [8]. Finally, growing evidence from electrophysiological, clinical experiences is progressively demonstrating that the incidence of thromboembolic events is low in patients undergoing left-sided ablations for AF despite the LAA not being excluded [9, 10]. As a consequence, we share the same concerns previously raised by other authors with respect to the potential bleeding risks during thoracoscopic LAA stapling [11]; it may be foreseen that exclusion of the LAA should be performed in selected cases at higher risk, as in the presence of the previous history of cerebrovascular accidents, the presence of thrombi in the LAA, severe left atrial enlargement, left ventricular dysfunction, coagulative disorders, and high levels of hematocrit. To date, no assessment of the ablation has been performed intraoperatively. Nevertheless we believe that a real-time evaluation of the surgical ablation would dramatically improve the results of total endoscopic AF surgery, and therefore we are planning, together with our electrophysiologists, a collaboration to perform intraoperative assessment of the surgical ablation. In conclusion, despite a wider experience and further technical improvements (especially in terms of dedicated steerable catheters for encircling the pulmonary veins), we believe that our novel monolateral approach represents an important advancement in the
HOW TO DO IT BISLERI AND MUNERETTO MINIMALLY INVASIVE AF SURGERY
e25
development of a less invasive closed-chest surgical treatment of AF.
References 1. Cox JL, Schuessler RB, Cain ME, et al. Surgery for atrial fibrillation. Semin Thorac Cardiovasc Surg 1989;1:67–73. 2. Argenziano M, Williams MR. Robotic atrial septal defect repair and endoscopic treatment of atrial fibrillation. Semin Thorac Cardiovasc Surg 2003;15:130 – 40. 3. Saltman AE, Rosenthal LS, Francalancia NA, Lahey SJ. A completely endoscopic approach to microwave ablation for atrial fibrillation. Heart Surg Forum 2003;6:38 – 41. 4. Bisleri G, Manzato A, Argenziano M, Vigilance DW, Muneretto C. Thoracoscopic epicardial pulmonary vein ablation for lone paroxysmal atrial fibrillation. Europace 2005;7: 145– 8. 5. Williams MR, Knaut M, Berube D, Oz MC. Application of microwave energy in cardiac tissue ablation: from in vitro analyses to clinical use. Ann Thorac Surg 2002;74:1500 –5. 6. Cox JL, Ad N, Palazzo T. Impact of the Maze procedure on the stroke rate in patients with atrial fibrillation. J Thorac Cardiovasc Surg 1999;118:838 – 40. 7. Stollberger C, Schneider B, Finsterer J. Elimination of the left atrial appendage to prevent stroke or embolism? Chest 2003; 124:2356 – 62. 8. Gillinov AM, Pettersson G, Cosgrove DM. Stapled excision of the left atrial appendage. J Thorac Cardiovasc Surg 2005; 129:679 – 80. 9. Pappone C, Rosanio S, Augello G, et al. Mortality, morbidity, and quality of life after circumferential pulmonary vein ablation for atrial fibrillation. J Am Coll Cardiol 2003;42:185–97. 10. Wong T, Markides V, Peters NS, Davies DW. Percutaneous pulmonary vein cryoablation to treat atrial fibrillation. J Interv Card Electrophysiol 2004;11:117–26. 11. Lindsay BD. Obliteration of the left atrial appendage: a concept worth testing. Ann Thorac Surg 1996;61:515.