- Email: [email protected]
Minimally invasive coronary artery bypass grafting
Minimally Invasive Coronary Artery Bypass Grafting Tea E. Acuff, MD, Rodney J. Landreneau, MD, Bartley P. Griffith, MD, a n d Michael J. Mack, MD Division of Cardiothoracic Surgery, Medical City Dallas Hospital Dallas, Texas, and Division of Cardiothoracic Surgery, University of Pittsburgh, Pittsburgh, Pennsylvania
Background. Standard options for the invasive management of proximal disease of the left anterior descending coronary artery include coronary artery bypass grafting with a left internal mammary artery and percutaneous
transluminalcoronaryansiopl~y. Methods. We describe a s~rgical technique for bypass of the left anterior descending coronary artery with a ]eft internal mammary artery without median sternotomy and without cardiopulmonary bypass. Thoracoscopy is used to harvest the internal mammary artery, whereas the mammary-coronary artery anastomosis is performed un-
ingle-vessel coronary bypass grafting using the left internal m a m m a r y artery (LIMA) to the left anterior descending coronary artery (LAD) has been extensively demonstrated to produce excellent long-term results with almost no mortality [1]. Despite these results, this procedure is not widely used for treating proximal disease of the LAD, which is instead most frequently managed by percutaneous transluminal coronary angioplasty [2]. In an attempt to make coronary artery grafting less invasive with less perioperative morbidity than conventional operation, we describe the following technique for performing bypass of the LAD with a LIMA.
S
Technique Standard cardiac operation anesthetic techniques are used including premedication with diazepam, induction with propofol and sufentanil, and maintenance with desflurane. Use of transesophageal echocardiography is helpful to monitor ventricular wall motion as well as an atrial-ventricular pacing pulmonary artery flotation catheter. A double lumen endotracheal tube is placed to facilitate thoracoscopic LIMA harvest. In addition, external defibrillation pads are placed on the patient and connected to a cardioverterldefibrillator. A perfusionist and cardiopulmonary bypass p u m p are available in the operating room. The patient is placed in a 30-degree right lateral decubitus position. The LIMA harvest is performed first. A standard 10-ram 0-degree right thoracoscope is placed through a trocar placed in the fourth intercostal space in Accepted for publication Sep 9, 1995. Address reprint requests to Dr Mack, 7777Forest Ln, Suite 323-A,Dallas, TX 75230. © 1996 by The Society of Thoracic Surgeons Published by Elsevier Science Inc
der direct vision through a limited anterior thoracotomy. Results. We have performed this procedure successfully in 3 patients with minimal morbidity and shortened hospital stay. Average operative time was 3 hours and postoperative hospital stay averaged less than 48 hours. Conclusions. Although experience is limited and follow-up is very short, with further experience, this less invasive surgical technique may become a viable option for the management of proximal left anterior descending disease.
(Ann Thorac Surg 1996;61:135-7)
the posterior axillary line (Fig 1). Additional ports are placed in the third and fifth intercostal spaces for introduction of an endoscopic grasping instrument and scissors with electrocautery. The LIMA is then harvested as a pedicle with video imaging and standard surgical technique with control of side branches by either cautery or endoscopic clips. The time required for thoracoscopic LIMA harvest is approximately 45 minutes. A limited anterior thoracotomy incision is then made over the fourth intercostal space and the cartilage portion of the fourth rib is resected (Fig 2). Curvilinear extension of the incision superiorly and medially with division of the third costal cartilage can further enhance exposure. Furthermore, the LIMA can be harvested under direct vision through this incision instead of thoracoscopically with suificient proximal mobilization for anastomosis. A vertical incision is made in the pericardium and stay sutures placed (Fig 3). Traction of these sutures will distract the heart into the incision allowing fuller visualization of the left anterior descending artery. Snare sutures of 5-0 polypropylene are placed proximally and distally from the target area on the LAD to be bypassed. The vessel is looped or tourniquets placed to occlude the vessel at the time of the anastomosis. The heart rate is slowed to approximately 40 beats/min by the administration of esmolol or diltiazem to minimize motion in the operative field. Nitroglycerin is also given to reduce ischemia and 10,000 units of heparin is administered. If the coronary artery is totally occluded proximally, occlusion of the vessel for anastomosis is well tolerated. If, however, the proximal artery is stenosed but patent, intermittent vessel occlusion to induce ischemic preconditioning may be helpful [3]. The snare sutures are test occluded intermittently over a 10-minute period and wall 0003-4975/96/$15.00 SSDI 0003-4975(95)00907-8
136
A C U F F ET A L MINIMALLY INVASIVE BYPASS
Ann Thorac Surg 1996;61:135-7
\ Fig 1. The left internal mammary artery is harvested by a left thoracoscopic approach.
motion changes are assessed by transesophageal echocardiography. During this time, the previously harvested LIMA is divided distally and the end of the m a m m a r y artery is brought through the incision and prepared for grafting. The anastomosis between LIMA and LAD is next performed using 8-0 polypropylene suture. Use of an assistant to stabilize the motion of the heart and
Fig 3. Through a pericardial window anastomosis of the left internal mammary artery to the left anterior descending coronary artery is performed under direct vision. Note stay sutures that suspend the pericardium and bring the heart into view.
constant irrigation or suction to clear the coronary artery facilitates the anastomosis. The anastomosis requires 7 to 10 minutes to complete. Upon satisfactory completion of the anastomosis, the esmolol infusion is discontinued and the pericardium is partially closed with care not to kink the LIMA and a small drain is placed inside the pericardium. Pleura and prepectoral fascia are closed to prevent lung herniation.
Results /
L_J I
\~
/
\, '~
~
i
i
JJ
(~ - _ --
i
/
/
~
t
/
j'~
~ ,,, ~'l'\4th j~ l~',J I
/
" / /
-~- / /
hv
/
rib
,~i,',
/
h~
/
r
/
Fig 2. A limited anterior thoracotomy incision (8 cm) is made over the fourth intercostal space and the fourth rib is resected. Extension of the incision superomedially ( d o t t e d l i n e ) or resection of the cartilage of the third rib may enhance exposure.
Three patients have undergone coronary artery bypass using this technique in our institutions, 2 in Dallas and 1 in Pittsburgh. The patients were all men, ages 35, 42, and 76 years, with single vessel coronary disease with subtotal or total occlusion of the LAD and medically refractory angina. One patient had restenosis after previous percutaneous transluminal coronary angioplasty and the other 2 patients were not candidates for percutaneous transluminal coronary angioplasty because of a totally occluded LAD. Cardiopulmonary bypass was not used and the procedure was well tolerated by all patients. Total operative time (initial incision to dressing) was 2 hours 30 minutes, 3 hours, and 3 hours 30 minutes. All patients were extubated in the operating room and mobilized to a chair immediately. Discharge was 36, 42, and 60 hours after operation. A postoperative angiogram of the third patient demonstrates graft patency, as shown in Figure 4. All patients are asymptomatic at 3, 4, and 5 months postoperatively.
Ann Thorac Surg 1996;61:135-7
left internal mammary artery to left anterior descending coronary artery anastomosis.
ACUFF ET AL MINIMALLY INVASIVE BYPASS
137
potential for "'steal" through patent proximal side branches exists. Therefore, we prefer the thoracoscopic approach by which complete proximal mobilization of the LIMA with ligation and division of all side branches as is performed by standard open techniques can be accomplished. It should be emphasized that this is a technique in evolution, with variations being used in many centers. Other applicable options being investigated include percutaneous femoral-femoral bypass or use of the Hem o p u m p device (dlp, a division of Medtronic, Grand Rapids, MI) for hemodynamic support. Many laboratories have been able to accomplish totally endoscopic myocardial revascularization in the animal model. Techniques of percutaneous myocardial protection by aortic balloon catheters for aortic occlusion, cardioplegia delivery, and left ventricular venting are being explored. Percutaneous retrograde cardioplegia delivery through a coronary sinus catheter has also been described. Gradual improvement in many of these techniques may simplify and extend the procedure described here. If the long term results of LIMA to LAD revascularization can be duplicated by less invasive techniques, a new surgical option for management of coronary artery disease may be possible. References
Comment Excellent results of coronary bypass using the LIMA to the LAD have been well demonstrated with 10-year patency of 85% to 95% being reported [1]. Despite these results, coronary angioplasty has become the most widely applied procedure for treatment of proximal LAD disease with restenosis rates from 33% to 60% at 6 months [2]. Although surgical mortality is less than 1%, some morbidity exists from the median sternotomy incision and use of cardiopulmonary bypass. Recent efforts in all surgical fields have focused on less invasive surgical techniques. Myocardial revascularization without extracorporeal support was discussed in 1967 by Kolessov [4]. Subsequently, it has been described by Benetti [5], Pfister [6], and Fanning [7] and their colleagues. Others have reported thoracotomy access for bypass grafting [8, 9]. The technique described in this report combines "off p u m p " bypass with a limited anterior thoracotomy and thoracoscopic LIMA harvest to accomplish myocardial revascularization in a less invasive approach than standard techniques. Although the LIMA can be harvested directly through the limited anterior thoracotomy incision without thoracoscopy, the
1. Loop FD, Lytle BW, Cosgrove DM, Stewart RW, et al. Influence of the internal mammary artery graft of 10 year survival and other cardiac events. N Engl J Med 1986;314: 1-6. 2. Landau C, Lange RA, Hillis LD. Percutaneous transluminal coronary angioplasty. N Engl J Med 1994;330:14:981-93. 3. Murry CE, Richard VJ, Reimer KA, Jennings RB. Ischemic preconditioning slows energy metabolism and delays ultrastructural damage during a sustained ischemic episode. Circ Res 199@,66:913-31. 4. Kolessov VL. Mammary artery-coronary artery anastomosis as a method of treatment for angina pectoris. J Thorac Cardiovasc Surg 1967;54;535-44. 5. Benetti F, AseUi G, Wood M, Get'her L. Direct myocardial revascularization without extracorporeal circulation. Chest 1991;100".312-6. 6. Pfister AJ, Zaki MS, Garcia JM, et al. Coronary artery bypass without cardiopulmonary bypass. Ann Thorac Surg 1992;54: 1085-92. 7. Fanning W, Kakos G, Williams T. Reoperative coronary bypass without coronary pulmonary bypass. Ann Thorac Surg 1993",55:46-9. 8. Gandjbakhch AC. Left thoracotomy approach for coronary artery bypass grafting in patients with pericardial adhesions. Ann Thorac Surg 1989, 48:871-3. 9. Uppal R, Wolfe WG, Lowe JE, Smith PK. Right thoracotomy for reoperative right coronary artery bypass procedures. Ann Thorac Surg 1994;57:123--5.
Background. Standard options for the invasive management of proximal disease of the left anterior descending coronary artery include coronary artery bypass grafting with a left internal mammary artery and percutaneous
transluminalcoronaryansiopl~y. Methods. We describe a s~rgical technique for bypass of the left anterior descending coronary artery with a ]eft internal mammary artery without median sternotomy and without cardiopulmonary bypass. Thoracoscopy is used to harvest the internal mammary artery, whereas the mammary-coronary artery anastomosis is performed un-
ingle-vessel coronary bypass grafting using the left internal m a m m a r y artery (LIMA) to the left anterior descending coronary artery (LAD) has been extensively demonstrated to produce excellent long-term results with almost no mortality [1]. Despite these results, this procedure is not widely used for treating proximal disease of the LAD, which is instead most frequently managed by percutaneous transluminal coronary angioplasty [2]. In an attempt to make coronary artery grafting less invasive with less perioperative morbidity than conventional operation, we describe the following technique for performing bypass of the LAD with a LIMA.
S
Technique Standard cardiac operation anesthetic techniques are used including premedication with diazepam, induction with propofol and sufentanil, and maintenance with desflurane. Use of transesophageal echocardiography is helpful to monitor ventricular wall motion as well as an atrial-ventricular pacing pulmonary artery flotation catheter. A double lumen endotracheal tube is placed to facilitate thoracoscopic LIMA harvest. In addition, external defibrillation pads are placed on the patient and connected to a cardioverterldefibrillator. A perfusionist and cardiopulmonary bypass p u m p are available in the operating room. The patient is placed in a 30-degree right lateral decubitus position. The LIMA harvest is performed first. A standard 10-ram 0-degree right thoracoscope is placed through a trocar placed in the fourth intercostal space in Accepted for publication Sep 9, 1995. Address reprint requests to Dr Mack, 7777Forest Ln, Suite 323-A,Dallas, TX 75230. © 1996 by The Society of Thoracic Surgeons Published by Elsevier Science Inc
der direct vision through a limited anterior thoracotomy. Results. We have performed this procedure successfully in 3 patients with minimal morbidity and shortened hospital stay. Average operative time was 3 hours and postoperative hospital stay averaged less than 48 hours. Conclusions. Although experience is limited and follow-up is very short, with further experience, this less invasive surgical technique may become a viable option for the management of proximal left anterior descending disease.
(Ann Thorac Surg 1996;61:135-7)
the posterior axillary line (Fig 1). Additional ports are placed in the third and fifth intercostal spaces for introduction of an endoscopic grasping instrument and scissors with electrocautery. The LIMA is then harvested as a pedicle with video imaging and standard surgical technique with control of side branches by either cautery or endoscopic clips. The time required for thoracoscopic LIMA harvest is approximately 45 minutes. A limited anterior thoracotomy incision is then made over the fourth intercostal space and the cartilage portion of the fourth rib is resected (Fig 2). Curvilinear extension of the incision superiorly and medially with division of the third costal cartilage can further enhance exposure. Furthermore, the LIMA can be harvested under direct vision through this incision instead of thoracoscopically with suificient proximal mobilization for anastomosis. A vertical incision is made in the pericardium and stay sutures placed (Fig 3). Traction of these sutures will distract the heart into the incision allowing fuller visualization of the left anterior descending artery. Snare sutures of 5-0 polypropylene are placed proximally and distally from the target area on the LAD to be bypassed. The vessel is looped or tourniquets placed to occlude the vessel at the time of the anastomosis. The heart rate is slowed to approximately 40 beats/min by the administration of esmolol or diltiazem to minimize motion in the operative field. Nitroglycerin is also given to reduce ischemia and 10,000 units of heparin is administered. If the coronary artery is totally occluded proximally, occlusion of the vessel for anastomosis is well tolerated. If, however, the proximal artery is stenosed but patent, intermittent vessel occlusion to induce ischemic preconditioning may be helpful [3]. The snare sutures are test occluded intermittently over a 10-minute period and wall 0003-4975/96/$15.00 SSDI 0003-4975(95)00907-8
136
A C U F F ET A L MINIMALLY INVASIVE BYPASS
Ann Thorac Surg 1996;61:135-7
\ Fig 1. The left internal mammary artery is harvested by a left thoracoscopic approach.
motion changes are assessed by transesophageal echocardiography. During this time, the previously harvested LIMA is divided distally and the end of the m a m m a r y artery is brought through the incision and prepared for grafting. The anastomosis between LIMA and LAD is next performed using 8-0 polypropylene suture. Use of an assistant to stabilize the motion of the heart and
Fig 3. Through a pericardial window anastomosis of the left internal mammary artery to the left anterior descending coronary artery is performed under direct vision. Note stay sutures that suspend the pericardium and bring the heart into view.
constant irrigation or suction to clear the coronary artery facilitates the anastomosis. The anastomosis requires 7 to 10 minutes to complete. Upon satisfactory completion of the anastomosis, the esmolol infusion is discontinued and the pericardium is partially closed with care not to kink the LIMA and a small drain is placed inside the pericardium. Pleura and prepectoral fascia are closed to prevent lung herniation.
Results /
L_J I
\~
/
\, '~
~
i
i
JJ
(~ - _ --
i
/
/
~
t
/
j'~
~ ,,, ~'l'\4th j~ l~',J I
/
" / /
-~- / /
hv
/
rib
,~i,',
/
h~
/
r
/
Fig 2. A limited anterior thoracotomy incision (8 cm) is made over the fourth intercostal space and the fourth rib is resected. Extension of the incision superomedially ( d o t t e d l i n e ) or resection of the cartilage of the third rib may enhance exposure.
Three patients have undergone coronary artery bypass using this technique in our institutions, 2 in Dallas and 1 in Pittsburgh. The patients were all men, ages 35, 42, and 76 years, with single vessel coronary disease with subtotal or total occlusion of the LAD and medically refractory angina. One patient had restenosis after previous percutaneous transluminal coronary angioplasty and the other 2 patients were not candidates for percutaneous transluminal coronary angioplasty because of a totally occluded LAD. Cardiopulmonary bypass was not used and the procedure was well tolerated by all patients. Total operative time (initial incision to dressing) was 2 hours 30 minutes, 3 hours, and 3 hours 30 minutes. All patients were extubated in the operating room and mobilized to a chair immediately. Discharge was 36, 42, and 60 hours after operation. A postoperative angiogram of the third patient demonstrates graft patency, as shown in Figure 4. All patients are asymptomatic at 3, 4, and 5 months postoperatively.
Ann Thorac Surg 1996;61:135-7
left internal mammary artery to left anterior descending coronary artery anastomosis.
ACUFF ET AL MINIMALLY INVASIVE BYPASS
137
potential for "'steal" through patent proximal side branches exists. Therefore, we prefer the thoracoscopic approach by which complete proximal mobilization of the LIMA with ligation and division of all side branches as is performed by standard open techniques can be accomplished. It should be emphasized that this is a technique in evolution, with variations being used in many centers. Other applicable options being investigated include percutaneous femoral-femoral bypass or use of the Hem o p u m p device (dlp, a division of Medtronic, Grand Rapids, MI) for hemodynamic support. Many laboratories have been able to accomplish totally endoscopic myocardial revascularization in the animal model. Techniques of percutaneous myocardial protection by aortic balloon catheters for aortic occlusion, cardioplegia delivery, and left ventricular venting are being explored. Percutaneous retrograde cardioplegia delivery through a coronary sinus catheter has also been described. Gradual improvement in many of these techniques may simplify and extend the procedure described here. If the long term results of LIMA to LAD revascularization can be duplicated by less invasive techniques, a new surgical option for management of coronary artery disease may be possible. References
Comment Excellent results of coronary bypass using the LIMA to the LAD have been well demonstrated with 10-year patency of 85% to 95% being reported [1]. Despite these results, coronary angioplasty has become the most widely applied procedure for treatment of proximal LAD disease with restenosis rates from 33% to 60% at 6 months [2]. Although surgical mortality is less than 1%, some morbidity exists from the median sternotomy incision and use of cardiopulmonary bypass. Recent efforts in all surgical fields have focused on less invasive surgical techniques. Myocardial revascularization without extracorporeal support was discussed in 1967 by Kolessov [4]. Subsequently, it has been described by Benetti [5], Pfister [6], and Fanning [7] and their colleagues. Others have reported thoracotomy access for bypass grafting [8, 9]. The technique described in this report combines "off p u m p " bypass with a limited anterior thoracotomy and thoracoscopic LIMA harvest to accomplish myocardial revascularization in a less invasive approach than standard techniques. Although the LIMA can be harvested directly through the limited anterior thoracotomy incision without thoracoscopy, the
1. Loop FD, Lytle BW, Cosgrove DM, Stewart RW, et al. Influence of the internal mammary artery graft of 10 year survival and other cardiac events. N Engl J Med 1986;314: 1-6. 2. Landau C, Lange RA, Hillis LD. Percutaneous transluminal coronary angioplasty. N Engl J Med 1994;330:14:981-93. 3. Murry CE, Richard VJ, Reimer KA, Jennings RB. Ischemic preconditioning slows energy metabolism and delays ultrastructural damage during a sustained ischemic episode. Circ Res 199@,66:913-31. 4. Kolessov VL. Mammary artery-coronary artery anastomosis as a method of treatment for angina pectoris. J Thorac Cardiovasc Surg 1967;54;535-44. 5. Benetti F, AseUi G, Wood M, Get'her L. Direct myocardial revascularization without extracorporeal circulation. Chest 1991;100".312-6. 6. Pfister AJ, Zaki MS, Garcia JM, et al. Coronary artery bypass without cardiopulmonary bypass. Ann Thorac Surg 1992;54: 1085-92. 7. Fanning W, Kakos G, Williams T. Reoperative coronary bypass without coronary pulmonary bypass. Ann Thorac Surg 1993",55:46-9. 8. Gandjbakhch AC. Left thoracotomy approach for coronary artery bypass grafting in patients with pericardial adhesions. Ann Thorac Surg 1989, 48:871-3. 9. Uppal R, Wolfe WG, Lowe JE, Smith PK. Right thoracotomy for reoperative right coronary artery bypass procedures. Ann Thorac Surg 1994;57:123--5.