~~ ~~ ~ ~ Partial Sternotomy for Mitral Valve Operations

Delos M. Cosgrove and A. Marc Gillinov

Full median sternotomy has been the standard surgical sinoatrial node. Recent experience shows that there are approach to the for more than 30 years. There few long-term sequelae associated with this particular has been little impetus for cardiac surgeons to use incision. 8~13~15 different incisions because median sternotomy is easily Our initial minimally invasive approach to the mitral performed and provides excellent exposure of the was achieved via a 10-cm right-parasternal inci- and great vessels. With the recent development of sion and transseptal exposure of the mitral valve.’ This laparoscopic cholecystectomy and other minimally inva- incision afforded good exposure and allowed either sive surgical techniques, cardiac surgeons can now valve repair or replacement. The conversion rate to pursue other, potentially less-invasive surgical ap- median sternotomy was less than 5%, and the lengths of proaches to the heart. stay in the surgical intensive care unit and hospital were Recently there have been several reports describing significantly reduce. The primary disadvantages associ- less invasive incisions for cardiac valve . 1-8 Most ated with this technique were cannulation of the femo- of these approaches use either a partial sternotomy or a ral vessels and chest wall instability in some patients. thoracotomy. Potential advantages of these incisions Our approach to the mitral valve via a minimally include cosmetic appeal, decreased pain, decreased invasive incision has subsequently been modified. An bleeding and infection, shorter intensive care unit and 8-cm skin incision extends from the sternal angle to the hospital stays, and reduced cost. However, reduction in fourth intercostal space. The sternum is divided from the size of the operative field increases the technical the sternal notch to the fourth intercostal space, and demands of cardiac surgical procedures.* Adequate the is opened slightly to the patient’s right exposure is essential to successful operative technique, and tacked to the drapes. This provides the surgeon a and less invasive approaches to the heart cannot compro- familiar operative field. Direct cannulation of the mise the quality of the operation. Ideally, a minimally ascending and vena cavae is possible in nearly all invasive approach for any surgical procedure must instances. The use of vacuum-assisted venous drainage provide adequate exposure. allows the use of smaller, less obstructive cannulae, The mitral valve has been approached through a wide reduces the priming volume of the cardiopulmonary variety of chest wall incisions. Lillehei et a19 were the bypass circuit, and keeps the field dry. Deairing via the first to use to repair a mitral aortic root is assisted with transesophageal echocardiog- lesion. They exposed the valve through a right thora- raphy. cotomy and an incision in the left posterior to Nearly all patients with isolated mitral valve pathol- the interatrial groove. Subsequent chest wall incisions ogy are candidates for this approach. Current contrain- for mitral valve surgery have included left thoracotomy, dications include severe pectus excavatum, reopera- median sternotomy, transverse sternotomy, parasternal tion, and history of pericarditis. The appeal of this incision, and video-assisted thoracotomy. lo Similarly, a minimally invasive procedure to surgeons is that it multitude of cardiac incisions have been used to gain requires modification of a technique that they already access to the mitral ~a1ve.ll-l~Controversy surrounds know, and therefore reduces if not eliminates the steep the use of an incision over the dome of the left atrium learning curve associated with an entirely new ap- because this approach sacrifices the artery to the proach.

62 Operative Techniques in Cardiac & Thoracic Surgery, V013, NO 1 (February), 1998: pp 62-72 MINIMALLY INVASIVE MITRAL SURGERY 63

SURGICAL TECHNIQUE

1 The patient is positioned supine on the operating room table with both arms tucked. Standard monitoring lines, including a Swan-Ganz catheter if indicated, are placed. The patient is induced with standard techniques and intubated with a single lumen endotracheal tube. A transesophageal echo cardiographic probe is placed. (A) An 8-cm skin incision is made from the sternal angle to the fourth intercostal space. The soft tissue is dissected with electrocautery, and a flap is raised to allow access to the sternal notch. The sternum is opened from the sternal notch to the fourth intercostal space. (B) The sternal incision is “T-ed” off into the right-fourth intercostal space. Care is taken not to damage the right internal mammary artery or vein. 64 COSGROVE AND GILLINOV

2 A small two-bladed retractor is placed in the wound and opened. The thymic tissue is divided in the midline and ligated. The anterior pericar- dium is opened slightly to the patient’s right and tacked to the drapes with stay sutures. This elevates the heart anteriorly and affords a good view of the aorta, superior vena cava, and right atrial appendage. (On behalf of the Department of Thoracic and Cardiovascular Surgery, The Cleveland Clinic Foundation, Cleveland, OH, permission is granted to reproduce Figs 2-13.)

3 After heparinization, the aorta is cannulated with a 20F Sarns soft-flow cannula (Sarns 3-M Healthcare, Ann Arbor, MI). A 22F right angle cannula is placed in the superior vena cava, and a second 22F right-angle cannula is placed through the posterior portion of the right atrial appendage into the inferior vena cava. A cardioplegia catheter is placed in the aortic root. The cardiopulmonary bypass is initiated with active negative pressure on the venous lines (-50 cm H,O), and the heart decompressed. The aorta is cross-clamped, and antegrade cardioplegia is administered. Snares pre- viously placed around the inferior and superior vena cavae are tightened. The planned incision in the right atrium is indicated. MINIMALLY INVASIVE MITRAL SURGERY 65

4 The right atrial incision is started at the right-atrial appendage, and extended cepha- lad toward the dome of the left atrium and caudad, toward the inferior vena cava. Stay sutures are placed on the right-atrial wall to aid exposure. A cannula is placed in the coronary sinus for delivery of retrograde cardioplegia. The planned incision in the interatrial septum is indicated.

5 The septum is opened through the fossa ovalis, and the incision is ex- tended superiorly onto the dome of the left atrium. Pledgetted stay sutures are placed through the superior portion of the septum and retracted toward the patient’s left. 66 COSGROVE AND GILLINOV

6 Two hand-held retractors are placed at the superior and inferior portions of the left atrium. Additionally, a “sweetheart” retractor is placed along the posterior aspect of the septa1 incision to rotate the mitral valve into view. A flail portion of the posterior leaflet of the mitral valve is identified and excised. MINIMALLY INVASIVE MITRAL SURGERY 67

7 Transseptal exposure of the mitral valve: (A) the interatrial septum is incised, and (B) hand-held retractors placed along the anterior portion of the incision. (C) An additional retractor placed at the posterior aspect of the incision rotates the mitral valve into view. 68 COSGROVE AND GlLLINOV

8 The flail portion of the posterior leaflet is resected, and the leaflet edges reapproximated with a running 5-0 mul- tifilament suture. One or two pledgetted sutures are used to reapproximate the annulus in the region of leaflet repair.

9 After completion of repair of the valve mechanism, an annuloplasty is performed. Horizontal mattress sutures of multifilament 2-0 are placed begin- ning at the fibrous trigone, and proceed- ing around the posterior annulus to the opposite fibrous trigone. Sutures are then passed through the Cosgrove- Edwards annuloplasty band (Baxter Healthcare Corp, Irvine, CA) at regular intervals. MINIMALLY INVASIVE MITRAL SURGERY 69

10 The handle is released, and the annuloplasty band slid into position.

11 Sutures are tied and the stent is removed, leaving the annuloplasty band in place. 70 COSGROVE AND GILLINOV

12 The incision in the left atrium is closed, using continuous 4-0prolene sutures. Before closure of the incision in the interatrial septum, air is evacuated from the left atrium. The retrograde car- dioplegia cannula is removed be- fore closure of the right atrium. Deairing of the left is facili- tated by gentle suction on the car- dioplegia cannula in the ascending aorta before and after removal of the aortic crossclamp. Deairing is guided by transesophageal echocar- diography.

13 The incision in the right atrium is closed, and the aortic crossclamp is removed. After normal cardiac function has returned, the can- nulae are removed. Four pacemaker wires are placed. MINIMALLY INVASIVE MITRAL SURGERY 71

14 Two 28F chest tubes are placed, one in the right pleural space and one in the mediastinum. The wound is closed in layers. The skin incision is 8-cm long, extending from the sternal angle to the fourth intercostal space. 72 COSGROVE AND GILLINOV

COMMENTS affords the surgeon a familiar operative field from From March 1997 to August 1997, the mini-sternotomy which either or replacement are possible. In most cases, femoral cannulation is avoided. was used to perform mitral valve surgery in 89 patients. Benefits to the patient include a smaller incision, Mean patient age was 54.6 ? 13.3 years; 58 patients reduced pain and bleeding, low incidence of wound were men. Seventy-one percent of patients were New complications, and short intensive care unit and hospi- York Heart Association Functional Class I or 11, and 94% had normal or mildly impaired left ventricular tal stays. Finally, preliminary analysis shows that function. Indications for surgery were mitral regurgita- minimally invasive mitral valve surgery results in re- tion in 74 patients, mitral stenosis in 2 patients, and duced hospital cost.8 mixed lesions in 13 patients. REFERENCES Cannulation for bypass was accomplished centrally in the chest in most patients. Arterial cannulation was 1. Navia JL, Cosgrove DM: Minimally iuvasive mitral valve operations. done via the aorta in 84 patients (94%), and via the Ann Thorac Surg 62:1542-1544, 1996 2. Benetti FJ, Rizzartli JL, Pire L, et al: Mitral under femoral artery in 5 patients (6%). Venous cannulation video assistance through a minithoracotomy. Ann Thorac Surg 63:1150- was done via the superior and inferior vena cavae in 88 1152,1997 patients (99%) and via the superior vena cava and 3. Chitwood WR, Elbeery JR, Moran JF, et al: Minimally invasive mitral valve repair using transthoracic aortic occlusion. Ann Thorac Surg femoral vein in 1 patient (1%). Seventy-four patients 63:1477-1479,1997 had mitral valve repair and 15 had mitral valve 4. Chitwood WR, Elbeery JR, Chapman WHH, et al: Video-assisted replacement. Associated procedures included tricuspid minimally invasive mitral valve surgery: The micro-mitral operation. J valve repair in 7 patients, and coronary artery bypass Thorac Cardiovasc Surg 113:413414,1997 5. Schwartz DS, Ribakove G, Grossi EA, et al: Minimally invasive mitral grafting (saphenous vein graft to the right coronary valve replacement: Port-access technique, feasibility, and myocardial artery) in 1 patient. Four patients required conversion functional preservation. J Thorac Cardiovasc Surg 113:1022-1031,1997 to complete sternotomy because of inadequate expo- 6. Pompili MF, Stevens JH, Burdon TA, et al: Port-access in dogs. J Thorac Cardiovasc Surg 112:1268-1274, 1996 sure; 2 of these patients had chest wall deformities, 7. Cosgove DM, Sabik JF: Minimally invasive approach for aortic valve including pectus excavatum in one. Mean aortic cross- operations. Ann Thorac Surg 62:596-597, 1996 clamp time was 61.6 5 17.8 minutes, and mean cardio- 8. Cosgrove DM, Sabik JF, Navia J: Minimally invasive valve surgery. Ann Thorac Surg (in press) pulmonary bypass time was 78.7 ? 18.6 minutes. For 9. LiIlehei CW, Gott VL, DeWall RA, et al: The surgical treatment of patients undergoing mitral valve repair, mean degree stenotic or regurgitant lesions of the mitral and aortic valves by direct of mitral regurgitation decreased from 3.84 5 0.41 vision utilizing a pump-oxygenator. J Thorac Cardiovasc Surg 35: 154- prebypass, to 0.17 5 0.28 postbypass. 191, 1958 10. Balasundaram BG, Duran C: Surgical approaches to the mitral valve. J All patients remained intubated after surgery, and Card Surg 5:163-169, 1990 were taken to the intensive care unit for recovery. Mean 11. El Saegh MM, My MA, El Sayegy T, et al: Transseptal approach for time to extubation was 7.1 2 3.9 hours, with 58% of mitral valve surgery. Tex Heart Inst J 20:23-27,1993 12. Deloche A, Acar C, Jebara V, et al: Biatrial transseptal approach in case patients extubated in less than 6 hours. Sixty-one of difficult exposure to the mitral valve. Ann Thorac Surg 50:318-319, percent of patients spent less than 24 hours in the 1990 intensive care unit, and median intensive care unit 13. Guiraudon GM, Ofiesh JG, Kaushik R: Extended vertical transatrial septa1 approach to the mitral valve. Aun Thorac Surg 52:1058-1062, length of stay was 23 hours. Mean postoperative chest 1991 tube drainage was 385 t- 199 mLs, and 85% of patients 14. Kumar N, Saad I, Prabhakar G, et al: Extended transseptal versus received no blood products. Median hospital length of conventional left atriotomy: Early postoperative study. Ann Thorac stay was 6 days, with a range from 4 to 57 days. Surg 60:426-430,1995 15. Alfieri 0, Sandrelli L, Pardini A, et al: Optimal exposure of the mitral Five patients (5.6%) returned to the operating room valve through an extended vertical transseptal approach. Eur J Cardio- because of postoperative bleeding. Other postoperative thorac Surg 5294-299, 1991 complications included respiratory insufficiency (3), 16. CouetiI JPA, Ramsheyi A, Tolan MJ, et al: Biatrial inferior transseptal approach to the mitral valve. Ann Thorac Surg 60:1432-1433,1995 stroke (l),need for a permanent pacemaker (2), and 17. Utley JR, Leyland SA, Ngnyenduy T: Comparison of outcomes with wound infection requiring sternal debridement and three atrial incisions for mitral valve operations. J Thorac Cardiovasc muscle flap closure (1).Two patients had dehiscence of Surg 109:582-587,1995 18. Larbalestier RI, Chard RB, Cohn LH: Optimal approach to the mitral their mitral valve repairs; 1 patient had mitral valve valve: Dissection of the interatrial groove. Ann Thorac Surg 54:1186- replacement and 1had rerepair. There were no hospital 1188,1992 deaths. 19. Molina JE: The superior approach for mitral valve replacement. J Card These results demonstrate that mitral valve surgery Surg 3:203-213,1988 can be accomplished successfully using a mini-ster- From the Department of Thoracic and Cardiovascular Surgery, The Cleveland notomy and transseptal approach to the mitral valve. Clinic Foundation, Cleveland, OH. Inadequate exposure, necessitating conversion to full Address reprint requests to Delos M. Cosgrnve, MD, Department afThoracic and sternotomy, is infrequent. The presence of severe pec- Cardiovascular Surgery, The Cleveland Clinic Foundation (F25), 9500 Euclid Ave, Cleveland, OH 44195. tus excavatum, or other significant chest wall deformity Copyright 0 1998 by W.B. Saunders Company is a contraindication to this approach. This incision 1085-5637/98/0301-0001$8.00/0