British Journal of Plustic Surgery ( 1996). 49, 220-222 0 1996 The B&h Association of Plastic Surgeons

Reduction mammaplasty combined with pectoralis major muscle flaps for median sternotomy wound closure

S. de Fontaine, S. Devos and D. Goldschmidt

Plastic Surgery Department, University Hospital Erasme, Brussels, Belgium

SUMMARY. Sternal wound infection can be a problem in patients who undergo coronary artery bypass graft surgery and is usually treated with local flaps. Severe macromastia can cause a large wound dehiscence by inferolateral tension on the skin sutures. Chest wall reconstruction can be achieved by combining muscle flap coverage with reduction mammaplasty. Two musculoglandulocutaneous flaps can be designed, using two superiorly based pectoralis muscle flaps vascularising the medial portion of the glandular breast tissue. The flaps are advanced medially to the sternectomy site and the breast reduction is then completed by adjusting the lateral breast pillar to the medial breast pillar. A case in which this technique was successfully used is reported.

Sternal wound dehiscence is a recognised problem after cardiac surgery, and has been reported to occur in 0.555% of patients.’ Chest wall reconstruction after cardiac surgery is usually performed with local flaps, including the pectoralis major muscle flap, the rectus abdominis muscle flap and omentum.2 Macromastia causes significant tension on the midline skin closure and this can result in a large wound dehiscence. To prevent this, we have combined sternal wound closure with bilateral breast reductions.

Case report

A 66-year-old woman underwent a three-vessel coronary artery bypass using the left internal mammary artery and two vein grafts. On the thirteenth postoperative day, the patient developed septicemia with fluctuation at the sternal suture line. The wound opened spontaneously and a puru- lent exudate was evacuated. Blood cultures were positive for Enterococcus faecalis and Escherichia coli. The patient was given antibiotics intravenously and sterile dressings were applied. On the seventeenth day, she underwent radical debridement of the sternum, followed by chest reconstruc- tion with a superiorly based right rectus abdominis muscle flap. Large transfixion sutures were used to hold the breasts medially to prevent excessive lateral skin tension due to macromastia. The sutures were removed 3 weeks postopera- tively. The closed medial wound reopened because of excessive lateral traction of the breasts. This wound dehiscence was superficial, showing a well vascularised rectus abdominis muscle flap deep in the wound adherent to the mediastinum (Fig. 1A). Wet-to-dry dressings were applied three times daily. A new procedure was then performed to achieve two goals: to close the large midline wound dehiscence with well vascularised tissues, and to reduce inferolateral breast traction on the wound. Because of several general health problems, she had further surgery 71 days after the previous operation. Superiorly based pectoralis major muscle flaps were designed to support the medial glandular pillar of the breast in a combined chest reconstruction and reduction mammaplasty (Fig. 18). The two flaps, vascularised by the thoracoacromial pedicles

(Fig. lC), were advanced to the midline and attached to the rectus abdominis muscle flap. Adjustment of the exter- nal glandular pillars of the breasts was then performed using a conventional amputative reduction mammaplasty technique according to Thorek.3 Successful healing of the wound was achieved (Fig. 1D).

Discussion

The weight of large breasts produces an important inferolateral tension on a vertical sternotomy incision and this can lead to sternal wound dehiscence. The treatment of sternomediastinitis in a patient with severe macromastia should thus combine the treat- ment of sternomediastinitis with the treatment of the macromastia. A combined procedure, using two pec- toralis muscle flaps to reconstruct the sternectomy site followed by a reduction mammaplasty, has been proposed for treating sternomediastinitis in patients with macromastia.4 In this technique, two superiorly based pectoralis muscle flaps are plicated in an over- lapping fashion on the midline after radical debride- ment of the sternum. Skin flaps, previously elevated 6 cm from the midline, are then sutured to close the midline wound. Finally, an amputative breast reduction is performed. Elevation of skin flaps 6 cm from the midline leads to division of the branches of the internal mammary artery perforators which run from the pectoralis major muscle and vascularise the medial part of the breast, with the potential risk of necrosis of this part of the breast in the subsequent amputative breast reduction.

The pectoralis major muscle is a type V muscle flap, according to the classification of the vascular anatomy of muscles of Mathes and Nahai.’ This muscle has one dominant vascular pedicle, the thora- coacromial vessels, and multiple secondary segmental vascular pedicles, branches of the internal mammary vessels, which pass through the muscle on their way to the overlying breast tissue and skin. The blood

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Reduction mammaplasty combined with pectoralis major muscle flaps 221

Fig. 1

Figure l-(A) Inferior dehiscence of sternal wound. (B) Preoperative drawing of the amputative breast reduction and bilateral pectoralis major muscle flaps advancement. (C) Peroperative view showing the sternal wound reopened (upper arrow), the composite flap consisting of the medial pillar of the left breast with the underlying pectoralis major muscle (middle arrow), and the site of division of the pectoralis major tendon (lower arrow). (D) Postoperative view. 3 months after the last procedure.

supply of the breast is derived, in its upper and medial parts, from medial perforating branches of the internal mammary artery.6 The vascular pedicles of the pectoralis major muscle anastomose extensively within the muscle so the dominant thoracoacromial pedicle can supply the medial breast tissue and skin originally supplied by the branches of the internal mammary vessels. A large composite musculoglandul- ocutaneous flap, based on the thoracoacromial vessels superiorly, of the pectoralis major muscle with the overlying medial portion of the breast can thus be elevated and advanced medially (Fig. 2). The ana- tomical basis of this musculoglandulocutaneous flap is the vascular connections within the muscle between the thoracoacromial axis network and the internal mammary vessel network, which in turn connect with w v the overlying breast tissue. The pectoralis major muscle, used for covering the superior sternectomy Fig. 2

site, will also provide the blood supply to the overly- Figure 2--Schematic drawing showing the right thoracoacromial

ing breast tissue that will become the medial pillar of vessels (A). the location of the perforating branches coming from

the reduced breast. In our opinion. this vascular the internal mammary artery, running through the pectoralis major

supply to the medial part of the breast is much safer muscle and vascularising the medial pillar of the breast (B), and the site of division of the pectoralis major tendon (C).

222 British Journal of Plastic Surgery

than the procedure recommended by Copeland et a1.4 In their procedure, by elevating the skin flaps 6 cm from the midline perforating branches from the internal mammary vessels, passing through the pec- toralis major muscle to the overlying breast tissue, are unnecessarily cut, impairing the vascular supply of the medial pillar of the breast.

The treatment of sternomediastinitis in a patient with severe macromastia cannot be limited to radical sternal debridement with chest wall reconstruction by a rectus abdominis muscle flap without surgical cor- rection of the breast hypertrophy, as is demonstrated by the case reported. Three weeks after surgery, the temporary synmastia created by the large transfixion sutures was released and the wound opened inferiorly in a few days because of the traction of the heavy breasts. This clearly shows the need to address the problem of breast hypertrophy at the time of sternal debridement; the breast reduction should be part of the chest wall reconstruction, associated with muscle flap coverage of the sternectomy site. The musculog- landulocutaneous flap described in this paper meets this goal.

References

1. Sarr MG, Gott VL, Townsend TR. Mediastinal infection after cardiac surgery. Ann Thorac Surg 1984; 38: 415-23.

2. Ringelman PR, Vander Kolk CA, Cameron D, Baumgartner

WA, Manson PN. Long-term results of flap reconstruction in median sternotomy wound infections. Plast Reconstr Surg 1994; 93: 1208-14.

3. Thorek M. Possibilities in the reconstruction of the human form. NY Med J Ret 1922; 116: 572.

4. Copeland M, Senkowski C, Ergin A, Lansman S. Macromastia as a factor in sternal wound dehiscence following cardiac surgery: management combining chest wall reconstruction and reduction mammaplasty. J Cardiac Surg 1992; 7: 275-8.

5. Cormack GC, Lamberty BGH. The arterial anatomy of skin flaps. Edinburgh: Churchill Livingstone, 1986: 82-5.

6. Lejour M. Vertical mammaplasty and liposuction. St Louis: Quality Medical Publishing, 1994: 49.

7. Herrera HR, Ginsburg ME. The pectoralis major myocutaneous flap and omental transposition for closure of infected median stemotomy wounds. Plast Reconstr Surg 1982; 70: 465-70.

8. Jurkiewicz MJ, Bostwick J, Hester TR, et al. Infected median sternotomy wound. Ann Surg 1980; 191: 738-44.

The Authors

S. de Fontaine MD, Consultant Plastic Surgeon S. Devos MD, Registrar in Plastic Surgery D. Goldschmidt MD, Consultant Plastic Surgeon

Plastic Surgery Department, University Hospital Erasme, 808, route de Lennik, 1070 Brussels, Belgium.

Correspondence to Dr S. de Fontaine.

Paper received 1 September 1995. Accepted 15 December 1995.