Latissimus Dorsi Flap in the Treatment of Thoracic Wall Defects After Medial Sternotomy

Adam Stepniewski, MD; Joelle Krahlisch, MD; Alexander Emmert, MD; Ahmad-Fawad Jebran, MD; Maximilian Schilderoth, MD; Helen Synn, MD; Gunther Felmerer, MD

Disclosures

ePlasty. 2020;20(e4) 

In This Article

Discussion

The most common method for closure of defects after medial sternotomy is the use of pedicled latissimus dorsi flap. The architecture of this myocutaneous flap[6,7] allows for the reconstruction of the defect with the possibility of filling large cavities with well-perfused muscle, thus protecting the area from bacterial contamination and accelerating tissue recovery.[8]

In our study, the proportion of patients with a survival rate of 1 year was 84.00% (21/25 patients) and the proportion with a 2-year survival rate was 80.00% (20/25 patients), and these results correspond with those from other literature.[9]

Moreover, we demonstrated a significant association between postoperative complications and decreased survival rates. Both early and late complications had a strong influence on the survivability (P < .00002). We calculated the presence of postoperative complications with a hazard ratio of 2.965 (95% confidence interval 0.845–3.13), making it one of 3 high-risk prognostic factors.

The most influential factor of the survival rate was the presence of acute renal failure,[10] either as an isolated condition or due to preexisting renal insufficiency (P = .00003); lethality for patients who underwent treatment was up to 70%.

According to Krug et al,[11] complication rates are increased when the person smokes more than 20 cigarettes a day, but occasional smokers or ex-smokers do not have an increased risk of wound-healing delays or local necroses. Based on our results, a significant correlation between nicotine consumption and lower survival rate (P = .034) was observed but not between necroses or wound-healing delays and lower survival rates (P = 0.791). However, a small number of patients could have biased our results (10 active smokers, mean = 30.00 ± 8.66 pack-years; 6 ex-smokers, mean = 38.33 ± 24.01 pack-years).

The fourth factor, which showed a significant correlation for diminished survival rates, was the metabolic syndrome (P = .004). In addition, the mean survival rate of patients with the metabolic syndrome was 35.50 ± 24.44 months whereas that of patients without the metabolic syndrome was 45.83 ± 20.31 months in our study. Metabolic syndrome can lead to complications because the weight of fat tissue and skin can cause longitudinal or perpendicular traction on the wound edges and prevent tissue perfusion. Furthermore, it may interfere with surgical suturing.[12] Although a significant correlation between metabolic syndrome and the occurrence of complications was not found in our study (P = .842), we propose that the presence of the metabolic syndrome can be treated as a negative prognostic factor (hazard ratio: 6.27; 95% confidence interval, 1.53–25.62).

The grade of local infection or the presence of sternal osteitis depends on the extent of the debridement surgery. The insufficient debridement and infection control can lead to enlargement of the sternal defect and create the unstable thorax wall. The surgical time can be consequently much longer if the defect requires a larger latissimus flap.[13] According to our results, insufficient debridement and the presence of persistent osteitis decreased the survival rate (P = .780). The patients who had minor infection had the highest survival rate (45.59 ± 28.12 months). Interestingly, patients with pronounced local infection lived longer than those with moderate infection (38.70 ± 13.54 months vs 36.78 ± 23.96 months). Thus, we can hypothesize that large infections can also be treated successfully. However, it requires sufficient debridement.

Further investigation of a potential correlation between the length of time between sternotomy and flap surgery and the survival rate is needed (P = .075). Patients with the sternal defect who were operated on to create the latissimus flap 76 to 152 days after sternotomy had the greatest survival rate of 61.33 ± 14.01 months. A lower patient survival rate was found when the period between 2 operations was longer than 152 days (36.07 ± 3.33 months). Unfortunately, it is not clear whether the vacuum-assisted therapy was employed as an additional process to prepare the target area for latissimus flap surgery or as an exclusive method prior to flap surgery. In the other studies, it is stated that a vacuum-assisted closure therapy can improve the overall outcome of treatment.[14]

In our study, the period during which the complete surgery occurred was remarkably long. Therefore, it is important to investigate whether an abbreviated period between surgical procedures could have improved the outcome. The patients were transferred from another department, and flap surgery was completed immediately after the takeover. The flap operation was carried out by plastic surgeons on average a week after the takeover from another department.

An important feature of our study is that the questionnaires were formulated for patients to evaluate their respiratory function and quality of life. Most of the patients did not report changes in their breathing patterns after sternotomy or a combination of sternectomy and flap surgery. However, it was only a subjective assessment and no objective evaluation, such as pulmonary function testing, was done. This can be one of the limitations of our study.

In the literature, there were no differences in pulmonary function between the cases with conventional sternotomy and those with complete sternectomy without stabilizing the thoracic wall.[15] Leaving a wide bony gap after sternectomy can prevent painful friction, which can reduce the patient's quality of life.[16] Because one of our patients reported this chest pain after the sternectomy, it was important to consider this procedure in our study. Furthermore, 2 patients reported dyspnea, especially during physical activity, which was described as impairing the quality of life.

The overall subjective evaluation showed more positive results in early follow-up inpatient treatment after surgery (1.86 ± 1.03) compared with the later follow-up care in September 2017 (1.93 ± 1.21; 1.0 = very good, 5.0 = poor). One of the other factors, which could have contributed to a positive subjective outcome, was the relatively short hospital stay after flap surgery. Compared with those who experienced a longer stay due to complications resulting from sternotomy, the patients who had relatively quick recovery after latissimus flap surgery reported it as a great benefit to them.

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