Superficial wound dehiscence after median sternotomy: surgical treatment versus secondary wound healing.

BACKGROUND: Superficial wound dehiscence after midline sternotomy is considered a minor complication in cardiac surgery, although it is quite frequent and requires prolonged medical treatment. It can be managed conventionally by topical treatment, with delayed secondary healing, or by surgical treatment and primary skin closure. We report the outcome of 96 patients who underwent conventional treatment, compared with a second group of 42 patients who underwent surgical treatment and direct closure. METHODS: From October 1999 to December 2002, 2400 consecutive patients underwent median sternotomy: 207 patients had sternal wound complications: 3 patients (0.125%) had mediastinitis, 66 patients (2.75%) had aseptic deep sternal wound dehiscence, and 138 patients (5.75%) had superficial wound dehiscence. The latter are the object of the present study; patients entered a protocol of skin wound care on an outpatient basis. The first 96 consecutive patients (group 1) required medications three times a week until complete healing. The last 42 patients (group 2) were treated by extensive surgical debridement of skin and subcutaneous tissue, direct closure of the superficial layers, and suture removal after 15 days. RESULTS: The two groups were comparable as to age, sex, and preoperative risk factors. The incidence of contaminated wounds was similar in the two groups (32 of 96 in group 1 and 11 of 42 in group 2; p = NS). The length of treatment was 29.7 days (range 2 to 144 days) for group 1 and 12.2 days (range 2 to 37 days) for group 2 (p < 0.0001). The mean number of medical treatments was 9.4 per patient in group 1 and 3.7 per patient in group 2 (p < 0.0001). CONCLUSIONS: Surgical debridement and primary closure of superficial surgical wound dehiscence after median sternotomy is a safe and valid treatment. Wound infection is not a contraindication to surgical treatment. Primary closure may contribute to reduce the risk for later infection. It also definitely contributes to decreasing healing time and strongly lessens patients' discomfort, diminishing hospital costs and hospital staff workload.

Cardiac surgery in moderate to end-stage renal failure: analysis of risk factors.

BACKGROUND: The incremental surgical risk caused by different categories of renal failure is not well defined. METHODS: Data from 159 patients with moderate to end-stage renal dysfunction, who had consecutive operations using cardiopulmonary bypass, were included in a multivariate analysis of morbidity and survival. Ninety-nine patients had preoperative serum creatinine levels (PSCL) of 1.9 to 2.5 mg/dL (moderate), 36 had PSCL higher than 2.5 mg/dL and were not dialysis dependent (severe), and 24 required chronic dialysis (end-stage dysfunction). RESULTS: Operative mortality was 4% with moderate dysfunction and compared favorably with 16.7% in severe and 8% in end-stage dysfunction (p < 0.05). Independent predictors of death were severe non-dialysis-dependent renal dysfunction (p < 0.05), diabetes (p < 0.05), and cardiopulmonary bypass time (p < 0.01). Severe renal dysfunction (p < 0.01) and diabetes (p < 0.01) also predicted pulmonary and neurologic morbidity. Freedom from late death at 4 years was 82% +/- 5% with moderate, 49% +/- 10% with severe, and 60% +/- 10% with end-stage dysfunction (p < 0.01). Time to late death was adversely affected by severe (p < 0.05) and end-stage dysfunction (p < 0.01). Persistent improvement of symptoms was observed in all subgroups. CONCLUSIONS: Satisfactory early and late surgical outcomes may be expected in patients with moderate renal failure, but outcomes are often poor with severe non-dialysis-dependent and end-stage renal dysfunction.

Performance of a novel sternal synthesis device after median and faulty sternotomy: mechanical test and early clinical experience.

BACKGROUND: Reinforcement of chest closure may be required in patients with multiple risk factors of wound dehiscence. Performance of a light, size-adaptable closure reinforcement device (DSS: Sternal Synthesis Device; Mikai SpA, Vicenza, Italy) is presented. METHODS: A longitudinal median or paramedian incision was performed in artificial sternal models: closure was accomplished with simple interrupted steel wires or reinforced with the DSS. Forces required for separation of the rewired sternal halves during a monotonic tensile test were analyzed. A high velocity traction cycles test was also adopted to simulate the impact of coughing. RESULTS: After median incision, ultimate load values inducing break of the sternum models were 580 +/- 35 N (Newton) in controls; failure of the test occurred at 1,200 +/- 47 N in the reinforced group (p = 0.0002). More lateral displacement of sternal halves at increasing forces was observed in controls (p = 0.0001). After paramedian incision, ultimate load values inducing break of the constructs were lower in controls (220 +/- 20 N vs 500 +/- 25 N, p = 0.001), which also showed more lateral displacement of sternal halves than the reinforced group (p = 0.002). At the high velocity traction cycles test, the number of cycles required to break the models was lower in controls (2,250 +/- 35 vs 3,855 +/- 48 cycles, p = 0.0001). Preliminary clinical experience in 45 patients showed ease of implantation and low risk of complications. CONCLUSIONS: The proposed sternal reinforcement device provides substantial sternal support at electromechanical testing after median and faulty sternotomy and may hopefully prevent sternal wires migration and bone fractures in high risk patients.

[Surgery for type A aortic dissection: long-term results and risk factor analysis]. / La chirurgia della dissecazione acuta dell'aorta: risultati a lungo termine e fattori di rischio.

BACKGROUND: Identification of risk factors may help prevent mortality and recurrence after surgical treatment of type A aortic dissection. METHODS: From January 1995 to March 2006, 100 consecutive patients (82 men, 18 women, mean age 58 +/- 12 years) with type A acute aortic dissection were submitted to replacement of ascending aorta (n = 62), arch (n = 27), or the aortic root (n = 11, 9 with the Bentall operation and 2 with the David aortic valve reimplantation). Patients were followed up for 48 +/- 33 months (range 1-120 months). RESULTS: Operative mortality was 18% for aortic root replacement, 24% for ascending aorta replacement, 26% for arch replacement, respectively (p = NS). Independent risk factors for operative mortality were: acute (p = 0.001) and chronic renal dysfunction (p = 0.02), advanced patient age (61 +/- 13 vs 56 +/- 13 years, p = 0.02), prolonged bypass time (p = 0.01). Antegrade cerebral perfusion and moderate hypothermia during arch replacement was associated with better results than deep hypothermia (mortality 0/12 vs 7/15 patients, p = 0.008). Eight-year survival and freedom from cardiovascular events were 74 +/- 7.5% and 70 +/- 7.4%, respectively. Independent risk factor for late death was left ventricular ejection fraction < 0.50 (p = 0.02). Five out of 67 patients (7.5%) submitted to replacement of the ascending aorta with a tubular graft, who presented a dilated aortic root diameter (47 +/- 3.4 vs 40.4 +/- 4.9 mm, p = 0.004), were reoperated for proximal progression of the disease into the native aortic root (dilation n = 3, dissection n = 2) after 33 +/- 20 months (range 2-58 months). Proximal aorta reoperation was associated with markedly reduced 8-year survival (52 +/- 23 vs 82 +/- 7%, p = 0.017). CONCLUSIONS: Surgery for acute aortic dissection represents an emergency treatment with satisfactory long-term results. Survival is affected by renal dysfunction at presentation, which should be aggressively treated, and by progression of the disease requiring reoperation; a dilated diameter of the aortic root should therefore indicate root replacement at the time of first operation.

Benefit of partial right-bilateral internal thoracic artery harvesting in patients at risk of sternal wound complications.

BACKGROUND: Excellent long-term patency of the internal thoracic artery (ITA) graft promotes use of bilateral ITA bypass grafting; sternal devascularization, however, increases the risk of wound complications. We hypothesized that restricting right ITA (RITA) harvesting to a short proximal skeletonized segment (3 to 5 cm) would result in adequate residual blood supply to reduce that risk. METHODS: Seventy-eight patients with numerous risk factors for wound complications underwent composite double ITA grafting, utilizing the RITA segment anastomosed to the left skeletonized ITA and to the obtuse marginal branch in Y fashion. Blood flow in the distal RITA was assessed by parasternal transthoracic Doppler ultrasonography. Comparisons were made with prospectively collected data of patients undergoing pedicled single (n = 160) or skeletonized bilateral ITA grafting (n = 143) during the same period. RESULTS: Incidence of obesity, chronic obstructive pulmonary disease, diabetes, and peripheral vascular disease was higher in study patients. Postoperative Doppler ultrasonography detected reversed systolic dominant flow pattern. Wound complications occurred in 2 of 78 (2.6%) patients, compared with 14 of 143 (9.8%) after bilateral ITA (p = 0.04) and 8 of 160 (5%) after single ITA grafting (p = ns). Technique of bilateral ITA harvesting (partial right versus full length; odds ratio, 0.2; confidence interval: 0.04 to 0.9) and diabetes mellitus (odds ratio, 2.7; 95% confidence interval: 1.1 to 6.3) were independent predictors of wound complications in the entire series. CONCLUSIONS: Substantial residual blood supply is detectable after partial RITA harvesting and may prevent wound complications in high-risk patients.

Free right internal thoracic artery in a "horseshoe" configuration: a new technical approach for "in situ" conduit lengthening.

Severe chronic obstructive pulmonary disease with large lung volumes may prevent both the "in situ" internal thoracic arteries to reach coronary anastomoses sites. We present a method to revascularize the left antero-lateral myocardial wall using the right internal thoracic artery as a "free graft" anastomosed side to end to the "in situ" left internal thoracic artery, in a "horseshoe" fashion. The two ends of the "free graft" were anastomosed to the left anterior descending coronary artery and the second obtuse marginal branch, respectively. This method was successfully used in a 74-year-old patient with severe chronic obstructive pulmonary disease.

Partial right internal thoracic artery harvesting is sufficient for obtuse marginal branch bypass grafting.

My colleagues and I present a method for revascularizing the left anterolateral myocardial wall by using an in situ left internal thoracic artery to left anterior descending coronary artery system and a short proximal segment (3 to 5 cm) of the right internal thoracic artery in Y fashion anastomosed to the in situ left internal thoracic artery to revascularize the obtuse marginal branches. With this technique the left ventricular anterolateral wall can be revascularized with both internal thoracic arteries, leaving a consistent residual blood supply to the right hemisternum.

Small "functional" size after mechanical aortic valve replacement: no risk in young to middle-age patients.

BACKGROUND: The impact of a valve prosthesis-patient size mismatch is still controversial. In most studies, the inclusion of a large proportion of poorly active old patients with low cardiac output requirements may be misleading, due to the close correlation between trans-prosthetic gradients and cardiac output. The aim of this study was to assess the impact of small "functional" prosthesis sizes in active young to middle-age patients. METHODS: Eighty-three active patients with a mean age of 46 +/- 8 years and a high health survey questionnaire score were followed for 80 +/- 34 months after isolated aortic valve replacement with a mechanical prosthesis. RESULTS: Patients with an indexed, Doppler derived, effective orifice area index less than 0.85 cm2/m2 (0.77 +/- 0.1 cm2/m2) showed higher early trans-prosthetic gradients (peak, 34 +/- 11 vs 26 +/- 8 mm Hg; P = 0.001) than patients with a larger effective orifice area index. However, significant regression of the left ventricular mass index and improvement of the left ventricular ejection fraction were observed in both groups at follow-up (119.8 +/- 26 vs 165.2 +/- 38 g/m2 and 128.5 +/- 25 vs 181.8 +/- 50 g/m2; P < 0.001; 58 +/- 6 vs 52 +/- 11% and 58 +/- 7 vs 53 +/- 10%; P < 0.001), with no differences between groups (P = 0.4 and P = 0.7, respectively). At multiple linear regression, the final left ventricular mass index was positively related to the preoperative left ventricular mass index (P = 0.004) and was unaffected by the effective orifice area index (P = 0.4). Symptomatic improvement (New York Heart Association class 1.3 +/- 0.4 vs 2.4 +/- 0.8 and 1.2 +/- 0.4 vs 2.2 +/- 0.8; P < 0.001) and freedom from late cardiac death (93 +/- 3% and 95 +/- 6%) were comparable between groups (P = 0.6 and P = 0.7, respectively). CONCLUSIONS: Our findings indicate that small "functional" prosthesis sizes with modern mechanical valves may not adversely affect outcomes of aortic valve replacement in young patients with high cardiac output requirements.