Iatrogenic right coronary artery stenosis resulting from surgical tricuspid valve replacement: case report and review of the literature.

Iatrogenic injury to the right coronary artery (RCA) is a rare complication of tricuspid valve surgery. We herein describe the first-ever report of RCA injury related to tricuspid valve replacement surgery. A 38-year-old man with recurrent tricuspid endocarditis underwent redo tricuspid valve replacement by means of a minimally invasive right thoracotomy with a 32-mm St. Jude bioprosthetic valve. His post-operative course was complicated by pulseless ventricular tachycardia requiring CPR and defibrillation. Cardiac catheterization revealed a "kinked" stenotic distal RCA. The lesion was noted to be flow limiting by fractional flow reserve and was treated with two everolimus-eluting stents. The RCA runs in the atrioventricular groove and is susceptible to injury especially in the region of the posterior leaflet of the tricuspid valve, where the relationship of the tricuspid annulus to the RCA is most intimate. Repair of surgically induced coronary stenosis can be accomplished with percutaneous intervention.

Laser Doppler flowmetry assessment of peristernal perfusion after cardiac surgery: beneficial effect of negative pressure therapy.

Negative pressure therapy has been successfully applied to clean, closed incisions in patients at high-risk for wound complications. Using laser Doppler flowmetry, we evaluated peristernal perfusion after cardiac surgery via median sternotomy, assessing the influence of mammary artery harvesting and the impact of negative pressure therapy. Twenty adult patients underwent median sternotomy for cardiac surgery followed by routine closure. Negative pressure was applied at 125 mm Hg for 4 days postoperatively in patients with increased risk for wound complications (n = 10, negative pressure group); standard dressings were applied to control incisions postoperatively (n = 10). Presternal perfusion was determined at baseline and daily for 4 days postoperatively using laser Doppler flowmetry. Results within and between groups were compared with analysis of variance. No wound complications were encountered in either group. Perfusion increased among the patients who underwent negative pressure therapy and decreased among the controls (P = 0.004). Mammary artery harvesting reduced peristernal perfusion by 25.7% in the controls, but negative pressure increased perfusion by 100% after mammary harvesting (P = 0.04). Negative pressure therapy increased perfusion relative to controls and compensated for reduced perfusion rendered by mammary artery harvesting, providing additional support for 'well wound therapy' in high-risk patients.

Modified ultrafiltration attenuates pulmonary-derived inflammatory mediators in response to cardiopulmonary bypass.

Cardiopulmonary bypass (CPB) stimulates systemic and pulmonary inflammation. Modified ultrafiltration (MUF) mitigates deleterious CPB effects by unclear mechanisms. We evaluated pulmonary inflammation in piglets undergoing CPB followed by MUF. Twenty-four piglets underwent 60 min of hypothermic CPB. MUF subjects (n=12) underwent hemoconcentration postCPB to the target hematocrit. Pulmonary vascular resistance (PVR), proinflammatory cytokine concentrations, and transpulmonary thromboxane gradients were determined at baseline, following CPB, and at end of the study (EOS) in MUF and control (n=12) groups. PVR significantly increased postCPB in both groups but decreased after MUF. MUF and control groups were similar in regards to systemic cytokine concentrations. Bronchoalveolar lavage concentrations of IL-6 and IL-8 significantly increased in controls throughout the study. Alveolar IL-6 and IL-8 were unchanged at EOS in MUF subjects, and IL-6 concentrations were significantly less than controls at EOS (P=0.015). Similarly, transpulmonary thromboxane gradient was significantly less at EOS in MUF subjects compared with controls (P=0.04). MUF removed circulating inflammatory mediators, lessened pulmonary hypertension, and reduced pulmonary-derived inflammatory markers, providing further evidence that MUF ameliorates pulmonary-based inflammation. These findings lend insight into mechanisms behind salutary clinical benefits of MUF after CPB.

Does negative pressure wound therapy have a role in preventing poststernotomy wound complications?

BACKGROUND: Sternal wound infection (SWI) remains a devastating complication after cardiac surgery, decreasing long-term and short-term survival. In treating documented SWI, negative pressure wound therapy (NPWT) reduces wound edema and time to definitive closure and improves peristernal blood flow after internal mammary artery (IMA) harvesting. The authors evaluated NPWT as a form of "well wound" therapy in patients at substantial risk for SWI based on existing risk stratification models. METHODS: Records of 57 adult cardiac surgery patients (September 2006 to April 2008) were reviewed. After preoperative risk assessment, NPWT was instituted on the clean, closed sternotomy immediately after surgery and continued 4 days postoperatively. Adverse postoperative events, including SWI, need for readmission, and other complications, were documented. RESULTS: Mean age was 60.4 +/- 10 years, and 89.5% were male; 77.2% were obese (mean body mass index 35.3 +/- 6.7), 54.4% were diabetic, and 29 (50.9%) were both obese and diabetic. Coronary artery bypass (CAB) with single IMA was performed in 50.9% of the patients followed in frequency by combined CAB/valve, non-CAB surgery, and CAB with bilateral IMA. Estimated risk for SWI was 6.1 +/- 4%. All patients tolerated NPWT to completion. Thirty-day and in-hospital mortality was 1.8% and unrelated to DSWI. No treatment of SWI was required. CONCLUSIONS: In this high-risk cohort, 3 postoperative SWI cases were anticipated but may have been mitigated by NPWT. This is an easily applied and well-tolerated therapy and may stimulate more effective wound healing. Among patients with increased SWI risk, strong consideration should be given to NPWT as a form of "well wound" therapy.

Use of negative pressure therapy on closed surgical incisions: a case series.

Multiple patient comorbidities and environmental factors increase the risk of incisional wound complications. The literature suggests that negative pressure therapy (NPT) on clean closed surgical incisions may help reduce the risk of wound infections and other complications. In this case study, NPT was applied in the operating room to clean closed surgical wounds in four high-risk patients (two men, two women) following coronary artery bypass grafting using bilateral internal mammary arteries, transmetatarsal amputation, and abdominal hysterectomy. All wounds healed well. These results and currently available information suggest that prospective, randomized, controlled clinical studies to assess the safety, efficacy, and cost-effectiveness of NPT in the prevention of postoperative wound complications are warranted. In addition, if studies confirm the validity and reliability of the proposed patient grading system discussed, it may help guide use of NPT in postsurgical patients.