Mohamad N. Bittar

Interleukin 6 G-174C polymorphism influences outcome following coronary revascularization surgery.

BACKGROUND Levels of the proinflammatory cytokine interleukin 6 (IL-6) increase after surgery. The functional polymorphism in the IL-6 promoter region, G-174C, is associated with an increased risk of coronary heart disease. We investigated the genetic predisposition in IL-6 response to coronary revascularization and studied the association between the G-174C polymorphism, IL-6 levels, and clinical outcomes of surgery. METHODS DNA was obtained from 96 consecutive patients who underwent elective coronary revascularization. Patients were genotyped for the IL-6 G-174C polymorphism by means of sequence-specific primer-polymerase chain reaction analysis. IL-6 levels were measured with an enzyme-linked immunosorbent assay on serum samples taken 3 hours postoperatively. IL-6 levels and genotypes (CC, CG, and GG) were correlated with perioperative clinical data. RESULTS The prevalences of the CC, CG, and GG IL-6 -174 genotypes were 8%, 54%, and 38%, respectively. Patients homozygous for the C allele had higher circulating levels of IL-6 postoperatively than the patients with the CG and GG genotypes (P = .09). Patients homozygous for the G allele had a significantly lower incidence of postoperative atrial fibrillation (P = .032) and a shorter hospital stay (P = .005). This result remained statistically significant following risk stratification. The severity of coronary artery disease and a higher number of bypass grafts were associated with a significant increase in IL-6 level postoperatively (P = .028, and P = .005, respectively). Higher levels of IL-6 were associated with increased blood loss postoperatively (P = .016). CONCLUSIONS The C allele is associated with higher postoperative IL-6 levels and a less favorable clinical outcome. The G-174C polymorphism is related to the outcome after coronary revascularization.

Endovascular versus open surgical repair for blunt thoracic aortic injury

A best evidence topic in vascular surgery was written according to a structured protocol. The question addressed was whether patients with acute traumatic thoracic aortic injury have a better outcome with endovascular or open surgical repair. Altogether, 283 papers were found using the reported search, of which five represented the best evidence to answer the clinical question. The author, journal, date and country of publication, patient group studied, study type, relevant outcomes, results, and study weaknesses of these papers are tabulated. We concluded that the peri-procedural mortality rate for patients with traumatic thoracic blunt aortic injury is lower for patients treated with an endovascular stent graft when compared to the open technique. This important benefit is at the cost of a high procedure complication rate, requirement for long-term surveillance of the stent and uncertain medium and longer-term outcome.

Massive hemothorax secondary to metastatic renal carcinoma.

We present the case of a 78-year-old man with a past history of nephrectomy for renal cell carcinoma who was brought to the emergency room in hypovolemic shock after suddenly collapsing at home. A chest roentgenogram taken on admission showed a large pleural effusion on the right with a mediastinal shift to the left. A contrast computed tomographic scan of his chest excluded aortic dissection. An emergency right thoracotomy was performed, which revealed a chest wall tumor that was bleeding profusely. The tumor was biopsied after the bleeding was controlled. The histologic report revealed metastatic renal cell carcinoma, which is a rare cause for a spontaneous massive hemothorax.

Interleukin-4 C-590T Polymorphism Has No Role in Coronary Artery Bypass Surgery:

Interleukin-4 exerts anti-inflammatory effects through decreased macrophage production of tumor necrosis factor-α and interleukin-1ß. We investigated genetic predisposition in the interleukin-4 response to coronary revascularization and studied the association between C-590T polymorphism, interleukin-4 levels, and outcome of surgery. DNA was obtained from 96 consecutive patients undergoing elective coronary revascularization. Patients were genotyped for interleukin-4 C-590T polymorphism using a sequence-specific primer polymerase chain reaction. Interleukin-4 levels were measured using an enzyme-linked immunosorbent assay in serum samples taken 3 hr postoperatively. The frequency of interleukin-4 C-590T genotypes CC, CT, and TT was 33.3%, 27.1%, and 39.6%, respectively. Patients with the TT genotype had significantly higher circulating levels of interleukin-4 (3.4 ± 4.6 pg·mL−1) postoperatively compared to CC (2.5 ± 0.1 pg·mL−1) and CT (2.7 ± 0.5 pg·mL−1) genotypes. Interleukin-4 C-590T polymorphism is the main determinant of postoperative interleukin-4 levels. The TT genotype is the highest producer of interleukin-4. Neither the genotype nor the serum levels seem to play any role in recovery from coronary artery bypass surgery.

DONOR HEART SELECTION: WYTHENSHAWE EXPERIENCE

BACKGROUND The decline in the number of suitable donor hearts has led to an increasing interest in the use of previously unacceptable donors. This study aimed to evaluate the outcome of recipients of donor hearts considered medically unsuitable for transplantation at this center that were used in other centers in the United Kingdom. METHODS Forty donor hearts (group 1) were declined by Wythenshawe Hospital and used in other units in the United Kingdom in the period extending from April 1998 to March 2003. One hundred four hearts (group 2) were transplanted at Wythenshawe Hospital during the same period. Donors and recipient data were obtained from the United Kingdom Cardiothoracic Transplant Audit database. Mortality in both groups was analyzed using SPSS software. RESULTS Mortality in patients receiving grafts from group 1 donors was significantly higher than in group 2 (P < .0009). Of the early deaths in this group 50% (6 of 12) were the result of graft failure. These donors were receiving high doses of inotropes, had ischemic time exceeding 3.5 hours, and the grafts were transplanted into high-risk patients. CONCLUSION Hearts declined on medical grounds by one center should be evaluated with caution before being considered suitable for transplantation, especially when more than one adverse factor is present.