Infective endocarditis complicated by paravalvular abscess: a surgical challenge. An 11-year single center experience.

AIM: To evaluate the impact of paravalvular abscess in the surgical management and outcome of infective endocarditis. METHODS: Retrospective review of 35 patients with paravalvular abscess due to active endocarditis operated on at 1 institution from September 1996-August 2007. Patients' mean age was 59.4 +/- 12.1 years; 80% were men. 31 patients suffered from native- and 4 from prosthetic valve endocarditis. In 23 cases the affected valve was the aortic, in 7 cases the mitral, in 4 cases both (mitral and aortic), and in 1 patient the tricuspid; no abscess presence was noticed by pulmonal annuluses. Surgical procedures included radical lesion-resection as well as reconstruction of the annulus with pericardial patches. Most of the patients were preoperatively in New York Heart Association (NYHA)-class III-IV. Follow-up was 100% complete with a maximum of 11.25 years. RESULTS: Early mortality (30 days) was 11.4% (n = 4). The 11-year overall survival rate was 68.7 +/- 9% (76.1% for aortic valve patients and 26.9% for mitral valve patients (P = .15). With regard to the type of prosthetic devices, the survival rates at 11.25 years were 74.2% for mechanical, 80% for biological, and 45.6% for other/reconstructive (P = .6). There were no episodes of recurrent endocarditis; hence freedom of recurrent endocarditis at 11 years was 100%. Causative microorganisms were approximately 30% Staphylococci, and MRSA seems to induce more frequent destructive lesions like paravalvular abscess. CONCLUSIONS: Considering the severity of the onset, a radical surgical treatment delivers acceptable long-term results by acceptable operative mortality. The choice of the prosthetic device seems not to be influential in long-term survival and morbidity.

Search for optimized conditions for sealing and storage of bypass vessels: influence of preservation solution and filling pressure on the degree of endothelialization.

The aim of the present study was to develop methods for the rapid assessment of intimal quality of coronary bypass segments of venous origin, and to prevent endothelial damage by improved intraoperative handling of graft segments. Particular attention was paid to the influence of the composition of the preservation solution and the intravasal filling pressure on the degree of endothelialization. Intrava-sal exposure to Alcian blue at pH<3 resulted in highly specific staining of intimal regions with functionally or structurally damaged endothelium. Standardization of preparation, staining and image acquisition of the intimal surface of graft remnants and subsequent computer-aided planimetry of these images made it possible for the first time to perform rapid serial investigations for quality control of bypass grafts. Using saline as the rinsing and intraoperative storage medium resulted in the loss of more than 50% of the endothelium at intravasal pressures of 0-100 mmHg. Increasing the pressure resulted eventually in complete de-endothelialization. In contrast, grafts incubated in a customized plasma derivative tolerated pressures of up to 200 mmHg with no significant endothelial loss; and even after exposure to 1,000 mmHg (10 times the average mean arterial pressure!) more than 70% of the endothelium were intact and vital. These findings imply strongly that the quality of aortocoronary bypass grafts of venous origin can be improved substantially by the use of a plasma derivative solution for intraoperative preservation and by monitoring and controlling the intravasal pressures reached during sealing and storage.

Does bilateral ITA grafting increase perioperative complications? Outcome of 4462 patients with bilateral versus 4204 patients with single ITA bypass.

OBJECTIVE: Superior patency of internal thoracic artery (ITA) grafting to saphenous veins is conclusive. The aim of the present study was to compare the early outcome of patients receiving either bilateral ITA (BITA) or single ITA (SITA) grafts and to identify risk factors for perioperative complications, such as obesity, diabetes mellitus, or advanced age. METHODS: All 8666 patients with isolated coronary artery bypass grafting (CABG, including emergent cases or redos) operated between January 1994 and June 2004 receiving either BITA (n=4462) or SITA (n=4204) grafting were analyzed retrospectively. Demographic data were comparable for both groups concerning mean age (65.3+/-9.4 years vs 64.9+/-9.3 years), range (35-89 years (p=0.05)), diabetes incidence (29.3% vs 2.6% (p=0.08)), dialysis-dependent renal failure (0.7% vs 0.6% (p=0.4)), preoperative ejection fraction (EF) mean (61.8% vs 61.2% (p=0.07)) but not for gender (80.4% vs 76.7% males (p=0.00)), body mass index (BMI) mean (27.2+/-3.6 vs 26.9+/-3.5 (p=0.00)), COPD (7.0% vs 8.5% (p=0.00)), and hyperlipidemia (78.3% vs 74.3% (p=0.00)). In the BITA group, right ITA (RITA) was directed preferentially to the left anterior descending artery (LAD), left ITA (LITA) to the lateral wall. In the SITA group, the LAD was revascularized with the left ITA. Additional bypasses were performed with saphenous vein grafts (SVG). RESULTS: The number of anastomoses was higher in the BITA group (3.8+/-0.9 vs 3.1+/-0.9 (p=0.00)); therefore, duration of surgery (mean: 189+/-46.3 min vs 164+/-46.2 min) and cross-clamp time (62.0+/-17.9 min vs 51.0+/-18.0 min) significantly prolonged (p=0.00). Incidence of rethoracotomy due to bleeding (2.9% vs 0.6%; p=0.00) or sternal refixation with (0.7% vs 0.2%; p=0.00) or without infection (1.4% vs 0.6%; p=0.00) was higher in the BITA group, strongly associated with diabetes mellitus and duration of surgery but not with BMI>27. Thirty-day mortality revealed 2.6% versus 3.2% (p=0.1) but was significantly lower for diabetic patients in the BITA group (3.1% vs 4.7%; p=0.00). CONCLUSIONS: CABG using both ITAs can be performed routinely with good clinical results and low mortality. Compared with single ITA grafting, sternal and bleeding complications were slightly increased. Diabetes mellitus, BITA grafting, duration of surgery but not obesity or COPD could be identified as independent risk factors for sternal complications. Dialysis-dependent renal failure, EF<30%, emergent cases, and the absence of BITA grafting were predictors for increased perioperative mortality.