Is extreme obesity a risk factor for increased in-hospital mortality and postoperative morbidity after cardiac surgery? Results of 2251 obese patients with BMI of 30 to 50.

OBJECTIVE: The number of patients with extreme obesity requiring cardiac surgery is increasing. The aim of the present study was to evaluate the perioperative outcome, complication rate and 30-day mortality of these patients. METHODS: Data of 13 139 patients (9584 males, 3555 females) undergoing cardiac surgery from 1/94 to 12/04 were analyzed. We compared 2251 obese patients with a BMI of 30 to 50 (mean age 64.3 years; group A) with 10 888 non-obese patients (mean age 66.1 years; group B). The incidence of diabetes mellitus was 34.5 % in group A, and 24.2 % in group B. RESULTS: Isolated CABG was performed in 1771 patients from group A (3.4 grafts/pt.) and in 8066 patients from group B (3.2 grafts/pt.). Concomitant procedures were performed in 460 patients (group A) vs. 2645 (group B). Frequency of bilateral internal thoracic artery grafting was 49.4 % (group A) vs. 44.9 % (group B). There were no significant differences between the two groups with regard to the duration of surgery (180 vs. 171 min), the number of reoperations for bleeding (4.7 % vs. 5.0 %), ventilation times, length of stay in the intensive care unit (2.6 vs. 2.4 days) or 30-day mortality (2.0 % vs. 2.8 %). The incidence of diabetes and occurrence of sternal dehiscence was higher in group A (1.6 % vs. 0.7 %; P < 0.01). Sternal complications were strongly associated with diabetes and the combined use of bilateral ITA grafts but not with isolated obesity. The incidence of sternal dehiscence was associated with the male gender (group A 1.9 % vs. 0.7 %; group B 0.9 % vs. 0.3 %). CONCLUSION: Severe obesity does not PER SE enhance perioperative mortality. A BMI of 30 to 50 combined with diabetes mellitus and bilateral ITA grafting increases the risk for sternal complications.

Patency of internal thoracic artery compared to vein grafts - postoperative angiographic findings in 1189 symptomatic patients in 12 years.

BACKGROUND: The evidence respecting the superior patency of ITA-grafts compared to SVG is conclusive. This study evaluates the angiographic findings in 1,189 symptomatic patients who received either one or both ITA-grafts with or without additional SVG. METHODS: 1,189 patients (975 males, aged 62.4 +/- 9.1 years), operated between 2/93 and 7/05, underwent angiography due to reappearance of angina. Data were compared for patency of single ITA (n = 618), bilateral ITA (n = 416) or SVG (n = 2,218). Re-catherization was performed after 3.8 +/- 2.7 years. Severe bypass stenosis or graft occlusion was related to the target vessels. RESULTS: 3,668 bypasses were performed in 1189 patients. The occlusion rate was 16.5 % for SVG and 7.0 % for all ITAs ( P < 0.001). Severe stenosis was detected in 4.8 % of SVG and in 3.7 % of ITAs ( P < 0.05). Patency was 89.6 % for LITA, 88.7 % for RITA, and 78.7 % for SVG. The occlusion rate for LITA was: to LAD 6.6 %, DIA 8.5 %, obtuse marginal branch/CX 11.5 %. The occlusion rate for RITA was: to LAD 4.6 %, RCA 9.1 %., diag. branch 7.1 %. The occlusion rate for vein grafts was: to LAD 17.3 %, DIA 14.4 %, obtuse marginal branch/CX 15.9 %, to RCA 17.0 %. Patency for all ITAs was 89.3 % vs.78.7 % for all SVG ( P < 0.05). Despite symptoms, bypass patency was found in 711 patients (59.8 %). CONCLUSION: The superior patency of ITA-grafts could be documented angiographically in a negatively selected, symptomatic population. Graft occlusion was at least twofold higher for SVG.

Is there a difference between diabetic and non-diabetic ITAs? Histomorphological and immunohistochemical examinations of internal thoracic arteries.

BACKGROUND: The relative resistance to arteriosclerosis of the internal thoracic artery is clinically valid. The aim of this study was to evaluate the graduation of intima and media fibrosis in ITA parts and to determine the extent of atherosclerosis using immunohistochemical methods related to patients' risk factors. METHODS: 227 distal ITA segments from 144 male and 83 female patients were examined. Mean age was 66.7 +/- 9.03 years. HE and Elastica van Gieson staining was performed to detect intima-/mediafibrosis. POPULATION: insulin-dependent diabetes mellitus (idDM; n = 35), non-insulin-dependent diabetes mellitus (nidDM; n = 32), irradiation of the chest due to cancer (n = 27), control group with isolated hyperlipidemia, hypertension, peripheral vascular disease (n = 133). 12 ITA segments of each group were examined immunohistochemically using CD34, CD68, Tenascin, Collagen III, Collagen IV. RESULTS: Histomorphological examinations using HE and Elastica van Gieson stainings showed for idDM-ITAs no fibrosis in 57 %, slight fibrosis in 34 %, medium in 6 %, no severe, for nidDM-ITAs no fibrosis in 63 %, slight 31 %, medium 3 %, severe 3 %, for ITAs after irradiation: no fibrosis in 37 %, slight in 62 %, no medium or severe fibrosis. Compared to the control group there was no statistically significant difference in diabetic ITAs. Immunohistochemical examinations, scored on a 0 - 3 basis with 0 being the lowest (no reaction), 3 the highest (severe reaction), showed mostly no or slight reaction to CD34, CD68, Tenascin, and Collagen III for intima and media, with comparable results for diabetic or "irradiated" ITAs to those of the control group. The most distinct reaction (medium= 2), was detected for Collagen IV, a marker which outlines basement membranes of endothelia and smooth muscle cells of the vessel wall, but without differences between the four groups. No severe reactions were observed. CONCLUSIONS: The relative resistance of ITA to arteriosclerosis could be demonstrated in 227 ITA segments. Immunohistochemistry supports histomorphological findings. The influence of diabetes mellitus and irradiation remains irrelevant.

Internal thoracic artery vs. vein grafts--postoperative angiographic findings in symptomatic patients after 1000 days.

BACKGROUND: Superior patency-rate of ITA, especially BITA-grafting to saphenous vein grafts, is conclusive. This study evaluates angiographic findings postoperatively in 663 symptomatic patients receiving one or both ITAs and vein grafts. METHODS: 663 patients (553 male, mean age 62) with CABG operated between 1/94 and 6/02 underwent reangiography due to reappearance of angina or unclear cardiac symptoms. Angiographic data were compared for patency rate of single ITA (n = 379), bilateral ITA (n = 220) or vein grafts. Recatherization was performed after an average of 1000 days (+/- 766 days). Severe bypass stenosis or occlusion was related to target vessels for all grafts. RESULTS: 2099 Bypasses were performed in 663 patients. Severe stenosis or occlusion was detected in 255 ACB (19.9 %) of 1280 and 93 ITAs of 819 (11.4 %, p < 0.001). Patency was 88.8 % (532) for LITA, 88.2 % (194) for RITA. Target vessels were as follows: LITA: 60 % (358) LAD, 23.5 % (141) CX, RITA: 82 % (180) LAD. Occlusion rate for LITA was as follows: to LAD 7 %, to DIA 8.7 %, to CX 8.5 %. Occlusion rate for RITA as follows: to LAD 6.7 %, to DIA 16.7 %, to CX 0, to RCA 14.3 %. Occlusion rate for ACB was as follows: to LAD 18.7 %, to DIA 12.6 %, to CX 14.1 %, to RCA 16.1 %. Despite symptoms, bypass patency was observed in 412 (62.1 %) of 663 patients. CONCLUSIONS: Superior patency of ITA, especially BITA grafting could be documented angiographically in a negative selected symptomatic population. Graft occlusion was nearly two fold higher in vein grafts. Our surgical strategy, revascularizising RITA with LAD, LITA with circumflex artery results in satisfactory mid-term graft patency.