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Background: Systolic dyssynchrony is present in a considerable number of patients with heart failure (HF) undergoing coronary artery bypass grafting (CABG). Surgical revascularization offers an optimal setting for totally epicardial cardiac resynchronization therapy (CRT) system implantation. Aim: To assess the efficacy of totally epicardial CRT implantation during CABG, in patients with HF. Methods: Twenty three patients with HF and dyssynchrony underwent totally epicardial CRT system implantation during CABG. This randomised, single-blind, cross-over study compared clinical and echocardiographic parameters during two periods: 3 months of active CRT (CRT+) and 3 months of inactive CRT (CRT−) pacing. Results: Twenty two patients underwent randomisation and completed both study periods. In the CRT+ group more patients improved by two NYHA classes (p=0.028), had a longer 6-minute walk test distance (p=0.047) and better quality of life (p=0.003) compared with the CRT− group. Echocardiography revealed an improved LV ejection fraction (p

Objective: The saphenous vein subjected to arterial pressure stretches to its elastic limits and constitutes intimal hyperplasia. Sheathing of the vein graft with pressure-resistant tubing might prolong vein graft patency. Methods: Twenty-one sheep received radial vein grafts or hybrid grafts composed of radial vein, collagen fibrin glue and highly flexible torlen/dacron mesh tubing transplanted into the carotid artery position. Veins were examined with the use of light and electron microscopy. Proliferating cell antigen (Ki-67) stains served as markers of proliferation. Results: The mean wall thickness of both intimal and medial layers was evaluated. The mean intimal wall thickness was 19 ^ 11 mm in hybrid grafts vs. 24 ^ 7 mm in unsheathed grafts (P , 0:001); 22 ^ 6 vs. 26 ^ 10 m m( P , 0:001); 23 ^ 8 vs. 52 ^ 15 mm (P , 0:001); 37 ^ 21 vs. 90 ^ 31 m m( P , 0:001); 57 ^ 31 vs. 104 ^ 28 m m( P , 0:001); 58 ^ 21 vs. 133 ^ 32 m m( P , 0:001); and 72 ^ 22 vs. 244 ^ 100 m m( P , 0:001) after respectively 5 days, 9 days, 4 weeks, 6 weeks, 8 weeks, 10 weeks and 12 weeks from implantation. Electronic microscope examination of hybrid grafts revealed a smooth endothelial layer with intact nuclei and an intima composed of layers of collagen and muscle fibers. In unsheathed grafts endothelial edema and nuclear destruction were observed. Conclusions: The external vein graft support with mesh tubing reduces intimal and medial layer thickening and cell proliferation in composite vein grafts transplanted in the arterial position. q 2002 Elsevier Science B.V. All rights reserved.

Objective: Troponin T is a unique marker which might be particularly useful in assessing myocardial cell damage in patients undergoing cardiac surgery. The aim of the study was a comparison between intra-operative release of troponin T (TnT) during three different myocardial protection strategies. Methods: Thirty-eight PTS undergoing myocardial revascularization were randomised into 3 groups in whom procedure was performed with intermittent cross-clamp (Group I; na 13), beating-heart on pump without aortic cross-clamp (Group II; na 12), beating-heart without use of extracorporeal circulation (Group III; na 13). Serial venous blood samples were collected for TnT measurement prior surgery, 1, 4, 12, 24, 48, 72 h after the procedure. Haemodynamic measurements were made using a thermodilution PA catheter. Results: The groups were similar with respect to age, sex, preoperative LV function, number of grafts, potential risk factors. There were no hospital deaths and no myocardial infarction (MI) in three groups, postoperative haemodynamic measurements showed no significant differences. TnT serum levels were significantly higher in group I when compared to groups II and III. TnT levels were significantly lower in group III when compared to group II following 48-h post-operation. Conclusions: Coronary bypass grafting without aortic crossclamping and without CPB offers superior myocardial protection. q 1999 Elsevier Science B.V. All rights reserved.