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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.

There is no strong evidence supporting the use of preoperative intra-aortic balloon pump (IABP) in high-risk patients undergoing coronary artery bypass grafting (CABG). This issue has only been investigated in small studies which analysed the general population of patients, without focusing on specific subgroups, including gender.We sought to determine if there is any benefit from preoperative IABP in high-risk patients undergoing CABG with the analysis of its determinants including gender.We randomly assigned 502 high-risk patients (351 men, 151 women) to the group receiving preoperative IABP support or to the control group with no preoperative IABP. Primary end-point was a major adverse cardiac or cerebrovascular event (MACCE), defined as death from any cause, myocardial infarction, cerebrovascular accident or repeat revascularisation within 30 days post-surgery.A significant reduction of MACCE rate in patients with the preoperative IABP counterpulsation in comparison to controls was noticed in the total population of high risk patients (p=0.001) and in the female subgroup (p=0.005). After adjustment for baseline characteristics, the hazard ratio for MACCE was 0.7 (p=0.005) in the total population; 0.6 (p=0.01) for females and 0.8 (p=0.1) for males.There is a beneficial effect of preoperative IABP use in high-risk patients undergoing CABG, particularly in women and patients with co-morbidities (diabetes, obesity, and peripheral vascular disease).

Systolic dyssynchrony as an indication for cardiac re-synchronization therapy is present in a considerable subset of patients with congestive heart failure undergoing surgical coronary revascularisation. Coronary artery bypass grafting offers an optimal setting for totally epicardial cardiac re-synchronization system implantation.To assess the feasibility and safety of totally epicardial cardiac re-synchronization system implantation in patients with ischaemic heart disease and heart failure undergoing coronary artery bypass grafting.Three male patients with coronary artery disease and postinfarction functional class III congestive heart failure underwent a combined procedure of on-pump surgical coronary revascularisation and totally epicardial cardiac re-synchronization system implantation (all three leads implanted epicardially). In all patients intraventricular dyssynchrony was revealed in preoperative echocardiography.There was no perioperative morbidity or mortality. The mean total time required for cardiac re-synchronization system implantation was 17.3+/-2.3 minutes. We obtained excellent pacing and sensing parameters at implant (left ventricular pacing thresholds: 0.8, 0.5, 0.5 V at 0.5 ms; left ventricular sensing thresholds: 17, 15, 20 mV, respectively in consecutive patients). After 12 months pacing and sensing parameters remained stable. Significant improvement in 6-minute walk test distance, functional class and echocardiographic parameters (left ventricular ejection fraction, intraventricular dyssynchrony) was observed in all patients.Totally epicardial cardiac re-synchronization system implantation is safe and can be regarded as an important supplement to surgical coronary revascularisation in the still growing population of patients with severe heart failure and systolic dyssynchrony, which can be used for the optimisation of treatment results.

Warm myocardial protection has had a strong impact on modern cardiac surgery. The O2 consumption of a heart, arrested by potassium-enriched normothermic blood is 90% less than baseline values. Hypothermia gives only a slight reduction in oxygene consumption.was to test the quality of myocardial protection provided by intermittent antegrade warm blood cardioplegia (IAWBC) by comparing it with cold blood cardioplegia.We designed a prospective randomized study by using 2 different temperatures of blood cardioplegia: warm, from 35 degrees C to 37 degrees C (group I--36 men and 14 women, mean age 56 +/- 7); and cold, from 6 degrees C to 8 degrees C (group II--40 men and 10 women, mean age 58 +/- 9). Cardiac troponin I release was the criterion used to evaluate the adequacy of myocardial protection,The heartbeat in 92% of patients treated with warm cardioplegia converted to normal sinus rhythm spontaneously after removal of the aortic crossclamp compared with only 18% of the cold cardioplegia group. Cardiac troponin I concentration was significantly higher in the cold group. Our study demonstrates a significant reduction of myocardial cell damage with the use of IAWBC.Our clinical results have shown that IAWBC is a superior method compared to intermittent cold cardioplegia.

Cardiovascular diseases are one of the most common causes of hospitalization. Renal failure is a very important risk factor in patients undergoing heart surgery. So far few authors have written about non-dialysis dependent patients with mild renal insufficiency undergoing heart surgery. The purpose of this study is to present most important risk factors and outcomes in patients with different stages of renal insufficiency. The authors have studied attentively non-dialysis dependent patients with mild renal insufficiency because of high risk of pooperative renal failure in this population. To diminish high risk of perioperative death in these patients, there is a need for very close co-operation between cardiologists, cardiac surgeons and nephrologists.

The aim of the study was to analyze perioperative risk factors, with special attention to cardioprotective techniques. Additionally we compared effectiveness of standard risk scales (Cleveland and Canadian) and own risk scale (modified by inclusion Graham, Chambers, Davies classification of distal coronary arteries) in investigated group. The obtained data indicate that cardioprotective techniques have no impact on clinical results but there are some important factors which influence surgical treatment: age (over 75 years), ejection fraction less than 20% and poor distal parts of coronary vessels. The regression model results were used to calculate predictive value of Cleveland or Canadian risk scale (measured area under ROC curve). Effectiveness of anticipation: mortality (Cleveland and Canadian), complications, ICU and hospital stay in patients with severely depressed left ventricular function achieved 71%, 70%, 70%, 71%, 69%, respectively. After including Graham, Chambers, Davies classification of distal coronary arteries predictive value improved 3-4% and thereby raised to 74%, 73%, 74%, 74% and 72%.

This article provides a biomechanical analysis of the distribution of force in wire sutures used for sternal closure in cardiothoracic surgery.The parameters we measured included displacement in the elastic region, plastic limit, and rupture load on the closure. Force distribution analysis was carried out for every kind of wire suture. A linear regression line of displacement as a function of increasing load was determined for each closure method.Straight wire had less displacement at each load, figure-8 had medium, and interlocking multitwisted (IM) had the most displacement within the elastic range of the specimen. The differences between straight and interlocking multitwisted sutures were statistically significant. When the plastic limit was compared between straight and interlocking multitwisted closure, the differences were statistically significant. In the straight suture the forces used to approximate the sternal halves are perpendicular to the incision. With the figure-8 and interlocking multitwisted suture, the forces are dispersed and the effective approximation force is lower than that applied to the wires.Straight wires provide good fixation stability for the durability of the sternum, and the somewhat lower strength could be compensated by increasing the number of sutures. The figure-8 and IM have better strength and are less likely to cut the sternum because of advantageous redistribution of shearing forces of the wire as compared to straight closures.