Importance of intraoperative transesophageal echocardiography during coronary artery surgery without cardiopulmonary bypass

The goal of this study was to assess left ventricular segmental wall motion (SWM) abnormalities during coronary artery bypass grafting (CABG) without cardiopulmonary bypass (CPB), and its impact on the immediate postoperative outcome. Transesophageal echocardiography was used intraoperatively in 27 patients (mean age 57 years) who had CABG without CPB. Images obtained with a 5-MHz biplane transesophageal echocardiographic probe in the transgastric and transesophageal planes were recorded before, during, and after 48 coronary artery clampings for saphenous vein or internal mammary artery anastomosis. Transthoracic echocardiography was performed 1 day before surgery and on the seventh postoperative day. During the 48 coronary artery clampings, 31 (64%) new SWM abnormalities were found. At the time of chest closure, complete recovery occurred in 16 (50%) segments, partial recovery in 10 (33%), and no recovery in 5 (17%). On the seventh postoperative day the new SWM abnormalities persisted in all 5 segments without recovery at the end of the surgery and in 2 of 10 (20%)segments with partial recovery (group 1). Group 1 had higher variation on the echocardiographic point score index between the beginning and end of surgery, higher enzymatic levels, more ST-T changes on the electrocardiogram, and more clinical problems than group 2 (patients without new SWM abnormalities on the seventh postoperative day) (P < .05). We concluded that new SWM abnormalities of the left ventricle occur during CABG without CPB as assessed by intraoperative transesophageal echocardiography. Persistence of these abnormalities at the end of surgery may be a predictor of SWM dysfunction and clinical problems in the immediate postoperative period.     

Randomized trial of a home-based family intervention for children who have deliberately poisoned themselves

OBJECTIVE: Intraoperative myocardial contrast echocardiography was used to determine whether the identification of regional myocardial flow patterns during revascularization could predict myocardial contractile function immediately after separation from cardiopulmonary bypass (CPB) and at 1 month after coronary artery bypass grafting (CABG) surgery. DESIGN: A prospective, open-labeled, longitudinal analysis. SETTING: Two independent university hospitals. PARTICIPANTS: Twenty patients, during and up to 1 month after CABG. INTERVENTIONS: The contrast agent Albunex (Mallenckrodt Medical, Inc, St Louis, MO) was injected into the aortic root during CPB. MEASUREMENTS AND MAIN RESULTS: Myocardial contrast echocardiography opacification of flow was graded from intraoperative transesophageal echocardiographic images of the left ventricle in the short-axis, midpapillary view. The same myocardial images were also evaluated for regional wall motion abnormalities at 15, 30, and 60 minutes, 24 hours, 5 to 8 days, and 1 month after CPB. Logistic regression analysis was used to analyze the flow scores and regional function data from identical segments. Regional flow represented by contrast enhancement was assessed in 70% of the myocardial regions (55 of 80 possible segments; 95% confidence interval [CI], 61 to 76). Flow was more easily evaluated in the posterior region (95%) than in the anterior (70%) or septal regions (60%), and least likely evaluated in the lateral regions (50%). Regional wall motion was scored in 84% of the myocardial regions (469 of 560 possible regions). Function (segmental wall motion) was assessed in all regions with equal success. Segmental function and flow scores were matched to the same regions 66% of the time (53 of 80 possible series; 95% CI, 55 to 76). Regional myocardial contrast flow patterns did not predict myocardial function at 15, 30, or 60 minutes after separation from CPB. However, contrast opacification of flow did predict regional myocardial function at 1 week (p < or = 0.05) and at 1 month (p < or = 0.01) after CABG surgery. The probability that myocardial function would be normal at 1 month was 0.62 when intraoperative flow opacification was abnormal and 0.98 when flow opacification was normal. For patients with normal flow, the estimated odds of having normal myocardial function were 3.33 times those of patients with abnormal flow at 1 week (odds ratio, 3.33; 95% CI, 1.09 to 10.19) and 18.5 times those of patients with abnormal flow at 1 month (95% CI, 2.44 to 140.48). CONCLUSION: Intraoperative application of myocardial contrast echocardiography to determine regional flow patterns after revascularization may help differentiate conditions of left ventricular systolic dysfunction immediately after separation from CPB for CABG surgery and appear to predict myocardial function at 1 month.     

Crystalloid cardioplegia route of delivery and cardiac troponin I release

BACKGROUND: Cardiac troponin I (CTn I) has been shown to be a marker of myocardial injury. Incomplete distribution of cardioplegic solution may be responsible for injury in jeopardized myocardial areas. The aim of this study was to compare CTn I release with respect to the route of delivery of crystalloid cardioplegia, either antegrade only or initially antegrade followed by retrograde cardioplegia for the remainder of the operation, in patients undergoing elective coronary artery bypass grafting. METHODS: Sixty patients were randomly assigned to one of two cardioplegia groups. Cardiac troponin I concentrations were measured in serial venous blood samples drawn just before cardiopulmonary bypass and after aortic unclamping at 6, 9, 12, and 24 hours and daily thereafter for 5 days. Analysis of variance with repeated measures was performed to test the effect of route of delivery, coronary disease, collateral circulation, risk of cardioplegia maldistribution, and number of grafts on release of CTn I. RESULTS: Compared with the antegrade route, the combined route offered no advantage in an unselected group of patients undergoing an elective first cardiac operation and having preserved left ventricular function. The CTn I concentration did not differ between groups for any of the samples considered. In patients with major left main coronary artery stenosis, CTn I release was significantly higher at hour 9 in the antegrade group than in the group with combined delivery. CONCLUSIONS: A combined route of delivery of crystalloid cardioplegia is beneficial in patients with major stenosis of the left main coronary artery. Cardiac troponin I sensitivity is relevant in this study. Release of CTn I should be useful in determining the best form of myocardial protection for each patient.     

Clinical aspects of tuberculosis in the upper aero-digestive tract

To study the effect of cardioprotection type on haemolysis, 100 patients scheduled for elective coronary artery bypass grafting were allocated to receive either blood cardioplegia (BCP) or crystalloid cardioplegia (CCP). Haemoglobin concentrations in plasma and urine were measured after induction of anaesthesia, 1 hour postoperatively and the next morning; blood acid-base status was determined at the end of cardiopulmonary perfusion; serum electrolytes and creatinine were measured before and 1 and 3 hours after the operation and serum creatinine also the next morning. Plasma haemoglobin values tended to be higher in the CCP than in the BCP group (47.6, 200.2 and 69.1 vs 31.5, 207.5 and 39.2 mg/l, p = 0.084). The urinary haemoglobin concentrations did not differ between the groups. The acid-base status showed greater buffer capacity with BCP technique. These results contradict association of blood cardioplegia technique with increased haemolysis during coronary artery bypass grafting.     

Crystalloid versus cold blood cardioplegia and cardiac troponin I release

BACKGROUND: Cardiac troponin I (CTnI) has been shown to be a marker of myocardial injury. The aim of this study was to compare antegrade crystalloid cardioplegia with antegrade cold blood cardioplegia with warm reperfusion using CTnI release as the criteria for evaluating the adequacy of myocardial protection. METHODS AND RESULTS: Seventy patients were randomly assigned to receive crystalloid or blood cardioplegia. CTnI concentrations were measured in serial venous blood samples drawn just before cardiopulmonary bypass and after aortic unclamping at 6, 9, 12, and 24 hours and daily thereafter for 5 days. ANOVA with repeated measures was performed to test the effect of the type of cardioplegia on CTnI release. The total amount of CTnI released was higher in the crystalloid cardioplegia group than in the blood cardioplegia group (11.2 +/- 8.9 versus 7.8 +/- 8.6 micrograms, P < .02). CTnI concentration was significantly higher in the crystalloid group than in the blood group in the samples drawn at hours 9 and 12. Three patients in each group had ECG evidence of perioperative myocardial infarction. Eight patients in the crystalloid group and five patients in the blood group had CTnI evidence of perioperative myocardial infarction. CTnI release was significantly lower in patients requiring no electrical defibrillation after aortic unclamping. CONCLUSIONS: Cold blood cardioplegia followed by warm reperfusion is beneficial in an unselected group of patients with a preserved left ventricular function undergoing an elective first coronary artery bypass grafting. CTnI allowed the diagnosis of small perioperative necrotic myocardial areas. The need for electrical defibrillation after aortic unclamping was related to a higher release of CTnI. A further study is necessary to determine whether this technique was beneficial because of cold blood cardioplegia, warm reperfusion, or both.     

Coronary collateral circulation behaviour and myocardial viability in chronic total occlusion treated with coronary angioplasty

AIMS: We explored the role of microcirculation integrity following the chronic occlusion of an infarct-related artery to assess the behaviour of collateral circulation during and after reperfusion by coronary angioplasty METHODS AND RESULTS: Eighteen patients with a proximally occluded left anterior descending artery and firm evidence of intercoronary collateral circulation were studied with selective coronary angiography and selective intracoronary myocardial contrast echocardiography, before coronary angioplasty, and at 5 and 15 min and 12 h later. Myocardial enhancement during myocardial contrast echocardiography was evaluated with a semiquantitative score (0-3), which was correlated to basal and 6 months' regional left ventricular wall motion results. 16/18 procedures were successfully performed; four patients with an inadequate acoustic window were excluded. Restenosis was evident at the 6 months' follow-up in two patients. Basal myocardial contrast echocardiography indicated that 81/192 segments from the left anterior descending coronary artery and 90/192 from the right coronary artery were perfused; no perfusion was observed in 21 segments either before or after coronary angioplasty. After coronary angioplasty, the angiographic intercoronary collateral circulation immediately disappeared, and myocardial contrast echocardiography revealed that there was a progressive reduction of segments perfused by the right coronary artery and an increase in segments perfused by the left anterior descending coronary artery. Regional left ventricular wall motion analysis demonstrated that there was abnormal motion in 51/192 segments. There was no improvement in segments with score 0 and abnormal motion after 6 months (100% sensitivity), but 16/17 segments with score 3 did show an improvement (98% specificity). The predictive value of intermediate scores (1-2) in detecting long-term improvement, was only 43%. CONCLUSION: These data show that the adaptive mechanism observed in the behaviour of epicardial and microvascular circulation after reperfusion of a chronic occluded infarct-related artery can vary. In addition, this study clearly shows that microvascular integrity detected by myocardial contrast echocardiography can provide myocardial viability.     

Clinical experience with continuous warm blood cardioplegia

We applied the Continuous Warm Blood Cardioplegia (CWBC) as an approach to improve myocardial preservation. From March to June in 1992, we used the CWBC in six patients and the conventional cold crystalloid cardioplegia (CCCP) in seven patients. All of them underwent isolated coronary artery bypass grafting. There was no marked difference between the CWBC and CCCP in post operative serum level of creatine kinase (MB type), cardiac output and dose of dopamine during they weaned from cardiopulmonary bypass. All patients treated with CWBC spontaneously restored the normal sinus rhythm shortly after removal of the aortic crossclamp, which was distinct from the fact that the CCCP group showed no such recovery. This result suggest that CWBC kept high-energy phosphate level without disturbing production of ATP in myocardium. Furthermore, reperfusion injury was also likely to be prevented by CWBC.     

Evaluation of myocardial protection with DBcAMP in crystalloid cardioplegic solutions

The potential for myocardial protection during cardiac operation was evaluated by adding Dibutyryl cyclic AMP (DBcAMP) to the crystalloid cardioplegic solutions. We have compared the cold crystalloid cardioplegia with DBcAMP (Group D n = 15) and without DBcAMP (Group n = 20) in patients undergoing cardiac operation. In hemodynamics, both groups were no difference before and after operation. CPK and CPK-MB was significantly (p < 0.01) high level after cardiopulmonary bypass (CPB) in group C. Myoglobin was also high value after CBP in group C, but not significant. Myocardial oxygen extraction rate and coronary blood PCO2 release were similar change in both groups. Insulin/glucose ratio was high level during and after CBP in group D. Myocardial lactate/pyruvate ratio was very high level after CBP in group C without significant difference. We consider that the cardioplegic solution with DBcAMP is effectual for the myocardial metabolism and preservation of myocardial damage during cardiac arrest.     

G1 accumulation caused by iron deprivation with deferoxamine does not accompany change of pRB status in ML-1 cells

In hypertension, several factors disturb coronary circulation and the metabolic reserve of the heart. This study was undertaken to test whether in hypertensive patients global and regional left ventricular (LV) function is related during exercise to the presence of significant coronary stenosis and whether lowering of coronary perfusion pressure through rapid normalization of the diastolic pressure may modify the dynamics of the left ventricle. Thirty-five patients with mild to moderate hypertension undergoing coronary angiography for the evaluation of chest pain were included in the study; upright bicycle exercise echocardiography tests were performed without therapy and 1 day later 1 h after sublingual administration of nifedipine. LV ejection fraction and regional wall motion scores were evaluated and compared at baseline, peak exercise, immediate postexercise, and recovery phases in each test through digital on-line storing of echocardiographic images. Twenty-one patients had normal coronary arteries (group 1) and 14 significant coronary stenoses (group 2); age, gender, heart rate, blood pressure, left ventricular diameter and mass index, and ejection fraction were similar in the two groups. At peak exercise LV ejection fraction slightly increased in group 1, whereas it slightly decreased in group 2 (both during the test without therapy and after nifedipine administration). All patients in group 1 had normal left ventricular wall motion during exercise; 13 of 14 patients in group 2 had LV wall motion abnormalities at peak exercise. Nifedipine did not produce any effect on LV regional wall motion in group 1, but it induced significant changes in LV regional wall motion in seven patients in group 2. Changes in LV wall motion between the two test groups were related to the number of the stenotic coronary vessels: the normal exercise test before and after therapy and the two normalized tests after nifedipine administration were in fact observed in patients with one-vessel disease, whereas worsening or changes in the site of ischemia were observed only in patients with multivessel disease. Regional and global left ventricular dynamics during exercise is mainly dependent on the existence of significant coronary artery disease. Rapid decrease of blood pressure does not alter the regional dynamics of the left ventricle during exercise in patients without coronary artery disease, but it may induce normalization, worsening, or changes in the site of wall motion abnormalities in hypertensives with significant coronary stenoses.     

A study of the 30 minutes following reperfusion after crystalloid and cold blood cardioplegia by enzymatic and metabolic analysis of coronary blood flow

Post-ischemic reperfusion phenomena were studied in two methods of myocardial protection: crystalloid cardioplegia (St Thomas n(o) 2) and cold blood cardioplegia (Buckherg) during cardiopulmonary bypass for human myocardial revascularisation. Myocardial protection was assessed on the course of hemodynamic parameters, reperfusion arrhythmias and biochemical analysis of the coronary flow after cross-clamp removal: creatine phosphokinase (CPK-MB) and nucleotide adenine metabolites (adenosine, inosine, hypoxanthine, xanthine and uric acid). The study was performed in two groups of 14 patients. Hemodynamic conditions were similar in both groups during reperfusion in order to avoid different coronary flow. Under these conditions, myocardial protection by cold blood cardioplegia reduced reperfusion arrhythmias, and resulted in a loss of CPK-MB release. Furthermore, cold blood cardioplegia provided protection of myocardial energy metabolism by reducing the loss of metabolites, purine bases and oxypurine bases into the coronary sinus. Our results also show that hypoxanthine is probably the final product of ATP degradation in human myocardial tissue.     

Differential regulation of vitamin D receptors in clonal populations of a chronic myelogenous leukemia cell line

BACKGROUND: Both crystalloid and blood cardioplegia result in cardiac dysfunction associated with myocardial edema. This edema is partially due to the lack of myocardial contraction during cardioplegia, which stops myocardial lymph flow. As an alternative, acceptable surgical conditions have been created in patients undergoing coronary artery bypass operations with esmolol-induced minimal myocardial contraction. We hypothesized that minimal myocardial contraction during circulatory support using either standard cardiopulmonary bypass (CPB) or a biventricular assist device would prevent myocardial edema by maintaining cardiac lymphatic function and thus prevent cardiac dysfunction. METHODS: We placed 6 dogs on CPB and 6 dogs on a biventricular assist device and serially measured myocardial lymph flow rate and myocardial water content in both groups and preload recruitable stroke work only in the CPB dogs. In all dogs we minimized heart rate with esmolol for 1 hour during total circulatory support. RESULTS: Although myocardial lymph flow remained at baseline level during CPB and increased during biventricular assistance, myocardial water accumulation still occurred during circulatory support. However, as edema resolved rapidly after separation from circulatory support, myocardial water content was only slightly increased after CPB and biventricular assistance, and preload recruitable stroke work was normal. CONCLUSIONS: Our data suggest that minimal myocardial contraction during both CPB and biventricular assistance supports myocardial lymphatic function, resulting in minimal myocardial edema formation associated with normal left ventricular performance after circulatory support. The concept of minimal myocardial contraction may be a useful alternative for myocardial protection, especially in high-risk patients with compromised left ventricular function.     

Intraoperative transesophageal echocardiography for detection of myocardial ischemia

Preoperative myocardial ischemia seems to be a predictor of poor outcome when detected by electrocardiography, pulmonary capillary wedge/pressure measurement and echocardiography. It could be demonstrated, that regional wall motion abnormalities appear earlier and are more sensitive signs of myocardial ischemia than the ECG. Using intraoperative epicardial and transesophageal echocardiography, high quality 2-d echocardiographic images of the heart can be recorded. For monitoring of left ventricular function and wall motion the transesophageal approach is most often used. By the transesophageal approach the left ventricle can be scanned in the long axis and by the transgastric approach in cross sections. They correspond to the apical four-chamber and left parasternal cross sectional imaging of the heart. Using the transgastric approach in the papillary short axis view all segments representing the three coronary arteries can be imaged. Recording in this position have been found to be highly reproducible. Only localized ischemia of the apex of the ventricle may be missed. Methologically the rotation and translocation of the heart remain a problem using the cross section images of the heart. But the left ventricular papillary muscles and the septal-right ventricular boarders can be used as land marks. Wall motion is scored in five grades. In addition to the semiquantitative analysis also a quantitative calculation using computers is possible. Using the midd papillary short axis view in nearly 120 intraoperative transesophageal echocardiograms since 1989 analysis of the systolic wall thickening was possible in 73% of the patients. According to the literature review 87% of the patients undergoing coronary bypass surgery or non-cardiac surgery have signs of preoperative ischemia.(ABSTRACT TRUNCATED AT 250 WORDS)     

The internal thoracic artery of poor quality: was cardiac massage a cause of ITA stenosis?

The case of stenotic left internal thoracic artery (LITA), with a very rare and interesting histological findings is reported. The patient, a 65-year-old man, fell into shock, due to acute myocardial infarction and received cardiopulmonary resuscitation at home immediately. Three months later, patient underwent coronary artery bypass grafting. The LITA was dissected from the chest wall with a tissue pedicle by usual manner. However, it was abandoned to use for grafting, because of extremely poor blood flow even after balloon dilatation was noticed. Histological study revealed a significant granulation of LITA media, led to severe stenosis of LITA lumen on it's portion. On other side, either proximal and distal portion of LITA remained intact. It seems that this unusual histological change of LITA media developed after LITA over stretching due to cardiac massage during cardiopulmonary resuscitation. If patient, scheduled for coronary bypass surgery, has in a personal history the presence of cardiac massage, traffic accident, some contact sport or any other chest trauma, it is recommended to perform LITA angiography preoperatively, if an intention to use the LITA for coronary artery bypass grafting exists.     

Lidocaine cardioplegia for prevention of reperfusion ventricular fibrillation

Lidocaine addition to crystalloid cardioplegic solution for prevention of reperfusion ventricular fibrillation after the release of the aortic cross-clamp was studied in 50 patients undergoing coronary artery bypass grafting and in 30 patients undergoing mitral or aortic valve replacement. Twenty-six of the patients undergoing coronary artery bypass grafting received lidocaine, 100 mg/L of cardioplegia, whereas a control group of 24 patients received cardioplegia without lidocaine. In the group undergoing valve replacement, 14 patients received lidocaine cardioplegia and 16 patients served as control. In the coronary artery bypass grafting group, lidocaine cardioplegia reduced significantly the incidence of reperfusion ventricular fibrillation from 100% to 42%. In the valve group, lidocaine cardioplegia also reduced significantly the incidence of reperfusion ventricular fibrillation from 93% to 42%. In both groups, lidocaine cardioplegia decreased the number of direct-current countershocks required to defibrillate the heart, with no significant increase in the incidence of high-grade atrioventricular block.     

Lipopolysaccharide activation of murine splenocytes and splenic B cells increased the expression of aryl hydrocarbon receptor and aryl hydrocarbon receptor nuclear translocator

BACKGROUND: To achieve complete myocardial revascularization in patients with diffuse coronary artery disease and patients at high risk if they undergo cardiopulmonary bypass such as severe systemic disease or diffuse arteriosclerosis of the aorta, we have adopted the technique of combining direct coronary artery bypass grafting without cardiopulmonary bypass with transmyocardial laser revascularization. METHODS: From April 1995 to September 1997 this technique was used in 77 patients. Ages ranged from 37 to 85 years with a mean of 56 +/- 17 years. Diffuse coronary artery lesions were present in 46 patients, 10 had severely deranged renal function, 7 had diffuse carotid artery lesions, and 7 had aortic arch atheromas. Liver dysfunction was present in 4 patients and severe obstructive airway disease in 3. The mean left ventricular ejection fraction was 0.45 +/- 0.05. Midsternotomy approach was used in 65 patients and anterior minithoracotomy in 12. Direct coronary artery bypass grafting without cardiopulmonary bypass was done to the left anterior descending coronary artery or right coronary artery or both. Transmyocardial laser revascularization using a 1,000-W CO2 laser machine was performed on the areas supplied by ungraftable coronary arteries or even in graftable distal targets in the posterolateral or inferior wall in patients who were at high risk if they underwent cardiopulmonary bypass. RESULTS: The mean number of vessels bypassed was 1.12. One patient died of intractable ventricular arrhythmia in the early postoperative phase. Mean follow-up was 16.6 months. At 12 months 89% of the patients were angina free. Metabolic stress test demonstrated an average increase in exercise tolerance from 5.2 at baseline to 9.7 minutes at 12 months. Myocardial thallium scanning done at 3-, 6-, and 12-month intervals postoperatively revealed that myocardial perfusion in grafted segments had an exponential trend of improvement, and perfusion in transmyocardial laser revascularization segments showed a linear trend in the same period with a total gain of 28.4%. CONCLUSIONS: Transmyocardial laser revascularization is an excellent adjunct to minimally invasive coronary artery bypass grafting to achieve complete myocardial revascularization in patients with graftable vessels in the anterior wall and ungraftable vessels in the posterior and inferior wall. This achieves complete myocardial revascularization without compromising safety in patients who are at high risk if they undergo cardiopulmonary bypass. Minimal morbidity and mortality in the present series revealed that this procedure is safe, and postoperative follow-up of these patients showed significant functional improvement as well as an improvement in myocardial perfusion scan.     

Quantitative analysis of stool losses in adult celiac disease: use of near-infrared analysis reconsidered

Reoperative coronary artery bypass grafting (CABG) are still associated with higher mortality than primary CABG. This is due in part to the potential for cardiac and patent graft injury during their dissection and the reopening of the sternum. Therefore, in two patients with recurrent angina attributable to occlusion of the old vein graft to the LAD, we performed reoperative CABG by the minimally invasive direct coronary artery bypass (MIDCAB) procedures. The left internal thoracic artery was anastomosed to the LAD through small anterolateral thoracotomy without cardiopulmonary bypass. Both patients recovered fast and underwent postoperative angiogram, showing the new grafts widely patent. About two weeks later, both discharged in the conditions of nearly normal activities. The reoperative MIDCAB grafting might be expected to be as safe and promising as the primary one.     

Diagnostic localization of insulinoma. Experiences with 25 patients with solitary tumors

A 71-year old man presented with partial rupture progressing to complete rupture of the left ventricular anterior papillary muscle after acute anterolateral myocardial infarction. The progressive rupture was demonstrated by transthoracic and transesophageal echocardiography. Transthoracic echocardiography showed exaggerated systolic prolapse of the anterior mitral leaflet with grade III mitral regurgitation and partial disruption of the anterolateral papillary muscle, but transesophageal echocardiography during surgery disclosed the progression of the partial rupture to complete rupture. The flail anterior mitral leaflet with severe mitral regurgitation and the head of the ruptured papillary muscle into the left atrium in systole were confirmed. The patient was treated by coronary artery bypass grafting and mitral valve prosthesis using a St. Jude Medical valve with good outcome.     

Myocardial damage after minimally invasive coronary artery bypass grafting on the beating heart

BACKGROUND: In conventional coronary artery bypass grafting, the rate of perioperative myocardial infarction is reported in the 2% to 6% range; however, significantly higher rates are observed if sensitive myocardial marker proteins are used to detect perioperative myocardial damage. For minimally invasive direct coronary artery bypass grafting, few data are available concerning myocardial marker protein release. METHODS: Fifteen consecutive patients (11 male, 4 female; mean age, 59.6 +/- 8.5 years) received minimally invasive direct coronary artery bypass grafting procedures via minithoracotomy on the beating heart. Electrocardiography and transesophageal and transthoracic echocardiography as well as determination of creatine kinase-MB mass concentration and cardiac troponin I level were used for ischemic monitoring. RESULTS: One patient had a perioperative myocardial infarction according to standard criteria and died despite mechanical circulatory support. Determination of cardiac troponin I level showed small but definitive ischemic damage in 4 of 9 patients (44%) who presented transient ischemic signs intraoperatively or postoperatively. In 2 of these 4 patients pathologic findings could be detected on angiographic restudies. CONCLUSIONS: Subclinical myocardial injury is a common event in minimally invasive coronary artery bypass grafting on the beating heart. Cardiac troponin I could serve as an adequate diagnostic tool for diagnosis of perioperative myocardial infarction in minimally invasive direct coronary artery bypass grafting.     

Duplication and distribution of repetitive elements and non-unique regions in the human genome

The natural history of patients with coronary artery disease and diastolic dysfunction who underwent coronary artery bypass grafting (CABG) is not well known. The aims of our study were to evaluate the incidence of diastolic dysfunction, its evolution after CABG and its possible correlation with adverse in-ICU prognosis. We studied 88 consecutive patients scheduled for CABG with not severely depressed left ventricular function (ejection fraction > 35%) and multivessels disease. Buckberg cardioplegia was used for myocardial protection. Diastolic function was investigated by recording mitral and venous pulmonary flow by transesophageal Doppler echocardiography (TEE). TEE examination was performed in operative room pre and post-bypass, at ICU arrival and after three months. Diastolic dysfunction was defined as mild, moderate and severe. Adverse in ICU events were defined as: use of inotropic drugs or ventricular mechanical support, an ICU stay > 24 hours, perioperative myocardial infarction and death. The study group was compared with a control group. T-Student test was used; a p < 0.05 was considered significant. A reduced diastolic function was present in 77% of patients at baseline examination. Diastolic dysfunction did not worsen significantly after hypothermic cardiac arrest and reperfusion. It persisted during ICU stay and normalized after three months from CABG in the majority of patients (85%). Diastolic failure was not associated with an adverse ICU prognosis (adverse events: 18 versus 13%; p = ns).     

Molecular cloning of cDNA for pro-phenol-oxidase-activating factor I, a serine protease is induced by lipopolysaccharide or 1,3-beta-glucan in coleopteran insect, Holotrichia diomphalia larvae

BACKGROUND: To evaluate the effects of minimally diluted tepid blood cardioplegia, a prospective, randomized study was undertaken. METHODS: Thirty-seven patients undergoing isolated primary coronary artery bypass grafting were randomized to receive standard 4:1 diluted tepid blood cardioplegia (4:1 group, n = 18) or minimally diluted tepid blood cardioplegia (Mini group, n = 19). Cardioplegic solution was delivered in an intermittent antegrade fashion in both groups. Myocardial oxygen and lactate metabolism, release of the MB isoenzyme of creatine kinase and thiobarbituric acid reactive substances, and cardiac function were measured during and after the operation. RESULTS: Myocardial oxygen consumption was significantly greater and lactate release was significantly lower in the Mini group than in the 4:1 group during cardioplegia. Minimally diluted blood cardioplegia resulted in more prompt resumption of lactate extraction, lower levels of release of the myocardial-specific isoenzyme of creatine kinase and thiobarbituric acid reactive substances during reperfusion, and better postoperative left ventricular function compared with the standard 4:1 cardioplegia. CONCLUSIONS: Minimally diluted tepid blood cardioplegia may provide superior myocardial protection than the standard 4:1 dilution technique by optimizing the aerobic environment through an increase in oxygen supply during intermittent cardioplegia.