Improvement of refractory pruritus after lipoprotein-apheresis in arthrogryposis-renal failure-cholestasis syndrome.

Accumulation of bile acids can lead to invalidating pruritus in cholestatic patients. Few reports exist on the influence of lipoprotein-apheresis (LA) on plasma level of total bile acids (tBA). We report of significant decrease in tBA levels and drastic improvement of pruritus in a 5-year-old girl with arthrogryposis-renal failure-cholestasis syndrome. We present LA as a suitable rescue treatment option in therapy-refractory cholestasis-associated pruritus, at least as bridge until a long-term solution such as entero-biliary anastomosis or transplantation is possible.

Istaroxime treatment ameliorates calcium dysregulation in a zebrafish model of phospholamban R14del cardiomyopathy.

The heterozygous Phospholamban p.Arg14del mutation is found in patients with dilated or arrhythmogenic cardiomyopathy. This mutation triggers cardiac contractile dysfunction and arrhythmogenesis by affecting intracellular Ca2+ dynamics. Little is known about the physiological processes preceding induced cardiomyopathy, which is characterized by sub-epicardial accumulation of fibrofatty tissue, and a specific drug treatment is currently lacking. Here, we address these issues using a knock-in Phospholamban p.Arg14del zebrafish model. Hearts from adult zebrafish with this mutation display age-related remodeling with sub-epicardial inflammation and fibrosis. Echocardiography reveals contractile variations before overt structural changes occur, which correlates at the cellular level with action potential duration alternans. These functional alterations are preceded by diminished Ca2+ transient amplitudes in embryonic hearts as well as an increase in diastolic Ca2+ level, slower Ca2+ transient decay and longer Ca2+ transients in cells of adult hearts. We find that istaroxime treatment ameliorates the in vivo Ca2+ dysregulation, rescues the cellular action potential duration alternans, while it improves cardiac relaxation. Thus, we present insight into the pathophysiology of Phospholamban p.Arg14del cardiomyopathy.

Chemical interactions between Saturn's atmosphere and its rings.

The Pioneer and Voyager spacecraft made close-up measurements of Saturn's ionosphere and upper atmosphere in the 1970s and 1980s that suggested a chemical interaction between the rings and atmosphere. Exploring this interaction provides information on ring composition and the influence on Saturn's atmosphere from infalling material. The Cassini Ion Neutral Mass Spectrometer sampled in situ the region between the D ring and Saturn during the spacecraft's Grand Finale phase. We used these measurements to characterize the atmospheric structure and material influx from the rings. The atmospheric He/H2 ratio is 10 to 16%. Volatile compounds from the rings (methane; carbon monoxide and/or molecular nitrogen), as well as larger organic-bearing grains, are flowing inward at a rate of 4800 to 45,000 kilograms per second.

Blood warm reperfusion: a necessary adjunct to heart-valve surgery in low-risk patients?

AIM: The aim of this prospective, randomized study was to determine whether blood warm reperfusion improves myocardial protection provided by cold crystalloid cardioplegia in patients undergoing first-time elective heart-valve surgery, using cardiac troponin I release as the criterion for evaluating the adequacy of myocardial protection. METHODS: Seventy patients with a left ventricular ejection fraction greater than 40% were randomly assigned to 1 of 2 myocardial protection strategies: 1) cold crystalloid cardioplegia with no reperfusion or 2) cold crystalloid cardioplegia followed by 2-minute blood warm reperfusion before aortic unclamping. Cardiac troponin I concentrations were measured in serial venous blood samples drawn immediately prior to cardiopulmonary bypass and after aortic unclamping at 6, 9, 12, and 24 h. RESULTS: Randomization produced 2 equivalent groups. The total amount of cardiac troponin I released (7.17+/- 14.8 mg in the crystalloid cardioplegia with no reperfusion group and 5.82+/-4.66 mg in the crystalloid cardioplegia followed by blood warm reperfusion group) was not different (P > 0.2). Cardiac troponin I concentration did not differ for any sample in either of the 2 groups. The total amount of cardiac troponin I released was higher in patients who required inotropic support (9.14 +/-16.2 mg) than those who did not (4.73+/-4.52 mg; P = 0.009). CONCLUSIONS: Our study shows that adding blood warm reperfusion to cold crystalloid cardioplegia provides no additional myocardial protection in low-risk patients undergoing heart-valve surgery.

False lumen patency as a predictor of late outcome in aortic dissection.

Aortic dissection (AD) is a disease with a high-risk of mortality. Late deaths are often related to complications in nonoperated aortic segments. Between 1984 and 1996, we retrospectively analyzed the data of 109 patients with acute AD (81 men and 28 women; average age 61 +/- 14 years). All imaging examinations were reviewed, and a magnetic resonance imaging examination was performed at the time of the study. Aortic diameters were measured on each aortic segment. Predictive factors of mortality were determined by Cox's proportional hazard model, in univariate and multivariate analyses, using BMDP statistical software. Follow-up was an average of 44 +/- 46 months (range 24 to 164). Actuarial survival rates were 52%, 46%, and 37% at 1, 5, and 10 years, respectively, for type A AD versus 76%, 72%, and 46% for type B AD. Predictors of late mortality were age >70 years and postoperative false lumen patency of the thoracic descending aorta (RR 3.4, 95% confidence intervals 1.20 to 9.8). Descending aorta diameter was larger when false lumen was patent (31 vs 44 mm; p = 0.02) in type A AD. Furthermore, patency was less frequent in operated type A AD when surgery had been extended to the aortic arch. Thus, patency of descending aorta false lumen is responsible for progressive aortic dilation. In type A AD, open distal repair makes it possible to check the aortic arch and replace it when necessary, decreases the false lumen patency rate, and improves late survival.

Effects of myocardial ischemia on the release of cardiac troponin I in isolated rat hearts.

BACKGROUND: The twofold aim of this experimental study was (1) to verify the correlation between the duration of ischemia and concentration of cardiac troponin I and (2) to compare the release of cardiac troponin I with histologic findings. METHODS: Experiments were done on 18 rat hearts, which were perfused according to the Langendorff method, immediately after excision in group I (control group) and after immersion for 3 hours (group II) and 6 hours (group III) in St. Thomas' Hospital solution at 4 degrees C. During reperfusion, the release of cardiac troponin I, creatine kinase isoenzyme MB, and lactate dehydrogenase, the recovery of left ventricular pressure, and heart rates were compared among the three groups. After the experiment, three samples of myocardium (left ventricle, right ventricle, and septum) were taken for histologic examination. RESULTS: Cardiac troponin I concentration was significantly higher in group III than in groups I and II and in group II compared with group I. Cardiac troponin I concentration increased as the ischemic period increased. The relation between cardiac troponin I release and ischemic duration tended to be linear. Creatine kinase MB and lactate dehydrogenase concentrations did not differ from one group to the other. Left ventricular pressure was not significantly different among the groups. In the control group, no heart had more than 10% of the myocytes affected. One of six hearts in group II and three of six in group III had more than 10% of myocytes affected. CONCLUSION: This experimental study showed (1) that cardiac troponin I is an early marker of ischemic injury and (2) that cardiac troponin I concentration increases as the ischemic period increases. Early cardiac troponin I release appears to correlate with the extent of ischemic injury in rats undergoing buffer perfusion.

Intermediate lukewarm (20 degrees c) antegrade intermittent blood cardioplegia compared with cold and warm blood cardioplegia.

BACKGROUND: In the field of intermittent antegrade blood cardioplegia, 3 levels of temperature are commonly used: (1) cold (8 degrees C); (2) tepid (29 degrees C); and (3) warm (37 degrees C). Given the 21 degrees C spread and the metabolic changes that can occur between cold (8 degrees C) and tepid (29 degrees C) cardioplegia, we thought it worthwhile to test a temperature halfway between the cold and tepid levels. The aim of this study was to test the quality of myocardial protection provided by intermediate lukewarm (20 degrees C) cardioplegia by comparing it with cold and warm cardioplegia. Protection was assessed by measuring cardiac troponin I release. METHODS: One hundred thirty-five patients undergoing coronary artery bypass grafting were enrolled in a prospective randomized trial comparing cold (8 degrees C), intermediate lukewarm (20 degrees C), and warm (37 degrees C) antegrade intermittent blood cardioplegia. Cardiac troponin I concentrations were measured in serial venous blood samples. RESULTS: The total amount of cardiac troponin I released was significantly higher in the cold group (4.7 +/- 2.3 microg) than in the intermediate lukewarm (3.4 +/- 2.0 microg) or the warm (3.1 +/- 2.7 microg) groups. The cardiac troponin I concentration was significantly higher at hour 6 in the intermediate lukewarm group (1. 23 +/- 0.55 microg/L) than in the warm group (0.89 +/- 0.50 microg/L). CONCLUSIONS: Intermittent antegrade intermediate lukewarm blood cardioplegia is appropriate and clinically safe. Cardiac troponin I release suggests that intermediate lukewarm cardioplegia is better than cold cardioplegia but less effective than warm cardioplegia in low-risk patients. We therefore recommend the use of warm cardioplegia in low-risk patients.

The Y graft: myocardial revascularization with both internal thoracic arteries. Evaluation of eighty cases with coronary angiographic assessment.

The use of bilateral in situ internal thoracic arteries is restricted by the risk of sternal devascularization, the length of the pedicle, and the necessity to avoid crossing the midline. The aim of this study is to evaluate Y grafts achieved by anastomosing the proximal end of the free right internal thoracic artery to the side of the attached left internal thoracic artery. Y grafts were performed in 80 patients, aged 41 to 74 years (mean age 58.6 years) between May 1991 and September 1992. Two different techniques were used. Thirty-four patients were included in group 1 and 46 in group 2. Seventy-nine grafts were performed from the left internal thoracic artery to the left anterior descending artery. The right internal thoracic artery was anastomosed to the diagonal artery (5 times), the marginal branch (67 times), the circumflex artery (7 times) and the right coronary artery (2 times). Seventy-five complementary saphenous vein bypasses were performed in 58 patients. Operative mortality was 2.5%. Two patients had perioperative myocardial infarcts (2.5%) on nonbypassed sites. Three patients had sternal wound infections (3.7%). Sixty-two patients (80%) were reexamined by angiography at month 6-25 in group 1 and 37 in group 2. Sixty left internal thoracic artery bypass grafts (97%) were patent versus 39 right internal thoracic artery bypass grafts (63%). In group 1, 23 of 25 left internal thoracic artery bypass grafts were patient (92%) versus 12 right internal thoracic artery grafts (48%). In group 2, all 37 left internal thoracic artery bypass grafts were patent (100%) versus 27 right internal thoracic artery grafts (73%). With this procedure, particular attention must be paid to the length of the right internal thoracic artery, and extensive training is required.

Preoperative quality of life as a predictive factor of 3-year survival after open heart operations.

BACKGROUND: The aim of this prospective study was twofold: to determine the evolution of quality of life in heart surgery patients through the first 3 postoperative years using the Nottingham Health Profile questionnaire and to determine whether preoperative quality of life influences 3-year survival. METHODS: From January to July 1994, 215 patients underwent elective open heart operation in our department. Patients filled in the Nottingham Health Profile questionnaire five times: preoperatively, postoperatively at month 3, and at each anniversary of their operation for 3 years. The evolution of quality of life scores through time were compared using analysis of covariance with repeated measures. Analysis of 3-year survival prognostic factors was achieved using the Cox proportional hazards model. RESULTS: Quality of life scores varied through time, but not significantly. Multivariate analysis showed two independent risk factors to influence 3-year survival: dyspnea class (III-IV versus I-II, relative risk = 2.80, 95% confidence interval = 1.2 to 6.5) and the energy section of the Nottingham Health Profile questionnaire (relative risk = 1.02 by unit, 95% confidence interval = 1.01 to 1.03). CONCLUSIONS: Our study shows quality of life scores to be stable for the first 3 years after operation and the preoperative energy score to be predictive of 3-year survival.

Effects of L-arginine administration before cardioplegic arrest on ischemia-reperfusion injury.

BACKGROUND: Administration of L-arginine during reperfusion or its addition to cardioplegic solution has been shown to protect myocardium against ischemia-reperfusion injury. This study aimed at evaluating the role of L-arginine in ischemia-reperfusion injury when administered intraperitoneally 24 hours before cardioplegic arrest. METHODS: Two groups of Sprague-Dawley rats (control, n = 10; and L-arginine, n = 10) were studied in an isolated buffer-perfused heart model. Both groups were injected intraperitoneally 24 hours before ischemia. Before experimentation blood samples were collected for cardiac troponin I and cGMP analysis. In the coronary effluents, cardiac troponin I, adenosine, cyclic guanosine monophosphate, and nitric oxide metabolites were assayed. RESULTS: Before heart excision, serum cardiac troponin I concentrations were higher in the L-arginine than in the control group (0.037 +/- 0.01 versus 0.02 +/- 0.05 microg x L(-1); p < 0.05). During reperfusion, cardiac troponin I release was lower in the L-arginine than in the control group (0.04 +/- 0.01 versus 0.19 +/- 0.03 ng x min(-1); p < 0.05). The coronary flow as well as the left ventricular developed pressure were higher in the L-arginine than in the control group before ischemia and remained so throughout the experimentation. CONCLUSIONS: These results indicate that L-arginine administered intraperitoneally 24 hours before cardioplegic arrest reduced myocardial cell injury and seems to protect myocardium against ischemia-reperfusion injury.

Use of cardiac troponin I as a marker of perioperative myocardial ischemia.

Troponin I is a contractile protein comprising three isoforms, two related to the skeletal muscle and one to the cardiac fibers. Cardiac troponin I (CTn I) is specific, without any cross-reactivity with the other two. Several studies have demonstrated its release after acute myocardial infarction. In contrast, CTn I never has been found in a healthy population, marathon runners, people with skeletal disease, or patients undergoing non-cardiac operations. Thus, CTn I is a more specific marker of cardiac damage than common serum enzymes. It is also more sensitive, allowing diagnosis of perioperative microinfarction and detection of acute myocardial infarction much earlier after the onset of ischemia (4 hours). Using a rapid one-step assay, we measured the release of CTn I in two groups of patients after operation: 20 with calcified aortic stenosis and normal coronary arteries (aortic valve replacement group and control group) and 20 undergoing coronary artery bypass grafting. In the overall population CTn I peaked at hour 6 and practically disappeared after day 5. Mean values were higher in the coronary artery bypass grafting group. In the aortic valve replacement group, a positive correlation was found between aortic cross-clamping time and CTn I, which is a reliable marker of cardiac ischemia during heart operations and can be used to evaluate cardioprotective procedures.

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.

Warm reperfusion and myocardial protection.

BACKGROUND: The aim of this study was to determine whether warm reperfusion improves myocardial protection with cardiac troponin I as the criteria for evaluating the adequacy of myocardial protection. METHODS: One hundred five patients undergoing first-time elective coronary bypass surgery were randomized to one of three cardioplegic strategies of either (1) cold crystalloid cardioplegia followed by warm reperfusion, (2) cold blood cardioplegia followed by warm reperfusion, or (3) cold blood cardioplegia with no reperfusion. RESULTS: The total amount of cardiac troponin I released tended to be higher in the cold blood cardioplegia with no reperfusion group (3.9+/-5.7 microg) than in the cold blood cardioplegia followed by warm reperfusion group (2.8+/-2.7 microg) or the cold crystalloid cardioplegia followed by warm reperfusion group (2.8+/-2.2 microg), but not significantly so. Cardiac troponin I concentration did not differ for any sample in any of the three groups. CONCLUSIONS: Our study showed that the addition of warm reperfusion to cold blood cardioplegia offers no advantage in a low-risk patient group.

Prospective study of quality of life before and after open heart operations.

BACKGROUND: The aim of this prospective study, with completion of questionnaires before and 3 months after open heart operations, was to evaluate the improvement of quality of life brought about by these operations and the predictors of this improvement. METHODS: The Nottingham health profile questionnaire contains 38 subjective statements divided into six sections: energy, physical mobility, emotional reaction, pain, sleep, and social isolation. Factors influencing quality of life scores were determined by analysis of covariance. Factors influencing the status of the patients (improved or worsened) were determined by logistic regression. RESULTS: From January to July 1994, 215 consecutive patients underwent elective open heart operations. The comparison between mean preoperative and postoperative scores showed an improvement in all sections of quality of life. An average of 80% of patients were improved by their operations. Independent predictors of less improvement of quality of life scores were as follows: for the energy section, age over 70 and New York Heart Association functional class III or IV; for sleep, age over 70; for physical mobility, New York Heart Association functional class III or IV; for social isolation, female gender; and for pain, age over 70 and abnormal segmental wall motion. Independent predictors of patients worsened by operation were as follows: New York Heart Association functional class III or IV in the energy section (odds ratio = 3.7, 95% confidence interval 1.4 to 9.8) and in the physical mobility section (odds ratio = 2.4, 95% confidence interval 1.02 to 5.5), female gender in the social isolation section (odds ratio = 2.8, 95% confidence interval 1.03 to 7.7), and presence of at least one comorbid disease in the emotional reaction section (odds ratio = 2.5, 95% confidence interval 1.17 to 5.2). CONCLUSIONS: Cardiac operations improve quality of life in patients. The improvement is similar for patients undergoing coronary artery bypass grafting versus valve replacement, and for patients with no postoperative events versus those with nonlethal postoperative complications. The strongest predictive factors for quality of life are age and New York Heart Association functional class.

Aortic valve replacement in the elderly: a comparative assay of potential risk factor modification.

From January 1989 to October 1992, 208 consecutive patients underwent isolated aortic valve replacement for calcified aortic stenosis in our department. Since the mean age of this patient population was 70 +/- 9 years, a retrospective clinical study was completed to assess the potential influence of advanced age on the independent predictors of early and late mortality. Hospital mortality was 6.2% (13 patients). Total follow up was 422.5 patient-years with a mean of 26 months. Nineteen patients died during the follow up period, equivalent to 4.5% per patient-year late mortality rate. Survival including hospital death was 88 +/- 2%, 86 +/- 2% and 79 +/- 4% at one, two and three years respectively. Eighteen variables as potential predictors of early and late mortality were studied. Predictors of hospital mortality were determined by logistic regression analysis, and those of late mortality by Cox proportional hazard model. Results were expressed as odds ratio (OR) or relative risk (RR). Age greater than 70 years (OR = 9.8, 95% CI = 1.2 to 80) and emergency surgery (OR = 8, 95% CI = 2.1 to 31) appeared as independent predictors of hospital mortality in multivariate analysis. Age above 75 years (RR = 3, 95% CI = 1.1 to 8.3), preoperative acute pulmonary edema (RR = 2.9, 95% CI = 1.1 to 7.7) and emergency surgery (RR = 4.2, 95% CI = 1.2 to 15) were independently associated with decreased late survival. Advanced functional class (NYHA III-IV) was shown to be an independent predictor of early or late mortality only in univariate analysis.(ABSTRACT TRUNCATED AT 250 WORDS)

Endarterectomy of the left main coronary artery stenosis by a 'transpulmonary artery approach'.

For better visualization of the left main coronary artery, a new technique involving transection of the main pulmonary artery is described. With this new method it was possible to perform endarterectomy of the left main coronary artery in 35 patients from February 1981 to July 1987. The endarterectomy incision was closed with a pericardial or venous patch. We had no mortality, and 91% are free from angina at a mean follow-up of 31 months. Angiographic evaluation was performed in 19 patients revealing good patency of the left main artery. This procedure is safe, and we recommend it in isolated left main coronary artery stenosis without distal involvement and with good left ventricular function.

Inter-observer reliability in the interpretation of coronary angiograms.

The interpretation of coronary angiograms is indispensable in determining procedure in coronary surgery. The aim of this study was to measure the overall reliability of a group of surgeons in the interpretation of coronary angiograms, surgical procedure and the evaluation of operative risk. Ten coronary angiograms were interpreted by eight cardiac surgeons at four different medical centers. Evaluation of coding discrepancies, in this case of multiple raters applying an ordinal-scale classification scheme (0, 1, 2) with no expert yardstick available for coding, was explored by a two-way random factor analysis of variance. Reliability was substantial for the assessment of stenosis irrespective of the artery (intraclass correlation coefficient (ICC) ranging from 0.92 to 1), and good for the distal part of the artery (ICC ranging from 0.83 to 0.86) as well as for the collateral provision (ICC ranging from 0.75 to 0.94). Agreement between surgeons was good with respect to the number of bypasses to be performed (ICC = 0.88). The number of bypass per patient varied from 2.6 to 3.2 depending on the surgeon. Agreement as to whether or not to bypass was substantial for the right coronary artery (ICC = 0.92), good for the marginal artery (ICC = 0.87) and fair for the left anterior descending artery (ICC = 0.60) and the circumflex artery (ICC = 0.60). There was a higher rate of agreement concerning inferior wall motion (ICC = 0.98) than of the anterior wall motion (ICC = 0.78). Agreement was substantial for ejection fraction (ICC = 0.93), operative risk (ICC = 0.93) and the type of coronary tree (ICC = 0.85). With respect to the overall set of items, no one surgeon disagreed significantly with the rest of the group. Some disagreement regarding anatomy suitable for revascularization exists between surgeons. Surgical assessment of risk is similar. Cardiac surgeons quickly learn to assess risk in a similar manner, even though they might not always graft the same anatomic vessels or assess regional wall motion similarly.

Is surgery for aortic stenosis justified in patients over 75 years of age?

UNLABELLED: The upper age limit for cardiac surgery has constantly been extended since the 1980's, with the most pronounced extension observed in surgery of the calcified aortic stenosis (CAS). The aim of this study was to examine whether surgery is beneficial to the elderly population in terms of hospital mortality, long-term survival and quality of life. Between January 1989 and October 1992, 95 patients over 75 years of age underwent aortic valvular replacement (AVR) for CAS. There were 54 male and 41 female patients with a mean age of 79.7 +/- 2.8 years. All of them suffered from isolated or predominant CAS, associated with a coronary lesion requiring additional bypass procedures in 14 cases. Before surgery 67% of the patients were in NYHA class III and IV and 30% of them had suffered from acute pulmonary edema. Surgical priority was urgent in 10 patients. Mean aortic clamp time was of 55 minutes for the isolated CAS and 78 minutes for the bypass-associated CAS. A Carpentier-Edwards supra-annular bioprosthesis was implanted in 95.7% of the cases, associated with coronary bypass in 14 cases, with a mean of 1.6 bypasses per patient. Global hospital mortality was 11.5%. Emergency surgery was a predictive factor of in hospital mortality in multivariate analysis. Among the 84 survivors, 12 died secondarily, 4 of them due to cardiac causes during the follow-up period (26 +/- 4 months); similar to the mortality rate of the global population for the same age. The factors responsible for this late mortality in multivariate analysis were poor left ventricular status and diabetes mellitus. Survivor's quality of life is excellent with 78.6% of patients termed class I, autonomous and free of sequelae. IN CONCLUSION: despite an operative mortality rate much higher than in patients under 70, AVR for CAS is justified even in patients over 75 years as it offers a good quality of survival and a life expectancy identical to that of the general population of the same age.

Myocardial fixation of anticardiac troponin I antibody and cardiac troponin I release.

BACKGROUND: The threefold aim of this experimental study was to test the correlation of cardiac troponin I released to myocardial infarction size and myocardial fixation of anticardiac troponin I antibody and to determine how long after myocardial infarction the measure of cardiac troponin I concentration can evaluate myocardial infarction size. METHODS: Forty rabbits were assigned either to a control group or to an experimental preconditioned group. Infarction was obtained by tightening a snare around the left anterior descending artery. Serial venous blood samples were drawn for measurement of cardiac troponin I. The rabbits were sacrificed at 72 hours and a histological study was performed to determine the infarct size and the size of the area void of fixation of anticardiac troponin I antibody. RESULTS: There was a linear correlation between the total amount of CTn I released and both infarct size (r=0.45, p<0.02) and the size of the area void of anti-cardiac troponin I antibody (r=0.47, p<0.02). These two sizes were strongly correlated (r=0.95, p<0.02). The hour 9 CTn I sample was the best correlated with both the infarct size (r=0.47, p<0.02) and the size of area void of anticardiac troponin I antibody (r=0.45, p<0.02). CONCLUSIONS: Our study shows that: 1) cardiac troponin I release is correlated to both myocardial infarction size and the size of area void of fixation of anticardiac troponin I antibody, 2) the area void of anticardiac troponin I antibody fixation includes the whole ischemic area, and 3) evaluation of myocardial infarction size can be obtained by CTn I concentration as early as the ninth hour.

Myocardial revascularization using both attached internal thoracic arteries. Mid-term clinical evaluation of 117 cases.

The current trend in myocardial revascularization is to use arterial grafts in most, if not all cases. The right internal thoracic artery was a logical choice once the left internal thoracic artery patency on the LAD was known. This study presents our experience of using both attached internal thoracic arteries (ITA). Between January and October 1990, 159 myocardial revascularizations were performed in our department. In 117 cases, bilateral ITA grafting was used with non exclusion criteria. There were 100 male and 17 female patients, with a mean age of 61 +/- 8. The LITA was anastomosed to the LAD in 44 cases, and to the marginal artery in 74. The RITA was anastomosed to the LAD in 68 cases, to the marginal artery in 47 and to the right coronary artery in 2. An average of 3.5 bypasses per patient, including saphenous vein grafts, were performed. Six patients (5%) died within 30 days. Four patients (3.4%) were diagnosed as having periperative myocardial infarcts. There were no reoperations for bleeding. One patient (0.9%) presented a sternal wound infection. Mean follow-up was 18 +/- 7 months. Six patients died during the follow-up and the survival rate was 91%. Ninety-five patients (91%) were symptom-free, 9 patients had a recurrent angina. Postoperative coronary angiography was performed in 11 patients (10%).(ABSTRACT TRUNCATED AT 250 WORDS)