Terlipressin for treating intraoperative hypotension: can it unmask myocardial ischemia?

IMPLICATIONS

After administration of terlipressin to treat hypotension related to induction of general anesthesia, profound hypertension occurred in association with myocardial ischemia and occlusion of the left anterior descending coronary artery. The authors emphasize cautious use of this drug because of such adverse events.

[Procalcitonin in pyelonephritis and acute community-acquired pneumonia in adults]

OBJECTIVES

Procalcitonin (PCT) is an acute-phase protein involved in the specific inflammatory reaction to severe bacterial or fungal infections. This protein does however lack sensitivity in focal infections.

PATIENTS AND METHODS

In this study, we investigated PCT, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), leukocytosis, and fibrinogen levels at admission among adult patients hospitalized for community-acquired pneumonia (n = 33) or pyelonephritis (n = 30) and in a control population (n = 27) of patients with viral infections and non-infectious inflammatory diseases.

RESULTS

Median serum PCT in the control group (0.21 ng/ml) was significantly lower than in the pyelonephritis group (0.46 ng/ml, p < 0.0005) or the pneumonia group (0.88 ng/ml, p < 0.0005). In the control group, median CRP was 51.4 ng/l reaching 220 mg/l in the pyelonephritis and 198 mg/l in the pneumonia group (p < 0.0005 in both cases). The other markers of inflammation investigated (leukocytosis, ESR, fibrinogen) did not show such differences between the control group and the sepsis groups. The sensitivity of PCT (threshold 0.5 ng/ml) was 61% for the diagnosis of pneumonia and 44% for the diagnosis of pyelonephritis. Specificity was 92% in both cases. In comparison, the sensitivity of CRP (threshold 50 mg/l) was 94% and 91% for pyelonephritis and pneumonia respectively with a 33% specificity in both cases.

CONCLUSION

PCT is a specific but poorly sensitive marker of community-acquired pneumonia and pyelonephritis among adults hospitalized in medical wards.

Comparison of two platelet glycoprotein IIb/IIIa inhibitors, tirofiban and abciximab, for the prevention of ischemic events with percutaneous coronary revascularization

BACKGROUND

In the setting of percutaneous coronary revascularization, agents in the class known as platelet glycoprotein IIb/IIIa inhibitors have significantly reduced the incidence of death or nonfatal myocardial infarction at 30 days. We assessed whether there are differences in safety or efficacy between two such inhibitors, tirofiban and abciximab.

METHODS

Using a double-blind, double-dummy design at 149 hospitals in 18 countries, we randomly assigned patients to receive either tirofiban or abciximab before undergoing percutaneous coronary revascularization with the intent to perform stenting. The primary end point was a composite of death, nonfatal myocardial infarction, or urgent target-vessel revascularization at 30 days. The trial was designed and statistically powered to demonstrate the noninferiority of tirofiban as compared with abciximab.

RESULTS

The primary end point occurred more frequently among the 2398 patients in the tirofiban group than among the 2411 patients in the abciximab group (7.6 percent vs. 6.0 percent; hazard ratio, 1.26; one-sided 95 percent confidence interval of 1.51, demonstrating lack of equivalence, and two-sided 95 percent confidence interval of 1.01 to 1.57, demonstrating the superiority of abciximab over tirofiban; P=0.038). The magnitude and the direction of the effect were similar for each component of the composite end point (hazard ratio for death, 1.21; hazard ratio for myocardial infarction, 1.27; and hazard ratio for urgent target-vessel revascularization, 1.26), and the difference in the incidence of myocardial infarction between the tirofiban group and the abciximab group was significant (6.9 percent and 5.4 percent, respectively; P=0.04). The relative benefit of abciximab was consistent regardless of age, sex, the presence or absence of diabetes, or the presence or absence of pretreatment with clopidogrel. There were no significant differences in the rates of major bleeding complications or transfusions, but tirofiban was associated with a lower rate of minor bleeding episodes and thrombocytopenia.

CONCLUSIONS

Although the trial was intended to assess the noninferiority of tirofiban as compared with abciximab, the findings demonstrated that tirofiban offered less protection from major ischemic events than did abciximab.

The human G-protein β3 subunit C825T polymorphism is associated with coronary artery vasoconstriction

AIMS

Abnormal coronary vasomotion plays a role in the clinical expression of coronary artery disease. We hypothesized that the functional C825T polymorphism located in the ubiquitous G-protein beta3 subunit, implicated in the cellular signal transduction of many receptors, could modify artery coronary vasomotion. We assessed the potential association of the pertussis toxin-sensitive G protein beta3 subunit (GNB3) gene C825T polymorphism on coronary vasomotion in humans.

METHODS AND RESULTS

We examined the response of angiographically normal human coronary arteries (n=131) after intravenous injection of methylergonovine maleate, a vasoconstrictor, followed by injection of isosorbide dinitrate, a vasodilator, according to GNB3 genotypes. Coronary vasomotion was assessed with quantitative coronary angiography. Subjects bearing at least one T allele had greater susceptibility to vasoconstriction in response to methylergonovine maleate than CC subjects, whereas vasodilation in response to isosorbide dinitrate did not differ among the different genotypes.

CONCLUSION

The C825T polymorphism of the G-protein beta3 subunit may be a genetic determinant of coronary artery vasomotion in humans.

General synthesis of alpha-substituted 3-bisaryloxy propionic acid derivatives as specific MMP inhibitors

Modulations of alpha and aryl substitutions on 3-aryloxy propionic acid hydroxamates led to novel and potent inhibitors of MMP-2,3,9 and 13, and selectivity versus MMP-1.

From peptide libraries to optimized nonpeptide ligands in the search for S-farnesyltransferase inhibitors

A complete 331,776-member library of tetrapeptides made of 24 amino acid building blocks was synthesized robotically on solid phase and subjected to a deconvolution based on the inhibitory potency of the sublibraries in a HPLC assay of the S-farnesyltransferase activity in vitro. One of the non-natural peptide and noncysteine-containing leads Nip-Trp-Phe-His (Nip=p-nitrophenyl-L-alanine) was optimized chemically to give a proteolytically stable pseudopeptide with a 200-fold potency compared with the original lead. The final compound was converted to the C-terminal ethyl ester: p-F-C6H4-CO(CH2)2-CO-Bta-D-Phepsi[CH2NH]His-OEt (Bta = benzothienyl-L-alanine) and shown to behave as a prodrug which was hydrolyzed back to the C-terminal acid following cell penetration. The method confirmed that several structurally original leads can be discovered in large libraries when deconvolution relies upon a highly specific assay and that these leads can be optimized by chemical modification to impart the final compound the desired pharmacological and pharmacokinetic properties.

[Thrombopenia increased by heparin and danaparoid]

Pathogenesis, frequency, and management of heparin-induced thrombocytopaenia are well-known. They may be related with both unfractioned heparin and low-molecular weight heparin. Suspected heparin must be discontinued as soon as the diagnosis is established. Orgaran (danaparoid sodium) may be used for management of patients with heparin-associated thrombocytopaenia but can itself be associated with a thrombocytopaenia. Our case report allows us to catch in mind such a crossed complication.

Should the angiotensin II antagonists be discontinued before surgery?

Angiotensin II antagonists (AIIA) are part of a new rational treatment of hypertension. Because adverse circulatory effects during anesthesia can occur in patients chronically treated with angiotensin-converting enzyme inhibitors, some clinicians discontinue them at least 24 h before operation. No data are available concerning AIIA administration in patients scheduled for vascular surgery performed under general anesthesia. The aim of this prospective randomized study was to compare hemodynamics during induction of anesthesia in patients chronically treated with AIIA and those of patients not receiving this drug on the morning before operation. Thirty-seven patients chronically treated with AIIA for hypertension were randomly assigned to two groups: Group I: AIIA discontinued on the day before surgery (n = 18); Group II: AIIA given 1 h before anesthesia (n = 19). Patients received sufentanil 0.4 microg/kg, propofol 1.5 mg/kg, and atracurium 0.5 mg/kg. During the procedure, the anesthesiologist was required to maintain systolic blood pressure and heart rate within 30% of baseline values using intravascular fluid administration and vasoconstric- tors (e.g. , ephedrine, phenylephrine, or terlipressin). Hemodynamic variables were recorded each 1 min. Hemodynamic study ended at incision. The number and duration of hemodynamic events were collected, and total doses of vasoactive drugs were noted in each group. Systolic arterial pressure was significantly decreased in Group II at 5, 15 and 23 min after induction of anesthesia (*P < 0.05). In this group, the decrease in systolic arterial pressure was associated with more frequent episodes of hypotension (AIIA withdrawn: 1 +/- 1; AIIA given: 2 +/- 1; P < 0.01), with a larger number of patients developing at least 1 episode of hypotension (AIIA withdrawn: 12; AIIA given: 19; P < 0.01), and a longer duration of an episode of hypotension (AIIA withdrawn: 3 +/- 4 min; AIIA given: 8 +/- 7 min; P < 0.01), and an increased need for vasoactive drugs. In conclusion, blockade of the renin-angiotensin system increases the potential hypotensive effect of anesthetic induction. A severe hypotensive episode, requiring vasoconstrictor treatment, occurs after induction of general anesthesia in patients chronically treated with AIIA. Recommendations to discontinue AIIA drugs on the day before the surgery may be justified.

IMPLICATIONS

This prospective randomized study demonstrated that more severe hypotensive episodes, requiring vasoconstrictor treatment, occur after induction of general anesthesia in patients chronically treated with AIIA and receiving this drug on the morning before operation, in comparison with those in whom AIIA were discontinued on the day before operation. Recommendations to discontinue these drugs on the day before the surgery may be justified.

The formation of chlorophyll from chlorophyllide in leaves containing proplastids is a four-step process

The time course of the different esters of chlorophyllide (Chlide) during the formation of chlorophyll a (Chl) in embryonic bean leaves containing proplastids was investigated by HPLC. After the reduction of photoactive Pchlide (Pchlide) to Chlide, three intermediates, i.e. Chlide geranylgeraniol, Chlide dihydrogeranylgeraniol and Chlide tetrahydrogeranylgeraniol were detected before the formation of Chlide phytol, i.e. authentic Chl. The transformation of Chlide to Chl was found to be much faster in leaves containing proplastids than in etiolated leaves with etioplasts.

Prediction of interindividual variation in drug plasma levels in vivo from individual enzyme kinetic data and physiologically based pharmacokinetic modeling

A strategy is presented to predict interindividual variation in drug plasma levels in vivo by the use of physiologically based pharmacokinetic modeling and human in vitro metabolic parameters, obtained through the combined use of microsomes containing single cytochrome P450 enzymes and a human liver microsome bank. The strategy, applied to the pharmaceutical compound (N-[2-(7-methoxy-1-naphtyl)-ethyl]acetamide), consists of the following steps: (1) estimation of enzyme kinetic parameters K(m) and V(max) for the key cytochrome P450 enzymes using microsomes containing individual P450 enzymes; (2) scaling-up of the V(max) values for each individual cytochrome P450 involved using the ratio between marker substrate activities obtained from the same microsomes containing single P450 enzymes and a human liver microsome bank; (3) incorporation into a physiologically based pharmacokinetic model. For validation, predicted blood plasma levels and pharmacokinetic parameters were compared to those found in human volunteers: both the absolute plasma levels as well as the range in plasma levels were well predicted. Therefore, the presented strategy appears to be promising with respect to the integration of interindividual differences in metabolism and prediction of the possible impact on plasma and tissue concentrations of drugs in humans.

Determining the best animal model for human cytochrome P450 activities: a comparison of mouse, rat, rabbit, dog, micropig, monkey and man

1. In the present study, nine cytochrome P450 enzyme activities in seven species were characterized to allow a practical means of comparing this important metabolic step between various test animals and man. 2. Enzyme activities and kinetic parameters were first determined towards marker substrates for human cytochrome P450 enzymes. Inhibition profiles were then determined with both antibodies directed against various cytochrome P450 enzymes and with chemical inhibitors. 3. Both the enzyme kinetic parameters/enzyme activities, and the inhibition profiles obtained for the animal species were compared with those obtained for human liver microsomes in order to postulate the animal species most similar to man with regard to each individual cytochrome P450 enzyme activity. 4. It was found that, as expected, none of the tested species was similar to man for all the measured P450 enzyme activities, but that in each species only some of the P450 enzyme activities could be considered as similar to man. 5. When it is known which human cytochrome P450 enzymes are involved in the metabolism of a compound, the comparative data presented here can be used for selecting the most suitable species for in vitro and in it no experiments.

Treatment of aortic arch dissection using the elephant trunk technique

The elephant trunk technique was developed to facilitate multiple-stage treatment of extensive aneurysm of the thoracic aorta. However, little information is available concerning its usefulness for aortic dissection. From April 1992 to July 1998, we used the elephant trunk technique for treatment of aortic arch dissection in 22 patients (including 19 men) with a mean age of 58.5 years (range 21 to 85 years). Twelve patients presented with type A dissection (acute in 3 and chronic in 9), 3 with type B acute dissection, and 7 with "non A/non B" dissections with retrograde extension to the aortic arch or entry site located in the aortic arch without involvement of the ascending aorta. All patients had aneurysms of the descending (n = 7) or thoracoabdominal (n = 15) aorta. Procedures were performed under hypothermic circulatory arrest at between 15 degrees and 20 degrees C. Antegrade cerebral perfusion was used in three cases. The procedure was associated with aortic valve replacement and/or coronary bypass in 6 cases and bypass of one or more supraaortic vessels in 13. In two patients the distal end of the elephant trunk was attached with an endovascular prosthesis during the same procedure. The ensuing results in these patients indicate that the elephant trunk technique can be highly effective for treatment of complex aortic arch dissection.

Photoactive protochlorophyllide regeneration in cotyledons and leaves from higher plants

Chlorophyll accumulation during greening implies the continuous transformation of photoactive protochlorophyllide (Pchlide) to chlorophyllide. Since this reaction is a light-dependent step, the study of regeneration of photoactive Pchlide under a continuous illumination is difficult. Therefore this process is best studied on etiolated plants during a period of darkness following the initial photoreduction of photoactive Pchlide. In this study, the regeneration process has been studied using spinach cotyledons, as well as barley and bean leaves, illuminated by a single saturating flash. The regeneration was characterized using 77 K fluorescence emission and excitation spectra and high-performance liquid chromatography. The fluorescence data indicated that the same spectral forms of photoactive Pchlide are regenerated by different pathways: (1) photoactive Pchlide regeneration starts immediately after the photoreduction through the formation of a nonphotoactive Pchlide form, emitting fluorescence at approximately 651 nm. This form is similar to the large aggregate of photoactive Pchlide present before the illumination, but it contains oxidized form of nicotinamide adenine dinucleotide phosphate, instead of the reduced form (NADPH), in the ternary complexes; and (2) after the dislocation of the large aggregates of chlorophyllide-light-dependent NADPH:Pchlide a photooxidoreductase-NADPH ternary complexes, the regeneration occurs at the expense of the several nonphotoactive Pchlide spectral forms present before the illumination.

Rapid assessment of drug metabolism in the drug discovery process

For a few years, in vitro models have been used as part of high-throughput screening (HTS) programs to characterize metabolic stability, drug permeability and drug solubility. This has allowed the rapid selection of lead candidates based not only on pharmacological endpoints but also on biopharmaceutical specifications. What has now become clear is that the huge amount of data produced to sort series of compounds has a limited predictive value when used to predict human pharmacokinetic parameters. More complex in vitro tests together with some simple in vivo tests used as validation steps have been developed in order to provide absolute data that may be used as a complement to lead selection providing reliable predictions not only of human pharmacokinetics but also of potential drug-drug interactions. These models may be used as part of selective drug screening (SDS) programs. Further advances in analytical and in vitro techniques will see some of these models shifting from SDS to HTS programs putting the emphasis on the use of expert systems and physiologically based pharmacokinetic models (PBPK) to provide meaningful endpoint data.

Conformational transition of acidic peptides exposed to minerals in suspension

Mineral surfaces probably participated in the chemical processes which led to life in the primitive oceans. The ordered conformations of simple acidic peptides exposed to insoluble minerals are described. Alternating poly(Glu-Leu) adopts a random coil conformation in water due to charge repulsion. The polypeptide extracts cations from insoluble crystalline CdS or molybdenum and adopts an ordered conformation. CdS leads to the formation of beta-sheets whereas molybdenum leads to alpha-helices. Peptides with at least 10-amino acids are necessary to exhibit a significative adsorption onto the surface. Under the same conditions, montmorillonite adsorbs the polypeptide but does not induce any conformational change.

Absence of relationship between plasma Lp(a), Lp-AI, anti-oxidized LDL autoantibodies, LDL immune complexes concentrations and restenosis after percutaneous transluminal coronary angioplasty

To determine the relation between the concentration of Lp(a), LpAI, immunological markers of LDL oxidation (antioxidized-LDL autoantibodies (LDL-AB), LDL immune complexes (LDL-IC)) and restenosis after percutaneous transluminal coronary angioplasty (PTCA) in a Caucasian population (France), we studied 77 consecutive patients who successfully underwent PTCA. All were evaluated by follow-up angiography at an average of 6 months after PTCA and were divided into two groups: existence of restenosis (32 patients, group (G+)) and absence of restenosis (45 patients, negative group (G-)). The prevalence of diabetes mellitus was higher in the restenosis positive group than in the negative group (28% versus 2% respectively, P=0.001). Before and after adjustment in diabetes mellitus frequency there was no difference in the usual lipid parameters (total cholesterol, LDL-cholesterol, HDL-cholesterol, triglycerides, phospholipids, apolipoprotein AI, apolipoprotein B) between the two groups of patients nor in the other parameters (Before adjustment: Lp(a): 0.306+/-0.352 g/l (G+) vs. 0.263+/-0.270 g/l (G-); LpAI: 0.414+/-0.126 g/l (G+) vs. 0.390+/-0.092 g/l (G-); LDL-AB: arbitrary unit (AU) 3.75+/-1.91 (G+) vs. 3.67+/-1.24 (G-); LDL-IC: (AU) 0.93+/-0.82 (G+) vs. 0.86+/-0.44 (G-)). Spearman correlation coefficients did not report any correlation between late loss, loss index, gain and the above mentioned plasma parameters. In conclusion, usual tested plasma lipids, Lp(a), LpAI and in vivo markers of LDL oxidation (LDL-AB and LDL-IC) are not risk factors for restenosis after PTCA in this French population.

[Endovascular treatment of aorto-iliac aneurysms. Made-to-measure endoprotheses increase the feasibility]

The authors describe their experience of tailoring endoprostheses for endovascular treatment of aorto-iliac aneurysms with components available on the market. Between January 1996 and December 1999, 188 aorto-iliac aneurysms were treated by tailor-made endoprostheses using self-expanding Z stents made of stainless steel compiled with polyester ligatures and covered with standard commercially available polyester prostheses. These endoprostheses were implanted with an 18 to 24 Fr (usually 20 Fr) introducer and positioned by a surgical approach. This method allows construction of tubular, bifurcated, digressive or occlusive endoprostheses associated with an extra-anatomical bypass graft. It increased the number of endovascular procedures for aorto-iliac aneurysms in the authors' department. This number has been further increased by using endoprostheses with an uncovered proximal or distal stent for cases with particularly short or angled necks and by using hybrid endoprostheses with one or more extremities without a stent, allowing surgical suture of the anastomosis. The authors' results show that tailoring endoprostheses considerably increased the feasibility of endovascular treatment of aorto-iliac aneurysms, even in unselected patients whilst providing an effectiveness and safety to justify the continuation of this experience.

Determination of absolute configurations of amines and amino acids using nonchiral derivatizing agents (NCDA) and deuterium NMR

Enantiomeric analysis and empirical determination of the absolute configuration of amines and amino acids can be easily performed using acetyl-d(3) chloride as a nonchiral derivatizing agent (deuterium probe) and deuterium NMR in a chiral solvent (Courtieu's method). In the case of amino acids, derivatization to amido esters, performed with methanol-d(4) and acetyl-d(3) chloride, gives a double opportunity for enantiomeric analysis.

Spectroscopic properties of protochlorophyllide analyzed in situ in the course of etiolation and in illuminated leaves

The spectroscopic properties of photoactive (i.e. flash-transformable) and nonphotoactive protochlorophyll(ide)s (Pchl(ide)) were reinvestigated during the development of bean leaves in darkness. Two phases in the process of Pchl(ide) accumulation were apparent from quantitative measurements of pigment content: a lag phase (first week) during which photoactive Pchl(ide) accumulated faster than nonphotoactive Pchl(ide); and a fast phase (second week), showing parallel accumulation of both types of Pchl(ide). 'Flashed-minus-dark' absorbance difference spectra recorded in situ at 77 K showed that P650-655 was the predominant form of photoactive protochlorophyllide regardless of developmental stage. Quantitative analysis of energy migration processes between the Pchl(ide) forms showed the existence of energy transfer units containing a 1:8 ratio of nonphotoactive and photoactive Pchl(ide)s during development. Gaussian deconvolution of in situ 77 K fluorescence spectra indicated that the 633 nm band of nonphotoactive Pchl(ide) was made of four bands, at 625, 631, 637 and 643 nm, whose relative amplitudes only slightly changed during development. The emission band of photoactive Pchlide was also analyzed using the same method. Three components were found at 644, 652 and 657 nm. The emission band of P650-655 included the last two components, which become predominant only in fully etiolated plants. Photoactive Pchlide with an emission maximum at 653 nm was detected in the light during development of leaves of photoperiodically grown plants.

[Multicenter study of intrafamilial transmission of hepatitis C virus in human immunodeficiency virus infection]

OBJECTIVE

Intrafamilial transmission of hepatitis C virus in human immunodeficiency virus and hepatitis C virus co-infections is not well documented. This cross-sectional study evaluated the transmission of hepatitis C virus in the sexual partners of hepatitis C virus and human immunodeficiency virus co-infected patients.

METHODS

Hemophiliacs and transfused hepatitis C virus and human immunodeficiency virus co-infected patients who were being seen in three French university hospitals, and their sexual partners were studied by a face-to-face interview using an epidemiological questionnaire and by biological tests: antibodies against hepatitis C virus, hepatitis C virus RNA, and ALT activity.

RESULT

Fifty-two subjects were included: 26 cases and their 26 sexual partners. Three sexual partners (11.5 %) had anti-hepatitis C virus antibodies, two of whom had an undetermined RIBA test. All three had a risk factor for hepatitis C virus infection (transfusion, intra-muscular injections with re-usable needles). Two of these three partners were also human immunodeficiency virus antibody positive. Hepatitis C virus RNA was negative in all sexual partners.

CONCLUSION

This study provides evidence of a low prevalence of anti-hepatitis C virus antibodies in sexual partners of hepatitis C virus and human immunodeficiency virus co-infected patients. It does not support intra-familial transmission of hepatitis C virus.

Clinical and angiographic results with the ACS MULTI-LINK DUET trade mark Coronary Stent System - the DUET Study

BACKGROUND: The DUET Study is a multicenter prospective efficacy and safety evaluation of the ACS MULTI-LINK DUET coronary stainless steel balloon-expandable stent. AIMS: The primary objective was to determine the one-month incidence of MACE (major adverse cardiac events). The secondary objectives were the acute success rate, the restenosis and reocclusion rates (assessed by quantitative coronary angiography (QCA)) at six months and the occurrence of MACE in hospital and at six months. METHODS: Two hundred and ten patients were enrolled between February and June 1998 in 18 European centers. Successful stent placement was achieved in 209 patients. All patients were treated with ticlopidine 500 mg/day for one month and with aspirin >/=100 mg/day. To allow the investigators to gain familiarity with the stent system, the first one to three patients per center formed a separate lead-in population leaving an intention-to-treat population of 157 patients. The majority of the intention-to-treat population were male (79%); 28% had unstable angina, 69% had stable angina, 44% had had a previous myocardial infarction, 15% had had a previous percutaneous transluminal coronary angioplasty, and 3% had a history of stroke. The target vessel was 38.5% left anterior descending artery, 20.5% left circumflex artery and 41.0% right coronary artery. RESULTS: All but one of the intention-to-treat patients were effectively stented (17 required multiple stents). Six-month angiographic follow-up was available in 90% of the intention-to-treat population. Minimal lumen diameter (MLD) postprocedure was 2.61 +/- 0.33 mm, with a residual diameter stenosis of 16%. Six-month follow-up data showed an MLD of 1.87 +/- 0.56 mm with a residual diameter stenosis of 36%. The binary restenosis rate (>/=50% residual stenosis) was 15.6%. Up to one month following the procedure 94.9% of the population was MACE-free, with two subacute occlusions. At six months all patients were alive, of whom 82.8% were MACE-free, and 73% were free of anginal complaints. CONCLUSION: The results observed in the current DUET registry are comparable to data of other balloon-expandable-stent trials, with a low incidence of clinical events at follow-up.

[Risk factors for mortality in abdominal aortic surgery]

OBJECTIVE

To analyse pre and peroperative variables for predicting mortality after abdominal aortic surgery.

STUDY DESIGN

Prospective study.

PATIENTS

We prospectively included 658 consecutive patients undergoing abdominal aortic surgery from January 1993 to July 1997.

METHODS

Age, gender, hypertension, history of myocardial infarction or coronary revascularization, angina pectoris, diabetes, arrhythmia, cardiac insufficiency, serum creatinine > 150 mumol.L-1, beta-blockers therapy, calcium channel inhibitors, angiotensin converting enzyme inhibitors were preoperative analysed variable. Type of aortic disease (anuerysms versus aortic occlusion), duration of surgery, blood loss, type of laparotomy (medium versus lombotomy) were peroperative analysed variables. Haemoglobinemia was monitored during surgery and patients were transfused if haemoglobinaemia < 80 g.L-1.

RESULTS

Thirty-three patients died after aortic surgery (5%). In multivariate analysis, angina pectoris (OR = 5.47, P < 0.001), chronic obstructive bronchopulmonary disease (OR = 2.27, P = 0.05) and duration of surgery (OR = 1.60, P < 0.001) were the independent predictive factors of mortality. Age, blood loss were predictive factors only in univariate analysis.

CONCLUSION

Angina pectoris and COBP were the two independent preoperative factors of mortality. The duration of surgery was the only peroperative factor. Well monitored blood loss was not a predictive factor.

Cardiac troponin I is reliable with immediate but not medium-term cardiac complications after abdominal aortic repair

BACKGROUND

The diagnosis of cardiac complications is particularly challenging in the postoperative course of non-cardiac surgery. Follow-up of patients suggests that silent or symptomatic postoperative myocardial infarction have similar short-term outcomes. Cardiac troponin I (cTnI) has been reported as being a sensitive and specific marker of these complications.

METHODS

We conducted a prospective study to determine the cut-off values of cTnI which may predict cardiac complications, i: in the postoperative period until discharge, and ii: during a 1-year period after aortic surgery. Three hundred and twenty-nine consecutive patients undergoing infrarenal aortic surgery were included over a 2-year period in a single center. cTnI was measured at recovery and on the 1st, 2nd and 3rd postoperative days. The presence or absence of cardiac complications was classified by reviewers who had no knowledge of cTnI. For evaluation of the ideal discrimination value of cTnI between the complicated and uncomplicated patient groups, we calculated receiver-operator characteristics for the mean values of the peak of cTnI.

RESULTS

Thirteen patients (4%) developed 19 postoperative cardiac complications. Thirteen patients (4%) died in the postoperative period. Nine patients (3%) developed 10 cardiac complications during the 1-year follow-up in 316 patients. In 280 patients, cTnI was below 0.5 ng/ml, in 22 patients between 0.5 and 1.5 ng/ml and the 27 remaining patients had a cTnI higher than 1.5 ng/ml. The area under the curve for postoperative cardiac complications was 0.84 (SD=0.21). A limit value of 0.54 ng/ml yielded a sensitivity of 75% and a specificity of 89%. The area under the curve for late cardiac complications was 0.45 (SD= 0.13).

CONCLUSION

A cTnI level greater than 0.54 ng/ml appears to be correlated with the occurrence of cardiac complications in the period until discharge, but no value of cTnI is predictive of late cardiac complications occurring in the 1st year after aortic surgery.