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PubMed1994

Phospholipid headgroup-headgroup electrostatic interactions in mixed bilayers of cardiolipin with phosphatidylcholines studied by 2H NMR.

The headgroup-headgroup interactions in binary mixed bilayers of diacylphosphatidylcholines (PC) and cardiolipin were analyzed by 2H NMR. Specific changes in the quadrupole splittings of the choline headgroup deuterated PC at alpha,beta-methylenes, and gamma-methyls are observed upon the insertion of the negatively charged tetraacylphospholipid, cardiolipin. The effects are consistent with an electrostatic interaction between PC and cardiolipin headgroups, in which a concerted conformational reorientation of the entire phosphocholine moiety toward the membrane surface is involved. On the basis of the "choline-tilt" model by Macdonald and co-workers (1991) the variations in the quadrupole splittings are consistent with a change in orientation of the choline P-N vector up to 23 degrees for the highest cardiolipin concentrations. Additional information on headgroup conformational changes was obtained through the analysis of the dependence on temperature of the quadrupole splittings for the various deuterium-labeled segments. Evaluation of the deuterium spin-lattice (T1) relaxation times for the deuterons in the various positions of the choline headgroup in mixed bilayers of PC and cardiolipin showed that the internal fast segmental motions were not affected on addition of cardiolipin to PC membranes.

Cardiolipins↗

PubMed1985

ADP/ATP carrier protein from beef heart mitochondria has high amounts of tightly bound cardiolipin, as revealed by 31P nuclear magnetic resonance.

An unusual binding of cardiolipin to the ADP/ATP carrier has been found, which is distinguished by the relatively large amount and by the tightness of binding. High-resolution 31P NMR studies on the detergent-solubilized ADP/ATP carrier from beef heart mitochondria revealed narrow signals from phosphatidylcholine and phosphatidylethanolamine and a broadened signal of 30-40-Hz line width, suggestive of cardiolipin. Line broadening of this magnitude is to be expected when tumbling of the whole protein-detergent micelle is the only source of phosphorus spin-spin relaxation. Thus a strong immobilization of the protein-bound cardiolipin is inferred. By sucrose density gradient centrifugation phosphatidylcholine and phosphatidylethanolamine were removed, while approximately six +/- one molecules of cardiolipin remained tightly bound in the dimeric protein molecule. The cardiolipin binding was stable against treatment with sodium dodecyl sulfate although release of the inhibitor carboxyatractyloside revealed at least partial protein denaturation. Ca2+ ions did not readily interact either with the bound cardiolipin. Complete detachment of the bound phospholipid was achieved by a short heat pulse in the presence of sodium dodecyl sulfate. Denaturation of the carrier protein by guanidinium chloride or NaClO4 also led to release of the bound phospholipid. Thus different stages of protein denaturation must be envisaged.

Animals↗

PubMed1998

Cardiolipin binding a light chain from lupus-prone mice.

Autoantibodies in systemic lupus erythematosus react with multiple epitopes on highly conserved molecules such as nucleic acids, cytoskeletal proteins, phospholipids, and phospholipid-binding proteins. Analysis of the heavy- and light-chain variable sequences (VH and VL) has shown that a restricted set of V genes gives rise to these autoantibodies. Several monoclonal antibodies were developed from a strain of mouse prone to lupus (F1 male NZW x BXSB). Two of these antibodies, A1.72 and A1.84, reacted directly with cardiolipin and their VH and VL sequences were analyzed. Surprisingly, these two antibodies had identical light-chain variable sequences despite having substantially different heavy-chain variable sequences. This VL sequence, VL 72/84 was 97% identical with the germ-line sequences with only four single nucleotide substitutions. When this VL sequence was shuffled with the VH sequence of other monoclonal antibodies and expressed as single chain variable fragment (scFv) in Escherichia coli, it imparted cardiolipin-binding activity to the hybrids. Furthermore, the VL 72/84 sequence, when expressed alone without any VH sequence, also bound to cardiolipin. The antibodies and their recombinant fragments were immunoaffinity-purified on cardiolipin liposomes. The dissociation constant of the light chain for cardiolipin was similar to the intact molecule (21 +/- 0.01 vs 20 +/- 0.03 nM). These studies demonstrate that the VL sequence alone, in the absence of any other immunoglobulin domains, can mediate cardiolipin binding, raising the possibility that antigen specificity of certain antibodies may exclusively reside in their light-chain sequences.

Amino Acid Sequence↗

PubMed2005

Evidence of domain formation in cardiolipin-glycerophospholipid mixed monolayers. A thermodynamic and AFM study.

The interaction of the three main components of the mitochondrial membrane, namely cardiolipin, phosphatidylcholine, and phosphatidylethanolamine, has been studied investigating mixed cardiolipin-phosphatidylcholine and cardiolipin-phosphatidylethanolamine monolayers at different cardiolipin molar fractions. The thermodynamic behavior of the mixed monolayers was investigated by means of surface pressure and surface potential measurements, and atomic force microscopy was employed to characterize the morphology of the monolayers. Langmuir isotherms and surface potential curves show a regular behavior with a progressive transition toward the isotherm of the pure component. Positive deviations from ideality in the excess Gibbs energies of mixing suggest the presence of repulsive interactions in both systems. Analysis of partial molecular dipole moment indicates a discontinuity at a definite cardiolipin/phosphatidylethanolamine molar fraction, suggesting the formation of a stoichiometric complex; as a consequence, in mixed cardiolipin-phosphatidylethanolamine monolayers, a phase separation is observed at phosphatidylethanolamine excess. AFM measurements indicate the presence of two domains: one made by phosphatidylethanolamine and the other by a regular arrangement of phosphatidylethanolamine and cardiolipin at a fixed molecular ratio.

1,2-Dipalmitoylphosphatidylcholine↗

PubMed1990

1H-n.m.r. evaluation of the ferricytochrome c-cardiolipin interaction. Effect of superoxide radicals.

The interaction between ferricytochrome c and cardiolipin was investigated by 1H n.m.r. at 270 MHz. From the phospholipid-induced changes of the protein spectral features it is concluded that the first 2 equivalents of cardiolipin cause a conformational change at the lower part of the solvent-exposed haem edge, involving a rearrangement of the hydrogen-bond interactions of propionate 6, thus partly accounting for the lowered redox potential of cytochrome c in the presence of cardiolipin. The increased value for the pK of the alkaline isomerization of ferricytochrome c shows that cardiolipin stabilizes the native structure of the protein, indicating that the oxidized form assumes ferrocytochrome c-like properties. Peroxidation of cardiolipin by superoxide radical ions drastically decreases the protein binding to this phospholipid. The implications of this finding, and the likelihood of the ternary cytochrome c-cardiolipin-cytochrome c oxidase complex, for the binding of cytochrome c to cytochrome c oxidase in vivo, are discussed in relation to peroxidative damage following ischaemia and reperfusion.

Animals↗

PubMed1997

Asymmetrical distribution of cardiolipin in yeast inner mitochondrial membrane triggered by carbon catabolite repression.

Transmembrane asymmetry of cardiolipin in yeast was monitored during the switch from fermentative to gluconeogenic growth and the reverse. As soon as cells used ethanol as an electron donor to produce ATP by oxidative phosphorylation, rapid and abundant cardiolipin synthesis was observed on the matrix side of the inner mitochondrial membrane followed by a transverse rearrangement between the two leaflets. The cardiolipin distribution changed from about 20:80 (in/out) to 70:30 (in/out), and after translocation towards the outer leaflet it finally became 37:63 (in/out). At the same time, cytochrome c oxidase activity remained stable, then increased as a possible result of the topographical rearrangement. During the reverse process from gluconeogenic to fermentative growth, the amount of cardiolipin rapidly decreased by half, its bilayer distribution apparently changing to a monolayer organization before the 20:80 (in/out) asymmetry of repressed cells was re-established. Experimental impairment of cardiolipin topography by antibiotic inhibition of gene expression or in situ dissipation of mitochondrial membrane potential produced data that prove that the amount and transmembrane distribution of the phospholipid are two specific parameters of the mitochondrial inner membrane organization in both fermentative (2.2 fmol/cell and 20:80, in/out) and gluconeogenic (4.2 fmol/cell and 37:63, in/out) growing yeast cells. Finally, the inner mitochondrial membrane topography of cardiolipin appeared to be closely associated with the transmembrane redox potential.

Biological Transport↗

PubMed1996

Alpha-branched 1,2-diacyl phosphatidylcholines as effectors of activity of cytochrome P450SCC (CYP11A1). Modeling the structure of the fatty acyl chain region of cardiolipin.

Cardiolipin has been shown to be the most effective activator of cholesterol side chain cleavage activity of cytochrome P450SCC, and evidence has been provided for a lipid effector site on the enzyme. Results suggested the headgroup of cardiolipin as major determinant of lipid interaction with P450SCC (Lambeth, J. D. (1981) J. Biol. Chem. 256, 4757-4762). The role of unsaturation is contradictory and open to question (Igarashi, Y. and Kimura, T. (1986) Biochemistry 25, 6461-6466). We synthesized phosphatidylcholines with fully saturated branched fatty acyl chains substituted in the 2-positions of the main chains and studied the influence of these lipids on the activity and other properties of P450SCC in vesicle-reconstituted systems. These saturated branched lipids, with regard to the fatty acyl moiety in molecular shape similar to cardiolipin but with the headgroup of phosphatidylcholines retained, showed a stimulatory efficiency higher than any other phospholipid and at least comparable to cardiolipin. Activation is sensitive to the acyl chain structure and composition. Results suggest that the shape of the molecule at least partially plays an important role in the process of stimulation of the activity of P450SCC. Because binding of cholesterol was increased by the branched lipids monitored optically by the fraction of P450SCC in the high spin form, it was concluded that these lipids, like cardiolipin and other lipids, exert their effects by regulating the binding of cholesterol to P450SCC. These data suggest that polymorphic lipids such as branched phosphatidylcholines and cardiolipin might influence P450SCC function by maintenance of the membrane curvature at a value optimal for activity.

Acylation↗

PubMed2003

Cardiolipin stabilizes respiratory chain supercomplexes.

Cardiolipin stabilized supercomplexes of Saccharomyces cerevisiae respiratory chain complexes III and IV (ubiquinol:cytochrome c oxidoreductase and cytochrome c oxidase, respectively), but was not essential for their formation in the inner mitochondrial membrane because they were found also in a cardiolipin-deficient strain. Reconstitution with cardiolipin largely restored wild-type stability. The putative interface of complexes III and IV comprises transmembrane helices of cytochromes b and c1 and tightly bound cardiolipin. Subunits Rip1p, Qcr6p, Qcr9p, Qcr10p, Cox8p, Cox12p, and Cox13p and cytochrome c were not essential for the assembly of supercomplexes; and in the absence of Qcr6p, the formation of supercomplexes was even promoted. An additional marked effect of cardiolipin concerns cytochrome c oxidase. We show that a cardiolipin-deficient strain harbored almost inactive resting cytochrome c oxidase in the membrane. Transition to the fully active pulsed state occurred on a minute time scale.

ATP Synthetase Complexes↗

PubMed1992

Beta 2-glycoprotein 1 (beta 2GP1) enhances cardiolipin binding activity but is not the antigen for antiphospholipid antibodies.

Some investigators have reported that a serum protein, beta 2-glycoprotein 1 (beta 2GP1), either alone or in combination with negatively charged phospholipid, may be the antigen for anticardiolipin (aCL) antibodies. To examine these reports further, ELISA tests, inhibition experiments, Ouchterlony and Western blot techniques were used to examine anticardiolipin binding to beta 2GP1. Sera from patients with the antiphospholipid syndrome (APS) and syphilis were studied, as well as whole IgG immunoglobulin and affinity purified (a.p.) IgG aCL antibodies. Results showed no binding of aCL antibodies to beta 2GP1 in the absence of cardiolipin. beta 2GP1 caused enhanced binding of aCL antibodies to cardiolipin, but this enhancement was not observed in inhibition experiments. Binding to cardiolipin occurred in the absence of beta 2GP1. Enhancement of cardiolipin binding activity by beta 2GP1 was observed for APS, but not for syphilis. We conclude that beta 2GP1 is not the antigen for aCL antibodies, nor is it likely that the antibody recognizes shared beta 2GP1-cardiolipin epitopes. Instead, this protein may make cardiolipin more available for aCL binding on solid surfaces by some yet undefined mechanism. This effect may not extend to aqueous suspensions.

Antibodies, Anticardiolipin↗

PubMed1995

Direct cardiolipin assay in yeast using the red fluorescence emission of 10-N-nonyl acridine orange.

The dye 10-N-nonyl-3,6-bis(dimethylamino)acridine (10-N-nonyl acridine orange) has been recently identified as a specific probe for cardiolipin (Ka = 2 x 10(6) M-1). It also interacts, at lower affinity (Ka = 7 x 10(4) M-1), with other acidic phospholipids [Petit, J. M., Maftah, A., Ratinaud, M. H. & Julien, R. (1992) Eur. J. Biochem. 209, 267-273]. In order to reduce the interference corresponding to monoacidic phospholipid binding, we have quantified cardiolipin by using a fluorimetric method based on the red fluorescence of the dye dimers formed at the diacidic phospholipid contact. Hence we have demonstrated that: (a) in yeast, the mitochondrion is the target of the dye whatever the cell metabolism; (b) membrane or protein organization and fatty acid unsaturation do not significantly modify the binding of 10-N-nonyl acridine orange. Using thin-walled vesicles, a linear relationship was established between the amount of cardiolipin and the red fluorescence emitted by the dye. Low red fluorescences were also observed with vesicles containing phosphatidylserine and phosphatidylinositol. However, at the same acidic phospholipid concentration, the fluorescence was much higher using cardiolipin-containing vesicles (fivefold that observed with phosphatidylserine-containing vesicles). Thus, 10-N-nonyl acridine orange was applied to cardiolipin quantification in yeast. This new method revealed that cells growing with a high glucose concentration contained 2.2 +/- 0.3 nmol cardiolipin/10(6) cells, whereas with lactate they contained about twice this amount (3.9 +/- 0.3 nmol cardiolipin).

Acridine Orange↗

PubMed1983

The relationship of cardiolipin biosynthesis to mitochondrial protein synthesis in Tetrahymena pyriformis.

The synthesis of cardiolipin has been investigated following the inhibition of mitochondrial protein synthesis with chloramphenicol. Quantitative measurements of the amount of cardiolipin in the cell during treatment with chloramphenicol as well as pulse-labelling studies using labelled acetate were carried out. The results show that while whole cell phospholipid biosynthesis is depressed by the treatment (probably a reflection of a general cessation of growth), there is no sign of any preferential effect on cardiolipin synthesis. The data also show that as cells are reduced in size as they approach stationary phase there is a six- to seven-fold loss of total cellular phospholipids; however, the amount of cardiolipin is only reduced by four- to five-fold. There is a preferential conservation of cardiolipin as stationary phase is approached with the mole percent cardiolipin phosphorus in the cell rising from 5-7% to 10-12%.

Animals↗

PubMedDate not supplied

Oleate stimulation of incorporation of exogenous glycerol into cardiolipin in isolated perfused rat heart does not involve direct activation of the CDP-DG pathway.

Oleate has been shown previously to stimulate the in vitro activity of phosphatidylglycerol-phosphatase, an important enzyme in the cytidine-5'-diphosphate-1,2-diacyl-sn-glycerol pathway of phosphatidylglycerol and cardiolipin biosynthesis. In this study the in vivo effect of oleate on the biosynthesis of new phosphatidylglycerol and cardiolipin was investigated in the heart. Hearts were perfused for 60 min with Krebs-Henseleit buffer containing [1,3-3H]glycerol and 0.6 mM albumin in the absence or presence of 0.6 or 1.2 mM oleate. Total incorporation of radioactivity was higher in the oleate-treated hearts compared with controls and this was due to an exclusive incorporation of radioactive glycerol into the organic phase. Also, the radioactivity incorporated into phosphatidylglycerol and cardiolipin was higher in the oleate-treated hearts compared with controls; however, the increase was greater in hearts perfused with 0.6 mM oleate compared with 1.2 mM oleate, indicating that pathophysiological concentrations of oleate may attenuate the oleate-induced stimulation of glycerol incorporation into polyglycerophospholipids. The pool size of phosphatidylglycerol and cardiolipin were unchanged in oleate-perfused hearts compared with controls. To investigate if the biosynthesis of phosphatidylglycerol and cardiolipin via the cytidine-5'-diphosphate-1,2-diacyl-sn-glycerol pathway was authentically stimulated by oleate hearts were pulse labeled for 15 min with 0.1 mM [1,3-3H]glycerol and subsequently chased for 60 min with 0.1 mM glycerol in the absence or presence of 0.6 mM oleate in the perfusate. Radioactivity incorporated into phosphatidylglycerol and cardiolipin was unchanged compared with controls. Our data indicate that oleate increases the incorporation of exogenous glycerol into polyglycerophospholipids but not accelerate synthesis from prelabeled precursor pools. Accordingly, oleate does not appear to stimulate directly enzymes of the cytidine-5'-diphosphate-1,2-diacyl-sn-glycerol pathway in vivo.

Animals↗

PubMed2003

Decrease in mitochondrial complex I activity in ischemic/reperfused rat heart: involvement of reactive oxygen species and cardiolipin.

Reactive oxygen species (ROS) are considered an important factor in ischemia/reperfusion injury to cardiac myocytes. Mitochondrial respiration is an important source of ROS production and hence a potential contributor to cardiac reperfusion injury. In this study, we have examined the effect of ischemia and ischemia followed by reperfusion of rat hearts on various parameters related to mitochondrial function, such as complex I activity, oxygen consumption, ROS production, and cardiolipin content. The activity of complex I was reduced by 25% and 48% in mitochondria isolated from ischemic and reperfused rat heart, respectively, compared with the controls. These changes in complex I activity were associated with parallel changes in state 3 respiration. The capacity of mitochondria to produce H2O2 increased on reperfusion. The mitochondrial content of cardiolipin, which is required for optimal activity of complex I, decreased by 28% and 50% as function of ischemia and reperfusion, respectively. The lower complex I activity in mitochondria from reperfused rat heart could be completely restored to the level of normal heart by exogenous added cardiolipin. This effect of cardiolipin could not be replaced by other phospholipids nor by peroxidized cardiolipin. It is proposed that the defect in complex I activity in ischemic/reperfused rat heart could be ascribed to a ROS-induced cardiolipin damage. These findings may provide an explanation for some of the factors responsible for myocardial reperfusion injury.

Animals↗

PubMed2006

Anti-cardiolipin antibodies and overall survival in a large cohort: preliminary report.

BACKGROUND: Anti-cardiolipin antibodies have been associated with both arterial and venous thrombosis, but their overall impact on all-cause or vascular mortality is unknown. In this study, we evaluated the influence of anti-cardiolipin antibodies on all-cause and vascular mortality. METHODS: All individuals who fulfilled the inclusion criteria (completeness of data, no admission from an intensive care unit, unique identification with name and date of birth) and whose anti-cardiolipin antibodies were measured between October 2002 and February 2004 were included in this study (n = 4756; 64% female; median age, 46 years). Death/survival and cause of death were obtained from the Austrian Death Registry. The median observation period was 1.5 years, and the study comprised 7189 person-years. RESULTS: During the study period, 184 patients (3.9%) died. There were no associations between either anti-cardiolipin IgM or IgG antibodies and both vascular death and noncancer mortality as outcome variables in a Cox regression analysis adjusted for age and sex. In contrast, the risk of cancer-related mortality was increased 2.6-fold. CONCLUSIONS: Anti-cardiolipin antibodies are associated with cancer mortality, likely as an epiphenomenon of malignancy, but they are not predictive of vascular mortality or noncancer mortality. Hence, although a clear association between anti-cardiolipin antibodies and (mostly nonfatal) vascular events has been described in the literature, our data indicate that this finding is not necessarily associated with an increase in vascular mortality.

Adult↗

PubMed1991

[The predictive value of the anti-cardiolipin antibody test for malignant tumors].

To determine the predictive value of the IgG anti-cardiolipin antibody test for malignant tumor, two groups of the patients of Kurume and Kyushu University Hospitals were examined by quantitative enzyme linked immunoadsorbent assay (ELISA) for their serum anti-cardiolipin antibodies. With the first group of the patients consisting of a mixture of benign diseases and malignant tumors, the antibody was positive at 57% (39/72). With the second, malignant tumor group, 38% (19/50) was positive for the antibody. When examined for the specificity of the antibodies by a binding inhibition assay, it was shown that the antibodies in the tumor patients were less specific to cardiolipin: antibodies to cardiolipin in tumor patients were blocked by the specific antigen, cardiolipin, in a lesser degree than those in the control syphilis patients, and highly cross-reacted with 2 related phospholipids, i.e., phosphatidyl glycerol and phosphatidic acid. These findings obtained in this study suggest that ELISA for cardiolipin has the value for the tumor diagnosis, supplementing already established assays.

Antibodies↗

PubMed1990

Tightly associated cardiolipin in the bovine heart mitochondrial ATP synthase as analyzed by 31P nuclear magnetic resonance spectroscopy.

The bovine heart F0F1-ATPase preparation (Serrano, R., Kanner, B., and Racker, E. (1976) J. Biol. Chem. 251, 2453-2461) has been further delipidated. The lipid-deficient preparation contained 2.5 mol of cardiolipin, 1 mol of phosphatidylcholine (PC), and 1 mol of phosphatidylethanolamine (PE) per mol of F0F1. When reconstituted with asolectin the delipidated preparation exhibited an activity of 13 mumol of ATP hydrolyzed/min/mg of protein which was 88% oligomycin-sensitive. The phospholipids in this preparation were analyzed by 31P NMR spectroscopy to determine if they were immobilized by the enzyme (rendered NMR-invisible). The PC and PE were below the limits of detection under the conditions utilized and the cardiolipin was NMR-invisible until the enzyme was denatured by addition of either 1% sodium dodecyl sulfate or 8 M urea. Addition of cardiolipin to the delipidated preparation and subsequent analysis by NMR spectroscopy revealed that approximately 4 mol of cardiolipin were immobilized per mol of F0F1 ATPase. The enzyme appears to have high affinity for cardiolipin exclusively, since PC (a prominent inner membrane lipid), phosphatidyl serine (an acidic phospholipid), and phosphatidyl glycerol (the precursor to cardiolipin) were not immobilized (rendered NMR-invisible) when added to the delipidated preparation.

Adenosine Triphosphate↗

PubMed2002

Cis/trans isomerisation of unsaturated fatty acids in a cardiolipin synthase knock-out mutant of Pseudomonas putida P8.

The gene encoding cardiolipin synthase ( cls) from the phenol-degrading bacterium Pseudomonas putida P8, which rapidly adapts its membrane lipids to the presence of organic solvents by cis/trans isomerisation of unsaturated fatty acids, was isolated and completely sequenced. The functionality of the predicted gene product was proven by constructing a knock-out mutant that was significantly reduced in its growth rate both at elevated temperatures and in the presence of membrane-active solvents. Though the mutant showed a clear phenotype it was still able to synthesise trace amounts of cardiolipin. As an increase in cardiolipin (diphosphatidylglycerol) content is known to function as a long term membrane adaptation mechanism in pseudomonads, we tested whether the mutant compensates for the lack of the Cls by increased cis/trans isomerisation of unsaturated fatty acids. Increase in cis/trans isomerisation of unsaturated fatty acids was observed for the mutant at zero and low concentrations of 4-chlorophenol; however, cis/trans isomerisation is not able to fully compensate for the lack of cardiolipin production. Possibly, other long-term adaptation mechanisms are instrumental in compensating for the missing cardiolipin synthesis. As the cis/trans isomerase is activated similarly in the mutant and the wildtype, cis/trans isomerisation and cardiolipin production do not display mutual dependency.

Blotting, Southern↗

PubMed1997

Antibodies to cardiolipin may increase the risk of failure of peripheral vein bypasses.

OBJECTIVES: To assess the association between antibodies to cardiolipin and infrainguinal vein graft patency. MATERIALS AND METHODS: Plasma levels of antibodies to cardiolipin, haemostatic factors, lipids and the smoking marker carboxyhaemoglobin were determined preoperatively and 6 weeks postoperatively in 80 patients undergoing infrainguinal vein bypass surgery. Bypass patency was assessed by ankle blood pressure measurements and ultrasound duplex scanning at 1 week, 6 weeks, 3, 6, 9 and 12 months. A localised increase in the graft peak systolic velocity by a factor of 2.5 or more was considered to indicate a significant stenosis. RESULTS: Antibodies to cardiolipin were identified in seven (9%) patients preoperatively. In four of these seven patients the bypasses thrombosed within 3 months after surgery and another two developed stenoses. At 6 months the primary bypass patency, i.e. patency without stenosis, was 14% (95% confidence interval (CI) 0-33%) in patients with antibodies to cardiolipin, as opposed to 57% (95% CI 45-69%) in patients without these antibodies (log rank test: p = 0.03). Diabetes mellitus was also associated with a reduced 6 months primary bypass patency (38% (95% CI 16-60%) vs. 58% (95% CI 45-71%), p = 0.006). A Cox regression analysis showed that both the presence of antibodies to cardiolipin and diabetes independently contributed towards predicting the overall risk of bypass failure. CONCLUSION: Antibodies to cardiolipin were identified in 9% of patients undergoing infrainguinal vein bypass surgery and appeared to be associated with increased risk of bypass failure.

Aged↗