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The aim of the case-control study was to explore the effect of coagulation factor XIII (FXIII) B subunit (FXIII-B) polymorphisms on the risk of coronary artery disease, and on FXIII levels. In the study, 687 patients admitted for coronary angiography to investigate suspected coronary artery disease and 994 individuals representing the Hungarian population were enrolled. The patients were classified according to the presence of significant coronary atherosclerosis (CAS) and history of myocardial infarction (MI). The F13B gene was genotyped for p.His95Arg and for intron K nt29756 C&gt, G polymorphisms, the latter results in the replacement of 10 C-terminal amino acids by 25 novel amino acids. The p.His95Arg polymorphism did not influence the risk of CAS or MI. The FXIII-B intron K nt29756 G allele provided significant protection against CAS and MI in patients with a fibrinogen level in the upper tertile. However, this effect prevailed only in the presence of the FXIII-A Leu34 allele, and a synergism between the two polymorphisms was revealed. Carriers of the intron K nt29756 G allele had significantly lower FXIII levels, and FXIII levels in the lower tertile provided significant protection against MI. It is suggested that the protective effect of the combined polymorphisms is related to decreased FXIII levels.

The average wall shear stress (WSS) is in 1 Pa range in coronary arteries, while the stretching effect of an implanted coronary stent can generate up to 3 × 105 times higher circumferential stress in the vessel wall. It is widely accepted that WSS plays a critical role in the development of restenosis after coronary stent implantation, but relevant clinical endpoint studies are lack-ing. Fluid dynamics modeling suggests an association between WSS and intimal hyperplasia, however, such an association is not established when the compensating healing process becomes an overshoot phenomenon. This review summarizes available clinical results and concepts of potential clinical importance.

Introduction Our aim was to investigate the association of elevated homocysteine (Hcy) and lipoprotein(a) Lp(a) with the prevalence of coronary artery disease (CAD) and myocardial infarction (MI) and to investigate their interaction in both genders. Materials and methods 955 (male/female: 578/377) consecutive patients admitted for coronary angiography were enrolled in the study. Lp(a), Hcy, vitamin B12, folic acid, MTHFR C677T polymorphism and traditional risk factors were determined. Results 619 patients had significant (≥ 50%) stenosis (CAD+) and 341 had MI (MI+). CAD-MI- cases (n = 302) were considered as controls. Adjusted Hcy levels were significantly elevated only in the female CAD + MI + group that was related to decreased vitamin B12 levels. Lp(a) was elevated in the CAD + MI + group of both genders. Folic acid levels and MTHFR T677 allele frequency did not show significant difference. Moderate hyperhomocysteinemia (Hcy > 15 μmol/L) or elevated Lp(a) (> 300 mg/L) increased the risk of CAD (OR 2.27, CI 1.36-3.80 and OR 1.64, CI 1.03-2.61, respectively) and MI (OR 2.52, CI 1.36-4.67 and OR 1.89, CI 1.06-3.38, respectively) only in women. Only simultaneous but not isolated elevation of Hcy and Lp(a) conferred a significant, 3.6-fold risk of CAD in females and even higher (11-fold) risk in young females, which suggested an interactive effect. Conclusions Moderate hyperhomocysteinemia or elevated Lp(a) level associated with a risk of CAD and MI only in women. While isolated elevation of one of the two parameters represented a mild risk of CAD, their combined elevation highly increased the risk in females. No such effect was observed in males.

Introduction The effect of factor XIII A subunit (FXIII-A) Val34Leu polymorphism on the risk of coronary artery disease (CAD) has been extensively studied. In this study we investigated how FXIII-A Val34Leu genotypes influence plasma factor XIII levels in patients with coronary sclerosis (CS) and myocardial infarction (MI) and how fibrinogen level modulates this effect. Patients and methods 955 consecutive patients admitted for coronary angiography were categorized according to the presence or absence of significant CS and the history of MI. The frequency of FXIII-A Val34Leu polymorphism, fibrinogen, FXIII activity and antigen levels were determined. Results and conclusions CS or MI decreased FXIII levels in patients homozygous for FXIII-A Leu34 allele, but not in heterozygous or wild type patients. In the subgroup of patients with CS, but without the history of MI no significant effect was detected, which suggests that MI has a more prominent role. The specific activity of plasma FXIII was independent of FXIII-A Val34Leu genotype. FXIII and fibrinogen levels significantly correlated in CS+ and MI+ patients. In MI+ patients of Leu/Val or Leu/Leu genotypes and with fibrinogen levels in the lowest quartile, FXIII levels were lower than in the same patient groups, but with higher fibrinogen level. The low-scale continuous activation of blood coagulation in CAD patients could lead to parallel FXIII and fibrinogen consumption. As the same amount of thrombin activates more Leu34 FXIII than Val34 FXIII, increased FXIII consumption might be responsible for the decreased FXIII levels in Leu34 homozygous CAD patients.

Introduction The results on the association of factor XIII (FXIII) A subunit (FXIII-A) Val34Leu polymorphism with the risk of myocardial infarction (MI) are rather inconclusive. The original paper and confirmatory reports demonstrated a protective effect of the mutation, but results demonstrating the lack of protection have also been published. Gene–gene and gene–environmental interactions have been proposed to be responsible for the opposing results. As the rate of change in fibrin clot permeability with increasing fibrinogen concentrations decreased stepwise with increasing number of Leu34 alleles it was proposed that the protection by Val34Leu polymorphism become effective only at higher fibrinogen concentrations. However, this hypothesis has not been tested on patients with coronary artery disease. Patients and methods 955 consecutive patients admitted for coronary angiography were categorized according to the presence or absence of significant coronary sclerosis (CS) and according to positive or negative history of MI. The frequency of FXIII-A Val34Leu polymorphism, and a number of risk factors, including fibrinogen were determined in the patients. FXIII-A Val34Leu polymorphism was also investigated in a population control group of 1146 subjects. Results The presence of FXIII-A Leu34 allele or homozygous Leu34 genotype did not change the risk of CS or MI in the general Hungarian population. However, when patients with fibrinogen level in the upper quartile were separately investigated, the Leu34 allele provided a statistically significant protection against MI. Conclusions Fibrinogen concentration modulates the effect of Leu34 allele on the risk of MI; its protective effect emerges at increasing fibrinogen concentration.

Polar map display (PM) is a comprehensive interpretation of the left ventricle. This is a non-rigid registration of the left ventricle originally for the visual and quantitative analysis of tomographic myocardial perfusion scintigrams. In this scheme the maximal-count circumferential profiles of well-defined short- and long-axis planes are plotted to a map showing the distribution of the perfusion tracer onto a two-dimensional polar representation. The usual coronary artery distribution is often indicated on the PMs of SPECT studies by referring to the regions of the three main coronary branches, nevertheless, the individual variations may differ extensively. We set out to develop an Access (Microsoft)-based computer program that permits an integrated evaluation of the imaging results (coronary angiography, echocardiography and SPECT) on patients with coronary artery disease. This semi-quantitative registration of the coronary tree to a PM focused on the relation between the supplying coronary branches and the myocardial regions of the 16-segment left ventricular evaluating model. All the recorded anatomical and functional data were related to these 16 left ventricular segments, which allowed the direct comparison and holistic synthesis of the results. Two projections were taken into consideration for generation of the coronary PM: from the right anterior oblique projections, the left anterior descendent (LAD)/right coronary artery (RCA) border was assessed through the comparison of the left and right coronary angiograms. The terminations of the visually detected end-arteries showed the separation of the myocardial beds supplied by the two branches. The border of the myocardial beds on the polar map was determined on the "vertical axis" of the local coordinate system. The RCA/ left circumflex (LCx) separation can be determined from the left anterior oblique view. In this projection, the left ventricular septal edge was delineated by the LAD, while the LCx indicated the lateral epicardial surface. The individual coronary artery circulation was typified from among 12 variations in the Holistic Coronary Care program. With this determination of the individual coronary circulation, the lesion-associated segments are generated automatically by the software. The lesion-associated regions are defined as the myocardial bed of a diseased artery distal to the lesion. The PMs generated from the coronary angiographic results were compared with those of 99Tc-labelled MIBI single photon emission computed tomography (SPECT) in order to test the accuracy of the localizing method. The overlap between the segments associated with the coronary lesion and the stress perfusion defects (

The coronary angiography giving the morphological data of epicardiac coronary stenoses and non-invasive tests sometimes even together are insufficient for evaluating the functional consequences of the epicardiac coronary stenoses. However, catheterisation allows us to detect the blunting of coronary flow increase during maximal vasodilatation (coronary flow reserve, CFR, e.g. by Doppler flow wire) and by measuring the translesional pressure gradient by pressure wire (fractional flow reserve, FFR) providing accurate functional assessment. According to this concept the authors have developed a complex cardiac database management program (Holistic Coronary Care, HCC). The database has been built on client-server technology where the central object is the 16-segment polar map. The system contains contextual and graphical elements for a quick data entry. By the assessment of 16 left ventricular segments on a polar map display there is a possibility for direct comparison of the invasive functional and morphologic and the non-invasive functional data. Details measured by pressure or Doppler wire are also stored in the coronary evaluating unit and the coronary segments are rendered to the supplied left ventricular segments. For the correct indication of coronary interventions (from functional and financial point of view) it is important to verify unambiguously the functionally significant coronary stenoses. To the best of our knowledge, the necessity of percutan or surgical intervention can be decided the most accurately by FFR and CFR, furthermore CFR objectively shows the failure of the coronary microvasculature.