Emilia Balogh

Interaction between homocysteine and lipoprotein(a) increases the prevalence of coronary artery disease/myocardial infarction in women: a case-control study.

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 >15μmol/L) or elevated Lp(a) (>300mg/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.

Factor XIII B Subunit Polymorphisms and the Risk of Coronary Artery Disease

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>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.

Wall shear stress in the development of in-stent restenosis revisited. A critical review of clinical data on shear stress after intracoronary stent implantation.

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.

Database management expert program for integrated evaluation of non-invasive and invasive results of coronary heart disease

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.

Plasma homocysteine levels are related to medium-term venous graft degeneration in coronary artery bypass graft patients

Objective: Saphenous venous grafts (SVGs) are established choices for coronary artery bypass grafting (CABG); however, their lumen patency is limited. Our goal was to investigate the risk factors of SVG degeneration. Methods: Seventy-five patients (mean age, 57.5±10.4 years) with 133 SVG conduits who had cardiac catheterization ≥1 year after CABG were selected; follow-up period was 67.6±36.8 months. Patients were divided into 3 groups according to angiographic status at follow up [intact: <20% (n=23); narrowed: 20–99% (n=24); and occluded (n=28)]. Baseline clinical conditions were evaluated in relation to follow-up angiography. As onset date of chronic total occlusions is usually uncertain, they arise typically from thrombotic lesions; thus, their value in evaluation is limited. Results: There were no significant differences between the 3 groups in clinical parameters. Linear correlation analysis found significant (p<0.01) positive connection of SVG disease (luminal diameter reduction 20–99%) with C-reactive protein (CRP) and homocysteine (Hcy), as well as between CRP and Hcy. Multiple regression analysis showed plasma Hcy level to be significantly related to graft diameter reduction normalized to time elapsed until angiography in narrowed grafts: 1 µmol/L increase of Hcy was associated with 0.053%/month decrease in lumen diameter (p<0.01; R2=0.428); extrapolating: +10 µmol/L higher Hcy level during 5 years is associated with 32.1% lumen reduction. Conclusion: Medium- to long-term SVG degeneration is related to elevated plasma total Hcy in patients with sub-occlusive graft stenosis, while in cases with intact SVGs, the beneficial local flow conditions may protect the grafts from degeneration.