Mohamed Sami Mourali

The paraoxonase L55M and Q192R gene polymorphisms and myocardial infarction in a Tunisian population.

OBJECTIVES In the present study, we examined a possible association between the PON1 Q192R and L55M polymorphisms and myocardial infarction (MI) in a sample of the Tunisian population. DESIGN AND METHODS Three hundred and ten patients with MI and 375 controls were recruited. Paraoxonase gene polymorphisms at codon 192 and 55 were analyzed by PCR-RFLP. RESULTS Genotype distributions and allele frequencies of L55M were similar among the control and MI groups. For the Q192R polymorphism patients with MI had significantly higher frequency of the RR genotype compared to controls [17.1% vs. 10.9%; OR (95% CI), 1.93 (1.24-3.02); p=0.004]. The MI patient group showed a significantly higher frequency of the R allele compared to the controls [38% vs. 30%; χ(2)=10.74, p=0.001]. The association between the PON1 Q192R polymorphism and MI remained significant after adjustment for other well-established cardiovascular risk factors. CONCLUSIONS The present study showed a significant and independent association between the PON1 Q192R polymorphism (presence of R allele) and MI in the Tunisian population.

Polymorphisms of the NOS3 gene and risk of myocardial infarction in the Tunisian population.

Controversial results regarding the association of eNOS gene (NOS3) polymorphisms with myocardial infarction (MI) have been reported. This study investigated the relationship of the -786T>C (rs2070744), 894G>T (rs1799983) and 4a4b polymorphisms of the NOS3 gene with the presence of MI in the Tunisian population. In addition, we also examined the association of NOS3 gene haplotypes with MI in Tunisian subjects. A total of 303 patients with MI and 225 controls were included in the study. The 894G>T and -786T>C single nucleotide polymorphisms were analyzed by PCR-RFLP, and 4a4b polymorphism just for PCR. There was significant linkage disequilibrium between the three NOS3 polymorphisms (p<0.0001). The genotype distribution and allele frequency of NOS3 4a4b, but not -786T>C and 894G>T, polymorphism was significantly different between MI patients and controls. The univariate logistic regression analysis showed a significant association of the 4a4b polymorphism and MI according to co-dominant, dominant and recessive models (co-dominant model OR: 4.38, 95%CI: 1.24-15.41; p=0.021, dominant model OR: 1.66, 95%CI: 1.14-2.42); p=0.007, and recessive model OR: 3.85, 95%CI: 1.10-13.47; p=0.035). The multivariate analysis, adjusted for traditional cardiovascular risk factors, revealed that the NOS3 4a4a genotype was an independent predisposing factor to MI, according to the models considered. In addition, a haplotype 7 (C-T-4a), (OR=12.05, p=0.010) was a risk factor of MI after controlling for classical risk factors. These finding suggest that the 4a4b polymorphism of the NOS3 gene was associated with MI in Tunisian patients.

Association of rs2781666 G/T polymorphism of arginase I gene with myocardial infarction in Tunisian male population

OBJECTIVES The aim of this study was to investigate the association between rs2781666 G/T polymorphism of arginase I (ARG I) gene and myocardial infarction (MI) in the Tunisian male population. DESIGN AND METHODS Three hundred eighteen patients with MI and 282 controls were recruited. The rs2781666 G/T polymorphism of ARG I was determined by PCR-RFLP analysis. RESULTS Patients had significantly higher frequency of TT genotype compared to controls (10.4% vs. 6.7%; p<0.001). The MI patients showed higher frequency of T allele compared to the controls [0.33 vs. 0.22; OR (95% CI), 1.79 (1.37-2.34), p<0.001]. The association between rs2781666 G/T polymorphism of ARG I gene and MI remained significant after adjustment for other well-established risk factors. CONCLUSION A significant association between rs2781666 G/T polymorphism of ARG I gene and MI was found in the Tunisian male population.

Acute myocardial infarction in a patient with hypofibrinogenemia: a case report

IntroductionCongenital fibrinogen deficiency is a rare coagulation disorder usually responsible for hemorrhagic diathesis. However, it can be associated with thrombosis and there have been limited reports of arterial thrombotic complications in these patients.Case presentationA 42-year-old Tunisian man with congenital hypofibrinogenemia and no cardiovascular risk factors presented with new onset prolonged angina pectoris. An electrocardiogram showed features of inferior acute myocardial infarction. His troponin levels had reached 17 ng/L. Laboratory findings confirmed hypofibrinogenemia and ruled out thrombophilia. Echocardiography was not useful in providing diagnostic elements but did show preserved left ventricular function. Coronary angiography was not performed and our patient did not receive any anticoagulant treatment due to the major risk of bleeding. Magnetic resonance imaging confirmed myocardial necrosis. Our patient was managed with aspirin, a beta-blocker, an angiotensin-converting enzyme inhibitor and statin medication. The treatment was well tolerated and no ischemic recurrence was detected.ConclusionAlthough coronary thrombosis is a rare event in patients with fibrinogen deficiency, this condition is of major interest in view of the difficulties observed in managing these patients.

Association between endothelial nitric oxide gene intron 4a4b VNTR polymorphism and plasma homocysteine concentrations in Tunisian male patients with myocardial infarction.

Many studies have shown that hyperhomocysteinemia may be an independent risk factor for coronary artery disease. However, not all prospective studies support an association between elevated plasma homocysteine levels and coronary artery disease. Nitric oxide (NO) plays a relevant role in various events during atherogenesis, and in vitro data suggest that NO may modulate total homocysteine (tHcy) concentrations, whereas polymorphisms of the endothelial nitric oxide (NOS3) gene have been reported to be related to an increased risk of myocardial infarction (MI) and hyperhomocysteinemia, but the results have been controversial. We hypothesized that the NOS3 synthase 4a4b VNTR polymorphism is a determinant of tHcy concentrations and tested this in 310 patients with MI and 250 controls. The NOS3 gene intron 4a4b VNTR polymorphism was analyzed by polymerase chain reaction analysis. There was no significant difference in the homocysteine levels between patients with MI and controls. The frequencies of the NOS34b4b, 4b4a, and 4a4a genotypes in the MI group were significantly different from those in the control group. In patients with MI, plasma tHcy concentrations were significantly different among the NOS3 genotypes (13.5±4.5, 18.5±3.9, and 20.4±2.1 μmol/L for 4b4b, 4a4b, and 4a4a genotypes, respectively; P<.001). However, no significant difference was observed for tHcy concentrations in the control group. In conclusion, the NOS34a4b gene polymorphism (presence of 4a allele) is associated with MI and influences plasma tHcy concentrations in patients with MI in the Tunisian male population.

C(− 260)T polymorphism in the promoter of CD 14 gene is not associated with myocardial infarction in the Tunisian population

Recent findings suggest that inflammation plays a role in atherosclerosis and its acute complications. Several known mechanisms may play at least a partial role in this process. One of the most likely mechanisms involves lipopolysaccharide (LPS) and its receptor, CD14. The C(-260)T single nucleotide polymorphism (rs2569190) in the promoter region of the CD14 receptor gene has been reported to be associated with a higher risk of MI. Others studies, however, have not corroborated these findings. Considering the contradictory results, the aim of the present study was to investigate the possible association between the CD14 C(-260)T polymorphism and the risk of MI in the Tunisian population. A total of 321 Tunisian patients with MI and 344 healthy controls were included in the study. Genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. The frequency of TT homozygous genotype for the CD14 C(-260)T polymorphism was 26.2% in MI patients and 27.0% in the control group. However, the genotype distribution and allele frequencies were not significantly different between MI and controls subjects. Moreover, the odds ratio for MI associated with the TT genotype failed to reach statistical significance (OR=1.22; 95% CI: 0.85-1.77; p=0.272). These results do not support the hypothesis that the C-260T polymorphism of CD14 gene contributes to the genetic susceptibility to MI in the Tunisian population studied.

Left main coronary artery thrombosis revealing angio-Behçet syndrome

Although acute myocardial infarction commonly results from coronary atherothrombosis, there are several other etiologies that should be taken initially into account, especially in young adults without significant atherosclerotic risk factors. Thrombophilia and coronary arteritis are, in this context, examples of etiologies that should be looked after. Through this article, we present a case of Behçet′s disease with arterial involvement diagnosed after myocardial infarction resulting from thrombosis of the left main coronary artery in a 38-year-old young man without any particular past medical history.

Polymorphisms in the CC-chemokine receptor-2 (CCR2) and -5 (CCR5) genes and risk of myocardial infarction among Tunisian male patients.

OBJECTIVES The aim of the present study was to investigate the association between CCR2-Val64Ile and CCR5-Δ32 variants and the estimation of haplotypes with MI in a sample of the Tunisian population. DESIGN AND METHODS A total of 290 unrelated MI patients and 282 healthy controls were studied. The CCR2-Val64Ile and CCR5-Δ32 variants were analyzed by PCR-RFLP. RESULTS Subjects carrying at least one copy of the CCR5-deletion allele were significantly more common in the control group, suggesting an atheroprotective effect (adjusted OR=0.44, 95% CI=0.28-0.72, p=0.001). Haplotype analysis showed that MI patients had significantly less 64Val-Del haplotype (9.9% vs. 21.3%, OR=0.30, 95% CI=0.21-0.43, p<0.001) and 64Ile-Ins haplotype (12.3% vs. 16.7%, OR=0.58, 95% CI=0.42-0.80, p<0.001). CONCLUSION A protective effect of the CCR5-Δ32 polymorphism against MI in the Tunisian population was found.

Coronary angiogram video compression adapted to medical imaging applications

H.264/AVC coder has proven to use the most advanced video compression, but, at the cost of high computational complexity. On the other hand, analysis of coronary x-ray images reveals large areas containing no diagnostically important information. In this paper, we propose to exploit the energy characteristics in slice equal size regions to determine the active zones in coronary x-ray sequences to be encoded as normal using the H.264 coding system. The other regions, are compressed using conventional low complex approaches. Experimental results have shown that this procedure reduces the coder computing time of about 20% while attaining the same compression performance. A clinical subjective assessment by three expert physicians in interventional cardiology leads to a compression ratio of about 30:1 which insures both a diagnosis adequacy and a sufficient compression in regards to storage and transmission requirements.

Design and Rationale of the National Tunisian Registry of Atrial Fibrillation: Protocol for a Prospective, Multicenter Trial

Background Atrial fibrillation (AF) is an important health problem in Tunisia. A significant change in the epidemiological pattern of heart disease has been seen in the last 3 decades; however, no large prospective multicenter trial reflecting national data has been published so far. Robust data on the contemporary epidemiological profile and management of AF patients in Tunisia are limited. Objective The aim of this study is to analyze, follow, and evaluate patients with AF in a large multicenter nationwide trial. Methods A total of 1800 consecutive patients with AF by electrocardiogram, reflecting all populations of all geographical regions of Tunisia, will be included in the study, with the objective of describing the epidemiological pattern of AF. Patients will be officially enrolled in the National Tunisian Registry of Atrial Fibrillation (NATURE-AF) only if an electrocardiogram diagnosis (12-lead, 24-hour Holter, or other electrocardiographic documentation) confirming AF is made. The qualifying episode of AF should have occurred within the last year, and patients do not need to be in AF at the time of enrollment. Patients will be followed for 1 year. Incidence of stroke or transient ischemic attack, thromboembolic events, and cardiovascular death will be recorded as the primary end point, and hemorrhagic accidents, measurement of international normalized ratio, and time in therapeutic range will be recorded as secondary end points. Results Results will be available at the end of the study; the demographic profile and general risk profile of Tunisian AF patients, frequency of anticoagulation, frequency of effective treatment, and risks of thromboembolism and bleeding will be evaluated according to the current guidelines. Major adverse events will be determined. NATURE-AF will be the largest registry for North African AF patients. Conclusions This study would add data and provide a valuable opportunity for real-world clinical epidemiology in North African AF patients with insights into the uptake of contemporary AF management in this developing region. Trial Registration ClinicalTrials.gov NCT03085576; https://clinicaltrials.gov/ct2/show/NCT03085576 (Archived by WebCite at http://www.webcitation.org/6zN2DN2QX) Registered Report Identifier RR1-10.2196/8523