Association between endothelial nitric oxide synthase gene polymorphism (-786T>C) and interleukin-6 in acute coronary syndrome

Atherosclerosis is morphologically an inflammatory disease, where endothelial dysfunction plays a key role in all the stages. The nitric oxide (NO) synthase 3 (NOS3) gene is responsible for the synthesis of endothelial NO synthase (eNOS) in humans and some genetic polymorphisms are considered "polymorphisms associated with risk" for the development of coronary artery diseases, such as acute coronary syndrome. Thus, the present study aimed to evaluate the influence of the -786T>C polymorphism of the eNOS gene on inflammatory and oxidative process. A prospective cohort study of 125 consecutive patients with clinical diagnosis of non-ST-elevation acute coronary syndromes was conducted. Patients were assessed using a standardized questionnaire. Blood samples were drawn to measure serum levels of high-sensitivity C-reactive protein, soluble CD40 ligand, interleukin-6 (IL-6), N-terminal prohormone of brain natriuretic peptide, immunoglobulin G antibodies against oxidized low-density lipoprotein. The genotypes for the -786T>C polymorphism in the 5'-flanking region of eNOS gene were determined. The -786C allele was found in 92 of 250 alleles (38.8%). No statistical association was observed between demographic and clinical characteristics and distribution of eNOS-786T>C polymorphism. We found that -786CC was associated with lower levels of IL-6. No significant differences were observed between the distribution of -786T>C polymorphism and other investigated markers.

Anti-beta2-glycoprotein I autoantibodies and metabolic syndrome

BACKGROUND

The metabolic syndrome (MetS) is a proatherogenic entity. Autoantibodies to phospholipid cofactors such as beta2-glycoprotein I (beta2-gpI) can influence atheroma appearance. Previous studies confirmed an association of IgA anti-beta2-gpI antibodies with cerebral ischemia, myocardial infarction, peripheral artery disease and carotid disease.

OBJECTIVE

This case-control study evaluates a possible association of anti-beta2-gpI and anticardiolipin (aCL) antibodies with non-complicated MetS.

METHODS

Cases comprised patients with MetS without history of vascular events; controls included individuals from the Orthopedic Infirmary admitted due to musculoskeletal disorders. Age, sex, race, history of hypertension, smoking, hypercholesterolemia and diabetes mellitus were evaluated as risk factors in both groups. IgG, IgM, and IgA anti-beta2-gpI and aCL antibodies were detected by enzymatic immunoassay.

RESULTS

Sixty-eight patients with MetS and 82 controls were studied. Patients with MetS showed mean age higher than controls (P = 0.001), while males (P = 0.003; OR 0.31; 95%CI 0.15-0.16) and Caucasian ethnicity (P = 0.004; OR 0.25; 95%CI 0.10-0.60) predominated in controls. History of hypertension, hypercholesterolemia and diabetes mellitus were more prevalent in cases than in controls (P < 0.05). The frequency of aCL antibodies (all isotypes) and of IgG and IgM anti-beta2 gpI did not significantly differ in cases and controls. IgA anti-beta2-gpI antibodies were significantly more frequent in MetS patients (42.2%) than controls (10.9%) (P < 0.001). The adjusted OR for IgA anti-beta2-gpI antibodies was 3.60 (95%CI 1.55-8.37; P = 0.003).

CONCLUSION

The current study shows that elevated levels of IgA autoantibodies to β2-gpI might be independently associated to MetS.

Association between interleukin-1 beta polymorphism (+3953) and obesity

It now appears that obesity is associated with a low-grade inflammation of white adipose tissue resulting from chronic activation of the innate immune system as interleukin-1 beta (IL-1). Previous investigations have described a positive association between IL-1 beta +3953 (C>T) gene polymorphism (rs 1143634) and obesity, suggesting functional effects on fat mass, fat metabolism and body mass. However, it is necessary to determine if these results occur in other populations and if they are influenced by sex and age. Therefore, we performed a case-control study using 880 Caucasian subjects (59.7+/-11.9 years old) from the Brazilian Aging Research Program (non-overweight=283, overweight=334, obese=263) previously investigated in genetic studies, in whom we analyzed the IL-1 beta +3953C/T polymorphism. We observed higher T allele (CT/TT) frequency in non-overweight than overweight and obese groups. The odds ratio showed 1.340 (95% CI: 1.119-1.605) times more chance of the obese group being CC carriers compared to non-overweight group independent of sex and age. This study corroborates the idea that the IL-1 system is linked to the development of obesity.

N-acetylcysteine does not prevent contrast induced nephropathy after cardiac catheterisation with an ionic low osmolality contrast medium: a multicentre clinical trial

OBJECTIVE

To evaluate oral N-acetylcysteine in the prevention of contrast induced nephropathy (CIN) in patients at low to moderate risk undergoing cardiac catheterisation with ionic low osmolality contrast medium.

METHODS

In a multicentre double blind clinical trial 156 patients undergoing coronary angiography or percutaneous coronary intervention with serum creatinine > or = 106.08 micromol/l or creatinine clearance < 50 ml/min or diabetes mellitus were randomly assigned to receive N-acetylcysteine 600 mg orally twice daily for two days or placebo. Only low osmolality ionic contrast medium was used.

RESULTS

Sixteen patients developed CIN, defined as an increase of 44.2 micromol/l in creatinine in 48 hours: eight of 77 patients (10.4%) in the N-acetylcysteine group and eight of 79 patients (10.1%) in the placebo group (p = 1.00). The mean (SD) change in serum creatinine was similar in both groups: 7.96 (35.36) micromol/l in the N-acetylcysteine group and 6.19 (25.64) micromol/l in the placebo group (p = 0.67). No difference was observed in the change in endogenous creatinine clearance (-0.54 (10.4) ml/min v -2.52 (12.3) ml/min, N-acetylcysteine and placebo, respectively, p = 0.28).

CONCLUSION

Oral N-acetylcysteine did not prevent CIN in patients at low to moderate risk undergoing cardiac catheterisation with ionic low osmolality contrast medium.

Anti-beta2-glycoprotein I antibodies as risk factors for acute myocardial infarction

OBJECTIVE

To determine whether high levels of antibodies against the phospholipid beta2-glycoprotein I (beta2-gpI) cofactor are associated with an increase in the risk of acute myocardial infarction.

METHODS

The study comprised 82 patients with acute myocardial infarction and 82 controls, who were assessed in regard to age, sex, race, hypertension, smoking, previous heart disease, history of diabetes mellitus, and hypercholesterolemia. The following antibodies were detected using immunoassay: anticardiolipin and anti-beta2-gpI IgA, IgG, and IgM. Adjusted odds ratios (OR) for risk factors were obtained through logistic regression.

RESULTS

The mean ages of the cases and controls were, respectively, 57.7 and 51.1 years (P=0.003). Men (P=0.005) and the white race predominated in both groups (P=0.798). Of the risk factors, a history of diabetes (OR=5.3; 95% CI: 1.9 to 14.9; P=0.001) and previous heart disease (OR=4.7; 95% CI: 2.0 to 10.7; P<0.001) were the most consistent associations with myocardial infarction. The frequency of anticardiolipin IgG, IgM, and IgA antibodies did not differ between cases and controls (P=1.000). Anti-beta2-gpI IgA antibodies were more frequent in cases than in controls (P=0.054). The adjusted OR for anti-beta2-gpI IgA antibodies was 3.4 (95% CI: 1.3 to 9.1; P=0.015).

CONCLUSION

Anti-beta2-gpI IgA antibodies, but not anticardiolipin antibodies, seemed to behave as independent risk factors for myocardial infarction, which may represent a link between autoimmunity and atherosclerosis in patients with acute myocardial infarction.

Polymorphism of 5HT2A serotonin receptor gene is implicated in smoking addiction

Smoking behavior is influenced by genetic factors. Polymorphisms affecting the dopaminergic system have been linked to smoking habits. The aim of this study was to investigate if the T102C polymorphism of the 5-HT(2A) receptor gene is related to tobacco use, since this receptor modulates the mesolimbic dopamine system and the C allele is associated with reduced receptor gene expression. A sample of 625 subjects were genotyped and classified according to their smoking behavior (never, former, or current smokers). We found differences in the distribution of the genotypes when the current smokers were compared with the never + former smokers, suggesting that T102C polymorphism is associated with maintenance, but not with initiation of the smoking habit. The CC genotype was more frequent in the current smokers than in the never + former smokers (chi(2) = 6.825, P = 0.03). The odds ratio of being a current smoker with a CC genotype was 1.63, 95% CI 1.06-2.51.

Cardiopulmonary resuscitation: update, controversies and new advances

Cardiopulmonary arrest is a medical emergency in which the lapse of time between event onset and the initiation of measures of basic and advanced support, as well as the correct care based on specific protocols for each clinical situation, constitute decisive factors for a successful therapy. Cardiopulmonary arrest care cannot be restricted to the hospital setting because of its fulminant nature. This necessitates the creation of new concepts, strategies and structures, such as the concept of life chain, cardiopulmonary resuscitation courses for professionals who work in emergency medical services, the automated external defibrillator, the implantable cardioverter-defibrillator, and mobile intensive care units, among others. New concepts, strategies and structures motivated by new advances have also modified the treatment and improved the results of cardiopulmonary resuscitation in the hospital setting. Among them, we can cite the concept of cerebral resuscitation, the application of the life chain, the creation of the universal life support algorithm, the adjust-ment of drug doses, new techniques--measure of the end-tidal carbon dioxide levels and of the coronary perfusion pressure--and new drugs under research.

[Use of high-dose oral amiodarone for the reversion of atrial fibrillation during the postoperative period of cardiac surgery]

PURPOSE

To report our experience using high dose oral amiodarone (1,800 mg/day) for the reversion of atrial fibrillation to sinus rhythm in patients submitted to cardiac surgery.

METHODS

We retrospectively analyzed the records of 80 patients who had atrial fibrillation during the postoperative period after cardiac surgery, initially divided in two groups: group A, 28 patients that used amiodarone, and group B composed of patients receiving digoxin. The latter group was divided further in a third group (C), with 21 patients in which amiodarone was associated with digoxin if there was no reversion of the arrhythmia after 48 hours of treatment. The observed differences were considered significant at P < 0.05.

RESULTS

Atrial fibrillation occurred in 19.4% of the patients submitted to surgery, predominating in males, 60 to 69 years-old. In group A there was reversion to sinus rhythm in 78.6% of the cases. In group B digoxin succeeded in 60%, and in group C 90% of the patients reverted to sinus rhythm.

CONCLUSION

High dose oral amiodarone, alone or combined to digoxin, can be safe and effective for the treatment of atrial fibrillation after cardiac surgery.

[When does the treatment with captopril show a better improvement in physical performance in patients with heart failure?]

PURPOSE

Considering that heart failure reduces exercise capacity and that converting enzyme inhibitor increases this capacity, using the 6 min walk test we try to demonstrate when the treatment with captopril shows a better improvement in exercise capacity in patients with heart failure.

METHODS

Twenty one patients with functional class II or III heart failure (NYHA), left ventricular diastolic diameter greater than 55 mm and with ejection fraction less than 45% were studied. Twelve were male, and the patients mean age was 48 years. The patients were first treated with digital and diuretics and after stabilized they received captopril 25 mg three times a day and underwent the 6 min walk test before the treatment and after four and 16 weeks.

RESULTS

The use of captopril showed important improvement in exercise capacity in patients with heart failure. The mean walking distance on the 6 min test was 451 m at the beginning, 476 m in four weeks and 504 in 16 weeks of treatment (p < 0.0001).

CONCLUSION

Our data show important improvement in exercise capacity with 16 weeks of treatment and that 50% of this improvement occurred after four weeks of treatment. We concluded that the results are already observed within four weeks of treatment and continues to improve during at least four months of treatment.

[Etiology of left bundle branch block in Porto Alegre]

PURPOSE

To determine the type of cardiac disease causing left bundle branch block (LBBB) in Porto Alegre, Brazil, and to assess the role of associated left axis deviation (-30 degrees or more in the frontal plane) in order to identify a specific etiology of LBBB.

METHODS

Through reports from the assistant physicians or through examination of the patients, the underlying heart disease in 264 cases of LBBB was assessed. The chi-square test was used to determine a possible association between left anterior hemiblock LBBB and one or more specific type of underlying heart disease.

RESULTS

Systemic arterial hypertension (30.7%), ischemic heart disease (30.3%), valvar heart disease (8.7%), cardiomyopathies (7.5%), idiopathic degenerative disease of the conduction system (1.6%) and miscellaneous heart diseases (1.2%) were the underlying heart diseases. The presence of LBBB did not indicate any specific type of cardiac disease.

CONCLUSION

The causes of LBBB in Porto Alegre are the same as reported in the international medical literature. Upward and leftward deviation (> or = -30 degrees) of QRS axis in the frontal plane did not show statistical significant association with any type of underlying cardiac disease.

[Evaluation of post-intracoronary stent implant. Intravascular ultrasound versus quantitative angiography]

PURPOSE

To verify the minimal proximal and distal residual diameters by quantitative digital angiography and intravascular ultrasound, after the implantation of the intracoronary prosthesis.

METHODS

We studied twenty patients with coronary atherosclerosis, ages ranging from 40 to 77 (56.7 +/- 10) years, 13 (65%) were male. Patients with eccentric obstructive atherosclerotic lesions of 70% or more in the proximal third of the anterior descendent, circumflex, or right coronary arteries received a stent implant as treatment for the obstruction.

RESULTS

The mean proximal minimal residual diameters assessed by digital angiography were 3.32 +/- 0.33 mm and by ultrasound 3.08 +/- 0.31 mm (p < 0.05); the distal diameters by angiography were 3.33 +/- 0.37 mm and by ultrasound 3.05 +/- 0.39 mm (p < 0.05). Therefore, the measurements by ultrasound were always smaller. There is a significant linear correlation between measurements by angiography and ultrasound for both proximal (r = 0.92; p < 0.0001) and distal diameters (r = 0.91; p < 0.0001). The determination coefficient was 84% for proximal diameters and 87% for distal diameters. Therefore, the proximal diameters variate 16% and distal diameters 13% between both methods, due to the peculiarities of each method.

CONCLUSION

Both methods correlate adequately, concerning to the measurements; the methods are interdependent, determining with the same accuracy intracoronary diameters in most cases studied; ultrasound is a safe and feasible technical resource for the evaluation of intravascular structures; the intravascular ultrasound system can contribute for the direct analysis inside the vascular structure, immediately after intracoronary stent implanting.

[Exercise capacity evaluation in patients with mild to moderate left ventricular dysfunction. Influence of captopril]

PURPOSE

To analyse the captopril influence on physical activity on the six or nine minute walk test in patients with left ventricular dysfunction and mild or moderate failure.

METHODS

Twenty one patients with functional class II or III heart failure and left ventricular diastolic diameter greater than 55 mm and with ejection fraction less than 45% were studied. Twelve were male, and the patients age range from 34 to 63 years old (mean 48 years). The protocol has 18 weeks of duration, the first two weeks constitute a washout period, and 16 of effective use of captopril 25 mg tid. The patients were submitted to clinical and laboratory evaluations, to echocardiogram study and six and nine minute walk test (distance of walk), before, through out, and after the protocol.

RESULTS

The distance of walk on six minute test were 451 m at the beginning, and 476 m in 4 weeks and 504 m at 16 weeks of treatment (p < 0.0001). At nine minute test it was respectively 599, 652 and 692 m (p < 0.001). The echocardiographic evaluation showed significative reduction of the left ventricular diastolic diameter and an increase of the left ventricular ejection fraction. The clinical evaluation after the treatment showed that 45% comes to functional class I, and only 10% stayed in class III.

CONCLUSION

Captopril 25 mg tid improves clinical performance significantly, with improvement of walk distance at six or nine minute of test, and with reduction of left ventricular end diastolic diameter and systolic function improvement. The results permits to conclude that captopril improves significantly the physical activity of patients with heart failure, this improves were observed with one months of therapy but is more evident with four months of effective treatment.

[Evaluation of QRS voltage in 12 derivations and Cornell criteria in the diagnosis of left ventricular hypertrophy]

PURPOSE

To search for the existence and degree of correlation between total 12 lead ECG amplitude and the sum of RaVL + SV3 > 28 mm (for men) or > 20mm (for women) and left ventricular hypertrophy (LV mass calculated by echocardiography > 215g for both sexes).

METHODS

ECG and echocardiograms of 227 consecutive patients were examined and submitted to statistical analysis searching for correlation between total 12 lead ECG amplitude and Cornell criteria and LV mass (ASE formula modified by Devereux).

RESULTS

Patients had ischemic heart disease, hypertension, valvular disease, cardiomyopathy or other less common heart diseases, or had no cardiac illness at all. There was statistically significant association of total 12 lead amplitude > 120mm and Cornell criteria with LV mass > 215g (p = 0.02 and p = 0.01 respectively). Total ECG amplitude showed 74.3% sensitivity, 42.6% specificity, and 52.4% accuracy. Cornell criteria showed values of 37.8%, 82.7% and 68.7% respectively.

CONCLUSION

Total 12-lead amplitude presented limited diagnostic performance for detecting LV hypertrophy, as well as did ECG Cornell criteria, although the latter was more specific and more accurate.

[Prolonged mechanical ventilation following heart surgery]

PURPOSE

To study the causes of difficulty or impossible weaning of cardiac surgical patients undergoing mechanical ventilation in the postoperative period and their outcome.

METHODS

Three hundred and forty three consecutive adult patients submitted to open heart surgery were retrospectively studied and classified in three groups: I--patients in mechanical ventilation more than 24 hours; II--patients in mechanical ventilation less than 24 hours and reintubated some time after this period; III--patients successfully extubated in the first 24 hours of ventilation.

RESULTS

The authors were able to identify the following preoperative factors associated with prolonged postoperative ventilation: cardiac failure, pulmonary hypertension, smoking, chronic obstructive pulmonary disease and previous open heart surgery. Significant factors in the immediate postoperative period (1st 24 hours) were: atelectasis, low output syndrome, perioperative myocardial infarction, reoperation for excessive bleeding, pleural effusion and cardiac arrest. This group of patients had a significant increase in nosocomial pneumonia, multiple organ failure (MOF) and surgical mortality.

CONCLUSION

Pre and postoperative factors were identified associated with prolonged mechanical ventilation in the postoperative period and responsible by significant morbidity as such pulmonary infection, MOF and increase in mortality.