Myocardial noncompaction presenting with Brucella endocarditis.

Noncompaction of ventricular myocardium is a unique congenital cardiomyopathy with its own clinical presentation and course. It is more frequently associated with complications of congestive heart failure, thromboembolism and malignant ventricular arrhythmias; however, concomitance of valvular pathologies or infective endocarditis with noncompaction of ventricular myocardium has seldom been reported. We describe herein the first case of left ventricular myocardial noncompaction presenting with Brucella endocarditis with aortic and mitral valve involvements, whom subsequently underwent successful medical and surgical treatment.

[The effect of plasma asymmetric dimethylarginine (ADMA) level and L-arginine/ADMA ratio on the development of coronary collaterals]. / Plazma asimetrik dimetilarginin (ADMA) düzeyi ve L-arginin/ADMA oraninin koroner kollateral gelisimi üzerine etkisi.

OBJECTIVES: It has been shown that asymmetric dimethylarginine (ADMA), an endogenous competitive antagonist of nitric oxide (NO) synthase, inhibits angiogenesis by reducing the production and bioavailability of NO. We investigated the effect of plasma ADMA level and L-arginine/ADMA ratio on the development of coronary collateral arteries. STUDY DESIGN: The study consisted of 94 patients (66 males, 28 females; mean age 59+/-11 years) who underwent coronary angiography for suspected coronary artery disease and were found to have severe stenosis (>95%) in at least one major coronary artery. The patients were evaluated in two groups with poor (Rentrop score 0-1, n=44) and good (score 2-3, n=50) coronary collateral circulation according to the Rentrop collateral scoring system. Plasma levels of ADMA and L-arginine were measured by high-performance liquid chromatography. RESULTS: The two groups were similar with regard to basal characteristics and cardiovascular risk factors (p>0.05) except for stable angina, which was more common in patients with Rentrop score 2-3 collateral circulation (p<0.001). Despite similar L-arginine levels (p>0.05), patients with Rentrop score 0-1 had a significantly higher ADMA level (p=0.003) and lower L-arginine/ADMA ratio (p=0.019). Multivariate logistic regression analysis showed that plasma ADMA concentration was an independent predictor of coronary collateral development (odds ratio=0.674; 95% confidence interval=0.508-0.894; p=0.006). CONCLUSION: Elevated plasma ADMA concentrations are associated with a poorly developed coronary collateral circulation, suggesting that dysregulation of the NO synthase pathway may result in impaired collateral development.

Evaluation of atrial refractoriness immediately after percutaneous mitral balloon commissurotomy in patients with mitral stenosis and sinus rhythm.

BACKGROUND: Chronic atrial stretch and rheumatic inflammatory activity leads to atrial dilatation and conduction slowing, and this increases the susceptibility to atrial fibrillation (AF). The aim of this study was to examine the effects of changes in the chronic atrial stretch on atrial refractoriness in the early period after percutaneous mitral balloon commissurotomy (PMBC) in patients with mitral stenosis and sinus rhythm. METHODS: Twenty-five patients undergoing PMBC were enrolled in this study. We evaluated the changes in pulmonary arterial pressure (PAP), left atrial (LA) pressure, mean mitral diastolic gradient, and mitral valve area in addition to the changes in atrial effective refractory periods (AERPs), AERP dispersion, and intra-atrial and interatrial conduction times after PMBC. RESULTS: There were significant decreases in mean diastolic gradient, PAP, mean LA pressure, and LA size after PMBC. Accompanying these acute hemodynamic changes after PMBC, AERPs in high right atrium (HRA), distal coronary sinus (DCS), and right posterolateral (RPL) were found to be increased (P <.001), and AERP dispersion, PA(HIS) (an interval between P wave on the surface electrocardiogram and atrial electrogram at the His bundle site), and HRA-DCS intervals were significantly reduced after PMBC (P <.001). It was revealed with linear regression and correlation analysis that only the changes in AERP dispersion were correlated with changes in LA pressure. CONCLUSIONS: Relief of chronic atrial stretch results in an increase in AERPs and decrease in AERP dispersion, suggesting the potential reversibility of the electrophysiological features of chronic atrial dilatation. Our study emphasizes that an acute reduction of chronic atrial stretch in mitral stenosis resulted in favorable effects on atrial electrophysiological characteristics, and our results provide the first detailed insights into the electrophysiological changes after PMBC in patients with sinus rhythm.

Increased dispersion of refractoriness in patients with atrial fibrillation in the early postoperative period after coronary artery bypass grafting.

INTRODUCTION: Increased atrial effective refractory period (AERP) dispersion is well correlated with vulnerability to atrial fibrillation (AF). However, the preoperative electrophysiologic characteristics of atrial abnormalities that may play an important role in the development of AF postoperatively in patients with coronary artery bypass grafting (CABG) have not been investigated in detail. METHODS AND RESULTS: Fifty-six consecutive patients who underwent CABG were enrolled in this study. Eighteen patients (14 men and 4 women; mean age 57.7 +/- 5.2 years) with AF in the early postoperative period and 38 patients (28 men and 10 women; mean age 56.3 +/- 6.4 years) without AF were compared with regard to preoperative clinical, echocardiographic, angiographic, and electrophysiologic parameters. Preoperative PA interval and AERP dispersion values were higher (P < 0.05) in patients who developed AF in the early postoperative period. PA interval (P < 0.05, odds ratio = 1.64, 95% confidence interval 1.17-2.30), AERP in the high right atrium (AERP(HRA); P < 0.05, odds ratio = 0.94, 95% confidence interval 0.91-0.97), AERP in the right posterolateral atrium (AERP(RPL); P < 0.05, odds ratio = 0.79, 95% confidence interval 0.63-0.98), AERP in the distal coronary sinus (AERP(DCS); P < 0.05, odds ratio = 0.84, 95% confidence interval 0.74-1.02), and AERP dispersion (P < 0.001, odds ratio = 1.29, 95% confidence interval 1.12-1.47) were independently related to post-CABG AF in univariate analysis. Increases in preoperative PA interval and AERP dispersion were found to be associated with a high risk for development of post-CABG AF. CONCLUSION: AERP dispersion is a suitable electrophysiologic indicator for atrial vulnerability. The presence of increased preoperative AERP dispersion and PA interval may indicate patients at high risk for development of AF in the early postoperative period after coronary artery bypass grafting.