Risk factors for in-hospital mortality in infective endocarditis: five years' experience at a tertiary care hospital in Turkey.

BACKGROUND AND AIM OF THE STUDY: Despite recent improvements in diagnostic and therapeutic interventions, infective endocarditis (IE) is still associated with high in-hospital mortality rates. The study aim was to determine the clinical, laboratory and echocardiographic features of IE, and to evaluate the risk factors for in-hospital mortality. METHODS: A retrospective cohort study design was employed, with a main outcome measure of in-hospital mortality. A total of 107 patients (79 males, 28 females; mean age 45 +/- 16 years) admitted with the modified Duke criteria for definitive IE were included in the study during a five-year period between January 2004 and December 2008. RESULTS: Among the patients, the mitral valve alone was involved in 45% of cases, the aortic valve in 36%, tricuspid valve in 11%, and multiple valves in 8%. Forty-seven patients (44%) had prosthetic valves. Blood cultures were positive in 71 patients (66%). The most common isolated microorganisms were staphylococci, streptococci and Brucella melitensis. The in-hospital mortality rate was 27%. Leading causes of death were multi-organ failure and heart failure. In univariate analysis, factors associated with death were a longer duration of symptoms before hospitalization, previous history of IE, white blood cell count > or = 10,000/mm3, serum creatinine level > or = 2 mg/dl, vegetation size >15 mm, involvement of multiple valves, existence of severe regurgitation, cardiac abscess, and neurologic complications. Multivariate analysis showed that risk factors for mortality were multivalvular involvement (hazard ratio (HR) 4.7; 95% confidence interval (CI) 1.3-17.6; p = 0.021), vegetation size >15 mm (HR 5.5; 95% CI 2.1-14.6; p = 0.001), serum creatinine > or = 2 mg/dl (HR 4.1; 95% CI 1.8-9.4; p = 0.001), and previous history of IE (HR 3.5; 95% CI 1.2-11; p = 0.026). CONCLUSION: Multivalvular involvement, vegetation length >15 mm, serum creatinine level > or = 2 mg/dl on admission, and a previous history of IE, were independent predictors for in-hospital mortality in IE.

Coronary artery to left ventricular fistula demonstrated by transthoracic echocardiography.

Coronary artery fistulas are rare coronary anomalies which generally require coronary angiography for definitive diagnosis. Improvements in ultrasound technology has enabled direct, transthoracic visualization of long portions of coronary arteries. We report a patient with a symptomatic coronary to left ventricular fistula, which was diagnosed with transthoracic echocardiography.

[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.

The effects of mobile phones on pacemaker function.

OBJECTIVES: The electromagnetic field generated by different systems have well-recognized adverse effects on pacemaker functions. The aim of this study is to evaluate the adverse effects of mobile phones on pacemaker functions. METHODS AND RESULTS: A total of 679 patients with permanent pacemakers were enrolled in this study. The study was performed in two steps. Pacemaker lead polarity was unipolar in the first step and bipolar in the second step. Pacemaker sensitivity was first at nominal values, it was then reduced to the minimal value for that pacemaker and tested again. Two mobile phones were symmetrically located on both sides of the pacemaker pocket with the antennas being equidistant at 50, 30, 20 and 10 cm and in close contact with the pocket. The tests were performed when both mobiles were opened, on stand-by, were receiving a call, during the call and were closed. Thirty-seven patients with pacemakers were adversely affected (5.5%) (33 VVI-R pacemakers were converted to asynchronous mode, and 3 were inhibited, 1 DDD-R pacemaker developed ventricular triggering). When the lead polarity was unipolar, the rate of adverse effect was higher when compared to the bipolar state (4.12% and 1.40%, p<0.01). The increase in sensitivity was not an independent factor on the rate of being affected (p>0.05). The rate of observing an adverse effect increased as the pacemaker got older (p<0.05). CONCLUSIONS: Mobile phones might have adverse effects on pacemaker functions under certain conditions. This does not result in any symptoms other than the inhibition of pacemakers, and pacemaker functions return to normal when the mobile phones are removed away from the patient.

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.

Right coronary artery originating from distal left circumflex: an extremely rare variety of single coronary artery.

Single coronary artery is a rare congenital anomaly of the coronary circulation which is often associated with other congenital cardiac malformations. Right coronary artery arising from the distal left circumflex artery is an extremely rare variety of single coronary artery. We report a patient with a single coronary artery system, in whom the right coronary artery originated from the distal left circumflex. No other associated cardiac anomaly was detected.

Influence of haematological parameters before coronary angioplasty on subsequent restenosis.

OBJECTIVES: Restenosis is the major limitation of coronary interventions occurring in nearly a third of the patients undergoing percutaneous transluminal coronary angioplasty (PTCA) with no single, definite predictor demonstrated in an individual patient. Platelets are known to play an important role in the pathogenesis of subsequent restenosis. METHODS AND RESULTS: In a prospective study, follow-up coronary angiographies were performed in 102 consecutive patients with stable angina who underwent a successful PTCA for single-vessel coronary artery disease. Demographics, baseline lipid profiles (total cholesterol, HDL- and LDL-cholesterol, triglycerides) and haematological parameters (red cell, white cell and platelet counts, haemoglobin concentration, haematocrite %, mean platelet volume, platelet mass and fibrinogen levels) were compared between patients with and without restenosis. In the restenosis group, mean platelet volume (8.82 +/- 0.78 fl vs. 8.13 +/- 0.64 fl, p < 0.001), white cell count (8673 +/- 322 x 10(3)/microl vs. 7513 +/- 232 x 10(3)/microl, p < 0.01) and fibrinogen level (4.2 +/- 1.4 g/l vs 3.6 +/- 1.1 g/l) were significantly higher. The relative odds for developing angiographically defined restenosis were 2.49 times greater in diabetics (p = 0.11) and 2.54 times greater in men (p = 0.13). It is 1.43 times greater in patients with higher fibrinogen levels (p = 0.16). But, the relative odds for developing restenosis were 10.43 times greater in patients with larger pre-procedural mean platelet volumes (p < 0.01). CONCLUSIONS: There was a positive correlation between mean platelets volume and loss in luminal diameter between post-angioplasty and follow-up angiographies (r = +2.345, p = 0.01). There was no association between restenosis and haemoglobin, haematocrit, red cell count, white cell count, platelet count, platelet mass and plasma fibrinogen level. The development of restenosis after successful coronary angioplasty may be mainly influenced by the platelet size.

Noninvasive evaluation of coronary artery bypass grafts and native coronary arteries: is 16-slice multidetector CT useful?

PURPOSE: To investigate the diagnostic accuracy and limitations of 16-slice multidetector computed tomography (MDCT) in the detection of significant ( > 50%) stenosis of coronary artery bypass grafts (CABG) and native coronary arteries. MATERIALS AND METHODS: One hundred two patients with 236 grafts were investigated by 16-slice MDCT. Native coronary arteries were also investigated. The image quality was assessed in terms of artifact, and the evaluable segments were screened for the presence of occlusion and significant ( > 50%) stenosis. MDCT results were compared with conventional coronary angiography. RESULTS: The evaluability of MDCT was 90.4% for CABG and 71.2% for native coronary arteries. The most frequent causes of nonevaluable segments were motion artifact in venous grafts, metallic clip artifact in arterial grafts, and severe calcification in native coronary arteries. MDCT correctly diagnosed all of the 46 occluded grafts. The sensitivity, specificity, and the positive and negative predictive value of MDCT for the detection of significant CABG stenoses were 91.4%, 98.5%, 84.2%, and 99.2%, respectively. Including nonevaluable segments in the analysis, overall sensitivity was 84.2%. For the evaluation of native coronary arteries, MDCT had a sensitivity of 82.1% and a specificity of 75.3%, but evaluability was only 71.2%, resulting in overall sensitivity of 62.1%. CONCLUSION: Use of 16-slice MDCT angiography allows very accurate evaluation of CABG patency and has high diagnostic accuracy in detecting graft stenoses. But evaluation of native coronary artery stenosis is limited, particularly in patients with advanced coronary artery disease with severe calcification.

Acquired cardiac hypertrophy with outflow tract obstruction in a patient with severe Takayasu arteritis.

Takayasu arteritis with coronary artery involvement is rare and its association with secondary cardiac hypertrophy with severe outflow tract obstruction is not common. We describe a case of Takayasu arteritis, diagnosed 10 years ago, whose coronary artery involvement and obstructive cardiac hypertrophy are ascertained after our investigations.

Giant Left Anterior Descending Artery Aneurysm in a Patient with Behcet's Disease.

Coronary artery aneurysm is a rare coronary abnormality nearly half of which originates from atherosclerotic lesions. The major causes of non-atherosclerotic coronary aneurysms include coronary ectasia, Kawasaki disease, Takayasu aortitis, thoracic trauma and complicated angioplasty; however, it has been rarely reported associated with Behcet's disease.

Evaluation of the early hemodynamic changes in carotid arteries during ventricular and dual chamber pacing.

In spite of a wide choice of pacemakers, there are some problems in making more rational clinical decisions for individual patients since mode selection and programming is usually performed on the basis of a clinical hunch. The aim of this study was to measure the differences in carotid flow in patients with a pacemaker programmed in the dual chamber and in the single chamber pacing modes. Sixty patients with implanted bipolar DDD pacemakers were enrolled in this study. Blood peak systolic velocity (PSV) and end-diastolic velocity (EDV), cross-sectional area, resistive index (RI), and pulsatility index (PI) were measured in the common (CCA), internal (ICA), and external (ECA) carotid arteries before pacemaker implantation and after dual chamber and ventricular pacing at 60 beats/min. PSVs in the left CCA (79.3 +/- 24.9 cm/s) and right CCA (84.1 +/- 18.7) were shown to significantly decrease after VVI pacing (60.1 +/- 16.6 and 62.1 +/- 20.0, respectively). There was also a similar significant decrease in PSV in the left and right ICAs and ECAs. Besides PSV, RI, and PI in the left and right CCAs, ICAs, and ECAs significantly decreased after VVI pacing. There was no similar decrease after DDD pacing. Cross-sectional area and flow volume in the CCA, ICA, and ECA were similar after DDD and VVI pacing and before pacemaker implantation suggesting that cardiac output was similar when the measurements were recorded. Carotid artery PSVs, pulsatility, and RIs were found to be significantly decreased during VVI pacing compared to baseline and DDD pacing. The greater incidence of adverse cerebral outcomes in patients with VVI rather than DDD pacing may be partly due to decreased carotid PSVs.