Diurnal variation in lipoprotein-associated phospholipase A(2) (Lp-PLA(2))

ObjectivesThe aim of our study was to determine the diurnal variation of lipoprotein-associated phospholipase A₂ (Lp-PLA₂), an arterial-specific inflammatory enzyme implicated in the formation of vulnerable, rupture-prone plaque that can identify individuals at high risk for cardiovascular disease. Presently, the diurnal variation of Lp-PLA₂ is not known.Design and MethodsTen men and 8 women (age range: 22–76 years) had a blood sample taken every 4 h over a 24-hour time period. Samples were analyzed for both Lp-PLA₂ mass and activity.ResultsThe mean coefficient of variation (CV) for Lp-PLA₂ mass was 5.9% (ranges from 2.5 to 9.4%) for the 18 subjects. Similarly, the mean CV for Lp-PLA₂ activity was 3.7% (ranges from 1.2 to 6.8%). There were no significant correlations between CV and any of the subject characteristics.ConclusionsThe diurnal variation of Lp-PLA₂ mass and activity is similar to that of well accepted lipoprotein risk factors. With the relatively low diurnal variability, there does not appear to be a need to make sure serial measurements of Lp-PLA₂ mass and activity are taken at the same time of the day.     

Evaluation of Effects of Intra aortic Balloon Counterpulsation on Autonomic Nervous System Functions by Heart Rate Variability Analysis

Background: In patients with acute myocardial infarction (AMI), intraaortic balloon counterpulsation (IABC) may improve cardiac performance, decrease the incidence of recurrent ischemia, and improve survival. Although there have been several reports concerning circulatory maintenance with the IABC, response of the autonomic nervous system to these hemodynamic changes is not clear. Heart rate variability (HRV) analysis has been extensively used to evaluate autonomic modulation of sinus node and to identify patients at risk for an increased cardiac mortality. In this study, we evaluated effects of the IABC on autonomic nervous system functions by HRV analysis. Methods: The study group was composed of 32 consecutive patients (13 female, 19 male aged 61.8 ± 8.8 years) undergoing IABC. Transthoracic echocardiography and 1‐hour Holter recordings for HRV analysis in each IAB pumping mode were obtained. Results: The IABC improved left ventricular diastolic and systolic functions as well as caused an increase in SDNN1, PNN50(1), RMSSD1, and HF1 and a decrease in LF1, LF/HF1, mean heart rate, and the number of ventricular extrasystoles. The improvements in HRV parameters were correlated with some hemodynamic changes such as the increase in MAP and CO during counterpulsation. The only independent factors affecting in‐hospital mortality were the change in LF/HF1 ratio (ΔLF/HF1) and the change in the number of ventricular extrasystole (ΔVES). The decrease in LF/HF1 ≥4.9 decreased the mortality by 1.7‐folds (RR = 0.6, P = 0.04, 95% CI: 0.1–2.3). The decrease in VES ≥27/15 minutes resulted in mortality reduction by 16‐folds (RR = 0.06, P = 0.02, 95% CI: 0.01–0.4). Conclusions: As a result, the IABC, especially in 1:1 support, causes an increase in HRV, decrease in sympathetic overactivity, and improvement in sympathovagal balance besides the favorable hemodynamic changes, and these electrophysiologic changes may explain the role of the IABC in the treatment of ventricular arrhythmias.     

Relation between sympathetic overactivity and left atrial spontaneous echo contrast in patients with mitral stenosis and sinus rhythm

BACKGROUND: Spontaneous echo contrast (SEC) is common in patients with mitral stenosis (MS) and presence of SEC in left atrium (LA) is associated with a higher risk of thromboembolism. Recently, an increase in activation of platelets was demonstrated in patients with SEC raising the hypothesis that platelets are involved in the pathogenesis of SEC. In this study, we evaluated effects of autonomic nervous system activity on SEC formation in patients with rheumatic MS and sinus rhythm by heart rate variability analysis. METHODS AND RESULTS: Twenty-six patients with LASEC were compared with 28 patients without LASEC. Mean heart rate, low frequency (LF) and low frequency/high frequency (LF/HF) ratio were significantly higher, standard deviation of all NN (SDNN), root mean square of successive differences (RMSSD), number of NN intervals that differed by more than 50 ms from adjacent interval divided by the total number of all NN intervals (PNN50) and high frequency (HF) values were lower in the patients with LASEC. A standard deviation of all NN intervals <90ms separated the patients with LASEC from control subjects with a sensitivity of 77% and specificity of 90%; a low frequency >79.5 with a sensitivity of 92% and specificity of 90; a low frequency/high frequency ratio >3.7 with a sensitivity of 96% and specificity of 90%. A left atrial diameter >4.3 cm increased the LASEC formation by 3.0 folds, HR >78 beats/min by 6.4 folds, standard deviation of all NN intervals <90 ms by 9.2 folds, a low frequency/high frequency ratio >3.7 by 6.4 folds, sP-selectin>142 by 5.8 folds. Variables affecting sP-selectin levels were LA diameter, mitral valve area, transmitral mean gradient, left ventricular ejection fraction, the presence of mitral regurgitation, HR, standard deviation of all NN intervals, low frequency, high frequency and low frequency/high frequency ratio. CONCLUSION: Sympathetic overactivity and reduced heart rate variability are important determinants for LASEC formation and increased s-P selectin levels. Therefore, platelet activation via increased sympathetic activity may play an important role in pathogenesis of LASEC.     

Evaluation of the clinical presentations in neurobrucellosis.

BACKGROUND: Brucellosis is a multisystem disease that may present with a broad spectrum of clinical manifestations and complications. Neurobrucellosis is one of the complications. METHODS: In this study, we describe our experience in the diagnosis, treatment, and the final outcomes of 20 patients with neurobrucellosis out of 305 patients with brucellosis, within a five-year period between January 1999 and June 2004. RESULTS: The rate of neurobrucellosis was 6.6%. Twelve males and eight females with a mean age of 37.4 years were investigated. Fever, headache, confusion, and gait disorders were the main complaints. The duration of their complaints varied between one week and six months. On physical examination, 13 patients had fever, six had neck stiffness and confusion, three had motor deficit on either their upper or lower extremities, and four of them had diplopia. The Rose-Bengal test and standard tube agglutination tests were positive in all of the patients. Brucella melitensis was isolated from the blood of six of the 20 (30%) patients. Cerebrospinal fluid (CSF) was analyzed in 18 patients. Pleocytosis with a mean value of 244x10(6)cells/L, and high protein levels were detected in all. A low glucose level in the CSF was detected in ten patients. Patients were treated medically and a complete resolution was achieved in all. CONCLUSION: Patients with a Brucella infection occasionally manifest central nervous system involvement. Clinicians, especially serving in endemic areas or serving patients coming from endemic areas should consider the likelihood of neurobrucellosis in the patients with unexplained neurological and psychiatric symptoms, and should perform the necessary tests on blood and CSF.     

Aortic dissection with diastolic prolapse of intimal flap into left ventricle.

Ascending aortic dissection is often a catastrophic condition. Dissection into the commissures or into an aortic valve leaflet may lead to leaflet avulsion and valvular insufficiency due to a flail valve. We present an image report describing an important and life-threatening complication due to the movement of a partially dehisced intimal aortic flap into the left ventricle causing aortic valve insufficiency in a patient with acute dissection of the ascending aorta.     

Clinical and angiographic features of large left main coronary artery aneurysms

Coronary artery aneurysms are defined as coronary dilatations which exceed the diameter of normal adjacent segments by 1.5 times. Left main coronary artery (LMCA) is the least frequently involved artery with a prevalence of 0.1%. Majority of coronary artery aneurysms are atherosclerotic in origin. Their size and clinical presentation is variable. A number of complications have been reported to occur during the course of the disease including thrombosis and distal embolization, myocardial ischemia and/or infarction, dissection, vasospasm, calcification, fistulization and very rarely rupture. Large aneurysms of LMCA represent a potentially fatal condition even without concomitant atherosclerotic coronary disease. Because of rarity of coronary artery aneurysms, it is difficult to standardize treatment. In this article, we presented 4 cases of large LMCA aneurysms with various clinical and angiographic features.     

The role of valvular and thoracic aortic calcifications in distinction between ischemic and nonischemic cardiomyopathy

Determination of underlying etiology in patients with dilated and globally hypokinetic left ventricles may sometimes be difficult even after detailed history and complete clinical evaluation. Cardiac valvular and thoracic aortic calcifications have previously been reported to be used as a window to diffuse atherosclerosis of the vascular system. The authors prospectively examined the predictive value of mitral annular calcification (MAC), aortic valve calcification (AVC), and thoracic aortic calcification (TAC) in diagnosis of coronary artery disease as the underlying cause of diffuse left ventricular dilatation and systolic dysfunction. The study included 98 consecutive patients (male/female = 76/22, mean age = 58.9 +/- 10.7 years, range: 33 to 75 years) over the age of 30 years admitted to their clinics between October 1999 and December 2001 with signs and symptoms of congestive heart failure associated with documented cardiomegaly. Transthoracic echocardiography and coronary angiography were performed in all patients for the evaluation of valvular calcifications and coronary status. Although there was no significant difference between the groups with and without coronary artery stenosis (CAS), with regard to presence of MAC, patients with CAS tended to have MAC more frequently (12/61, 20% vs 4/37, 11%, p > 0.05). AVC and TAC were found to be significantly more frequent in patients with CAS compared to those without CAS (AVC, 35/61, 57% vs 4/37, 11%, p < 0.001 and TAC, 28/61, 46% vs 2/37, 5%, p < 0.001). While all 3 calcifications had sensitivity under 60%, and specificity and positive predictive value over 75% individually, the presence of any of them had a sensitivity of 80%, specificity of 86%, positive predictive value of 91%, and negative predictive value of 73%. Thus the presence of any of these calcifications distinguished patients with coronary artery disease with a sensitivity of 80% and specificity of 86%. The presence of aortic valvular valve and thoracic aortic calcifications seems to be associated with significant coronary arterial stenosis; however, with relatively low negative predictive values these cannot be used in clinical practice for diagnosis of underlying coronary artery disease in patients with dilated left ventricles and impaired systolic functions.     

Electrocardiographic changes after coronary artery surgery

The electrocardiographic changes early after uncomplicated coronary artery bypass with complete revascularization were examined preoperatively and on the 1st and 3rd postoperative days in 53 patients. Heart rate, PR index, corrected PR interval, corrected P dispersion, corrected duration of QRS complex, corrected QT dispersion, corrected QT interval, rhythm, QRS axis, ST-segment changes, and blocks were determined. Changes in new parameters obtained by different combinations of R, S, and T waves were also studied. On the 1st postoperative day, atrial fibrillation was significantly less prevalent, right bundle branch block increased significantly, and QRS axis was significantly more positive but returned to baseline on the 3rd postoperative day. Postoperative heart rate and PR index were significantly higher than preoperative values. In the postoperative period, corrected PR interval was significantly lower, corrected QRS complex duration was significantly shorter, corrected QT interval was significantly longer, and corrected QT dispersion showed a significant increase on the 1st postoperative day. This study defines electrocardiographic changes in uncomplicated patients with complete revascularization. Any deviations from these findings may alert us to the need for further evaluation of an undesired event.     

A Simple Different Method to Use Proximal Isovelocity Surface Area (PISA) for Measuring Mitral Valve Area

Background Angle-correction is an important limiting factor for using proximal isovelocity surface area (PISA) method in measuring mitral valve area (MVA). In this study, we derived a novel formula, which simplifies the angle-correction, and tested its use in patients with mitral stenosis (MS). MethodsThe study included 30 MS patients without concomitant aortic or mitral regurgitation. We used mathematical equations and established a relation between the angle and its corresponding border, ‘a’, by using linear regression analysis. It was found that MVA is equal to [(1.11*a² + 0.95)* r² (V_al/V_max)]. We compared this formula with plain angle-corrected and solid angle-corrected PISA methods, planimetry (reference method) and pressure-half time method by linear regression analysis. Results All methods were in significant relation with the reference method, two-dimensional planimetry. We found that there is a good relation between our method and planimetry (r = 0.79, p < 0.001), pressure half-time method (r = 0.85, p < 0.001), angle-corrected PISA method (r = 0.99, p < 0.001), and solid angle-corrected PISA method (r = 0.88, p < 0.001). The time duration of the new method was shorter (p < 0.001). ConclusionOur method is an easy way for applying angle-corrected PISA method to mitral valve area measurement in patients with mitral stenosis. Absence of the need for estimating the angle is the major advantage.     

Diagnosis and treatment of gallbladder perforation

INTRODUCTION Gallbladder perforation (GBP) is a rare but life threatening complication of acute cholecystitis. Sometimes GBP may not be different from uncomplicated acute cholecystitis with high morbidity and mortality rates because of delay in diagnosis[…