HPV Infection and Immunohistochemical Analysis of P16, P53, and PD-L1 Expression as Prognostic Biomarkers in Squamous Cell Anal Cancer Patients Receiving Definitive Radiotherapy/Chemoradiotherapy

PURPOSE/OBJECTIVE(S)

The treatment of anal squamous cell carcinoma (SCC) with definitive radiotherapy (RT)/chemoradiotherapy (CRT) has a high likelihood of success; nevertheless, treatment resistance and recurrence rates cannot be ignored. Therefore, we aimed to identify the relationship between immunohistochemical (IHC) evaluation, treatment response, and prognosis.

MATERIALS/METHODS

This retrospective study included 42 patients with anal SCC treated with definitive RT/CRT at a single institution between 2006 and 2020. Detection of high-risk HPV-DNA and IHC analysis of p16, p53, and PD-L1 expression was performed from diagnostic formalin-fixed, paraffin-embedded (FFPE) biopsies. Positive staining was accepted as >5% in tumor cells for p16 and p53 expression in addition to ≥1% combined positive score (CPS) [(PD-L1 positive tumor, lymphocyte, macrophage count/total viable cell count) x100] for PD-L1 expression.

RESULTS

Thirty patients (71.4%) had a complete response to definitive RT/CRT. Recurrence was observed in 16 (38.1%) patients, with 3 (7.1%) having locoregional recurrence (LRR), 6 (14.3%) having distant metastases (DM), and 7 (16.7%) having both LRR and DM. Twenty-four (57.1%) patients were alive. Thirty (71.4%) patients were HPV+, while 12 (28.6%) were HPV-. There was a significant correlation between HPV+ and p16+ status (p<0.001). HPV- status was associated with the male gender (p = 0.001). HPV- and p16- status were significantly associated with a lack of complete response to definitive RT/CRT (p<0.001, p<0.001, respectively). Furthermore, there was a significant relationship between lack of complete response and increased recurrence (p = 0.016) and distant metastases (p = 0.015). Ten of the 16 patients with recurrence were p53+; a significant correlation was found between recurrence and p53+ status (p = 0.006). Similarly, p53+ status was associated with increased LRR (p = 0.014). PD-L1 CPS ≥ 1% was found in 31 (73.8%) patients. PD-L1 positivity was significantly correlated with HPV+ (p = 0.026) and p16+ (p = 0.013) status. All 10 (23.8%) patients with LRR were PD-L1+; PD-L1 CPS ≥ 1% was associated with poor local control (p = 0.031). In univariate analysis, age [<65] (p = 0.049), complete response (p = 0.015), and HPV+ status (p = 0.010) were related to increased 5-year (y) overall survival (OS); complete response (p = 0.001), HPV+ status (p = 0.025) and p53- status (p = 0.010) were associated with increased 5-y disease-free survival (DFS). In multivariate analysis, age [<65] (p = 0.010) and HPV+ status (p = 0.002) were significant prognostic factors for 5-y OS, whereas complete response (p = 0.007) and p53- status (p = 0.038) were significant prognostic factors for 5-y DFS.

CONCLUSION

Patients with HPV- status and/or poor prognostic biomarkers should be identified at diagnosis. Thus, better outcomes can be achieved with different treatment options, such as combining immunotherapy and standard CRT.

Histological, immunohistochemical and biochemical effects of bee bread on stomach tissue of obese rats

Obesity is a major health problem threatening humanity in medical, social and psychological dimensions. In this study, we aimed to determine the histological, immunohistochemical and biochemical effects of bee bread, added to diets of obese rats in different doses, on leptin and ghrelin expression. In the study, 40 female Sprague‒Dawley (200‒250 g) rats were randomly divided into 5 equal groups and then assigned to control and obesity groups. The obesity group consisted of four subgroups: high‑fat diet group, 100 and 200 mg/kg/bw groups, and metformin group. Histopathological evaluation revealed structural deterioration and necrotic areas in the epithelium and glands of the obese rats' stomach tissue, while in their serum and gastric tissues, the MDA level was significantly higher than in the other groups. There was a negative correlation between leptin and ghrelin levels. Apoptotic cells increased with obesity, but the application of beebread was similarly effective as metformin administration in reducing this increase (Tab. 5, Fig. 4, Ref. 51). Keywords: bee bread, leptin, ghrelin, stomach, obesity, rat.

SDN Based End-to-End Inter-Domain Routing Mechanism for Mobility Management and Its Evaluation

Nowadays, due to the widespread usage of mobile devices and wireless network technologies, we can use various ICT services almost anytime, anywhere even if we are changing our location at that moment. Therefore, mobility management technology have been attracting attention. This technology is to keep communication alive even when a mobile node (MN), which is communicating with the server or some nodes, moves to another network domain. Software Defined Networking (SDN) is used for mobility management to realize effective intra-domain routing that optimizes routes when an MN moves inside an SDN domain. However, many of the approaches mainly focus on intra-domain routing and it is difficult to optimize inter-domain route. In this paper, we focus on this routing optimization problem and propose an SDN based end-to-end routing mechanism specified for mobility management. The proposed routing mechanism can optimize an end-to-end route based on various parameters such as bandwidth, number of domains, and flow operations for mobility after an MN has moved across SDN domains. We carried out some simulational experimentations to evaluate the effect of proposal. It is shown that the proposed routing mechanism can reduce communication delay and enhance network performance. Thus, the proposed routing mechanism can realize effective ICT services.

Investigating the coumarin capability in chalcogenide 20TI2Se-80Pr2Se3 system based photovoltaics

Chalcogenide films containing various contents of coumarin (CO) are deposited on the p-type Si substrates. Al/coumarin doped chalcogenide films/p-Si contact exhibits a rectifying behavior. The electrical and photoresponse properties of the prepared diodes are characterized by current and capacitance measurements under various illumination intensities. The addition of coumarin to TI₂Se-Pr₂Se₃ significantly affects the characteristic parameters of diodes. Kohlrausch function is used as an appropriate way to obtain the photo charge density (ρ_ph) and the relaxation time constant from the photocurrent/capacitance transients. It is shown that coumarin doped chalcogenide films have a potential to obtain the photocarrier generation.

Composite CuFe1-xSnxO2/p-type silicon photodiodes

CuFe_1-xSn_xO₂ composite thin film/p-type silicon diodes were prepared on substrate by sol-gel method (x=0.00, 0.01, 0.03, 0.05, 0.07). The structure of CuFe_1-xSn_xO₂ composite thin films was studied using XRD analysis and films exhibited amorphous behavior. The elemental compositions and surface morphology of the films were characterized using SEM and EDX. EDX results confirmed the presence of the compositional elements. The optical band gap of CuFe_1-xSn_xO₂ composite thin films was determined using the optic spectra. The optical band gaps of the CuFe_1-xSn_xO₂ composite thin films were calculated using optical data and were found to be 3.75, 3.78, 3.80, 3.85 and 3.83eV for x=0.00, 0.01, 0.03, 0.05 and 0.07, respectively. The photoresponse and electrical properties of the Al/CuFe_1-xSn_xO₂/p-Si/Al diode were studied. The barrier height and ideality factor were determined to be averagely 0.67eV and 2.6, respectively. The electrical and photoresponse characteristics of the diodes have been investigated under dark and solar light illuminations, respectively. The interface states were used to explain the results obtained in present study. CuFe_1-xSn_xO₂ photodiodes exhibited a high photoresponsivity to be used in optoelectronic applications.

Coagulation, Fibrinolytic System Activation and Endothelial Dysfunction in Patients With Mitral Stenosis and Sinus Rhythm

Anticoagulation treatment can prevent systemic embolism in patients with mitral stenosis (MS) and atrial fibrillation (AF), but this treatment is under debate if patients are in sinus rhythm. The authors aimed to determine the hemostatic changes in patients with MS and sinus rhythm. Forty-six patients (28 in sinus rhythm and 18 in AF) with mitral stenosis were enrolled in this study. They studied systemic venous fibrinogen, D-dimer, antithrombin-III, tissue plasminogen activator (tPA), plasminogen activator inhibitor-I (PAI-I), von Willebrand factor (vWF), and platelet factor 4 (PF 4) in these patients. The patients were first classified according to their rhythm as sinusal and AF, and then according to the presence of left atrial spontaneous echo contrast (LASEC). Fibrinogen, D-dimer, antithrombin-III, vWF, and PF 4 levels were significantly greater in patients with MS and sinus rhythm or atrial fibrillation compared to the control group (p<0.05). Whether the rhythm was sinus or AF, fibrinogen, D-dimer, antithrombin-III, vWF, and PF 4 levels were significantly higher in patients with LASEC than in the control group (p<0.05). Only PF 4 was higher in the AF group than in those with sinus rhythm (p<0.05). As to plasminogen activator and PAI-I levels, only tissue plasminogen activator levels were found to be higher in the AF group than in those with sinus rhythm and the control group (p<0.05). In patients with mitral stenosis and sinus rhythm, if LASEC is present, coagulation activation, platelet activation, and endothelial dysfunction are similar in patients with AF, and anticoagulation should be considered in these patients.

Does P-Wave Dispersion Predict the Atrial Fibrillation Occurrence After Direct-Current Shock Therapy?

Supraventricular tachycardia attacks, including atrial fibrillation (AF), occur after both external and internal cardioversions. These attacks of atrial fibrillation after direct-current (DC) shock may be related to hemodynamic impairment, thromboembolic events, or enhanced electrical instability of the ventricular and atrial myocardium, especially in predisposed patients. In this study, the authors aimed to show the importance of P-wave dispersion (PWD), which lead the atrium to fibrillate, in predicting post-DC shock AF after external cardioversion. Thus physicians may be able to choose the patients with high risk for AF occurrence and apply some other therapeutic modalities to those patients. The authors identified 18 patients in whom an AF attack was induced by urgent or elective cardioversion for a ventricular tachycardia attack and compared these patients with a control group composed of 40 patients without AF in regard to some clinical, echocardiographic, and electrocardiographic parameters. Left atrial diameters were greater (4.3 ±0.3 vs 3.5 ±0.5 cm, p=0.001), left ventricular ejection fractions (LVEF) were lower (45.2 ±8.2 vs 54.9 ±7.5, p=0.001), the energy needed for successful cardioversion was higher (166.6 ±59.4 vs 80.8 ±51.6 J, p=0.001), and P max (135.2 ±7.4 vs 118.7 ±10.5 ms, p=0.001) and PWD (53.8 ±12.2 vs 23.8 ±9.5 ms, p=0.001) values were higher in patients with AF when compared to those without AF. Thus, the patients with higher PWD values had a greater risk for development of AF after a DC shock.

Do Different Atrial Flutter Types Carry the Same Thromboembolic Risk?

Thromboembolic risk of atrial flutter (AFl) types has not been elucidated sufficiently in previous reports. The authors classified the patients according to surface electrocardiogram and electrophysiologic characteristics as those with typical AFl (37 patients, 78.4% male, mean age 59.8 ±9.5 years) and atypical AFl (13 patients, 69.2% male, mean age 60.9 ±6.9 years) and compared them regarding some clinical, echocardiographic, and hematologic parameters. An age- and gender-matched control group composed of 20 individuals without any organic heart disease in sinus rhythm was chosen (80% male, mean age 60.3 ±7.9 years). Clinical features such as age, gender, organic heart disease, hypertension, diabetes mellitus, AFl duration, and the prevalence of paroxysmal atrial fibrillation were similar in both AFl groups. Echocardiographic parameters such as left ventricular ejection fraction, left atrial (LA) diameter, LA spontaneous echo contrast, and LA appendage emptying velocities were similar in both AFl groups. Fibrinogen, fibrin D-dimer, and thrombin-antithrombin III levels reflecting coagulation system activity were found to be increased in the patients with atypical AFl when compared with those with typical AFl and the control group (p<0.001). In Pearson’s correlation analysis, significant correlation between these hematologic markers and clinical and echocardiographic parameters were not found (p>0.05). The coagulation system activity was found to be increased in patients with atypical AFl. Thus, anticoagulation due to the increased thromboembolic risk should be considered in patients with atypical AFl.

Hyperthyroidism and Complete Atrioventricular Block

Although cardiovascular manifestations in thyroid disorders are frequently encountered in clinical practice, atrioventricular (AV) conduction disorders, especially in hyperthyroidism, are rare. There are some proposed mechanisms for AV blocks in hyperthyroidism but the exact mechanism is still unknown. The authors report 2 cases with thyroid function disorders and complete AV block, and the electrophysiologic characteristics of these 2 patients, and they review and speculate on similar reported cases.

Relationship Between Plaque Morphology of Carotid Artery and Aortic Valve Calcification

Aortic and mitral valvular calcifications are found to be associated with atherosclerotic risk factors and are largely accepted as part of a generalized atherosclerotic process. As well as the severity of stenosis, embologenic properties of plaques are also responsible for ischemic poten tials of atherosclerotic plaques in carotid arteries. In this study, the authors aimed to define the characteristics of plaque morphology in patients with and without aortic valvular calcification (AVC) and to show the association between AVC and carotid plaque characteristics. Carotid plaque morphology in 182 consecutive patients with AVC was compared with plaque charac teristics in 170 patients without AVC. Risk factors for atherosclerosis, age, and gender were similar in patients with and without AVC. The presence of carotid atherosclerosis, complex atheromas, and carotid artery stenosis was significantly higher in patients with AVC when compared with those without AVC (p < 0.001, p < 0.001, and p < 0.05, respectively). Unstable plaques (Types I and II) were also found to be more common in the patients with AVC than in those without AVC (p < 0.001). This study demonstrated the strong correlation between AVC and carotid atheromas. The plaques in patients with AVC are more unstable in morphology than in those without AVC, and this may explain the higher stroke incidence in these patients.

Seroprevalence of hepatitis B and C in subjects admitted to a cardiology clinics in Turkey

A seroepidemiological study was conducted to assess the seroprevalence of hepatitis B surface antigen (HBs Ag) and antibodies to hepatitis C virus (Anti-HCV) in 14,196 patients hospitalized in our cardiology clinics. Threehundred and fifty five (355) patients (2.43%) were found to be positive for HBs Ag, a hundred and sixty six (166) patients (1.09%) were positive for Anti-HCV and ten patients (0.07%) were positive for both. The presence of HBs Ag and Anti-HCV was similar in patients living in rural and urban areas. The presence of risk factors was greater in the patients with Anti-HCV. The prevalences of HBs Ag and Anti-HCV were found to be comparable with those reported in other mediterranean countries in Europe.

Evaluation of malnutrition detected with the Nutritional Risk Screening 2002 (NRS-2002) and the quality of life in hospitalized patients with chronic obstructive pulmonary disease

BACKGROUND

Patients with severe chronic obstructive pulmonary disease (COPD) have impaired quality of life, but the relationship between their nutritional status and quality of life has not been established. The aim of this study was to determine the relationship between quality of life and nutritional status in hospitalized COPD patients.

METHODS

Demographic data, quality of life and nutritional status of 90 inpatients with a mean age of 68.76 ± 10.85 years were enrolled in the study. The Nutritional Risk Screening 2002 (NRS-2002) tool was used to evaluate their nutritional status. The quality of life was assessed using the Short Form-36 (SF-36) questionnaire. The correlation analysis was used for the relationship between SF-36 subscales and nutritional status variables.

RESULTS

Of the 90 COPD patients included in the study, 54.4 % were men, and 45.6 % were women. Moderate, severe, and very severe COPD were detected in 37.8 %, 38.9 %, and 23.3 % of the patients, respectively. At risk of malnutrition were 55.6 % of the 90 COPD patients, whereas 44.4 % were not. The scores for physical function, physical role functioning, pain, general health, emotional role functioning, vitality, social function, and mental function subscales were lower in the patients at risk of malnutrition (p <0.001). There was a statistically significant negative correlation between malnutrition score and the subscores of SF-36 related to physical function, physical role functioning, pain, general health, emotional role functioning, vitality, social function, and mental function (p <0.001).

CONCLUSIONS

COPD patients were found to have a high risk of malnutrition that adversely affects their quality of life. Therefore, the evaluation of the nutritional status of COPD patients should be an integral part of their clinical treatment plans aiming towards improving their quality of life. Hippokratia 2016, 20(2):147-152.

Glucocorticoid sensitivity in Behçet's disease

OBJECTIVE

Glucocorticoid (GC) sensitivity is highly variable among individuals and has been associated with susceptibility to develop (auto-)inflammatory disorders. The purpose of the study was to assess GC sensitivity in Behçet's disease (BD) by studying the distribution of four GC receptor (GR) gene polymorphisms and by measuring in vitro cellular GC sensitivity.

METHODS

Healthy controls and patients with BD in three independent cohorts were genotyped for four functional GR gene polymorphisms. To gain insight into functional differences in in vitro GC sensitivity, 19 patients with BD were studied using two bioassays and a whole-cell dexamethasone-binding assay. Finally, mRNA expression levels of GR splice variants (GR-α and GR-β) were measured.

RESULTS

Healthy controls and BD patients in the three separate cohorts had similar distributions of the four GR polymorphisms. The Bcll and 9β minor alleles frequency differed significantly between Caucasians and Mideast and Turkish individuals. At the functional level, a decreased in vitro cellular GC sensitivity was observed. GR number in peripheral blood mononuclear cells was higher in BD compared with controls. The ratio of GR-α/GR-β mRNA expression levels was significantly lower in BD.

CONCLUSIONS

Polymorphisms in the GR gene are not associated with susceptibility to BD. However, in vitro cellular GC sensitivity is decreased in BD, possibly mediated by a relative higher expression of the dominant negative GR-β splice variant. This decreased in vitro GC sensitivity might play an as yet unidentified role in the pathophysiology of BD.

QT dispersion significantly increases after implantable cardioverter-defibrillator shocks

OBJECTIVE

To determine whether QT dispersion (QTd), a noninvasive electrocardiographic parameter of ventricular tachyarrhythmia risk assessment, is changed by implantable cardioverter-defibrillator (ICD) shocks delivered during implantation process, to analyze the duration of these changes, and to further evaluate the effect of amiodarone on these parameters.

METHODS

Twenty-six consecutive patients who are scheduled to undergo ICD implantation for aborted sudden cardiac death or documented symptomatic sustained ventricular tachycardia were enrolled into the study. A simultaneous 12-lead electrocardiogram (ECG) was recorded after the ICD implantation just before starting the testing shock when the patients were under general anesthesia (baseline record) and at 1st, 5th, 10th, 15th, 20th, 25th, and 30th minutes after the successful shocks. RR interval, QT interval, corrected QT interval (QTc), QTd, and corrected QTd (QTcd) were all measured and calculated on ECG.

RESULTS

At 1st minute after the successful shock, an abrupt increase (from 67.0 +/- 13.8 ms to 94.8+/-21 ms, P < 0.0001) was observed in QTcd, which was followed by a gradual return to the preshock values at 20th minute. Analysis of patients with and without long-term oral amiodarone treatment showed that in amiodarone-pretreated patients QTcd returned to the baseline value earlier than in patients without amiodarone treatment (15 minutes vs 20 minutes, respectively).

CONCLUSIONS

ICD shocks cause an increase in QTcd lasting for up to 20th minute, which may predominate in some important clinical problems like electrical storm. Amiodarone, with the desirable effect on QTcd, may reduce the proarrhythmic effects of ICD shocks.

P-wave durations in patients experiencing atrial fibrillation during exercise testing

Augmented sympathoadrenal activity during exercise may contribute to occurrence of various arrhythmias including atrial fibrillation (AF). The prolongation of intraatrial and interatrial conduction times and inhomogeneous propagation of sinus impulses are well-known characteristics of the atrium prone to fibrillate and are evaluated by maximum P-wave duration (P max), P-wave dispersion (PWD). To show the increased P max and PWD values in patients experiencing AF during exercise testing and the role of beta blockade on treatment of exercise-induced AF, 22 of these patients were compared with a control group consisting of 41 patients without AF attacks. P max (p = 0.001) and PWD (p = 0.001) values were significantly higher in patients with AF compared to those without AF. The development of AF during exercise testing was found to be positively correlated with P max (r = 0.87, p < 0.001), PWD (r = 0.83, p = 0.001), and work load (r = 0.34, p = 0.002) and negatively correlated with ejection fraction (r = -0.26, p=0.02). After the treatment with beta-blocking agents for 2 weeks, the decrease in P max and PWD values was accompanied by a much lower prevalence of exercise-induced AF. Consequently, the patients with AF had greater P max and PWD values compared to control subjects, and these simple parameters were well correlated with the occurrence of AF during exercise testing. Furthermore, treatment of these patients with beta blockers would appear to decrease the recurrence of exercise-induced AF and to be associated with a decrease in P-wave durations.

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 (DeltaLF/HF1) and the change in the number of ventricular extrasystole (DeltaVES). The decrease in LF/HF1 > or = 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 > or = 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.

Determination of vitreous interleukin-1 (IL-1) and tumour necrosis factor (TNF) levels in proliferative diabetic retinopathy

We measured interleukin-1 beta (IL-1beta) and tumour necrosis factor-alpha (TNF-alpha) in the vitreous humour and serum of patients with proliferative diabetic retinopathy (PDR), in order to determine the role of these cytokines in the pathogenesis of the disease. Vitreous and serum samples were collected from 21 patients with PDR who were undergoing pars plana vitrectomy. Control vitreous samples were obtained from cadavers and control serum samples from healthy subjects. The cytokines were measured by enzyme-linked immunosorbent assay. Vitreous IL-1beta and TNF-alpha concentrations in patients with PDR exceeded those of controls (P<0.05), as did serum IL-1beta and TNF-alpha. We suggest that increased vitreous IL-1beta and TNF-alpha levels may play a significant role in the pathogenesis of PDR, which features abnormal cell proliferation and neovascularisation.

Evaluation of serum levels of solubilized adhesion molecules in patients with aortocoronary saphenous vein grafts

OBJECTIVE

To assess the diagnostic importance of serum-solubilized adhesion molecules, vascular cell adhesion molecule-1, intercellular adhesion molecule-1, sE-selectin and sP-selectin in aortocoronary saphenous vein graft disease.

METHODS

The study population was composed of two groups consisting of 41 patients with saphenous vein graft stenosis (stenosis group) and 43 patients without saphenous vein graft stenosis (no-stenosis group) based on the results of coronary angiography. All patients underwent coronary artery bypass graft operation involving the use of at least one saphenous vein graft for bypass. At the time of cardiac catheterization, it had been more than 1 year since the operation.

RESULTS

Serum level of sP-selectin was significantly higher in the stenosis group than in the no-stenosis group (72.9+/-21.7 versus 48.7+/-18.6 ng/ml, P<0.001). No differences were found between the two groups with respect to serum levels of sE-selectin, intercellular adhesion molecule-1 and vascular cell adhesion molecule-1. Multivariate analysis revealed that only serum levels of sP-selectin, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol were independently correlated with the stenosis of saphenous vein grafts. A cutoff value of serum sP-selectin >57.5 ng/ml yields a specificity of 79.5%, a sensitivity of 73.3% and a positive predictive value of 80.5% for saphenous vein graft stenosis.

CONCLUSION

In this study, sP-selectin level was found to be significantly higher in the group that had late aortocoronary saphenous vein bypass graft disease. This result suggests that platelet activation may play a causal role in late graft disease.

Collaterals that regressed after angioplasty can be recruited to protect the left ventricle in case of an acute occlusion

A considerable fraction of collaterals has been shown to regress immediately after percutaneous transluminal coronary angioplasty (PTCA), but the fate of these well-developed collaterals is unknown. The authors aimed to show the protective role of these recruitable collaterals in case of an acute myocardial infarction (MI). They identified 22 patients who underwent PTCA and then were rehospitalized owing to acute myocardial infarction. These patients were compared with a group consisting of 48 patients hospitalized owing to acute MI without a history of previous PTCA. Then, the patients with collaterals were compared with the patients without collaterals to define the factors affecting the collateral formation. All the patients with collaterals before PTCA were shown to have collaterals also after AMI, and collateral grades were greater after MI (1.67 +/-0.98) when compared with those before PTCA (0.73 +/-0.7) (p = 0.001). Coronary collaterals were more commonly seen in patients with a history of previous PTCA (p = 0.005), and the grades of collaterals were also higher in these patients when compared with those without PTCA. Left ventricle score indices were lower and left ventricular ejection fractions (LVEF) were higher in patients with a history of PTCA (p = 0.001). Logistic regression analysis revealed that smoking increased the development of collaterals after AMI 3.8 fold, aspirin use 4.1 fold. On the contrary, diabetes mellitus (DM) decreased this 6.67 fold. As a result, well-developed coronary collaterals are preserved even if they have regressed after restoration of flow, and they may become functional and protect the myocardium against acute ischemia.

Improvement in sympatho-vagal imbalance and heart rate variability in patients with mitral stenosis after percutaneous balloon commissurotomy

Elevated sympathetic nerve activity in patients with mitral stenosis (MS) may be an index of the severity of the disease. Percutaneous mitral balloon commissurotomy (PMBC) is now a standard treatment for many patients with symptomatic MS. We aimed to show the effects of PMBC on autonomic nervous system activity in the patients with MS by heart rate variability (HRV) analysis. Fifty-four consecutive patients with mitral stenosis and sinus rhythm who underwent percutaneous mitral commissurotomy were enrolled. Apart from significant haemodynamic improvements, mean heart rate (HR), LF day, LF night, LF/HF day and night significantly decreased and SDNN, RMSSD, PNN50, HF day and night significantly increased in the early period after PMBC and these changes were preserved for up to one month. SDNN was positively correlated with left ventricle ejection fraction (LVEF) but negatively correlated with mean valve area (MVA), left atrial (LA) diameter and pressure, right atrial (RA) pressure; LF/HF day ratio was positively correlated with LA diameter and pressure, mean transmitral gradient and negatively correlated with LVEF; LF/HF night ratio was positively correlated with LA pressure and mean transmitral gradient. The increase in SDNN was correlated with the change in LA and RA pressure. The decrease in LF/HF ratio after PMBC was significantly correlated with the changes in the mean transmitral gradient, LA pressure and RA pressure. As a result, the heart rate variability and autonomic nervous system function in patients with mitral stenosis are correlated with the atrial pressures and left ventricular function. These parameters significantly change in the early period after PMBC and are preserved at one month. The improvement in the heart rate variability and sympatho-vagal balance are significantly affected by the early changes in atrial pressures after PMBC.

Sympathetic overactivity in patients with rheumatic mitral stenosis

BACKGROUND

Mitral stenosis may increase sympathetic nervous activity by increasing left atrial pressure and reducing cardiac output. And elevated sympathetic nerve activity may be a risk factor for the development of clinical manifestations of mitral stenosis. In this study, we assessed the autonomic nervous system activity in patients with mitral stenosis by heart rate variability analysis and defined factors affecting autonomic functions.

METHODS AND RESULTS

Fifty-four patients with rheumatic mitral stenosis were compared with an age- and gender-matched control group composed of 42 healthy individuals. SDNN, RMSSD, PNN50, and HF were lower; mean heart rate (HR), LF and LF/HF ratio were higher in the patients with mitral stenosis compared to the control group. SDNN was correlated positively with left ventricle ejection fraction (LVEF), negatively with mitral valve area, left atrial (LA) diameter, and duration of symptoms. RMSSD was correlated positively with mean transmitral gradient, negatively correlated with age; PNN50 was correlated negatively with mitral valve area and positively correlated with transmitral gradient. LF was positively and HF was negatively correlated with LA diameter; LF was correlated positively, and HF was negatively correlated with duration of symptoms. LF/HF ratio was positively correlated with LA diameter and duration of symptoms, negatively with LVEF and mean valve area.

CONCLUSION

As a result, sympathetic nervous system activity is increased in patients with mitral stenosis and sympathetic overactivity worsens their symptoms. Most significant factors that affect autonomic functions in these patients are left atrial dilatation and mitral valve area.

Effects of previously well-developed collateral vessels on left internal mammary artery graft flow after bypass surgery

Transthoracic Doppler ultrasonography can assess left internal mammary artery patency and flow after coronary artery bypass grafting. We aimed to show, by transthoracic Doppler ultrasonography, the early effects upon left internal mammary artery graft flow of preoperative collateral vessels supplying the left anterior descending artery. Thirty-four consecutive patients undergoing coronary artery bypass were prospectively enrolled: 19 patients with collateral vessels supplying the left anterior descending were compared with 15 patients without collaterals. After bypass, end-diastolic velocity, mean velocity, flow volume, and ejection fraction were significantly greater, and the resistivity index was lower in patients with collateral vessels. The changes in velocities, volume, resistivity index, and pulsatility index were also found to be greater in patients with collateral vessels than in those without collaterals. Collateral vessels were the only factor affecting the changes in end-diastolic volume, mean velocity, flow volume, and resistivity index in multivariate analysis. Three factors affected postoperative left ventricular ejection fraction: collateral vessels, preoperative ejection fraction, and changes in left internal mammary flow volume. We conclude that patients with well-developed collaterals to the left anterior descending have better flow in the left internal mammary graft and more significant improvement in left ventricular function after coronary bypass. The flow volume of the mammary graft and the improvement of ventricular systolic functions after coronary bypass might be presumed with the presence of grade 2 or 3 preoperative collateral vessels.

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.

Do collaterals affect heart rate variability in patients with acute myocardial infarction?

BACKGROUND

The protective effects and the prognostic importance of collaterals during and after acute myocardial infarction (MI) are under debate and heart rate variability (HRV) is a strong predictor of risk of mortality and arrhythmic events after acute MI. We aimed to examine the effects of collateral circulation on HRV in the early period after acute MI.

METHODS

Sixty-four patients admitted to our clinics who were diagnosed with acute anterior MI and underwent thrombolytic therapy were enrolled in this study. We applied 24 h Holter monitoring for HRV analysis to all patients and compared the patients with and without collaterals to the infarct-related artery.

RESULTS

Mean heart rate, low frequency (LF) (day, night and 24 h) and LF/high frequency (HF) (day, night and 24 h) were higher, SD of all NN intervals (SDNN), root mean square of successive differences (RMSSD), number of NN intervals that differed by more than 50 ms from the adjacent interval divided by the total number of all NN intervals (PNN50) and HF night values were lower in patients without collaterals than in those with collaterals. SDNN was negatively correlated with left anterior descending coronary artery (LAD) stenosis, ventricle score indices and left ventricular ejection fraction (LVEF); LF/HF ratio was positively correlated with ventricle score indices and negatively correlated with LVEF and Thrombolysis in Myocardial Infarction flow grade. Linear regression analysis showed that ventricle score index and coronary collaterals affect HRV and LAD stenosis, ventricle score, LVEF and coronary collaterals affect LF/HF ratio. A SDNN <80 ms increased the development of ventricular arrhythmias in the early period by 4.7 fold, a LF/HF ratio >2.7 increased it by 9.8 fold and a LVEF <35% increased it by 12.8 fold, whereas the presence of well-developed collaterals decreased the arrhythmia development by 2.5 fold.

CONCLUSIONS

The collaterals to the infarct-related artery have great impact on HRV, autonomic nervous system activity and the development of ventricular arrhythmias in patients with acute anterior MI. Our results suggest a protective role of collaterals on myocardial electrophysiology in the early period after acute MI.

Increased P wave dispersion after the radiofrequency catheter ablation in overt pre-excitation patients: the role of atrial vulnerability

The pathogenesis of paroxysmal atrial fibrillation (PAF) in patients with overt pre-excitation and effect of elimination of accessory pathways on the appearance of AF are still controversial. We demonstrated the increased P max and P wave dispersion (PWD) reflecting more inhomogeneous and prolonged atrial conduction in patients with Wolff-Parkinson-White (WPW) syndrome and PAF attacks. One-hundred and fifty-one patients who underwent radiofrequency (RF) catheter ablation due to paroxysmal tachycardia medicated by accessory pathway were enrolled in this study. The patients were classified into two groups according to the presence of previous PAF attacks. We compared the clinical characteristics, echocardiograhic findings, P max and PWD values measured after normalization of PR intervals and disappearance of pre-excitation after ablation in overt pre-excitation patients. Although the differences in age, left atrial diameter and left ventricular ejection fraction (LVEF) were not significant in both groups, P maximum (130.0+/-8.4 vs. 122.3+/-8.7 ms, p=0.002) and P wave dispersion values measured after ablation (50.3+/-7.2 vs. 35.7+/-6.1 ms, p=0.001) were significantly higher in patients with previous PAF attacks. Accessory pathway (AP) antegrade and retrograde effective refractory period (ERP) values were shorter (276+/-27.3 vs. 321.0+/-48.7, p=0.001; 263.4+/-41.3 vs. 299.7+/-38.2, p=0.002, respectively) in patients with PAF attack when compared to those without PAF attacks. Higher P wave dispersion values in patients with previous PAF attacks suggest the important role of inhomogenous and discontinuous propagation of sinus impulses. Therefore, we concluded that not only the accessory pathway but also inhomogenous propagation of sinus impulses may play an important role in occurrence of AF in patients with pre-excitation.

Does claudication affect the development of coronary collaterals?

Atherothrombosis is a generalized disease process that affects large- and medium-diameter arteries throughout the arterial tree. In this study, we aimed to evaluate the correlation between collaterals in different vascular beds. Patients who had undergone digital subtraction angiography for symptomatic lower extremity peripheral arterial disease and coronary angiography after an acute anterior myocardial infarction (MI) were compared with a control group composed of those patients who were hospitalized for acute anterior MI and underwent coronary angiography but had no claudication and had an ankle-brachial index of greater than 0.9 in both legs. In claudicants, stenosis in the left anterior descending artery (LAD) (90.3 +/- 17.5 vs 78.6 +/- 13.8, P = 0.005) was greater compared with the patients without claudication. The collaterals to the LAD (88% vs 37.5%, P = 0.001) and the collateral grades (1.7 +/- 0.7 vs 0.7 +/- 0.9, P = 0.001) were higher in the patients with claudication compared with those without claudication. A previous history of angina (52.2% vs 16.3%, P = 0.001), claudication (39.1% vs 4.6%, P = 0.001), and peripheral collaterals (45.7% vs 6.9%, P = 0.001) were higher in the patients with coronary collaterals than in those without. The factors affecting the development of coronary collaterals were claudication [relative risk (RR): 8.8; 95% confidence interval (CI): 2.1-39.8], peripheral collaterals (RR: 1.1; 95% CI: 1.1-1.3), and LAD stenosis (RR: 1.2; 95% CI: 0.03-29.1). Our results suggest that the presence of collateralization or angiogenesis in one vascular bed highly predicts collateralization in another arterial bed.

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.

[Evaluation of early hemodynamic changes in the carotid arteries after permanent pacemaker implantation with color Doppler US]

PURPOSE

Both carotid arteries of the patients were examined with color Doppler ultrasonography before and after the placement of a permanent pacemaker, and the results were discussed.

MATERIALS AND METHODS

Twelve patients with pacemaker indication aged between 19-81 years were included in the study. The day before and after pacemaker implantation, maximum systolic velocity, end diastolic velocity, mean velocity, resistivity index and pulsatility index of the bilateral carotid arteries were measured. Area measuring and flow volume were calculated by using the transverse imaging of the same points of carotid arteries. Statistical analysis of the data was made with paired samples t-test.

RESULTS

Heart rates of the patients were statistically higher before pacemaker implantation (p<0.001). Maximum systolic velocity of bilateral common carotid arteries, left internal carotid artery and right internal carotid artery decreased significantly after pacemaker implantation (respectively p<0.01, p<0.01, and p<0.05). We also found prominent decrease in maximum systolic velocity of both external carotid arteries after pacemaker implantation (p<0.05). End diastolic velocity, mean velocity, area and the flow volume of the carotid arteries did not change markedly. Resistivity and pulsatility index values of bilateral common and internal carotid arteries decreased significantly after pacemaker implantation (p<0.05).

CONCLUSION

Decrease in maximum systolic velocity of the carotid arteries after pacemaker implantation may be due to the possible reduction in cardiac output or the treatment of bradycardia. However, flow volumes of the carotid arteries did not change after pacemaker and we concluded that the early neurological dysfunction would not be associated with the functional failure of the carotid arteries.

Association between mean platelet volume and autonomic nervous system functions: Increased mean platelet volume reflects sympathetic overactivity

BACKGROUND

Increased mean platelet volume (MPV) may reflect increased platelet activation or increased numbers of large, hyperaggregable platelets, and is accepted as an independent coronary risk factor. The adrenergic system has effects on platelet activation and thrombocytopoiesis.

OBJECTIVE

To assess the effects of autonomic nervous system activity on MPV in patients with acute myocardial infarction (MI).

METHODS AND RESULTS

Forty-seven patients with acute anterior MI were compared with 32 patients with healthy coronary arteries. All patients underwent heart rate (HR) variability analysis using 24 h Holter monitoring. Blood samples were taken for MPV measurements twice a day (day- and nighttime) during Holter monitoring. Mean HR, low frequency band of HR variability power spectrum to high frequency band of HR variability power spectrum (LF:HF) ratio, LF and MPV were higher in patients with anterior MI than in the control group. SD of all NN (RR) intervals, root mean square of successive differences, number of NN intervals that differed by more than 50 ms from the adjacent interval divided by the total number of all NN intervals, HF bands and platelet counts were lower in the patients with anterior MI than in the control group. Daytime LF bands, LF:HF ratio and MPV were significantly higher, and HF bands were significantly lower than the nighttime values for both groups. The differences in daytime and nighttime measurements were more significant in the patients with acute MI than in the control group. Pearson's correlation analysis showed that MPV was positively correlated with ventricle score, degree of left anterior descending artery stenosis, mean HR, LF bands and LF:HF ratio; and negatively correlated with the SD of all NN intervals, HF bands and platelet count. Multivariate analysis revealed that MPV was significantly affected by ventricle score and the LF:HF ratio.

CONCLUSIONS

MPV was significantly higher in the patients with acute MI. In both groups, MPV showed great daytime and nighttime variation, which can be attributed to alterations in the autonomic nervous system. The authors suggest that the prognostic role of increased MPV in patients with acute MI is closely associated with increased sympathetic activity and decreased HR variability.

[Classification of patients with complete atrioventricular block according to etiological, demographic and clinical features and pacemaker needs]

OBJECTIVE

Complete atrioventricular (AV) block is a rhythm disorder that can result from various causes. The aim of this study was to define etiological factors, clinical features, pacemaker needs, in-hospital mortality rates and factors affecting these parameters in the patients with complete AV block.

METHODS

For this aim, 191 consecutive patients admitted to the hospital with complete AV block or who developed AV block during their hospital course between January 1999-September 2002 were included into the study.

RESULTS

The most common underlying cause of AV block was found to be the ischemia, which was followed by unknown etiology and iatrogenic complete AV block. The most common cause of in-hospital mortality was ischemic (especially acute) heart disease. No etiological factor for complete AV block was found in most of symptomatic patients presented with syncope. In patients with ischemic complete AV block, mortality and syncope rates were found to be high, especially in patients with multivessel disease. Permanent pacemaker was implanted in 76 of 191 patients with complete AV block and the significant portion of these patients were those without an etiological cause.

CONCLUSION

Thus, it is revealed that factors affecting mortality in patients with complete AV block are acute myocardial infarction and age while other clinical parameters and pacemaker implantation had no effects on mortality.

Differential diagnosis and clinical course of amiodarone-induced thyroid dysfunction

BACKGROUND

Amiodarone is an iodine-rich drug widely used for the management of various arrhythmias, but its clinical utility is usually limited by the high frequency of numerous side effects, most frequently disturbance of thyroid function.

MATERIAL/METHODS

The present study presents the laboratory tests, color flow Doppler sonography (CFDS) findings, treatment and prognosis of 22 patients with amiodarone-induced thyroid dysfunction.

RESULTS

Eleven patients developed amiodarone- induced thyrotoxicosis (AIT), ten developed amiodarone-induced hypothyroidism (AIH) and one patient first developed AIT, followed by AIH. Age, amiodarone doses, duration of amiodarone treatment and discontinuation of amiodarone were similar in the patients with AIT and AIH. AIT was found more commonly in male patients, AIH in female patients. Color flow Doppler sonographic examination was performed in all patients with AIT to differentiate type 1 and 2 AIT. In ten patients, CFDS demonstrated increased glandular vascularity, diagnostic for type 1 AIT.

CONCLUSIONS

This paper presents patients with AIT treated successfully with propylthiouracil or prednisolone after developing thyroid dysfunction as a consequence of amiodarone use. The role of thyroid Doppler in managing these patients is emphasized.

Pars plana vitrectomy in ocular Behçet's disease

PURPOSE

To evaluate the results of pars plana vitrectomy in Behçet patients with dense vitreous opacities, and its effect on intraocular inflammatory episodes and visual prognosis.

METHODS

The study group consisted of nine patients (one eye in eight patients, both eyes in one) with Behçet's disease who underwent pars plana vitrectomy because of dense vitreous opacification. The indications for vitrectomy, the effect of vitrectomy on the frequency of severe intraocular inflammatory episodes, and visual prognosis were investigated in these patients. All the patients were male, and their ages ranged between 28-45 years. Combined lensectomy was performed on those with complicated cataracts. The postoperative follow-up was between 12-66 months.

RESULTS

In all of the patients preoperative visual acuity was hand motions. Postoperatively there was no change in vision in five eyes, however visual acuity improved in five eyes, between counting fingers and 0.4. None of the patients showed any severe postoperative intraocular inflammatory episodes, and phthisis did not develop in any of the patients.

CONCLUSION

In this study, pars plana vitrectomy was found to have a beneficial effect on the prognosis of vision. There was also a decrease in the frequency of severe intraocular inflammatory episodes in patients with Behçet's disease with severe vitreous opacities, who did not respond to maximum medical treatment. However, further studies on larger groups should be performed in order to confirm the findings of this study.

Determinants of persistent atrial fibrillation in patients with DDD pacemaker implantation

Occurrence of AF in a pacemaker implanted patient is a significant cause of morbidity and mortality. The aim of this study was to prospectively investigate the clinical, echocardiographic, and electrocardiographic determinants of persistent AF in patients with DDD pacemakers. A 101 consecutive patients were followed for an average of 19.8 +/- 11.8 months. Persistent AF was documented in 21 (20.8%) patients and 80 (79.2%) patients were in sinus or physiologically paced rhythm. In patients with persistent AF, previous AF attacks were observed more frequently (P < 0.03) and left atrial dimension was higher (3.5 +/- 0.6 vs 3.0 +/- 0.5 cm, P < 0.001). Average P maximum and P wave dispersion (PWD) values calculated in a 12-lead surface electrocardiogram were also found to be significantly higher in patients with persistent AF (P < 0.001). Cox regression analysis demonstrated that the presence of previous AF attacks (RR 8.95, P < 0.001), increased left atrial dimension (RR 2.1, P < 0.02), P maximum duration 120 ms (RR 6.1, P < 0.001), and PWD 40 ms (RR 12.2, P < 0.001) were associated with an increased risk of persistent AF. Cut-off points were 120 ms for P maximum and 40 ms for PWD. Sensitivity, specificity, and positive and negative predictive values were calculated as 76.2, 82.5, 53.3, and 92.9 for P maximum and as 85.7, 87.5, 64.3, and 95.9 for PWD, respectively. In patients with DDD pacemakers, previous AF attacks, increased left atrial dimension, P maximum value of 120 ms, and a PWD value of 40 ms were associated with a significantly increased risk of persistent AF. These patients must further be managed with other treatment modalities to prevent the development of persistent AF.

Increased sympathetic nervous system activity as cause of exercise-induced ventricular tachycardia in patients with normal coronary arteries

In this prospective study, we set out to determine whether analysis of heart rate variability (HRV) in patients with exercise-induced ventricular tachycardia (EIVT) and normal coronary arteries would reveal increased sympathetic nervous system activity. From January 1996 to December 2001, we compared 16 patients with EIVT and normal coronary arteries with an age- and sex-matched control group. Analysis of HRV showed that parameters indicative of parasympathetic activity were lower in our study group than in our control group: standard deviation of the mean of qualified NN intervals (SDNN), 81.6 +/- 14.5 vs 139.3 +/- 11.0, P <0.001; root mean square of successive differences (RMSSD), 22.3 +/- 4.8 vs 36.3 +/- 6.6, P <0.001; number of NN intervals that differed by more than 5 ms from the adjacent interval, divided by the total number of NN intervals (PNN50), 4.8 +/- 1.5 vs 10.2 +/- 3. 1, P <0.001; and high-frequency component (HF), 28.7 +/- 2.5 vs 32.4 +/- 3.9, P <0.05. Conversely, parameters indicative of sympathetic activity were higher in patients with EIVT: low-frequency component (LF), 71.2 +/- 5.0 vs 52.0 +/- 5.8, P <0.001; and absolute low/high frequency component ratio (LF/HF), 2.7 +/- 0.2 vs 1.6 +/- 0.2, P <0.001. There was a positive correlation between EIVT and LF (r=0.79, P <0.001) and between EIVT and LF/HF (r=0.81, P <0.001). Our results suggest the presence of increased sympathetic and decreased parasympathetic tone in patients with EIVT. We conclude that EIVT is associated with an imbalance in the autonomic nervous system.

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.

Coronary artery anomalies in adult patients

BACKGROUND

Coronary artery anomalies are discovered in less than 1% of angiography series. Since the number of angiographies and coronary bypass operations are increasing significantly every day, these anomalies are of clinical importance.

MATERIAL/METHODS

58,023 coronary angiographies were performed in the cardiology clinic of our hospital from 1978 to 2001. Coronary artery anomalies were discovered in 257 of these cases (0.44%). The mean age of these patients was 51.9+/-11.4 years (18-82). 80% were male (n=207).

RESULTS

The circumflex artery (CXA) was the most frequently involved vessel (51.1%). Coronary arteries originating from the pulmonary artery were not encountered in our series due to the natural history of the disease. In 54 patients with coronary artery fistulae, 18 (33.3%) were closed by operation. Perioperative mortality was 5.5%. Acquired coronary artery fistulae or aneurysms due to trauma or inflammatory diseases are completely different entities and beyond the scope of this article. In 76 patients, open heart surgery was required for additional lesions, 57 of which were coronary artery bypass grafts.

CONCLUSIONS

Being usually asymptomatic, coronary artery anomalies are usually discovered incidentally in the adult population. These pathologies are important for practical purposes, especially for interventional cardiologists, radiologists and cardiac surgeons, who should be aware of these anatomical entities. LMCA originating from the right coronary system has been reported to result in sudden death and myocardial ischemia, so these mostly asymptomatic patients must be followed closely.

Effects of atrial pacing on QT dispersion in patients with coronary artery disease without angina pectoris and ST segment depression

The aim of this study was to investigate QT dispersion during atrial pacing in patients with coronary artery disease (CAD) without clinical ischemia, such as angina pectoris and ST segment depression. Thirteen patients with normal coronary arteries and 42 patients with CAD (12 with single-vessel, 16 with two-vessel and 14 with three-vessel disease) having no angina pectoris or ST segment depression during atrial pacing with maximum rate of 120/minute were enrolled in the study. Twelve-lead surface ECGs were recorded at 100 mm/second paper speed before pacing, at maximum pacing rate, and during the recovery period for measurement of QT interval parameters. Corrected QTd (QTcd) increased from 43.4 +/- 8.1 to 49.3 +/- 9.5 ms (p < 0.05) in the control group, from 46.1 +/- 8.1 to 74.3 +/- 7.7 ms (p < 0.0001) in the single-vessel disease group, from 48.5 +/- 10.4 to 93.8 +/- 22.1 ms in the two-vessel disease group (p < 0.0001), and from 49.7 +/- 13.6 to 128.5 +/- 31 ms (p < 0.0001) in the three-vessel disease group at peak atrial pacing period. A positive correlation was found between the severity of CAD and QTcd (r = 0.49, p < 0.0001). It was found that pacing-induced QTc dispersion identifies coronary disease extent, even when there is no ST depression or T wave inversion during pacing.