Swallowing-induced supraventricular arrhythmia: A different perspective to mechanism.

Atypical presentations of supraventricular arrhythmias constitute a diagnostic challenge which are not frequently reported in literature. Swallowing-induced supraventricular arrhythmia (SI-SVA), which was first described in 1926, is an intriguing presentation of supraventricular tachycardia and occurs during a wet or solid swallow. A 67-year-old man presented to our outpatient clinic complaining from recurrent episodes of sensation of palpitations and short duration pressure on his chest while swallowing since the last 2 weeks. Ambulatory rhythm Holter monitoring was suggestive of atrial fibrillation (AF) or atrial tachycardia attacks during swallowing. In addition, electrocardiography performed during solid food swallowing, showed short duration of AF consistent with the patient's symptoms. The patient was successfully treated with amiodarone. The main cause of SI-SVA is not known. Cross-talk of nerves during the impulse propagation might be the underlying cause of this phenomenon.

Plasminogen activator inhibitor-1 levels in patients with primary varicose vein.

AIM: Plasmin is involved in extracellular matrix remodeling by activating some matrix metallo-proteinases and degrading extracellular matrix; therefore component of fibrinolytic system such as tissue plasminogen activator and plasminogen activators inhibitors (PAI-1) might have a role in the pathogenesis of vascular remodeling. In our study we aimed to investigate the levels of PAI-1 levels in patients with primary varicose veins (VV) and in their age and gender matched control group. METHODS: Forty-one consecutive patients with peripheral varicose veins and 37 healthy age and gender-matched control subjects were included in the study from the outpatient cardiology and cardiovascular surgery clinic. Study population consisted of 41 consecutive patients who met the inclusion criteria and diagnosed as having class II primary VV according to CEAP classification. Routine biochemical and hematological analysis were performed in all patients and control subjects. RESULTS: Plasma levels of PAI-1 were found to be lower in patients than those in control subjects (5.19±2.2 ng/mL vs. 6.47±2.6 ng/mL, P=0.025). Logistic regression analysis revealed that only the plasma levels of PAI-1 were found to be independently but inversely associated with the presence of primary VVs (Odds ratio: 0.80 CI: 0.64-0.99, P=0.04). CONCLUSION: We have shown that PAI-1 levels are significantly decreased in patients with pVVs and it has an independent association with the presence of pVVs. However, its exact relation and role via matrix metlalloproteinases on the pathogenesis of the disease remains to be elucidated in further studies.

The role of allopurinol on oxidative stress in experimental hyperthyroidism.

AIM: During hyperthyroidism, production of free oxygen radicals derives, where xanthine oxidase may also play an important role. Allopurinol, a xanthine oxidase inhibitor, has a significant effect on thyrotoxicosis-related oxidative stress. However, the relationship between thyroid hormones, oxidative stress parameters and allopurinol remains to be explored. METHODS: Forty-two Wistar albino rats were divided into three groups. Rats in group A served as negative controls, while group B had untreated thyrotoxicosis and group C received allopurinol. Hyperthyroidism was induced by daily 0.2 mg/kg L-thyroxine intraperitoneally in groups B and C; 40 mg/kg allopurinol were given daily intraperitoneally. Efficacy of the treatment was assessed after 72 h and 21 days, by measuring serum xanthine oxidase (XO), malondialdehyde (MDA), glutathione (GSH), glutathione reductase (GR), glutathione peroxidase (GPx) and nitric oxide derivates (NO*x). RESULTS: In both time periods, serum XO, MDA, GSH and NO*x levels were significantly increased after thyroid hormone induction (p<0.05). Levels of XO, MDA and NO*x decreased with allopurinol treatment (p<0.05). There was a remarkable decrease in triiodothyronine levels in group C after 72 h (p<0.05), and in both triiodothyronine and thyroxine levels in group C after 21 days (p<0.05). There was no difference between groups B and C in means of serum GSH, GR and GPx levels (p>0.05). CONCLUSIONS: This study suggests an association between allopurinol and the biosynthesis of thyroid hormones. Allopurinol prevents the hyperthyroid state, which is mediated predominantly by triiodothyronine and not by XO. This issue has to be questioned in further studies where allopurinol is administered in control subjects.

Completion thyroidectomy for thyroid cancer.

BACKGROUND: Whether thyroid re-operations are associated with an increased complication risk is controversial. The aim of this study was to perform a retrospective analysis of patients undergoing re-operative surgery of the thyroid. We analyzed the safety and the impact of delay on complications before undertaking radicalization thyroidectomy. MATERIAL AND METHODS: From January 1996 to July 2002, 150 consecutive patients with thyroid cancer were treated in our institution. A total of 62 patients underwent completion thyroidectomy. Twenty-seven had undergone their initial operation in our centre. Medical and pathologic data were obtained retropectively. RESULTS: Pathological examination of the specimen after completion surgery revealed malignancy in a total of 35% of 62 patients. The time interval between initial surgery and completion thyroidectomy ranged from 5 days to 24 months (mean 3.1 months). Complications after re-operation were transient recurrent nerve injury in 1.6%, transient hypoparathyroidism in 4.8%, permanent hypoparathyroidism in 1.6% and chylous discharge in 1.6% of the patients. There was no significant difference between complication rates in patients operated on within 90 days or those operated on after this period (p > 0.05). CONCLUSIONS: This study suggests that completion thyroidectomy is safe in the hands of experienced endocrine surgeons and the timing of re-operation has no impact on the development of complications.

Diurnal variation of QT dispersion in patients with and without coronary artery disease.

QT dispersion defined as interlead QT variability in a 12-lead electrocardiogram was proposed by Day and associates as a simple method to evaluate the repolarization heterogenicity of the ventricular myocardium. The frequency of onset of myocardial infarction and sudden death has been reported to have a circadian variation, with a peak incidence in the early morning hours. The authors investigated whether there is diurnal variation of QT interval and QT interval dispersion in healthy subjects and in patients with coronary artery disease. The study population consisted of two groups. Group I consisted of 62 subjects without coronary artery disease and group II consisted of 82 patients with coronary artery disease. Twelve-lead ECG was recorded for each patient in the morning (between 7 AM and 8 AM), afternoon (between 3 PM and 5 PM) and at night (between 11 PM and 1 AM), on the day after performance of coronary angiography. QTc dispersion was significantly higher in patients with coronary artery disease than in healthy subjects in the morning hours and afternoon (p<0.001). Although the differences were much prominent in group I than group II, both QTc dispersion of morning and afternoon were significantly greater than those at night. There were no statistically significant differences between group I and group II at nighttime with respect to maximum QTc, minimum QTc intervals, and QTc dispersion (p>0.05). In conclusion, QT dispersion shows diurnal variation with an increase in the morning hours in both patients with coronary artery disease and subjects without coronary artery disease. The mechanism of diurnal variation of QT dispersion in patients with coronary artery disease is quite different from that of healthy subjects.

Increased levels of soluble adhesion molecules, E-selectin and P-selectin, in patients with infective endocarditis and embolic events.

AIMS: Inflammation-induced procoagulant changes and endothelial cell activation appear to play an important role in thromboembolic complications of infective endocarditis. Hence, the aim of this study was to compare the plasma levels of soluble adhesion molecules E- and P-selectin in infective endocarditis patients with and without embolic events, and healthy subjects. METHODS AND RESULTS: The study group consisted of 76 consecutive patients (mean age=26 years old, range from 8 to 64 years) with definite infective endocarditis according to the Duke criteria. Thirteen of the patients (17.1%) had embolic events. Transoesophageal echocardiographic examinations were performed on all patients within 3 days of initiation of antimicrobial therapy. Although there was a trend towards a higher rate of vegetations detected in those with embolic events than in those without, this did not reach statistical significance (84.6% vs 80.9%, P>0.05). Significantly larger vegetations were observed in patients with embolic events as compared to those without embolic events (1.4 cm vs 1.0 cm, P=0.03). The mean plasma concentrations of P-selectin were elevated in patients with embolic events as compared to both patients without embolic events and control subjects (58.69+/-7.49 ng x ml(-1)vs 29.65+/-5.69 ng x ml(-1), P=<0.001 and 58.69+/- 7.49 ng x ml(-1) vs 25.82+/-5.38 ng x ml(-1), P<0.001). Similarly, the patients with embolic events had increased plasma levels of E-selectin compared to those without embolic events and the control group (73.15+/-11.47 ng x ml(-1) vs 42.84+/-8.77 ng x ml(-1), P<0.001 and 73.15+/- 11.47 ng x ml(-1) vs 34.23+/-5.92 ng x ml(-1), P<0.001). CONCLUSION: Determination of these membrane activation molecules may provide useful markers with which to identify patients at high thromboembolic risk from infective endocarditis.

Increased levels of plasma thrombomodulin in patients with acute myocardial infarction who had thrombolytic therapy and achieved successful reperfusion.

BACKGROUND: There is a growing body of evidence from animal and in vitro studies for the existence of reperfusion injury after thrombolytic therapy for acute myocardial infarction (AMI), but the patient data are limited. HYPOTHESIS: We aimed to examine the plasma thrombomodulin (TM) levels as a marker of endothelial injury and to investigate the effect of successful reperfusion on these levels. METHODS: The study included 32 patients who had a first episode of acute myocardial infarction (AMI) and received intravenous streptokinase therapy. RESULTS: Thrombomodulin levels increased significantly at 60 min after thrombolysis compared with the levels before thrombolytic therapy (0 min) in 21 (66%) patients who had successful reperfusion (49.09 +/- 10.51 vs. 25.76 +/- 5.55 ng/ml, p < 0.001). There was no difference between the TM levels at 0 and at 60 min of thrombolysis in the remaining 11 (34%) patients who could not achieve reperfusion (27.81 +/- 6.32 vs. 28.72 +/- 7.28 ng/ml, p = 0.35). CONCLUSION: There was a significant increase in TM levels at 60 min after thrombolysis in a group of patients with AMI who achieved successful reperfusion; this increase may have been caused by the activation/injury of endothelial cells. Data also suggest that the increment in TM levels may be predictive of the potential success of thrombolytic therapy.

Thrombopoietin and mean platelet volume in coronary artery disease.

BACKGROUND: Large platelets are shown to be hemostatically more active. It has been suggested that mean platelet volume (MPV) is increased during acute myocardial infarction (AMI) and unstable angina pectoris (USAP). However, the underlying mechanism of the phenomenon remains unclear. HYPOTHESIS: In this study, platelets, MPV, and thrombopoietin (TP) levels were investigated in patients with coronary artery disease (CAD) and healthy controls. METHODS: Twenty patients with AMI and 20 patients with USAP were included in this study. Seventeen healthy adult subjects served as controls. Venous blood samples of the subjects were drawn within 12 h after admission. Thrombopoietin levels were measured by ELISA and platelet counts and MPV were assayed by autoanalyzer. RESULTS: Patients with AMI and USAP had higher platelet counts than those in the control group. Although the platelet counts were slightly higher in AMI than in USAP, this did not reach statistical significance. Mean platelet volume and levels of TP were found to be elevated in patients with AMI and USAP compared with control subjects (p < 0.001). Thrombopoietin levels were higher in AMI than USAP, but this was not statistically significant. There was a positive correlation between TP levels and MPV values (p < 0.05). CONCLUSION: Increased TP levels may increase both platelet counts and platelet size, resulting in hemostatically more active platelets, which may contribute to the development and progression of CAD.

Diagnosis of coronary artery disease with Tl-201 SPECT in patients with left bundle branch block: importance of alternative interpretation approaches for left anterior descending coronary lesions.

Left bundle branch block (LBBB) is a strong predictor of mortality in the presence of coronary artery disease (CAD). Noninvasive evaluation of CAD in these patients has some difficulties. Exercise-induced electrocardiographic ST segment changes are nondiagnostic, and several scintigraphic studies have reported false-positive anteroseptal and septal perfusion defects up to 80%. The authors aimed to assess the diagnostic accuracy of thallium-201 (Tl-201) exercise myocardial single photon emission computerized tomography (SPECT) in comparison with coronary angiography (CAG) for detection of CAD in patients with LBBB. Seventy-seven consecutive patients suffering from chest pain with complete and permanent LBBB were included in the study. All patients (40 women, 37 men, mean age = 54 +/- 7 years) were studied with Tl-201 exercise SPECT and coronary angiography. Tl-201 exercise SPECT for diagnosis of left anterior descending (LAD) artery lesions was interpreted by using three different approaches: method A (conventional approach), method B (involvement of anterior and septal wall regardless of apical wall), and method C (apical approach: involvement of anterior septal and apical wall). Methods A and B gave a sensitivity of 100% each but a specificity of 47% and 56%, respectively. Although method C gave a higher value of specificity than that of methods A and B (98% vs 47% and 56%, respectively p < 0.05), the sensitivity of method C significantly decreased in respect to methods A and B (33% vs 100% p < 0.01). Isolated septal defects were evaluated separately. Isolated septal defects on exercise Tl-201 SPECT were detected in 11 patients, and none of them had CAD according to CAG results. Isolated septal wall involvement had a sensitivity of 0% and a specificity of 74%. The sensitivity and specificity of Tl-201 SPECT for diagnosis of CAD in the right coronary and left circumflex artery territories were 91% and 89%, respectively. In conclusion, the apical approach increased the specificity and decreased the sensitivity of the test. Isolated septal defects seem to have no value for diagnosis of CAD in patients with left bundle branch block.

Comparison of clinical echocardiographic and hemodynamic characteristics of male and female patients who underwent mitral balloon valvuloplasty.

The clinical echocardiographic and hemodynamic characteristics and outcome of male and female patients before and after valvuloplasty were evaluated. The study population consisted of 34 male and 122 female consecutive patients who successfully underwent percutaneous balloon mitral valvuloplasty (PBMV). Clinical, echocardiographic, and hemodynamic variables were compared between male and female patients. Male patients were significantly older than female patients at the time of PBMV (39 years vs 34 years p < 0.05). Mitral valve score was significantly higher in male patients (p < 0.01). The mitral valve area before PBMV in male patients was significantly less than that in female patients (0.97 +/- 0.22 cm2 vs 1.09 +/- 0.25 cm2, respectively, p < 0.05). The pulmonary artery pressures of female patients before PBMV were higher than those of males (48 mm Hg vs 40 mm Hg, respectively, p < 0.05). The restenosis rates in male and female patients at the end of the follow-up period (38 months) were 20% and 9%, respectively (p < 0.05). In conclusion, male patients are older than female patients at the time of the PBMV procedure, and male patients have worse echocardiographic parameters and restenosis rates than female patients with the exception of pre-procedural pulmonary artery pressure.

Comparison of thallium-201 exercise SPECT and dobutamine stress echocardiography for diagnosis of coronary artery disease in patients with left bundle branch block.

The present study assessed and compared the diagnostic accuracy of thallium-201 (Tl-201) exercise myocardial single photon emission computerised tomography (SPECT) and dobutamine stress echocardiography (DSE) for detection of coronary artery disease (CAD) in patients with left bundle branch block (LBBB). Study population consisted of 26 consecutive patients with permanent LBBB who were suffering from chest pain. Patients (8 women, 18 men mean age = 57+/-8 years) were studied with DSE, Tl-201 SPECT and coronary angiography (CAG). Three different approaches for diagnosis of CAD were used to identify CAD in left arterial descending (LAD) coronary artery territories in scintigraphic studies: (1) Approach A (conventional approach): involvement of septal, and/or anterior, and/or apical wall. (2) Approach B: involvement of anterior and septal wall irrespective of apical wall. (3) Approach C: involvement of septum, anterior and apical wall. DSE gave a sensitivity of 91%, specificity of 92% and accuracy of 92% for diagnosis of CAD in the LAD coronary artery territory. Tl-201 SPECT (conventional approach) gave a sensitivity of 100%, specificity of 42% and diagnostic accuracy of 69% for diagnosis of CAD in the LAD coronary artery territory. Sensitivity, specificity and diagnostic accuracy of approach C were 33, 85 and 57% respectively. The specificity of Tl-201 SPECT significantly increased in approach C when compared with approach A and B (p < 0.02). However sensitivity of the Tl-201 SPECT with approach C showed significant decrease when compared with DSE and approach A and B (p < 0.005). Specificity of DSE for diagnosis of CAD in LAD were significantly higher than those of Tl-201 SPECT regarding the approach A and B (p < 0.01). In conclusion the use of DSE for diagnosis of CAD in patients with LBBB seems to be more suitable than Tl-201 SPECT.

Role of activated protein C resistance in left atrial thrombogenesis in patients with mitral stenosis.

Activated protein C resistance (APC-R) is the most common inherited cause of clinically apparent venous thromboembolism. Previous data indicate that left atrial thrombus (LAT) formation is a common complication in mitral stenosis (MS) and a hypercoagulable state exists in these patients. The aim of this study was to invastigate the association between APC-R and LAT formation in patients with MS. Seventy-seven consecutive patients with rheumatic MS were included in this study. Transesophageal echocardiography was performed on all patients to assess the presence of any thrombus or spontaneous echo contrast (LASEC) in the left atrial cavity or appendage. Thirty four of the patients had LAT and 43 did not. Prevelance of APC-R was smiliar between the two groups of patients with and without LAT (23% vs 16%, p=0.425). LAT(+) patients had higher incidence of atrial fibrillation (AF, 74% vs 51%, p=0.046) and LASEC (71% vs 19%, p<0.001) compared to LAT(-) patients. On multivariate regression analysis, only the presence of LASEC achieved statistical significance as an independent risk factor for LAT formation (p=0.0001, odds ratio=9.589, 95% confidence interval [CI] =3.143-29.251). Because onunivariate analysis both LASEC and AF were associated with LAT, we also compared the prevelance of APC-R in the subgroups of patients who have these risk factors with and without LAT. There was a correlation between the presence of APC-R and LAT in the AF(+) subgroup of MS patients (p=0.033, odds ratio=8.167, 95% CI=1.001-72.812). However, the presence of APC-R was not associated with the increased risk of LAT in LASEC(+) patients (p=0.217, odds ratio=1.200, 95% CI=1.003-1.435). Although the presence of APC-R itself is not an independent risk factor for LAT formation in MS, it may increase the risk of LAT when present in combination with AF (as an additional risk factor) in these patients.