Comparison of Normal Sinus Rhythm and Pacing Rate in Children with Minute Ventilation Single Chamber Rate Adaptive Permanent Pacemakers

Rate adaptive pacemakers are used to achieve a better cardiac performance during exercise by increasing the heart rate and cardiac output. The ideal rate adaptive sensor should be able to mimic sinus node modulation under various degrees of exercise and other metabolic needs. Minute ventilation sensing has proven to be one of the most accurate sensor systems. In this study, alterations in sinus rhythm and pacing rates during daily life conditions in 11 children (median age 11 years, range 6–14 years) with minute ventilation single chamber pacemakers were investigated. Correlation of sinus rhythm with pacing rates was assessed. ECG records were obtained from 24–hour Holter monitoring. Average rates of five consecutive P waves and pace waves were determined every half hour. The average of the two values was then used to determine hourly rates. Correlation coefficients between the sinus rhythm and pacing rates were calculated. In nine patients, pacing rates correlated well to sinus rhythm (range 0.6793–0.9558. P < 0.001 and P < 0.05), whereas in two cases correlation was not sufficient (P > 0.05). Most of the patients, in whom rate response factor (RRF) measurements during peak exercise by treadmill with cnronotropic assessment exercise protocol were performed and pacemakers were programmed to these parameters, had more appropriate ventricular rates compared to spontaneous sinus rates. In these patients mean RRF value was 15.3 ± 2.7 (range 12–20, median 15). This study shows that during daily activities minute ventilation rate adaptive pacemakers can achieve pacing rates well correlated to sinus rhythm that reflects the physiological heart rate in children.     

Comparison of Sensitivity and Specificity of Tilt Protocols with and without Isoproterenol in Children with Unexplained Syncope

Head-up tilt testing with or without isoproterenol is extensively used in the evaluation of patients with unexplained syncope. However, sensitivity and specificity of tilt protocols with and without isoproterenol have not been clarified in children, due to lack of age matched control subjects. This study was designed to assess and to compare the sensitivity and specificity of tilting alone and tilting in conjunction with isoproterenol. Thirty children with unexplained syncope (group I) and 15 age-matched control subjects (control group I) underwent successive 60° head-up tilts for 10 minutes during infusions of 0.02, 0.04, and 0.06 μg/kg/min of isoproterenol, after a baseline tilt to 60° for 25 minutes. Also, 35 children (group II) with unexplained syncope and 15 healthy control subjects (control group II) were evaluated by head-up tilt to 60° for 45 minutes without an infusion of isoproterenol. In response to tilt protocol with graded isoproterenol, 23 (76.6%) of the patients in group I and 2 of the 25 (13.3%) control subjects developed syncope. Accordingly, the sensitivity of tilt testing with isoproterenol was 76.6%, and its specificity was 86.7%. Tilt testing without isoproterenol was positive in 17 (48.5%) of the patients in group II but in only 1 of the 15 (6.6%) control subjects. Thus, sensitivity and specificity of tilt testing without isoproterenol were 48.5% and 93.4%, respectively. The mean heart rate and systolic blood pressure decreased significantly (P < 0.001) in all tilt positive patients during syncope. In conclusion, the head-up tilt test is a valuable diagnostic test in the evaluation of children with unexplained syncope, and isoproterenol is likely to increase the sensitivity of the test without decreasing its specificity.     

Skeletal carcinomatosis in endometrial clear cell carcinoma at initial presentation: a case report

Bone metastasis is frequently seen in different solid tissue malignancies. However, it is a very rare entity in endometrial cancers and most of the previous reports were localized to a single bone. To the best of our knowledge, this is the first report of a case with disseminated bone metastasis from endometrial clear cell carcinoma. A 69-year-old, multiparous woman presented with the complaint of postmenopausal bleeding. Diagnostic workup revealed endometrial clear cell carcinoma. After comprehensive surgical staging, the patient was found to be at FIGO stage IIIC. Three weeks after the operation, an intractable back pain developed. Direct graphics of the lumbosacral region were suspicious of metastasis, and further evaluation of the patient revealed metastasis in multiple bones including calvarium, thoracolumbal vertebrae, pelvic bones, costae, collum of the right femur, and trochanter major of the left femur. Bone metastasis in endometrial clear cell carcinoma may be seen at initial presentation and may involve multiple bones. Whole-body scanning with scintigraphic evaluation is a reasonable approach to evaluate the extension of the bone involvement. Further studies are needed to elucidate the true incidence and management of bone metastasis in endometrial clear cell carcinoma.     

Role of adenosine in the diagnosis and treatment of tachyarrhythmias in pediatric patients

Tachyarrhythmias are common rhythm disturbances in infants and children. Despite the availability of diagnostic criteria arrhythmias are sometimes commonly misdiagnosed. Recent reports suggest that an endogenous purine nucleoside, adenosine, has a diagnostic effect in narrow QRS complex tachycardias, in addition to terminating supraventricular tachycardia involving the atrioventricular node. This report reviews the authors' experience with the use of adenosine for diagnosis of narrow and wide complex tachyarrhythmias in children. Adenosine was administered to 43 patients with several types of tachyarrhythmias (mean age, 8.3 ± 5.24 years). Nineteen patients had structural or acquired heart disease. Of the 43 patients there were 28 (65%) several different types of narrow QRS complex tachycardia and 14 (33%) ventricular arrhythmias. One patient (2%) had long QT. Adenosine terminated supraventricular tachycardia, in 11 of 12 patients (92%), ventricular tachycardia in five of eight patients (63%), and transiently terminated premature ventricular contractions in two of six patients (33%). The diagnostic ability of adenosine was perfect in eight supraventricular tachycardia. In these eight cases the tachycardia mechanism was unclear before the administration of adenosine, which demonstrated three cases of sinus tachycardia, three of atrial flutter, one of atrial fibrillation and one of atrial fibrilloflutter. Confirmation of the primary diagnosis by adenosine was perfect in five tachyarrhythmias including three cases of atrial flutter, one of atrial fibrillation and one of ectopic atrial tachycardia. The average effective dose of adenosine was 212 μg/kg (range, 100–400 μg/kg). There were no serious side-effects except transient dyspnea, chest pain and flushing. These findings demonstrate adenosine to be helpful and safe in the diagnosis of tachyarrhythmias.     

Transcatheter closure of patent ductus arteriosus using controlled-release coils

Controlled-release coils have become available recently for the closure of patent ductus arteriosus (PDA). Transcatheter closure of patent arterial ducts was attempted in 13 patients, ranging in age from 5 months to 15 years, mean 4.1 years. Implantation of controlled-release PDA coils was attempted via the femoral artery through 5 Fr catheters in all cases except one, in whom both the femoral arterial and venous routes were used. The procedure was successful in 10 of the 13 patients. In these, the pulmonary artery systolic pressure ranged between 25 and 42 mmHg and the duct diameter varied from 1.5 to 6 mm at its narrowest point. Six of the patients received a single coil. Two coils were inserted in three patients and three coils in one patient. In three patients the ducts were too large for safe release of the coils, despite attempted implantation of up to three coils simultaneously. These coils were easily withdrawn into the catheter Immediately at the end of the procedure, the duct was completely occluded in nine of the 10 patients, and in one patient there was a small residual flow. The procedure time varied between 35 min and 2.5 h, mean 81 min and the fluoroscopy time varied from 5 to 78 min, mean 25 min. None of the patients experienced hemorrhage, diminished lower extremity pulse, hemolysis or infection. In one patient, a 5 mm coil embolized into the right pulmonary artery soon after release. It was retrieved with a snare, then 8 mm and a 5 mm coil were implanted satisfactorily in the arterial duct. At follow-up by color Doppler echocardiography, the duct was completely occluded in all patients. Transcatheter closure of patent arterial ducts by controlled-release PDA coils is effective and safe. Even when more than one coil is inserted, it is still cheaper than transcatheter umbrella closure. This method is therefore of great value, particularly in less affluent countries.     

Cyclooxygenase-2 expression in cervical intraepithelial neoplasia III and squamous cell cervical carcinoma, and its correlation with clinicopathologic variables

The objective of the study was to compare cyclooxygenase-2 (COX-2) expression in cervical intraepithelial neoplasia III (CIN III) and squamous cell carcinoma (SCC) of the cervix, and its correlation with clinicopathologic factors of SCC with a review of the available literature. This study included 25 patients with CIN III and 67 patients with stage I-IIa SCC. All patients in the SCC group were treated with radical hysterectomy plus pelvic and para-aortic lymphadenectomy and postoperative chemoradiotherapy based on their histopathologic risk factors. Immunohistochemical analysis was performed on paraffin-embedded sections with COX-2 antibody. COX-2 expression in the SCC group was significantly higher than in the CIN III group (55.2% [37/67] vs 24% [6/25]; P= 0.008). Significantly higher expression of COX-2 was observed in patients with lymphovascular space invasion (LVSI) compared to patients without LVSI (61.9% [34/55] vs 33.3% [3/9]; P= 0.02). Additionally, patients with tumor sizes >4 cm had significantly higher COX-2 expression than patients with tumor sizes <4 cm (65.9% [27/41] vs 39% [10/26] P= 0.028). There was no significant relationship with respect to COX-2 expression and parametrial involvement, lymph node metastasis, recurrences, and survival. In multivariate analysis, LVSI was the only statistically significant determinant for COX-2 expression (P= 0.024; OR = 2.35; 95% CI = 1.1-4.9). Our results and a review of the literature both suggest that COX-2 expression may have a role in the development and progression of CIN III and it is related to some clinicopathologic variables of cervical carcinoma. Further studies are needed to clarify the role of COX-2 inhibitors in the management of CIN and SCC.     

Retroperitoneal leiomyomatosis: a case report

Leiomyoma is the most common benign solid pelvic tumor seen in women. It is most commonly located in the uterus and gastrointestinal tract, but it can originate wherever smooth muscle cells exist. Although it has been reported in various atypical localizations, they are extremely rare in the retroperitoneum. Also, preoperative diagnosis is often difficult in retroperitoneal tumors. Imaging studies may demonstrate the retroperitoneal tumors; however, exact diagnosis cannot be established by imaging methods alone. Here, we report a case with retroperitoneal leiomyomatosis diagnosed by preoperative ultrasonography-guided fine-needle biopsy.