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Biomedical subjects

B I Kuo

Publications and source records attributed to B I Kuo.

At least 37 records · Page 2Linked to original sources
PubMed1998

Sequential variceal pressure measurement by endoscopic needle puncture during maintenance sclerotherapy: the correlation between variceal pressure and variceal rebleeding.

BACKGROUND/AIMS: The risk factors for esophageal variceal rebleeding are little known. Variceal pressure is one of the major determinants of variceal rupture, but the relationship between variceal pressure and variceal rebleeding during maintenance sclerotherapy has not been determined. This study was undertaken to evaluate the relationship between variceal pressure/gradient change and variceal rebleeding during maintenance sclerotherapy. METHODS: Patients with liver cirrhosis and recent esophageal variceal hemorrhage underwent consecutive variceal pressure measurements by direct puncture of the varices before each elective sclerotherapy. RESULTS: In 46 patients, the initial variceal pressure was no different regardless of age, sex, underlying etiology or hepatic reserve. Variceal pressure was higher in large varices, varices with more severe red wale markings, and varices with slower reduction in size during maintenance sclerotherapy. A larger volume of sclerosant was required to eradicate large varices, varices with more severe red wale markings, and varices with slower reduction in size during maintenance sclerotherapy. There was a positive correlation between initial variceal pressure and total amount of sclerosant (r=0.485, p=0.001). Initial variceal pressure was not related to rebleeding. Variceal pressure increased more in patients with rebleeding from varices per se (n=7) than in those without rebleeding (n= 24). There was no difference in pressure change between patients without rebleeding (n=24) and those with rebleeding from variceal ulcers (n=7). CONCLUSIONS: Large varices, severe red color signs and slow reduction in variceal size were associated with higher initial variceal pressure, and more sclerosant was required to eradicate the varices. An increase in variceal pressure during maintenance sclerotherapy indicates a higher risk of variceal rebleeding, but not of variceal ulcer rebleeding.

Aged↗
PubMed1998

Effect of sucralfate granules in suspension on endoscopic variceal sclerotherapy induced ulcer: analysis of the factors determining ulcer healing.

Oesophageal ulcers commonly occur after endoscopic variceal sclerotherapy and usually cause complications and a delay in further sclerotherapy. The aims of this study are to investigate the effect of sucralfate granules in suspension on the treatment of endoscopic variceal sclerotherapy induced ulcer and analyse the factors determining the ulcer healing. Fifty-two patients with oesophageal variceal bleeding received elective endoscopic variceal sclerotherapy. After endoscopically proved oesophageal ulcers, they were randomized to receive either sucralfate granules in suspension (n = 22) or antacid (n = 23). Follow-up endoscopy was performed weekly. Ulcer healing rates were compared between the groups using the log-rank test. Forty-one ulcers receiving sucralfate and 48 ulcers receiving antacid treatment were evaluated. The clinical characteristics of the ulcers were similar in both groups. The ulcers in patients receiving sucralfate healed faster than those receiving antacid (P<0.02). On analysis of factors affecting ulcer healing, ulcers smaller than 1 cm2 (n = 59) appeared to heal faster than those larger than 1 cm2 (n = 30; P= 0.059) and shallow ulcers (n = 46) healed faster than deep ulcers (n = 43; P<0.001). On multifactorial analysis, ulcer depth was the only factor determining ulcer healing. The ulcer healing effects of sucralfate became more prominent when the ulcer was larger than 1.0cm2 (1.7+/-0.6 weeks vs 2.3+/-0.6 weeks, P= 0.011) and deep (1.7+/-0.7 weeks vs 2.5+/-1.0 weeks, P= 0.013) when compared with those receiving antacid. Sucralfate granules in suspension speed the healing of endoscopic variceal sclerotherapy induced ulcer, especially deep and large ulcers.

Adult↗
PubMed1998

Differentiating syndrome X from coronary artery disease by treadmill exercise test in patients with chest pain and exercise-induced myocardial ischemia.

Even though the underlying mechanisms of myocardial ischemia may be different, it is difficult to differentiate syndrome X from coronary artery disease (CAD) by means of the treadmill exercise test in elderly patients with chest pain and exercise-induced myocardial ischemia. One hundred sex- and age-matched patients-42 with syndrome X and 58 with CAD-were studied. Another 10 subjects with atypical chest pain, negative treadmill exercise test, and normal-appearing coronary angiograms served as controls. We evaluated the difference in exercise performance between patients with syndrome X and CAD, and the treadmill exercise test was undertaken with modified Bruce protocol within 2 weeks before coronary angiography. Parameters including time to 1 mm ST segment depression (STD), exercise duration (ED), heart rate (HR), systolic blood pressure, rate-pressure product (RPP), and percentage of age-predicted maximum HR (% HR) at different stages of the test were measured and then compared among the three groups of patients. Compared with CAD patients, syndrome X patients had significantly higher HR, % HR, and RPP at the time of 1 mm STD and at peak exercise. The time to 1 mm STD and ED were longer in syndrome X than in CAD patients. However, ED was shorter and HR, % HR, and RPP at peak exercise were similar in syndrome X patients as compared with control subjects. The new criterion of combined ED (> or =315 seconds) and RPP at peak exercise (> or =24,000 beats x mmHg/min) was found to be highly specific (86%) and moderately sensitive (64%) in differentiating syndrome X from CAD patients. The positive likelihood ratio for this criterion was 4.57 and negative likelihood ratio was 0.42. In conclusion, syndrome X patients had better exercise performance than CAD patients, but less ED and similar workload when compared with control subjects. The new criterion proposed in this study may provide a quick and simple way to differentiate syndrome X from CAD in a group of aged and predominantly male patients with chest pain and positive treadmill exercise test.

Adult↗
PubMed1998

beta-Lactam resistance and beta-lactamase isoforms of Moraxella catarrhalis isolates in Taiwan.

Moraxella catarrhalis is an important pathogen in both upper and lower respiratory tract infections. More than 90% of isolates worldwide produce beta-lactamase. The beta-lactamases produced by M. catarrhalis can be differentiated by isoelectric focusing (IEF) into BRO-1 and BRO-2 patterns. In this study, we investigated the prevalence of various beta-lactamase isoforms in clinical isolates of M. catarrhalis in Taiwan, as well as the relationships of these isoforms with antibiotic resistance. A total of 271 clinical isolates of M. catarrhalis were collected from 12 large medical laboratories in Taiwan from 1 August 1993 to 31 July 1995. The overall prevalence of beta-lactamase production was 98.2% (266 of 271 isolates). Analytical IEF revealed BRO-1 was the most common beta-lactamase pattern among the isolates (238 isolates, 88%); BRO-2 was the only other pattern found, with 32 (12%) isolates. The geometric mean minimum inhibitory concentration of ampicillin for BRO-1 producers was 63-fold higher than that for beta-lactamase-negative isolates, and 6.5-fold higher than that for BRO-2 producers. beta-Lactam antibiotics, such as amoxicillin + clavulanate and the cephalosporins, tested were very active against this species, regardless of whether the isolate produced beta-lactamase or not. In conclusion, beta-lactamase is common among clinical isolates of M. catarrhalis in Taiwan, with BRO-1 being the most common isoform. However, because most isolates tested were still sensitive to amoxicillin + clavulanate and cephalosporins, these agents appear to be reliable alternatives to first-line therapy when M. catarrhalis is contributing to a clinical infection.

Anti-Bacterial Agents↗
PubMed1998

Presence of serum anti-p53 antibodies is associated with pleural effusion and poor prognosis in lung cancer patients.

This study was designed prospectively to evaluate the development of anti-p53 antibodies (Abs) in lung cancer patients in relation to their clinical outcome. Sera, derived from 125 lung cancer patients, consisting of 14 small cell lung cancers (SCLC) and 111 non-SCLCs (NSCLC), were surveyed. The p53-null human NSCLC cell line, NCI-H1299, transfected with a human mutant p53 gene was prepared as the source of p53 antigen for immunoblotting analyses to detect the presence of serum anti-p53 Abs. The control group included sera from 10 healthy adults and 14 patients with benign pulmonary diseases. Clinical data including staging and survival were recorded for statistical analyses. The anti-p53 Abs were found in 8% (10 of 125) of the lung cancer patients studied (8.1% of NSCLC versus 7.1% of SCLC patients), whereas none of the control sera had detectable anti-p53 Abs. The presence of anti-p53 Abs was closely associated with malignant pleural effusions (P = 0.001). The p53 Ab-positive patients had a worse prognosis than the p53 Ab-negative patients (P < 0.02; median survival, 20 versus 41 weeks). In both univariate and multivariate analyses, the tumor extension and probably the presence of anti-p53 Abs were significant predictors for cancer death. The development of anti-p53 Abs (n = 9) was also a predictor for poor survival in patients with malignant effusions (n = 51). In conclusion, the presence of serum anti-p53 Abs is closely associated with malignant pleural effusions in lung cancer patients. It may serve as a negative prognostic factor for survival independent of malignant pleural effusions and tumor staging.

Antibodies, Neoplasm↗
PubMed1997

The health care needs of hospitalized patients with AIDS in Taiwan.

The purpose of this study was to investigate and highlight health care needs as perceived by hospitalized patients with AIDS (PWA) in Taiwan. Convenience sampling was used for this study. Subjects were chosen from one of the medical centers in metropolitan Taipei, Taiwan. Criteria for sampling were that subjects be diagnosed with AIDS, hospitalized without complications of neuropathy, psychosis, or dementia, 12 years old or older, and able to speak Mandarin. Sample size was determined by the saturation principle. Eight subjects were interviewed in depth using a semistructured interview guide. These interviews were tape recorded and transcribed. Content analysis was applied to analyze interview data. The double coding percentage agreement was 0.81, and the intercoder percentage agreement was 0.89. Results revealed the most important health care needs associated with these patients included obtaining information about AIDS, protecting privacy, improving the quality and quantity of health care, securing family members' safety and financial security, and accepting the grief process. These findings suggest that the needs of the PWAs must be identified before nursing care is provided. Furthermore, developing a health care need scale is recommended for patients with AIDS to more effectively assess their health care needs.

Acquired Immunodeficiency Syndrome↗
PubMed1997

Screening for acyclovir-resistant herpes simplex virus isolates from clinical samples.

The ID90 or ID50 values of acyclovir for the herpes simplex virus strains isolated in VGH-Taipei were determined by plaque reduction method. Twenty HSV isolates of 1980's (1980-1985) and thirty of 1990's (1990-1995) were subjected to plaque reduction assay for susceptibility test to acyclovir. There were fifteen HSV isolates of 1990's whose ID90 were higher than those of 1980's, indicating a trend of more acyclovir resistant isolates in 1990's.

Acyclovir↗
PubMed1997

Sequential changes of esophageal motility after endoscopic injection sclerotherapy or variceal ligation for esophageal variceal bleeding: a scintigraphic study.

OBJECTIVE: Endoscopic injection sclerotherapy and variceal ligation are two popular endoscopic methods used to treat esophageal variceal hemorrhage. These two methods have not been compared with regard to esophageal dysfunction after treatment. This is a prospective investigation of esophageal dysmotility after endoscopic injection sclerotherapy and variceal ligation. METHODS: Sequential changes of esophageal motility after endoscopic injection sclerotherapy (n = 25) and variceal ligation (n = 25) were investigated in 50 cirrhotic patients with recent variceal bleeding. Another 22 cirrhotics without esophageal varices were included as controls. Radionuclide esophageal transit tests were performed before initial endoscopic treatment, and 1 and 3 months after variceal eradication. RESULTS: The baseline esophageal transit time was longer in both the sclerotherapy (n = 25, 7.8 +/- 1.4 s) and ligation groups (n = 25, 8.2 +/- 1.8 s) than in controls (n = 22, 6.7 +/- 0.7 s, p < 0.005). The transit time was longer in patients with large varices than in those with small varices (8.3 +/- 1.7 vs. 7.2 +/- 0.7 s, p < 0.05). In the sclerotherapy group, the transit time was prolonged 1 month after variceal eradication, compared with its pretreatment state (n = 20, 7.6 +/- 1.5 vs. 10.0 +/- 2.2 s, p < 0.0001) but was shortened at 3 months compared with 1 month after variceal eradication (n = 12, 10.7 +/- 1.5 vs. 8.6 +/- 2.2 s, p < 0.05). Multiple regression analysis showed that the number of treatment sessions required to eradicate varices was the only significant factor associated with prolonged transit time (p < 0.05). In the ligation group, the transit time changed little at 1 month or 3 months after variceal eradication. CONCLUSIONS: Impairment of esophageal motility can be significant with endoscopic injection sclerotherapy but is reversible. However, endoscopic variceal ligation exerts no significant impact on esophageal motility.

Esophageal and Gastric Varices↗
PubMed1996

Serum cytokine level fluctuations in chemotherapy-induced myelosuppression.

We have reported that serum granulocyte colony-stimulating factor (G-CSF) and interleukin-6 (IL-6) levels rise in patients with chemotherapy-induced myelosuppression. The aim of the present study was to determine whether other cytokines that function at different hematopoietic stages also fluctuate during chemotherapy-induced myelosuppression and whether the extent of cytokine level fluctuations correlate with myelosuppression severity. Fifteen patients participated in the study. Serum levels of stem cell factor (SCF), interleukin (IL)-1 alpha, IL-6, IL-3, granulocyte-macrophage CSF (GM-CSF) and G-CSF were analyzed before chemotherapy and during the myelosuppressive stage and correlations between cytokine levels and myelosuppression severity were examined. The results showed that both serum G-CSF and IL-6 levels rose in patients with chemotherapy-induced myelosuppression. The prechemotherapy serum G-CSF and IL-6 levels correlated well with their respective elevated levels during the myelosuppressive stage. The myelosuppression severity also correlated well with the extent of serum G-CSF level elevation. The serum IL-6 and G-CSF levels during the myelosuppressive stage correlated significantly. Serum SCF levels did not fluctuate significantly during myelosuppression, and IL-1, IL-3 and GM-CSF were rarely detected in serum even after chemotherapy. In the present study, the roles of IL-1 alpha, SCF, IL-3 and GM-CSF chemotherapy-induced myelosuppression were not clear.

Adolescent↗
PubMed1996

The variation of cell type distribution in lung cancer: a study of 10,910 cases at a medical center in Taiwan between 1970 and 1993.

The rise in the incidence of lung cancer has been associated with shifts in histologic distribution. A study was conducted to investigate changes in the cell type distribution in lung cancer in relation to age, sex, and smoking history, based on a retrospective analysis of 10,910 proven cases of lung cancer at the Veterans General Hospital-Taipei during the period from 1970 to 1993. The diagnosis in each case was substantiated by histologic samples from the original tumor site in the lung. Detailed smoking histories were obtained by personal interview at the time of the first admission. Adenocarcinoma (38.3%) was the most common type of lung cancer, followed by squamous cell carcinoma (37.1%) and small cell carcinoma (12.2%). Over the study period, the incidence of squamous cell carcinoma decreased from 46.4% to 36.2% in men (P < 0.005), adenocarcinoma increased from 30% to 36% in men (P = 0.001) and 50.7% to 64.8% in women (P = 0.008), and small cell carcinoma increased from 7% to 14% in men but showed no significant change in women. Adenocarcinoma exhibited a marked increase in both men and women, and surpassed squamous cell carcinoma as the most frequent type of lung cancer. Lung cancer among younger men, and among non-smoking older men and women, was more often adenocarcinoma. Small cell carcinoma showed a significant increase among males, differing from the trend for squamous cell carcinoma in men, though both are strongly associated with smoking. These findings suggest factors other then cigarette smoking could influence the development and distribution of lung cancer.

Adenocarcinoma↗
PubMed1996

Elevation of interleukin-10 levels in malignant pleural effusion.

STUDY OBJECTIVE: Human immunity has been found to have two major components, cellular and humoral immunity. T-helper type 1 (Th1) pathway favors cellular immunity and Th2 pathway favors humoral immunity. Early determination toward Th1 and Th2 cells in the immune response is dependent on the balance between interleukin-12 (IL-12), which favors Th1 responses, and IL-4, which favors Th2 responses. IL-2 and interferon-gamma (IFN-gamma) are produced in the Th1 pathway, and IL-4 and IL-10 are produced in the Th2 pathway. Lack of cellular immunity, IL-2, and IFN-gamma had been reported in malignant pleural effusions. However, to our knowledge, there are no previous reports on other cytokine components involving Th1 or Th2 pathway. The present study was designed to answer these questions. DESIGN: Cytokine levels in peripheral blood and pleural fluid of 21 patients with malignant pleural effusion, including IL-4, IL-10, and IL-12, were analyzed with enzyme-linked immunosorbent assays. Lymphocyte subpopulations of peripheral blood and pleural effusion were also studied by using flow cytometry. MEASUREMENTS AND RESULTS: The results showed a significant increase in IL-10 level as compared with blood samples. IL-4 and IL-12 were below minimal detectable concentrations both in the blood and the effusion. The ratio of pleural helper T cells was significantly higher than in the blood (p = 0.0002). The ratio of pleural natural killer (NK) cells was significantly lower than in the blood (p = 0.0001). The ratio of pleural suppressor T cells was lower than blood with borderline significance (p = 0.0522). No significant change in B-lymphocyte ratio between blood and pleural effusion was found (p = 0.2471). There was no correlation between difference in IL-10 level and lymphocyte subpopulation of pleural effusion and blood samples. CONCLUSIONS: Helper T-cell subpopulations were increased while NK and suppressor T-cell subpopulations were decreased in malignant pleural effusions. The decrease in NK cell subpopulations with elevated IL-10 and minimal IL-12 concentration in neoplastic pleural effusion would suggest the usage of IL-12 or antibody of IL-10 to improve local cellular immunity. Further study is needed.

Adult↗
PubMed1996

Seasonal variation in the incidence of peptic ulcer and esophageal variceal bleeding in Taiwan.

BACKGROUND: Seasonal variation of peptic ulcer and peptic ulcer bleeding has been reported in many western countries. To investigate the seasonal variation of peptic ulcer (PU) and esophageal variceal (EV) bleeding in Taiwan, this retrospective study was conducted. METHODS: Seven hundred and forty-six cases of gastric ulcer (GU) bleeding, 777 cases of duodenal ulcer (DU) bleeding and 264 cases of EV bleeding were recruited from January 1, 1991 to December 31, 1992. Patients were sent to the Medical Emergency Room (MER) for hematemesis and/or melena. Upper gastrointestinal (UGI) endoscopic examinations were completed within 24 hours for all patients. RESULTS: Significant seasonal variation was found in the incidence of PU and EV bleeding. PU bleeding was most often seen in March and EV bleeding was most often seen in February. CONCLUSIONS: The possible mechanism for the cyclic change of PU and EV bleeding is unclear, but clearly more manpower is needed during the months of February and March for better management of the increasing number of cases of PU and EV bleeding.

Aged↗
PubMed1996

Clinical implications of the white nipple sign and its role in the diagnosis of esophageal variceal hemorrhage.

OBJECTIVE: Differentiation of esophageal variceal hemorrhage from other sources of the GI tract is often difficult. This is a prospective investigation of the significance of the white nipple sign in patients with recent esophageal variceal hemorrhage. METHODS: One hundred sixty-six patients with recent variceal hemorrhage were prospectively studied with respect to presence or absence of the white nipple sign and other stigmata of hemorrhage and compared with 100 patients with known varices but without a clinical history of bleeding. RESULTS: The white nipple sign correlated positively with severity of bleeding (patients required more blood transfusion), hematemesis, and signs of shock. Patients with the white nipple sign also tended to undergo emergency endoscopy and have active bleeding at the time of endoscopy. There was no correlation between rebleeding rate after endoscopic therapy and presence of the white nipple sign. Appearance of the white nipple sign was closely related to the timing of endoscopy (p < 0.0001). The sensitivity and specificity of the white nipple sign in the diagnosis of esophageal variceal hemorrhage were 21 and 100%, respectively, compared with 100 and 54% for the red color sign. Furthermore, the sensitivity of the white nipple sign increased with shorter times between bleeding and endoscopy. CONCLUSIONS: In patients with upper GI bleeding, the white nipple sign suggests that the varices bled recently and that the bleeding was severe. However, it has no predictive value for rebleeding after endoscopic therapy. Earlier endoscopy (i.e., within 24 h of bleeding) is suggested to improve the diagnostic rate of esophageal variceal hemorrhage.

Case-Control Studies↗
PubMed1996

Lack of NK cells and related cytokines in pleural effusion.

BACKGROUND: Relatively low number and activity of natural-killer (NK) cells have been reported in malignant pleural effusions. However, there has been no report on NK cells related cytokines. METHODS: Lymphocyte subpopulations were studied in 30 cases of pleural effusion with various etiologies, along with peripheral blood, by using flow cytometry. The related cytokine levels in peripheral blood and pleural fluid, including IL-1 alpha, IL-4 and IL-12, were also analyzed with ELISA assays. RESULTS: The results showed significant increase of T-helper cell subpopulation in pleural effusion of various etiologies. No obvious change of B-lymphocyte subpopulation between peripheral blood and pleural effusion was found. IL-4 was undetectable in both peripheral blood and pleural fluid in most cases. IL-1 alpha was detectable in some cases and the level was highest in pleural fluid of empyema. Decreased NK cells were found in most cases of pleural effusion and accompanied by undetectable IL-12 both in pleural fluid and peripheral blood. The only one case with detectable IL-12 concentration in pleural fluid was the one with tuberculous pleurisy. CONCLUSIONS: Increased T-helper cell subpopulation and decreased NK cell subpopulation were found in pleural effusion of various etiologies. In spite of the small series of our patients, the decrease of NK cell subpopulation and the undetectable IL-12 concentration in pleural effusion deserves further investigations.

Adult↗
PubMed1995

Changes in portal hypertensive gastropathy after endoscopic variceal sclerotherapy or ligation: an endoscopic observation.

To determine the effect of endoscopic variceal sclerotherapy or ligation on portal hypertensive gastropathy, 90 cirrhotic patients with esophageal variceal bleeding were randomized to receive sclerotherapy (n = 44) or ligation (n = 46). Follow-up endoscopic observations of the gastric mucosa were recorded at 3-month intervals after variceal eradication. Clinical characteristics in both groups were similar. Probability for a change in the severity of portal hypertensive gastropathy was not related to method of eradication. Most cases of portal hypertensive gastropathy that changed in severity returned to baseline status with time, but the return was faster after ligation than after sclerotherapy. According to the results of multivariate analyses, sclerosant volume was the only factor associated with a significant difference between the group with static gastropathy (n = 15) and that with dynamic change in gastropathy (n = 23) after sclerotherapy. No relevant factors were found in the patients receiving ligation. We conclude that changes in the severity of portal hypertensive gastropathy after endoscopic variceal sclerotherapy or ligation are reversible. Most cases of gastropathy return to baseline status sooner or later.

Esophageal and Gastric Varices↗
PubMed1995

The Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) as a screening tool for dementia for a predominantly illiterate Chinese population.

The Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) provides ratings of an individual's changes in everyday cognitive functions during the previous 10 years. Original studies conducted in Australia showed that its score was not influenced by the subjects' educational backgrounds and that it performed at least as well as the Mini-Mental State Examination (MMSE) as a screening instrument for dementia. The subjects of the present study were Chinese and included 399 community residents and 61 dementia patients. Their ages ranged from 50 to 92 years; their education levels ranged from 0 to 19 years, and 63% of them had never attended school. We administered the IQCODE to informants and the Cognitive Abilities Screening Instrument (CASI), from which a CASI-estimated score of the MMSE (MMSE-CE) can be obtained, to the subjects. The diagnosis of dementia was made independently by physicians according to the DSM-III-R criteria based on semistructured interview and testing, neurologic examination, and standardized assessments of cerebral vascular disease, Parkinson's disease, and depression. The Chinese IQCODE showed no association with the subjects' education level or gender, low association with their age, and moderately high association with their MMSE-CE score. The area under the receiver operating characteristic curve of the IQCODE was significantly larger than that of the MMSE-CE for the whole group and for the subgroup with 1 to 19 years of education but not for the subgroup with 0 years of education. Nine of the 26 items of the IQCODE could be deleted without appreciable reduction in sensitivity and specificity. The IQCODE (1) can be shortened to 17 items, (2) had good cross-cultural applicability, and (3) was better than the MMSE-CE as a screening tool for dementia in a population with large variation in educational backgrounds.

Age Factors↗
PubMed1995

The effects of accumulated experience on radiofrequency ablation of accessory pathways.

Increasing experience in radiofrequency ablation for accessory pathways appears to reduce the procedure time, radiation time and radiofrequency pulse number, and results in a higher success rate. However, the effect of a learning curve on this procedure from the perspective of location and conduction direction of accessory pathways has not been reported before. The purpose of this study was to determine the effect of accumulated experience on the outcomes of radiofrequency ablation for accessory pathways and on the duration of the procedure parameters by analyzing the results of a dedicated ablation team. The first 512 patients with a single accessory pathway treated in this laboratory were included for analysis of the procedure parameters with respect to locations and conduction directions of accessory pathways. The results showed that the average procedure time, radiation time, and radiofrequency pulse number differed significantly among the different subgroups (left free wall, right free wall, posteroseptal and anteromidseptal location; manifest or concealed conduction). All subgroups except the anteromidseptal pathways showed a significant improvement of the procedure parameters with increased ablation experience. Although the initial rate of improvement was similar among the different subgroups, the rate of improvement in left free wall pathways nearly reached a plateau after 120 ablation procedures. Thus it was concluded that a certain number of ablation procedures was necessary before achievement of a high success rate with shorter procedure and radiation times and a lower radiofrequency pulse number.

Catheter Ablation↗