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PubMed2002

Natural history of Brugada syndrome: insights for risk stratification and management.

BACKGROUND: Treatment of patients with Brugada syndrome is complicated by the incomplete information on the natural history of the disease related to the small number of cases reported. Furthermore, the value of programmed electrical stimulation (PES) for risk stratification is highly debated. The objective of this study was to search for novel parameters to identify patients at risk of sudden death. METHODS AND RESULTS: Clinical data were collected for 200 patients (152 men, 48 women; age, 41+/-18 years) and stored in a dedicated database. Genetic analysis was performed, and mutations on the SCN5A gene were identified in 28 of 130 probands and in 56 of 121 family members. The life-table method of Kaplan-Meier used to define the cardiac arrest-free interval in patients undergoing PES failed to demonstrate an association between PES inducibility and spontaneous occurrence of ventricular fibrillation. Multivariate Cox regression analysis showed that after adjusting for sex, family history of sudden death, and SCN5A mutations, the combined presence of a spontaneous ST-segment elevation in leads V1 through V3 and the history of syncope identifies subjects at risk of cardiac arrest (HR, 6.4; 95% CI, 1.9 to 21; P<0.002). CONCLUSIONS: The information on the natural history of patients obtained in this study allowed elaboration of a risk-stratification scheme to quantify the risk for sudden cardiac death and to target the use of the implantable cardioverter-defibrillator.

Adolescent↗
PubMed1999

Lifetime risk of developing coronary heart disease.

BACKGROUND: The lifetime risk of developing coronary heart disease has not been estimated in a general population. We investigated the lifetime risks of initial coronary events at different ages. METHODS: We assessed data for 7733 participants in the Framingham Heart Study, who had been examined at least once at age 40-94 years between 1971 and 1975, found to be free of coronary heart disease, and then followed up. We estimated the lifetime risks of coronary heart disease (angina pectoris, coronary insufficiency, myocardial infarction, or death from coronary heart disease) by multiple-decrement life-table methods. FINDINGS: The 7733 patients were followed up for a total of 109,948 person-years. Overall, 1157 participants developed coronary heart disease. 1312 died from non-coronary heart disease causes. Lifetime risk of coronary heart disease at age 40 years was 48.6% (95% CI 45.8-51.3) for men and 31.7% (29.2-34.2) for women. At age 70 years, lifetime risk was 34.9% (31.2-38.7) for men and 24.2% (21.4-27.0) for women. After we excluded isolated angina pectoris as an initial event, the lifetime risk of coronary artery disease events at age 40 years was 42.4% for men and 24.9% for women. INTERPRETATION: Lifetime risk at age 40 years is one in two for men and one in three for women. Even at age 70 years it is one in three for men and one in four for women. This knowledge may promote efforts in education, screening, and treatment for prevention of coronary heart disease in younger and older patients.

Adult↗
PubMed1994

Ethnic differences in the sudden infant death syndrome: what we can learn from immigrants to the UK.

AIMS: To compare the effect of potential maternal and birth factors on rates of sudden infant death syndrome (SIDS) within and between infants born to mothers of different ethnic groups. METHODS: Routinely collected obstetric, child health data relating to 39,101 residents of three East London Districts born in 1989-1990 were obtained. These were matched with 312 death registration records to validate death and add registered cause of death. Mortality rates were calculated in the usual way, and using life-table methods. RESULTS: These related to six ethnic groups, the largest of which were Anglo-European and Bangladeshi. Low birth-weight was the only factor associated with a greater risk of SIDS in all ethnic groups. Maternal smoking was uncommon amongst all Asian groups and African mothers, and rates of SIDS were uniformly low amongst non-smokers in all ethnic groups except Pakistanis. Adjustment for maternal age, parity, gestational age and birthweight would widen the differences between risk of SIDS observed between Anglo-Europeans and Bangladeshi infants. CONCLUSIONS: The study has demonstrated that local data is more timely and of greater detail than that available nationally. Of the risk factors considered, smoking reported during pregnancy is the most commonly encountered and is particularly associated with deaths attributed to SIDS.

Africa↗
PubMed2004

Risk of cancer from diagnostic X-rays: estimates for the UK and 14 other countries.

BACKGROUND: Diagnostic X-rays are the largest man-made source of radiation exposure to the general population, contributing about 14% of the total annual exposure worldwide from all sources. Although diagnostic X-rays provide great benefits, that their use involves some small risk of developing cancer is generally accepted. Our aim was to estimate the extent of this risk on the basis of the annual number of diagnostic X-rays undertaken in the UK and in 14 other developed countries. METHODS: We combined data on the frequency of diagnostic X-ray use, estimated radiation doses from X-rays to individual body organs, and risk models, based mainly on the Japanese atomic bomb survivors, with population-based cancer incidence rates and mortality rates for all causes of death, using life table methods. FINDINGS: Our results indicate that in the UK about 0.6% of the cumulative risk of cancer to age 75 years could be attributable to diagnostic X-rays. This percentage is equivalent to about 700 cases of cancer per year. In 13 other developed countries, estimates of the attributable risk ranged from 0.6% to 1.8%, whereas in Japan, which had the highest estimated annual exposure frequency in the world, it was more than 3%. INTERPRETATION: We provide detailed estimates of the cancer risk from diagnostic X-rays. The calculations involved a number of assumptions and so are inevitably subject to considerable uncertainty. The possibility that we have overestimated the risks cannot be ruled out, but that we have underestimated them substantially seems unlikely.

Adolescent↗
PubMed1985

[A statistical study on the survival rate].

The survival rate is used as a criterion in evaluation of cancer treatment. This paper describes several view of various calculating methods for the survival rate by using a computer filing system of patients' records of cancer therapy as follow; Crude survival rate should not be used in usual follow-up study, if possible, because different results obtained from different determination for right censored cases. In case of value of the life table method or relative survival rate changed in short terms, re-computation by the more short interval (for example, from yearly monthly) must be analyzed for the reason of the quick exchange. According with improvement of the survival rate of cancer therapy, it is important to remark for the complication of normal tissues by radiation therapy at the end of treatment and during follow-up observation. Therefore, we proposed a new concept which is named "Cumulative effective survival rate" and is calculated by multiplying the average of cumulative weighted factors of complications of various normal tissues to the relative survival rate.

Actuarial Analysis↗
PubMed1993

Long-term outcome after hospitalization for small-bowel obstruction.

OBJECTIVE: To determine the recurrence rate of small-bowel obstruction and differences in recurrence rates stratified by cause of obstruction and method of treatment. DESIGN: Retrospective chart review with average follow-up of 53 months (range, 0 to 129 months). SETTING: Combined community hospital/clinic tertiary referral center. PATIENTS: 309 consecutive patients with documented mechanical small-bowel obstruction hospitalized from 1981 to 1986. MAIN OUTCOME MEASURES: Recurrence rates by the actuarial life-table method and comparisons made by the Wilcoxon and log-rank tests. RESULTS: Recurrent obstruction developed in 34% of all patients by 4 years and in 42% by 10 years. Recurrence rates were 29% and 53% in the patients who did and did not undergo surgery (P = .002). The recurrence rate in patients with surgery was 56% for malignant neoplasms, 28% for adhesions, and 0% for hernia. Recurrence rates were 50% and 40% for patients with and without prior multiple obstructions (P = .7). CONCLUSIONS: The long-term risk of recurrent small-bowel obstruction is high. The risk is lessened by operation but not eliminated. The risk of recurrence increases with longer duration of follow-up, but most recurrences occur within 4 years. Multiple prior obstructions did not increase the risk of future obstruction.

Adolescent↗
PubMed1975

Vascular access for dialysis. Technics and results with newer methods.

Over a five year period, 114 patients had one or more secondary operations for access to the circulation for hemodialysis, these being a Thomas femoral shunt, saphenous vein graft, or Sparks mandril graft. The patient group was different from the general dialysis population, containing more females, more patients with diabetes, and more patients with collagen-vascular disease. Comparing duration of utility by the life table method for each technic, the femoral shunt lasted longest but with a high incidence of septic complications, the mandril graft was intermediate, and the saphenous vein graft least durable in use. The mandril is considered a tentative first choice for secondary access when the required maturation time is available.

Arteriovenous Shunt, Surgical↗
PubMed1997

Randomised double blind controlled study of recurrence of gastric ulcer after treatment for eradication of Helicobacter pylori infection.

OBJECTIVE: To determine whether eradication of Helicobacter pylori infection reduces recurrence of benign gastric ulceration. DESIGN: Randomised, double blind, controlled study. Patients were randomised in a 1:2 ratio to either omeprazole 40 mg once daily for eight weeks or the same treatment plus amoxycillin 750 mg twice daily for weeks 7 and 8. A 12 month untreated follow up ensued. SETTING: Teaching and district general hospitals between 1991 and 1994. SUBJECTS: 107 patients with benign gastric ulcer associated with H pylori. MAIN OUTCOME MEASURES: Endoscopically confirmed relapse with gastric ulcer (analysed with life table methods), H pylori eradication, and healing of gastric ulcers (Mantel-Haenszel test). RESULTS: 172 patients were enrolled. Malignancy was diagnosed in 19; 24 were not infected with H pylori; four withdrew because of adverse events; and 18 failed to attend for start of treatment, leaving 107 patients eligible for analysis (35 omeprazole alone; 72 omeprazole plus amoxycillin). In the omeprazole/amoxycillin group 93% (67/72; 95% confidence interval 84% to 98%) of gastric ulcers healed and 83% (29/35; 66% to 94%) in the omeprazole group (P = 0.103). Eradication of H pylori was 58% (42/72; 46% to 70%) and 6% (2/35; 1% to 19%) (P < 0.001) and relapse after treatment was 22% (16/72) and 49% (17/35) (life table analysis, P < 0.001), in the two groups, respectively. The recurrence rates were 7% (3/44) after successful H pylori eradication and 48% (30/63) in those who continued to be infected (P < 0.001). CONCLUSIONS: Eradication of H pylori reduces relapse with gastric ulcer over one year. Eradication rates achieved with this regimen, however, are too low for it to be recommended for routine use.

Amoxicillin↗
PubMed1999

Endovascular versus surgical treatment for thrombosed hemodialysis grafts: A prospective, randomized study.

PURPOSE: The objective of this study was to compare clinical outcome and costs for two widely used treatment strategies for hemodialysis graft thrombosis. METHODS: During a 4-year period, 80 patients with thrombosed dialysis grafts were randomly assigned to surgical thrombectomy with or without graft revision (SURG) or thrombolytic therapy with urokinase with the pulse-spray technique (ENDO), with adjunctive percutaneous transluminal angioplasty as indicated. All the procedures were performed in an endovascular operating suite with fistulography. The clinical and cost data were tabulated, and the outcome was analyzed with the life-table method. RESULTS: Fifty-six women and 24 men ranged in age from 33 to 90 years (mean, 63.7 years). The patients had undergone a mean of 2.8 prior access procedures in the ipsilateral extremity. All the grafts were upper extremity expanded polytetrafluoroethylene grafts. Lesions that were presumed to be the primary cause of graft thrombosis were identified in 73 of 80 grafts, and 60 of these were at the venous anastomosis. The procedure time averaged 99 minutes for the patients in the SURG group and 113 minutes for the patients in the ENDO group (P =.12). Eleven patients in the ENDO group crossed over to surgical revision as compared with two patients in the SURG group who required adjunctive percutaneous transluminal angioplasty (P =.005). The mean cost of treatment (including room and supply costs but not professional fees) was significantly higher for the ENDO group than for the SURG group ($2945 vs $1512; P <.001). There were no procedure-related complications in either group. At a median follow-up time of 24 months, there was no difference in primary or assisted primary patency between groups, which averaged 6 and 7 months, respectively. CONCLUSION: Although thrombolytic therapy combined with endovascular treatment can extend the life of dialysis grafts with results similar to surgical revision, there is a high rate of technical failure necessitating surgery and a substantially higher cost for thrombolysis.

Adult↗
PubMed2003

Carotid-carotid crossover bypass: is it a durable procedure?

PURPOSE: Reconstruction of a diseased common carotid artery may necessitate direct repair via aortic artery-based revascularization. However, carotid-carotid artery crossover grafting is an alternative extra-anatomic option that obviates the need for median sternotomy. We analyzed our results with carotid-carotid artery crossover bypass surgery. METHODS: Data were analyzed for all patients undergoing carotid-carotid crossover bypass surgery from 1995 to 2000. Data on patient demographics, indications for surgery, perioperative morbidity and mortality, and graft patency were retrieved from a vascular surgery data base and hospital records. Stroke-free survival and graft patency were determined with life table methods. RESULTS: Over 5 years, 24 carotid-carotid artery crossover bypass procedures were performed to treat both symptomatic (n = 19, 79%) and asymptomatic (n = 5, 17%) disease. Nine procedures (38%) were performed in men, 3 (13%) in patients with diabetes, 12 (50%) in active smokers, and 2 in patients with a history of Takayasu arteritis. Patient mean age was 63 years (range, 38-79 years). Twenty-three patients (96%) received polytetrafluoroethylene conduit grafts, and the remaining patients received vein grafts. Ten (42%) patients underwent concomitant endarterectomy. There were no perioperative deaths. One patient (4%) had asymptomatic early occlusion, one had transient neurologic deficit (4%), one (4%) required additional surgery because of bleeding, and one (4%) had a perioperative cerebrovascular accident (stroke). Three (17%) asymptomatic late occlusions were identified at 11, 57, and 64 months, respectively. Mean follow-up was 30 months (range, 1-70 months). Primary patency was 88%, and secondary patency was 92% at 3 years. Stroke-free survival was 94% at 4 years. CONCLUSION: Carotid-carotid artery crossover bypass surgery is a safe and durable procedure. Its use precludes the need for median sternotomy and provides acceptable stroke-free survival.

Adult↗
PubMed1996

[The long-term effect of day care rehabilitation on individuals with dementia].

In the treatment of senile dementia, rehabilitation rather than drugs, could result in more positive long-term effects. A Day Care program designed for individuals with Senile Dementia of the Alzheimer type (SDAT) and Vascular Dementia (VD:MID and BD), activates the brain through memory training, creative arts therapy, physical activity, and social interaction. The objective of this study is to determine if Day Care can modify the patients intellectual decline or even alter the natural course of the dementing illness. 135 SDAT and 213 VD patients were studied over three years. ADL (Activities of Daily Living) measurements were evaluated by the Barthel Index and cognitive measurements by the NM-scale. The Wilcoxon test and the Sign test were carried out using the BI and NM-scale scores. These results indicated a decline or arrest in the progression of SDAT and VD as determined by the multiple logistical models. The 8 variables (risk factors, medication, age at onset, self-rehabilitation, family support, sex, grade of dementia and Day Care) influence on the survival curves was calculated using the Kaplan-Meire Life table method. The Cox proportional hazard analysis was then used to examine the relationship between the 8 variables and dementia. The significantly positive results from these four analyses of the ADL and cognitive measurements indicate that Day Care programs clearly retards the progression of intellectual decline in dementia patients and improves the quality of life (QOL) in all cases. In VD patients the mortality rate was notably decreased through Day Care. These results make one consider the benefits of introducing such programs into society as a strong treatment against the onset of dementia developing into severe, dehabilitating dementia. However a healthy diet, a physically and mentally active life, as well as early diagnosis, are the best preventions against dementia.

Activities of Daily Living↗
PubMed2001

[Late results after eversion endarterectomy of the internal carotid artery].

OBJECTIVES: The eversion endarterectomy of the internal carotid artery was introduced in Hungary in 1991. The aim of this study was to define the long-term restenosis rate of this new method. MATERIALS AND METHODS: Between 1991 and 1993, 171 operations were performed by one surgeon on 151 patients: 109 patients had enough compliance to take part in long-term follow-up, which included annual physical and ultrasound (Ultramark 9) investigations. Restenosis rate and plaque morphology was defined. Survival and patency rates were calculated by life-table method. RESULTS: The perioperative combined stroke morbidity and mortality rate was 0.8%. The 5-year patient survival rate was 85%, the recurrent stenosis free rate was 88%/5 years, and 9% of the patients had restenosis greater than 70% in this period. The plaque morphology showed calcification in 1 case. Two patients needed 3 reoperations (2.4%). Plaque histology showed myointimal hyperplasia in every 3 cases. CONCLUSIONS: Comparing our results to the literature (2-34% restenosis rate) it seems to be acceptable and encouraging for the future. The ultrasound and histological findings suggest that arteriosclerosis does not play significant role in development of restenosis after the eversion method.

Adult↗
PubMed1993

Femoropopliteal and femorotibial greater saphenous vein "in situ" reconstructions in non selected patients. Life table analysis.

594 non selected "in situ" reconstructions were analyzed retrospectively using the life table method. Especially after immediate occlusion the cumulative patency rate is unsatisfactory (33.1% vs 62.3% after 6 years). Patency rates are influenced by the anastomotic site and mainly by run off conditions. The number of patent tibial arteries seems to be the most important determinant. These results prove to be statistically significant.

Aged↗
PubMed1993

[IOP change over time in normal-tension glaucoma].

The authors retrospectively studied intraocular pressure (IOP) changes over time in normal-tension glaucoma (NTG). The materials consisted of 160 eyes of 80 patients who fulfilled the diagnostic criteria for NTG including a continuous daily IOP profile of less than 21 mmHg. They were followed for 12 to 64 months (mean: 31 months) at 1 to 3 month intervals. Eleven eyes (6.9%) in 9 patients (11.3%) showed IOP equal to or greater than 21 mmHg at least once during the follow-up period. The probability of IOP remaining below 21 mmHg for 5 years was 89.1% for each eye and 80.6% for each case according to the Kaplan-Meier life-table method. A discriminant analysis with stepwise variable selection revealed that higher maximum IOP in daily profile, positive history of diabetes mellitus, a family history of glaucoma, male sex, positive history of disc hemorrhage, low diastolic blood pressure, earlier visual field change and concordance in IOP and visual field were significant prognostic factors for subsequent IOP increase.

Adult↗
PubMed2001

Long-term results of cryopreserved arterial allograft reconstruction in infected prosthetic grafts and mycotic aneurysms of the abdominal aorta.

PURPOSE: This prospective, observational study determined the long-term outcome in patients with abdominal aortic infection (primary or prosthetic graft) who were treated with simultaneous aortic/graft excision and cryopreserved arterial allograft reconstruction. METHODS: From April 1992 to March 2000, patients with abdominal aortic infection underwent complete or partial excision of the infected aorta/prosthetic graft and cryopreserved arterial allograft reconstruction. Arterial allografts were harvested from multiple organ donors and cryopreserved at -80 degrees C without rate-controlled freezing. The patients were observed for survival, limb salvage, persistence and/or recurrence of infection, and allograft patency. The results were calculated with life-table methods. RESULTS: During the 8-year study period, 28 consecutive patients (27 men, 1 woman; mean age, 64 years) underwent treatment for abdominal aortic infection (23 graft infections, including 7 graft-enteric fistulas and 5 primary aortic infections). Allograft reconstruction was performed as an emergency procedure in 13 patients (46%). The mean follow-up period was 35.4 months (range, 6-101 months). The overall treatment-related mortality rate was 17.8% (17% for graft infection, 20% for primary aortic infection). The overall 3-year survival was 67%. There was no early or late amputation. There was no persistent or recurrent infection, and none of the patients received long-term (> 3 months) antibiotic therapy. Reoperation for allograft revision, excision, or replacement was necessary in four patients (17%) who were available for examination, with no reoperative perioperative death. The 3-year primary and secondary allograft patency rates were 81% and 96%, respectively. CONCLUSION: Our experience with cryopreserved arterial allograft in the management of abdominal aortic infection suggests that this technique seems to be a useful option for treating one of the most dreaded vascular complications.

Adult↗
PubMed2000

Biologic variables in the outcome of stages I and II neuroblastoma treated with surgery as primary therapy: a children's cancer group study.

PURPOSE: To determine prospectively whether surgery alone is sufficient therapy for Evans stages I and II neuroblastoma and to define biologic and clinical features having prognostic potential for this group. PATIENTS AND METHODS: Between June 1989 and August 1995, 374 eligible children (age range, 0 to 18 years) with newly diagnosed stage I (n = 141) and stage II (n = 233) neuroblastoma were registered onto Children's Cancer Group trial 3881. Surgical resection was the only primary therapy except in cases with spinal cord compression, where radiation therapy was allowed. Event-free survival (EFS) and overall survival (OS) were analyzed by life-table methods according to clinical and biologic features. RESULTS: EFS and OS (mean +/- SE) for all stage I patients were 93% +/- 3.0% and 99% +/- 1.0%, respectively, compared with 81% +/- 4.0% and 98% +/- 2. 0%, respectively, for stage II patients. The significantly higher recurrence rate among stage II patients was managed successfully in 38 of 43 children with either surgery or multimodality treatment. There was one death among stage I patients and six among stage II. For stage II patients tumor MYCN gene amplication, unfavorable histopathology, an age greater than 2 years, and positive lymph nodes predicted a lower OS (P <.05). CONCLUSION: Children with stages I and II neuroblastoma have 98% survival with surgery alone as primary therapy. Supplemental treatment was necessary in only 10% of stage I patients and 20% of stage II patients. In children with localized neuroblastoma, a subset of patients that are at higher risk for death can be defined as those with stage II disease who have tumor MYCN amplification or who are >/= 2 years of age with either unfavorable histopathology or positive lymph nodes.

Adolescent↗
PubMed1999

Axillofemoral bypass operations in Kuopio University Hospital 1985-1996.

BACKGROUND AND AIMS: Axillofemoral bypass has been used since the 1960's in poor-risk patients with aortoiliac atherosclerotic occlusive disease to improve arterial circulation in the lower extremities. This article describes the outcome of 84 consecutive operations in our hospital. MATERIAL AND METHODS: During the period 1.1.1985-31.5.1996, 84 axillofemoral bypass operations were performed in our hospital. In this retrospective study, information was based on patient records and clinical follow-up examination for surviving patients living in the area of Kuopio province and operated before the end of 1995. Patencies and survivals were established using the life table method. RESULTS: The primary patency rate was 81.1 % at one year, 64.3 % at three years and 56.7 % at five years. The secondary patency rates were 92.1%, 67.1% and 57.7 %, respectively. The operative mortality rate was 6.0%. Eighty-five percent of the patients were alive one year after the operation, compared to 50 % after five years. Serious complications were rare, but local wound complications occurred in 29 %. Vascular reoperations were needed in 29 %, particularly thrombectomies. CONCLUSIONS: Axillofemoral bypass gives acceptable results in the treatment of lower leg ischaemia in elderly poor-risk patients.

Adult↗