OBJECTIVES: This study examined the risk of interference by high magnetic flux density with permanent pacemakers. BACKGROUND: Several forms of electromagnetic energy may interfere with the functions of implanted pacem...OBJECTIVES: This study examined the risk of interference by high magnetic flux density with permanent pacemakers. BACKGROUND: Several forms of electromagnetic energy may interfere with the functions of implanted pacemakers. No clinical study has reported specific and relevant information pertaining to magnetic fields near power lines or electrical appliances. METHODS: A total of 250 consecutive tests were performed in 245 recipients of permanent pacemakers during 12-lead electrocardiographic monitoring. Adedicated exposure system generated a 50-Hz frequency and maximum100-μT flux density, while the electrical field was kept at values on the order of 0.10 V/m. RESULTS: A switch to the asynchronous mode was recorded in three patients with devices programmed in the unipolar sensing configuration. A sustained mode switch was followed by symptomatic pacing inhibition in one patient. No effect on devices programmed in bipolar sensing was observed, except for a single interaction with a specific capture monitoring algorithm. CONCLUSIONS: The overall incidence of interaction by a magnetic field was low in patients tested with a wide variety of conventionally programmed pacemaker models. A magnetic field pulsed at power frequency can cause a mode switch and pacing inhibition in patients with devices programmed in the unipolar sensing configuration. The risk of interference appears negligible in patients with bipolar sensing programming.展开更多
Objectives -The aim of this study was to evaluate the histological characteristics of adenomatous polyps (AP), non adenomatous polyps (NAP), and colorectal cancers (CRC) diagnosed in the greater Paris area. Material a...Objectives -The aim of this study was to evaluate the histological characteristics of adenomatous polyps (AP), non adenomatous polyps (NAP), and colorectal cancers (CRC) diagnosed in the greater Paris area. Material and methods -Pathologists filled out an identification and histological questionnaire for each biopsy or surgical specimen received between 20/09/02 and 20/12/02, which had at least one colorectal polyp or CRC, taken from a patient of the greater Paris area. Results -The participation rate of pathologists was 73.3%and 10 396 patients with 16 681 lesions were included. Lesions consisted in 1 223 CRC among 1 107 patients, 9 280 AP and 6 178 NAP. Mean age of patients with CRC was 68 years, with at least one AP without CRC 62 years, and with at least one NAP without CRC or AP 58 years. The mean number of polyps per patient was 1.4, and increased with age. Average size of AP was larger than that of NAP and the size increased with age for AP but not NAP. pTNM staging of CRC was: pT0, 1%pT1, 4%pT2, 13%pT3, 63%pT4, 19%N0, 55%N1, 24%N2, 19%Nx, 2%. Conclusion -This study provides detailed data on colorectal polyps and colorectal cancers in the greater Paris region, which does not have a cancer registry. Repeated surveys could be helpful for evaluating the efficacy of screening programs in the general population.展开更多
文摘OBJECTIVES: This study examined the risk of interference by high magnetic flux density with permanent pacemakers. BACKGROUND: Several forms of electromagnetic energy may interfere with the functions of implanted pacemakers. No clinical study has reported specific and relevant information pertaining to magnetic fields near power lines or electrical appliances. METHODS: A total of 250 consecutive tests were performed in 245 recipients of permanent pacemakers during 12-lead electrocardiographic monitoring. Adedicated exposure system generated a 50-Hz frequency and maximum100-μT flux density, while the electrical field was kept at values on the order of 0.10 V/m. RESULTS: A switch to the asynchronous mode was recorded in three patients with devices programmed in the unipolar sensing configuration. A sustained mode switch was followed by symptomatic pacing inhibition in one patient. No effect on devices programmed in bipolar sensing was observed, except for a single interaction with a specific capture monitoring algorithm. CONCLUSIONS: The overall incidence of interaction by a magnetic field was low in patients tested with a wide variety of conventionally programmed pacemaker models. A magnetic field pulsed at power frequency can cause a mode switch and pacing inhibition in patients with devices programmed in the unipolar sensing configuration. The risk of interference appears negligible in patients with bipolar sensing programming.
文摘Objectives -The aim of this study was to evaluate the histological characteristics of adenomatous polyps (AP), non adenomatous polyps (NAP), and colorectal cancers (CRC) diagnosed in the greater Paris area. Material and methods -Pathologists filled out an identification and histological questionnaire for each biopsy or surgical specimen received between 20/09/02 and 20/12/02, which had at least one colorectal polyp or CRC, taken from a patient of the greater Paris area. Results -The participation rate of pathologists was 73.3%and 10 396 patients with 16 681 lesions were included. Lesions consisted in 1 223 CRC among 1 107 patients, 9 280 AP and 6 178 NAP. Mean age of patients with CRC was 68 years, with at least one AP without CRC 62 years, and with at least one NAP without CRC or AP 58 years. The mean number of polyps per patient was 1.4, and increased with age. Average size of AP was larger than that of NAP and the size increased with age for AP but not NAP. pTNM staging of CRC was: pT0, 1%pT1, 4%pT2, 13%pT3, 63%pT4, 19%N0, 55%N1, 24%N2, 19%Nx, 2%. Conclusion -This study provides detailed data on colorectal polyps and colorectal cancers in the greater Paris region, which does not have a cancer registry. Repeated surveys could be helpful for evaluating the efficacy of screening programs in the general population.
