Factors determining the quality of screening colonoscopy: a prospective study on adenoma detection rates, from 12,134 examinations (Berlin colonoscopy project 3, BECOP-3).

BACKGROUND: Screening colonoscopy (SC) outcome quality is best determined by the adenoma detection rate (ADR). The substantial variability in the ADRs between endoscopists may reflect different skills, experience and/or equipment. OBJECTIVE: To analyse the potential factors that may influence ADR variance, including case volume. DESIGN: 12,134 consecutive SCs (mean age 64.5 years, 47% men) from 21 Berlin private-practice colonoscopists were prospectively studied during 18 months. The data were analysed using a two-level mixed linear model to adequately address the characteristics of patients and colonoscopists. The ADR was regressed after considering the following factors: sex, age, bowel cleanliness, NSAID intake, annual SC case volume, lifetime experience, instrument withdrawal times, instrument generations used, and the number of annual continuing medical education (CME) meetings attended by the physician. The case volume was also retrospectively analysed from the 2007 national SC registry data (312,903 colonoscopies and 1004 colonoscopists). RESULTS: The patient factors that correlated with the ADR were sex, age (p<0.001) and low quality of bowel preparation (p=0.005). The factors that were related to the colonoscopists were the number of CME meetings attended (p=0.012) and instrument generation (p=0.001); these factors accounted for approximately 40% of the interphysician variability. Within a narrow range (6-11 min), the withdrawal time was not correlated with the ADR. Annual screening case volume did not correlate with the ADR, and this finding was confirmed by the German registry data. CONCLUSIONS: The outcome quality of screening colonoscopies is mainly influenced by individual colonoscopist factors (ie, CME activities) and instrument quality. CLINICAL TRIAL REGISTRATION NUMBER: Clinical Trial Gov Registration number: NCT00860665.

Left ventricular mass regression following implantation of MIRA bileaflet valves in patients with severe aortic stenosis.

The aim of this study was to evaluate the factors that determine the course of left ventricular mass regression in a homogeneous group of patients following aortic valve replacement by use of the mechanical Edwards MIRA bileaflet prosthesis. Furthermore, we examined if the 19-mm valve leads to an equally good outcome when compared with larger 21- and 23-mm valves. We included 79 patients (49 men) with a mean age of 65+/-9 years operated on for isolated aortic valve replacement with the MIRA valve prosthesis. The analyses included preoperative and postoperative echocardiograms during a follow-up of at least 18 months (995+/-439 days) after valve surgery. Indication for valve replacement was aortic stenosis in 59 and combined disease (aortic stenosis and regurgitation) in 20 patients. Concomitant coronary artery bypass grafting was performed in 28 patients. Left ventricular mass index declined from 155.6+/-47 g/m(2) to 128.8+/-35 g/m(2) (P<0.001) at final visit and normalized in 49% of the patients. Female sex and a preoperatively highly elevated left ventricular mass index were identified as risk factors for residual hypertrophy. However, age and valve size did not have a predictive value for completeness of left ventricular mass regression. This study supports the evidence that an extensive preoperative left ventricular hypertrophy results in an incomplete postoperative mass regression in patients with aortic bileaflet valves. It shows that the slightly elevated pressure gradient in MIRA 19-mm valves does not affect left ventricular mass regression.