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This study aimed to investigate the factors determining early left atrial (LA) reverse remodeling after mitral valve (MV) surgery. The left atrium is frequently dilated in patients with mitral stenosis (MS) or mitral regurgitation (MR). MV surgery usually results in LA volume reduction. However, the factors associated with LA reverse remodeling after MV surgery are not clearly defined. One hundred thirty-eight patients (51 men, 87 women; mean age, 53 years) underwent transthoracic echocardiography before and after MV surgery. Maximal LA volume was measured using the prolate ellipsoid model. The percentage of LA volume change was calculated. The patients were grouped according to age (<50 vs >or=50 years), predominant lesion (pure MR vs some degree of MS), type of surgery (MV repair vs MV replacement), and preoperative rhythm (sinus rhythm vs atrial fibrillation). LA volume decreased from 147+/-93 to 103+/-43 ml (p<0.001) after surgery. LA reverse remodeling was more prominent in patients who were <50 years old (percentage of LA volume change -31.2+/-17.4 vs -18.4+/-19.2, p<0.001), had pure MR (percentage of LA volume change -30.4+/-18.6 vs -17.3+/-18.2, p<0.001), and had a preoperative sinus rhythm (percentage of LA volume change -28.5+/-17.7 vs -20.5+/-20.0, p=0.019). In conclusion, on stepwise multiple regression analysis, preoperative LA volume, predominant lesion, age, and cardiac rhythm were significant predictors of LA reverse remodeling. A larger preoperative LA volume, MR rather than MS, younger age at the time of surgery, and sinus rhythm were important predictors of LA reverse remodeling after MV surgery.  相似文献   
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Purpose  The study investigated the impact of prior abdominal surgery on conversions and outcomes of laparoscopic right colectomy. Methods  A consecutive series of 414 patients with cancer or adenomas who underwent a laparoscopic right colectomy from March 1996 to November 2006 were studied for surgical conversions and outcomes. Conversion was defined as an incision length > 7 cm. Results  Patients with prior abdominal surgery (n = 191) were compared with patients with no prior abdominal surgery (n = 223), and showed no significant differences in age, ASA classification, length of stay, operative time, blood loss, harvested nodes, tumor size, and specimen length. Significantly more wound infections occurred in the prior abdominal surgery group (22 vs.12, P = 0.023). Body mass index > 30 showed a three-fold increased risk of conversion. Fifteen percent of the no prior abdominal surgery patients and 17 percent of the prior abdominal surgery patients were converted (P > 0.05). Conversion was associated with a longer mean length of stay (8.8 days) relative to laparoscopically completed cases (6.3 days) regardless of prior abdominal surgery history (P < 0.0001). Conclusions  Laparoscopic right colectomy for neoplasia was not associated with a higher conversion rate or morbidity in patients with prior abdominal surgery. Prior abdominal surgery is not a contraindication to laparoscopic right colectomy. Presented at the 15th International Congress of the European Association of Endoscopic Surgery, Athens, Greece, July 4 to 7, 2007.  相似文献   
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Objective: Evaluation of the characteristic differences between click-and CE-Chirp-evoked auditory brainstem responses (ABRs) in normal hearing and sensorineural hearing loss. Design: A prospective study. Ears with normal hearing and with sensorineural hearing loss were evaluated. Pure-tone audiometry and click-and CE-Chirp evoked ABRs exams were conducted for all ears. Visual detection levels, wave-V amplitudes, and latencies of the ABRs were assessed. Study sample: Twenty-two ears with normal hearing and 22 ears with sloping type sensorineural hearing loss were examined. Results: In normal-hearing ears, mean amplitudes were larger for CE-chirps than for clicks at all intensities until 80 dB nHL, at which the amplitudes dropped off, presumably due to upward spread of excitation. In ears with sensorineural hearing loss, however the drop-off was less significant at 80 dB nHL. Comparisons with pure-tone audiometry findings revealed ABRs to CE-Chirps to correlate at 0.5, 1, 2, and 3 kHz, and to clicks at 1, 2, 3, and 4 kHz. Conclusions: The CE-Chirp has advantages over clicks for examining normal ears. However, under high-level stimulation, these advantages are no longer present. In ears with sensorineural hearing loss, the upward spread of excitation is less prominent. The CE-Chirps results correlate significantly to low frequency audiometric findings at 0.5 kHz, while clicks do not.  相似文献   
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Purpose of Review

To review recently published diagnostic methods that use high-resolution (HR-) or high-definition- (HD-) anorectal manometry (ARM) techniques.

Recent Findings

The integrated pressurized volume (IPV) is a new measure based on spatiotemporal plots obtained from HR-ARM. The IPV may be clinically useful for improving the prediction of abnormal balloon expulsion test in patients with constipation and for discriminating patients with anorectal disorders from asymptomatic controls. Combination of IPV parameters was superior to conventional manometric parameters in predicting the responsiveness to biofeedback therapy. Moreover, several novel parameters including the HR-ARM resting integral, HR-ARM squeeze profile, and anorectal asymmetry index may each be useful as predictive factors for identifying patients with fecal incontinence.

Summary

HR- and HD-ARM are increasingly performed worldwide for evaluation of anorectal function. Here, we describe new metrics whose clinical significance has not been fully established. Further standardization and validation of these metrics could provide clinically important new information and could help improve our understanding of the pathophysiology of anorectal disorders.
  相似文献   
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