Given a passage, construct a question on the basis of the information present in the passage. Construct the question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) it answer uses text phrases from the passage. Avoid creating questions that (i) can't be answered correctly without actually understanding the passage and (ii) uses the same words or phrases given in the passage.

Example Input: To evaluate the concordance between thallium-201 uptake and echocardiographic wall thickening, which are both indicators of potentially reversible myocardial dysfunction, in patients with chronic ischaemic left ventricular failure and to assess their relative contribution to predicting improvement in regional function after revascularisation in a subgroup.', '45 patients with chronic ischaemic left ventricular dysfunction (mean (SD) ejection fraction 25 (8)%) underwent echocardiography before and after dobutamine infusion (10 micrograms/kg/min). Of these, 22 patients underwent rest echocardiography at a mean (SD) of 9 (1) weeks after revascularisation. 201Tl imaging was performed during dobutamine echocardiography and at rest, 1, and 4 h after treatment with sublingual glyceryl trinitrate on two separate days. Potentially reversible dysfunction was thought to be present when a myocardial segment contained a Tl score of > or = 3 (ascending score 1-4), or showed improved wall thickening of a dysynergic segment during dobutamine stimulation.', 'Of the 201Tl protocols, the redistribution scan 1 h after treatment with glyceryl trinitrate best demonstrated myocardial viability. Concordance between 201Tl and dobutamine induced wall thickening was 82% (kappa = 0.59) for detecting potentially reversible myocardial dysfunction before revascularisation (n = 45). Regional function improved in 18 of 22 patients after revascularisation. There were 168 dysynergic segments before intervention. The sensitivity of echocardiography and 201Tl imaging for detecting "recoverable" or viable segments after revascularisation was 87% and 92% respectively and specificity was 82% and 78% respectively (P = NS).
Example Output: Do dobutamine echocardiography and thallium-201 imaging predict functional improvement after revascularisation in severe ischaemic left ventricular dysfunction?

Example Input: Various techniques and devices have been proposed for tricuspid valve (TV) repair in patients with tricuspid regurgitation (TR). However, residual or recurrent TR is not uncommon occurring in 20% to 30% of patients. This study reports first experiences with a new three-dimensional annuloplasty ring.', 'We retrospectively reviewed 200 consecutive patients who underwent TV repair for functional TR with the Contour 3D annuloplasty ring (Medtronic, Minneapolis, MN) from December 2010 to February 2013 at our institution. The follow-up is 98% complete (mean 1.0 ±\xa00.7 years; cumulative total 189 patient-years).', 'Mean age was 70.4 ± 9.1 years and the median logistic European system for cardiac operative risk was 7%. Sixty-nine percent of the patients were in New York Heart Association class III/IV. Echocardiography documented moderate or severe TR in 97.5% of the patients, with a mean annulus diameter of 45.1 ± 4.9 mm; 93.5% of the patients underwent a combined procedure, and 20.5% an urgent or emergent operation. The 30-day mortality was 6%. The preoperative TR grade was reduced from 2.45 ± 0.53 to 0.77 ± 0.54 (p < 0.001). At hospital discharge residual II TR or greater was present in 4.3% of the patients. Freedom from recurrent II TR or greater at 2\xa0years was 90.9% ± 4.2% and freedom from TV-related reoperations at 2 years was 98.5% ± 1.0%. No case of\xa0ring dehiscence occurred. Fourteen patients (7%) required a permanent pacemaker implantation for atrioventricular block.
Example Output: Does early experience with a new three-dimensional annuloplasty ring for the treatment of functional tricuspid regurgitation?

Example Input: Icodextrin is a glucose polymer derived by hydrolysis of cornstarch. The different biocompatibility profile of icodextrin-containing peritoneal dialysis (PD) solutions may have a positive influence on peritoneal host defence. Furthermore, cases of sterile peritonitis potentially associated with icodextrin have been reported.', 'The primary objective of this multicentre, longitudinal, observational, non-interventional, prospective cohort study, which included 722 PD patients, was to evaluate the incidence of overall peritonitis in patients treated with icodextrin-containing PD solutions (Extraneal) used during one long-dwell exchange/day compared with those treated with non-icodextrin-containing PD solutions. The secondary objective was to determine if culture-negative peritonitis rates differed between patients treated with icodextrin from two independent manufacturers. All peritonitis episodes were assessed by a Steering Committee in a blind manner.', 'There was no significant difference between icodextrin-treated and control patients in the adjusted overall, culture-positive or culture-negative peritonitis rates. When stratified by the icodextrin supplier, there was no significant difference in the adjusted rate of culture-negative peritonitis episodes between groups.
Example Output:
Does icodextrin impact infectious and culture-negative peritonitis rates in peritoneal dialysis patients : a 2-year multicentre , comparative , prospective cohort study?