Given a passage with a context and an answer, 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.
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Question: Context: Hypertrophic cardiomyopathy (HCM) patients are at risk of ventricular arrhythmias (VAs). We aimed to explore whether systolic function by strain echocardiography is related to VAs and to the extent of fibrosis by cardiac magnetic resonance imaging (CMR).', 'We included 150 HCM patients and 50 healthy individuals. VAs were defined as non-sustained and sustained ventricular tachycardia and aborted cardiac arrest. Left ventricular function was assessed by ejection fraction (EF) and by global longitudinal strain (GLS) assessed by speckle tracking echocardiography. Mechanical dispersion was calculated as standard deviation (SD) of time from Q/R on ECG to peak longitudinal strain in 16 left ventricular segments. Late gadolinium enhancement (LGE) was assessed by CMR. HCM patients had similar EF (61 ± 5% vs. 61 ± 8%, P = 0.77), but worse GLS (-15.7 ± 3.6% vs. -21.1 ± 1.9%, P < 0.001) and more pronounced mechanical dispersion (64 ± 22 vs. 36 ± 13 ms, P < 0.001) compared with healthy individuals. VAs were documented in 37 (25%) HCM patients. Patients with VAs had worse GLS (-14.1 ± 3.6% vs. -16.3 ± 3.4%, P < 0.01), more pronounced mechanical dispersion (79 ± 27 vs. 59 ± 16 ms, P < 0.001), and higher %LGE (6.1 ± 7.8% vs. 0.5 ± 1.4%, P < 0.001) than patients without VAs. Mechanical dispersion correlated with %LGE (R = 0.52, P < 0.001) and was independently associated with VAs (OR 1.6, 95% CI 1.1-2.3, P = 0.02) and improved risk stratification for VAs.
Answer: GLS, mechanical dispersion, and LGE were markers of VAs in HCM patients. Mechanical dispersion was a strong independent predictor of VAs and related to the extent of fibrosis. Strain echocardiography may improve risk stratification of VAs in HCM.

Answer: Is strain echocardiography related to fibrosis and ventricular arrhythmias in hypertrophic cardiomyopathy?


Question: Context: The Tonnis radiographic classification of developmental dysplasia of the hip (DDH) has been used as a prognostic indicator for patients with walking-age DDH. The International Hip Dysplasia Institute (IHDI) classification, a new radiographic classification system, has been proposed to be more reliable by its creators. We sought to validate its reliability using independent observers, to compare it to the Tonnis method, and to assess its prognostic significance in a large cohort of patients.', 'A consecutive series of walking-age DDH patients were examined radiographically and classified by the Tonnis and IHDI schemes by 3 independent observers. Interobserver agreement was determined using the Kappa method. Clinical data were collected on patients with regard to success of closed reduction, need for later pelvic osteotomy, and presence of subsequent radiographic avascular necrosis (AVN). The prognostic value of the Tonnis and IHDI classifications to predict these clinical outcomes was determined.', 'A total of 287 hips were available for analysis of the classification schemes. In total, 235 hips underwent attempted closed reduction and were eligible for analysis of successful closed reduction, and 131 hips had >4-year follow-up and were utilized for analysis of late pelvic osteotomy and AVN. Both classifications showed excellent interobserver reliability and in general, there was nonstatistically significant better reliability for the IHDI versus the Tonnis classification. In multivariate analysis, both IHDI and Tonnis classifications were found to be predictive of successful closed reduction and need for late pelvic osteotomy. Both methods showed trends toward being predictive of AVN rate, without statistical significance.
Answer: The IHDI classification is subjectively more facile to use and has excellent interrelater agreement for classifying the radiographic severity of DDH. It is also reliable in predicting success of closed reduction and need for late pelvic osteotomy.

Answer: Is a New Radiographic Classification System for Developmental Hip Dysplasia Reliable and Predictive of Successful Closed Reduction and Late Pelvic Osteotomy?


Question: Context: Circulating tissue factor (TF) has been linked to thrombus propagation. Our group demonstrated that platelets possess mechanisms to capture TF-rich microvesicles (TF-MVs). Serotonin facilitates the development of platelets with increased procoagulant activity. An enhanced platelet serotonin uptake has been identified with increased cardiovascular risk. We have investigated the involvement of serotonergic mechanisms facilitating the interaction of human platelets with TF-MVs. Inhibitory strategies aimed at blocking serotonin and coagulation mechanisms were also studied.', 'Standard aggregometry, flow cytometry, electron microscopy, and thrombin generation assays were performed. TF-MVs induced platelet aggregation in heparinized platelet-rich plasma (PRP) samples; this aggregation was further accelerated by serotonin. In washed platelets, serotonin enhanced platelet aggregation to TF-MVs with a maximum peak of 55.9 +/- 1.8 vs. 48.7 +/- 2.1% (P < 0.05). Inhibitory strategies with a selective serotonin re-uptake inhibitor and with lepirudin decreased these aggregations. Ultrastructural analysis revealed that serotonin induced platelet pseudopodia formation, thus facilitating the engulfment of TF-MVs. In general, serotonin significantly enhanced (P < 0.05) thrombin generation and the expression of activation markers and procoagulant activity in platelets measured for TF-MVs alone.
Answer: Serotonin enhances the interaction of platelets with TF-MVs, increases platelet activation, and potentiates their overall procoagulant activity. The present results could have significant implications in thrombus formation and in the thrombogenic profile of pathological situations with increased cardiovascular risk.

Answer:
Does serotonin enhance platelet procoagulant properties and their activation induced during platelet tissue factor uptake?