Stratification Index Research Articles

Q wave area for stratification of global left ventricular infarct size

Left ventricular (LV) infarct size is a prognostic determinant after acute myocardial infarction (AMI). ECG data have been used to measure infarct size, but conventional approaches use multiparametric algorithms that have limited clinical applicability. This study tested a novel ECG approach - based solely on Q wave area - for calculation of LV infarct size. Serial 12-lead ECGs were performed in AMI patients. Computerized software was used to quantify Q wave area (summed across surface ECG leads) and Selvester QRS-score components. ECG analysis was compared to the reference of myocardial infarct size quantified by delayed enhancement cardiac magnetic resonance. Overall, 158 patients underwent ECG during early (4±0.4) and follow-up (29±5 days) post-AMI time points. Selvester QRS-score and Q wave area increased stepwise with LV infarct size (P<0.001). Whereas both methods manifested marked increases at a threshold of 10% LV infarction, magnitude was greater for Q wave area (>2.5-fold) than Selvester QRS-score (<two-fold). In receiver operating characteristic analysis, Q wave area (area under the curve=0.83-0.86) and Selvester QRS-score (0.82-0.87) manifested similar performance in relation to a 10% infarct cutoff. When Selvester QRS-score and Q wave area thresholds were selected to optimize sensitivity, both methods yielded similar negative predictive value (Q wave area: 89-91%, Selvester QRS-score: 92-94%) although specificity was higher for Q wave area (44-45 vs. 17-25%; P≤0.01). Q wave area provides an index for stratification of LV infarct size that performs similarly to conventional ECG assessment via the Selvester QRS-score for exclusion of large infarction.

Acoustics Reveals the Presence of a Macrozooplankton Biocline in the Bay of Biscay in Response to Hydrological Conditions and Predator-Prey Relationships

Bifrequency acoustic data, hydrological measurements and satellite data were used to study the vertical distribution of macrozooplankton in the Bay of Biscay in relation to the hydrological conditions and fish distribution during spring 2009. The most noticeable result was the observation of a ‘biocline’ during the day i.e., the interface where zooplankton biomass changes more rapidly with depth than it does in the layers above or below. The biocline separated the surface layer, almost devoid of macrozooplankton, from the macrozooplankton-rich deeper layers. It is a specific vertical feature which ties in with the classic diel vertical migration pattern. Spatiotemporal correlations between macrozooplankton and environmental variables (photic depth, thermohaline vertical structure, stratification index and chlorophyll-a) indicate that no single factor explains the macrozooplankton vertical distribution. Rather a set of factors, the respective influence of which varies from region to region depending on the habitat characteristics and the progress of the spring stratification, jointly influence the distribution. In this context, the macrozooplankton biocline is potentially a biophysical response to the search for a particular depth range where light attenuation, thermohaline vertical structure and stratification conditions together provide a suitable alternative to the need for expending energy in reaching deeper water without the risk of being eaten.

Development of a quality index to evaluate the structure of macroalgal communities

A quality index Ics (= index of community structure) has been developed as a single numeric descriptor to assess the structural state of macroalgal communities and to evaluate their relative development on rocky shores. Coverage of seaweed species were sampled on the field and treated by taxonomic groups, size classes and structural – functional groups (SFG), giving sub-indices It (= taxonomic index), Is (= stratification index) and Io (= organization index), respectively. Six macroalgal communities corresponding to canopies (belts) distributed vertically on the shore have been investigated for several years in 14 sites of Brittany (France). Communities developing at high topographic levels could be distinguished from those occurring at mid-tide to low levels by Ics values. Communities were globally stable over the sampling period, with few geographical discrepancies. Seasonal or sub-community variations could be tracked by sub-index values. The value of Ics to demonstrate the potential evolution of seaweed communities is discussed by comparison to other quality indices and in the perspective of ecological perturbations.

Seasonal effects of thermal stratification on the water quality of deep reservoirs:A case study of Heihe Reservoir, Xi'an City

深水水库作为城市的重要供水水源,通常由于热量在垂向水体上的不均匀分配形成热分层.热分层会阻碍垂向上水体交换引发水质分层现象,在冬季水库发生翻库之后,水体混合导致水库的整体水质下降.结合热分层指数可以客观、直接地表达水库热分层的稳定程度.综合水库的气温、水体更新率和水质参数(溶解氧、pH、总磷、氨氮)的年度变化,对陕西黑河水库2008 2010年的热分层状况进行研究.研究表明:水库的热分层形成会直接恶化底部水质尤其会加速底部水体中溶解氧的消耗;热分层的年度变化主要受气温控制,但在特定时期较大的水体更新率可以在一定程度上弱化水体热分层,减缓底部水质恶化.该结果可使水库管理者在水库分层最稳定、水质恶化最严重时期以人工调节水体更新率的方式弱化热分层,为保证水质安全提供参考.;As a major source of water supply for cities, deep reservoirs usually form thermal stratification due to the uneven vertical heat distribution. Thermal stratification can hinder the vertical water exchange, thus cause water quality stratification. In winter, the water mixing caused by theturnoverof a reservoir leads to the deterioration of overall water quality. With the application of thermal stratification index, the reservoir thermal stratification stability can be objectively and directly expressed. Integrated with the annual changes of reservoir temperature, water renewal rate and water quality parameters (dissolved oxygen, pH, total phosphorous, ammonia nitrogen), this paper studied the thermal stratification conditions of Heihe Reservoir, Shanxi Province, in 2008-2010. Studies showed that the formation of the thermal stratification could directly deteriorate the water quality and particularly accelerate the consumption of dissolved oxygen, in the bottom water. Although annual changes of thermal stratification are mainly controlled by the temperature, at certain periods the higher water renewal rate can weaken the thermal stratification to some extent, and mitigate the deterioration of the bottom water quality. The results show that during the periods of the most stable thermal stratification managers of the most serious deteriorating water quality reservoirs can manually adjust the water renewal rate to weaken the thermal stratification; this is a valuable mechanism in safeguarding the water quality.

Cardiac implantable electronic device infections: Incidence, risk factors, and the effect of the AigisRx antibacterial envelope

Cardiac implantable electronic device (CIED) infection is associated with morbidity and mortality. To determine the incidence and risk factors for CIED infection, to develop a scoring index for risk stratification, and to analyze the effect of the AIGISRx envelope on infection rates. Consecutive patients who underwent a CIED procedure were identified and surveyed for 6 months for the development of an infection necessitating removal of all implanted hardware. In the pre-envelope era, an infection occurred in 25 (1.5%) of 1651 patients. After its availability, an envelope was used in 275 (22%) of 1240 patients; an infection occurred in 8 (0.6%) patients in this era (P = .029 vs pre-envelope). In the overall cohort of 2891 patients, the infection rate was 1.2% and 3.5% in patients with an implantable cardioverter-defibrillator device and those with a cardiac resynchronization therapy defibrillator device, respectively (P = .018); in these patients, 7 independent risk factors predicted infection: early pocket re-exploration, male sex, diabetes, upgrade procedure, heart failure, hypertension, and glomerular filtration rate < 60 mL/min. A composite risk score (0-25; C index 0.72; 95% confidence interval 0.61-0.83) was created by weight, adjusting these 7 factors: 3 groups emerged-low risk (score 0-7; 1% infection), medium risk (score 8-14; 3.4% infection), and high risk (score ≥15; 11.1% infection). The envelope reduced infections by 79% and 100% in the medium- and high-risk groups, respectively. CIED infection most commonly occurred in patients with an implantable cardioverter-defibrillator device and those with a cardiac resynchronization therapy defibrillator device. A composite score based on clinical variables appeared feasible for infection risk stratification. The AIGISRx envelope significantly lowered the risk of CIED infection. Randomized clinical data are warranted.

Prognostic impact of monocyte count at presentation in mantle cell lymphoma - response to Georgeet al

The use of front-line aggressive strategies including autologous stem cell transplantation (ASCT) and the introduction of rituximab represented major advances in the management of mantle cell lymphoma (MCL) and may improve the long-term outcome in these cases (Geisler et al, 2012). However, a large proportion of MCL patients are not young or fit enough to undergo transplantation and often have a short survival. Moreover, the identification of a subset of patients with indolent disease course questioned the need of ASCT upfront for all MCL patients, and highlighted the importance of prognostic indexes for patient risk stratification (Vose, 2012). We recently reported the independent prognostic value of the absolute monocyte count (AMC) at diagnosis in MCL patients in a retrospective study of 97 consecutive cases (Aprile von Hohenstaufen et al, 2013). Our findings were then confirmed in a series of 132 MCL patients from the Mayo Clinic (Porrata et al, 2013). In our series, only a small minority (6%) was treated with ASCT (Aprile von Hohenstaufen et al, 2013), while the Mayo Clinic report included 43 (33%) cases treated with stem cell transplant, but no specific information on the outcome of the transplanted patients was given (Porrata et al, 2013). The letter of George and colleagues, expressly focused on 37 MCL cases treated with rituximab-containing chemotherapy followed by ASCT upfront, may therefore be relevant. They postulate that front-line aggressive immunochemotherapy followed by ASCT may overcome the detrimental effect of the high monocyte count at diagnosis in MCL patients. Indeed, targeting not only the tumour B-cell but also the microenvironment may be critical for effective disease control in MCL, as suggested by the clinical activity of lenalidomide in relapsing patients (Goy et al, 2012). However, the visual difference in the estimated survival curve tails in the analysis reported by Anupkumar et al might suggest that the lack of statistical significant difference between curves in this report could be related to the small sample size (37 patients), and that the study was probably not powered to show any difference. Larger studies are needed to confirm their interesting hypothesis and will also be useful for the definition of the most accurate AMC cut-off value, which is still a controversial issue (Tadmor et al, 2013).

Evaluation Of a Novel 3 Factor Prognostic Score (PS-3) For Patients With Advanced Hodgkin Lymphoma (HL) Treated On US Intergroup E2496

BackgroundThe international prognostic score (IPS) (Hasenclever et al., NEJM 1988) uses 7 factors (age> 45, male sex, hemoglobin<10.5, stage IV, leukocytosis > 15,000, and lymphopenia< 600) to predict a 5 year freedom from progression (FFP) of 42%-84% and overall survival (OS) of 56%-89% for patients with advanced HL. Constructed from a retrospective analysis of patients treated before 1992, the IPS continues to be the most commonly used risk stratification index for advanced HL. Recent studies suggest that the predictive range of the IPS has narrowed due to improved outcomes of patients treated with current therapy (Moccia et al. JCO 2012). In this report we prospectively evaluated the ability of the individual components of the IPS to predict outcome in patients enrolled on the US Intergroup trial E2496. MethodsAll seven IPS (IPS-7) variables were recorded for all patients at study entry. FFP was defined as the time from study entry to disease progression or relapse; deaths that occurred during remission that were not preceded by disease progression/relapse were censored. OS was defined as the time from study entry to death from any cause. Kaplan-Meier methodology was used to construct survival curves. Univariate and multivariate analysis (MVA) was performed using Cox proportional-hazards models. We subsequently constructed an alternative prognostic score utilizing the factors which were significant on MVA (PS-3). ResultsFrom 1996-2006, 854 patients with advanced HL, were randomized to treatment with either ABVD or Stanford V, with no significant differences in outcome (Gordon et al, JCO 2013). While the IPS-7 remained prognostic it did not stratify the lowest risk patients (0-1 risk factor) or patients with 3-5 risk factors, as its predictive range was narrowed due to improved clinical outcomes (Fig 1a and 2a). Table 1 shows the univariate and multivariate analysis for IPS-7 and outcomes. In contrast to the original IPS-7, on MVA, only two factors, hemoglobin and stage were significant for FFP, and three factors for OS: hemoglobin, stage, and age. We then evaluated a new 3 factor score (PS-3) utilizing variables significant on the MVA. The PS-3 was significant for both FFP (p=0.0001) and OS (p<.0001) and clearly separated patients into 4 distinct risk groups with either: 0, 1, 2 or 3 risk factors. The five year FFP was 83%, 74%, 68%, and 63% and OS was 95%, 85%, 75%, and 52% for patients with 0, 1, 2, and 3 risk factors, respectively (Table 2, Fig 1b and 2b). [Display omitted] [Display omitted] Table 15 Year FFP/OS by IPS-7FFPOSUnivariate AnalysisMultivariate AnalysisUnivariate AnalysisMultivariate AnalysisIPS factorNumber of patients (%)HR(95% CI)p-valueHR(95% CI)p-valueHR(95% CI)p-valueHR(95% CI)p-valueAge≥45 years157 (18%)1.3 (0.9-1.8)0.151.2 (0.9-1.8)0.274.0 (2.7-5.9)<0.00013.7 (2.5-5.5)<0.0001Albumin<4g/dl566 (66%)1.0 (0.7-1.4)0.920.8 (0.6-1.1)0.211.6 (1.0-2.5)0.041.3 (0.8-2.1)0.31WBC≥15,000 mm3110 (13%)1.3 (0.9-2.0)0.201.3 (0.8-1.9)0.281.1 (0.7-2.0)0.641.2 (0.7-2.1)0.52Hgb<10.5g/dl145 (17%)1.8 (1.3-2.6)0.00031.7 (1.2-2.5)0.0042.8 (1.9-4.2)<0.00012.1 (1.3-3.3)0.002Lymph count<600 mm3 or<8% of WBC169 (20%)1.3 (1.0-1.9)0.081.2 (0.8-1.7)0.291.2 (0.7-1.9)0.481.0 (0.6-1.6)0.91Male444 (52%)1.1 (0.8-1.5)0.551.1 (0.8-1.5)0.551.1(0.8-1.6)0.571.1 (0.7-1.6)0.68Stage IV206 (24%)1.7 (1.3-2.4)0.00051.5 (1.1-2.1)0.022.3 (1.6-3.4)<0.00011.7(1.1-2.5)0.02Table 25 Year FFP/OS by PS-3PS-3# of patients%5-year FFP5-year OS04745683 ± 295 ± 112753274 ± 385 ± 22821068 ± 575 ± 5323363 ± 1052 ± 10Log rank test p-value0.0001<0.0001 ConclusionIn E2496, for patients with advanced HL, the PS-3 may stratify patients more clearly compared to IPS-7 and provide a simpler model to assess risk. Studies comparing PS-3 with IPS-7, and are ongoing. The incorporation of novel biomarkers and biologic factors into PS-3, as well as validation with other data sets is warranted. Disclosures:No relevant conflicts of interest to declare.

A Multimodel Study of Sea Surface Temperature and Subsurface Density Fingerprints of the Atlantic Meridional Overturning Circulation

AbstractThe Atlantic meridional overturning circulation (AMOC) is an important component of the North Atlantic climate system. Here, simulations from 10 coupled climate models are used to calculate patterns of sea surface temperature (SST) and subsurface density change associated with decadal AMOC variability. The models are evaluated using observational constraints and it is shown that all 10 models suffer from North Atlantic Deep Water transports that are too shallow, although the biases are least severe in the Community Climate System Model, version 4 (CCSM4). In the models that best compare with observations, positive AMOC anomalies are associated with reduced Labrador Sea stratification and increased midocean (800–1800 m) densities in the subpolar gyre. Maximum correlations occur when AMOC anomalies lag Labrador Sea stratification and subsurface density anomalies by 2–6 yr and 0–3 yr, respectively. In all 10 models, North Atlantic warming follows positive AMOC anomalies, but the patterns and magnitudes of SST change are variable. A simple detection and attribution analysis is then used to evaluate the utility of Atlantic midocean density and Labrador Sea stratification indices for detecting changes to the AMOC in the presence of increasing CO2 concentrations. It is shown that trends in midocean density are identifiable (although not attributable) significantly earlier than trends in the AMOC. For this reason, subsurface density observations could be a useful complement to transport observations made at specific latitudes and may help with the more rapid diagnosis of basin-scale changes in the AMOC. Using existing observations, it is not yet possible to detect a robust trend in the AMOC using either midocean densities or transport observations from 26.5°N.

Environmental drivers of small scale spatial variation in the reproductive schedule of a commercially important bivalve mollusc

Understanding variability in reproductive schedules is essential to the management of recruitment limited fisheries such as that of Pecten maximus. Small scale (<5 km) variation in gonad condition and the onset of spawning of P. maximus were found among commercial scallop grounds in Isle of Man waters. Environmental and fishing drivers of these spatial patterns were investigated using a generalised additive model. Rate of change in temperature over the month prior to sampling was identified as the short term driver of gonad weight associated with the autumn spawning event. Long term drivers were average annual chlorophyll a concentration, scallop density, stratification index and shell size. The model explained 42.8% of deviance in gonad weight. Within site variation in gonad condition was high, indicating a “bet hedging” reproductive strategy which may decrease the chance of fertilisation especially at low densities. Therefore, areas protected from fishing, where scallop densities can increase may help buffer against reproductive failure. An increase in shell length from 100 mm to 110 mm equated to an increase of approximately 20% in gonad weight. Protecting scallops from fishing mortality until 110 mm (age four) compared to 100 mm (age three) may lead to an overall increase in lifetime reproductive output by a factor of 3.4.

Saltwater Intrusion Induced by a Complete Neap Tide and Its Effect on Nutrients Variation in the Estuary of Pearl River, China

ABSTRACT Long, A.; Sun, L.; Shi, R.; Zhou, W., and Dang, A.,2013. Saltwater intrusion induced by a complete neap tide and its effect on nutrients variation in the estuary of Pearl River, China. Temporal and spatial variations of water temperature, salinity, dissolved oxygen (DO), and dissolved inorganic nutrients (, , and ) were investigated over a complete neap tide in the estuary of Pearl River, China. Obvious saltwater intrusion was observed at the lower reaches of our survey section: surface water salinity varied from 2.00‰ to 17.80‰, and bottom water salinity varied from 5.59‰ to 22.13‰. The calculated stratification index indicated that the lower reaches had intense stratification during the present neap tide. Obvious dilution of and was observed in the course of saltwater intrusion. Due to intensive decomposition and desorption-releasing action, and concentration increased with increasing water salinity. Investigation results revealed that saltwater intrusion had a significant effect on nutrient st...

Validation of a Risk Stratification Index and Risk Quantification Index for Predicting Patient Outcomes

External validation of published risk stratification models is essential to determine their generalizability. This study evaluates the performance of the Risk Stratification Indices (RSIs) and 30-day mortality Risk Quantification Index (RQI). 108,423 adult hospital admissions with anesthetics were identified (2006-2011). RSIs for mortality and length-of-stay endpoints were calculated using published methodology. 91,128 adult, noncardiac inpatient surgeries were identified with administrative data required for RQI calculation. RSI in-hospital mortality and RQI 30-day mortality Brier scores were 0.308 and 0.017, respectively. RSI discrimination, by area under the receiver operating curves, was excellent at 0.966 (95% CI, 0.963-0.970) for in-hospital mortality, 0.903 (0.896-0.909) for 30-day mortality, 0.866 (0.861-0.870) for 1-yr mortality, and 0.884 (0.882-0.886) for length-of-stay. RSI calibration, however, was poor overall (17% predicted in-hospital mortality vs. 1.5% observed after inclusion of the regression constant) as demonstrated by calibration plots. Removal of self-fulfilling diagnosis and procedure codes (20,001 of 108,423; 20%) yielded similar results. RQIs were calculated for only 62,640 of 91,128 patients (68.7%) due to unmatched procedure codes. Patients with unmatched codes were younger, had higher American Society of Anesthesiologists physical status and 30-day mortality. The area under the receiver operating curve for 30-day mortality RQI was 0.888 (0.879-0.897). The model also demonstrated good calibration. Performance of a restricted index, Procedure Severity Score + American Society of Anesthesiologists physical status, performed as well as the original RQI model (age + American Society of Anesthesiologists + Procedure Severity Score). Although the RSIs demonstrated excellent discrimination, poor calibration limits their generalizability. The 30-day mortality RQI performed well with age providing a limited contribution.

SLN melanoma micrometastasis predictivity of nodal status: a long term retrospective study

BackgroundCompletion lymph node dissection (CLND) is the gold standard treatment for patients with a positive sentinel lymph node (SLN) biopsy. Considering the morbidity associated with CLND it is important to identify histological features of the primary tumor and/or of SLN metastasis that could help to spare from CLND a subset of patients who have a very low risk of non-SLN metastasis. The objective of this study is to identify patients with a very low risk to develop non-SLNs recurrences and to limit unnecessary CLND.MethodsA retrospective long-term study of 80 melanoma patients with positive SLN, undergone CLND, was assessed to define the risk of additional metastasis in the regional nodal basin, on the basis of intranodal distribution of metastatic cells, using the micro-morphometric analysis (Starz classification).ResultsThis study demonstrates that among the demographic and pathologic features of primary melanoma and of SLN only the Starz classification shows prognostic significance for non-SLN status (p<0.0001). This parameter was also significantly associated with disease-free survival rate (p<0.0013).ConclusionThe Starz classification can help to identify, among SLN positive patients, those who can have a real benefit from CLND. From the clinical point of view this easy and reliable method could lead to a significant reduction of unnecessary CLND in association with a substantial decrease in morbidity. The study results indicate that most of S1 subgroup patients might be safely spared from completion lymphatic node dissection. Furthermore, our experience demonstrated that Starz classification of SLN is a safe predictive index for patient stratification and treatment planning.

Impact of Atrioventricular Compliance on Clinical Outcome of Patients Undergoing Successful Percutaneous Balloon Mitral Valvuloplasty

We aimed to assess the impact of atrioventricular compliance (Cn) on the clinical outcome, after successful percutaneous balloon mitral valvuloplasty (PBMV). Using Doppler echocardiography Cn was estimated from the equation that has been previously validated. Mitral valve area (MVA), tricuspid annular plane systolic excursion (TAPSE), pulmonary artery pressure (PAP), and degree of tricuspid regurgitation (TR) severity were evaluated before, immediately, and every 6months with a median duration of 32months after successful PBMV in 150 consecutive patients. An immediate drop in PAP and significant improvement of right ventricle (RV) function was observed after PBMV. Cn was negatively correlated pre and post-PBMV, with the degree of pulmonary artery systolic pressure (PAPs), TAPSE (P<0.0001). Patients with Cn≤3.75mL/mmHg had higher incidence of adverse outcome (developing atrial fibrillation [AF], worsening RV function, progressive left atrial dilation, and redo intervention). Multivariate regression analysis showed that the Cn was the strongest independent predictor of PAPs and RV function before and after successful PBMV (P<0.0001). Cn≤3.75mL/mmHg was the cutoff value for prediction of clinical events at follow-up. Atrioventricular compliance was significantly lower in patients with mitral stenosis (MS) with unfavorable outcome after successful PBMV. The RV function and pulmonary hypertension were significantly correlated with the degree of Cn. This suggests a significant role of Cn in patients with MS, providing a good insight for intervention and utilizing Cn as a noninvasive hemodynamic index for risk stratification and proper timing for intervention in patients with MS.

Impact of Present-on-admission Indicators on Risk-adjusted Hospital Mortality Measurement

Benchmarking performance across hospitals requires proper adjustment for differences in baseline patient and procedural risk. Recently, a Risk Stratification Index was developed from Medicare data, which used all diagnosis and procedure codes associated with each stay, but did not distinguish present-on-admission (POA) diagnoses from hospital-acquired diagnoses. We sought to (1) develop and validate a risk index for in-hospital mortality using only POA diagnoses, principal procedures, and secondary procedures occurring before the date of the principal procedure (POARisk) and (2) compare hospital performance metrics obtained using the POARisk model with those obtained using a similarly derived model which ignored the timing of diagnoses and procedures (AllCodeRisk). We used the 2004-2009 California State Inpatient Database to develop, calibrate, and prospectively test our models (n = 24 million). Elastic net logistic regression was used to estimate the two risk indices. Agreement in hospital performance under the two respective risk models was assessed by comparing observed-to-expected mortality ratios; acceptable agreement was predefined as the AllCodeRisk-based observed-to-expected ratio within ± 20% of the POARisk-based observed-to-expected ratio for more than 95% of hospitals. After recalibration, goodness of fit (i.e., model calibration) within the 2009 data was excellent for both models. C-statistics were 0.958 and 0.981, respectively, for the POARisk and AllCodeRisk models. The AllCodeRisk-based observed-to-expected ratio was within ± 20% of the POARisk-based observed-to-expected ratio for 89% of hospitals, which was slightly lower than the predefined limit of agreement. Consideration of POA coding meaningfully improved hospital performance measurement. The POARisk model should be used for risk adjustment when POA data are available.

The Higher Care At Discharge Index (HCDI): Identifying older patients at risk of requiring a higher level of care at discharge

A screening index, administered at admission, can be useful in identifying older hospitalised patients at risk of requiring a higher level care at discharge. The objective of this study was to describe the development of a risk stratification index for allocating patients into lower and higher risk of requiring higher level care at discharge. A prospective cohort study of general medical patients, aged ≥70 years admitted to three metropolitan acute care hospitals in Brisbane, Australia was conducted. Derivation cohort (n=360) was used to: identify significant predictive factors associated with discharge to a higher level care; and develop a screening index to stratify patients into lower and higher risk. Predictive performance of the index was examined in the validation cohort (n=142). Five independent factors associated with requiring higher level care (identified using stepwise logistic regression analysis) were used to develop the HCDI: no support person to assist with living in the community; received assistance with finances; received assistance with hygiene; short term memory problems; hospitalised in 90 days prior to current hospital admission. Sensitivity, specificity, Positive Predictive Value (PPV) and Negative Predictive Value (NPV) of the dichotomised risk scores of the HCDI were: 76.3%; 73.3%; 36.0%; and 94.0% respectively; correctly classified 73.8%. In the validation cohort, sensitivity was 81.8%; specificity 68.7%; PPV 18.0%; NPV 97.8%, correctly classified 69.7%. Requirement for a higher level care at discharge has important consequences for health service delivery. The HCDI can be used to identify patients at higher risk.

135 CLINICAL APPLICATION AND REPRODUCIBILITY OF CENTRAL PRESSURE AUGMENTATION USING RADIAL ARTERY PULSE WAVE ANALYSIS

BackgroundThe use of surrogate measures for central artery blood pressure (BP) is now commonplace, including radial artery pulse wave analysis (PWA). Prior studies have examined central augmentation index (cAI), defined...

079 THE VENTRICULAR ECTOPIC QS INTERVAL (VEQSI): A POTENTIAL MARKER FOR VENTRICULAR ARRHYTHMIA IN ISCHAEMIC HEART DISEASE

<h3>Introduction</h3> The ventricular ectopic QS interval (VEQSI) has been shown to identify structural heart disease and predict mortality in an unselected population. In ischaemic heart disease (IHD) risk stratification for sudden death is imperfect. We hypothesised that VEQSI would be greater in IHD patients who have suffered serious ventricular arrhythmias. <h3>Methods</h3> 12-Lead Holter recordings from 143 patients with a history of myocardial infarction (MI) were analysed; 38 had prior significant ventricular arrhythmia (66.2±9 years; 92% male); 105 had no history of ventricular arrhythmia (64±11.4 years; 71% male). All ventricular ectopic beats (VEB) were reviewed and VEQSI was measured for each VEB morphology. VEQSI max was recorded as the duration of the broadest VEB. <h3>Results</h3> VEQSI max was significantly longer in patients with a history of prior serious ventricular arrhythmia (214±20 ms and 172±21 ms respectively; p&lt;0.001). Multivariate analysis established VEQSI max as an independent marker for previous life threatening events (OR 1.11; 95% CI 1.07 to 1.16; p&lt;0.001). VEQSI max &gt;195 ms had 86% sensitivity and specificity for distinguishing patients who had suffered significant ventricular arrhythmia (LR 6.39; accuracy 0.86; p&lt;0.001). <h3>Conclusions</h3> VEQSI max &gt;195 ms distinguishes patients with a history of life threatening events from those without prior ventricular arrhythmia. This may be a useful index for risk stratification in IHD. Figure VEQSI max in patients with prior MI but no history of ventricular arrhythmia (MI-no VT/VF cohort) and patients with prior MI and significant ventricular arrhythmia (MI-VT/VF cohort).

Community-acquired pneumonia

Community-acquired pneumonia (CAP) contributes significantly to morbidity and mortality, especially in the elderly. Recent advances aimed at improving outcomes and reducing CAP disease burden are summarized. Emerging data suggests that newer CAP risk stratification indices based on disease severity hold promise in predicting intensive care need. Additional evidence supports a role of procalcitonin and pro-adrenomedullin as biomarkers of disease severity and for guiding antimicrobial therapy. New diagnostic tools have greatly contributed to early diagnosis and better-targeted therapy. There is increasing recognition of the role of coinfections in CAP. In patients with severe disease, therefore, current guidelines advise against monotherapy. Although inclusion of coverage for atypical pathogens in nonsevere CAP has been challenged, evidence suggests that such coverage is beneficial in patients with severe disease. Use of steroids as adjunctive therapy for CAP, however, is associated with complications and prolonged hospitalization. Updated prevention strategies include approval of pneumococcal conjugate vaccine (PCV13) for adults at risk. Despite these developments research aimed at further reducing CAP-related morbidity and mortality is required. Increasing global life expectancy is likely to expand the at-risk population; therefore, research directed at CAP prevention in view of changing demography is essential.

Clinical analysis of gastrointestinal stromal tumor: a report of 539 cases

Objective To investigate the clinicopathological characters of primary gastrointestinal stromal tumor (GIST),and to analyze the influencing factors on the prognosis of patients.Methods The clinical data of 539 patients with primary GIST who were admitted to the Southwest Hospital of Third Military Medical University from January 2002 to December 2012 were retrospectively analyzed.The treatment methods were selected based on the principle of complete resection of tumor without severely influencing the function of related organs,and in combination with the condition of patients and the position of GIST.The method of adjuvant therapy was selected according to the modified National Institite of Health (NIH) risk stratifications.All the patients were followed up till February 2013 via out-patient re-examination,letter or telephone.The survival rate was calculated using the Kaplan-Meier method.The univariate and multivariate analysis of the relationship between clinicopathological factors and the prognosis of GIST patients were done using the Log-rank test and COX regression model,respectively.Results The age of GIST onset was concentrated between 40 and 70 years,which accounted for 76.25％ (411/539).The tumor sites included stomach (316 cases),small intestine (100 cases),esophagus (37 cases),abdomen (37 cases),colon and rectum (26 cases) and pelvic cavity (23 cases).Four hundred and sixty-seven patients received surgical treatment,and 72 received non-surgical treatment.The positive rates of CD117,CD34,α-smooth muscle actin,S-100 were 91.65％ (428/467),86.30％ (403/467),36.18％ (106/293) and 9.78％ (18/184),respectively.A total of 396 patients were followed up with a median time of 29 months (range,2-94 months).The 1-,3-,5-year overall survival rates were 97.4％,78.7％,60.0％.The results of univariate analysis showed that tumor diameter,radical resection,modified NIH risk stratification and mitotic index were correlated with the survival rates of GIST patients (x2=69.846,69.776,67.368,49.041,P ＜ 0.05).The results of multivariate analysis showed that radical resection and modified NIH risk stratification were the independent prognostic factor for patients with GIST (RR =2.493,2.330,P ＜ 0.05).Conclusion Radical resection and modified NIH risk stratification are the independent prognostic factors for patients with GIST,and operation is the main treatment method for GIST. Key words: Gastrointestinal stromal tumor; Surgical procedures, operative; Prognosis

Impact of atrioventricular compliance on clinical outcome of patients undergoing successful percutaneous balloon mitral valvuloplasty

We aimed to assess the impact of atrioventricular compliance (Cn) on the clinical outcome, pulmonary hypertension (PH) and right ventricular (RV) function changes after successful percutaneous balloon mitral valvuloplasty (PBMV). Using Doppler echocardiography Cn was estimated from the equation that has been previously validated. Mitral valve area, tricuspid annular plane systolic excursion (TAPSE), pulmonary artery pressure (PAP) and degree of TR severity were evaluated before, immediately and every 6 months with a median duration of 32 months after successful PBMV in 150 consecutive patients. Compared to control subjects patients with MS had significant lower Cn (P < 0.0001). An immediate drop in PAP and significant improvement of RV function was observed after PBMV. Cn was correlated with the degree of PAPs, TAPSE (P < 0.0001). Patients with Cn < 3.75 mL/mmHg had higher incidence of adverse outcome (developing atrial fibrillation, worsening RV function, progressive left atrial dilation and redo intervention). Multivariate regression analysis showed that the Cn was the strongest independent predictor of PAPs and RV functional before and after successful PBMV (P < 0.0001). Cn < 3.75 mL/mmHg was the cut-of value for prediction of clinical events at follow-up. The change and follow-up in RV function and pulmonary hypertension after successful PBMV were significantly correlated with the degree of Cn. This suggests a significant role of Cn in patients with MS, providing a good insight for intervention and utilizing Cn as a non-invasive hemodynamic index for risk stratification and proper timing for intervention in patients with MS.