Validity of Global Registry of Acute Coronary Events in Acute Coronary Syndrome Prediction Model for In-hospital Mortality in A Sub-population of Chongqing

Objectives To determine the validity and applicability of the global registry of acute coronary events （GRACE） prediction model for in-hospital mortality in all forms of acute coronary syndrome （ACS） in a sub population of Chongqing. Methods Data of 669 ACS patients were collected retrospectively from Jan 2005 to Apr 2008 and were recorded on a standardized case report form. For each patient the GRACE risk score （ GRACE RS） was calculated （ using the GRACE calculator available from the grace website） using specific variables collected at admission. Patients with missing data and those transferred from other hospitals were excluded. Receiver operating characteristic （ROC） curves were plotted for the GRACE risk score. Results Among 576 ACS patients, 98 （ 17.01% ）, 36 （6.25 % ）, and 442 （76.74 % ） presented with ST-elevation myocardial infarction （ MI）, non-ST elevation MI and unstable angina, respectively. The GRACE risk score could not be determined in 91 （9.3 % ） patients due to missing data or for patients who were transferred from other hospitals and were excluded from the analysis. The median GRACE risk score was 133 （interquartile range： 92 - 174） and, the in-hospital rates of death and death/（re-）MI were 6. 1% and 7. 6 %, respectively. The GRACE risk score demonstrated excellent discrimination （ c-statistic = 0. 86, 95 % CI 0. 79 - 0. 91, P 〈 0. 001 ） for in-hospital death/ （re）-MI. Conclusions The GRACE RS study had a good predictive accuracy for death or MI across the wide range of ACS in this population. It may be a useful risk stratification tool that helps identify high- risk patients who will benefit most from myocardial revascularization and low risk patients who may be spared from undergoing more aggressive interventional treatment.     

The diagnosis and treatment of the no-reflow phenomenon in patients with myocardial infarction undergoing percutaneous coronary intervention

OBJECTIVE

To review the diagnosis and treatment available for myocardial infarction patients having no-reflow in the setting of percutaneous coronary intervention (PCI).

DATA SOURCES

Data for the present review were obtained from searches in PubMed (1997 to 2007) using the following key terms: “acute myocardial infarction”, “no-reflow phenomenon”, “myocardial contrast echocardiography”, “coronary angiography” and “cardioprotection devices”.

STUDY SELECTION

Mainly original articles and critical reviews written by major research pioneers in interventional cardiology were selected.

RESULTS

Despite a fully patent coronary artery post-PCI for myocardial infarction, patients may experience inadequate myocardial perfusion through a given segment of the coronary circulation without angiographic evidence of mechanical vessel obstruction. This phenomenon is defined as no-reflow and is a growing problem in the field of interventional cardiology. Although voluminous clinical trial data are available, the exact mechanisms involved and which treatment should be administered as first-line therapy are currently unknown. The different techniques used to diagnose no-reflow also have their pros and cons; myocardial contrast echocardiography and coronary angiography are the most reliable techniques. In cases when no-reflow was successfully reversed, patient recovery was associated with favourable left ventricular remodelling and increased left ventricular ejection fraction, even in the absence of significant improvement in regional contractile function.

CONCLUSION

Based on the trials in the literature, myocardial contrast echocardiography is the gold standard for the diagnosis of no-reflow. If no-reflow occurs following PCI, treatment with intracoronary adenosine or verapamil should be administered, because this form of therapy is inexpensive and safe, improves flow in the target vessel and may reduce infarct size.     

The use of risk scores for stratification of non-ST elevation acute coronary syndrome patients

OBJECTIVE:

To review the methods available for the risk stratification of non-ST elevation (NSTE) acute coronary syndrome (ACS) patients and to evaluate the use of risk scores for their initial risk assessment.

DATA SOURCES:

The data of the present review were identified by searching PUBMED and other databases (1996 to 2008) using the key terms “risk stratification”, “risk scores”, “NSTEMI”, “UA” and “acute coronary syndrome”.

STUDY SELECTION:

Mainly original articles, guidelines and critical reviews written by major pioneer researchers in this field were selected.

RESULT:

After evaluation of several risk predictors and risk scores, it was found that estimating risk based on clinical characteristics is challenging and imprecise. Risk predictors, whether used alone or in simple binary combination, lacked sufficient precision because they have high specificity but low sensitivity. Risk scores are more accurate at stratifying NSTE ACS patients into low-, intermediate- or high-risk groups. The Global Registry of Acute Cardiac Events risk score was found to have superior predictive accuracy compared with other risk scores in ACS population. Treatments based according to specific clinical and risk grouping show that certain benefits may be predominantly or exclusively restricted to higher risk patients.

CONCLUSION:

Based on the trials in the literature, the Global Registry of Acute Cardiac Events risk score is more advantageous and easier to use than other risk scores. It can categorize a patient’s risk of death and/or ischemic events, which can help tailor therapy to match the intensity of the patient’s NSTE ACS.     

Determination of trihalomethanes produced through the chlorination of water as a function of its humic acid content

Pure humic acid was isolated from Azraq Oasis sediments in the east of Jordan. Different concentrations of humic acid solutions, under different experimental conditions were analyzed for trihalomethanes (THMs), using different concentrations of hypochlorite ion as the chlorinating agent. The analysis of the THMs was done by capillary gas chromatography equipped with a ⁶³Ni-electron capture detector. The presence of trihalomethanes in drinking water from some sites in Jordan was also studied, and some treatment techniques were attempted that could be used for reducing or eliminating trihalomethanes from drinking water.