Logistic Regression Analysis Of Death Risk Factors For Aortic Dissection

Objective To study the clinical features, examination，therapies of aorticdissection (AD) and to explore the situation of misdiagnosis as well as relatedrisk factors of death， so as to gain more awareness about it and decrease themortality.Methods Retrospectively collected the clinical materials of114AD inpatientsfrom July2003to July2011. Univariate and multivariate Logistic regressionanalysis were used to analysis risk factors.Results (1)114patients were composed of35type I AD(30.7%),8type II(7%)and71type III(62.3%) according to DeBakey typing.(2) The total averageage is52.75±12.22, while52.29±12.19in male and56.58±12.25in female. Theonset age of man is lower than woman(P<0.05).(3) The frequent time of onsetaround the year are the1st,2nd,3rd,10th,11th and12th months.(4) Half ofinpatients were addicted to tobacco before，while63.2%of all patients have increasing blood pressure previously, and hypertension is confirmed in80.7%ofthem.(5) There are62.8%patients suffered from AD without obvious causes,however, sudden pain, especially locating in the thorax, dorsal andabdomen,is the primary symptom in88.6%of all. Abdomen pain is morecommon in type III AD than type I and II AD(P<0.05).(6) Marfan’s syndromeand complications such as myocardial infarction and pericardial effusion weredetected more frequently in type I and II AD than in type III AD. The meanage, frequency of abdomen pain, inpatient BP and renal dysfunction rate arelower in the former than in the latter.(7) ECG abnormalities are found in67%ofthe patients, meanwhile,30%appear Left ventricular hypertrophy with withoutmyocardial strain，15%with T-T changes. In the diagnosis of AD, theconfirmed rates of TTE and X-ray are respectively85.1%and71.7%, and therates of CTA,MRA,DSA are100%.98.2%of patients chose CTA to diagnosis.(8)24.6%of the patients were misdiagnosed as other diseases, the most frequentof which is coronary disease and the secondary is acute abdomen.（9）There are85survivors(74.6%) and29death Cases(25.4%). The mortalities of DeBakeyI,II,III are40.0%,25%,18.3%respectively.（10）Types of AD, surgery orintravascular therapy, hypertension, shock, renal dysfunction and misdiagnosishave significant differences in univariate analysis on death factors(P<0.05).Shock and renal dysfunction is the independent risk factor for death inmultivariate Logistic regression analysis, but surgery and intravascular therapyare the protecting factors. Conclusion AD, which always complicates with hypertension, often happenswith thorax-dorsal pain as the primary symptom in the period of winter andspring. Misdiagnosis rate is rather high because of the complex clinicalmanifestations among different type of AD. Reducing misdiagnosis could helpto abate death. Most patients appear atypical ECG abnormalities. CTA,MRI andDSA all have high diagnosis abilities for AD，among which CTA is the mostcommon and effective one. Shock and renal dysfunction is the independent riskfactor for death,but surgery and intravascular therapy are the protecting factors.