JACC March 6, 2002 ABSTRACTS - Hypertension, Vascular Disease, and Prevention 241A with the blocking antibody to LOX-1 (10 mg/ml) prevented the expression of MMPs (both P<0+01 vs. control) and TIMP2 in response to ox-LDL. In parallel experiments, HCAECs were pretreated with protein kinase C (PKC) inhibitor (Bisindolylmaleimide I, 1 mM) for 30 min and then exposed to ox-LDL. PKC inhibitor blocked the affects of ox-LDL on the expression of MMPs (all P<0.01 vs. ox-LDL group) and TIMP2. Conclusions: These observations indicate that the expression of LOX-1 may affect the stability of atherosclerotic plaques by modulation of MMP1, MMP3 and TIMP2 expres- sion. In this process, the effect of LOX-1 is associated with activation of PKC pathway. POSTER SESSION 1129 Aortic and Peripheral Arterial Disease: Clinical Assessment and Treatment Monday, March 18, 2002, 3:00 p.m.-5:00 p.m. Georgia World Congress Center, Hall G Presentation Hour: 3:00 p.m.-4:00 p.m. 1129-69 Excess Mortality of Type A Aortic Dissection in Women: Impact of Delayed Diagnosis Barbara M, Richartz, Jeanna V. Cooper, Dean E. Smith, Rajendra M+ Mehta, Kim A. Eagle, Christoph A. Nienaber, on Behalf of International Registry of Acute Aortic Dissection (ILIAD), Ann Arbor, Michigan. Background: Acute type A aortic dissection (AAD) is associated with a high mortality and morbidity and delayed diagnosis/treatment leads to excess mortality. The present analy- sis from the International Registry of Acute Aortic Dissection (IRAD) focuses on in+hospi+ tal-mortality and gender differences in relation to the delay in diagnosis/treatment. Methods: 599 patients with AAD were enrolled in the IRAD database. In-hospital-mortal- ity and gender differences were analyzed in relation to the interval between symptom onset and diagnosis (T1), and between established diagnosis and surgical treatment (T2) using Pearson Chi-square test. The intervals T1 and T2 were subdivided in three time frames: A (0 - 4hrs), B (4 - 24hrs), and C (> 24hrs). Results: Of all AAD patients, 34% were female (p < 0.02). Overall, in-hospital-mortality was 34% in female vs 26% in male patients (p < 0.02). A significant delay to diagnosis (T1) was documented in women reflected in a lower percentage of women in the early time frame A ( 24% vs 29%) and intermediate frame B (28% vs 36%), and a high prepon- derance in the late frame C (48% vs 35%),(p < 0.05). With respect to T2 (time to treat- ment) no difference was documented in the preponderance of either sex (T2: A 45% vs 46% men, B 27% vs 31% men, C 29% vs 23% men; ns)+ Conclusions: A significant time delay to diagnosis, but not to the initiation of treatment, cause excess mortality in women. Currently, further analyses are underway to clarify if the delay is due to more atypical symptoms, or other factors that may be intersecting with gender. 1129-70 Clinical Outcomes of Patients Presenting With Aortic Intramural Hematoma Versus Communicating Dissection Affecting the Descending Aorta Monvadi B. SrichaL Michael L. Lieber, Jane M. Kasper, Richard D. White, Cleveland Clinic Foundation, Cleveland, Ohio. Background: Aortic intramural hematoma (IH) is a variant of aortic dissection, distin- guished by absence of both intimal tear and direct flow between true and false lumens, and often thought to be more stable. This study evaluated for differences between out- comes in IH compared with communicating dissection (CD) affecting the descending aorta. Methods: Patients who underwent computed tomography (CT) or magnetic resonance imaging (MRI) for evaluation of acute aortic dissection were identified. IH was confirmed by MRI, and CD was diagnosed by either MRI or CT. Only patients with an acute presen- tation and involvement limited to the descending aorta were included. One-year follow-up data was obtained on each patient. Results: Nineteen patients with IH and 37 patients with CD were identified. Demograph- ics and traditional cardiac risk factors were compared between each group. Hypertension was present in greater than 80% of the patients in both groups. Tobacco use was signifi- cantly higher in CD compared with IH (81% vs 47%, p < 0.05). Although IH patients were generally older (67,4 ± 9.3 vs 61.9 ± 11.5), with more evidence of coronary artery disease (37% vs 13%), these characteristics were not significantly different between each group. IH often had involvement to the diaphragm (63%) or to the renal arteries (RA) (42%), with none extending to the iliacs+ In contrast, CD more often showed extension distal to RA (65%). A higher rate of unfavorable outcomes was seen in IH patients compared to CD patients, though this difference was not statistically significant (58% vs 35%, p=NS). Out- comes in IH consisted of end-organ ischemia in 3 patients (16%) and degradative dilata- tion with saccular outpouchings into the hematoma in 8 patients (42%). In CD, end-organ ischemia occurred in 6 patients (16%), rupture in 4 patients (11%), and progressive aneurysmal dilatation in 3 patients (8%). Conclusions: IH and CD limited to the descending aorta represent two distinct disease entities, with differing clinical characteristics and outcomes, Importantly, IH is not a pre- cursor to CD. 1129-71 Syncope in Aortic Dissection: Diagnostic, Prognostic, and Clinical Implications Brahmaiee K, Nallamothu. Rajendra H. Mehta, Sanjay Saint, Kim A. Eagle, for the IRAD Investigators, University of Michigan, Ann Arbor, Michigan. Background: Syncope is a well-recognized symptom of aortic dissection (AoD), often indicating the development of dangerous complications such as cardiac tamponade (CT). Data describing its clinical implications in AeD are limited. Methods: The International Registry of Acute Aortic Dissection (IRAD) contains consec- utive data on patients with AeD at 18 large referral centers in 6 countries. Data are col- lected via extensive questionnaires recording key clinical findings and OUtCOmes. We used chi-squared tests for bivariate comparisons and multiple logistic regression to assess for predictors of syncope in AoD adjusting for demographics, AoD-type, comor- bidities and complications (eg, CT or stroke). Results: 728 patients with AoD were identified. Syncope was found in 96 (13%) patients; 24 (3%) described it in isolation. Patients with syncope were more likely to suffer in-hos- pital death (34% vs 23%; P=-9,914), CT (28% vs 8%; P<0.001), stroke (18% vs 4%; P<0,091) and other neurologic deficits (25% vs 14%;/==-0,005), After multivariate adjust- ment, clinical factors independently associated with syncope included the presence of type A-AoD, CT and stroke (Table). Conclusion: Patients with type A-AoD or dissection complicated by CT or stroke are more likely to present with syncope. Physicians must be vigilant for these complications when patients suspected of AoD also have syncope and even faster assessments - eg, a quick bedside surface echocardiogram - should be considered to rule-out life-threatening CT. Clinical Factors Associated With Syncope in Patients With Acute Dissection Clinical Factor Odds Ratio 95% CI P-Value Type A Dissection 5.5 2.5-11.8 <0.001 Cardiac Tamponade 3.1 1.7-5.4 <0.001 Stroke 3.5 1.7-7.2 0,001 1129-72 Does Circadian Rhythm Influence the Risk of Acute Aortic Dissection? Raiendra H. Mehta. Roberto Manfredini, Eduardo Bossone, Dean E. Smith, Jeanna V. Cooper, Alfredo LIovet, Toru Suzuki, Christoph A. Nienaber, Kim A+ Eagle, University of Michigan, Ann Arbor, Michigan. Background: Circardian rhythm has been shown to have an impact on the occurrence a variety of cardiovascular events including acute myocardial infarction, sudden cardiac death, and stroke with significant increased in risk of an adverse event on waking up. However, the influence of the sleep-wake cycle on the risk of acute aortic dissection (AAD) is unknown. Methods: In order to evaluate if circadian rhythm influences the risk of AAD, we evalu- ated patients with type A or B AAD (n=673, mean age=62 years, males=70%) enrolled in the International Registry of Acute Aortic Dissection (IRAD) between 1/1996-12_/2000 in whom the time of symptom-onset was recorded. Patients were divided into four groups based on the timing of their symptom-onset: Group A = midnight to 6.00 am, Group B = 6.06 am to noon, Group C = noon to 6.00 pro, and Group D = 6.00 pm to midnight. Results: See figure. ANOVA p < 9.091 among type A, type B, as well as all AAD patients. * = p < 0.001 for pairwise comparison between Group B and other three groups. Conclusions: The risk of AAD is significantly influenced by circadian rhythm with a peak incidence after awakening from sleep during morning hours. Our findings may have sig- nificant implications in terms of prevention and treatment of AAD i.e. the use of antihyper- tensive agents and/or betablockers that maintain effectiveness during the latter part of night and early morning hours in those at risk or with known AAD. { Uo,+'o.pA n Grome a c,,.o,,p c Om=~o 45% 3D4 ~ o s ~ % ~ 40% ZS1 " 3++0 3Pt, , 2~,I * 25% * + , Alldase~o~ T~e Adlss~t~n Type B d~lec~n (n,, 6731 (n -431) (r, • 242) 1129-93 Comparison of Resource Utilization and Discharge Status Between Aortic Stent Grafting and Open Surgical Aneuryam Repair in a Large Community Hospital Gary M. Ansel. Richard J. Snow, Lob Wiseman, Barry S. George, Charles F. Botti, Jr., Mitchell J. Silver, Daniel R. Watson, Geoffrey B. Blossom, MidWest Cardiology Researach Foundation, Columbus, Ohio. Background: We compared the resource utilization and discharge status of patients undergoing abdominal aortic aneurysm (AAA) stent grafting and open surgery for AAA at our community hospital. Method: Database search and chart review for consecutive cases July 1,2000 to May 31,2001. Stent graft (SG) patient population was compared to elective surgical cases for infrarenal AAA treatment. Results: Ninety-nine patient charts were reviewed. Forty-eight elective infrarenal AAA were repaired surgically and 51 by SG during the study period. All AAA were successfully repaired surgically. SG placement was successful in 51/51. At the end of the procedure 17.6% had endoleaks, all type I1. Major complications were more common with surgery