Pape, Linda

Introduction/Purpose: To examine trends in patient presentation, diagnosis and outcomes of acute aortic dissection over 15 years since the original report from the International Registry of Acute Aortic Dissection (IRAD). Methods: Patient data were collected at 28 international referral centers from 1996 up to the present. Trends were analyzed among 3275 patients divided according to date of enrollment into 6 equal groups and by Type: A (n=2110) or B (n=1165). Results: There was no change over time in the presenting complaints of severe or worst ever pain for Type A and Type B (90% and 96%, respectively), or in the incidence of chest pain ( 80% in Type A and 70% in Type B, respectively), with considerable overlap in chest vs. back pain between types. The report of pulse deficits did not change over time, present in 30% of Type A patients. Normal chest X-ray on presentation increased in Type A acute aortic dissection (AoD) from 13.7% to 31.3% over time (p-value for trend <0.001). In Type B the report of normal chest X-ray increased from 19.9% to 40.9% (p-value for trend <0.001). There were significant trends in initial imaging modalities for Type A: increased use of CT (from 49.4% to 71.6%, p-value for trend <0.001) and decreased use of TEE (from 45.3% to 25.4%, p-value for trend <0.001). For Type B, use of CT increased from 77.2% to 88.4% (p-value for trend .013). A decrease in overall mortality over time was significant for both Type A and Type B patients (see graph). Surgical mortality in Type A patients fell from 25.3% to 16.5% (p-value for trend 0 .003). Conclusions: No significant difference was seen over time in pain severity, chest pain, and presence of pulse deficits. The incidences of a normal chest X-ray, originally thought to be uncommon in dissection cases, increased over time to 30% in Type A and 40% in Type B AoD. Use of CT as the initial imaging modality increased for both Type A and Type B. Lastly, a significant decrease in overall mortality was seen for both Type A and Type B patients.

Background— Studies of aortic aneurysm patients have shown that the risk of rupture increases with aortic size. However, few studies of acute aortic dissection patients and aortic size exist. We used data from our registry of acute aortic dissection patients to better understand the relationship between aortic diameter and type A dissection. Methods and Results— We examined 591 type A dissection patients enrolled in the International Registry of Acute Aortic Dissection between 1996 and 2005 (mean age, 60.8 years). Maximum aortic diameters averaged 5.3 cm; 349 (59%) patients had aortic diameters <5.5 cm and 229 (40%) patients had aortic diameters <5.0 cm. Independent predictors of dissection at smaller diameters (<5.5 cm) included a history of hypertension (odds ratio, 2.17; 95% confidence interval, 1.03 to 4.57; P =0.04), radiating pain (odds ratio, 2.08; 95% confidence interval, 1.08 to 4.0; P =0.03), and increasing age (odds ratio, 1.03; 95% confidence interval, 1.00 to 1.05; P =0.03). Marfan syndrome patients were more likely to dissect at larger diameters (odds ratio, 14.3; 95% confidence interval, 2.7 to 100; P =0.002). Mortality (27% of patients) was not related to aortic size. Conclusions— The majority of patients with acute type A acute aortic dissection present with aortic diameters <5.5 cm and thus do not fall within current guidelines for elective aneurysm surgery. Methods other than size measurement of the ascending aorta are needed to identify patients at risk for dissection.