Inter-arm and Inter-Leg Systolic Blood Pressure Differences in Aortic Dissection

Background: Inter-arm and inter-leg blood pressure (BP) differences are clues to diagnosis of aortic dissection. Methods: We reviewed 168 aortic dissection cases from January 1999 to September 2005 in a medical center in Taiwan. Thirty-eight cases were suitable for inclusion in our study. Blood pressure of the four limbs were taken on arrival at our emergency department (ED). We used SPSS version 11.5 for statistical analysis of data. Chi-squared test was used for the comparison of inter-limb blood pressure difference on arrival at our ED. Results: There were 30 males and 8 females whose ages ranged from 29 to 91 years, with a mean age of 58.7 ±14 years. Systolic blood pressure on arrival at our ED ranged from 86 to 264 mmHg, with a mean of 175 ±43.3 mmHg. The inter-arm blood pressure difference was 14.5 ±15.7 mmHg, and the inter-leg difference was 12.5 ±14.3 mmHg. The duration of hospital stay was 12.9 ±11.8 days. The group with inter-arm blood pres-sure difference of ≥14.5 mmHg had a lower systolic blood pressure on arrival at the ED than the group with inter-arm BP difference of <14.5 mmHg (164.9 ±46.6 vs. 180.3 ±41.6mm Hg; p = 0.004). The group with inter-leg BP difference of ≥12.5 mmHg had a longer hospital stay than the group with inter-leg BP difference of <12.5 mmHg. (17.5 ±17.5 vs. 10.2 ±5.6 days; p = 0.004). For age and hospital stay, there was no obvious discrepancy between the inter-arm BP difference of ≥14.5 mmHg (p = 0.4) and <14.5 mmHg (p = 0.077). For age and systolic blood pressure on arrival at our ED, there was no significant difference between the inter-leg BP difference of ≥12.5 mmHg (p = 0.28) and <12.5 mmHg (p = 0.113). Conclusion: The group with inter-arm BP difference of ≥14.5 mmHg had a lower systolic blood pressure on arrival at the ED, possibly because of the cardiac output being influenced after dissection. The group with inter-leg BP difference of ≥12.5 mmHg had a longer hospital stay.