Renin Angiotensin System Inhibitors Reduce Aortic Stiffness and Flow Reversal After a Cryptogenic Stroke

Background Blood flow reversal is a possible mechanism for retrograde embolism in the setting of high-risk atherosclerotic plaques in the descending aorta (DAo). Evidence suggests that pulse wave velocity (PWV) is a determinant of blood flow reversal and can be reduced by the destiffening effect of renin-angiotensin system inhibitors (RASI). Purpose To evaluate the impact of antihypertensive therapy on in vivo changes in PWV and flow reversal in patients with cryptogenic stroke. Study Type Prospective. Population Sixteen patients (69 +/- 9 years; 10 males) included after cryptogenic stroke. Field Strength/Sequence 3T.4Dflow sequence (temporal resolution = 19.6 msec) Assessment Patients underwent aortic MRI at baseline and at 6-month follow-up. Patients received standard-of-care antihypertensive therapy that were classified as RASI vs. non-RASI medications (ie, destiffening vs. nondestiffening).We compared aortic PWV, flow reversal fraction (FRF), aortic measurements, cardiac function, and other aortic and cardiac measurements in the antihypertensive therapy groups. Statistical Tests Two-tailed paired or unpaired Student'st-tests (normal distributions) or Wilcoxon tests (nonnormal distribution). Univariate correlations using Pearson correlation coefficients. Results There was a significant decrease in PWV in the RASI (n =10) group (9.4 +/- 1.6 m/s vs. 8.3 +/- 1.9 m/s;P < 0.05), as well as FRF (18.6% +/- 4.1% vs. 16.3% +/- 4.0%;P < 0.05) between baseline and the 6-month MRI studies. There were no changes in PWV or FRF in the non-RASI (n =6) group (P= 0.146 andP= 0.32). A decrease in FRF was significantly correlated with a decrease in PWV (r= 0.53;P < 0.05). Data Conclusion The findings of our study suggest that RASI therapy after cryptogenic stroke resulted in a decrease of blood flow reversal and aortic stiffness. Evidence Level 1 Technical Efficacy Stage 4

Automated summary

The study showed that RASI therapy after cryptogenic stroke can reduce blood flow reversal and aortic stiffness. Compared to the RASI group, there were no significant changes in aortic PWV and FRF in the non-RASI group.