Differences in High-susceptible Lesion Location on The Right Coronary Artery and Reverse Flow Between Normotensive and Elevated Systolic Blood Pressure Populations

BACKGROUND: Atherosclerosis is the underlying pathology of coronary artery disease, often promoted by turbulent flow and low shear stress. Recently, acoustic retrograde pressure—linked to the water hammer effect—has emerged as a potential hemodynamic contributor to plaque formation. Our hypothesis is whether there is a statistically significant relationship between acoustic retrograde flow with lesion locations and systolic blood pressure (SBP) level.

METHODS:

30 unstable angina patients without prior Percutaneous Coronary Intervention or Coronary Artery Bypass Graft underwent coronary angiography. A novel dynamic analysis assessed reverse flow and lesion locations in the right coronary artery, comparing findings across SBP groups (120–129, 130–139, and ≥140 mmHg) based on the readings after injecting contrast. For the 120–129 mmHg group, pre-sedation SBP averaging was conducted to more accurately reflect true baseline blood pressure.

RESULTS:

Reverse flow increased with higher SBP. In the unadjusted analysis, reverse flow was seen in 64.3% of patient with SBP <130 mmHg (9/14 patients) and 87.5% with SBP ≥130 mmHg. Adjusted pre-sedation values showed similar trends: 66.7% for SBP <130 mmHg (6/9 patients) and 81% for SBP ≥130 mmHg (17/21 patients)

The lesion site 1R was the most frequent location of reverse flow, particularly at SBP ≥140 mmHg, where it occurred in 90% of patients. Lower SBP was associated with fewer and more variable lesion sites.

CONCLUSIONS:

Reverse arterial flow appears primarily related to lesion location rather than systolic blood pressure levels. However, the small sample size limits the ability to draw firm conclusions.