Premium
Physiological Significance of a Coronary Stenosis Assessed from Pulsatile Resistance Index at Baseline Flow
Author(s) -
Siebes Maria,
Kolyva Christina,
Verhoeff BartJan,
Nolte Froukje,
Spaan Jos A.E.,
Piek Jan J.
Publication year - 2009
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.23.1_supplement.1032.8
Subject(s) - pulsatile flow , cardiology , medicine , stenosis , fractional flow reserve , hemodynamics , aortic pressure , reactive hyperemia , coronary flow reserve , vascular resistance , vasodilation , blood flow , coronary angiography , myocardial infarction
Coronary pressure and flow waveforms change in the presence of a stenosis. We exploited the pulsatile nature of these hemodynamic signals to assess functional coronary stenosis severity. In 29 patients, aortic pressure (Pa), and distal coronary pressure (Pd) and flow velocity (v) were recorded at rest and during maximal hyperemia in a diseased vessel. An index of the dynamic signal energy per cycle was defined as the root mean square of the recorded time‐varying signal after removing the mean. The Pulsatile Velocity Index (PVI) and respective Pulsatile Pressure Indices (PPIa and PPId) were calculated and a stenosis Pulsatile Resistance Index was derived as PRI = (PPId ‐ PPIa)/PVI. Average stenosis resistance SR = (Pa‐Pd)/v and fractional flow reserve (FFR) = Pd/Pa during maximal hyperemia served as gold standards. Hyperemic SR was a major determinant of PPId (p<0.0001), while PVI remained relatively unaffected (r = 0.3). PRI at rest was strongly correlated to both hyperemic SR (p<0.0005) and FFR (p<0.002), with separate relationships for left and right coronary arteries, reflecting different compression of intramural vessels. We conclude that the pulsatile energy of v, Pa and Pd can be utilized to characterize the functional significance of a coronary stenosis without inducing vasodilation. A practical advantage is that PRI is not affected by pressure drift. (Support: NHF grants 2000.090 and 2006B145)