Distal dicrotic notch in the coronary artery pressure waveform predicts significant stenosis, as validated by fractional flow reserve, but performs inferiorly as compared to pd/pa
Ahmad MM, Ullah R, Ahmad MN, Ammar Z, Shah S, Riaz A, Kazmi SS, Gupta A, Ammar KA. DISTAL DICROTIC NOTCH IN THE CORONARY ARTERY PRESSURE WAVEFORM PDISTAL DICROTIC NOTCH IN THE CORONARY ARTERY PRESSURE WAVEFORM PREDICTS SIGNIFICANT STENOSIS, AS VALIDATED BY FRACTIONAL FLOW RESERVE, BUT PERFORMS INFERIORLY AS COMPARED TO PD/PA. Journal of The American College of Cardiology. 2016;67(13_S):317-317.
Background: A single small prior study (n=97) has suggested that absence of distal dicrotic notch (DDN) in the coronary artery, distal to an intermediate stenosis, may indicate a significant stenosis, proven by an abnormal fractional flow reserve (FFR). This finding has neither been evaluated by other studies nor compared against other, more established, non hyperemic indices like Pd/Pa (distal coronary pressure/proximal coronary pressure).
Methods: Of the 926 FFR measurements performed in a large tertiary care center over last 4 years, we included 454 measurements with adequate baseline tracing data. After excluding 49 due to absence of aortic dicrotic notch, 405 patients had their tracings printed with pre-adenosine measurement with 8 cardiac cycles and dicrotic notch was characterized visually into four types, i.e., full notch, partial notch, definite change in angle of descending limb at the end of systole, and absent DDN, by two different observers. Operating test characteristics of dicrotic notch were measured against the criterion standard of FFR ≤0.8 to detect significant ischemia.
Results:Out of 405 patients, 43 had absent DDN. The mean FFR in those with absent DDN was significantly lower (0.79 versus 0.86; p=
Conclusions: While an absent DDN is associated with an abnormal FFR, our data suggest meaningfully lower performance in prediction of an abnormal FFR as compared to Pd/Pa, indicating that Pd/Pa should be preferred over DDN in clinical practice.