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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, BACKGROUND, METHODS, RESULTS. Meshes: Acute Coronary Syndrome, Adenosine, Aorta, Blood Pressure, Cardiac Catheterization, Cohort Studies, Coronary Circulation, Coronary Stenosis, Coronary Vessels, Female, Humans, Hyperemia, Male, Middle Aged, Predictive Value of Tests, ROC Curve, Retrospective Studies, Severity of Illness Index, Vasodilator Agents.
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Does resting Pd/Pa measured with intracoronary pressure wire strongly predict fractional flow reserve? Context: To investigate the relationship between resting distal coronary pressure to aortic pressure ratio (Pd/Pa) and fractional flow reserve (FFR) obtained during maximal hyperemia. FFR is an invasive index of the functional severity of a coronary artery stenosis determined from coronary pressure measurements. It is generally believed that there is little correlation between resting Pd/Pa and FFR obtained during maximal hyperemia. We have therefore studied this relationship in a large cohort of patients who had undergone pressure- wire assessments. 528 consecutive pressure-wire studies performed in 483 patients over a 2-year period were retrospectively analyzed. A linear correlation between resting Pd/Pa and FFR post-pharmacological hyperemia was observed (rho = 0.74; p < 0.0001). When a FFR of < or = 0.75 (or < or = 0.80 as per FAME) was defined as positive, a resting Pd/Pa of < or = 0.85 (< or = 0.87) had a positive predictive value (PPV) of 95% (94.6%), while a resting Pd/Pa of > or = 0.93 (> or = 0.96) had a negative predictive value (NPV) of 95.7% (93%).
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We demonstrate a strong correlation between resting Pd/Pa and FFR. Resting values of Pd/Pa can be used to predict a positive FFR result with relatively high PPV and NPV. This may potentially obviate the need for adenosine infusion in a proportion of pressure-wire studies. Final Decision: yes