Fractional Flow Reserve in End-Stage Liver Disease.

Area of Science:

• Cardiology
• Hepatology
• Transplantation Medicine

Background:

• Fractional flow reserve (FFR) assesses coronary stenosis severity but relies on assumptions of negligible venous pressure and microvascular resistance.
• These assumptions may be compromised in end-stage liver disease (ESLD) due to fluctuating venous pressure and vasodilation.

Purpose of the Study:

• To evaluate the validity and impact of FFR in patients with ESLD undergoing evaluation for orthotopic liver transplantation.
• To assess the influence of venous pressure (P_v) on FFR measurements and the preserved hyperemic effect of adenosine in this population.

Main Methods:

• Retrospective analysis of 42 patients with ESLD undergoing cardiac catheterization and coronary angiography with FFR.
• Measurements included resting distal coronary pressure (P_d)/aortic pressure (P_a), FFR, P_v, and FFR adjusted for P_v (FFR-P_v).
• Adenosine's hyperemic effect was calculated as resting P_d/P_a - FFR. Primary outcome was 1-year all-cause mortality.

Main Results:

• FFR was measured in 49 stenoses (90% <70% diameter stenosis) in 42 ESLD patients.
• Median FFR was 0.87, median P_v was 8 mm Hg, and median FFR-P_v was 0.86.
• FFR-P_v reclassified only 1 stenosis; venous pressure had minimal impact.
• The hyperemic effect of adenosine was preserved (median 0.06).
• Patients with FFR ≤0.80 had significantly higher 1-year all-cause mortality (73% vs 17%, p=0.001).

Conclusions:

• In ESLD patients evaluated for liver transplantation, FFR remains a reliable indicator of stenosis significance.
• Venous pressure has a minimal impact on FFR values, and the adenosine-induced hyperemic response is preserved.
• FFR ≤0.80 is an independent predictor of 1-year all-cause mortality, even in patients with predominantly angiographically intermediate coronary disease.