Cardiology Research, ISSN 1923-2829 print, 1923-2837 online, Open Access
Article copyright, the authors; Journal compilation copyright, Cardiol Res and Elmer Press Inc
Journal website https://www.cardiologyres.org

Original Article

Volume 12, Number 2, April 2021, pages 117-125

Effect of Elevated Left Ventricular End Diastolic Pressure on Instantaneous Wave-Free Ratio and Fractional Flow Reserve Discordance

Figures

Figure 1.
Figure 1. Comparison of iFR/FFR concordance and discordance between normal and elevated LVEDP groups. Significant number of patients in elevated LVEDP group had iFR/FFR discordance. P < 0.05 indicates statistical significance. iFR: instantaneous wave-free ratio; FFR: fractional flow reserve; LVEDP: left ventricular end diastolic pressure.
Figure 2.
Figure 2. Mean LVEDP with range in iFR/FFR concordance and discordance patients. iFR: instantaneous wave-free ratio; FFR: fractional flow reserve; LVEDP: left ventricular end diastolic pressure.
Figure 3.
Figure 3. Frequency distribution of discordant patients according to LVEDP indicating that more than half of patients with iFR/FFR discordance had LVEDP > 25 mm Hg. iFR: instantaneous wave-free ratio; FFR: fractional flow reserve; LVEDP: left ventricular end diastolic pressure.
Figure 4.
Figure 4. Comparison of iFR/FFR concordance and discordance according to stable CAD and acute coronary syndrome. Significantly more patients with acute coronary syndrome had iFR/FFR discordance. P < 0.05 indicates statistical significance. iFR: instantaneous wave-free ratio; FFR: fractional flow reserve; CAD: coronary artery disease.
Figure 5.
Figure 5. Frequency distribution of discordant patients according to iFR. Most of the patients with iFR/FFR discordance had iFR between 0.90 and 0.92. iFR: instantaneous wave-free ratio; FFR: fractional flow reserve.
Figure 6.
Figure 6. Scatter plot graph showing iFR and FFR distribution in patient population. Data below the FFR cutoff of 0.80 indicate discordance. iFR: instantaneous wave-free ratio; FFR: fractional flow reserve; LVEDP: left ventricular end diastolic pressure.

Table

Table 1. Clinical, Angiographic and Hemodynamic Characteristics of Patients
 
CharacteristicsAll (n = 65)Normal LVEDP (n = 30)Elevated LVEDP (n = 35)P value
Variables are expressed as number (%) or mean ± standard deviation. P < 0.05 indicates difference between the groups is statistically significant. PCI: percutaneous coronary intervention; MI: myocardial infarction; CABG: coronary artery bypass graft; UA: unstable angina; NSTEMI: non-ST elevation myocardial infarction; STEMI: ST elevation myocardial infarction; LAD: left anterior descending artery; LCX: left circumflex artery; RCA: right coronary artery; iFR: instantaneous wave-free ratio; FFR: fractional flow reserve; LVEDP: left ventricular end diastolic pressure.
Age (years)66.9 ± 9.467.9 ± 9.566 ± 9.50.42
Sex
  Female18 (28%)9 (30%)9 (26%)0.78
  Male47 (72%)21 (70%)26 (74%)0.78
Medical history
  Diabetes mellitus19 (29%)5 (17%)14 (40%)0.06
  Hypertension54 (83%)23 (77%)31 (88%)0.32
  Hyperlipidemia40 (61%)19 (63%)21 (60%)0.80
  Current smoker9 (14%)4 (13%)5 (14%)0.99
  Chronic systolic heart failure12 (18%)5 (17%)7 (20%)0.76
  Previous PCI18 (28%)6 (20%)12 (34%)0.26
  Previous MI9 (14%)5 (17%)4 (11%)0.72
  Previous CABG5 (7%)2 (6%)3 (8%)0.99
Left ventricular ejection fraction (%)52.5 ± 11.253.95 ± 11.0951.5 ± 11.330.44
Diastolic dysfunction on echocardiogram14 (21%)2 (6%)12 (34%)0.01
GFR < 30 mL/min4 (6%)0 (0%)4 (11%)0.12
Clinical presentation
  Stable angina49 (75%)24 (80%)25 (71%)0.56
  UA/NSTEMI16 (25%)6 (20%)10 (29%)0.56
  STEMI0000.99
Stenosis location
  LAD49 (75%)23 (77%)26 (74%)0.99
  LCX4 (6%)2 (6%)2 (6%)0.99
  RCA10 (15%)5 (17%)5 (14%)0.99
  Diagonal1 (2%)01 (3%)0.99
  Obtuse marginal1 (2%)01 (3%)0.99
Functional assessment
  iFR0.92 ± 0.020.93 ± 0.020.92 ± 0.020.17
  FFR0.84 ± 0.060.85 ± 0.040.82 ± 0.060.07
LVEDP (mm Hg)17.97 ± 7.811.3 ± 3.123.66 ± 5.95< 0.001