The impact of gender on fractional flow reserve measurements (original) (raw)
Related papers
AJP: Heart and Circulatory Physiology, 2006
To evaluate the hemodynamic impact of coronary stenoses, the fractional (FFR) or coronary flow velocity reserve (CFVR) usually are measured. The combined measurement of instantaneous flow velocity and pressure gradient (v-dp relation) is rarely used in humans. We derived from the v-dp relation a new index, dp v50 (pressure gradient at flow velocity of 50 cm/sec) and compared the diagnostic performance of dp v50 , CFVR and FFR. Prior to coronary angiography patients underwent non-invasive stress testing. In all coronary vessels with an intermediate or severe stenosis, the flow velocity, aortic and distal coronary pressure were measured simultaneously with a Doppler and pressure guide wire after induction of hyperemia. After regression analysis of all middiastolic flow velocity and pressure gradient data, the dp v50 was calculated. Using the results of non-invasive stress testing, the dp v50 cut-off value was established at 22.4 mm Hg. In 77 patients, 124 coronary vessels with a mean 39±19% diameter stenosis were analyzed. In 43 stenoses ischemia was detected. We found a sensitivity, specificity and accuracy of 56%, 86% and 76% for CFVR, 77%, 99% and 91% for FFR and 95%, 95% and 95% for dp v50 . To establish that dp v50 is not dependent on maximal hyperemia, dp v50 was recalculated after omission of the highest quartile of flow velocity data, showing a difference of 3%. We found that dp v50 provided the highest sensitivity and accuracy compared to FFR and CFVR in the assessment of coronary stenoses. In contrast to CFVR and FFR assessment of dp v50 is not dependent on maximal hyperemia.
JACC. Cardiovascular interventions, 2017
The study sought to determine the coronary flow characteristics of angiographically intermediate stenoses classified as discordant by fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR). Discordance between FFR and iFR occurs in up to 20% of cases. No comparisons have been reported between the coronary flow characteristics of FFR/iFR discordant and angiographically unobstructed vessels. Baseline and hyperemic coronary flow velocity and coronary flow reserve (CFR) were compared across 5 vessel groups: FFR+/iFR+ (108 vessels, n = 91), FFR-/iFR+ (28 vessels, n = 24), FFR+/iFR- (22 vessels, n = 22), FFR-/iFR- (208 vessels, n = 154), and an unobstructed vessel group (201 vessels, n = 153), in a post hoc analysis of the largest combined pressure and Doppler flow velocity registry (IDEAL [Iberian-Dutch-English] collaborators study). FFR disagreed with iFR in 14% (50 of 366). Baseline flow velocity was similar across all 5 vessel groups, including the unobstructed vessel g...
Current cardiology reviews, 2014
Fractional flow reserve (FFR) is a physiological index of the severity of a stenosis in an epicardial coronary artery, based on the pressure differential across the stenosis. Clinicians are increasingly relying on this method because it is independent of baseline flow, relatively simple, and cost effective. The accurate measurement of FFR is predicated on maximal hyperemia being achieved by pharmacological dilation of the downstream resistance vessels (arterioles). When the stenosis causes FFR to be impaired by > 20%, it is considered to be significant and to justify revascularization. A diminished hyperemic response due to microvascular dysfunction can lead to a false normal FFR value, and a misguided clinical decision.The blunted vasodilation could be the result of defects in the signaling pathways modulated (activated or inhibited) by the drug. This might involve a downregulation or reduced number of vascular receptors, endothelial impairment, or an increased activity of an op...
F ractional flow reserve (FFR) is widely used in clinical practice to assess severity of functional coronary artery stenosis; it is the ratio of distal intracoronary pressure (Pd) to aortic pressure (Pa) measured during pharmacologically induced hyperemia. FFR has been shown to be effective at reducing the rate of stent implantation and improving cardiac outcomes compared with angiographic guidance alone, and its use is supported by international guidelines. 1,2 Large clinical studies such as Fractional Flow Reserve versus Angiography for Multivessel Evaluation (FAME) used conditions of maximal hyperemia achieved by central-line administration of intravenous adenosine to estimate FFR. 3-5 Other landmark studies such as DEFER used both intravenous and intracoronary adenosine, although the frequency of the mode of adenosine administration was not reported. 3 Intravenous adenosine administration is thought to provide the most stable conditions of hyperemia for measurement of FFR. However, even in the best hands, it is possible that Background-We studied the hemodynamic response to intravenous adenosine on calculation of fractional flow reserve (FFR). Intravenous adenosine is widely used to achieve conditions of stable hyperemia for measurement of FFR. However, intravenous adenosine affects both systemic and coronary vascular beds differentially. Methods and Results-A total of 283 patients (310 coronary stenoses) underwent coronary angiography with FFR using intravenous adenosine 140 mcg/kg per minute via a central femoral vein. Offline analysis was performed to calculate aortic (Pa), distal intracoronary (Pd), and reservoir (Pr) pressure at baseline, peak, and stable hyperemia. Seven different hemodynamic patterns were observed according to Pa and Pd change at peak and stable hyperemia. The average time from baseline to stable hyperemia was 68.2±38.5 seconds, when both ΔPa and ΔPd were decreased (ΔPa, −10.2±10.5 mm Hg; ΔPd, −18.2±10.8 mm Hg; P<0.001 for both). The fall in Pa closely correlated with the reduction in peripheral Pr (ΔPr, −12.9±15.7 mm Hg; P<0.001; r=0.9; P<0.001). ΔPa and ΔPd were closely related under conditions of peak (r=0.75; P<0.001) and stable hyperemia (r=0.83; P<0.001). On average, 56% (10.2 mm Hg) of the reduction in Pd was because of fall in Pa. FFR lesion classification changed in 9% using an FFR threshold of ≤0.80 and 5.2% with FFR threshold <0.75 when comparing Pd/Pa at peak and stable hyperemia. Conclusions-Intravenous adenosine results in variable changes in systemic blood pressure, which can lead to alterations in FFR lesion classification. Attention is required to ensure FFR is measured under conditions of stable hyperemia, although the FFR value at this point may be numerically higher.
Coronary flow reserve as a physiologic measure of stenosis severity
Journal of the American College of Cardiology, 1990
PART I: Coronary flow reserve indicates functional stenosis severity, but may be altered by physiologic conditions unrelated to stenosis geometry. To assess the effects of changing physiologic conditions on coronary flow reserve, aortic pressure and heart rate-blood pressure (rate-pressure) product were altered by phenylephrine and nitroprusside in 11 dogs. There was a total of 366 measurements, 26 without and 340 with acute stenoses of the left circumflex artery by a calibrated stenoser, providing percent area stenosis with flow reserve measured by flow meter after the administration of intracoronary adenosine. Absolute coronary flow reserve (maximal flow/rest flow) with no stenosis was 5.9 +/- 1.5 (1 SD) at control study, 7.0 +/- 2.2 after phenylephrine and 4.6 +/- 2.0 after nitroprusside, ranging from 2.0 to 12.1 depending on aortic pressure and rate-pressure product. However, relative coronary flow reserve (maximal flow with stenosis/normal maximal flow without stenosis) was independent of aortic pressure and rate-pressure product. Over the range of aortic pressures and rate-pressure products, the size of 1 SD expressed as a percent of mean absolute coronary flow reserve was +/- 43% without stenosis, and for each category of stenosis severity from 0 to 100% narrowing, it averaged +/- 45% compared with +/- 17% for relative coronary flow reserve. For example, for a 65% stenosis, absolute flow reserve was 5.2 +/- 1.7 (+/- 33% variation), whereas relative flow reserve was 0.9 +/- 0.09 (+/- 10% variation), where 1.0 is normal. Therefore, absolute coronary flow reserve by flow meter was highly variable for fixed stenoses depending on aortic pressure and rate-pressure product, whereas relative flow reserve more accurately and specifically described stenosis severity independent of physiologic conditions. Together, absolute and relative coronary flow reserve provide a more complete description of physiologic stenosis severity than either does alone. PART II: Coronary flow reserve directly measured by a flow meter is altered not only by stenosis, but also by physiologic variables. Stenosis flow reserve is derived from length, percent stenosis, absolute diameters and shape by quantitative coronary arteriography using standardized physiologic conditions. To study the relative merits of absolute coronary flow reserve measured by flow meter and stenosis flow reserve determined by quantitative coronary arteriography for assessing stenosis severity, aortic pressure and rate-pressure product were altered by phenylephrine and nitroprusside in 11 dogs, with 366 stenoses of the left circumflex artery by a calibrated stenoser providing percent area stenosis as described in Part I.(ABSTRACT TRUNCATED AT 400 WORDS)
Circulation, 2013
Background— In chronic ischemic heart disease, focal stenosis, diffuse atherosclerotic narrowings, and microcirculatory dysfunction (MCD) contribute to limit myocardial flow. The prevalence of these ischemic heart disease levels in fractional flow reserve (FFR) interrogated vessels remains largely unknown. Methods and Results— Using intracoronary measurements, 91 coronaries (78 patients) with intermediate stenoses were classified in 4 FFR and coronary flow reserve (CFR) agreement groups, using FFR>0.80 and CFR<2 as cutoffs. Index of microcirculatory resistance (IMR) and atherosclerotic burden (Gensini score) were also assessed. MCD was assumed when IMR≥29.1 (75 th percentile). Fifty-four (59.3%) vessels had normal FFR, from which only 20 (37%) presented both normal CFR and IMR. Among vessels with FFR>0.80, most (63%) presented disturbed hemodynamics: abnormal CFR in 28 (52%) and MCD in 18 (33%). Vessels with FFR>0.80 presented higher IMR [adjusted mean 27.6 (95% confiden...
JACC: Cardiovascular Interventions, 2012
Objectives The aim of this study was to assess the validity of measuring fractional flow reserve (FFR) of the left main (LM) coronary artery in the setting of concomitant left anterior descending (LAD) or left circumflex (LCX) stenoses. Background The theoretical impact of a stenosis in the LAD on the FFR assessment of intermediate LM disease with the pressure wire in an unobstructed LCX is currently unknown. Methods A previously validated in vitro model of the coronary circulation was used to create a fixed intermediate stenosis of the LM and a variable downstream LAD or LCX stenosis. The true LM FFR (FFR LM true), with no concomitant downstream disease, was compared to the apparent LM FFR (FFR LM apparent), with concomitant downstream disease measured with different degrees of LAD or LCX disease. Additionally, an equation based on a resistors model was derived to predict the effect of downstream stenosis on LM FFR (FFR LM predicted). Results In the setting of isolated moderate LM disease (FFR 0.72 Ϯ 0.08), mild to moderate proximal LAD or LCX lesions did not significantly affect LM FFR. Lesions with a composite FFR (LM ϩ downstream disease) Ն0.65 resulted in an FFR LM apparent that was not significantly different from FFR LM true (0.76 Ϯ 0.06 vs. 0.76 Ϯ 0.05, p ϭ 0.124). Our equation for FFR LM predicted accurately modeled the effects of concomitant disease (r ϭ 0.95, p Ͻ 0.001). Conclusions These data suggest that in the presence of proximal mild to moderate LAD or LCX disease, LM FFR can be reliably measured with the pressure wire placed in the uninvolved epicardial artery.
Journal of Pharmacy & Pharmacognosy Research, 2022
Context: The decision to perform an intervention on a narrowed coronary artery depends on the ischemia caused by the stenosis. The indication for intervention usually applies to cases with ≥70% stenosis of vascular diameter because of the risk of myocardial ischemia. Aims: To define the efficacy of fractional flow reserve (FFR) measurement in the evaluation of coronary artery stenosis. Methods: This prospective study was conducted on patients with intermediate coronary artery stenosis who underwent quantitative coronary angiography after coronary computed tomography angiography. Results: The study population consisted of 46 men and 26 women with a mean age of 66.0 ± 12.9 years. FFR was significantly correlated with the grade of angina pectoris (r =-0.387; p<0.01) and showed a negative correlation with percentage diameter stenosis (r =-0.241, p<0.05) and a positive correlation with the minimal lumen diameter (MLD; r = 0.377, p<0.05). The cutoff value to predict positive FFR was >55.62% diameter stenosis and MLD ≤ 1.08 mm. FFR ≤ 0.80 indicating intervention and FFR > 0.80 indicating medical therapy were observed in 56.9% and 43.1% of the cases, respectively. No major cardiac complications occurred during 12 months of follow-up in both groups. Conclusions: FFR measurements for intermediate stenosis of the coronary artery should be used to evaluate the possibility of myocardial ischaemia. If FFR is not available, a cutoff point of >55.62% diameter stenosis or MLD ≤ 1.08 mm can be used to predict the FFR results.