PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Fractional Flow Reserve, Myocardial”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

[Deferral of coronary intervention based on measurement of myocardial fractional flow reserve].

BACKGROUND: Myocardial fractional flow reserve (FFR) is a useful method in assessment of functional significance of coronary stenosis. Deferral of intervention of angiographically intermediate lesion based on FFR measurement is safe in selected patient population as previously described. The aim of the study was to assess mid-term results after deferring coronary intervention of intermediate lesion in a non-selected patient population with no respect to the extent of coronary artery disease and to the results of stress tests if performed. METHODS: A coronary intervention of angiographically intermediate lesion (40 - 70% according to QCA) was deferred in a group of 50 consecutive patients (33 men, mean age 60.8 +/- 10.2 y.) on the basis of FFR > or = 0.75 (mean FFR 0.89 +/- 0.06). FFR was measured in 62 lesions (mean stenosis diameter 55 +/- 7%, left anterior descending 34 lesions, circumflex artery 13 lesions, right coronary artery 15 lesions). One-vessel disease was presented in 14 pts (28%), 36 pts (72%) presented with multivessel disease (two-vessel disease in 27 pts - 54% and three-vessel disease in 9 pts - 18%). Stress test was positive in 15 pts, in 1 pts. negative, and in 3 pts. non-diagnostic. All-cause mortality, cardiac mortality, non-fatal myocardial infarction (MI) and ischemia driven target vessel revascularization (TLR) were recorded during follow-up. Severity of angina pectoris (CCS classification) and a need for antianginal treatment (beta-blockers, nitrates, calcium channel blockers) at the baseline and at the end of clinical follow-up was recorded. RESULTS: Follow-up was completed in 49 patients (98%). Mean time of follow-up is 15.4 +/- 2 months (range 12 - 22 months, median 15 months), two patients died (4 %)--one from colon cancer, the other patient died from lung cancer, there was not any cardiac death recorded, two patients (4%) had target vessel revascularization. Estimated 22 months event-free (all-cause death, MI, TLR) survival was (mean +/- SEM) 86 +/- 7%. There was a significant difference in symptom severity--mean grade of angina pectoris at baseline was 1.8 +/- 1.3, at follow-up 1.1 +/- 1.0 (p < 0.05). There was not difference in use of antianginal drugs was same at baseline and at follow-up (1.7 +/- 0.8 vs. 1.7 +/- 0.7). Thirty-five patients (71%) were treated by statins. CONCLUSIONS: Deferring of coronary interventions of intermediate stenosis based on FFR measurement is safe in a mid-term follow-up. Despite of the same intensity of antianginal treatment there was a significant decrease in symptom severity.

Aged↗

Use of fractional myocardial flow reserve to assess the functional significance of intermediate coronary stenoses.

The goal of the present study was to compare the use of pressure-derived myocardial fractional flow reserve for detecting ischemia with nuclear stress imaging in patients undergoing stent placement for intermediate coronary lesions. We demonstrated that myocardial fractional flow reserve detects ischemia in intermediate coronary lesions accurately when compared with nuclear stress imaging.

Adult↗

Measurement of myocardial fractional flow reserve during coronary angioplasty in patients with old myocardial infarction.

Although myocardial fractional flow reserve (FFRmyo) has been demonstrated to be a useful index for determining functional significance of coronary stenosis, the data in previous studies was derived from a highly selected group of patients. The aim of this study was to investigate the value of FFRmyo in a more clinically relevant group of patients, especially in patients who also had resistance vessel dysfunction. We measured FFRmyo in 20 consecutive patients who had undergone elective coronary angioplasty. FFRmyo was calculated by the ratio of Pc/Pa during intracoronary adenosine 5'-triphosphate (ATP; 50 micrograms in the left coronary and 20 micrograms in the right coronary artery) induced maximal hyperemia, where Pa represents mean aortic pressure obtained by the guiding catheter and Pc represents mean distal coronary pressure measured by a 2.1 F infusion catheter. In total, 21 vessels were dilated and 14 of them were infarct-related arteries. The percent diameter stenosis significantly decreased from 80 +/- 14% to 27 +/- 17%, and the FFRmyo increased significantly from 0.46 +/- 0.18 to 0.77 +/- 0.15 after angioplasty. There was no significant differences in the FFRmyo between vessels with previous myocardial infarction and those without, after angioplasty (0.78 +/- 0.18 vs. 0.76 +/- 0.08). There was a significant correlation between the percent diameter stenosis and FFRmyo before (r = 0.83, P < 0.001) and after (r = 0.64, P < 0.01) angioplasty. In conclusion, FFRmyo significantly improved immediately after angioplasty in vessels with myocardial infarction as well as those without. These results led us to suggest the usefulness of FFRmyo in patients who had both epicardial stenosis and resistance vessel dysfunction. The significant correlation between FFRmyo and quantitative coronary arterial diameter stenosis would further support the more widespread use of FFRmyo in the clinical setting.

Adult↗

Effects of microvascular dysfunction on myocardial fractional flow reserve after percutaneous coronary intervention in patients with acute myocardial infarction.

Fractional flow reserve (FFR) has emerged as a lesion-specific index of the functional severity of coronary stenosis in patients with chronic coronary artery disease. As the coronary blood flow in acute myocardial infarction (AMI) patients with microvascular damage is restricted, the pressure drop across the stenosis during hyperemia may be smaller than expected. However, the effects of microvascular dysfunction on FFR in AMI patients remain undetermined. The study comprised 33 AMI patients who underwent coronary stenting within 12 hr of onset, and 15 patients with stable angina pectoris who underwent elective stenting. Assessment of the 48 lesions by means of intravascular ultrasound and pressure measurements after stenting showed that postinterventional FFR was higher in AMI than angina pectoris patients (0.95 +/- 0.04 vs. 0.90 +/- 0.04; P = 0.002), although there were no significant differences in intravascular ultrasound parameters. AMI patients were divided into two subgroups based on their postprocedural Thrombolysis on Myocardial Infarction (TIMI) flow grade (23 patients with TIMI 3 and 10 with TIMI 2). There were no differences in intravascular ultrasound parameters between the AMI subgroups, while FFR was greater in the patients with TIMI 2 than in those with TIMI 3 (0.98 +/- 0.02 vs. 0.93 +/- 0.05; P = 0.017). No significant correlation was found between FFR and intravascular ultrasound parameters in either AMI subgroup, while FFR of more than 0.94 was observed in all TIMI 2 cases independent of residual stenosis severity. We conclude that in patients with marked microvascular dysfunction, FFR may not be reliable for the assessment of coronary lesion severity and may underestimate coronary lesion severity.

Aged↗

Relation between myocardial fractional flow reserve calculated from coronary pressure measurements and exercise-induced myocardial ischemia.

BACKGROUND: Myocardial fractional flow reserve (FFRmyo) is a functional index of stenosis severity that can be derived from intracoronary pressure measurements performed during maximal vasodilatation. It is defined as the maximal myocardial perfusion during hyperemia in the presence of a stenosis in the epicardial artery expressed as a fraction of its normal maximal expected value. To determine threshold values of FFRmyo, of hyperemic translesional pressure gradient (delta P(max)), and of resting translesional pressure gradient (delta P(rest)) that are uniformly associated with exercise-induced ischemia, we studied the relation between these pressure-derived indexes and the results of exercise ECG. METHODS AND RESULTS: We studied 60 patients with an isolated lesion in one major epicardial coronary artery, normal left ventricular function, and no left ventricular hypertrophy. Maximal exercise ECG (off anti-ischemic medication) was performed within 6 hours before catheterization. Intracoronary pressure measurements were taken at rest and during hyperemia with a pressure monitoring guide wire. ST-segment depressions at peak exercise (considered abnormal when > or = 0.1 mV) were compared with FFRmyo, delta P(max), and delta P(rest). Thirty-seven patients had an abnormal and 23 patients a normal exercise ECG. A significant linear correlation was found between the magnitude of ST-segment depressions and both FFRmyo and delta P(max) (r = -.75, SEE = 0.53; r = .71, SEE = 0.56). A weaker correlation was noted between ST-segment depressions and delta P(rest) (r = .53, SEE = 0.67). Sensitivity and specificity curves were constructed for the prediction of an abnormal exercise ECG for the three pressure-derived indexes. The values that most accurately predicted an abnormal exercise ECG were 66% for FFRmyo, 31 mm Hg for delta P(max), and 12 mm Hg for delta P(rest). No patient with a FFRmyo value > 72% showed an abnormal exercise ECG. In addition, receiver operating characteristic curves demonstrated a greater accuracy of FFRmyo and of delta P(max) than of delta P(rest) for predicting the results of the exercise ECG. CONCLUSIONS: In the present study, cutoff values of FFRmyo and translesional pressure gradients are established from the relation between intracoronary pressure-derived indexes and ECG signs of myocardial ischemia during maximal exercise. These values can be helpful for clinical decision making in cases with dubious angiographic results. Furthermore, our data support the concept that stenosis physiology is better reflected by hyperemic than by basal measurements.

Adult↗

The relationship between corrected TIMI frame count and myocardial fractional flow reserve.

UNLABELLED: Thrombolysis in myocardial infarction (TIMI) frame count (TFC) is a reproducible, objective and quantitative index of coronary flow that allows standardization of TIMI flow grades. After myocardial infarction (MI), hyperemic and basal flows decrease in the infarct region due to residual stenosis and increased resistance in the microvasculature subtended by this infarct-related artery (IRA). Myocardial fractional flow reserve (FFRmyo) is a lesion-specific index for epicardial stenosis. FFRmyo can also be used as a criterion for assessing the success of revascularization therapy. The aim of this study was to investigate the relationship between improvement of the corrected TFC (CTFC) and change in FFRmyo, which were determined in the IRA in patients with recent MI who underwent mechanical revascularization. METHODS: Forty-one patients (28 male; age, 58.3 +/- 12.3 years) early after MI with > 60% narrowing in the IRA who underwent stent implantation for this residual stenosis were included in this study. After angiography, a fiber-optic pressure monitoring guidewire was positioned distal to the stenosis to be dilated. Means of aortic (Pa) and distal (Pd) pressures were recorded simultaneously under baseline and hyperemic conditions. FFRmyo (Pd/Pa) was determined under adenosine hyperemia before and after stent implantation, as was TFC. Percentage of the improvement in the CTFC and FFRmyo was calculated for each lesion. The first frame used for TFC was defined by a column of contrast extending across > 70% of the arterial lumen and last frame counted was that in which contrast first appeared in the distal, pre-defined landmark branches for each vessel. CTFC was calculated for the LAD by dividing TFC of the LAD by a factor of 1.7. RESULTS: Eighteen patients had LAD, 10 had CX and 13 had RCA lesions. After stent implantation, the CTFC improved by 41% (from 32.3 +/- 3.4 to 19.2 +/- 2.1; p < 0.0001) and FFRmyo improved by 69% (from 0.53 +/- 0.11 to 0.90 +/- 0.15; p < 0.0001). There was a statistically significant correlation between the change in FFRmyo and improvement in the TFC (r = 0.85). CONCLUSION: Improvement in CTFC is associated with change in FFRmyo in the IRA undergoing mechanical revascularization. After mechanical revascularization, CTFC decreases proportionally to improvement of the FFRmyo. These two parameters support each other in terms of successful revascularization and this relationship shows the recruitability of CTFC in terms of FFRmyo as well.

Blood Flow Velocity↗

Dobutamine-induced wall motion abnormalities: correlations with myocardial fractional flow reserve and quantitative coronary angiography.

OBJECTIVES: This study evaluated both the relation between dobutamine-induced wall motion abnormalities and the physiologic and morphologic features of epicardial coronary artery stenoses and the impact of the extent of the area at risk on the sensitivity of dobutamine echocardiography. BACKGROUND: The accuracy of dobutamine echocardiography has traditionally been assessed by comparing results with stenosis geometry. Myocardial fractional flow reserve is a functional index of coronary stenosis severity that takes into account both antero-grade and collateral flow and may therefore be a more appropriate standard for comparison. METHODS: Seventy-five patients with normal left ventricular function, good echocardiographic images and an isolated coronary stenosis underwent, within 6 h, dobutamine echocardiography, quantitative coronary angiography and intracoronary pressure measurements. Myocardial fractional flow reserve was calculated as the ratio of mean hyperemic distal coronary to aortic pressure. RESULTS: The degree of dobutamine-induced dyssynergy correlated significantly with percent diameter stenosis (r = 0.68), area stenosis (r = 0.68) and minimal lumen diameter (r = -0.60) and markedly better with myocardial fractional flow reserve (r = -0.77). However, marked dispersion of the individual data was observed. The sensitivity of dobutamine echocardiography in detecting lesions with a minimal lumen diameter < or = 1 mm and diameter stenosis > or = 50% was 83% and 80%, respectively. All but one patient with a myocardial fractional flow reserve >0.75 had a normal stress test result. Among patients with a myocardial fractional flow reserve < or = 0.75, the sensitivity of dobutamine echocardiography was significantly lower for lesions in vessels with a reference diameter < or = 2.6 mm than for lesions in larger vessels (58% vs. 90%, p = 0.008). CONCLUSIONS: 1) The magnitude of wall motion abnormalities induced by dobutamine infusion correlates with angiographic and, more closely, with functional indexes of stenosis severity, even though a wide scatter is observed. 2) In patients with a functionally significant stenosis, the amount of myocardium at risk is a critical determinant of the accuracy of dobutamine echocardiography.

Coronary Angiography↗

Mismatch between results of myocardial fractional flow reserve (FFR) measurements and myocardial perfusion SPECT for identification of the severity of ischemia: pitfall of FFR in patients with prior myocardial infarction.

We experienced two rare cases of mismatch between the results of FFR and myocardial perfusion SPECT for identification of myocardial ischemia after myocardial infarction. If a FFR cutoff value of 0.75 is applied as in angina patients to patients with myocardial infarction, the severity of ischemia may be underestimated.

Aged↗

Reliability of pressure-derived myocardial fractional flow reserve in assessing coronary artery stenosis in patients with previous myocardial infarction.

In 167 patients with suspected coronary artery disease, 74 of whom had myocardial infarction (MI), measurement of myocardial fractional flow reserve (FFR) in previous infarction territories, using a cut-off point of 0.75, showed a sensitivity of 79% and a specificity of 79% for myocardial ischemia as demonstrated by thallium-201 myocardial imaging. This sensitivity and specificity were similar to a sensitivity of 79% and a specificity of 72% observed in territories not related to MI. In addition, a receiver-operating characteristic curve analysis revealed that the best predictability of FFR for myocardial ischemia was between 0.74 and 0.76, regardless of the presence or absence of MI.

Aged↗

Discrepancy between morphologic and functional criteria of optimal stent deployment using intravascular ultrasound and pressure derived myocardial fractional flow reserve.

BACKGROUND: Pressure derived myocardial FFR, a functional index of epicardial stenosis has been proposed for the assessment of optimal stent deployment. The following study evaluated the potential of serial fractional flow reserve (FFR) measurements in comparison to the 'gold standard' intravascular ultrasound (IVUS) for optimal stent deployment and its long-term outcome. METHODS: 35 patients with a single de novo lesion underwent PTCA followed by stent implantation with an initial inflation pressure of 12 atm. If optimal stent expansion using IVUS-criteria were not fulfilled, re-dilatation at 16 atm as well as additional inflations with larger balloon sizes were performed to reach the procedural end-point. IVUS and FFR were performed after each dilatation (n = 136). Angiography was repeated after 6 months. RESULTS: In 30 pts who fulfilled IVUS criteria, mean lumen area (2.9+/-1.3 mm2) increased after PTCA and stent implantation to 10.0+/-3.0 mm2. In six pts, optimum stent deployment according to a value of FFR0.94 was not reached. Four of six pts reached the IVUS criteria at 12 atm and two pts at 16 atm, respectively. Positive and negative predictive values of FFR were 26 and 64%. Three of the 30 pts (10%) revealed a restenosis at three months follow-up. One of these restenosis was seen in a patient with a post-procedural FFR<0.94. CONCLUSIONS: FFR was not valid to predict optimal stent expansion according to IVUS criteria but could delineate under-expanded stents despite a reasonable angiographic appearance. Morphologic (IVUS) and functional criteria (FFR) for optimal stent deployment revealed a comparably low restenosis rate.

Aged↗

Measurement of myocardial fractional flow reserve during coronary angioplasty in infarct-related and non-infarct related coronary artery lesions.

Myocardial fractional flow reserve (FFRmyo) has been demonstrated to be a useful method for determining the physiologic importance of a given coronary lesion. However, the reliability of the FFRmyo measurement is unknown in infarct-related arteries (IRA). The aim of this study was to measure and correlate the FFRmyo results of 14 consecutive patients who had recent acute myocardial infarction (AMI) (Group 1) with 14 consecutive patients who didnOt have AMI (Group 2) before and after percutaneous transluminal coronary angioplasty (PTCA). Quantitative coronary angiography (QCA) and FFRmyo measurements were determined both before and after optimal PTCA for all patients. FFRmyo was measured by use of a 0.014 inch guidewire as the ratio of the pressure distal to the target lesion to the aortic pressure taken during the maximal hyperemia induced by intracoronary adenosine. There were no differences between the two groups related to gender, target artery reference diameter, minimal luminal diameter and percent diameter stenosis of the vessel both before and after PTCA. While FFRmyo results after PTCA were not different between the groups, they were statistically different before PTCA (Group 1: 77.6+/-5.4%, Group 2: 63.3+/-8.4%; p<0.001). Although QCA-determined percent diameter stenosis revealed a significant degree of stenosis (66.5+/-10.5%) for Group 1, FFRmyo values were higher than 75% (77.6+/-5.4%), indicating insignificant stenosis. Thus, it was concluded that FFRmyo measurements before PTCA were significantly different between IRA and non-IRA and that the method may not be valid for the determination of stenosis significance in IRA.

Aged↗

Comparison of myocardial fractional flow reserve and intravascular ultrasound for the assessment of slotted-tube stents.

Intravascular ultrasound (IVUS) and myocardial fractional flow reserve (FFR) have been reported to provide similar results for assessment of coil stent deployment. Their relative value in slotted-tube stents has not been investigated. Fourteen patients subjected to coronary angioplasty and IVUS-guided elective stenting with a slotted-tube stent underwent IVUS assessment and FFR measurement following stent implantation at inflation pressures of 12 and 18 atm. FFR values (mean +/- SD) preangioplasty, postangioplasty, and poststenting at 12 atm and 18 atm, were 0.58 +/- 0.07, 0.83 +/- 0.05, 0.94 +/- 0.02, and 0.94 +/- 0.02, respectively. After inflation at 12 atm, the area under the receiver operating characteristic (ROC) curve for the concordance of IVUS and FFR measurements was 0.89 (P = 0.02). Six patients had either an abnormal IVUS (n = 2) or FFR < 0.94 (n = 1) or both abnormal IVUS and FFR < 0.94 (n = 3) after the first inflation and had a second inflation at 18 atm. The area under the ROC curve for the concordance between IVUS and FFR final measurements was 0.855 (P = 0.10). Perfect concordance between IVUS and FFR was seen only for FFR values less than 0.91 or larger than 0.94. Overall, IVUS and FFR have substantial concordance with respect to slotted-tube stent deployment. However, FFR values between 0.91 and 0.94 after inflation are difficult to interpret.

Aged↗

Medium-term follow-up of intermediate coronary stenoses left unrevascularized based on myocardial fractional flow reserve findings.

OBJECTIVE: Coronary stenoses of intermediate severity create difficulties in decision making when revascularization is concerned. Myocardial fractional flow reserve (mFFR), an accurate tool to identify physiological significance of individual coronary stenoses, may help solve this problem. METHODS AND RESULTS: Fifty-eight intermediate (30-70%) coronary stenoses in 51 patients (mean age 54.4 +/- 8.9 years, 9 women) were left unrevascularized because of normal (> or = 0.75) mFFR findings and the patients were prospectively followed with regard to the occurrence of death, myocardial infarction and target vessel revascularization. The mean reference vessel diameter, percent stenosis and mFFR of the intermediate lesions were 3.3 +/- 0.3 mm, 46.8 +/- 9.2% and 0.86 +/- 0.05, respectively. Of the 58 intermediate lesions, 20 (34%) were associated with perfusion defects on thallium scan. Significant (> 70%) disease in addition to the one with the intermediate stenosis was present in I coronary artery in 24 (47%), and 2 coronary arteries in 6 (12%) patients and angioplasty of at least one significant stenosis was performed at the initial evaluation in 18 (35%) patients. Follow-up for a mean of 16.6 +/- 6.6 months disclosed no death or myocardial infarction. Target vessel revascularization was performed in 3 (6%) patients at a mean of 4 +/- 2.6 months. A control angiogram, which was performed in 12 of 18 patients who had undergone angioplasty at the initial evaluation revealed restenosis in 3 (25%) patients with no significant angiographic changes in the target intermediate stenoses. Anginal status was found to be significantly improved at follow-up. CONCLUSIONS: In this study, we found that intermediate coronary stenoses with an mFFR > or = 0.75 have a favourable medium-term clinical outcome with respect to major cardiac adverse events when left unrevascularized based on mFFR findings.

Adrenergic beta-Antagonists↗

Does coronary stenting following balloon angioplasty improve myocardial fractional flow reserve?

PURPOSE: Suboptimal distal coronary flow reserve after successful balloon angioplasty has been attributed to angiographically unrecognized inadequate lumen expansion, and adjunct coronary stenting has been shown to improve coronary flow reserve. The aim of this study was to investigate whether myocardial fractional flow reserve (FFRmyo) would increase further after coronary stenting compared with balloon angioplasty alone in the same patient group. METHODS: FFRmyo and quantitative coronary angiography were obtained before and after pre-stent balloon dilation, and again after stent placement in 11 patients (7 left anterior descending artery, 3 right coronary artery and 1 left circumflex artery). FFRmyo was calculated as the ratio of Pd/Pa during intracoronary adenosine 5'-triphosphate (50 micrograms and 20 micrograms in the left and right coronary arteries, respectively)-induced maximum hyperemia, where Pd represents mean distal coronary pressure measured by a 2.1 Fr infusion catheter and Pa represents mean aortic pressure measured by the guiding catheter. RESULTS: Percent diameter stenosis significantly decreased after balloon angioplasty (74% +/- 15% vs 37% +/- 17%, p < 0.001), and decreased further after stent placement (18% +/- 10%, p < 0.001 vs baseline and balloon angioplasty). FFRmyo after coronary stenting (0.85 +/- 0.09) was significantly higher than that at baseline (0.51 +/- 0.16, p < 0.001) and after balloon angioplasty (0.77 +/- 0.11, p < 0.05). There was a significant correlation between angiographic variables and FFRmyo. The increase in lumen dimensions after coronary stenting was followed by a further significant improvement of FFRmyo. CONCLUSION: These results suggest that coronary stenting may provide a more favorable functional status and lumen geometry of residual coronary stenosis compared with balloon angioplasty alone.

Adult↗

Long-term follow-up after deferral of coronary intervention based on myocardial fractional flow reserve measurement.

OBJECTIVE: To assess long-term results after deferring coronary intervention (percutaneous coronary intervention (PCI)) of an intermediate lesion with a value of myocardial fractional flow reserve (FFR) > or = 0.75 in a 'real life' patient population with no respect to results of stress tests (if performed) or coronary disease extent. METHODS: PCI of an intermediate lesion was deferred in a group of 85 consecutive patients (54 men, 61+/-10 years) on the basis of the result of FFR > or = 0.75 (mean FFR, 0.89+/-0.06%). FFR was measured in 111 stenoses (mean diameter stenosis, 54+/-8%, left anterior descending coronary artery, 65 (58%), left circumflex coronary artery, 24 (22%), right coronary artery, 22 (20%). Multi-vessel disease (defined as visually assessed diameter reduction of more than 50% in at least two arteries of more than 1.5 mm diameter, supplying at least two of the three major coronary artery perfusion territories) was present in 67% of patients (one-vessel disease, 28 patients (33%), two-vessel disease, 39 patients (46%), three-vessel disease, 18 patients (21%). Recorded events during follow-up were as follows: all-cause death, cardiac death, non-fatal myocardial infarction, ischemia-driven target lesion transcatheter revascularization (TLR) and coronary artery bypass graft (CABG). Angina class (Canadian Cardiovascular Society (CCS) classification) and the need for anti-anginal drugs were recorded. RESULTS: Follow-up was completed in 85 patients (100%). Mean duration of follow-up was 22.6+/-6.6 months (range 4-33 months). Events occurred in 11 patients (13%). Seven patients died; this included two cardiac deaths. A non-fatal myocardial infarction occurred in one patient, one patient needed TLR and three patients underwent CABG. Estimated 33 month cardiac-event-free survival (Kaplan-Meier) was 91+/-4%. Angina class decreased [1.6+/-1.2 compared with 0.8+/-0.8 (P < 0.0001)] without difference with respect to the use of anti-anginal drugs (1.7+/-0.8 compared with 1.7+/-0.9, P = NS). CONCLUSIONS: Deferring coronary interventions of intermediate stenosis based on FFR measurement is safe with respect to long-term follow-up, irrespective of the extent of coronary artery disease.

Angioplasty, Balloon, Coronary↗

Measurement of myocardial fractional flow reserve is a cost-effective way to identify coronary artery lesions of indeterminate severity that warrant revascularisation.

BACKGROUND: The RADI pressure wire may be used in stenotic coronary arteries to calculate myocardial fractional flow reserve (FFR(myo)), the ratio between distal hyperaemic coronary pressure and aortic pressure. A ratio less than 0.75 categorizes lesions of haemodynamic significance for which percutaneous coronary intervention (PCI) or coronary artery bypass surgery (CABG) may be warranted. We undertook this study to evaluate the cost implications of performing these measurements. METHODS: We recorded FFR(myo) using RADI wires in 32 coronary artery lesions of between 30 and 60% diameter stenosis in 31 patients and assessed how this information changed our management. RESULTS: We followed our original "management plan" in only eight patients. PCI or CABG was performed in eight whose lesions were characterised by a FFR(myo) value of 0.76 or less. Myocardial perfusion imaging (MPI) was done in only one of nine for whom this had seemed to be appropriate. Two-thirds of those for whom PCI had appeared to be warranted were treated conservatively and only one quarter of the original "surgical" group underwent CABG. CONCLUSION: Although RADI pressure wires are an additional expense, it is appropriate to use them to assess coronary stenotic lesions of indeterminate severity. When we took into account the savings that arose from changes in management, the additional cost of measuring FFR(myo) was around dollar 580 per study.

Adult↗

Comparison of exercise electrocardiography and dobutamine echocardiography with invasively assessed myocardial fractional flow reserve in evaluation of severity of coronary arterial narrowing.

This study compares side-by-side exercise electrocardiography and dobutamine echocardiography with an invasively assessed index of myocardial flow (pressure-derived myocardial fractional flow reserve). The data show that ST-segment depression > or = 0.1 mV and the occurrence of new wall motion abnormalities during dobutamine infusion reflect a similar impairment of myocardial blood flow.

Cardiotonic Agents↗

Fractional myocardial flow reserve (FFRmyo) after coronary intervention as a predictor of chronic restenosis.

The angiographic assessment of coronary stenosis has many limitations, especially after coronary intervention. To determine the physiologic significance of such lesions, we measured the mean translesional pressure gradients at rest (P1), those during hyperemia induced by intracoronary administration of papaverine (12 mg in the left and 8 mg in the right coronary artery) (P2), and fractional myocardial flow reserve (FFRmyo) which is derived from the ratio of the mean distal coronary pressure and aortic pressure during hyperemia. Our objective was to determine the relations among P1, P2, and FFRmyo and restenosis as potential predictors of chronic restenosis. The grouped study consisted of 32 patients with ischemic heart disease scheduled to undergo intervention. The distal coronary pressure was measured using a 0.014 inch pressure monitoring wire (Pressure Guide, Radi Medical Systems, Uppsala, Sweden). The guidewire was advanced through the lesional segment. The mean percent diameter stenosis (%DS) was 67.9 +/- 13.3% before intervention and 22.9 +/- 15.3% after intervention. The mean P2 (9.9 +/- 5.3 mmHg) was significantly higher than the mean P1 (4.5 +/- 3.6 mmHg; p < 0.0001). There was no correlation of P1, P2 or FFRmyo with the %DS after intervention. Follow-up angiography (after 6 months) performed on all patients revealed restenosis (%DS > or =50%) in four patients (12.5%). There was no correlation between P1 and the %DS at the follow-up angiography, but the relation between P2, FFRmyo and the %DS at the follow-up angiography was significant (r = 0.599, p < 0.01; r = 0.703, p < 0.0001, respectively). As a measurement of P2, FFRmyo is useful for the determination of the endpoint of intervention in consideration of prevention of restenosis. A new endpoint may be established after further evaluation in a greater number of patients.

Aged↗