Intravascular ultrasound correlates of corrected TIMI framecount

The TIMI frame count (TFC) is an index of coronary blood flow, and a correction in TFC (CTFC) for left anterior descending artery (LAD) has also been proposed. However, the relationship between TFC and intravascular ultrasound (IVUS) parameters of culprit coronary arteries has not been reported. The aim of this study was to investigate IVUS-derived correlates of TFC before and after stenting, and to assess the validation of its correction for LAD. The study population was comprised of 38 patients with acute coronary syndrome or stable coronary artery disease studied by IVUS before and after stenting (LAD 21, circumflex 8, right coronary artery 9). For LAD, CTFC was calculated by dividing the TFC by 1.7. Preintervention luminal % area stenosis was 82 +/- 12.3%. Pre- and postintervention target lesion lumen areas were 1.8 +/- 0.5 mm2 and 8.5 +/- 0.5 mm2 (P<0.0001), and CTFC were 35.3 +/- 16.8 and 16.9 +/- 4.3 (P<0.0001), respectively. In the 76 IVUS studies, CTFC showed a good correlation to luminal % area stenosis (r = 0.69, P<0.001), and a good and negative correlation to target lesion lumen area (r = -0.70, P<0.001). Postprocedural improvement in CTFC showed a modest correlation to acute lumen gain (r = 0.5, P<0.05). With respect to culprit arteries, pre and postintervention IVUS parameters and CTFC, and net CTFC change after stenting were not different (P>0.05). However, uncorrected TFC of LAD was significantly higher than both the CTFC of LAD and TFC of the other two coronary arteries (P<0.05). We conclude that CTFC is closely correlated to target lesion luminal area and luminal % area stenosis whereas a modest correlation is present between improvement in CTFC and acute luminal gain due to stenting. Results from different coronary arteries with comparable IVUS parameters seem to support the validity of a correction in TFC.     

Can thrombolytic therapy provide beneficial effects additional to epicardial coronary artery recanalization? A study based on coronary pressure measurement

BACKGROUND: Collaterals provide significant blood supply to the myocardium at risk and the presence of a preserved and adequate collateral network may limit microvascular damage during the occlusion of an epicardial coronary artery. The aim of this study was to evaluate whether thrombolytic therapy (TT) may produce beneficial effects at the level of microvascular circulation in addition to epicardial coronary artery recanalization by using quantitative intracoronary pressure measurement techniques in patients with recent acute myocardial infarction (AMI). MATERIALS AND METHODS: Thirty-six patients who presented with AMI and had preinfarction angina pectoris, more than 60% stenosis and thrombolysis in myocardial infarction (TIMI) grade II flow in the infarct-related artery and who underwent a stent implantation procedure within 10 days of AMI were included in this study. Seventeen of 36 patients had received TT (group 1) and 19 had not received TT due to presence of contraindications or late admission (group 2). Quantitative coronary angiography, TIMI frame count (TFC) assessment and intracoronary pressure measurements were performed before and after stent implantation for all patients. Myocardial fractional flow reserve (FFRmyo) was calculated as the ratio of mean distal coronary pressure to mean aortic pressure. During total occlusion with balloon inflation, distal pressure was recorded as coronary wedge pressure (CWP). Collateral flow index (CFI) was determined by the ratio of simultaneously measured CWP to mean aortic pressure. RESULTS: There were no differences between the two groups with respect to mean per cent stenosis and mean FFRmyo both before and after stent implantation. The mean CWP (25.1 +/- 8.6 mmHg compared with 17.2 +/- 6.2 mmHg, P < 0.01) and CFI (0.24 +/- 0.10 compared with 0.16 +/- 0.11, P < 0.01) were significantly higher and mean post-stent corrected TFC (18.8 +/- 3.7 compared with 22.4 +/- 3.1, P < 0.01) was significantly faster in the group of patients who had received TT compared to those who had not. CONCLUSIONS: We concluded that destruction degree of collateral circulation and distal microvasculature is lower in patients who had received TT, compared to patients who could not be treated with TT. Besides protective effect on collateral vessels, TT provides even more reperfusion and less destruction of the microvasculature.     

The superiority of TIMI frame count in detecting coronary flow changes after coronary stenting compared to TIMI Flow Classification

AIMS: We compared the qualitative Thombolysis in Myocardial Infarction (TIMI) Flow Classification with a new quantitative method, the TIMI Frame Count, to investigate the differences of both systems in detecting coronary flow changes after stent implantation. METHODS: TIMI flow grades and corrected TIMI frame counts (CTFC) were determined in 102 patients before, after stent implantation and at 6-month angiography. Analysis of the CTFC in patients with TIMI flow grades 3 and 2 demonstrated that for CTFC values lower than 30 frames, all patients had TIMI flow grade 3, while for CTFC values greater than 69 frames no patient had TIMI grade 3 flow. For CTFC values between 30 and 69 frames, TIMI grades 3 and 2 flow overlap. Comparing changes in TIMI flow grades and the CTFC before and after stent implantation (after stent implantation and at 6 month angiography), CTFC detects flow changes in 46% (40%) of the patients, which were not detected with TIMI Flow Classification. CONCLUSION: The TIMI Flow Classification grading system is not able to separate clearly between completely perfused and partially perfused coronary artery vessels. The quantitative TIMI Frame Count method is superior to the qualitative TIMI Flow Classification in detecting coronary flow changes.     

Assessing coronary blood flow with TIMI frame count method in isolated myocardial bridging

Myocardial bridging (MB) is a congenital anomaly of coronary arteries and its functional significance remains controversial. Using the TIMI frame count (TFC) method, the authors investigated whether the coronary blood flow velocity is decreased in MB. The study included 18 patients (group 1; 12 men and 6 women; mean age 50 +/-6 years) who had angiographically proven MB and otherwise normal coronary arteries and 20 subjects (group 2; 13 men and 7 women; mean age 50 +/-7 years) with normal-appearing coronary arteriograms. TFC of each group was determined and correlation between TFC and various factors including percent systolic narrowing, age, gender, body mass index, blood pressure, and echocardiographic parameters (ejection fraction, left-right ventricle wall thickness, and diameters) was investigated. Baseline characteristics were similar in the groups. All of the MB was localized to the left anterior descending (LAD) artery. Corrected TFC(LAD) frame count (CTFC) was significantly higher in group 1 than in group 2 (24.7 +/-2.1 vs 22.1 +/-1.9 frames/s, p = 0.001). Circumflex and right coronary artery frames counts were similar in the groups (22.4 +/-2.4 vs 21.3 +/-2.3 frames/s, p = 0.18, 23.1 +/-2.2 vs 23.4 +/-2.1 frames/s, p = 0.7) On correlation analysis, there was no correlation between TFC and the factors investigated. CTFC of patients with MB was higher than of those with normal coronary arteries, irrespective of the degree of systolic narrowing. This may suggest that coronary blood flow is decreased in patients with MB compared to patients having normal coronary arteries.     

Impaired coronary blood flow in nonculprit arteries in the setting of acute myocardial infarction. The TIMI Study Group. Thrombolysis in myocardial infarction.

OBJECTIVES AND BACKGROUND: While attention has focused on coronary blood flow in the culprit artery in acute myocardia infarction (MI), flow in the nonculprit artery has not been studied widely, in part because it has been assumed to be normal. We hypothesized that slower flow in culprit arteries, larger territories infarcted and hemodynamic perturbations may be associated with slow flow in nonculprit arteries. METHODS: The number of frames for dye to first reach distal landmarks (corrected TIMI [Thrombolysis in Acute Myocardial Infarction] frame count [CTFC]) were counted in 1,817 nonculprit arteries from the TIMI 4, 10A, 10B and 14 thrombolytic trials. RESULTS: Nonculprit artery flow was slowed to 30.9 +/- 15.0 frames at 90 min after thrombolytic administration, which is 45% slower than normal flow in the absence of acute MI (21 +/- 3.1, p < 0.0001). Patients with TIMI grade 3 flow in the culprit artery had faster nonculprit artery CTFCs than those patients with TIMI grades 0, 1 or 2 flow (29.1 +/- 13.7, n = 1,050 vs. 33.3 +/- 16.1, n = 752, p < 0.0001). The nonculprit artery CTFC improved between 60 and 90 min (3.3 +/- 17.9 frames, n = 432, p = 0.0001), and improvements were related to improved culprit artery flow (p = 0.0005). Correlates of slower nonculprit artery flow included a pulsatile flow pattern (i.e., systolic flow reversal) in the nonculprit artery (p < 0.0001) and in the culprit artery (p = 0.01), a left anterior descending artery culprit artery location (p < 0.0001), a decreased systolic blood pressure (p = 0.01), a decreased ventriculographic cardiac output (p = 0.02), a decreased double product (p = 0.0002), a greater percent diameter stenosis of the nonculprit artery (p = 0.01) and a greater percent of the culprit artery bed lying distal to the stenosis (p = 0.04). Adjunctive percutaneous transluminal coronary angioplasty (PTCA) of the culprit artery restored a culprit artery CTFC (30.4 +/- 22.2) that was similar to that in the nonculprit artery at 90 min (30.2 +/- 13.5), but both were slower than normal CTFCs (21 +/- 3.1, p < 0.0005 for both). If flow in the nonculprit artery was abnormal (CTFC > or = 28 frames) then the CTFC after PTCA in the culprit artery was 17% slower (p = 0.01). Patients who died had slower global CTFCs (mean CTFC for the three arteries) than patients who survived (46.8 +/- 21.3, n = 47 vs. 39.4 +/- 16.7, n = 1,055, p = 0.02). CONCLUSIONS: Acute MI slows flow globally, and slower global flow is associated with adverse outcomes. Relief of the culprit artery stenosis by PTCA restored culprit artery flow to that in the nonculprit artery, but both were 45% slower than normal flow.     

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.     

Blood flow velocity in donor coronary artery depends on the degree and pattern of collateral vessel development: a study using thrombolysis in myocardial infarction frame count method.

To understand the influence of collateral vessels on the coronary flow, TIMI frame count (TFC) method was applied as a measure of mean coronary blood flow velocity in artery giving collateral blood supply to the other artery in angiograms of 76 patients with single occluded coronary artery: RCA giving collaterals to occluded LAD or LAD giving collaterals to occluded RCA. As a control group, TFC was applied in angiograms of 30 patients with mild or no coronary artery disease. TFC was lower (faster blood flow) in LAD giving collaterals to occluded RCA (43 patients) than in LAD in control group (21.8 +/- 10.5 vs. 33.9 +/- 20.8 frames; P < 0.01). Higher degree of collateral vessels (Rentrop classification) and mixed- and distal-type collaterals (through the interventricular septum and heart apex) was associated with lower TFC. There was no difference in TFC in the RCA giving collaterals to an occluded LAD (33 patients) compared to the TFC in RCA in control group (16.6 +/- 9.0 vs. 18.5 +/- 6.0; P = NS), even in angiograms with higher degree of collateral vessel development. TFC was lower (faster blood flow) only in subgroups with mixed (proximal and distal types together in the same patient) and distal (through the interventricular septum and the apex of the heart) collateral types. A delayed contrast appearance in occluded LAD compared to occluded RCA has been found (35.1 +/- 16.1 vs. 20.2 +/- 7.3 frames; P < 0.001) with earlier contrast appearance in occluded LAD when proximal collateral vessels (through the conal and acute marginal branches of RCA) were presented. The coronary flow in donor arteries depends not only on the degree but also on the pattern of collateral vessels. The simple TFC method may facilitate the study of collateral filling pattern and offer insight into the influence of collaterals on the ventricular function.     

Increased thrombolysis in myocardial infarction frame count in patients with myocardial infarction and normal coronary arteriogram: a possible link between slow coronary flow and myocardial infarction

BACKGROUND: Thrombolysis in myocardial infarction (TIMI) frame count is a simple clinical tool for assessing quantitative indexes of coronary blood flow. This technique counts the number of cineangiographic frames from initial contrast opacification of the proximal coronary artery to opacification of distal arterial landmarks. We hypothesized that patients with normal coronary artery (NCA) and myocardial infarction (MI) might have impaired coronary flow. Accordingly, we assessed the TIMI frame counts of patients with NCA and MI and compared to patients with NCA and without MI. MATERIALS AND METHOD: This retrospective study included consecutive patients with MI and who were found to have normal coronary angiograms performed between 1999 and 2003. Fifty patients (group I) with NCA and MI were enrolled in the study. Fifty consecutive patients with NCA and without MI were also enrolled in the study as control group (group II). Mean time interval between MI and coronary angiography was 6 +/- 2 days. RESULTS: There were statistically significant differences between groups I and II in respect to gender (11 females (22%) versus 22 females (44%), p = 0.003, respectively) and smoking status (62% (31/50) versus 38% (19/50), p = 0.02). Comparison of TIMI frame counts between two groups revealed that group I patients had significantly higher TIMI frame counts than group two patients for all three coronary arteries (LAD: 40 +/- 12 versus 23 +/- 7, Cx: 47 +/- 14 versus 27 +/- 7, RCA: 36 +/- 10 versus 26 +/- 10, respectively, p < 0.001 for all). Smokers were significantly younger when compared to non-smokers (44 +/- 5 years versus 51 +/- 9 years, p = 0.008, respectively). TIMI frame counts of smokers did not significantly differ from those of non-smokers in group I patients. There were statistically significant differences between smokers and non-smokers in group II patients regarding TIMI frame counts for all three coronary arteries (LAD: 29 +/- 7 versus 18 +/- 3, LCX: 34 +/- 10 versus 22 +/- 4, RCA: 34+ /- 13 versus 20 +/- 4, respectively, p < 0.001 for all). CONCLUSION: We have shown that patients with MI and NCA have higher TIMI frame counts for all coronary arteries when compared to patients without MI and NCA. Absence of difference between smokers and non-smoker in the myocardial infarction group in respect to TIMI frame count, has suggested that smoking does not lead to further increase of TIMI frame counts. On the other hand, in patients without MI and with NCA, smokers have higher TIMI frame counts than non-smokers have.     

Postinfarctional remodeling: increased dye intensity in the myocardial risk area after angioplasty of infarct-related coronary artery is associated with reduction of ventricular volumes

OBJECTIVES: We sought to evaluate if angiographic dye videointensity of the risk area during percutaneous transluminal coronary angioplasty (PTCA) of the infarct-related artery (IRA) relates to remodeling. BACKGROUND: Poor reflow after myocardial infarction (MI) predicts worse ventricular remodeling. METHODS: Fifty-three patients with a first anterior MI and isolated disease of the left anterior descending (LAD), who underwent "primary" (n = 14), "rescue" (n = 7) or "late" (after 10 +/- 4 days, n = 32) PTCA, were retrospectively selected. In 10 patients prospectively collected, we assessed Doppler flow velocities and Doppler flow reserve (DFR), relating them to the videointensity technique. Coronary stenosis and TIMI flow were determined, and echocardiographic volumes (end-diastolic and end-systolic volume indexes) and regional asynergy were computed before hospital discharge (baseline) and at six months. Assuming higher peak videointensity reflects greater myocardial blood volume, a 1- to 5-point (poor-optimal) perfusion scale was devised. RESULTS: The correlation of Doppler peak velocity and DFR with videointensity was significant (r = 0.58, p = 0.007 and r = 0.71, p < 0.001, respectively). Patients were subdivided into group A (increased videointensity post-PTCA > or = 1.5 points, n = 29) and group B (unchanged videointensity, n = 24). Analysis of variance showed a time-group interaction for end-diastolic volume index (-4.6 +/- 23% vs. +22 +/- 22%, p = 0.003) and end-systolic volume index (-3.05 +/- 11.1% vs. +4.1 +/- 12.5%, p = 0.027). There was no interaction for changes in LAD stenosis (p = 0.39) and TIMI flow after PTCA (p = 0.27), or regional asynergy at six months (p = 0.31). CONCLUSIONS: Angiographic dye videointensity in the risk area correlates with Doppler peak velocity and DFR, and its increase after PTCA of IRA has a limiting effect on ventricular volumes, independent of coronary stenosis resolution, changes in Thrombolysis In Myocardial Infarction (TIMI) flow or extent of regional asynergy.     

Fractional flow reserve as a deciding criterion for intervention in patients with 50% coronary stenoses and impaired myocardial perfusion

BACKGROUND: A fractional flow reserve (FFRmyo) < 0.75 is a well validated parameter for significance of coronary stenoses in cases of normal myocardial function. We used the FFRmyo limit in patients with impaired myocardial perfusion by myocardial infarction and/or hypertension for intermediate stenoses of the LAD for decision to PTCA and checked the indication by clinical follow-up. METHODS: In 20 pts (5 women) with chest pain and visual 50 D% LAD stenoses, the FFRmyo was obtained by using a RADI-Pressure-Wire, the CFR by a densitometric technique (HODGSON), and the geometry of stenosis (minimal lumen diameter and diameter stenosis) by quantitative coronary angiography (QCA). EF and the kinetics of the anterolateral wall (expressed as radial shortening fraction) were measured by laevography. RESULTS: The mean age of our 20 pts. was 59.4 years: 13 of the pts. (65%) had a history of hypertension, 9 (45%) pts. a history of myocardial infarction. The mean diameter stenosis was 50.8%. The mean value of CFR was 2.9. The FFRmyo ranged from 0.66 to 0.90, the mean value was 0.78. The 12 pts. with FFRmyo > or = 0.75 (60%, group A) were treated with the usual anti-anginal medications. A PTCA was performed only in patients with FFRmyo < 0.75 (N = 8 (40%), group B). Except for one pt. with instent restenosis, in the 7 pts. with denovo stenoses stent implantation was performed. Significant differences between the groups A and B were seen only for the total number of myocardial infarctions (8/12 vs. 1/8) and diameter stenosis (48.5% vs. 54.3%). All lesions of group B had a diameter stenosis of 50% or higher. CFR correlated significantly with the radial shortening fraction (r = 0.75), minimal lumen diameter (r = -0.51) and diameter stenosis (r = -0.46). FFRmyo correlated with diameter stenosis (r = -0.47) only. All pts. treated with PTCA were primarily free of pain or reduced angina at least 1 CCS stage; only one developed an angina due to a restenosis (74 D%) 2 months after PTCA and stent implantation. The pts. of group A did not get worse, nor were they readmitted within 6 to 13 months after catheterization. CONCLUSIONS: Pts. with 50 D% stenoses, impaired myocardial perfusion and FFRmyo < 0.75 had a good long-term benefit concerning clinical and angiographic result. No pts. with FFRmyo < 0.75 had a D% lower than 50; therefore, the PTCA of intermediate stenoses without quantification must be avoided. CFR is not helpful for a decision to PTCA in such cases, because a normal value of CFR is relevant only.     

Incomplete expansion of Palmaz-Schatz stents despite high-pressure implantation technique: impact on target lesion revascularization.

Improved expansion of stents using high-pressure implantation technique with subsequent antiplatelet therapy has improved patient outcome regarding the incidence of subacute stent thrombosis, bleeding complications and restenosis. Whether high-pressure implantation per se guarantees adequate stent expansion remains unclear. The aim of the study was to determine (1) stent expansion after high-pressure implantation technique and (2) whether stent expansion influences rate of target lesion revascularization within 6 months of follow-up. One hundred Palmaz-Schatz stents were implanted in 98 lesions (91 native vessels, 7 graft vessels) of 94 patients using high-pressure implantation technique (balloon pressure 12-20 atm). Stent expansion was investigated using intravascular ultrasound imaging (IVUS). Clinical follow-up of the patients was performed for 6 months. After implantation, stent/mean reference ratio was 0.81 +/- 0.16. Noncompliant balloons used for implantation were chosen by angiographic criteria. Mean balloon/reference ratio was 1.08 +/- 0.22; therefore balloons were not undersized. Additional balloon dilataion using higher pressures and/or larger balloons based on IVUS criteria and subsequent IVUS measurements was performed in 52 patients (55%); in these patients, stent expansion improved from 79 +/- 16 to 91 +/- 15% (mean +/- SD) of average reference areas (p < 0.002). Within the 6 months' clinical follow-up, target lesion revascularization was performed in 19 patients (20%). The only prognostic factors for the development of in-stent restenosis requiring target lesion revascularization were the vessel size (p < 0.05) and the extent of plaque distal to the stents (p < 0.05). Implantation of Palmaz-Schatz stents using high-pressure technique does not guarantee adequate stent expansion. Additional dilatation with higher pressures and/or larger balloons improves stent expansion. The size of the stented vessel and the extent of plaque at the distal stent end (residual outflow stenosis) but not the degree of stent expansion were predictors for target lesion revascularization within 6 months' follow-up.     

Early administration of abciximab bolus in the emergency department improves angiographic outcome after primary PCI as assessed by TIMI frame count: results of the early ReoPro administration in myocardial infarction (ERAMI) trial.

OBJECTIVES: We assessed the safety and efficacy of early administration of abciximab prior to percutaneous coronary intervention (PCI) in acute myocardial infarction (AMI) patients. BACKGROUND: Research suggests that platelet glycoprotein IIb/IIIa receptor inhibitors, e.g. abciximab, may improve myocardial perfusion. In particular, early administration in the emergency department, prior to PCI, may result in more effective reperfusion. METHODS: Eighty AMI patients with planned PCI were randomized in a double-blind fashion to receive a 0.25 mg/kg abciximab bolus either "early" in the emergency department or "late" in the catheterization laboratory after angiographic assessment. In total, 74 patients underwent PCI after diagnostic angiography, all of which then received an abciximab infusion of 0.125 microg/kg/min for 12 hr. RESULTS: Prior to PCI, no significant differences were observed between the two groups regarding the angiographic endpoints or ST-segment resolution. After PCI, thrombolysis in MI (TIMI) frame count (TFC) was significantly improved in patients treated early rather than in those treated late (23 +/- 10 vs. 41 +/- 35; P = 0.02). Consistent trends, also favoring early treatment, were observed for TIMI flow grade 3 (TFG 3), corrected TFC (CTFC), and TIMI myocardial perfusion grade 3 (TMPG 3). Nine deaths (4 early, 5 late) and six significant bleeds (4 early, 2 late) were observed at 30 days after randomization. CONCLUSIONS: Early administration of abciximab is both feasible and safe in patients planned for primary PCI, increasing coronary flow and myocardial reperfusion after PCI, as demonstrated by significantly decreased TFC scores and trends toward improvements in TFG, CTFC, and TMPG.     

Elective coronary stent implantation in cardiogenic shock complicating acute myocardial infarction: in-hospital and six-month clinical and angiographic results.

Effective treatment of patients with acute myocardial infarction and cardiogenic shock depends on restoring persistent patency of the infarct-related artery. Coronary stenting, reducing abrupt or delayed closure related to dissection and suboptimal result, may improve PTCA results in cardiogenic shock. Eighteen patients (14 males and 4 females, mean age 59 +/- 7 years), referred to catheterization laboratory for acute myocardial infarction and shock, had elective stent implantation during 14 primary and 4 rescue PTCA. Time delay between shock onset and PTCA was 4.1 +/- 3 hr (range, 30 min to 12 hr). The IRA was LAD in seven patients (38%), LCx in two (11%), and RCA in eight (45%). One patient (5.%) had distal LMCA occlusion. Stent deployment was successful in 100% of patients and resulted in TIMI 3 flow in 13 (72%) patients. In 13 (72%) cases, cardiogenic shock gradually resolved and the patients were discharged alive. Five patients (28%) died because of irreversible hemodynamic deterioration without evidence of reinfarction. At 6-month follow-up, all the discharged patients were alive and no patient had reinfarction or recurrent angina. Heart transplant was required in one patient 5 months after stenting because of refractory congestive heart failure. Angiography demonstrated patency of all the coronary arteries treated, with TIMI 3 flow in all patients. Stent restenosis rate was 30%, and target lesion revascularization with CABG or re-PTCA was not required in any case. LV function improved from 39% +/- 15% to 51% +/- 15% (P < 0.01). Elective coronary stenting is an effective treatment for acute myocardial infarction complicated by cardiogenic shock and may improve acute and long-term survival.     

Differences in TIMI frame count following successful reperfusion with stenting or percutaneous transluminal coronary angioplasty for acute myocardial infarction

The Thrombolysis In Myocardial Infarction (TIMI) flow grade achieved in the infarct-related artery (IRA) during reperfusion therapy for acute myocardial infarction (AMI) is directly related to myocardial salvage. Recently, several series have demonstrated the safety of stenting in AMI and documented a larger postprocedure luminal diameter than that found at angioplasty, although no study has compared the effect of PTCA and stenting in AMI on flow characteristics of the IRA. The residual stenosis and the number of frames required to opacify standardized angiographic landmarks normalized for vessel length (corrected TIMI frame count) or compared with flow in a corresponding normal coronary artery (TIMI frame count index) were determined for the IRA of 39 patients who underwent angioplasty or stenting for AMI. Baseline characteristics were similar for the 20 patients who underwent stenting and the 19 patients who underwent percutaneous transluminal coronary angioplasty. After intervention, the luminal diameter was greater (3.24 vs 2.09 mm, p <0.0001) and the residual stenosis was less (-9.4% vs. 26.7%, p <0.0001) after stenting than after percutaneous transluminal coronary angioplasty. These changes in vessel geometry were associated with a lower corrected TIMI frame count (16.1 vs 30.7, p <0.002) and a lower TIMI frame count index (0.68 vs 1.3, p <0.002). Thus, stenting in AMI is associated with a greater postprocedure luminal diameter and improvement in coronary blood flow as measured by the TIMI frame count method.     

Direct coronary stenting: effect on coronary blood flow, immediate and late clinical results.

Direct stenting (DS) was attempted in 99 coronary lesions in 94 patients while standard stenting (SS) was attempted in 113 lesions in 103 patients matched for clinical characteristics, stenosis type, and location and stent type. The angiographic result was also evaluated according to TIMI frame count method (TFC) before and after procedure. A clinical follow-up was performed 1 year after the procedure. Before the procedure, TIMI grade 3 flow was detected in 42 cases (42.4%), grade 2 in 40 cases (40.4%), grade 1 in 5 cases (5.1%), and grade 0 in 12 cases (12.1%) in the DS group; these data were similar in SS group. After the procedure, TIMI grade flow was 3 in 90 cases (92.8%) in DS group and in 87 (77.0%) in SS group (P < 0.005); grade 2 was observed in 7 case (7.2%) in DS group and in 25 (22.1%) in SS group (P < 0.005). Major adverse cardiac events during hospitalization and at follow-up were similar in two groups. Radiation exposure time and procedure costs per lesion were significantly reduced in DS group compared to SS group (10.1 +/- 8 min vs. 13.9 +/- 4.7 min, P < 0.001; and 1901 +/- 687 Euro vs. 2352 +/- 743 Euro, P < 0.001, respectively). This study confirms that, in selected patients, direct stenting is a safe and successful procedure, allowing a significant reduction in radiation exposure time and procedural costs compared to standard stenting technique. The angiographic success is confirmed by the improvement in TFC in all cases.     

Effects of co-existence of coronary stenosis and the extent of coronary ectasia on the TIMI frame count in patients with coronary artery ectasia

The measurement of the thrombosis in myocardial infarction (TIMI) frame count is a simple method for evaluating coronary blood flow. Although it is well known that slow coronary flow is present in patients with coronary artery ectasia (CAE), the effects of coexisting stenosis and the severity of ectatic involvement on coronory flow have not been adequately studied. Thus, we examined (1) the effect of coexistence of obstructive coronary artery disease on TIMI frame count (TFC) and (2) the relation between the severity of ectatic involvement and TFC in patients with CAE. Ninety-seven study patients with CAE were examined in two steps to determine if they were appropriate in terms of the aim of this study. In the first step, ectasias were divided into three groups: an isolated CAE group, a CAE group with coexisting nonsignificant stenosis, and CAE with coexisting significant stenosis. In the second step, ectasias were subdivided into three groups: CAE with one segment, two segments, and three segments (or diffuse) involvement. The TIMI frame counts for the right coronary artery (RCA), the left circumflex coronary artery (LCx), and the left anterior descending artery (LAD) in the ectasia group were significantly higher than that of the control group (P < 0.001, P < 0.05, P < 0.05, respectively). The presence of coexisting nonsignificant stenosis or coexisting significant stenosis in patients with CAE did not influence TFC (P > 0.05, for all). In addition, the severity of ectasia involvement, regardless of the localization of ectatic segments and the type of the affected vessel, did not change the TFC (P > 0.05, for all). These results suggest that neither the coexisting stenosis nor the extent of involvement significantly affect TFC in patients with coronary ectasia.     

冠状动脉内支架术后心肌血流储备分数对心脏事件预测价值的研究

目的　研究冠状动脉(冠脉)内支架术后即刻心肌血流储备分数(myocardialfractionalflowresever ,FFRmyo)对于术后3个月心脏事件的预测价值,并建立目标FFRmyo值。方法　2 0 0 3年7月至2 0 0 3年9月单支病变的冠脉内支架术后行冠脉内压力测定的连续79例稳定型心绞痛患者,术后临床随访3个月,随访主要心脏事件发生(包括死亡、心肌梗死、再次靶病变血运重建术以及再发心绞痛) ,并采用Logistic回归分析主要心脏事件发生的相关因素、冠心病危险因素及介入治疗中的相关参数。结果　76名患者完成了3个月的临床随访,有1 4名患者( 1 8 .4 % )发生了心脏不良事件,其中1 2名患者再发心绞痛( 1 5 .8% ) ,2名患者再次行经皮冠脉介入术( 2. 6 % )。Logistic回归分析显示:支架术后FFRmyo是术后3个月心脏事件的独立预测因子,其预测价值显著优于冠脉造影所判断的残余狭窄率。据ROC曲线判断FFRmyo的界值为0 . 92。结论　冠脉内支架术后即刻FFRmyo对于术后3个月心脏事件发生有独立的预测价值。     

A pilot study with a new, rapid-exchange, thrombus-aspirating device in patients with thrombus-containing lesions: the Diver C.E. study.

BACKGROUND: In patients with acute coronary syndromes (ACS), distal embolization of thrombotic material is more likely to play a key role in the pathogenesis of myocardial no-reflow during percutaneous coronary intervention (PCI). Thus, interventional techniques able to reduce thrombus burden at the culprit vessel might improve final myocardial reperfusion. OBJECTIVE: To evaluate a new rapid-exchange thrombus-aspirating catheter, the Diver C.E., in patients with thrombotic coronary lesions undergoing PCI. METHODS: Fifty patients with acute myocardial infarction (n = 44) or with non-ST-elevation ACS and angiographic evidence of coronary thrombus (n = 6) undergoing urgent PCI were prospectively enrolled. The Diver C.E. was used to aspirate coronary thrombus from the culprit lesion after placement of the guidewire. Adjunctive balloon inflations and stent implantation were used to achieve good angiographic result. Angiographic coronary flow (by means of TIMI score and corrected TIMI frame count, cTFC), thrombus score (TS), and myocardial perfusion (by means of postintervention myocardial blush grade, MBG) were assessed in all patients. RESULTS: The device could be successfully employed in 96% of the cases (48/50) and yielded significant (P < 0.0001) acute reduction in thrombus burden (TS: predevice 3.5 +/- 0.8, postdevice 2.5 +/- 0.9) and improvement in coronary flow (TIMI grade: predevice 1.0 +/- 0.9, postdevice 2.0 +/- 0.9; CTFC predevice 71 +/- 31, postdevice 39 +/- 26). Final TIMI grade 0-1 was observed in one patient only (2%). A significant (P = 0.02) correlation was found between preintervention TS and efficacy of thrombus aspiration. A more pronounced acute reduction of thrombus burden after thrombus aspiration (TS reduction > or = 2) was associated with a better postintervention angiographic myocardial perfusion (MBG 2.3 +/- 0.9 vs 1.7 +/- 0.8; P = 0.05). CONCLUSIONS: This new, easy-to-use, device is able to reduce thrombus burden and to improve coronary flow in patients with thrombus-containing lesions. The improvement in myocardial perfusion associated to greater thrombus removal highlights the importance of thrombus aspiration in the management of thrombus-burdened coronary lesions.     

Effectiveness of adjunctive stent implantation following directional coronary atherectomy for treatment of left anterior descending ostial stenosis

The aim of this study was to evaluate the acute and long-term angiographic and clinical results of optimal plaque debulking by means of directional coronary atherectomy (DCA) followed by stent implantation for treatment of left anterior descending (LAD) ostial stenosis. Eighty consecutive patients (66 men; aged 57 +/- 10 years) with angina pectoris, documented anterior myocardial ischemia, and de novo LAD ostial stenosis prospectively underwent DCA and stent deployment. They were evaluated angiographically after 6 months and clinically for up to 30 +/- 29 months. The primary success rate was 98%. The in-hospital complications were 1 death due to in-stent subacute thrombosis 7 days after the procedure, 1 non-Q-wave myocardial infarction, and 1 retrograde left main artery dissection. The angiographic binary restenosis rate was 14.5%, and the loss index was 0.38 +/- 0.35. The target lesion revascularization (TLR) rates at 6, 12, and 24 months were 6.0%, 14.5%, and 16.3%, respectively, and the combined event rates (death, nonfatal myocardial infarction, TLR) at the same times were 8.7%, 17.5%, and 21.2%, respectively. These results indicate that the combined approach of DCA and stent implantation is feasible and safe in patients with LAD ostial lesions, has a high success rate, a low incidence of restenosis, and a good long-term outcome.     

急性心肌梗死直接冠状动脉介入术后心肌灌注的评价及其对近期预后的影响

目的研究急性心肌梗死(AMI)患者直接经皮冠状动脉介入治疗(d-PCI)后心肌灌注的主要影响因素及其对近期预后的影响。方法联合TIMI计帧分级(CTFC)与ST段的回落(STR)评价心肌灌注,并依此分为心肌灌注良好和灌注不良两组。观察两组患者的临床特点和随访6个月心室功能和主要心脏不良事件(MACE)。结果前壁梗死、IRA重建时间长是心肌灌注不良的独立危险因素。术后1周、1个月灌注不良组LVEF低于灌注良好组,而节段运动比率灌注不良组高于灌注良好组。两组患者PCI术后1个月左室收缩功能均较前改善,LVEF增加。随访6个月累计MACE、心力衰竭(心衰)的发生率灌注不良组高于灌注良好组(均P<0.05)。结论IRA重建时间与心肌灌注显著相关;心肌灌注显著影响AMI患者的心功能,灌注不良者近期MACE发生率高。