Tim Tödt

Outcomes 1 Year after Thrombus Aspiration for Myocardial Infarction

BACKGROUND Routine intracoronary thrombus aspiration before primary percutaneous coronary intervention (PCI) in patients with ST-segment elevation myocardial infarction (STEMI) has not been proved to reduce short-term mortality. We evaluated clinical outcomes at 1 year after thrombus aspiration. METHODS We randomly assigned 7244 patients with STEMI to undergo manual thrombus aspiration followed by PCI or to undergo PCI alone, in a registry-based, randomized clinical trial. The primary end point of all-cause mortality at 30 days has been reported previously. Death from any cause at 1 year was a prespecified secondary end point of the trial. RESULTS No patients were lost to follow-up. Death from any cause occurred in 5.3% of the patients (191 of 3621 patients) in the thrombus-aspiration group, as compared with 5.6% (202 of 3623) in the PCI-only group (hazard ratio, 0.94; 95% confidence interval [CI], 0.78 to 1.15; P=0.57). Rehospitalization for myocardial infarction at 1 year occurred in 2.7% and 2.7% of the patients, respectively (hazard ratio, 0.97; 95% CI, 0.73 to 1.28; P=0.81), and stent thrombosis in 0.7% and 0.9%, respectively (hazard ratio, 0.84; 95% CI, 0.50 to 1.40; P=0.51). The composite of death from any cause, rehospitalization for myocardial infarction, or stent thrombosis occurred in 8.0% and 8.5% of the patients, respectively (hazard ratio, 0.94; 95% CI, 0.80 to 1.11; P=0.48). The results were consistent across all the major subgroups, including grade of thrombus burden and coronary flow before PCI. CONCLUSIONS Routine thrombus aspiration before PCI in patients with STEMI did not reduce the rate of death from any cause or the composite of death from any cause, rehospitalization for myocardial infarction, or stent thrombosis at 1 year. (Funded by the Swedish Research Council and others; TASTE ClinicalTrials.gov number, NCT01093404.).

Instantaneous Wave-free Ratio versus Fractional Flow Reserve to Guide PCI

Background The instantaneous wave‐free ratio (iFR) is an index used to assess the severity of coronary‐artery stenosis. The index has been tested against fractional flow reserve (FFR) in small trials, and the two measures have been found to have similar diagnostic accuracy. However, studies of clinical outcomes associated with the use of iFR are lacking. We aimed to evaluate whether iFR is noninferior to FFR with respect to the rate of subsequent major adverse cardiac events. Methods We conducted a multicenter, randomized, controlled, open‐label clinical trial using the Swedish Coronary Angiography and Angioplasty Registry for enrollment. A total of 2037 participants with stable angina or an acute coronary syndrome who had an indication for physiologically guided assessment of coronary‐artery stenosis were randomly assigned to undergo revascularization guided by either iFR or FFR. The primary end point was the rate of a composite of death from any cause, nonfatal myocardial infarction, or unplanned revascularization within 12 months after the procedure. Results A primary end‐point event occurred in 68 of 1012 patients (6.7%) in the iFR group and in 61 of 1007 (6.1%) in the FFR group (difference in event rates, 0.7 percentage points; 95% confidence interval [CI], ‐1.5 to 2.8; P=0.007 for noninferiority; hazard ratio, 1.12; 95% CI, 0.79 to 1.58; P=0.53); the upper limit of the 95% confidence interval for the difference in event rates fell within the prespecified noninferiority margin of 3.2 percentage points. The results were similar among major subgroups. The rates of myocardial infarction, target‐lesion revascularization, restenosis, and stent thrombosis did not differ significantly between the two groups. A significantly higher proportion of patients in the FFR group than in the iFR group reported chest discomfort during the procedure. Conclusions Among patients with stable angina or an acute coronary syndrome, an iFR‐guided revascularization strategy was noninferior to an FFR‐guided revascularization strategy with respect to the rate of major adverse cardiac events at 12 months. (Funded by Philips Volcano; iFR SWEDEHEART ClinicalTrials.gov number, NCT02166736.)

Functional measurements based on feature tracking of cine magnetic resonance images identify left ventricular segments with myocardial scar

BackgroundThe aim of the study was to perform a feature tracking analysis on cine magnetic resonance (MR) images to elucidate if functional measurements of the motion of the left ventricular wall may detect scar defined with gadolinium enhanced MR.Myocardial contraction can be measured in terms of the velocity, displacement and local deformation (strain) of a particular myocardial segment. Contraction of the myocardial wall will be reduced in the presence of scar and as a consequence of reduced myocardial blood flow.MethodsThirty patients (3 women and 27 men) were selected based on the presence or absence of extensive scar in the anteroseptal area of the left ventricle. The patients were investigated in stable clinical condition, 4-8 weeks post ST-elevation myocardial infarction treated with percutaneous coronary intervention. Seventeen had a scar area >75% in at least one anteroseptal segment (scar) and thirteen had scar area <1% (non-scar). Velocity, displacement and strain were calculated in the longitudinal direction, tangential to the endocardial outline, and in the radial direction, perpendicular to the tangent.ResultsIn the scar patients, segments with scar showed lower functional measurements than remote segments. Radial measurements of velocity, displacement and strain performed better in terms of receiver-operator-characteristic curves (ROC) than the corresponding longitudinal measurements. The best area-under-curve was for radial strain, 0.89, where a cut-off value of 38.8% had 80% sensitivity and 86% specificity for the detection of a segment with scar area >50%. As a percentage of the mean, intraobserver variability was 16-14-26% for radial measurements of displacement-velocity-strain and corresponding interobserver variability was 13-12-18%.ConclusionFeature tracking analysis of cine-MR displays velocity, displacement and strain in the radial and longitudinal direction and may be used for the detection of transmural scar. The accuracy and repeatability of the radial functional measurements is satisfactory and global measures agree.

Stent thrombosis in new-generation drug-eluting stents in patients with STEMI undergoing primary PCI: a report from SCAAR.

BACKGROUND Some concerns still have not been resolved about the long-term safety of drug-eluting stents (DES) in patients with acute STEMI. OBJECTIVES The aim of this study was to evaluate the stent thrombosis (ST) rate up to 3 years in patients with ST-segment elevation myocardial infarction (STEMI) treated by primary percutaneous coronary intervention (PCI) with new-generation drug-eluting stents (n-DES) compared with bare-metal stents (BMS) and old-generation drug-eluting stents (o-DES) enrolled in the SCAAR (Swedish Coronary Angiography and Angioplasty Registry). METHODS From January 2007 to January 2013, 34,147 patients with STEMI were treated by PCI with n-DES (n = 4,811), o-DES (n = 4,271), or BMS (n = 25,065). The risks of early/late (up to 1 year) and very late definite ST (after 1 year) were estimated. RESULTS Cox regression landmark analysis showed a significantly lower risk of early/late ST in patients treated with n-DES (hazard ratio [HR]: 0.65; 95% confidence interval [CI]: 0.43 to 0.99; p = 0.04) and o-DES (HR: 0.60; 95% CI: 0.41 to 0.89; p = 0.01) compared with the BMS group. The risk of very late ST was similar between the n-DES and BMS groups (HR: 1.52; 95% CI: 0.78 to 2.98; p = 0.21), whereas a higher risk of very late ST was observed with o-DES compared with BMS (HR: 2.88; 95% CI: 1.70 to 4.89; p < 0.01). CONCLUSIONS Patients treated with n-DES have a lower risk of early/late ST than patients treated with BMS. The risk of very late ST is low and comparable between n-DES and BMS up to 3 years of follow-up, whereas o-DES treatment is associated with an increased risk of very late ST. The current STEMI guidelines might require an update in light of the results of this and other recent studies.

Bivalirudin versus Heparin Monotherapy in Myocardial Infarction

BACKGROUND The comparative efficacy of various anticoagulation strategies has not been clearly established in patients with acute myocardial infarction who are undergoing percutaneous coronary intervention (PCI) according to current practice, which includes the use of radial‐artery access for PCI and administration of potent P2Y12 inhibitors without the planned use of glycoprotein IIb/IIIa inhibitors. METHODS In this multicenter, randomized, registry‐based, open‐label clinical trial, we enrolled patients with either ST‐segment elevation myocardial infarction (STEMI) or non‐STEMI (NSTEMI) who were undergoing PCI and receiving treatment with a potent P2Y12 inhibitor (ticagrelor, prasugrel, or cangrelor) without the planned use of glycoprotein IIb/IIIa inhibitors. The patients were randomly assigned to receive bivalirudin or heparin during PCI, which was performed predominantly with the use of radial‐artery access. The primary end point was a composite of death from any cause, myocardial infarction, or major bleeding during 180 days of follow‐up. RESULTS A total of 6006 patients (3005 with STEMI and 3001 with NSTEMI) were enrolled in the trial. At 180 days, a primary end‐point event had occurred in 12.3% of the patients (369 of 3004) in the bivalirudin group and in 12.8% (383 of 3002) in the heparin group (hazard ratio, 0.96; 95% confidence interval [CI], 0.83 to 1.10; P=0.54). The results were consistent between patients with STEMI and those with NSTEMI and across other major subgroups. Myocardial infarction occurred in 2.0% of the patients in the bivalirudin group and in 2.4% in the heparin group (hazard ratio, 0.84; 95% CI, 0.60 to 1.19; P=0.33), major bleeding in 8.6% and 8.6%, respectively (hazard ratio, 1.00; 95% CI, 0.84 to 1.19; P=0.98), definite stent thrombosis in 0.4% and 0.7%, respectively (hazard ratio, 0.54; 95% CI, 0.27 to 1.10; P=0.09), and death in 2.9% and 2.8%, respectively (hazard ratio, 1.05; 95% CI, 0.78 to 1.41; P=0.76). CONCLUSIONS Among patients undergoing PCI for myocardial infarction, the rate of the composite of death from any cause, myocardial infarction, or major bleeding was not lower among those who received bivalirudin than among those who received heparin monotherapy. (Funded by the Swedish Heart–Lung Foundation and others; VALIDATE‐SWEDEHEART ClinicalTrialsRegister.eu number, 2012–005260–10; ClinicalTrials.gov number, NCT02311231.)

Gender difference in prevalence and prognostic impact of renal insufficiency in patients with ST-elevation myocardial infarction treated with primary percutaneous coronary intervention

Objective To evaluate if female gender is associated with renal insufficiency in patients with ST-elevation myocardial infarction (STEMI) and if there is a gender difference in the prognostic importance of renal insufficiency in STEMI. Design Single-centre observational study. Setting One tertiary cardiac centre. Patients All consecutive patients with STEMI planned for primary percutaneous coronary intervention in one Swedish county in 2005 (98 women and 176 men). Main outcome measures Logistic regression analyses were conducted to evaluate the predictors of renal insufficiency, associations between estimated glomerular filtration rate (eGFR) and outcome in each gender and a possible interaction between gender and eGFR regarding outcome. Results Renal insufficiency was defined as eGFR less than 60 ml/min per 1.73 m2. 67% of women had renal insufficiency compared with 26% of men, OR 5.06 (95% CI 2.66 to 9.59) after multivariable adjustment. In women each 10 ml/min per 1.73 m2 increment of eGFR was associated with a 63% risk reduction for 1-year mortality, OR 0.37 (95% CI 0.15 to 0.89). No such association was found in men, OR 1.05 (95% CI 0.63 to 1.76). A trend towards a significant interaction between gender and eGFR regarding 1-year mortality was found, OR 2.05 (95% CI 0.93 to 4.50). Conclusions A considerable gender difference in the prevalence of renal insufficiency in STEMI was found and renal insufficiency seemed to be a more important prognostic marker in women. These results are important as previous STEMI studies have shown higher multivariable adjusted mortality in women than in men but renal function has seldom been taken into consideration.

Longitudinal peak strain detects a smaller risk area than visual assessment of wall motion in acute myocardial infarction

BackgroundOpening of an occluded infarct related artery reduces infarct size and improves survival in acute ST-elevation myocardial infarction (STEMI). In this study we performed tissue Doppler analysis (peak strain, displacement, mitral annular movement (MAM)) and compared with visual assessment for the study of the correlation of measurements of global, regional and segmental function with final infarct size and transmurality. In addition, myocardial risk area was determined and a prediction sought for the development of infarct transmurality ≥50%.MethodsTwenty six patients with STEMI submitted for primary percutaneous coronary intervention (PCI) were examined with echocardiography on the catheterization table. Four to eight weeks later repeat echocardiography was performed for reassessment of function and magnetic resonance imaging for the determination of final infarct size and transmurality.ResultsOn a global level, wall motion score index (WMSI), ejection fraction (EF), strain, and displacement all showed significant differences (p ≤ 0.001, p ≤ 0.001, p ≤ 0.001 and p = 0.03) between the two study visits, but MAM did not (p = 0.17). On all levels (global, regional and segmental) and both pre- and post PCI, WMSI showed a higher correlation with scar transmurality compared to strain. We found that both strain and WMSI predicted the development of scar transmurality ≥50%, but strain added no significant information to that obtained with WMSI in a logistic regression analysis.ConclusionsIn patients with acute STEMI, WMSI, EF, strain, and displacement showed significant changes between the pre- and post PCI exam. In a ROC-analysis, strain had 64% sensitivity at 80% specificity and WMSI around 90% sensitivity at 80% specificity for the detection of scar with transmurality ≥50% at follow-up.

Strategies TO reduce time delays in patients with AcuTe coronary heart disease treated with primary PCI--the STOP WATCH study: a multistage action research project.

Objective To identify, evaluate and reduce system delay times in an ST-elevation myocardial infarction (STEMI) network by targeted reorganisation of logistics and personal feedback to staff on time delays. Design Multistage action research project. Three study phases were used (exploration, tailored intervention and evaluation). Setting Single centre study, Sweden. Patients Consecutive patients (N=156) with prehospital STEMI onset treated with primary percutaneous coronary intervention (PCI). Interventions Areas of delays were identified through participant observations and collaborative discussions. To increase the awareness of delay factors, continuous feedback on time delays was given. Elements of the logistics’ reorganisation were (1) prioritised ECG recording by emergency medical services personnel, (2) central evaluation of ECG in all patients and (3) start of PCI procedure when two of three PCI team members were on site. Multiple key time measurements were made before (N=67) and after (N=89) the intervention. Main outcomes Time difference (minutes) in system delay between the preintervention and postintervention phases. Results Time from first medical contact (FMC) to a patent artery and time from FMC-to-catheter laboratory (cath-lab) arrival decreased by 6 and 12 min, respectively (ns). Time from FMC-to-ECG recording remained unchanged after the intervention. Time from ECG to decision for primary PCI was reduced by 6 min, p=0.004 and time from ECG-to-cath-lab arrival by 11 min, p=0.02. Total time from diagnosis to a patent artery decreased by 11 min (ns). Conclusions Identification of time delays in an STEMI network with awareness of delay factors, reorganisation of logistics and continuous feedback can reduce system delay times significantly.

Relationship between treatment delay and final infarct size in STEMI patients treated with abciximab and primary PCI

BackgroundStudies on the impact of time to treatment on myocardial infarct size have yielded conflicting results. In this study of ST-Elevation Myocardial Infarction (STEMI) treated with primary percutaneous coronary intervention (PCI), we set out to investigate the relationship between the time from First Medical Contact (FMC) to the demonstration of an open infarct related artery (IRA) and final scar size.Between February 2006 and September 2007, 89 STEMI patients treated with primary PCI were studied with contrast enhanced magnetic resonance imaging (ceMRI) 4 to 8 weeks after the infarction. Spearman correlation was computed for health care delay time (defined as time from FMC to PCI) and myocardial injury. Multiple linear regression was used to determine covariates independently associated with infarct size.ResultsAn occluded artery (Thrombolysis In Myocardial Infarction, TIMI flow 0-1 at initial angiogram) was seen in 56 patients (63%). The median FMC-to-patent artery was 89 minutes. There was a weak correlation between time from FMC-to-patent IRA and infarct size, r = 0.27, p = 0.01. In multiple regression analyses, LAD as the IRA, smoking and an occluded vessel at the first angiogram, but not delay time, correlated with infarct size.ConclusionsIn patients with STEMI treated with primary PCI we found a weak correlation between health care delay time and infarct size. Other factors like anterior infarction, a patent artery pre-PCI and effects of reperfusion injury may have had greater influence on infarct size than time-to-treatment per se.

Early treatment with abciximab in patients with ST elevation myocardial infarction results in a high rate of normal or near normal blood flow in the infarct related artery

Abstract There is debate whether early treatment with GpIIb/IIIa inhibitors is of clinical benefit in primary percutaneous coronary intervention (PCI) for ST-elevation myocardial infarction (STEMI). This study explored the effects of early given abciximab on coronary blood flow and major adverse cardiac events (MACE) in patients with STEMI treated with primary PCI and adjunctive abciximab. We studied all consecutive patients from our catchment area with STEMI undergoing acute angiography with the intention of primary PCI during 2005. Abciximab was given as early pre-treatment before, (n = 133) or at the cath. lab. after a diagnostic angiography (n = 109). Pre-procedural TIMI 2–3 flow was observed in 45.9 % of patients in the early group versus 20.2 % in the cath. lab. group, P = 0.0001. Mortality rates were 3.8 % versus 3.7% inhospital and 8.3 % versus 7.3% at one year in the early respectively the cath. lab. group, both P = NS. The MACE rate (death, non fatal myocardial infarction, unplanned revascularization) at one year was 19.5 % (early group) and 26.6 % (cath. lab. group), P = 0.19. CONCLUSION: In this single centre registry study of unselected patients with STEMI early given abciximab was associated with a significantly higher rate of TIMI 2–3 flow compared to abciximab given after the acute angiography.