Use of the Instantaneous Wave-free Ratio or Fractional Flow Reserve in PCI.

BACKGROUND: Coronary revascularization guided by fractional flow reserve (FFR) is associated with better patient outcomes after the procedure than revascularization guided by angiography alone. It is unknown whether the instantaneous wave-free ratio (iFR), an alternative measure that does not require the administration of adenosine, will offer benefits similar to those of FFR. METHODS: We randomly assigned 2492 patients with coronary artery disease, in a 1:1 ratio, to undergo either iFR-guided or FFR-guided coronary revascularization. The primary end point was the 1-year risk of major adverse cardiac events, which were a composite of death from any cause, nonfatal myocardial infarction, or unplanned revascularization. The trial was designed to show the noninferiority of iFR to FFR, with a margin of 3.4 percentage points for the difference in risk. RESULTS: At 1 year, the primary end point had occurred in 78 of 1148 patients (6.8%) in the iFR group and in 83 of 1182 patients (7.0%) in the FFR group (difference in risk, -0.2 percentage points; 95% confidence interval [CI], -2.3 to 1.8; P<0.001 for noninferiority; hazard ratio, 0.95; 95% CI, 0.68 to 1.33; P=0.78). The risk of each component of the primary end point and of death from cardiovascular or noncardiovascular causes did not differ significantly between the groups. The number of patients who had adverse procedural symptoms and clinical signs was significantly lower in the iFR group than in the FFR group (39 patients [3.1%] vs. 385 patients [30.8%], P<0.001), and the median procedural time was significantly shorter (40.5 minutes vs. 45.0 minutes, P=0.001). CONCLUSIONS: Coronary revascularization guided by iFR was noninferior to revascularization guided by FFR with respect to the risk of major adverse cardiac events at 1 year. The rate of adverse procedural signs and symptoms was lower and the procedural time was shorter with iFR than with FFR. (Funded by Philips Volcano; DEFINE-FLAIR ClinicalTrials.gov number, NCT02053038 .).

Long-Term Effects of an Intensive Prevention Program After Acute Myocardial Infarction.

Effective long-term prevention after myocardial infarction (MI) is crucial to reduce recurrent events. In this study the effects of a 12-months intensive prevention program (IPP), based on repetitive contacts between non-physician "prevention assistants" and patients, were evaluated. Patients after MI were randomly assigned to the IPP versus usual care (UC). Effects of IPP on risk factor control, clinical events and costs were investigated after 24 months. In a substudy efficacy of short reinterventions after more than 24 months ("Prevention Boosts") was analyzed. IPP was associated with a significantly better risk factor control compared to UC after 24 months and a trend towards less serious clinical events (12.5% vs 20.9%, log-rank p = 0.06). Economic analyses revealed that already after 24 months cost savings due to event reduction outweighted the costs of the prevention program (costs per patient 1,070 € in IPP vs 1,170 € in UC). Short reinterventions ("Prevention Boosts") more than 24 months after MI further improved risk factor control, such as LDL cholesterol and blood pressure lowering. In conclusion, IPP was associated with numerous beneficial effects on risk factor control, clinical events and costs. The study thereby demonstrates the efficacy of preventive long-term concepts after MI, based on repetitive contacts between non-physician coworkers and patients.

Effects of an intensive long-term prevention programme after myocardial infarction - a randomized trial.

BACKGROUND: Long-term risk factor control after myocardial infarction (MI) is currently inadequate and there is an unmet need for effective secondary prevention programmes. DESIGN AND METHODS: It was the aim of the study to compare a 12-month intensive prevention programme (IPP), coordinated by prevention assistants and including education sessions, telephone visits and telemetric risk factor control, with usual care after MI. Three hundred and ten patients were randomized to IPP vs. usual care one month after hospital discharge for MI in two German heart centres. Primary study endpoint was the IPP Prevention Score (0-15 points) quantifying global risk factor control. RESULTS: Global risk factor control was strongly improved directly after MI before the beginning of the randomized study (30% increase IPP Prevention Score). During the 12-month course of the randomized trial the IPP Prevention Score was improved by a further 14.3% in the IPP group ( p < 0.001), while it decreased by 11.8% in the usual care group ( p < 0.001). IPP significantly reduced smoking, low-density lipoprotein cholesterol, systolic blood pressure and physical inactivity compared with usual care ( p < 0.05). Step counters with online documentation were used by the majority of patients (80%). Quality of life was significantly improved by IPP ( p < 0.05). The composite endpoint of adverse clinical events was slightly lower in the IPP group during 12 months (13.8% vs. 18.9%, p = 0.25). CONCLUSIONS: A novel intensive prevention programme after MI, coordinated by prevention assistants and using personal teachings and telemetric strategies for 12 months, was significantly superior to usual care in providing sustainable risk factor control and better quality of life.

Comparison of Major Adverse Cardiac Events Between Instantaneous Wave-Free Ratio and Fractional Flow Reserve-Guided Strategy in Patients With or Without Type 2 Diabetes: A Secondary Analysis of a Randomized Clinical Trial.

Importance: Invasive physiologic indices such as fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) are used in clinical practice. Nevertheless, comparative prognostic outcomes of iFR-guided and FFR-guided treatment in patients with type 2 diabetes have not yet been fully investigated. Objective: To compare 1-year clinical outcomes of iFR-guided or FFR-guided treatment in patients with and without diabetes in the Functional Lesion Assessment of Intermediate Stenosis to Guide Revascularization (DEFINE-FLAIR) trial. Design, Setting, and Participants: The DEFINE-FLAIR trial is a multicenter, international, randomized, double-blinded trial that randomly assigned 2492 patients in a 1:1 ratio to undergo either iFR-guided or FFR-guided coronary revascularization. Patients were eligible for trial inclusion if they had intermediate coronary artery disease (40%-70% diameter stenosis) in at least 1 native coronary artery. Data were analyzed between January 2014 and December 2015. Interventions: According to the study protocol, iFR of 0.89 or less and FFR of 0.80 or less were used as criteria for revascularization. When iFR or FFR was higher than the prespecified threshold, revascularization was deferred. Main Outcomes and Measures: The primary end point was major adverse cardiac events (MACE), defined as the composite of all-cause death, nonfatal myocardial infarction, or unplanned revascularization at 1 year. The incidence of MACE was compared according to the presence of diabetes in iFR-guided and FFR-guided groups. Results: Among the total trial population (2492 patients), 758 patients (30.4%) had diabetes. Mean age of the patients was 66 years, 76% were men (1868 of 2465), and 80% of patients presented with stable angina (1983 of 2465). In the nondiabetes population (68.5%; 1707 patients), iFR guidance was associated with a significantly higher rate of deferral of revascularization than the FFR-guided group (56.5% [n = 477 of 844] vs 46.6% [n = 402 of 863]; P < .001). However, it was not different between the 2 groups in the diabetes population (42.1% [n = 161 of 382] vs 47.1% [n = 177 of 376]; P = .15). At 1 year, the diabetes population showed a significantly higher rate of MACE than the nondiabetes population (8.6% vs 5.6%; adjusted hazard ratio [HR], 1.88; 95% CI, 1.28-2.64; P < .001). However, there was no significant difference in MACE rates between iFR-guided and FFR-guided groups in both the diabetes (10.0% vs 7.2%; adjusted HR, 1.33; 95% CI, 0.78-2.25; P = .30) and nondiabetes population (4.7% vs 6.4%; HR, 0.83; 95% CI, 0.51-1.35; P = .45) (interaction P = .25). Conclusions and Relevance: The diabetes population showed significantly higher risk of MACE than the nondiabetes population, even with the iFR-guided or FFR-guided treatment. The iFR-guided and FFR-guided treatment showed comparable risk of MACE and provided equal safety in selecting revascularization target among patients with diabetes. Trial Registration: ClinicalTrials.gov identifier: NCT02053038.

Sex Differences in Instantaneous Wave-Free Ratio or Fractional Flow Reserve-Guided Revascularization Strategy.

OBJECTIVES: This study sought to evaluate sex differences in procedural characteristics and clinical outcomes of instantaneous wave-free ratio (iFR)- and fractional flow reserve (FFR)-guided revascularization strategies. BACKGROUND: An iFR-guided strategy has shown a lower revascularization rate than an FFR-guided strategy, without differences in clinical outcomes. METHODS: This is a post hoc analysis of the DEFINE-FLAIR (Functional Lesion Assessment of Intermediate stenosis to guide Revascularization) study, in which 601 women and 1,891 men were randomized to iFR- or FFR-guided strategy. The primary endpoint was 1-year major adverse cardiac events (MACE), a composite of all-cause death, nonfatal myocardial infarction, or unplanned revascularization. RESULTS: Among the entire population, women had a lower number of functionally significant lesions per patient (0.31 ± 0.51 vs. 0.43 ± 0.59; p < 0.001) and less frequently underwent revascularization than men (42.1% vs. 53.1%; p < 0.001). There was no difference in mean iFR value according to sex (0.91 ± 0.09 vs. 0.91 ± 0.10; p = 0.442). However, the mean FFR value was lower in men than in women (0.83 ± 0.09 vs. 0.85 ± 0.10; p = 0.001). In men, an FFR-guided strategy was associated with a higher rate of revascularization than an iFR-guided strategy (57.1% vs. 49.3%; p = 0.001), but this difference was not observed in women (41.4% vs. 42.6%; p = 0.757). There was no difference in MACE rates between iFR- and FFR-guided strategies in both women (5.4% vs. 5.6%, adjusted hazard ratio: 1.10; 95% confidence interval: 0.50 to 2.43; p = 0.805) and men (6.6% vs. 7.0%, adjusted hazard ratio: 0.98; 95% confidence interval: 0.66 to 1.46; p = 0.919). CONCLUSIONS: An FFR-guided strategy was associated with a higher rate of revascularization than iFR-guided strategy in men, but not in women. However, iFR- and FFR-guided strategies showed comparable clinical outcomes, regardless of sex. (Functional Lesion Assessment of Intermediate Stenosis to guide Revascularization [DEFINE-FLAIR]; NCT02053038).

Clinical Events After Deferral of LAD Revascularization Following Physiological Coronary Assessment.

BACKGROUND: Physicians are not always comfortable deferring treatment of a stenosis in the left anterior descending (LAD) artery because of the perception that there is a high risk of major adverse cardiac events (MACE). The authors describe, using the DEFINE-FLAIR (Functional Lesion Assessment of Intermediate Stenosis to Guide Revascularisation) trial, MACE rates when LAD lesions are deferred, guided by physiological assessment using fractional flow reserve (FFR) or the instantaneous wave-free ratio (iFR). OBJECTIVES: The purpose of this study was to establish the safety of deferring treatment in the LAD using FFR or iFR within the DEFINE-FLAIR trial. METHODS: MACE rates at 1 year were compared between groups (iFR and FFR) in patients whose physiological assessment led to LAD lesions being deferred. MACE was defined as a composite of cardiovascular death, myocardial infarction (MI), and unplanned revascularization at 1 year. Patients, and staff performing follow-up, were blinded to whether the decision was made with FFR or iFR. Outcomes were adjusted for age and sex. RESULTS: A total of 872 patients had lesions deferred in the LAD (421 guided by FFR, 451 guided by iFR). The event rate with iFR was significantly lower than with FFR (2.44% vs. 5.26%; adjusted HR: 0.46; 95% confidence interval [CI]: 0.22 to 0.95; p = 0.04). This was driven by significantly lower unplanned revascularization with iFR and numerically lower MI (unplanned revascularization: 2.22% iFR vs. 4.99% FFR; adjusted HR: 0.44; 95% CI: 0.21 to 0.93; p = 0.03; MI: 0.44% iFR vs. 2.14% FFR; adjusted HR: 0.23; 95% CI: 0.05 to 1.07; p = 0.06). CONCLUSIONS: iFR-guided deferral appears to be safe for patients with LAD lesions. Patients in whom iFR-guided deferral was performed had statistically significantly lower event rates than those with FFR-guided deferral.

Stenting of unprotected left main stem stenosis: Results from a German single-centre registry.

OBJECTIVE: To elucidate the influence of drug-eluting stents (DESs) on interventional therapy of de novo unprotected left main stem (LMS) lesions in a hospital with on-site cardiac surgery. METHODS AND RESULTS: A retrospective study of all patients with unprotected LMS angioplasty from 1999 to 2005 was conducted with regard to clinical and procedural data, and follow-up data. Fifty-four patients with unprotected LMS stenosis were treated inter-ventionally. Of these patients, 16 were treated with DESs. Seven patients presented with cardiogenic shock. During their hospital stay, four patients died (all treated with bare metal stents [BMSs], three initially presenting with cardiogenic shock). Follow-up data for 53 patients (98%) were obtained. Median follow-up time was 24 months (25th percentile, 12 months; 75th percentile, 35 months). Survival after nine months was 87% (81% from the BMS-treated group, and 100% from the DES-treated group). Control angiography had been performed in 36 patients (67%). Patients with unprotected LMS with an angiographic follow-up had a higher nine-month survival rate than patients without (36 of 36 patients [100%] versus 10 of 17 patients [59%], respectively; P<0.0001). Target lesion revascularization rate was 19% in both the BMS and the DES groups. Methods of revascularization did not vary significantly between the groups. CONCLUSIONS: In the present study of selected patients with LMS stenosis, the use of DESs showed a low mortality rate but did not have a clear effect on target lesion revascularization rate compared with BMSs. A close follow-up appears to be mandatory to achieve acceptable results.

Influence of hydrostatic pressure on intracoronary indices of stenosis severity in vivo.

BACKGROUND: An influence of hydrostatic pressure on intracoronary indices of stenosis severity in vitro was recently reported. We sought to analyze the influence of hydrostatic pressure, caused by the height difference between the distal and proximal pressure sensor after guidewire positioning in the interrogated vessel, on intracoronary pressure measurements in vivo. METHODS AND RESULTS: In 30 coronary stenoses, intracoronary pressure measurements were performed in supine, left, and right lateral patient position. Height differences between the distal and proximal pressure sensor were measured by blinded observers. Measurement results of the position with the highest ("high") and lowest height difference ("low") were compared. In group "high", all measured indices were higher: mean difference of fractional flow reserve (FFR) 0.045 (SD 0.033, 95% CI 0.033-0.057, p < 0.0001), of instantaneous wave-free ratio (iFR) 0.043 (SD 0.04, 95% CI 0.029-0.057, p < 0.0001), and of resting Pd/Pa 0.037 (SD 0.034, 95% CI 0.025-0.049, p < 0.0001). Addition of the physically expectable hydrostatic pressure to the distal coronary pressures of the control group abolished the differences: corrected ∆FFR - 0.006 (SD 0.027, 95% CI - 0.015 to 0.004, p = 0.26), corrected ∆Pd/Pa - 0.008 (SD 0.03, 95% CI - 0.019 to 0.003, p = 0.18). Adjustment for hydrostatic pressure of FFR values in a standard supine position increased all values in anterior vessels and decreased all values in posterior vessels. The mean changes of FFR due to adjustment were: LAD - 0.048 (SD 0.016), CX 0.02 (SD 0.009), RCA 0.02 (SD 0.021). Dichotomous severity classification changed in 12.9% of stenoses. CONCLUSIONS: The study demonstrates a relevant influence of hydrostatic pressure on intracoronary indices of stenosis severity in vivo, caused by the height differences between distal and proximal pressure sensor.

Safety of the Deferral of Coronary Revascularization on the Basis of Instantaneous Wave-Free Ratio and Fractional Flow Reserve Measurements in Stable Coronary Artery Disease and Acute Coronary Syndromes.

OBJECTIVES: The aim of this study was to investigate the clinical outcomes of patients deferred from coronary revascularization on the basis of instantaneous wave-free ratio (iFR) or fractional flow reserve (FFR) measurements in stable angina pectoris (SAP) and acute coronary syndromes (ACS). BACKGROUND: Assessment of coronary stenosis severity with pressure guidewires is recommended to determine the need for myocardial revascularization. METHODS: The safety of deferral of coronary revascularization in the pooled per-protocol population (n = 4,486) of the DEFINE-FLAIR (Functional Lesion Assessment of Intermediate Stenosis to Guide Revascularisation) and iFR-SWEDEHEART (Instantaneous Wave-Free Ratio Versus Fractional Flow Reserve in Patients With Stable Angina Pectoris or Acute Coronary Syndrome) randomized clinical trials was investigated. Patients were stratified according to revascularization decision making on the basis of iFR or FFR and to clinical presentation (SAP or ACS). The primary endpoint was major adverse cardiac events (MACE), defined as the composite of all-cause death, nonfatal myocardial infarction, or unplanned revascularization at 1 year. RESULTS: Coronary revascularization was deferred in 2,130 patients. Deferral was performed in 1,117 patients (50%) in the iFR group and 1,013 patients (45%) in the FFR group (p < 0.01). At 1 year, the MACE rate in the deferred population was similar between the iFR and FFR groups (4.12% vs. 4.05%; fully adjusted hazard ratio: 1.13; 95% confidence interval: 0.72 to 1.79; p = 0.60). A clinical presentation with ACS was associated with a higher MACE rate compared with SAP in deferred patients (5.91% vs. 3.64% in ACS and SAP, respectively; fully adjusted hazard ratio: 0.61 in favor of SAP; 95% confidence interval: 0.38 to 0.99; p = 0.04). CONCLUSIONS: Overall, deferral of revascularization is equally safe with both iFR and FFR, with a low MACE rate of about 4%. Lesions were more frequently deferred when iFR was used to assess physiological significance. In deferred patients presenting with ACS, the event rate was significantly increased compared with SAP at 1 year.

Effect of Coronary Anatomy and Hydrostatic Pressure on Intracoronary Indices of Stenosis Severity.

OBJECTIVES: The authors sought to analyze height differences within the coronary artery tree in patients in a supine position and to quantify the impact of hydrostatic pressure on intracoronary pressure measurements in vitro. BACKGROUND: Although pressure equalization of the pressure sensor and the systemic pressure at the catheter tip is mandatory in intracoronary pressure measurements, subsequent measurements may be influenced by hydrostatic pressure related to the coronary anatomy in the supine position. Outlining and quantifying this phenomenon is important to interpret routine and pullback pressure measurements within the coronary tree. METHODS: Coronary anatomy was analyzed in computed tomography angiographies of 70 patients to calculate height differences between the catheter tip and different coronary segments in the supine position. Using a dynamic pressure simulator, the effect of the expected hydrostatic pressure resulting from such height differences on indices stenosis severity was assessed. RESULTS: In all patients, the left anterior and right posterior descending arteries are the highest points of the coronary tree with a mean height difference of -4.9 ± 1.6 cm and -3.8 ± 1.0 cm; whereas the circumflex artery and right posterolateral branches are the lowest points, with mean height differences of 3.9 ± 0.9 cm and 2.6 ± 1.6 cm compared with the according ostium. In vitro measurements demonstrated a correlation of the absolute pressure differences with height differences (r = 0.993; p < 0.0001) and the slope was 0.77 mm Hg/cm. The Pd/Pa ratio and instantaneous wave-free ratio correlated also with the height difference (fractional flow reserve r = 0.98; p < 0.0001; instantaneous wave-free ratio r = 0.97; p < 0.0001), but both were influenced by the systemic pressure level. CONCLUSIONS: Hydrostatic pressure variations resulting from normal coronary anatomy in a supine position influence intracoronary pressure measurements and may affect their interpretation during stenosis severity assessment.

Real-world use of fractional flow reserve in Germany: results of the prospective ALKK coronary angiography and PCI registry.

BACKGROUND: There is growing evidence for beneficial prognostic and economic effects of FFR-guided treatment of stable coronary artery disease. We sought to evaluate the real-world use of FFR measurements in patients undergoing elective coronary angiography. METHODS AND RESULTS: We analyzed the data of the prospective ALKK coronary angiography and PCI registry including data of 38 hospitals from January 2010 to December 2013. A total of 100,977 patients undergoing coronary angiography were included. In 3240 patients (3.2 %) intracoronary pressure measurement was performed. There was a wide range of use of FFR measurement in the different analyzed ALKK hospitals from 0.1 to 8.8 % in elective patients with suspected or known coronary artery disease (median 2.7 %, quartiles 0.9 and 5.3 %), with a successive increase of use over time during the study period. Overall, it was performed in 3.2 % of coronary angiographies. Use in patients with three-vessel disease (2.5 %) and recommendation for bypass surgery (1.6 %) was less frequent. In procedures without PCI, dose area product was higher in the FFR group (2641 cGy × cm2 vs. 2368 cGy × cm2, p < 0.001), while it was lower in procedures with ad hoc PCI (4676 cGy × cm2 vs. 5143 cGy × cm2, p < 0.001). The performing center turned out to be the strongest predictor. CONCLUSIONS: The use of FFR measurement was very heterogeneous between different hospitals and in general relatively low, in particular in patients with multivessel disease or recommendation for bypass surgery, but there was a positive trend during the study period. Technically, FFR measurement was not associated with an increased periprocedural complication rate.

Percutaneous endocardial injection of erythropoietin: assessment of cardioprotection by electromechanical mapping.

BACKGROUND: Apart from its well-known stimulation of erythropoiesis, erythropoietin (EPO) exhibits angiogenic and anti-apoptotic effects. These cellular protective effects have also been described in experimental acute myocardial infarction models. We investigated the effects of EPO in a porcine model of chronic progressive myocardial ischaemia. METHODS: At weeks 2 and 6 after implantation of a circumflex ameroid constrictor, endocardial electromechanical NOGA system (Biosense Webster, Inc., California, USA) mapping of the left ventricle, coronary and ventricular angiography, as well as echocardiography were performed. Two weeks after ameroid placement, 13 pigs were randomized with 7 pigs receiving 10.000 U EPO and 6 pigs receiving placebo into the ischaemic region using a NOGA guided percutaneous transendocardial injection catheter, MYOSTAR. After 6 weeks, histology (Masson's Trichrome) was analyzed. RESULTS: Endocardial electromechanical mapping showed an increase of mean unipolar voltage (UV) amplitude in the ischaemic myocardial segments in the EPO-treated animals (8.5 mV pre and 10.6 mV post treatment) and a significantly reduced ischaemic surface area compared to the control group (19% vs. 41%) suggesting a decline in ischaemic injury. Echocardiography revealed 2,2 hypokinetic segments of the lateral wall in the EPO group vs. 3,3 in the control groups. The mean ejection fraction was 64% in the EPO group and 55% in the placebo group. Quantitative histological analysis of the ischaemic regions revealed a reduction of myocardial fibrosis (8% vs. 28%) in the EPO group. CONCLUSION: Endocardial EPO injection may induce cardioprotective effects in hibernating myocardium and may attenuate the progression of ischaemic tissue damage.

Differences between automatically detected and steady-state fractional flow reserve.

BACKGROUND: Measurement of fractional flow reserve (FFR) has become a standard diagnostic tool in the catheterization laboratory. FFR evaluation studies were based on pressure recordings during steady-state maximum hyperemia. Commercially available computer systems detect the lowest Pd/Pa ratio automatically, which might not always be measured during steady-state hyperemia. We sought to compare the automatically detected FFR and true steady-state FFR. METHODS AND RESULTS: Pressure measurement traces of 105 coronary lesions from 77 patients with intermediate coronary lesions or multivessel disease were reviewed. In all patients, hyperemia had been achieved by intravenous adenosine administration using a dosage of 140 µg/kg/min. In 42 lesions (40%) automatically detected FFR was lower than true steady-state FFR. Mean bias was 0.009 (standard deviation 0.015, limits of agreement -0.02, 0.037). In 4 lesions (3.8%) both methods lead to different treatment recommendations, in all 4 cases instantaneous wave-free ratio confirmed steady-state FFR. CONCLUSIONS: Automatically detected FFR was slightly lower than steady-state FFR in more than one-third of cases. Consequently, interpretation of automatically detected FFR values closely below the cutoff value requires special attention.

Comparison of instantaneous wave-free ratio (iFR) and fractional flow reserve (FFR)--first real world experience.

BACKGROUND: The instantaneous wave-free ratio (iFR) is a new adenosine-independent index of coronary stenosis severity. Most published data have been based on off-line analyses of pressure recordings in a core laboratory. We prospectively compared real-time iFR and fractional flow reserve (FFR) measurements. METHODS AND RESULTS: iFR and FFR were measured in 151 coronary stenoses in 108 patients. Repeated iFR measurements were technically simple, showed excellent agreement [rs=0.99; p<0.0001], and the mean difference between consecutive iFR values was 0.0035 (limits of agreement: -0.019, 0.026). Mean iFR showed a significant correlation with FFR [rs=0.81; p<0.0001]. Receiver-operating characteristic analysis identified an optimal iFR cut-off value of 0.896 for categorization based on an FFR cut-off value 0.8. We compared two different iFR-based diagnostic strategies (iFR-only and hybrid iFR-FFR) with standard FFR: The iFR-only strategy showed good classification agreement (83.4%) with standard FFR. Use of the hybrid iFR-FFR strategy, assessing lesions in an iFR-gray zone of 0.86-0.93 by FFR, improved classification accuracy to 94.7%, and diagnosis would have been established in 61% of patients without adenosine-induced hyperemia. Notably, both iFR and FFR values were significantly higher in the posterior coronary vessels. CONCLUSIONS: Real-time iFR measurements are easily performed, have excellent diagnostic performance and confirm available off-line core laboratory data. The excellent agreement between repeated iFR measurements demonstrates the reliability of single measurements. Combining iFR with FFR in a hybrid strategy enhances diagnostic accuracy, exposing fewer patients to adenosine. Overall, iFR is a promising method, but still requires prospective clinical endpoint trial evaluation.

Use and impact of thrombectomy in primary percutaneous coronary intervention for acute myocardial infarction with persistent ST-segment elevation: results of the prospective ALKK PCI-registry.

BACKGROUND: Data about the impact of thrombectomy in primary percutaneous coronary intervention (PCI) are inconsistent. The aim of our study was an evaluation of both the real-world use of thrombectomy and the impact of thrombectomy on outcome in unselected patients treated with primary PCI for ST-elevation myocardial infarction (STEMI). METHODS AND RESULTS: We used the data of the prospective ALKK PCI-registry of 35 hospitals from January 2010 to December 2013. A total of 10,755 patients receiving single-vessel primary PCI for acute STEMI were included. In 2176 patients (20.2 %) thrombectomy was performed. There was a wide range of use of thrombectomy in the different ALKK hospitals from 1.1 to 61.7 % (median 18.6 %, quartiles 6.0 and 40.3 %) with a general increase of use over the first years of the study period. In patients with and without thrombectomy there was TIMI 0 flow present before PCI in 6010 patients, TIMI 1 in 1338, TIMI 2 in 2002, and TIMI 3 in 1405. Patients with acute heart failure or cardiogenic shock received significantly more often thrombectomy. Fluoroscopy time (8.1 vs. 7.3 min, p < 0.0001) and dose area product (5373 cGy × cm(2) vs. 4802 cGy × cm(2), p < 0.0001) were significantly higher in patients treated with thrombectomy. The subgroup of patients with TIMI 0 flow before PCI had significantly higher rates of TIMI 3 flow after PCI when treated with thrombectomy (87.1 vs. 84.1 %, p < 0.01), while there was no difference in post-PCI TIMI 3 flow in patients with TIMI 1, 2 or 3 flow before PCI. Rates of major adverse cardiac and cerebrovascular events were similar in both groups in general and in all subgroups of TIMI flow. CONCLUSIONS: The use of thrombectomy in patients with STEMI is heterogenous between hospitals. Overall, there was no impact of thrombectomy on TIMI 3 patency or mortality after PCI. In the subgroup of STEMI patients with TIMI 0 flow before PCI individualized thrombectomy had a positive impact on restoration of normal blood flow.

Early single-center experience in sutureless aortic valve implantation in 120 patients.

OBJECTIVE: The study objective was to evaluate the safety and efficacy of sutureless self-expanding nitinol stent-frame aortic valve prostheses made of equine pericardium implanted in patients with symptomatic aortic valve disease. METHODS: We performed a retrospective analysis of 120 patients (mean age, 76.7 ± 5.9 years) who underwent isolated aortic valve replacement or in combination with other cardiovascular procedures. Preoperatively, Society of Thoracic Surgeons score was determined. Transthoracic echocardiography and clinical outcome evaluation were performed at the time of discharge and at 6, 12, and 18 months follow-up, respectively. RESULTS: A total of 71 of 120 patients underwent isolated sutureless aortic valve replacement (mean aortic crossclamp time, 37 ± 11 minutes; mean bypass time, 62 ± 18 minutes). Coronary bypass grafting was performed in 30 patients. Overall mean Society of Thoracic Surgeons score was 14.8% ± 10%. Thirty-day mortality rate was 6.7% overall and 1.4% in stand-alone procedures. During a mean follow-up of 313 days, 3 more deaths occurred. The reoperation rate was 4.2%. Mean and peak transvalvular pressure gradients were 9 mm Hg (4-13 mm Hg) and 14 mm Hg (8-22 mm Hg) at discharge, respectively. In 8 patients (6.7%), permanent pacemaker implantation was necessary. No thromboembolic events or bleedings related to the bioprosthesis were observed. CONCLUSIONS: In this large single-center experience with sutureless aortic valve replacement, the surgical procedure is shown to be safe and time-saving. In view of the excellent hemodynamic results and shortening of aortic crossclamp and bypass times, we notice advantages especially in high-risk patients. Minimally invasive access seems to be facilitated. The long-term durability of this prosthesis has yet to be determined.

Use of drug-eluting stents in acute myocardial infarction with persistent ST-segment elevation: results of the ALKK PCI-registry.

BACKGROUND: Drug-eluting stents (DES) reduce the rate of in-stent restenosis (ISR) and target vessel revascularization significantly when compared with bare metal stents (BMS). Their beneficial effects have been demonstrated in patients with acute myocardial infarction also, but the use of DES in the latter population seems to be still limited in clinical practice. METHODS AND RESULTS: From January 2006 to December 2011, 25,424 patients with ST-elevation myocardial infarction were enrolled in the German ALKK PCI-registry. In 5,467 patients (21.5 %), a DES was implanted in the culprit segment, in 16,911 patients (66.5 %) a BMS, and 2,959 patients (11.6 %) received neither DES nor BMS. The rates of DES for typical subgroups were 31.7 % in patients with diabetes, 36.6 % in unprotected left main stenosis, 32.4 % in ostial lesions, 32.0 % for a stent length >15 mm, 26.2 % for a stent diameter ≤3 mm, and 58.5 % for ISR. There was a wide range in the use of DES between the different ALKK hospitals with a minimum of 2.3 % and a maximum of 58.3 % for the total study period (median 22.0 %, quartiles 14.6 and 37.5 %). CONCLUSIONS: Despite convincing data for the use of DES in patients with STEMI, there is still an underuse of DES in this clinical setting in Germany. This is particularly worrying for the subgroups of patients and lesions with a high risk of restenosis. Further efforts are needed to reduce the skepticism about DES and to improve guideline adherent treatment.