Randomized Comparisons Between Different Stenting Approaches for Bifurcation Coronary Lesions With or Without Side Branch Stenosis

ObjectivesThis study sought to evaluate the optimal percutaneous coronary intervention techniques using drug-eluting stents for bifurcation coronary lesions.BackgroundThe optimal bifurcation stenting technique needs to be evaluated.MethodsThe trial included 2 randomization studies separated by the presence of side branch (SB) stenosis for patients having non–left main bifurcation lesions. For 306 patients without SB stenosis, the routine final kissing balloon or leave-alone approaches were compared. Another randomization study compared the crush or single-stent approaches for 419 patients with SB stenosis.ResultsBetween the routine final kissing balloon and leave-alone groups for nondiseased SB lesions, angiographic restenosis occurred in 17.9% versus 9.3% (p = 0.064), comprising 15.1% versus 3.7% for the main branch (p = 0.004) and 2.8% versus 5.6% for the SB (p = 0.50) from 214 patients (69.9%) receiving 8-month angiographic follow-up. Incidence of major adverse cardiac events including death, myocardial infarction, or target vessel revascularization over 1 year was 14.0% versus 11.6% between the routine final kissing balloon and leave-alone groups (p = 0.57). In another randomization study for diseased SB lesions, 28.2% in the single-stent group received SB stents. From 300 patients (71.6%) receiving angiographic follow-up, between the crush and single-stent groups, angiographic restenosis rate was 8.4% versus 11.0% (p = 0.44), comprising 5.2% versus 4.8% for the main branch (p = 0.90) and 3.9% versus 8.3% for the SB (p = 0.12). One-year major adverse cardiac events rate between the crush and single-stent groups was 17.9% versus 18.5% (p = 0.84).ConclusionsAngiographic and clinical outcomes were excellent after percutaneous coronary intervention using drug-eluting stents with any stent technique for non–left main bifurcation lesions once the procedure was performed successfully.     

Impact of the Complexity of Bifurcation Lesions Treated With Drug-Eluting Stents: The DEFINITION Study (Definitions and impact of complEx biFurcation lesIons on clinical outcomes after percutaNeous coronary IntervenTIOn using drug-eluting steNts)

ObjectivesThe present study established criteria to differentiate simple from complex bifurcation lesions and compared 1-year outcomes stratified by lesion complexity after provisional stenting (PS) and 2-stent techniques using drug-eluting stents.BackgroundCurrently, no criterion can distinguish between simple and complex coronary bifurcation lesions. Comparisons of PS and 2-stent strategies stratified by lesion complexity have also not been reported previously.MethodsCriteria of bifurcation complexity in 1,500 patients were externally tested in another 3,660 true bifurcation lesions after placement of drug-eluting stents. The primary endpoint was the occurrence of a major adverse cardiac event (MACE) at 12 months. The secondary endpoint was the rate of stent thrombosis (ST).ResultsComplex (n = 1,108) bifurcation lesions were associated with a higher 1-year rate of MACE (16.8%) compared with simple (n = 2,552) bifurcation lesions (8.9%) (p < 0.001). The in-hospital ST and 1-year target lesion revascularization rates after 2-stent techniques in the simple group (1.0% and 5.6%, respectively) were significantly different from those after PS (0.2% [p = 0.007] and 3.2% [p = 0.009], respectively); however, 1-year MACE rates were not significantly different between the 2 groups. For complex bifurcation lesions, 2-stent techniques had lower rates of 1-year cardiac death (2.8%) and in-hospital MACE (5.0%) compared with PS (5.3%, p = 0.047; 8.4%, p = 0.031).ConclusionsComplex bifurcation lesions had higher rates of 1-year MACE and ST. The 2-stent and PS techniques were overall equivalent in 1-year MACE. However, 2-stent techniques for complex lesions elicited a lower rate of cardiac death and in-hospital MACE but higher rates of in-hospital ST and revascularization at 1 year for simple lesions.     

Comparative Analysis of Sequential Proximal Optimizing Technique Versus Kissing Balloon Inflation Technique in Provisional Bifurcation Stenting: Fractal Coronary Bifurcation Bench Test

ObjectivesThis study used a fractal bifurcation bench model to compare 6 optimization sequences for coronary bifurcation provisional stenting, including 1 novel sequence without kissing balloon inflation (KBI), comprising initial proximal optimizing technique (POT) + side-branch inflation (SBI) + final POT, called “re-POT.”BackgroundIn provisional bifurcation stenting, KBI fails to improve the rate of major adverse cardiac events. Proximal geometric deformation increases the rate of in-stent restenosis and target lesion revascularization.MethodsA bifurcation bench model was used to compare KBI alone, KBI after POT, KBI with asymmetric inflation pressure after POT, and 2 sequences without KBI: initial POT plus SBI, and initial POT plus SBI with final POT (called “re-POT”). For each protocol, 5 stents were tested using 2 different drug-eluting stent designs: that is, a total of 60 tests.ResultsCompared with the classic KBI-only sequence and those associating POT with modified KBI, the re-POT sequence gave significantly (p < 0.05) better geometric results: it reduced SB ostium stent-strut obstruction from 23.2 ± 6.0% to 5.6 ± 8.3%, provided perfect proximal stent apposition with almost perfect circularity (ellipticity index reduced from 1.23 ± 0.02 to 1.04 ± 0.01), reduced proximal area overstretch from 24.2 ± 7.6% to 8.0 ± 0.4%, and reduced global strut malapposition from 40 ± 6.2% to 2.6 ± 1.4%.ConclusionsIn comparison with 5 other techniques, the re-POT sequence significantly optimized the final result of provisional coronary bifurcation stenting, maintaining circular geometry while significantly reducing SB ostium strut obstruction and global strut malapposition. These experimental findings confirm that provisional stenting may be optimized more effectively without KBI using re-POT.     

Fractional Flow Reserve and Coronary Bifurcation Anatomy: A Novel Quantitative Model to Assess and Report the Stenosis Severity of Bifurcation Lesions

ObjectivesThe aim of this study was to develop a new model for assessment of stenosis severity in a bifurcation lesion including its core. The diagnostic performance of this model, powered by 3-dimensional quantitative coronary angiography to predict the functional significance of obstructive bifurcation stenoses, was evaluated using fractional flow reserve (FFR) as the reference standard.BackgroundDevelopment of advanced quantitative models might help to establish a relationship between bifurcation anatomy and FFR.MethodsPatients who had undergone coronary angiography and interventions in 5 European cardiology centers were randomly selected and analyzed. Different bifurcation fractal laws, including Murray, Finet, and HK laws, were implemented in the bifurcation model, resulting in different degrees of stenosis severity.ResultsA total of 78 bifurcation lesions in 73 patients were analyzed. In 51 (65%) bifurcations, FFR was measured in the main vessel. A total of 34 (43.6%) interrogated vessels had an FFR ≤0.80. Correlation between FFR and diameter stenosis was poor by conventional straight analysis (ρ = −0.23, p < 0.001) but significantly improved by bifurcation analyses: the highest by the HK law (ρ = −0.50, p < 0.001), followed by the Finet law (ρ = −0.49, p < 0.001), and the Murray law (ρ = −0.41, p < 0.001). The area under the receiver-operating characteristics curve for predicting FFR ≤0.80 was significantly higher by bifurcation analysis compared with straight analysis: 0.72 (95% confidence interval: 0.61 to 0.82) versus 0.60 (95% confidence interval: 0.49 to 0.71; p = 0.001). Applying a threshold of ≥50% diameter stenosis, as assessed by the bifurcation model, to predict FFR ≤0.80 resulted in 23 true positives, 27 true negatives, 17 false positives, and 11 false negatives.ConclusionsThe new bifurcation model provides a comprehensive assessment of bifurcation anatomy. Compared with straight analysis, identification of lesions with preserved FFR values in obstructive bifurcation stenoses was improved. Nevertheless, accuracy was limited by using solely anatomical parameters.     

Long-Term Clinical Outcomes of Final Kissing Ballooning in Coronary Bifurcation Lesions Treated With the 1-Stent Technique: Results From the COBIS II Registry (Korean Coronary Bifurcation Stenting Registry)

ObjectivesThis study investigated the impact of final kissing ballooning (FKB) after main vessel (MV) stenting on outcomes in patients with coronary bifurcation lesions after application of the 1-stent technique.BackgroundAlthough FKB has been established as the standard method for bifurcation lesions treated with a 2-stent strategy, its efficacy in a 1-stent approach is highly controversial.MethodsThis study enrolled 1,901 patients with a bifurcation lesion with a side branch diameter ≥2.3 mm, treated solely with the 1-stent technique using a drug-eluting stent from 18 centers in Korea between January 1, 2003 and December 31, 2009. The primary outcome was major adverse cardiac events (MACE)—cardiac death, myocardial infarction, or target lesion revascularization. Propensity score-matching analysis was also performed.ResultsFKB was performed in 620 patients and the post minimal lumen diameter of the MV and side branch was larger in the FKB group than in the non-FKB group. During follow-up (median 36 months), the incidence of MACE (adjusted hazard ratio [HR]: 0.68, 95% confidence interval [CI]: 0.46 to 0.99; p = 0.048) was lower in the FKB group than the non-FKB group. After propensity score matching (545 pairs), the FKB group had a lower incidence of MACE (adjusted HR: 0.50, 95% CI: 0.30 to 0.85; p = 0.01), and target lesion revascularization in the MV (adjusted HR: 0.51, 95% CI: 0.28 to 0.93; p = 0.03) and both vessels (adjusted HR: 0.47, 95% CI: 0.25 to 0.90; p = 0.02) than in the non-FKB group.ConclusionsIn coronary bifurcation lesions, we demonstrated that the 1-stent technique with FKB was associated with a favorable long-term clinical outcome, mainly driven by the reduction of target lesion revascularization in the MV or both vessels as a result of an increase in minimal lumen diameter. (Korean Coronary Bifurcation Stenting Registry II [COBIS II]: NCT01642992)     

Clinical Outcome After DK Crush Versus Culotte Stenting of Distal Left Main Bifurcation Lesions: The 3-Year Follow-Up Results of the DKCRUSH-III Study

ObjectivesThe present study aimed to investigate the difference in major adverse cardiac events (MACE) at 3 years after double-kissing (DK) crush versus culotte stenting for unprotected left main distal bifurcation lesions (LMDBLs).BackgroundThe multicenter and randomized DKCRUSH-III (Comparison of double kissing crush versus culotte stenting for unprotected distal left main bifurcation lesions: results from a multicenter, randomized, prospective study) showed that DK crush stenting was associated with fewer MACE at 1-year follow-up in patients with LMDBLs compared with culotte stenting. Here, we report the 3-year clinical outcome of the DKCRUSH-III study.MethodsA total of 419 patients with LMDBLs who were randomly assigned to either the DK crush or culotte group in the DKCRUSH-III study were followed for 3 year. The primary endpoint was the occurrence of a MACE at 3 years. Stent thrombosis (ST) was the safety endpoint. Patients were classified by simple and complex LMDBLs according to the DEFINITION (Definition and Impact of Complex Bifurcation Lesions on Clinical Outcomes After Percutaneous Coronary Intervention Using Drug-Eluting Stents) study criteria.ResultsAt 3 years, MACE occurred in 49 patients the culotte group and in 17 patients in the DK crush group (cumulative event rates of 23.7% and 8.2%, respectively; p < 0.001), mainly driven by increased myocardial infarction (8.2% vs. 3.4%, respectively; p = 0.037) and target-vessel revascularization (18.8% vs. 5.8%, respectively; p < 0.001) between groups. Definite ST rate was 3.4% in the culotte group and 0% in the DK crush group (p = 0.007). Complex LMDBLs were associated with a higher rate of MACE (35.3%) at 3 years compared with a rate of 8.1% in patients with simple LMDBLs (p < 0.001), with an extremely higher rate in the culotte group (51.5% vs. 15.1%, p < 0.001).ConclusionsCulotte stenting for LMDBLs was associated with significantly increased rates of MACE and ST. (Double Kissing [DK] Crush Versus Culotte Stenting for the Treatment of Unprotected Distal Left Main Bifurcation Lesions: DKCRUSH-III, a Multicenter Randomized Study Comparing Double-Stent Techniques; ChiCTR-TRC-11001877)     

The Impact of Downstream Coronary Stenosis on Fractional Flow Reserve Assessment of Intermediate Left Main Coronary Artery Disease: Human Validation

ObjectivesThe aim of this study was to determine the impact of downstream coronary stenosis in the left anterior descending coronary artery (LAD) or left circumflex coronary artery (LCx) on the assessment of fractional flow reserve (FFR) across an intermediate left main coronary artery (LMCA) stenosis in humans with the pressure wire positioned in the nondiseased downstream vessel.BackgroundAccurate assessment of intermediate LMCA disease is critical for guiding decisions regarding revascularization. In theory, FFR across an intermediate LMCA stenosis will be affected by downstream disease, even if the pressure wire is positioned in the nondiseased downstream vessel.MethodsAfter percutaneous coronary intervention of the LAD, LCx, or both, an intermediate LMCA stenosis was created with a deflated balloon catheter. FFR was measured in the LAD and LCx coronary arteries before and after creation of downstream stenosis by inflating an angioplasty balloon within the newly placed stent. The true FFR (FFR_true) of the LMCA, measured in the nondiseased downstream vessel in the absence of stenosis in the other vessel, was compared with the apparent FFR (FFR_app) measured in the presence of stenosis.ResultsIn 25 patients, 91 pairs of measurements were made, 71 with LAD stenosis and 20 with LCx stenosis. FFR_true of the LMCA was significantly lower than FFR_app (0.81 ± 0.08 vs. 0.83 ± 0.08, p < 0.001), although the numerical difference was small. This difference correlated with the severity of the downstream disease (r = 0.35, p < 0.001). In all cases in which FFR_app was >0.85, FFR_true was >0.80.ConclusionsIn most cases, downstream disease does not have a clinically significant impact on the assessment of FFR across an intermediate LMCA stenosis with the pressure wire positioned in the nondiseased vessel.     

Differential Prognostic Effect Between First- and Second-Generation Drug-Eluting Stents in Coronary Bifurcation Lesions: Patient-Level Analysis of the Korean Bifurcation Pooled Cohorts

ObjectivesThe purpose of this study was to investigate the differential clinical outcomes after percutaneous coronary intervention (PCI) for coronary bifurcation lesions with 1- or 2-stenting techniques using first- or second-generation drug-eluting stents (DES).BackgroundThe 2-stenting technique has been regarded to have worse clinical outcomes than the 1-stenting technique after bifurcation PCI with first-generation DES. However, there has been a paucity of data comparing the 1- and 2-stenting techniques with the use of second-generation DES.MethodsPatient-level pooled analysis was performed with 3,162 patients undergoing PCI using first- or second-generation DES for bifurcation lesions from the “Korean Bifurcation Pooled Cohorts” (COBIS [Coronary Bifurcation Stenting] II, EXCELLENT [Registry to Evaluate Efficacy of Xience/Promus Versus Cypher in Reducing Late Loss After Stenting], and RESOLUTE-Korea [Registry to Evaluate the Efficacy of Zotarolimus-Eluting Stent]). The 3-year clinical outcomes were compared between 1- and 2-stenting techniques, stratified by the type of DES.ResultsWith first-generation DES, rates of target lesion failure (TLF) or patient-oriented composite outcome (POCO) (a composite of all death, any myocardial infarction, any repeat revascularization, and cerebrovascular accidents) at 3 years were significantly higher after the 2-stenting than the 1-stenting technique (TLF 8.6% vs. 17.5%; p < 0.001; POCO 18.1% vs. 28.5%, p < 0.001). With second-generation DES, however, there was no difference between 1- and 2-stenting techniques (TLF 5.4% vs. 5.8%; p = 0.768; POCO 11.2% vs. 12.9%; p = 0.995). The differential effects of 2-stenting technique on the prognosis according to the type of DES were also corroborated with similar results by the inverse probability weighted model. The 2-stenting technique was a significant independent predictor of TLF in first-generation DES (hazard ratio: 2.046; 95% confidence interval: 1.114 to 3.759; p < 0.001), but not in second-generation DES (hazard ratio: 0.667; 95% confidence interval: 0.247 to 1.802; p = 0.425).ConclusionsPatient-level pooled analysis of 3,162 patients in Korean Bifurcation Pooled Cohorts demonstrated that the 2-stenting technique showed comparable outcomes to 1-stenting technique with second-generation DES, which is different from the results of first-generation DES favoring the 1-stenting technique.     

Prognostic Value of Fractional Flow Reserve: Linking Physiologic Severity to Clinical Outcomes

BackgroundFractional flow reserve (FFR) has become an established tool for guiding treatment, but its graded relationship to clinical outcomes as modulated by medical therapy versus revascularization remains unclear.ObjectivesThe study hypothesized that FFR displays a continuous relationship between its numeric value and prognosis, such that lower FFR values confer a higher risk and therefore receive larger absolute benefits from revascularization.MethodsMeta-analysis of study- and patient-level data investigated prognosis after FFR measurement. An interaction term between FFR and revascularization status allowed for an outcomes-based threshold.ResultsA total of 9,173 (study-level) and 6,961 (patient-level) lesions were included with a median follow-up of 16 and 14 months, respectively. Clinical events increased as FFR decreased, and revascularization showed larger net benefit for lower baseline FFR values. Outcomes-derived FFR thresholds generally occurred around the range 0.75 to 0.80, although limited due to confounding by indication. FFR measured immediately after stenting also showed an inverse relationship with prognosis (hazard ratio: 0.86, 95% confidence interval: 0.80 to 0.93; p < 0.001). An FFR-assisted strategy led to revascularization roughly half as often as an anatomy-based strategy, but with 20% fewer adverse events and 10% better angina relief.ConclusionsFFR demonstrates a continuous and independent relationship with subsequent outcomes, modulated by medical therapy versus revascularization. Lesions with lower FFR values receive larger absolute benefits from revascularization. Measurement of FFR immediately after stenting also shows an inverse gradient of risk, likely from residual diffuse disease. An FFR-guided revascularization strategy significantly reduces events and increases freedom from angina with fewer procedures than an anatomy-based strategy.     

Single String Technique for Coronary Bifurcation Stenting: Detailed Technical Evaluation and Feasibility Analysis

ObjectivesThe study aimed to evaluate the adequacy and feasibility of the single string bifurcation stenting technique.BackgroundDouble-stent techniques may be required for complex bifurcations. Currently applied methods all have their morphological or structural limitations with respect to wall coverage, multiple strut layers, and apposition rate.MethodsSingle string is a novel method in which, first, the side branch (SB) stent is deployed with a single stent cell protruding into the main branch (MB). Second, the MB stent is deployed across this protruding stent cell. The procedure is completed by final kissing balloon dilation. The single string technique was first tested in vitro (n = 20) and next applied in patients (n = 11) with complex bifurcation stenoses.ResultsAll procedures were performed successfully, crossing a single stent cell in 100%. Procedure duration was 23.0 ± 7.9 min, and the fluoroscopy time was 9.4 ± 3.5 min. The results were evaluated by optical coherence tomography, showing fully apposed struts in 83.0 ± 9.2% in the bifurcation area. Residual area obstruction in the MB was 6.4 ± 5.6% and 25.0 ± 16.9% in the SB, as evaluated by micro computed tomography. All the human cases were performed successfully with excellent angiographic results: the residual area stenosis was 27 ± 8% and 29 ± 10% in the MB and in the SB, respectively, by 3-dimensional quantitative coronary angiography. No relevant periprocedural enzyme increase was observed. During follow-up (6 ± 4 months), no adverse clinical events (death, myocardial infarction, target vessel revascularization) were noted.ConclusionsThe single string technique for complex bifurcation dilation was shown to be adequate in vitro and feasible in humans, with favorable results in terms of stent overlap, malapposition rate, and low residual obstruction in both the MB and SB.     

Coronary Vessel Wall Contrast Enhancement Imaging as a Potential Direct Marker of Coronary Involvement: Integration of Findings From CAD and SLE Patients

ObjectivesThis study investigated the feasibility of visual and quantitative assessment of coronary vessel wall contrast enhancement (CE) for detection of symptomatic atherosclerotic coronary artery disease (CAD) and subclinical coronary vasculitis in autoimmune inflammatory disease (systemic lupus erythematosus [SLE]), as well as the association with aortic stiffness, an established marker of risk.BackgroundCoronary CE by cardiac magnetic resonance (CMR) is a novel noninvasive approach to visualize gadolinium contrast uptake within the coronary artery vessel wall.MethodsA total of 75 subjects (CAD: n = 25; SLE: n = 27; control: n = 23) underwent CMR imaging using a 3-T clinical scanner. Coronary arteries were visualized by a T2-prepared steady state free precession technique. Coronary wall CE was visualized using inversion-recovery T1 weighted gradient echo sequence 40 min after administration of 0.2 mmol/kg gadobutrol. Proximal coronary segments were visually examined for distribution of CE and quantified for contrast-to-noise ratio (CNR) and total CE area.ResultsCoronary CE was prevalent in patients (93%, n = 42) with a diffuse pattern for SLE and a patchy/regional distribution in CAD patients. Compared with control subjects, CNR values and total CE area in patients with CAD and SLE were significantly higher (mean CNR: 3.9 ± 2.5 vs. 6.9 ± 2.5 vs. 6.8 ± 2.0, respectively; p < 0.001; total CE area: median 0.8 [interquartile range (IQR): 0.6 to 1.2] vs. 3.2 [IQR: 2.6 to 4.0] vs. 3.3 [IQR: 1.9 to 4.5], respectively; p < 0.001). Both measures were positively associated with aortic stiffness (CNR: r = 0.61, p < 0.01; total CE area: 0.36, p = 0.03), hypercholesterolemia (r = 0.68, p < 0.001; r = 0.61, p < 0.001) and hypertension (r = 0.40, p < 0.01; r = 0.32, p < 0.05).ConclusionsWe demonstrate that quantification of coronary CE by CNR and total CE area is feasible for detection of subclinical and clinical uptake of gadolinium within the coronary vessel wall. Coronary vessel wall CE may become an instrumental novel direct marker of vessel wall injury and remodeling in subpopulations at risk.     

Outcomes After Percutaneous Coronary Intervention With Stents in Patients Treated With Thoracic External Beam Radiation for Cancer

ObjectivesThe aim of this study was to assess outcomes after percutaneous coronary intervention (PCI) with stents in patients treated with thoracic external beam radiation therapy (EBRT).BackgroundThoracic EBRT for cancer is associated with long-term cardiotoxic sequelae. The impact of EBRT on patients requiring coronary stents is unclear.MethodsWe analyzed outcomes after PCI in cancer survivors treated with curative thoracic EBRT before and after stenting between 1998 and 2012. Reference groups were propensity-matched cohorts with stenting but no EBRT. Primary endpoint was target lesion revascularization (TLR), a clinical surrogate for restenosis. Secondary endpoints included myocardial infarction (MI) and cardiac and overall mortality.ResultsWe identified 115 patients treated with EBRT a median 3.6 years after stenting (group A) and 45 patients treated with EBRT a median 2.2 years before stenting (group B). Long-term mean TLR rates in group A (3.2 vs. 6.6%; hazard ratio: 0.6; 95% confidence interval: 0.2 to 1.6; p = 0.31) and group B (9.2 vs. 9.7%; hazard ratio: 1.2; 95% confidence interval: 0.4 to 3.4; p = 0.79) were similar to rates in corresponding control patients (group A: 1,390 control patients; group B: 439 control patients). Three years post-PCI, group A had higher overall mortality (48.6% vs. 13.9%; p < 0.001) but not MI (4.8% vs. 4.3%; p = 0.93) or cardiac mortality (2.3% vs. 3.6%; p = 0.66) rates versus control patients. There were no significant differences in MI, cardiac, or overall mortality rates in group B.ConclusionsThoracic EBRT is not associated with increased stent failure rates when used before or after PCI. A history of PCI should not preclude the use of curative thoracic EBRT in cancer patients or vice versa. Optimal treatment of cancer should be the goal.     

Outcomes of Comatose Cardiac Arrest Survivors With and Without ST-Segment Elevation Myocardial Infarction: Importance of Coronary Angiography

ObjectivesThe aim of this study was to compare outcomes and coronary angiographic findings in post–cardiac arrest patients with and without ST-segment elevation myocardial infarction (STEMI).BackgroundThe 2013 STEMI guidelines recommend performing immediate angiography in resuscitated patients whose initial electrocardiogram shows STEMI. The optimal approach for those without STEMI post–cardiac arrest is less clear.MethodsA retrospective evaluation of a post–cardiac arrest registry was performed.ResultsThe database consisted of 746 comatose post–cardiac arrest patients including 198 with STEMI (26.5%) and 548 without STEMI (73.5%). Overall survival was greater in those with STEMI compared with those without (55.1% vs. 41.3%; p = 0.001), whereas in all patients who underwent immediate coronary angiography, survival was similar between those with and without STEMI (54.7% vs. 57.9%; p = 0.60). A culprit vessel was more frequently identified in those with STEMI, but also in one-third of patients without STEMI (80.2% vs. 33.2%; p = 0.001). The majority of culprit vessels were occluded (STEMI, 92.7%; no STEMI, 69.2%; p < 0.0001). An occluded culprit vessel was found in 74.3% of STEMI patients and in 22.9% of no STEMI patients. Among cardiac arrest survivors discharged from the hospital who had presented without STEMI, coronary angiography was associated with better functional outcome (93.3% vs. 78.7%; p < 0.003).ConclusionsEarly coronary angiography is associated with improved functional outcome among resuscitated patients with and without STEMI. Resuscitated patients with a presumed cardiac etiology appear to benefit from immediate coronary angiography.     

Intravascular Ultrasound-Derived Minimal Lumen Area Criteria for Functionally Significant Left Main Coronary Artery Stenosis

ObjectivesThis study sought to evaluate the intravascular ultrasound (IVUS) minimal lumen area (MLA) for functionally significant left main coronary artery (LMCA) stenosis using fractional flow reserve (FFR) as the standard.BackgroundThe evaluation of significant LMCA stenosis remains challenging.MethodsWe identified 112 patients with isolated ostial and shaft intermediate LMCA stenosis (angiographic diameter stenosis of 30% to 80%) who underwent IVUS and FFR measurement.ResultsThe FFR was ≤0.80 in 66 LMCA lesions (59%); these exhibited smaller reference vessels, smaller minimal lumen diameter, greater diameter of stenosis, longer lesion length, smaller MLA, larger plaque burden, and more frequent plaque rupture. The independent factors of an FFR of ≤0.80 were plaque rupture (odds ratio [OR]: 4.47; 95% Confidence Interval (CI): 1.35 to 14.8; p = 0.014); body mass index (OR: 1.19; 95% CI: 1.00 to 1.41; p = 0.05), age (OR: 0.95; 95% CI: 0.90 to 1.00; p = 0.031), and IVUS MLA (OR: 0.37; 95% CI: 0.25 to 0.56; p < 0.001). The optimal IVUS MLA cutoff value for an FFR of ≤0.80 was 4.5 mm² (77% sensitivity, 82% specificity, 84% positive predictive value, 75% negative predictive value, area under the curve: 0.83, 95% CI: 0.76 to 0.96; p < 0.001) overall and 4.1 to 4.5 mm² in various subgroups. Adjustment for the body surface area, body mass index, and left ventricular mass did not improve the diagnostic accuracy of the IVUS MLA.ConclusionsIn patients with isolated ostial and shaft intermediate LMCA stenosis, an IVUS-derived MLA of ≤4.5 mm² is a useful index of an FFR of ≤0.80.     

Pre-Angioplasty Instantaneous Wave-Free Ratio Pullback Provides Virtual Intervention and Predicts Hemodynamic Outcome for Serial Lesions and Diffuse Coronary Artery Disease

ObjectivesThe aim of this study was to perform hemodynamic mapping of the entire vessel using motorized pullback of a pressure guidewire with continuous instantaneous wave-free ratio (iFR) measurement.BackgroundSerial stenoses or diffuse vessel narrowing hamper pressure wire–guided management of coronary stenoses. Characterization of functional relevance of individual stenoses or narrowed segments constitutes an unmet need in ischemia-driven percutaneous revascularization.MethodsThe study was performed in 32 coronary arteries with tandem and/or diffusely diseased vessels. An automated iFR physiological map, integrating pullback speed and physiological information, was built using dedicated software to calculate physiological stenosis severity, length, and intensity (ΔiFR/mm). This map was used to predict the best-case post–percutaneous coronary intervention (PCI) iFR (iFR_exp) according to the stented location, and this was compared with the observed iFR post-PCI (iFR_obs).ResultsAfter successful PCI, the mean difference between iFR_exp and iFR_obs was small (mean difference: 0.016 ± 0.004) with a strong relationship between ΔiFR_exp and ΔiFR_obs (r = 0.97, p < 0.001). By identifying differing iFR intensities, it was possible to identify functional stenosis length and quantify the contribution of each individual stenosis or narrowed segment to overall vessel stenotic burden. Physiological lesion length was shorter than anatomic length (12.6 ± 1.5 vs. 23.3 ± 1.3, p < 0.001), and targeting regions with the highest iFR intensity predicted significant improvement post-PCI (r = 0.86, p < 0.001).ConclusionsiFR measurements during continuous resting pressure wire pullback provide a physiological map of the entire coronary vessel. Before a PCI, the iFR pullback can predict the hemodynamic consequences of stenting specific stenoses and thereby may facilitate the intervention and stenting strategy.     

Repeatability of Fractional Flow Reserve Despite Variations in Systemic and Coronary Hemodynamics

ObjectivesThis study classified and quantified the variation in fractional flow reserve (FFR) due to fluctuations in systemic and coronary hemodynamics during intravenous adenosine infusion.BackgroundAlthough FFR has become a key invasive tool to guide treatment, questions remain regarding its repeatability and stability during intravenous adenosine infusion because of systemic effects that can alter driving pressure and heart rate.MethodsWe reanalyzed data from the VERIFY (VERification of Instantaneous Wave-Free Ratio and Fractional Flow Reserve for the Assessment of Coronary Artery Stenosis Severity in EverydaY Practice) study, which enrolled consecutive patients who were infused with intravenous adenosine at 140 μg/kg/min and measured FFR twice. Raw phasic pressure tracings from the aorta (Pa) and distal coronary artery (Pd) were transformed into moving averages of Pd/Pa. Visual analysis grouped Pd/Pa curves into patterns of similar response. Quantitative analysis of the Pd/Pa curves identified the “smart minimum” FFR using a novel algorithm, which was compared with human core laboratory analysis.ResultsA total of 190 complete pairs came from 206 patients after exclusions. Visual analysis revealed 3 Pd/Pa patterns: “classic” (sigmoid) in 57%, “humped” (sigmoid with superimposed bumps of varying height) in 39%, and “unusual” (no pattern) in 4%. The Pd/Pa pattern repeated itself in 67% of patient pairs. Despite variability of Pd/Pa during the hyperemic period, the “smart minimum” FFR demonstrated excellent repeatability (bias −0.001, SD 0.018, paired p = 0.93, r² = 98.2%, coefficient of variation = 2.5%). Our algorithm produced FFR values not significantly different from human core laboratory analysis (paired p = 0.43 vs. VERIFY; p = 0.34 vs. RESOLVE).ConclusionsIntravenous adenosine produced 3 general patterns of Pd/Pa response, with associated variability in aortic and coronary pressure and heart rate during the hyperemic period. Nevertheless, FFR – when chosen appropriately – proved to be a highly reproducible value. Therefore, operators can confidently select the “smart minimum” FFR for patient care. Our results suggest that this selection process can be automated, yet comparable to human core laboratory analysis.     

Hybrid Revascularization for Multivessel Coronary Artery Disease

ObjectivesThe aim of this study was to assess the feasibility of hybrid coronary revascularization (HCR) in patients with multivessel coronary artery disease (MVCAD) referred for standard coronary artery bypass grafting (CABG).BackgroundConventional CABG is still the treatment of choice in patients with MVCAD. However, the limitations of standard CABG and the unsatisfactory long-term patency of saphenous grafts are commonly known.MethodsA total of 200 patients with MVCAD involving the left anterior descending artery (LAD) and a critical (>70%) lesion in at least 1 major epicardial vessel (except the LAD) amenable to both PCI and CABG and referred for conventional surgical revascularization were randomly assigned to undergo HCR or CABG (in a 1:1 ratio). The primary endpoint was the evaluation of the safety of HCR. The feasibility was defined by the percent of patients with a complete HCR procedure and the percent of patients with conversions to standard CABG. The occurrence of major adverse cardiac events such as death, myocardial infarction, stroke, repeated revascularization, and major bleeding within the 12-month period after randomization was also assessed.ResultsMost of the pre-procedural characteristics were similar in the 2 groups. Of the patients in the hybrid group, 93.9% had complete HCR and 6.1% patients were converted to standard CABG. At 12 months, the rates of death (2.0% vs. 2.9 %, p = NS), myocardial infarction (6.1% vs. 3.9%, p = NS), major bleeding (2% vs. 2%, p = NS), and repeat revascularization (2% vs. 0%, p = NS) were similar in the 2 groups. In both groups, no cerebrovascular incidents were observed.ConclusionsHCR is feasible in select patients with MVCAD referred for conventional CABG. (Safety and Efficacy Study of Hybrid Revascularization in Multivessel Coronary Artery Disease [POL-MIDES]; NCT01035567).     

Outcomes of Primary Percutaneous Coronary Intervention in ST-Segment Elevation Myocardial Infarction Patients With Previous Coronary Bypass Surgery

ObjectivesThis study sought to determine the contemporary clinical characteristics and outcomes of patients with ST-segment elevation myocardial infarction (STEMI) and previous coronary artery bypass graft (CABG), including those with a saphenous vein graft culprit lesion.BackgroundThe outcome of STEMI patients with previous CABG is reported to be inferior to those without previous CABG, but limited data is available from the primary percutaneous coronary intervention era.MethodsData was extracted from a large, regional STEMI system’s prospective database, which contained 3,542 unique STEMI episodes from March 4, 2003 through April 22, 2012.ResultsPrevious CABG was present in 249 patients (7%). Despite higher comorbidity, patients with versus those without previous CABG had similar in-hospital (4.8% vs. 5.2%; p = 0.82) and 1-year (10.8% vs. 9.1%; p = 0.36) mortality, but 5-year (24.9% vs. 14.2%; p < 0.001) mortality was higher. Patients with previous CABG have similar door-to-balloon times. The culprit vessel was the saphenous vein graft in 84 patients (34%), a native vessel in 104 (42%), with no clear culprit in 59 (24%). The left internal mammary artery graft was not a culprit in any patient. Mortality at 30 days (8.3% vs. 3.9% vs. 1.7%, p = 0.19) and 1 year (14.3% vs. 9.0% vs. 6.8%; p = 0.35) was higher (but not statistically) with a saphenous vein graft culprit and was equivalent at 5 years (25.0% vs. 26.0% vs. 20.3%; p = 0.71).ConclusionsPatients with previous CABG treated in a regional STEMI system have similar outcomes as patients without previous CABG, although 5-year mortality is higher. The most common culprit location was a native vessel (42%). Outcomes have improved significantly compared with historical reports.     

A Randomized Comparison of Novel Biodegradable Polymer- and Durable Polymer–Coated Cobalt-Chromium Sirolimus-Eluting Stents

ObjectivesThe aim of this study was to investigate the hypothesis that a novel biodegradable polymer–coated, cobalt-chromium (CoCr), sirolimus-eluting stent (BP-SES) is noninferior in safety and efficacy outcomes compared with a durable polymer (DP)-SES.BackgroundNo randomized trials have the compared safety and efficacy of BP-SES versus DP-SES on similar CoCr platforms, thereby isolating the effect of the polymer type.MethodsIn this prospective, single-blind, randomized trial conducted at 32 Chinese sites, 2,737 patients eligible for coronary stenting were treated with BP- or DP-SES in a 2:1 ratio. The primary endpoint was 12-month target lesion failure (TLF), a composite of cardiac death, target vessel myocardial infarction, or clinically indicated target lesion revascularization. Secondary endpoints included TLF components, and definite/probable stent thrombosis.ResultsAt 12 months, the difference in the primary endpoint of TLF between BP-SES (6.3%) and DP-SES (6.1%) groups was 0.25% (95% confidence interval: −1.67% to 2.17%, p for noninferiority = 0.0002), demonstrating noninferiority of BP-SES to DP-SES. Individual TLF components of cardiac death (0.7% vs. 0.6%, p = 0.62), target vessel myocardial infarction (3.6% vs. 4.3%, p = 0.39), and clinically indicated target lesion revascularization (2.6% vs. 2.2%, p = 0.50) were similar, as were low definite/probable stent thrombosis rates (0.4% vs. 0.6%, p = 0.55).ConclusionsIn this large-scale real-world trial, BP-SES was noninferior to DP-SES for 1-year TLF. (Evaluate Safety and Effectiveness of the Tivoli ® DES and the Firebird ® DES for Treatment of Coronary Revascularization; NCT01681381)     

Effect of Drug-Coated Balloons in Native Coronary Artery Disease Left With a Dissection

ObjectivesThe authors sought to understand the clinical and angiographic outcomes of dissections left after drug-coated balloon (DCB) angioplasty.BackgroundSecond-generation DCB may be an alternative to stents in selected populations for the treatment of native coronary lesions. However, the use of these devices may be hampered by a certain risk of acute vessel recoil or residual coronary dissection. Moreover, stenting after DCB has shown limited efficacy. Little is known about when a non–flow-limiting dissection is left after DCB angioplasty.MethodsThis was a prospective observational study whose aim was to investigate the outcome of a consecutive series of patients with native coronary artery disease treated with second-generation DCB and residual coronary dissection at 2 Italian centers. We evaluated patient clinical conditions at 1 and 9 months, and angiographic follow up was undertaken at 6 months.ResultsBetween July 2012 and July 2014, 156 patients were treated with DCB for native coronary artery disease. Fifty-two patients had a final dissection, 4 of which underwent prosthesis implantation and 48 were left untreated and underwent angiographic follow-up after 201 days (interquartile range: 161 to 250 days). The dissections were all type A to C, and none determined an impaired distal flow. Complete vessel healing at angiography was observed in 45 patients (93.8%), whereas 3 patients had persistent but uncomplicated dissections, and 3 had binary restenosis (6.2%). Late lumen loss was 0.14 mm (−0.14 to 0.42). Major adverse cardiovascular events occurred in 11 patients in the entire cohort and in 4 of the dissection cohort (7.2% vs. 8.1%; p = 0.48). We observed 8 and 3 target lesion revascularizations, respectively (5.3% vs. 6.2%; p = 0.37).ConclusionsIn this cohort of consecutive patients treated with new-generation DCB and left with a final dissection, this strategy of revascularization seemed associated with the sealing of most of dissections and without significant neointimal hyperplasia.