Relation of percutaneous coronary intervention of complex lesions to clinical outcomes (from the NHLBI Dynamic Registry)

Recent Advances in Antiplatelet Therapy in Complex Percutaneous Coronary Intervention

Antithrombotic therapy is the cornerstone of secondary cardiovascular prevention after percutaneous coronary intervention (PCI). Improvements in drug-eluting stent (DES) design and materials over the last 2 decades have prompted the development of new antithrombotic strategies. Current guidelines recommend to tailor dual antiplatelet therapy (DAPT) according to clinical presentation and individual ischemic and bleeding risk. Given the growing number of complex PCI procedures performed nowadays, it is a priority to define the optimal antithrombotic treatment in this challenging patient subset. In this review article, we sought to summarize and discuss the current evidence on antiplatelet therapy in patients undergoing complex PCI.

Periprocedural Antithrombotic Treatment in Complex Percutaneous Coronary Intervention

ABSTRACT

In recent years, the management of complex lesions in patients undergoing percutaneous coronary intervention (PCI) constitutes a field of high interest and concern for the interventional cardiology. As more and more studies demonstrate the increased hazard of ischemic events in this group of patients, it is of paramount importance for the physicians to choose the optimal periprocedural (pre-PCI, during-PCI and post-PCI) antithrombotic treatment strategies wisely. Evidence regarding the safety and efficacy of current anticoagulation recommendation, the possible beneficial role of the pretreatment with a potent P2Y12 inhibitor in the subgroup of patients with non-ST segment elevation myocardial infarction with complex lesions, and the impact of a more potent P2Y12 inhibitor in individuals with stable coronary artery disease undergoing complex PCI are needed. This will provide and serve as a guide to clinicians to deploy the maximum efficacy of the current choices of antithrombotic therapy, which will lead to an optimal balance between safety and efficacy in this demanding clinical scenario.

Antithrombotics in Complex Percutaneous Coronary Interventions: Type and Duration of Treatment

Patients undergoing complex percutaneous coronary intervention (PCI) are at an increased risk of atherothrombotic complications. Although dual antiplatelet therapy is the mainstay of treatment for patients undergoing PCI with stent implantation, deciding its type and duration in complex PCI patients has long been considered a challenge for clinicians. This is because the beneficial effects of prolonged treatment and/or more potent antiplatelet agents’ use in preventing ischemic events are hindered by a concomitant increase in bleeding complications. The aim of this review is to highlight current evidence regarding the optimal antithrombotic therapy regimens used in complex PCI patients, focusing on the evaluation of both safety and efficacy outcomes as well as addressing future perspectives.

Platelet Function Testing and Genotyping for Tailoring Treatment in Complex PCI Patients

Dual antiplatelet therapy (DAPT), comprising aspirin and a P2Y12 receptor inhibitor, is considered the cornerstone of treatment in patients who have undergone percutaneous coronary intervention (PCI). Patients with complex PCI (C-PCI) constitute a special PCI subpopulation, characterized by increased ischemic risk. Identifying the optimal DAPT strategy is often challenging and remains controversial in this setting. In an attempt to balance ischemic and bleeding risks in C-PCI patients receiving DAPT, treatment individualization regarding potency and duration has evolved as a feasible approach. Platelet function testing and genotyping have been evaluated in several trials with conflicting and mostly neutral results. The aim of this review is to critically appreciate the role of these tools for antiplatelet treatment tailoring specifically in C-PCI patients. Because existing evidence is limited, dedicated future studies are warranted to elucidate the utility of platelet function testing and genotyping in C-PCI.

The role of intravascular ultrasound in percutaneous coronary intervention of complex coronary lesions

Intravascular ultrasound (IVUS) is a catheter-based coronary imaging technique. It utilises the emission & subsequent detection of reflected high frequency (30-60 MHz) sound waves to create high resolution, cross-sectional images of the coronary artery. IVUS has been the cornerstone of intracoronary imaging for more than two decades. When compared to the invasive coronary angiogram which studies only the silhouette of the contrast-filled artery lumen, IVUS also crucially images the vessel wall. Because of this capability, IVUS has greatly facilitated understanding of the coronary atherosclerosis process. Such insights from IVUS reveal how commonly and extensively plain angiography underestimates the true extent of coronary plaque, the characteristics of plaques prone to rupture and cause acute coronary syndromes (lipid rich, thin cap atheroma), and a realisation of the widespread occurrence of vessel remodelling in response to atherosclerosis. Similarly, IVUS has historically provided salutary mechanistic insights that have guided many of the incremental advances in the techniques of percutaneous coronary intervention (PCI). Examples include mechanisms of in-stent restenosis, and the importance of high-pressure post-dilatation of stents to ensure adequate stent apposition and thereby reduce the occurrence of stent thrombosis. IVUS also greatly facilitates the choice of correct diameter and length of stent to implant. Overall, a compelling body of evidence indicates that use of intravascular ultrasound in PCI helps to achieve optimal technical results and to mitigate the risk of adverse cardiac events. In this review, the role of intravascular ultrasound as an adjunct to PCI in complex coronary lesions is explored. The complex coronary situations discussed are the left main stem, ostial stenoses, bifurcation stenoses, thrombotic lesions, the chronically occluded coronary artery, and calcified coronary artery disease. By thorough review of the available evidence, we establish that the advantages of IVUS guidance are particularly evident in each of these complex CAD subsets. In particular, some consider the use of IVUS to be almost mandatory in left main PCI. A comparison with other intracoronary imaging techniques is also explored.

Type and Duration of Dual Antiplatelet Therapy in Complex Percutaneous Coronary Intervention

Complex percutaneous coronary intervention (PCI) patients are a high-risk population for ischemic complications. Antiplatelet therapy in such patients remains controversial, as the beneficial effects of more potent agents use or prolonged dual antiplatelet treatment (DAPT) on atherothrombotic complications are hindered by a concomitant increase in bleeding rates. The aim of this article is to describe ischemic and bleeding outcomes associated with complex PCI procedures and to compare different types and durations of DAPT regimens in terms of safety and efficacy outcomes. Issues concerning special patient groups, such as those with left main, chronic total occlusion, or bifurcation lesions, are discussed.

Mid-term Clinical Outcomes of Immediate Protamine Use Following Elective Percutaneous Coronary Interventions

Bleeding complication has been considered as a serious problem in current percutaneous coronary interventions (PCI). Fortunately, several groups have already reported the effectiveness of protamine use just after PCI to immediately remove any arterial sheath. However, there is a concern that protamine reversal may increase non-occlusive thrombus and, in turn, lead to mid-term cardiovascular events such as target vessel revascularization (TVR) or stent thrombosis. Thus, the purpose of this study was to evaluate whether protamine use following elective PCI was associated with mid-term clinical outcomes. In total, 472 patients were included in this study; subsequently, they were divided into protamine group (n = 142) and non-protamine group (n = 330). The primary endpoint was the composite of ischemia-driven TVR and stent thrombosis. The median follow-up period was determined to be at 562 days. In total, 32 primary endpoints were observed during the study period, and the incidence of primary endpoints tended to be greater in the protamine group than in the non-protamine group (P = 0.056). However, the lesion length, the degree of calcification, and the prevalence of hemodialysis were significantly determined greater in the protamine group than in the non-protamine group. In the multivariate Cox proportional hazards model, the use of protamine (versus non-protamine: hazard ratio 0.542 and 95% confidence interval 0.217-1.355, P = 0.191) was deemed not to be associated with the primary endpoint after controlling legion length, calcification, and hemodialysis. In conclusion, immediate protamine use following elective PCI did not increase mid-term ischemia-driven TVR or stent thrombosis. However, immediate protamine use after PCI should be discussed further for the safety of the patient.

Tailoring Dual Antiplatelet Therapy for the Complex PCI Patient: Current Status and Perspectives

Dual antiplatelet therapy (DAPT) duration in patients undergoing percutaneous coronary intervention (PCI) has long been considered a matter of controversy. Complex-PCI (C-PCI) is considered to be associated with an increased ischemic risk that tends to be greater with progressively higher procedural complexity. Thus, with a view to balance ischemic versus bleeding risks, high complexity of PCI intuitively represents an advocate of prolonged DAPT duration. However, the optimal DAPT strategy in this high ischemic risk subset of patients remains unclear, a fact that is exacerbated by the absence of a universal definition of C-PCI, resulting in a significant between-study heterogeneity. The aim of this review is to highlight the increased risks associated with C-PCI, compare long- versus short-term DAPT regimens regarding safety and efficacy endpoints as well as investigate outcomes in special C-PCI cohorts, such as patients with bifurcation, left main or chronic total occlusion lesions. Furthermore, controversial issues, such as antithrombotic regimens in C-PCI patients with atrial fibrillation, and future perspectives are addressed.

Intravascular ultrasound versus angiography-guided drug-eluting stent implantation in patients with complex coronary lesions: An updated meta-analysis of nine randomized clinical trials

Objective:

Intravascular ultrasound (IVUS) is not routinely performed in the real-world practice, and the benefits of IVUS-guided drug-eluting stent (DES) implantation in patients with complex coronary lesions remains unclear. This updated meta-analysis attempts to evaluate the clinical outcomes of the IVUS guidance in these patients.

Methods:

We searched potential eligible citations from the PubMed, EMBASE, Medline, and other internet sources. The primary endpoint were major adverse cardiovascular events (MACE), including cardiac death, myocardial infarction (MI), and target vessel revascularization (TVR). The risk of definite/probable stent thrombosis (ST) was chosen as the safety endpoint.

Results:

Nine randomized trials including a total of 3,612 patients with complex coronary lesions were finally analyzed. Compared to angiography guidance, IVUS-guided DES implantation was associated with significantly lower incidence of MACE [odds ratios (OR) 0.57, 95% confidence intervals (CI): 0.45–0.72, p<0.001; I²=0.0%, p=0.674], cardiac death (OR 0.42, 95%CI:0.21–0.82, p=0.010; I²=0.0%, p=0.961), MI (OR 0.65, 95%CI:0.44–0.95, p=0.027; I²=41.8%, p=0.089), TVR (OR 0.55, 95%CI:0.38–0.79, p=0.001; I²=0.0%, p=0.916), target lesion revascularization (TLR) (OR 0.58, 95%CI:0.41–0.82, p=0.002; I²=0.0%, p=0.888), and ST (OR 0.48, 95%CI:0.24–0.93, p=0.029; I²=0.0%, p=0.733).

Conclusion:

The updated meta-analysis demonstrates that DES implantation under IVUS guidance leads to a significant reduction in MACE, cardiac death, MI, TVR, TLR, and ST among patients with complex coronary lesions.

A rare Case of "Acute Take Off" of Left Circumflex Artery Successfully Intervened using Dual-Lumen Microcatheter

“Acute take off” of the left circumflex artery (LCX) is a rare coronary artery variant. Development of coronary artery disease in such a vessel increases technical difficulty and failure rate for percutaneous coronary intervention. We report a rare case of “acute take off” of the LCX with proximal critical stenosis successfully intervened using dual-lumen microcatheter.

Impact of catheter-induced iatrogenic coronary artery dissection with or without postprocedural flow impairment: A report from a Japanese multicenter percutaneous coronary intervention registry

Despite the ever-increasing complexity of percutaneous coronary intervention (PCI), the incidence, predictors, and in-hospital outcomes of catheter-induced coronary artery dissection (CICAD) is not well defined. In addition, there are little data on whether persistent coronary flow impairment after CICAD will affect clinical outcomes. We evaluated 17,225 patients from 15 participating hospitals within the Japanese PCI registry from January 2008 to March 2016. Associations between CICAD and in-hospital adverse cardiovascular events were evaluated using multivariate logistic regression. Outcomes of patients with CICAD with or without postprocedural flow impairment (TIMI flow ≤ 2 or 3, respectively) were analyzed. The population was predominantly male (79.4%; mean age, 68.2 ± 11.0 years); 35.6% underwent PCI for complex lesions (eg. chronic total occlusion or a bifurcation lesion.). CICAD occurred in 185 (1.1%), and its incidence gradually decreased (p < 0.001 for trend); postprocedural flow impairment was observed in 43 (23.2%). Female sex, complex PCI, and target lesion in proximal vessel were independent predictors (odds ratio [OR], 2.18; 95% confidence interval [CI], 1.53–3.10; OR, 2.19; 95% CI, 1.58–3.04; and OR, 1.55; 95% CI, 1.06–2.28, respectively). CICAD was associated with an increased risk of in-hospital adverse events (composite of new-onset cardiogenic shock and new-onset heart failure) regardless of postprocedural flow impairment (OR, 10.9; 95% CI, 5.30–22.6 and OR, 2.27; 95% CI, 1.20–4.27, respectively for flow-impaired and flow-recovered CICAD). In conclusion, CICAD occurred in roughly 1% of PCI cases; female sex, complex PCI, and proximal lesion were its independent risk factors. CICAD was associated with adverse in-hospital cardiovascular events regardless of final flow status. Our data implied that the appropriate selection of PCI was necessary for women with complex lesions.

Percutaneous Left Main Coronary Intervention: A Review of Plaque Modification in Left Main Percutaneous Coronary Intervention

Left main coronary artery (LMCA) stenosis has long been recognized as a marker of increased morbidity and mortality. Current treatment algorithms for LMCA stenosis consider both percutaneous coronary intervention (PCI) with drug eluting stents (DES) and coronary bypass surgery, each with advantages based on individual patient characteristics. Since the LMCA is the largest artery in the coronary tree, plaque volume and calcification is greater than other coronary segments and often extends to the distal bifurcation segment. In LMCA bifurcation lesions, larger minimal stent area is strongly associated with better outcome in the DES era. Plaque modification strategies such as rotational, orbital, or laser atherectomy are effective mechanisms to reduce plaque volume and alter compliance, facilitating stent delivery and stent expansion. We present a case of a calcified, medina class 1,1,1 LMCA lesion where intravascular ultrasound (IVUS) and orbital atherectomy were employed for optimal results. In this context, we review the evidence of plaque modification devices and the rationale for their use in unprotected left main PCI.

Benefit of Prolonged Dual Antiplatelet Therapy After Implantation of Drug-Eluting Stent for Coronary Bifurcation Lesions

Background:

Whether prolonged dual antiplatelet therapy (DAPT) improves clinical outcomes after percutaneous coronary intervention for coronary bifurcation lesion is uncertain.

Methods and Results:

We evaluated 2082 patients who were treated with drug-eluting stent for bifurcation lesions and were event free (no death, myocardial infarction [MI], cerebrovascular accident, stent thrombosis, or any revascularization) at 12 months after the index procedure. Patients were divided into 2 groups: DAPT ≥12-month group (n=1776) and DAPT <12-month group (n=306). Primary outcome was all-cause death or MI. At 4 years after the index procedure, death or MI occurred less frequently in the DAPT ≥12-month group than the DAPT <12-month group (2.8% versus 12.3%; adjusted hazard ratio, 0.21; 95% confidence interval, 0.13–0.35; P <0.001). After propensity score matching, incidence of death or MI was still lower in the DAPT ≥12-month group than the DAPT <12-month group (2.6% versus 12.3%; adjusted hazard ratio, 0.22; 95% confidence interval, 0.12–0.38; P <0.001). In subgroup analysis, the treatment effect of prolonged DAPT was consistent across subgroups regardless of lesion location, stenting technique, or type of used drug-eluting stent.

Conclusions:

The risk of all-cause death or MI was significantly lower in the ≥12-month DAPT group than the <12-month DAPT group after percutaneous coronary intervention for bifurcation lesion using drug-eluting stent. Our results suggest that prolonged DAPT may improve long-term clinical outcomes after percutaneous coronary intervention for bifurcation lesions.

Clinical Trial Registration:

URL: https://www.clinicaltrials.gov . Unique identifier: NCT01642992

Intravascular ultrasound-guided vs angiography-guided drug-eluting stent implantation in complex coronary lesions: Meta-analysis of randomized trials

The relative outcomes of intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) compared with angiography-guided PCI with drug-eluting stent (DES) in complex lesions have not been established. We sought to compare the efficacy and safety of IVUS-guided PCI with angiography-guided PCI in patients with complex coronary lesions treated with DES.

METHODS

Electronic databases were searched to identify all randomized trials comparing IVUS-guided vs angiography-guided DES implantation. We evaluated major adverse cardiac events (MACE), all-cause and cardiovascular death, myocardial infarction, target lesion revascularization (TLR), target vessel revascularization (TVR), and stent thrombosis outcomes at the longest reported follow-up. Random-effects modeling was used to calculate pooled relative risk (RR) and 95% CIs.

RESULTS

Eight trials comprising 3,276 patients (1,635 IVUS-guided and 1,641 angiography-guided) enrolling only patients with complex lesions were included. Mean follow-up was 1.4±0.5years. Compared with angiography-guided PCI, patients undergoing IVUS-guided PCI had significantly lower MACE (RR 0.64, 95% CI 0.51-0.80, P=.0001), TLR (RR 0.62, 95% CI 0.45-0.86, P=.004), and TVR (RR 0.60, 95% CI 0.42-0.87, P=.007). There were no significant differences for stent thrombosis, cardiovascular death, or all-cause death. In meta-regression analysis, IVUS-guided PCI was of greatest benefit in reducing MACE in patients with acute coronary syndromes, diabetes, and long lesions.

CONCLUSIONS

The present meta-analysis demonstrates a significant reduction in MACE, TVR, and TLR with IVUS-guided DES implantation in complex coronary lesions.

Impact of Patient and Lesion Complexity on Long-Term Outcomes Following Coronary Revascularization With New-Generation Drug-Eluting Stents

Long-term clinical outcomes of new-generation drug-eluting stents in complex anatomic and clinical settings are not well defined. This study assessed the impact of patient and lesion complexity on 2-year outcomes after coronary revascularization with ultrathin strut biodegradable-polymer (BP) sirolimus-eluting stents (SES) versus durable-polymer (DP) everolimus-eluting stents (EES). In a prespecified analysis of the BIOSCIENCE randomized trial (NCT01443104), complex patients (911 of 2,119; 43%) were defined by the presence of acute ST-elevation myocardial infarction (MI); left ventricular ejection fraction ≤30%; renal dysfunction; insulin-treated diabetes; treatment of ostial lesion, bypass graft, unprotected left main lesion; or 3-vessel intervention. The primary end point was target lesion failure (TLF), a composite of cardiac death, target vessel MI, and clinically indicated target lesion revascularization. At 2 years, complex compared with simple patients had a greater risk of TLF (14.5% vs 7.4%, risk ratio 2.05, 95% confidence interval 1.56 to 2.69; p <0.001). The difference was sustained beyond 1 year on landmark analysis. Complex patients had higher rates of the patient-oriented composite end point of death, any MI, or any revascularization (23% vs 14.4%; p <0.001) as well as definite stent thrombosis (1.6% vs 0.4%, p = 0.006). There were no differences in TLF and patient-oriented composite end point between the BP-SES versus DP-EES, consistently among simple and complex patients. In conclusion, patient and lesion complexity had a durable adverse impact on clinical outcomes throughout 2 years of follow-up in this all-comers randomized trial. Safety and efficacy of new-generation BP-SES and DP-EES were comparable, irrespective of complexity status.

One-Year Outcomes After Primary Percutaneous Coronary Intervention for ST-Segment Elevation Myocardial Infarction With Varying Quantities of Coronary Artery Calcium (from a 13-Year Registry)

Coronary artery calcium (CAC) is associated with poor angiographic results and higher rates of complications after percutaneous coronary intervention (PCI). Limited data are available regarding the impact of angiographically evident CAC on long-term outcomes after primary PCI in patients presenting with ST-segment elevation myocardial infarction (STEMI). In this single-center, registry-based retrospective cohort analysis, we analyzed 2,143 consecutive patients presenting with STEMI who underwent primary PCI within 12 hours of symptom onset. Patients were divided based on degree of CAC (determined by visual inspection of angiograms) as follows: (1) moderate-to-severe CAC (n = 306; 14.3%) and (2) minimal-to-none CAC (n = 1,837; 85.7%). The primary end point was all-cause mortality at 1-year after PCI. Patients with moderate-to-severe CAC were older, women, and had higher rates of hypertension, chronic kidney disease, and peripheral vascular disease. Moderate-to-severe CAC was associated with higher rates of anterior myocardial infarction, advanced Killip class, and poor final angiographic results. At 1-year follow-up, rates of all-cause mortality were higher in the moderate-to-severe CAC cohort than those in the minimal-to-none CAC cohort (8.5% vs 4.7%; p = 0.008). However, after accounting for major clinical and angiographic characteristics, moderate-to-severe CAC on presenting STEMI angiogram was no longer predictive of 1-year all-cause mortality. In conclusion, advanced CAC burden occurs in ∼15% of patients undergoing primary PCI for STEMI and reflects a marker of adverse prognosis late into follow-up after PCI.

Drug-Eluting Balloons in the Treatment of Coronary De Novo Lesions: A Comprehensive Review

Drug-eluting balloons (DEBs) have emerged as a new application in percutaneous coronary intervention. DEBs have proven successful in the treatment of in-stent restenosis, but their role in de novo lesions is less clear. This paper provides a review of the current studies where DEBs have been used in coronary de novo lesions, either as part of a DEB-only strategy or in combination with another device, mainly a bare metal stent (BMS). By searching Pubmed and Embase we were able to identify 52 relevant studies, differing in design, intervention, and clinical setting, including patients with small vessel disease, bifurcation lesions, complex long lesions, acute myocardial infarction, diabetes mellitus, and elderly. In 23 studies, a DEB was combined with a BMS, 25 studies used a DEB-only strategy with only provisional BMS implantation, and four studies combined a DEB with a drug-eluting stent (DES). In the vast majority of studies, DEB in combination with BMS does not seem to improve clinical or angiographic outcome compared with DES, whereas a DEB-only strategy seems promising, especially when predilatation and geographical mismatch are taken into account. A lower risk of recurrent thrombosis with DEB compared with DES is not evident from the current studies. In conclusion, the main indication for DEB seems to be small vessel disease, especially in clinical scenarios in which a contraindication to dual antiplatelet therapy exists. The main approach should be a DEB-only strategy with only provisional bailout stenting, which has shown interesting results in different clinical scenarios. In general, larger randomized controlled studies with prolonged follow-up comparing DEB with best in class DES are warranted. Technical developments of DEBs including the use of different drugs might potentially improve the efficacy of such treatment.

Angiographic Lesion Complexity Score and In-Hospital Outcomes after Percutaneous Coronary Intervention

OBJECTIVE

We devised a percutaneous coronary intervention (PCI) scoring system based on angiographic lesion complexity and assessed its association with in-hospital complications.

BACKGROUND

Although PCI is finding increasing application in patients with coronary artery disease, lesion complexity can lead to in-hospital complications.

METHODS

Data from 3692 PCI patients were scored based on lesion complexity, defined by bifurcation, chronic total occlusion, type C, and left main lesion, along with acute thrombus in the presence of ST-segment elevation myocardial infarction (1 point assigned for each variable).

RESULTS

The patients' mean age was 67.5 +/- 10.8 years; 79.8% were male. About half of the patients (50.3%) presented with an acute coronary syndrome, and 2218 (60.1%) underwent PCI for at least one complex lesion. The patients in the higher-risk score groups were older (p < 0.001) and had present or previous heart failure (p = 0.02 and p = 0.01, respectively). Higher-risk score groups had significantly higher in-hospital event rates for death, heart failure, and cardiogenic shock (from 0 to 4 risk score; 1.7%, 4.5%, 6.3%, 7.1%, 40%, p < 0.001); bleeding with a hemoglobin decrease of >3.0 g/dL (3.1%, 11.0%, 13.1%, 10.3%, 28.6%, p < 0.001); and postoperative myocardial infarction (1.5%, 3.1%, 3.8%, 3.8%, 10%, p = 0.004), respectively. The association with adverse outcomes persisted after adjustment for known clinical predictors (odds ratio 1.72, p < 0.001).

CONCLUSION

The complexity score was cumulatively associated with in-hospital mortality and complication rate and could be used for event prediction in PCI patients.

The SYNTAX Score Can Predict Major Adverse Cardiac Events Following Percutaneous Coronary Intervention

OBJECTIVES

The SYNTAX score is a grading system that evaluates the complexity and prognosis of patients undergoing percutaneous coronary intervention (PCI). We investigated the association between the incidence of major adverse cardiac events (MACE) following PCI and the SYNTAX score in patients with three-vessel disease.

METHODS

We consecutively enrolled 381 patients with three-vessel disease undergoing PCI and stenting. The SYNTAX score was divided into tertiles as low (≤16), intermediate (16-22) and high (>22). The endpoint was the incidence of MACE defined as cardiac death, in-hospital mortality, nonfatal myocardial infarction (MI), or target vessel revascularization. Then, the incidence of MACE was compared among the SYNTAX score tertile groups.

RESULTS

The median follow-up was 14 months, and the rate of MACE was 12.6%. The rates of MACE were 7.5%, 9.9%, and 21.6% in patients with low, intermediate, and high SYNTAX score tertiles, respectively. Higher SYNTAX scores significantly predicted a higher risk of MACE (hazard ratio = 2.36; P = 0.02) even after adjustment for potential confounders. The main predictors of MACE were SYNTAX score, advanced age, hyperlipidemia, presentation as recent ST-elevation MI, number of total lesions, and history of renal failure.

CONCLUSION

The SYNTAX score could predict major cardiac outcomes following PCI in patients with three-vessel disease.

Relation between coronary calcium and major bleeding after percutaneous coronary intervention in acute coronary syndromes (from the Acute Catheterization and Urgent Intervention Triage Strategy and Harmonizing Outcomes With Revascularization and Stents in Acute Myocardial Infarction Trials)

Percutaneous coronary intervention (PCI) of calcified coronary lesions has been associated with increased rates of adverse ischemic events. However, the potential association between the presence and severity of calcific deposits and bleeding complications has yet to be investigated. Data from 6,855 patients with non-ST-segment elevation acute coronary syndrome (NSTEACS) or ST-segment elevation myocardial infarction (STEMI) treated with PCI were pooled from 2 large-scale randomized controlled trials-Acute Catheterization and Urgent Intervention Triage Strategy and Harmonizing Outcomes with Revascularization and Stents in Acute Myocardial Infarction. Patients were stratified into 3 groups according the grade of target PCI lesion calcium (none to mild, moderate, and severe) as assessed by an independent angiographic core laboratory. Thirty-day bleeding event rates were assessed and compared among groups. In the total cohort undergoing PCI, none-to-mild target lesion calcium was found in 4,665 patients (68.1%), moderate target lesion calcium in 1,788 patients (26.1%), and severe target lesion calcium in 402 patients (5.9%). The 30-day rates of non-coronary artery bypass graft surgery major bleeding increased significantly with each degree of coronary calcium (none to mild = 5.9%, moderate = 7.2%, and severe = 11.2%, p = 0.0003). By multivariable analysis, presence of severe calcium was an independent predictor of non-coronary artery bypass graft major bleeding after PCI (hazard ratio 1.54, 95% confidence interval 1.09 to 2.17, p = 0.01). In conclusion, in patients undergoing PCI for non-ST-segment elevation acute coronary syndrome and ST-segment elevation myocardial infarction, target lesion coronary calcium was an independent predictor of major bleeding events. Further studies are needed to elucidate mechanisms underlying this finding and to optimize treatment of this high-risk population.

Overview of Technical and Cost Considerations in Complex Percutaneous Coronary Intervention

Complex percutaneous coronary intervention (PCI), encompassing an ever-expanding range of challenging lesion sets and patient populations, accounts for a significant proportion of PCI procedures being performed currently. Specific lesion types associated with lower rates of procedural success and higher rates of recurrence or major adverse cardiac events (MACE) include multivessel disease, unprotected left main coronary artery disease, fibrocalcific or undilatable lesions, chronic total occlusions, degenerated saphenous vein graft lesions, thrombotic lesions, and bifurcation disease. Validated tools and technical strategies currently exist to address most procedural scenarios encountered and should be familiar to the complex PCI operator. Anticipated clinical outcomes, projected resource utilization, and cost considerations should all factor into the decisions of when, how, and in whom to intervene.

Recent perspective on coronary artery bifurcation interventions

Coronary bifurcation lesions are frequent in routine practice, accounting for 15-20% of all lesions undergoing percutaneous coronary intervention (PCI). PCI of this subset of lesions is technically challenging and historically has been associated with lower procedural success rates and worse clinical outcomes compared with non-bifurcation lesions. The introduction of drug-eluting stents has dramatically improved the outcomes. The provisional technique of implanting one stent in the main branch remains the default approach in most bifurcation lesions. Selection of the most effective technique for an individual bifurcation is important. The use of two-stent techniques as an intention to treat is an acceptable approach in some bifurcation lesions. However, a large amount of metal is generally left unapposed in the lumen with complex two-stent techniques, which is particularly concerning for the risk of stent thrombosis. New technology and dedicated bifurcation stents may overcome some of the limitations of two-stent techniques and revolutionise the management of bifurcation PCI in the future.

Clinical outcome of patients with de novo coronary bifurcation lesions treated with the Tryton Side Branch Stent. The SAFE-TRY prospective multicenter single arm study

BACKGROUND

Coronary bifurcation lesions represent a difficult problem regularly confronting interventional cardiologist, in part due to the lack of dedicated device.

OBJECTIVE

To investigate the feasibility, safety and effectiveness of the Tryton Side Branch Stent (Tryton Medical, Durham, NC, USA), a dedicated bare metal stent deployed in conjunction with a standard drug-eluting stent to treat bifurcation lesions.

METHODS

The SAFE-TRY is a prospective single arm multicenter registry including patients with de novo bifurcation lesions in native coronary arteries and syntax score <32. The primary endpoint was target vessel failure (TVF) at 30 days that comprised cardiac death, target vessel myocardial infarction and clinically driven target vessel revascularization. Secondary endpoints included device, angiographic and procedural success, 9-month major adverse cardiac and cerebrovascular event (MACCE), and stent thrombosis (ST) rates (ClinicalTrials.gov identifier: NCT01174433).

RESULTS

Among 252 enrolled patients, 24% had diabetes and 35.3% unstable angina. True bifurcation lesions involving both branches occurred in 96.8% of cases with Medina classification 1.1.1 in 62%. The left anterior descending artery and the left main were treated in 70% and 8.3% of the patients, respectively. A 6 Fr guide catheter was used in 61% of the cases. Device, angiographic and procedural success rates were 99.6%, 99.6% and 97.2% respectively. The 30-day TVF was 2.8%; the 9-month MACCE rate was 13.7%, with target lesion revascularization being 4.4%. No definite ST occurred.

CONCLUSIONS

This prospective, multicenter study confirmed the feasibility, safety and effectiveness of the Tryton Side Branch Stent to treat patients with de novo complex bifurcation lesions.

'Mother-in-child' thrombectomy technique: a novel and effective approach to decrease intracoronary thrombus burden in acute myocardial infarction

BACKGROUND

The presence of large thrombus burden in patients presenting with acute myocardial infarction (AMI) is common and associated with poor prognosis. This study aimed to describe the feasibility and safety of the novel 'mother-in-child' thrombectomy (MCT) technique in patients presenting with AMI and large thrombus burden undergoing percutaneous coronary intervention (PCI).

METHODS

We studied 13 patients presenting with AMI who underwent PCI with persistent large intracoronary thrombus after standard thrombectomy. The procedure was performed using a 5F 'Heartrail II-ST01' catheter (Terumo Medical) into a 6F guiding system. Angiographic assessment of thrombus burden and coronary flow was obtained at baseline, immediately after thrombectomy and at the end of the procedure.

RESULTS

The mean age was 55.9±13.0 years and involved mostly males (76.9%). All patients underwent PCI via radial approach. Following MCT Thrombolysis In Myocardial Infarction (TIMI) flow improved by 2 or more degrees in 11 patients (84.5%), while visible angiographic thrombus was reduced in 11 patients (84.5%). In the final angiogram, normal TIMI flow was restored in 11 patients (84.5%), with normal myocardial 'blush' in 7 patients (53.8%) and total clearance of a visible thrombus in 7 patients (53.8%). Overall, 6 patients received thrombectomy as 'stand-alone' procedure. All patients were discharged alive after a mean of 5.6±2 days.

CONCLUSION

This initial report suggests that significant reduction in thrombus burden and improvement of the coronary flow can be safely achieved in patients presenting with AMI and large thrombus burden by using the novel MCT technique.

Stenting of complex lesions: an overview

Contemporary management of coronary artery disease relies increasingly on percutaneous techniques combined with medical therapy. Although percutaneous coronary intervention (PCI) can be performed successfully in most lesions, several difficult lesion subsets continue to present unique technical challenges. These complex lesions may be classified according to anatomic criteria, including extensive calcification, thrombus, and chronic occlusions, or by location, such as bifurcations, saphenous vein grafts and unprotected left main. PCI of these lesions often requires novel devices, such as drug-eluting stents, hydrophilic guidewires, distal protection balloons or filters, thrombectomy catheters, rotational atherectomy, and cutting balloons. An integrated approach that combines these devices with specialized techniques and adjunctive pharmacologic agents has greatly improved PCI success rates for these complex lesions.

Predictive accuracy of SYNTAX score for predicting long-term outcomes of unprotected left main coronary artery revascularization

The American College of Cardiology/American Heart Association recently updated recommendations for percutaneous coronary intervention (PCI) of unprotected left main coronary artery (ULMCA) disease from class III to II(b) according to the results of the SYNergy between percutaneous coronary intervention with TAXus and cardiac surgery (SYNTAX) trial. The SYNTAX score is an angiographic tool using solely the coronary anatomy. We studied the effect of co-morbidities (Parsonnet's score) on the ability of the SYNTAX score to predict long-term outcomes in patients with ULMCA disease treated by revascularization. A total of 328 patients underwent revascularization of ULMCA from April 2003 to February 2007. Of the 328 patients, 120 underwent PCI (median follow-up 973 days) and 208 underwent coronary artery bypass grafting (CABG) (median follow-up 1,298 days). The ability of the SYNTAX score to predict outcomes was assessed using the Cox proportional hazards model. The outcomes between the PCI and CABG groups were compared by propensity analysis. The median SYNTAX score was 26 in the PCI and 28 in the CABG group (p = 0.5). In the PCI group, greater quartiles were associated with worse survival (62.1% at SYNTAX score of ≥36 vs 82.4% at SYNTAX score of <36, p = 0.03) and all-cause mortality, myocardial infarction, cerebrovascular events, and target vessel revascularization-free (MACCE) survival (47.7%, SYNTAX score ≥20 vs 76.6%, SYNTAX score <20, p = 0.02). Using the Parsonnet score as a covariate, the SYNTAX score continued to be an independent predictor of MACCE and demonstrated a trend toward predicting mortality in the PCI group. In contrast, the SYNTAX score did not predict the outcomes for the CABG group. No difference was found in mortality between the PCI and CABG groups for ULMCA disease, regardless of coronary complexity; although greater SYNTAX scores were associated with increased MACCE rates with PCI compared to CABG. Both the coronary anatomy (SYNTAX score) and co-morbidities (Parsonnet's score) predicted long-term outcomes for PCI of ULMCA disease. In contrast, the SYNTAX score did not predict the outcomes after CABG. In conclusion, the ideal scoring system to guide an appropriate revascularization decision for ULMCA disease should take into account both the coronary anatomy and the co-morbidities.

Temporal trends in patient-reported angina at 1 year after percutaneous coronary revascularization in the stent era: a report from the National Heart, Lung, and Blood Institute-sponsored 1997-2006 dynamic registry

BACKGROUND

Percutaneous coronary intervention (PCI) has witnessed rapid technological advancements, resulting in improved safety and effectiveness over time. Little, however, is known about the temporal impact on patient-reported symptoms and quality of life after PCI.

METHODS AND RESULTS

Temporal trends in post-PCI symptoms were analyzed using 8879 consecutive patients enrolled in the National Heart, Lung, and Blood Institute-sponsored Dynamic Registry (wave 1: 1997 [bare metal stents], wave 2: 1999 [uniform use of stents], wave 3: 2001 [brachytherapy], wave 4, 5: 2004, 2006 [drug eluting stents]). Patients undergoing PCI in the recent waves were older and more often reported comorbidities. However, fewer patients across the waves reported post-PCI angina at one year (wave 1 to 5: 24%, 23%, 18%, 20%, 20%; P(trend)<0.001). The lower risk of angina in recent waves was explained by patient characteristics including use of antianginal medications at discharge (relative risk [95% CI] for waves 2, 3, 4 versus 1: 1.0 [0.9 to 1.2], 0.9 [0.7 to 1.1], 1.0 [0.8 to 1.3], 0.9 [0.7 to 1.1]). Similar trend was seen in the average quality of life scores over time (adjusted mean score for waves 1 to 5: 6.2, 6.5, 6.6 and 6.6; P(trend)=0.01). Other factors associated with angina at 1 year included younger age, female gender, prior revascularization, need for repeat PCI, and hospitalization for myocardial infarction over 1 year.

CONCLUSIONS

Favorable temporal trends are seen in patient-reported symptoms after PCI in routine clinical practice. Specific subgroups, however, remain at risk for symptoms at 1 year and thus warrant closer attention.

Twenty-year evolution of percutaneous coronary intervention and its impact on clinical outcomes: a report from the National Heart, Lung, and Blood Institute-sponsored, multicenter 1985-1986 PTCA and 1997-2006 Dynamic Registries

BACKGROUND

Percutaneous coronary intervention (PCI) has undergone rapid progress, both in technology and adjunct therapy. However, documentation of long-term temporal trends in relation to contemporary practice is lacking.

METHODS AND RESULTS

We analyzed PCI use and outcomes in 8976 consecutive patients in the multicenter, National Heart, Lung, and Blood Institute-sponsored 1985-1986 percutaneous transluminal coronary angioplasty (PTCA) and 1997-2006 Dynamic Registries waves (wave 1: 1997-1998, bare-metal stents; wave 2: 1999, uniform use of stents; wave 3: 2001-2002, brachytherapy; waves 4 and 5: 2004-2006, drug-eluting stents). Patients undergoing PCI in the recent waves were older and more often reported comorbidities than those in the balloon era. PCI was more often performed for acute coronary syndromes and, in spite of the greater disease burden, was more often selective. Procedural success was achieved and maintained more often in the stent era. Significant reductions were observed in in-hospital rates (%) of myocardial infarction (PTCA Registry: 4.9; wave 1, 2.7; wave 2, 2.8; wave 3, 1.9; wave 4, 2.6; wave 5, 2; P(trend)<0.001) and emergency coronary artery bypass surgery (PTCA Registry: 3.7; wave 1, 0.4; wave 2, 0.4; wave 3, 0.3; wave 4, 0.4; wave 5, 0; P(trend)<0.001). Compared with the PTCA Registry, risk for repeat revascularization (31 to 365 days after index PCI) was significantly lower in the dynamic waves (adjusted hazard ratio: wave 1, 0.72; wave 2, 0.51; wave 3, 0.51; wave 4, 0.30; wave 5, 0.36; P<0.05 for all).

CONCLUSIONS

Percutaneous interventions, in the last 2 decades, have evolved to include more urgent, comorbid cases, despite achieving high success rates with significantly reduced need for repeat revascularization.

Percutaneous coronary intervention in tortuous coronary arteries: associated complications and strategies to improve success

Percutaneous intervention of tortuous coronary arteries can be challenging. We describe four cases that illustrate complications associated with coronary tortuosity (coronary dissection and stent loss) and strategies that can improve procedural success (such as use of soft delivery catheters, deep guide intubation, meticulous vessel preparation, and use of short, thin-strut stents).

Heavily calcified coronary lesions preclude strut apposition despite high pressure balloon dilatation and rotational atherectomy: in-vivo demonstration with optical coherence tomography

Heavily calcified lesions (HCL) continue to present challenges that are not always solved by modern low-profile, non-compliant high-pressure balloons, or bladed balloons. Uncrossable or unexpandable lesions need lesion modification, using ablating devices such as rotational atherectomy. Three cases of HCL treated with drug-eluting stents, using a new intravascular imaging device, Optical Coherence Tomography with 10-fold superior resolution and fewer artifacts compared with conventional intravascular ultrasound, are presented. Insights from using this highly sensitive imaging technique outline the high prevalence of persistent stent strut malapposition in this group, despite the use of high-pressure dilatation or rotational atherectomy.

New bifurcation guidewire technique: a reversed guidewire technique for extremely angulated bifurcation--a case report

We experienced a successfully treated case who had 99% stenosis with a severe delay of the ostial LAD which bifurcated steeply from the LMT. On treating this extreme situation, we used the newly developed "reversed guidewire" technique, and two Cypher stents were deployed as a cullotte-stent for the LMT bifurcation successfully. The "reversed guidewire" technique is considered to be a useful method for treating of extremely angled bifurcation.

Gender-based outcomes in percutaneous coronary intervention with drug-eluting stents (from the National Heart, Lung, and Blood Institute Dynamic Registry)

Gender-based outcomes have not been evaluated in unselected patients undergoing percutaneous coronary intervention (PCI) with drug-eluting stents (DESs). We investigated whether gender influences the relative safety and efficacy of DESs compared with bare metal stents (BMSs) in routine clinical practice. Using the National Heart, Lung, and Blood Institute Dynamic Registry, in-hospital and 1-year outcomes were stratified by gender in patients who received > or =1 DES (486 women, 974 men) or BMS (631 women, 1,132 men). There were significant baseline differences by gender, including older age and a higher prevalence of co-morbidities in women and more previous coronary artery disease in men. There were no gender-related differences in in-hospital myocardial infarction, coronary artery bypass grafting, and death in those treated with BMSs or DESs. Antiplatelet use and stent thrombosis (1.3% of women vs 1.2% of men, p = 0.85) were similar at 1 year with DESs. At 1 year, patients with DESs had a lower rate of repeat PCI (14.1% in women vs 9.5%, p = 0.02; 12.0% in men vs 8.8%, p = 0.02). Adjusted 1-year outcomes in patients with BMSs and DESs, including death and myocardial infarction, were independent of gender. Use of DESs was the only factor, other than age, that conferred a lower risk for the need for repeat PCI in women (relative risk 0.61, 95% confidence interval 0.41 to 0.89, p = 0.01) and men (relative risk 0.68, 95% confidence interval 0.51 to 0.91, p = 0.001). In conclusion, the widespread use of DESs is safe and has decreased clinically driven revascularization compared with BMSs equally in women and men.

Novel stent and delivery systems for the treatment of bifurcation lesions: porcine coronary artery model

BACKGROUND

In percutaneous treatment of bifurcation coronary lesions, side-branch restenosis remains a significant limitation in current therapeutic approaches. Coronary stents with a side aperture and a sleeve may be clinically advantageous to maintain access to side branch, stabilize the side-branch orifice, and deliver the appropriate drug to the side-branch ostium.

METHODS

A novel stent system (PETAL stent; Advanced Stent Technologies, Pleasanton, CA), incorporating a side aperture with deployable struts, was compared within porcine coronary model to the prior stent version having only the side aperture (SLK-View stent). In six pigs, each stent was implanted either in the left anterior descending coronary artery or the left circumflex coronary artery with adjunctive kissing balloon dilatation. At 28-day follow-up, coronary angiography was performed.

RESULT

A total of six SLK-View stents and six PETAL stents were implanted in coronary arteries without any complication, and adjunctive kissing balloon dilatations were successful in all lesions. Quantitative coronary angiography (QCA) data at 28 days showed that PETAL stents exhibited superior QCA in mean diameter compared with SLK-View stents for side branch, inferring efficacy of PETAL ostial struts.

CONCLUSION

AST-PETAL stent has the potential to be a new solution for treatment of bifurcation lesions. Antirestenosis drug elution should be considered with this successful platform.