Drug-eluting stents in bifurcation lesions: to stent one branch or both?

Long-Term Clinical Outcomes of Drug-Coated Balloon Following Directional Coronary Atherectomy for Bifurcated or Ostial Lesions in the DCA/DCB Registry

BACKGROUND

The long-term efficacy of drug-coated balloon (DCB) angioplasty for large bifurcation lesions, particularly those involving the left main trunk (LMT), remains unclear.

AIMS

This study aimed to evaluate the long-term outcomes of directional coronary atherectomy followed by DCB (DCA/DCB) for large bifurcation lesions.

METHODS

This retrospective multicenter study analyzed 129 cases from the DCA/DCB registry, with 80.4% involving LMT bifurcation lesions. Building on previously reported 12-month outcomes, this study assessed long-term results. The primary endpoint was clinically driven (CD) target lesion revascularization (TLR) at 36 months. Secondary endpoints included CD target vessel revascularization (TVR); CD target vessel failure (TVF); and adverse events, such as all-cause mortality, cardiac death, target vessel acute myocardial infarction (AMI), and the need for coronary artery bypass grafting (CABG), at 24 and 36 months.

RESULTS

The mean follow-up was 53.4 ± 23.9 months. The CD-TLR rate was 5.0% at 24 months, and the primary endpoint was 5.9% at 36 months. CD-TVR rates were 14.0% at 24 months and 15.0% at 36 months, while CD-TVF rates were 14.9% at 24 months and 16.7% at 36 months. Adverse events included all-cause mortality rates of 0.8% at 24 months and 1.8% at 36 months, and cardiac death rates of 0.8% at both 24 and 36 months. No target vessel AMI or CABG procedures were reported.

CONCLUSION

The consistently low CD-TLR rate at 36 months supports the efficacy of the DCA/DCB strategy for large bifurcation lesions, including LMT, indicating its sustained effectiveness. These findings highlight the viability of this treatment approach.

Efficacy of drug-coated balloon angioplasty after directional coronary atherectomy for coronary bifurcation lesions (DCA/DCB registry)

OBJECTIVES

To evaluate the efficacy and safety of additional drug-coated balloon (DCB) angioplasty after directional coronary atherectomy (DCA) for coronary bifurcation lesions.

BACKGROUND

The optimal therapy for bifurcation lesions has not been established, even in the drug-eluting stent era. DCA possibly prevents plaque and carina shift in bifurcation lesions by plaque debulking; however, the efficacy of combined DCA and DCB (DCA/DCB) for bifurcation lesions remains unclear.

METHODS

This multicenter registry retrospectively recruited patients with bifurcation lesions who underwent DCA/DCB and follow-up angiogram at 6-15 months. The primary endpoint was the 12-month target vessel failure (TVF) rate. The secondary endpoints were procedure-related major complications, major cardiovascular events at 12 months, restenosis at 12 months, target lesion revascularization (TLR) at 12 months, and target vessel revascularization (TVR) at 12 months.

RESULTS

We enrolled 129 patients from 16 Japanese centers. One hundred and four lesions (80.6%) were located around the left main trunk bifurcations. No side branch compromise was found intraoperatively. Restenosis was observed in three patients (2.3%) at 12 months. TLR occurred in four patients (3.1%): 3 (2.3%) in the main vessel and 1 (0.8%) in the ostium of the side branch at 12 months. TVF incidence at 12 months was slightly higher in 14 patients (10.9%), and only two patients (1.6%) had symptomatic TVR. One patient (0.8%) had non-target vessel-related myocardial infarction.

CONCLUSIONS

Our data suggested that DCA/DCB provided good clinical outcomes and minimal side branch damage and could be an optimal non-stent percutaneous coronary intervention strategy for bifurcation lesions.

Computational Simulations of Provisional Stenting of a Diseased Coronary Artery Bifurcation Model

Although stenting of non-branched arterial segments has acceptable clinical outcomes, in-stent restenosis (ISR) and stent thrombosis remain clinically significant issues for vascular bifurcations (15-28% restenosis). Local fluid and solid stresses appear to play an important role in restenosis and thrombosis. The combined role of wall shear stress (WSS) and circumferential wall stresses (CWS) is unclear in the case of stenting at vascular bifurcations. Using numerical simulations, we computed the fluid shear, solid stresses and the stress ratio at the the bifurcation region. Stenting of main vessel increased the maximum CWS in the the side branch (SB), resulting in a nearly two-fold increase of stress ratio in the SB compared to the MB (5.1 × 10⁵ vs. 9.2 × 10⁵). The existence of plaque decreased WSS and increased CWS near the carina, increasing the stress ratio at the SB. The changes of stress ratio were highly consistent with clinical data on bifurcation stenting. Fluid dynamics and solids mechanics should be considered in planning of stenting for a specific bifurcation, as their combined biomechanical effect may play an important role in stent restenosis and thrombosis.

Biomechanical impact of provisional stenting and balloon dilatation on coronary bifurcation: clinical implications

In-stent restenosis (ISR) and stent thrombosis remain clinically significant problems for bifurcations. Although the role of wall shear stress (WSS) has been well investigated, the role of circumferential wall stresses (CWS) has not been well studied in provisional stenting with and without final kissing balloon (FKB). We hypothesized that the perturbation of CWS at the SB in provisional stenting and balloon dilatation is an important factor in addition to WSS, and, hence, may affect restenosis rates (i.e., higher CWS correlates with higher restenosis). To test this hypothesis, we developed computational models of stent, FKB at bifurcation, and finite element simulations that considered both fluid and solid mechanics of the vessel wall. We computed the stress ratio (CWS/WSS) to show potential correlation with restenosis in clinical studies (i.e., higher stress ratio correlates with higher restenosis). Our simulation results show that stenting in the main branch (MB) increases the maximum CWS in the side branch (SB) and, hence, yields a higher stress ratio in the SB, as compared with the MB. FKB dilatation decreases the CWS and increases WSS, which collectively lowers the stress ratio in the SB. The changes of stress ratio were correlated positively with clinical data in provisional stenting and FKB. Both fluid and solid mechanics need to be evaluated when considering various stenting techniques at bifurcations, as solid stresses also play an important role in clinical outcome. An integrative index of bifurcation mechanics is the stress ratio that considers both CWS and WSS.NEW & NOTEWORTHY Although the role of wall shear stress (WSS) has been well investigated, the role of circumferential wall stresses (CWS) has not been well studied in provisional stenting with and without final kissing balloon. Both fluid and solid mechanics need to be evaluated when considering various stenting techniques at bifurcations. An integrative index of bifurcation mechanics is the stress ratio that considers both CWS and WSS.

Impact of bifurcation dual stenting on endothelial shear stress

Despite advances in percutaneous coronary interventions and the introduction of drug eluding stents, in-stent restenosis and stent thrombosis remain a clinically significant problem for bifurcations. The aim of this study is to determine the effect of dual bifurcation stenting on hemodynamic parameters known to influence restenosis and thrombosis. We hypothesized that double stenting, especially with a longer side branch (SB) stent, likely has a negative effect on wall shear stress (WSS), WSS gradient (WSSG), and oscillatory shear index (OSI). To test this hypothesis, we developed computational models of dual stents at bifurcations and non-Newtonian blood simulations. The models were then interfaced, meshed, and solved in a validated finite-element package. Longer and shorter stents at the SB and provisional stenting were compared. It was found that stents placed in the SB at a bifurcation lowered WSS, but elevated WSSG and OSI. Dual stenting with longer SB stent had the most adverse impact on SB endothelial WSS, WSSG, and OSI, with low WSS region up to 50% more than the case with shorter SB stent. The simulations also demonstrated flow disturbances resulting from SB stent struts protruding into the main flow field near the carina, which may have implications on stent thrombosis. The simulations predict a negative hemodynamic role for SB stenting, which is exaggerated with a longer stent, consistent with clinical trial findings that dual-stenting is comparable or inferior to provisional stenting.

Long-term clinical outcomes of the one-stent technique versus the two-stent technique for non-left main true coronary bifurcation disease in the era of drug-eluting stents

BACKGROUND

Few studies have compared the long-term major adverse cardiac events (MACEs) between the one-stent technique (stenting only the main branch) and the two-stent technique (stenting of both the main and side branches) for the treatment of true coronary bifurcation lesions in the drug-eluting stent era. Therefore, we investigated this issue using the large nationwide coronary bifurcation registry.

METHODS

The 1,147 patients with non-left main coronary true bifurcation lesions underwent percutaneous coronary intervention in the Korea Coronary Bifurcation Stent (COBIS) registry. All patients were stratified based on the stent placement technique: one stent (n = 898) versus two stents (n = 249). MACE, including death, nonfatal myocardial infarction (MI), and repeat vessel and lesion revascularization (TVR and TLR), were evaluated.

RESULTS

The median follow-up duration was 20 months. The MACEs did not differ between the 2 groups. Findings from the one-stent group were similar to those of the two-stent group in composite of death, MI, or TVR, based on analysis by crude, multivariate Cox hazard regression model, inverse-probability-of-treatment weighting (hazard ratio [HR] 0.911, 95% confidence interval (CI) 0.614-1.351; HR 0.685 95% CI 0.381-1.232; HR 1.235, 95% CI 0.331-4.605, respectively). In further analysis with propensity score matching, the overall findings were consistent.

CONCLUSIONS

The findings of the present study indicate that the one-stent technique was not inferior to the two-stent technique for the treatment of non-left main true coronary bifurcation lesions in terms of long-term MACEs.

Long-term outcomes following primary drug-eluting stenting of infrapopliteal bifurcations

PURPOSE

To investigate the outcomes following primary deployment of drug-eluting stents (DES) for the treatment of infrapopliteal bifurcation lesions in patients suffering from critical limb ischemia (CLI).

METHODS

This was a retrospective study of a registry enrolling all patients suffering from chronic infrapopliteal artery disease and undergoing treatment of tibial bifurcation lesions with DES using 3 techniques: balloon and stent (single stent), T-shape double-stent, and culotte double-stent. The analysis included 39 CLI patients (32 men; mean age 69 ± 10 years) who underwent primary stenting of 41 infrapopliteal bifurcations. Most patients (29, 70.7%) were classified as Rutherford category 4. The mean lesion length was 31.3 ± 13.1 mm. The primary endpoints were amputation-free survival, target lesion revascularization (TLR)-free survival, angiographic 2-vessel primary patency (2VPP), and 1-vessel primary patency (1VPP). Secondary endpoints included survival and angiographic binary restenosis. A Cox regression analysis was performed to identify independent predictors influencing outcomes

RESULTS

Technical success was achieved in all cases. The mean clinical and angiographic follow-up intervals were 47.5 ± 14.8 and 17.5 ± 12.5 months, respectively. According to the Kaplan-Meier analysis, overall survival, amputation-free survival, and TLR-free survival estimates were 79.5%, 84.3%, and 58.0%, respectively, at 5 years. At 12, 24, and 36 months, the 2VPP rates were 77.2%, 47.5%, and 33.9%, and the 1VPP rates were 84.0%, 65.5%, and 54.5%, respectively. Binary restenosis rates were 26.4%, 57.3%, and 82.2% at 12, 24, and 36 months; restenotic lesions were mainly detected at the origin of the bifurcations. The regression model did not identify any independent predictors influencing outcome.

CONCLUSION

DES application for below-the-knee bifurcation lesions was safe and resulted in satisfactory long-term angiographic and clinical outcomes comparable to those reported following infrapopliteal endovascular treatment.

Crush stenting with drug-eluting stents: relevance of coronary bifurcation lesion location on angiographic and clinical outcomes

BACKGROUND

Data on the relevance of the location of coronary bifurcation lesions treated by crush stenting with outcomes were limited.

HYPOTHESIS

We hypothesized that the location of the bifurcation lesion correlated with clinical outcome.

METHOD

A total of 212 patients with 230 true bifurcation lesions treated by crush stenting with drug-eluting stents (DES) were assessed prospectively. Surveillance quantitative angiographies were indexed at 8 months after procedure. Primary endpoint was major adverse cardiac events (MACE), defined as cardiac death, myocardial infarction, and target lesion revascularization (TLR).

RESULTS

Patients in the distal right coronary artery (RCAd) group were characterized by higher proportions of prior myocardial infarction and very tortuous lesions. However, lesions in the RCAd group, compared to those of other groups, had the lowest late lumen loss, with resultant lowest incidence of MACE at a mean follow-up of 268±35 days. Independent predictors of MACE included unsatisfied kissing (KUS; hazard ratio [HR]: 12.14, 95% confidence interval [CI]: 4.01-12.10, P = .001) and non-RCA lesion (HR: 20.69, 95% CI: 5.05-22.38, P = .001), while those of TLR were KUS (HR: 10.21, 95% CI: 0.01-0.34, P = .002), bifurcation angle (HR: 4.728, 95% CI: 2.541-4.109, P = .001), and non-RCA lesion (HR: 16.05, 95%CI: 1.01-4.83, P = .001).

CONCLUSIONS

Classical crush stenting with drug-eluting stents is associated with significantly better outcomes in RCAd. Quality of kissing inflation is mandatory to improve outcome.

Off-label use of drug-eluting versus bare metal stents: a lesion-specific systematic review of long-term outcomes

OBJECTIVE

The purpose of this systematic review was to evaluate differences in lesion-specific outcomes with the "off-label" use of drug-eluting stents (DES) versus bare metal stents (BMS).

METHODS

MEDLINE, PubMed, the Cochrane databases, and other Web were searched for studies evaluating off-label use of DES and BMS with the same characteristics. Of 1,258 abstracts or manuscripts reviewed, 112 studies were included (total N = 23,438). Studies were excluded if patients received both types of stent or no stent; lesion type was unknown; lesion-specific outcomes for ≥6 months were unavailable; or <25 patients were enrolled.

RESULTS

Overall mortality at 6-12 months was approximately 3% for BMS and DES for off-label use. Increase in mortality was greater from 6-12 months to 2 years with BMS than with DES (3.3%-9.1%; 2.8%-4.1%); however, rates were similar at 3 years (BMS: 18.8%; DES:15.3%). Myocardial Infarction rates were similar for both types at 6-12 months (BMS: 6.5%; DES: 6.0%). Overall rates of stent thrombosis were 1.8% and 1.7% for BMS and DES, respectively. Similar or slightly lower rates of stent thrombosis were seen for most lesion types, except higher rates for small vessels for BMS (5.2%) and true bifurcation for DES (3.3%). Rates of target lesion revascularization (TLR) were 7.5% for BMS and 19.6% for DES at 6-12 months. At 2-years TLR remained lower than DES. When the combined group was compared to registry data alone, similar values were seen.

CONCLUSIONS

Rates of mortality, myocardial infarction (MI), and stent thrombosis were similar in patients receiving BMS or DES, while TLR rates were lower in DES patients.

Very long-term results comparing a simple versus a complex stenting strategy in the treatment of coronary bifurcation lesions

BACKGROUND

The optimal stenting strategy for coronary bifurcation lesions has not yet been defined, especially given the lack of very long-term data (>24 months). We compared our long-term results of a simple vs complex stenting strategy in patients with bifurcation lesions.

METHODS

We retrospectively selected subjects undergoing percutaneous coronary intervention (PCI) with stenting in a bifurcation lesion between June 2002 and December 2005, comparing those treated with a simple technique vs those treated with a complex one. The primary end-point was the rate of major adverse cardiac events (MACE) at >24 months of follow-up.

RESULTS

A total of 326 patients were included, 64.7% treated with a simple technique (Group A) and 35.3% with a complex strategy (Group B). Drug-eluting stents were used in 82.0% and 73.0%, respectively (P = 0.059), final kissing balloon in 47.9% and 53.0% (P = 0.37), and procedural success obtained in 99.5% and 99.1% (P = 0.66). After a median of 34 months, MACE occurred in 52 (26.5%) in Group A and in 32 (31.4%) in Group B (P = 0.37), cardiac death in six (3.1%) vs four (3.9%, P = 0.70), myocardial infarction in 13 (6.6%) vs 6 (5.9%, P = 0.80), target vessel revascularization in 36 (18.4%) vs 29 (28.4%, P = 0.04), and bypass in five (2.6%) vs two (2%, P = 0.74). Definite stent thrombosis was adjudicated in two (1%) vs one (0.9%, P = 0.98).

CONCLUSIONS

This study, comparing simple and complex stenting strategies for the treatment of coronary bifurcation lesions, shows that both techniques are associated with favorable clinical results and low adverse events rates at long-term follow-up.

Evaluation of a strategy for treating bifurcated lesions by single or double stenting based on the Medina classification

INTRODUCTION AND OBJECTIVES

The Medina bifurcated lesion classification has been widely adopted because of its simplicity. However, no data are available on its use in helping select the best stenting technique for bifurcations.

METHODS

Consecutive patients with bifurcated lesions (side branch >or=2.25 mm) were prospectively assessed using the Medina classification. The treatment strategy studied involved implanting two stents in lesions with a Medina classification of 1,1,1 (M3 group) and one stent in only the main vessel in lesions with other Medina classifications (OM group). Clinical endpoints were a major adverse cardiac event (MACE) and target lesion revascularization (TLR) during hospitalization and at 12-month follow-up.

RESULTS

The study included 120 patients: 25 in the M3 group and 95 in the OM group. There was no difference in baseline characteristics between the groups. The treatment strategy was successfully implemented in 97% of the OM group and 68% of the M3 group (P< .001). No death or TLR was recorded during hospitalization, though three myocardial infarctions occurred postoperatively (2.1% in the OM group vs 4.0% in the M3 group; P=.6). At 12 months, there was no difference in clinical outcome between the two groups (MACE: 12.6% in the OM group vs 8% in the M3 group; P=.4; TLR: 13.7% in the OM group vs 8% in the M3 group; P=.5). Multivariate analysis showed that bare metal stent implantation (only in patients receiving a single stent) was the only independent predictor of TLR.

CONCLUSIONS

The planned treatment strategy of implanting a single stent in patients with bifurcated lesions not classified as Medina 1,1,1 lesions was associated with a very low rate of second stent implantation. Moreover, bare metal stent use was a predictor of TLR, suggesting that drug-eluting stents should be used routinely to treat bifurcated lesions regardless of their angiographic complexity.

Study comparing the double kissing (DK) crush with classical crush for the treatment of coronary bifurcation lesions: the DKCRUSH-1 Bifurcation Study with drug-eluting stents

BACKGROUND

Classical crush has a lower rate of final kissing balloon inflation (FKBI) immediately after percutaneous coronary intervention (PCI). The double kissing (DK) crush technique has the potential to increase the FKBI rate, and no prospective studies on the comparison of classical with DK crush techniques have been reported.

MATERIALS AND METHODS

Three hundred and eleven patients with true bifurcation lesions were randomly divided into classical (n = 156) and DK crush (n = 155) groups. Clinical and angiographic details at follow-up at 8 months were indexed. The primary end point was major adverse cardiac events (MACE) including myocardial infarction, cardiac death and target lesion revascularization (TLR) at 8 months.

RESULTS

FKBI was 76% in the classical crush group and 100% in the DK group (P < 0.001). The incidence of stent thrombosis was 3.2% in the classical crush group (5.1% in without- and 1.7% in with-FKBI) and 1.3% in the DK crush group. Cumulative 8 month MACE was 24.4% in the classical crush group and 11.4% in the DK crush group (P = 0.02). The TLR-free survival rate was 75.4% in the classical crush group and 89.5% in the DK crush group (P = 0.002).

CONCLUSIONS

DK crush technique has the potential of increasing FKBI rate and reducing stent thrombosis, with a further reduction of TLR and cumulative MACE rate at 8 months.

Crush Stenting With Paclitaxel-Eluting or Sirolimus-Eluting Stents for the Treatment of Coronary Bifurcation Lesions

Two hundred forty-six patients with 252 bifurcation lesions were enrolled into a prospective, nonrandomized study to use paclitaxel-eluting or sirolimus-eluting stent for crush stenting in the treatment of coronary bifurcation lesions. Compared with the sirolimus-eluting stent group, the paclitaxel-eluting stent group had significantly higher mean late lumen and binary angiographic restenosis rates. Sirolimus-eluting stent versus paclitaxel-eluting stent recipients had significantly lower in-segment restenosis in the entire main vessel (15.7% vs 3.1%, P = .004), and simultaneous side branch and main vessel restenoses were solely detected in the paclitaxel-eluting stent group (11.9% vs 0%, P = .03). Target-lesion vessel revascularization and cumulative major adverse cardiac events rates were significantly higher in the paclitaxel-eluting versus the sirolimus-eluting stent group (17.99% vs 8.41%, P = .01; 19.4 vs 9.3%, P = .01; 23.6 vs 11.2%, P = .03). In this study with crush stenting, use of sirolimus-eluting stent, compared with paclitaxel-eluting stent, yielded significantly lower late lumen loss, restenosis, and revascularization rates, with comparable safety by 8-month follow-up.