Percutaneous coronary intervention for major bifurcation lesions using the simple approach: risk of myocardial infarction

Coronary Bifurcation Stenting: Review of Current Techniques and Evidence

BACKGROUND

Coronary bifurcation stenting constitutes 20% of all PCI performed. Given the extensive prevalence of bifurcation lesions, various techniques have sought to optimally stent the bifurcation to improve revascularization while also decreasing rates of stent thrombosis and lesion recurrence. Advanced techniques, such as planned two-stent approaches, have been shown to have improved outcomes but also require fluoroscopy and procedure time, posing an economic argument as well as a patient-outcome one.

OBJECTIVE

Because of the many strategies posited in the literature, it becomes essential to objectively evaluate evidence from randomized controlled trials and meta-analyses to help determine the optimal stenting strategy.

METHODS

We reviewed the clinical evidence on the efficacy of coronary bifurcation stenting.

RESULTS

In this paper, we review the most recent randomized controlled trials and meta-analyses on the efficacy of various stenting techniques and advances in stenting technologies published to gauge the current state of understanding and chart where the field is heading.

CONCLUSION

Bifurcation stenting is a maturing problem in the field of interventional cardiology that is adapting to the needs of the patients and advances in technology.

Inflation Pressure in Side Branch during Modified Jailed Balloon Technique Does Not Affect Side Branch Outcomes

Objectives

This study aimed to investigate the optimal jailed balloon inflation in the side branch during the modified jailed balloon technique for bifurcated lesions.

Background

The modified jailed balloon technique is one of the effective techniques to minimize the emergence of side branch (SB) compromise by preventing plaque or carina shifting during a single stent strategy in the main vessel with provisional SB treatment. However, there are no detailed studies on the method of optimal jailed balloon inflation.

Methods

We analyzed 51 consecutive patients who underwent percutaneous coronary intervention (PCI) for bifurcated lesions with a modified jailed balloon technique between September 2018 and December 2020. These 51 patients were divided into two groups according to the magnitude of inflation pressure of the jailed balloon: a higher pressure (HP) group and lower pressure (LP) group.

Results

No significant differences in procedural outcomes were observed between the two groups. The findings of SB compromise were relatively common with our procedure (30.0% in the HP group; 33.3% in the LP group). The patterns of SB compromise such as dissection or stenosis increase were observed at similar frequencies between them. In particular, SB dissection was noted in the SB lesion with some plaque burden, irrespective of the magnitude of the jailed balloon inflation pressure. Univariate analysis showed that calcification in the main vessel and SB lesion length was significantly associated with SB compromise. Finally, all PCI procedures were successfully completed without any provisional stent deployment in SB.

Conclusions

We speculate that lesion characteristics rather than the PCI procedural factors may be critical determinants to cause SB compromise.

Acute Angiographic and Intermediate-Term Clinical Results of Patients with Non-Left Main Coronary Bifurcation Lesions Treated with BVS by Jailed Semi-Inflated Balloon Technique and Provisional Side-Branch Stenting Strategy

Background

To evaluate the acute angiographic and intermediate-term clinical results of patients with non-left main (LM) coronary artery bifurcation disease (CABD) treated with BVS, as compared with those treated with DES, using the jailed semi-inflated balloon technique (JSIBT) for side branch (SB) protection and provisional stenting.

Methods and Results

Sixty-eight patients with non-LM CABD who had undergone provisional one-stent implantation with SB protection by JSIBT between January 2015 and December 2017 were retrospectively enrolled. Among them, 20 patients received Absorb BVS implantation and 48 patients received DES implantation. Patients in the BVS group were younger and had higher BMI, total cholesterol, low-density lipoprotein cholesterol, and hemoglobin but had lower serum creatinine and lower prevalence of prior PCI and MI. No SB balloon rupture/entrapment occurred in either group. The incidence of SB dissection/occlusion and SB in need of rewiring or stenting was rare in both groups and showed no significant difference between them. Postinterventional TIMI flow significantly increased in both groups. The intermediate-term clinical outcomes were good in terms of incidence of target lesion failure, target lesion revascularization, target vessel revascularization, myocardial infarction, and all-cause death in both groups.

Conclusion

The use of JSIBT for treating CABD with modern BVS can provide SB protection as similar as those with DES, even with higher incidence of acute SB dissection/occlusion. The immediate angiographic results and acute and intermediate-term clinical outcomes were also similar in both groups. Our study results demonstrate that JSIBT might be a safe and alternative SB protection tool for BVS in patients with complex CABD.

Prevalence and characteristics of dual left anterior descending artery in adult patients undergoing coronary angiography

Aim: To determine the prevalence and characteristics of dual left anterior descending artery (LAD) in adults undergoing catheter coronary angiography. Materials & methods: We identified cases with dual LAD by retrospectively analyzing 3233 angiograms done from January 2017 to June 2019. Results: Dual LAD was seen in 22 patients (0.68%). We identified type I dual LAD in 14 cases, type II in 7 cases and type III in 1 case. Significant stenosis was seen in proximal part of long LAD in 12 cases, in LAD proper in 7 cases and in proximal part of short LAD in 4 cases. Conclusion: Dual LAD is a rare anomaly. Its sound knowledge is essential for proper management of patients with coronary artery disease.

Safety of hydrophilic guidewires used for side-branch protection during stenting and proximal optimization technique in coronary bifurcation lesions

BACKGROUND AND PROPOSE

In coronary bifurcation lesions (CBL), hydrophilic guidewires used for side-branch (SB) protection can be withdrawn from underneath the stent easier than other wires. However, the safety of which has not been investigated.

METHODS/MATERIALS

We performed scanning electron microscopic (SEM) examination of hydrophilic wires - the Whisper and Runthrough wires - used for SB protection during stenting and proximal optimization technique (POT) in 30 patients with CBL. The distal 15cm of the wire was examined every 1mm by SEM and 4500 segments were analyzed to investigate for wire fracture, polymer shearing (PS), and its correlations with post-stenting creatine kinase (CK)-MB release.

RESULTS

SEM examination showed no evidence for wire fracture. The total area of PS and the largest defect on the wire were significantly larger with the Whisper wire versus the Runthrough wire (0.15±0.04mm² vs. 0.026±0.01mm² and 0.04±0.05mm² vs. 0.01±0.01mm²; P<0.05, respectively). The total length of PS and the longest defect on the wire were significantly longer with the Whisper wire vs. the Runthrough wire (12.1±14.5mm vs. 2.7±3.0mm and 2.9±4.2mm vs. 1.0±1.2mm; P<0.05, respectively), but there were weak correlations between the extents of PS with CK-MB release.

CONCLUSIONS

Hydrophilic guidewires may be safely used for SB protection during stenting and POT in CBLs. The extent of PS was significantly greater with the Whisper wire than with the Runthrough wire, but its correlation with post-stenting CK-MB release was weak.

Clinical and angiographic predictors of major side branch occlusion after main vessel stenting in coronary bifurcation lesions

Background:

Major side branch (SB) occlusion is one of the most serious complications during percutaneous coronary intervention (PCI) for bifurcation lesions. We aimed to characterize the incidence and predictors of major SB occlusion during coronary bifurcation intervention.

Methods:

We selected consecutive patients undergoing PCI (using one stent or provisional two stent strategy) for bifurcation lesions with major SB. All clinical characteristics, coronary angiography findings, PCI procedural factors and quantitative coronary angiographic analysis data were collected. Multivariate logistic regression analysis was performed to identify independent predictors of SB occlusion. SB occlusion after main vessel (MV) stenting was defined as no blood flow or any thrombolysis in myocardial infarction (TIMI) flow grade decrease in SB after MV stenting.

Results:

Among all 652 bifurcation lesions, 32 (4.91%) SBs occluded. No blood flow occurred in 18 lesions and TIMI flow grade decreasing occurred in 14 lesions. In multivariate analysis, diameter ratio between MV/SB (odds ratio [OR]: 7.71, 95% confidence interval [CI]: 1.53–38.85, P = 0.01), bifurcation angle (OR: 1.03, 95% CI: 1.02–1.05, P < 0.01), diameter stenosis of SB before MV stenting (OR: 1.05, 95% CI: 1.03–1.07, P < 0.01), TIMI flow grade of SB before MV stenting (OR: 3.59, 95% CI: 1.48–8.72, P < 0.01) and left ventricular eject fraction (LVEF) (OR: 1.06, 95% CI: 1.02–1.11, P < 0.01) were independent predictors of SB occlusion.

Conclusions:

Among clinical and angiographic findings, diameter ratio between MV/SB, bifurcation angle, diameter stenosis of SB before MV stenting, TIMI flow grade of SB before MV stenting and LVEF were predictive of major SB occlusion after MV stenting.

Optimal Revascularization Strategy on Medina 0,1,0 Left Main Bifurcation Lesions in Type 2 Diabetes

Aim. Diabetes mellitus (DM) is a major risk factor for cardiovascular disease. The implications of a diagnosis of DM are as severe as the diagnosis of coronary artery disease. For many patients with complex coronary artery disease, optimal revascularization strategy selection and optimal medical therapy are equally important. In this study, we compared the hemodynamic results of different stenting techniques for Medina 0,1,0 left main bifurcation lesions. Methods. We use idealized left main bifurcation models and computational fluid dynamics analysis to evaluate hemodynamic parameters which are known to affect the risk of restenosis and thrombosis at stented bifurcation. The surface integrals of time-averaged wall shear stress (TAWSS) and oscillatory shear index (OSI) at bifurcation site were quantified. Results. Crossover stenting without final kissing balloon angioplasty provided the most favorable hemodynamic results (integrated values of TAWSS = 2.96 × 10^-4 N, OSI = 4.75 × 10^-6 m²) with bifurcation area subjected to OSI values >0.25, >0.35, and >0.45 calculated as 0.39 mm², 0.06 mm², and 0 mm², respectively. Conclusion. Crossover stenting only offers hemodynamic advantages over other stenting techniques for Medina 0,1,0 left main bifurcation lesions and large bifurcation angle is associated with unfavorable flow profiles.

A Novel-Modified Provisional Bifurcation Stenting Technique: Jailed Semi-Inflated Balloon Technique

OBJECTIVE

We proposed a new technique for the treatment of coronary bifurcation lesions, called jailed semi-inflated balloon technique (JSBT).

BACKGROUND

Currently, provisional approach is recommended to treat most of coronary bifurcation lesions. However, it is associated with the risk of side branch (SB) occlusion after main vessel (MV) stenting due to plaque or carina shift into the SB. The SB occlusion may cause peri-procedural myonecrosis or hemodynamic compromise. Therefore, strategies are needed to reduce the SB occlusion during provisional approach.

METHODS

Between September 2014 and April 2015, we selected 137 patients (104 male, 33 female; mean age 63.6 ± 11.7 years) with 148 distinct coronary bifurcation lesions underwent percutaneous coronary intervention using JSBT. All patients were followed with hospital visits or telephone contact up to 1 month.

RESULTS

The majority of the patients had acute coronary syndrome (64.2%) and Medina 1.1.1. bifurcation lesions (62.8%). The lesion localization was distal left main (LM) coronary artery in 28 patients. After the MV stenting, thrombolysis in myocardial infarction (TIMI) 3 flow was established in 100% of both MV and SB. There was no SB occlusion in any patient. There was no major adverse cardiac event during in-hospital stay and 1 month follow-up.

CONCLUSIONS

The JSBT technique can be successfully performed in both LM and non-LM bifurcation lesion. This technique provides high rate of procedural success, excellent SB protection during MV stenting and excellent immediate clinical outcome.

Predictors and Periprocedural Myocardial Injury Rate of Small Side Branches Occlusion in Coronary Bifurcation Intervention

Occlusion of small side branch (SB) may result in significant adverse clinical events. We aim to characterize the predictors of small SB occlusion and incidence of periprocedural myocardial injury (PMI) in coronary bifurcation intervention.Nine hundred twenty-five consecutive patients with 949 bifurcation lesions (SB ≤ 2.0  mm) treated with percutaneous coronary intervention (PCI) were studied. All clinical characteristics, coronary angiography findings, PCI procedural factors, and quantitative coronary angiographic analysis data were collected. SB occlusion after main vessel (MV) stenting was defined as no blood flow or any thrombolysis in myocardial infarction (TIMI) flow grade decrease in SB after MV stenting. Multivariate logistic regression analysis was performed to identify independent predictors of small SB occlusion. Creatine kinase-myocardial band activity was determined by using an immunoinhibition assay and confirmed by mass spectrometry. Incidence of PMI between no SB occlusion group and SB occlusion group was compared.SB occlusion occurred in 86 (9.1%) of 949 bifurcation lesions. Of SB occlusion, total occlusion occurred in 64 (74.4%) lesions and a decrease in TIMI flow occurred in 22 (25.6%) lesions. True bifurcation lesion, irregular plaque, predilation in SB, preprocedural SB TIMI flow grade, preprocedural diameter stenosis of distal MV, preprocedural diameter stenosis of bifurcation core, bifurcation angle, diameter ratio between MV and SB, diameter stenosis of SB before MV stenting, and MV lesion length were independent risk factors of SB occlusion. We observed a significantly higher incidence of PMI in each cutoff level in patients with SB occlusion compared with those without SB occlusion.True bifurcation lesion, irregular plaque, and 8 other predictors were independent predictors of SB occlusion. Patients with small SB occlusion had significant higher incidence of PMI.

Coronary bifurcation lesions: Present status and future perspectives

Coronary bifurcation lesions (CBLs) are challenging and associated with a higher rate of adverse events than non-bifurcation lesions. In the era of drug-eluting stents, 2 primary interventional strategies for treating CBL include the complex strategy the main vessel (MV) and side-branch (SB) stenting, and the simple strategy MV stenting combined with provisional SB stenting. The meta-analysis of the simple vs. complex strategies demonstrated an increased incidence of myocardial infarction in the complex strategy. Likewise, the Tryton dedicated bifurcation stents, as compared with the simple strategy, increased the rate of myocardial infarction. In contrast, the Nordic-Baltic Bifurcation Study IV demonstrated that event rates were not significantly different comparing the simple vs. complex strategies in true bifurcation lesions involving a large SB. Fractional flow reserve (FFR) has emerged as a powerful catheter based tool for the functional assessment of a stenosis, but the role of FFR on the long-term outcomes of patients with CBL has not been studied. Given the recent evidence that Tryton stents (a dedicated bifurcation stent) increased event rates, and the lack of benefit from using 2-stent techniques (the Nordic Baltic Bifurcation Study IV) in true CBL, assessing the FFR of the SB seems now of outmost importance, but randomized data are lacking. An intravascular study showed that kissing balloon inflation (KBI) significantly reduced SB stenosis, restored stent lumen at the carina, and expanded stent in the proximal segment. However, a recent randomized study showed no significant benefit of routine KBI. This review highlights current concepts and future perspectives in patients with CBL.

A modified provisional stenting approach to coronary bifurcation lesions: clinical application of the "jailed-balloon technique"

OBJECTIVES

To demonstrate the application of a novel provisional side branch (SB) stenting strategy for coronary bifurcation lesions using a "jailed-balloon" technique (JBT).

BACKGROUND

Adverse cardiac events are higher for percutaneous coronary intervention (PCI) of bifurcation lesions. Recent studies support the use of provisional SB stenting, but a risk of SB closure and a higher rate of target lesion revascularization (TLR) remain important limitations.

METHODS

From December 2007 to August 2010, 100 patients with 102 bifurcation lesions underwent PCI using the JBT. Baseline and postprocedural quantitative coronary angiography (QCA) analysis were performed. Procedural and immediate clinical outcomes were reviewed.

RESULTS

The majority of patients presented with acute coronary syndrome (68%) and had Medina class 1,1,1 bifurcation lesions (91%). TIMI 3 flow was established in 100% of main branch and 99% of SB lesions. QCA revealed preservation of the bifurcation angle after PCI (pre-PCI: 59.6 ± 30.0; post-PCI: 63.3 ± 26.8, P = 0.41). Nine patients (9%) had lesions that required rewiring and two patients (2%) required provisional stenting of the SB. SB loss occurred in one patient (1%). The jailed-balloon or wire was not entrapped during any PCI. One patient (1%) suffered a periprocedural myocardial infarction (MI).

CONCLUSIONS

Provisional stenting of complex coronary bifurcation lesions using a JBT is associated with a high procedural success rate, improved SB patency, and a low rate of immediate cardiac events. Further study is warranted to evaluate the role of JBT in improving long-term clinical outcomes in PCI of complex bifurcation lesions.

Impact of main branch stenting on endothelial shear stress: role of side branch diameter, angle and lesion

In-stent restenosis and stent thrombosis remain clinically significant problems for bifurcation lesions. The objective of this study is to determine the haemodynamic effect of the side branch (SB) on main branch (MB) stenting. We hypothesize that the presence of a SB has a negative effect on MB wall shear stress (WSS), wall shear stress gradient (WSSG) and oscillatory shear index (OSI); and that the bifurcation diameter ratio (SB diameter/MB diameter) and angle are important contributors. We further hypothesized that stent undersizing exaggerates the negative effects on WSS, WSSG and OSI. To test these hypotheses, we developed computational models of stents and non-Newtonian blood. The models were then interfaced, meshed and solved in a validated finite-element package. Stents at bifurcation models were created with 30° and 70° bifurcation angles and bifurcations with diameter ratios of SB/MB = 1/2 and 3/4. It was found that stents placed in the MB at a bifurcation lowered WSS dramatically, while elevating WSSG and OSI. Undersizing the stent exaggerated the decrease in WSS, increase in WSSG and OSI, and disturbed the flow between the struts and the vessel wall. Stenting the MB at bifurcations with larger SB/MB ratios or smaller SB angles (30°) resulted in lower WSS, higher WSSG and OSI. Stenosis at the SB lowered WSS and elevated WSSG and OSI. These findings highlight the effects of major biomechanical factors in MB stenting on endothelial WSS, WSSG, OSI and suggests potential mechanisms for the potentially higher adverse clinical events associated with bifurcation stenting.

A novel stenting technique for coronary artery bifurcation stenosis

A novel stenting technique, using one stent strategy, designed to treat type Medina 1,0,0 coronary bifurcation lesions, is described. The atherosclerotic plaque burden in this category of bifurcation lesions is located in the proximal segment of the main branch (MB) of a coronary bifurcation in which the side branch has a sharp angulation (T- or reverse-shaped) relative to the MB. The advantages of this technique are the accurate placement of the stent tailored to cover solely the bifurcation lesion, shoving the plaque burden away from the side branch ostium during stent expansion and the ability to maintain guide wire access in the branch at highest risk of occlusion obviating the need for more cumbersome and time consuming percutaneous coronary intervention procedure.

Bifurcation disease: what do we know, what should we do?

The percutaneous treatment of coronary bifurcations has moved past an important milestone in that the 1- versus 2-stent debate appears to have been resolved. The provisional approach of implanting one stent on the main branch should be the default approach in most bifurcations lesions. Selection of the most appropriate strategy for an individual bifurcation is important. Some bifurcations require 1 stent, whereas others require the stenting of both branches. Irrespective of whether a 1- or 2-stent strategy is chosen, the results after bifurcation percutaneous coronary intervention (PCI) have dramatically improved. Dedicated bifurcation stents are an exciting new technology that may further simplify the management of bifurcation PCI and change some of these concepts.