Treatment of Bifurcation Lesions: Has DK Crush"ed" the Competition?

PURPOSE

This paper reviews the double-kiss crush (DK crush) technique in coronary artery bifurcation lesions. The technical aspects of the procedure and the clinical data supporting its use are summarized.

RECENT FINDINGS

Randomized studies support the adoption of DK technique in complex bifurcation lesions for both left main and non-left-main lesions. For true bifurcation lesions, DK crush may become the default technique for lesions in which the side-branch disease is complex and long. Optimal technique is essential for obtaining the clinical outcomes noted in the DKCRUSH randomized studies.

Intracoronary electrocardiogram to guide percutaneous interventions in coronary bifurcations - a proof of concept: the FIESTA (Ffr vs. IcEcgSTA) study

AIMS

The aim of this study was to determine the accuracy of the intracoronary electrocardiogram (icECG) to detect ischaemia during bifurcation lesion percutaneous coronary intervention (PCI) with fractional flow reserve (FFR) as a reference.

METHODS AND RESULTS

Patients with significant bifurcation lesions defined as FFR ≤0.80 were included. FFR and icECG were performed in the main vessel (MV) and side branch (SB) before and after provisional stenting. icECG was recorded with an uninsulated proximal wire end connected to a unipolar lead. The diagnostic accuracy of the icECG for the detection of ischaemia in the SB after MV stenting was determined with FFR as a reference. Overall, 37 patients were included. Seventeen bifurcations had an SB FFR ≤0.80 after MV stenting and 20 patients had an ST-segment elevation on the icECG. There was significant correlation between SB FFR and ST-segment elevation on the icECG (r=-0.533, p<0.001). The diagnostic accuracy of icECG ST-elevation to detect functionally significant SB stenosis revealed an AUC of 0.71 (95% CI: 0.64-0.80) with a sensitivity of 88% and specificity of 75% with a positive predictive value of 75% and negative predictive value of 88%. Neither SB FFR nor icECG correlated with SB percent diameter stenosis after MV stenting.

CONCLUSIONS

Intracoronary ECG has a good ability to predict functionally significant stenosis at the SB after MV stenting during bifurcation PCI. This method provides a novel strategy to assess the significance of an SB lesion without the need of a pressure wire.

Benefit of a new provisional stenting strategy, the re-proximal optimisation technique: the rePOT clinical study

AIMS

A new coronary bifurcation provisional stenting technique without kissing balloon, rePOT, associating the proximal optimisation technique (POT), side branch inflation and final POT, showed excellent mechanical results in a bench test. The present study sought to use optical coherence tomography (OCT) to quantify the mechanical results of rePOT in vivo in a large patient sample with complex coronary bifurcations.

METHODS AND RESULTS

A total of 106 patients with coronary bifurcations were included in a multicentre prospective registry (left main, 40.6%; true Medina bifurcation, 39.6%). Three OCT runs were performed, at baseline, just after stent implantation and after the complete rePOT sequence, quantifying global malapposition, side branch obstruction (SBO), and various geometric arterial criteria. RePOT was completed systematically. RePOT significantly reduced global strut malapposition from 18.9±13.4% just after stent implantation to 3.2±3.9% (p<0.05), residual SBO from 44.3±12.9% to 17.0±14.3% (p<0.05), and ellipticity index from 1.19±0.11 to 1.13±0.12 (p<0.05). Exhaustive six-month follow-up found only one mother-vessel target lesion revascularisation.

CONCLUSIONS

This clinical study of a large sample of complex coronary bifurcations with OCT analysis showed the benefit of the rePOT sequence in provisional stenting, replicating in vivo the excellent in vitro geometric results previously reported, and confirming ease of implementation and medium-term safety.

Percutaneous coronary intervention in left main coronary artery disease: the 13th consensus document from the European Bifurcation Club

The 2017 European Bifurcation Club (EBC) meeting was held in Porto (Portugal) and allowed a multidisciplinary international faculty to review and discuss the latest data collected in the field of coronary bifurcation interventions. In particular, the topic of percutaneous coronary intervention (PCI) on left main coronary artery (LM) disease was highlighted as a contemporary priority. Herein, we summarise the key LM anatomy features, the diagnostic modalities and available data that are relevant for a patient's procedural management. Since the clinical outcomes of patients undergoing PCI on LM disease may depend on both PCI team organisation and PCI performance, the optimal catheterisation laboratory set-up and the rationales for device and technique selection are critically reviewed. The best lesion preparation modalities, the different DES implantation technique choices and the strategies to be considered during PCI on unprotected LM for optimal PCI results are reviewed step by step.

Understanding the Coronary Bifurcation Stenting

Coronary bifurcation stenting is still complex and associated with a high risk of stent thrombosis and restenosis even with contemporary techniques. Although provisional approach has been proved to be the standard strategy of treatment, There is still lack of evidences for multiple steps of the procedure. For so many years we have been focused on the optimization of side branch (SB), but the clinical outcome is mostly dependent on the main vessel (MV) stenting. The optimal expansion of MV stent without the compromise of SB is the ultimate goal to achieve in the coronary bifurcation stenting. Understanding the anatomy and physiology of coronary bifurcation lesion should be the most important step to this goal. The relationship of vessel diameter between branches and the anatomical and functional significance of plaque shift and carina shift are two most important concepts to understand. They are the science behind the predictors of SB occlusion, and the rationale of proximal optimization technique and final kissing ballooning. This specific review will be devoted to review those concepts as well as clinical evidences to support them.