Practical Application of Coronary Physiologic Assessment: Asia-Pacific Expert Consensus Document: Part 2

Coronary physiologic assessment is performed to measure coronary pressure, flow, and resistance or their surrogates to enable the selection of appropriate management strategy and its optimization for patients with coronary artery disease. The value of physiologic assessment is supported by a large body of clinical data that has led to major recommendations in all practice guidelines. This expert consensus document aims to convey practical and balanced recommendations and future perspectives for coronary physiologic assessment for physicians and patients in the Asia-Pacific region, based on updated information in the field that includes both wire- and image-based physiologic assessment. This is Part 2 of the whole consensus document, which provides theoretical and practical information on physiologic indexes for specific clinical conditions and patient statuses.

Physiological Approach for Coronary Artery Bifurcation Disease: Position Statement by Korean, Japanese, and European Bifurcation Clubs

Coronary artery bifurcation lesions are frequently encountered in cardiac catheterization laboratories and are associated with more complex procedures and worse clinical outcomes than nonbifurcation lesions. Therefore, anatomical and physiological assessment of bifurcation lesions before, during, and after percutaneous coronary intervention is of paramount clinical importance. Physiological assessment can help interventionalists appreciate the hemodynamic significance of coronary artery disease and guide ischemia-directed revascularization. However, it is important to understand that the physiological approach for bifurcation disease is more important than simply using physiological indexes for its assessment. This joint consensus document by the Korean, Japanese, and European bifurcation clubs presents the concept of a physiological approach for coronary bifurcation lesions, as well as current knowledge, practical tips, pitfalls, and future directions of applying physiological indexes in bifurcation percutaneous coronary intervention. This document aims to guide interventionalists in performing appropriate physiology-based assessments and treatment decisions for coronary bifurcation lesions.

Outcomes Among Patients Undergoing Distal Left Main Percutaneous Coronary Intervention

BACKGROUND

Distal left main (LM) coronary artery bifurcation disease increases percutaneous coronary intervention (PCI) procedural complexity and is associated with worse outcomes than isolated ostial/shaft disease. The optimal treatment strategy for distal LM disease is undetermined. We sought to determine whether outcomes after PCI of LM distal bifurcation lesions are influenced by treatment with a provisional 1-stent versus planned 2-stent technique, and if so, whether such differences are conditioned by the complexity of the LM bifurcation lesion.

METHODS AND RESULTS

The clinical and angiographic characteristics, procedural methods and outcomes, and clinical events through 3-year follow-up were compared in patients undergoing distal LM PCI with a 1-stent provisional versus planned 2-stent technique in the EXCEL trial (Evaluation of XIENCE Versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization). Among 529 patients undergoing planned distal LM PCI, 344 (65.0%) and 185 (35.0%) were treated with intended 1-stent provisional and planned 2-stent techniques, respectively. The primary composite end point rate of death, myocardial infarction, or stroke at 3 years was significantly lower in patients treated with the provisional 1-stent versus planned 2-stent method (14.1% versus 20.7%; adjusted hazard ratio, 0.55; 95% CI, 0.35-0.88; P=0.01), driven by differences in cardiovascular death (3.3% versus 8.3%, P=0.01) and myocardial infarction (7.7% versus 12.8%, P=0.06). The 3-year rate of ischemia-driven revascularization of the LM complex was also lower in the provisional group (7.2% versus 16.3%, P=0.001). In 342 patients with distal LM bifurcation disease that did not involve both major side branch vessels, the 3-year primary end point was lower with a provisional 1-stent versus planned 2-stent technique (13.8% versus 23.3%, P=0.04), whereas no significant difference was present in 182 patients with distal LM bifurcation disease that did involve both side branch vessels (14.3% versus 19.2%, P=0.36).

CONCLUSIONS

Among patients with distal LM bifurcation disease in the EXCEL trial randomized to PCI, 3-year adverse outcomes were worse with planned 2-stent treatment compared with a provisional 1-stent approach, a difference that was confined to patients without major involvement of both LM side branch vessels.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov . Unique identifier: NCT01205776.

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.