Instantaneous Wave-Free Ratio for the Assessment of Intermediate Left Main Coronary Artery Stenosis: Correlations With Fractional Flow Reserve/Intravascular Ultrasound and Prognostic Implications: The iLITRO-EPIC07 Study

BACKGROUND

There is little information available on agreement between fractional flow reserve (FFR) and instantaneous wave-free ratio (iFR) in left main coronary artery (LMCA) intermediate stenosis. Besides, several meta-analyses support the use of FFR to guide LMCA revascularization, but limited information is available on iFR in this setting. Our aims were to establish the concordance between FFR and iFR in intermediate LMCA lesions, to evaluate with intravascular ultrasound (IVUS) in cases of FFR/iFR discordance, and to prospectively validate the safety of deferring revascularization based on a hybrid decision-making strategy combining iFR and IVUS.

METHODS

Prospective, observational, multicenter registry with 300 consecutive patients with intermediate LMCA stenosis who underwent FFR and iFR and, in case of discordance, IVUS and minimal lumen area measurements. Primary clinical end point was a composite of cardiovascular death, LMCA lesion-related nonfatal myocardial infarction, or unplanned LMCA revascularization.

RESULTS

FFR and iFR had an agreement of 80% (both positive in 67 and both negative in 167 patients); in case of disagreement (31 FFR+/iFR- and 29 FFR-/iFR+) minimal lumen area was ≥6 mm² in 8.7% of patients with FFR+ and 14.6% with iFR+. Among the 300 patients, 105 (35%) underwent revascularization and 181 (60%) were deferred according to iFR and IVUS. At a median follow-up of 20 months, major adverse cardiac events incidence was 8.3% in the defer group and 13.3% in the revascularization group (hazard ratio, 0.71 [95% CI 0.30-1.72]; P=0.45).

CONCLUSIONS

In patients with intermediate LMCA stenosis, a physiology-guided treatment decision is feasible either with FFR or iFR with moderate concordance between both indices. In case of disagreement, the use of IVUS may be useful to indicate revascularization. Deferral of revascularization based on iFR appears to be safe in terms of major adverse cardiac events.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT03767621.

Design and rationale for a real-world prospective, multicenter registry of myocardial revascularization failure and secondary revascularization: The REVASEC study

AIM

To investigate key aspects of the problem of myocardial revascularization failure (MRF) and repeat or secondary myocardial revascularization (SR) in contemporary practice.

METHODS

The registry of secondary revascularization (REVASEC) is an investigator-initiated, multicenter, prospective registry enhanced with data monitoring and independent event adjudication (ClinicalTrials.govNCT03349385). It includes patients with prior revascularization referred to coronary angiography for suspected MRF with broad inclusion criteria. The main objectives are to describe the characteristics of patients with prior revascularization referred for repeat angiography, to describe and the rate and mechanisms of MRF (stent or graft failure, coronary artery disease progression or residual coronary artery disease); to evaluate the management including medical treatment and SR of these patients; and to assess the prognosis according to the outlined causative mechanisms. The registry has one year follow up for the primary endpoint (Patient-oriented composite endpoint including all-cause death, any myocardial infarction or any new unplanned revascularization according to subsets of MRF), but extended follow-up will be carried out up to 5 years.

CONCLUSION

The REVASEC Registry will provide updated data on the characteristics, patterns of treatment, and 1-year outcomes of patients with MRF and SR in contemporary clinical practice.

Comparison of dual-axis rotational coronary angiography (XPERSWING) versus conventional technique in routine practice

INTRODUCTION AND OBJECTIVES

Coronary angiography is the gold standard for the study of coronary artery disease. This technique requires several orthogonal projections. Rotational angiography is a new technique which involves pre-set rotation of the X-ray tube around the patient and allows visualization of each coronary artery in different views, using a single contrast injection. The purpose of this study was to compare conventional coronary angiography (A) vs rotational angiography (B), focusing on radiation dose, amount of contrast administered, and total procedure time for both diagnostic and therapeutic percutaneous coronary interventions.

METHODS

Prospective study of 104 consecutive patients undergoing coronary angiography who were randomized to one of these techniques.

RESULTS

We found a significant reduction in the amount of contrast administered (A vs B, 93.1 [41.7] vs 50.9 [14.7] mL; P<.0001) and radiation exposure (27.6 [11.5] vs 18 [6.4] mGycm(2); P<.0001). A significant increase in total procedure time was noted in the rotational angiography arm. However, when only the last 50 patients were analyzed, we found no difference in procedure time between the groups, probably related to the learning curve of the operators. Angioplasty was performed in 29 patients in group A and 28 patients in group B. Contrast reduction was maintained in the rotational angiography group compared to the conventional technique (A vs B, 335.1 [192.1] vs 238.5 [114.4] mL; P=.02).

CONCLUSIONS

The rotational angiography technique leads to a significant decrease in radiation exposure and contrast dose administered for diagnostic procedures when compared to conventional coronary angiography. In patients who undergo percutaneous coronary intervention, contrast reduction remains significant.