Role of Quantitative Flow Ratio in Predicting Future Cardiac Allograft Vasculopathy in Heart Transplant Recipients

BACKGROUND

Coronary angiography is the gold standard for cardiac allograft vasculopathy (CAV) diagnosis, but it usually detects the disease at an advanced stage. We investigated the role of quantitative flow ratio (QFR), a noninvasive tool to identify potentially flow-limiting lesions, in predicting CAV development in heart transplant recipients.

METHODS

Consecutive heart transplant recipients with no evidence of angiographic CAV at baseline coronary angiography were retrospectively included between January 2010 and December 2015, and QFR computation was performed. The relationship between vessel QFR and the occurrence of angiographic vessel-related CAV (≥50% stenosis) was assessed.

RESULTS

One hundred forty-three patients were included and QFR computation was feasible in 241 vessels. The median value of QFR at baseline coronary angiography was 0.98 (interquartile range, 0.94-1.00). During a median follow-up of 6.0 years (interquartile range, 4.6-7.8 years), vessel-related CAV occurred in 25 (10.4%) vessels. Receiver-operating characteristic curve analysis identified a QFR best cutoff of ≤0.95 (area under the curve, 0.81 [95% CI, 0.71-0.90]; P<0.001). QFR≤0.95 was associated with an increased risk of vessel-related CAV (adjusted hazard ratio, 20.87 [95% CI, 5.35-81.43]; P<0.001). In an exploratory analysis, QFR≤0.95 in at least 2 vessels was associated with higher incidence of cardiovascular death or late graft dysfunction (71.4% in recipients with 2-3 vessels affected versus 5.1% in recipients with 0-1 vessels affected, P<0.001).

CONCLUSIONS

In a cohort of heart transplant recipients, QFR computation at baseline coronary angiography may be a safe and reliable tool to predict vessel-related CAV and clinical outcomes at long-term follow-up.

Angio-Based Fractional Flow Reserve, Functional Pattern of Coronary Artery Disease, and Prediction of Percutaneous Coronary Intervention Result: a Proof-of-Concept Study

PURPOSE

Wire-based coronary physiology pullback performed before percutaneous coronary intervention (PCI) discriminates coronary artery disease (CAD) distribution and extent, and is able to predict functional PCI result. No research investigated if quantitative flow ratio (QFR)-based physiology assessment is able to provide similar information.

METHODS

In 111 patients (120 vessels) treated with PCI, QFR was measured both before and after PCI. Pre-PCI QFR trace was used to discriminate functional patterns of CAD (focal, serial lesions, diffuse disease, combination). Functional CAD patterns were identified analyzing changes in the QFR virtual pullback trace (qualitative method) or after computation of the QFR virtual pullback index (QVP_index) (quantitative method). QVP_index calculation was based on the maximal QFR drop over 20 mm and the length of epicardial coronary segment with QFR most relevant drop. Then, the ability of the different functional patterns of CAD to predict post-PCI QFR value was tested.

RESULTS

By qualitative method, 51 (43%), 20 (17%), 15 (12%), and 34 (28%) vessels were classified as focal, serial focal lesions, diffuse disease, and combination, respectively. QVP_index values >0.71 and ≤0.51 predicted focal and diffuse patterns, respectively. Suboptimal PCI result (post-PCI QFR value ≤0.89) was present in 22 (18%) vessels. Its occurrence differed across functional patterns of CAD (focal 8% vs. serial lesions 15% vs. diffuse disease 33% vs. combination 29%, p=0.03). Similarly, QVP_index was correlated with post-PCI QFR value (r=0.62, 95% CI 0.50-0.72).

CONCLUSION

Our results suggest that functional patterns of CAD based on pre-PCI QFR trace can predict the functional outcome after PCI.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov , number NCT02811796. Date of registration: June 23, 2016.

Transradial access versus transfemoral access: a comparison of outcomes and efficacy in reducing hemorrhagic events

Introduction: The radial artery is currently the most widely used access site for PCI procedures both acute and stable patient settings. Thanks to advantages in pharmacological therapy as well as in interventional devices, the rate of ischemic complications following PCI has significantly decreased. Nevertheless, this has been counterbalanced by an increased risk of periprocedural and late bleeding event, that can occur both at access and non-access sites. Choice of access site for PCI is of paramount importance to reduce the risk of access-related bleeding events. Areas covered: The aim of this review is to provide an overview of the actual available evidence comparing the transradial versus transfemoral approach to reduce hemorrhagic events. The most robust evidence comes from large randomized trials, partly also from observational registries, which compared the transradial and transfemoral approach. Expert opinion: Results show that radial access has proved to be decisive in reducing the incidence of hemorrhagic events. Furthermore, it showed a significant reduction in mortality and AKI compared to transfemoral access. However, increased experience in the use of the radial approach has led to less practice in the use of the femoral approach, which may be useful in cases of emergency, complications or inability to use the radial artery.

Quantitative Flow Ratio Identifies Nonculprit Coronary Lesions Requiring Revascularization in Patients With ST-Segment-Elevation Myocardial Infarction and Multivessel Disease

BACKGROUND

The nonculprit lesion (NCL) management in ST-segment-elevation myocardial infarction patients with multivessel disease is debated. We sought to assess whether quantitative flow ratio (QFR), a noninvasive tool to identify potentially flow-limiting lesions, may be reliable in this scenario.

METHODS AND RESULTS

The present proof-of-concept study is based on a 3-step process: (1) identification of the QFR reproducibility in NCLs assessment (cohort A, n=31); (2) prospective validation of QFR diagnostic accuracy in respect to fractional flow reserve (cohort B, n=45); and (3) investigation of long-term clinical outcomes of NCLs stratified according to QFR (cohort C, n=110). A blinded core laboratory computed QFR values for all NCLs. Cohort A showed a good correlation and agreement between QFR values at index (acute) and at staged (subacute, 3-4 days later) procedures (r=0.98; 95% confidence interval, 0.96-0.99; mean difference, 0.004 [-0.027 to 0.34]). The inter-rater agreement was κ=0.9. In cohort B, fractional flow reserve and QFR identified 16 (33%) and 17 (35%) NCLs potentially flow limiting. Sensitivity, specificity, negative, and positive predictive values were 88%, 97%, 94%, and 94%. The area under the receiver operating characteristics curve was 0.96 (95% confidence interval, 0.89-0.99). Finally, in cohort C, we identified 110 ST-segment-elevation myocardial infarction patients where at least 1 NCL was left untreated. Patients with NCLs showing a QFR value ≤0.80 were at higher risk of adverse events (hazard ratio, 2.3; 95% confidence interval, 1.2-4.5; P=0.01).

CONCLUSIONS

In a limited and selected study population, our study showed that QFR computation may be a safe and reliable tool to guide coronary revascularization of NCLs in ST-segment-elevation myocardial infarction patients.

[Updated SICI-GISE position paper on institutional and operator requirements for transcatheter aortic valve implantation]

Transcatheter aortic valve implantation (TAVI) has revolutionized the management of patients with symptomatic severe aortic stenosis and has become the standard of care for inoperable patients and the preferred therapy for those at increased surgical risk with peculiar clinical and anatomic features. Technology advances, growing experience and accumulating data prompted the update of the 2011 Italian Society of Interventional Cardiology (SICI-GISE) position paper on institutional and operator requirements to perform TAVI. The main objective of this document is to provide a guidance to assess the potential of institutions and operators to initiate and maintain an efficient TAVI program.

Diagnostic Performance of In-Procedure Angiography-Derived Quantitative Flow Reserve Compared to Pressure-Derived Fractional Flow Reserve: The FAVOR II Europe-Japan Study

Background

Quantitative flow ratio (QFR) is a novel modality for physiological lesion assessment based on 3‐dimensional vessel reconstructions and contrast flow velocity estimates. We evaluated the value of online QFR during routine invasive coronary angiography for procedural feasibility, diagnostic performance, and agreement with pressure‐wire–derived fractional flow reserve (FFR) as a gold standard in an international multicenter study.

Methods and Results

FAVOR II E‐J (Functional Assessment by Various Flow Reconstructions II Europe‐Japan) was a prospective, observational, investigator‐initiated study. Patients with stable angina pectoris were enrolled in 11 international centers. FFR and online QFR computation were performed in all eligible lesions. An independent core lab performed 2‐dimensional quantitative coronary angiography (2D‐QCA) analysis of all lesions assessed with QFR and FFR. The primary comparison was sensitivity and specificity of QFR compared with 2D‐QCA using FFR as a reference standard. A total of 329 patients were enrolled. Paired assessment of FFR, QFR, and 2D‐QCA was available for 317 lesions. Mean FFR, QFR, and percent diameter stenosis were 0.83±0.09, 0.82±10, and 45±10%, respectively. FFR was ≤0.80 in 104 (33%) lesions. Sensitivity and specificity by QFR was significantly higher than by 2D‐QCA (sensitivity, 86.5% (78.4–92.4) versus 44.2% (34.5–54.3); P<0.001; specificity, 86.9% (81.6–91.1) versus 76.5% (70.3–82.0); P=0.002). Area under the receiver curve was significantly higher for QFR compared with 2D‐QCA (area under the receiver curve, 0.92 [0.89–0.96] versus 0.64 [0.57–0.70]; P<0.001). Median time to QFR was significantly lower than median time to FFR (time to QFR, 5.0 minutes [interquartile range, –6.1] versus time to FFR, 7.0 minutes [interquartile range, 5.0–10.0]; P<0.001).

Conclusions

Online computation of QFR in the catheterization laboratory is clinically feasible and is superior to angiographic assessment for evaluation of intermediary coronary artery stenosis using FFR as a reference standard.

Clinical Trial Registration

URL: https://www.clinicaltrials.gov. Unique identifier: NCT02959814.

[SICI-GISE commuNity CAmpania survey doNna TAVI (INCANTA): perioperative and short-term outcome of transcatheter aortic valve implantation in women]

BACKGROUND

Nowadays the prognostic role of gender as a relevant factor after transcatheter aortic valve implantation (TAVI) is still unfair, since available data in the literature are few and uneven. The aim of this survey was to collect acute and 30-day safety and efficacy clinical data in high- and intermediate-risk women, who underwent TAVI with new-generation devices, in the Campania Region.

METHODS

All medium and high-volume TAVI centers in Campania have been invited to fulfill an online, ad-hoc questionnaire, collecting pre-, peri- and post-procedural data concerning female patients, treated between January and December 2016.

RESULTS

331 women (representing the 61% of the overall population treated; mean age 83 ± 7 years) underwent TAVI in the participating Campania centers. Age >80 years (72%), high surgical risk score (63%) and frailty (55%) were found to be the top three reasons for the TAVI choice. Overall, 95% of the procedures were performed by transfemoral approach with local anesthesia; the remaining 5% (16 cases) were conducted via transapical (14, 4%) and transaortic (2, 1%) accesses, under general anesthesia. Edwards Sapien 3 (Edwards Lifesciences, Irvine, CA, USA) and Medtronic Evolut R (Medtronic Inc., Minneapolis, MN, USA) were the most frequently implanted valves (146, 44% and 132, 43%, respectively). The questioned Centers reported a mean length of hospital stay of 5.5 ± 1.1 days, 1.6 ± 0.37 of which in a cardiac care unit. The most prevalent in-hospital complication was pacemaker implantation (15%), followed by life-threatening vascular complications (3%). The 30-day VARC-2 composite endpoint occurred in 7% of cases, all-cause death in 4%, and stroke in 1%.

CONCLUSIONS

This survey, the first representative of women undergoing TAVI in Campania, appears to confirm the good safety and efficacy profile of this procedure, also in the high- and intermediate-risk settings, probably favored by a prevalent use of new-generation devices and a low rate prevalence of significant patient comorbidities.

Prognostic Factors in Patients With Stemi Undergoing Primary PCI in the Clopidogrel Era: Role of Dual Antiplatelet Therapy at Admission and the Smoking Paradox on Long-Term Outcome

BACKGROUND

Several clinical and laboratory variables have an impact on the prognosis of STEMI patients undergoing PPCI; however, little is known about the role of ongoing DAPT at the time of the event and the smoking status as prognostic factors affecting the outcome of these patients.

METHODS AND RESULTS

Seven-hundred and thirteen consecutive STEMI patients undergoing PPCI, admitted to the S. Anna and S. Sebastiano Hospital (Caserta, Italy) and to the OLV Clinic (Aalst, Belgium), between March 2009 and December 2011, were retrospectively enrolled. Rescue PCI was the only exclusion criterion. Primary end-point was the combination of death for all causes, re-infarction, stroke, and target lesion revascularization (TLR). Patients already on DAPT at admission (26.4%) showed a significant increase in the event rate at univariate analysis (HR 2.34, CI 1.62-3.75, P < 0.05), while current smokers (56.5%) had a lower event rate, as compared to non-smokers (HR 0.67, CI 0.46-0.96, P < 0.05). In smoking patients already on DAPT at admission, a lower event rate was observed than in non-smoking patients on DAPT. Although, patients already on DAPT had a higher-risk profile (renal impairment, ongoing statin treatment, ST resolution <50%, and Killip class >1 were more frequently present than in patients not on DAPT), Cox regression analysis confirmed that both DAPT (HR 1.74, 95%CI 1.20-2.53, P < 0.01) and smoking status (HR 0.69, 95%CI 0.48-1.00, P < 0.05) retained their statistical significance, as they and were significantly associated with a worse and a better outcome, respectively, underlying their role as independent prognostic factors.

CONCLUSIONS

Not being a current smoker and ongoing DAPT at admission, in patients with STEMI undergoing PPCI, represent independent negative prognostic value.

Simplifying clinical risk prediction for percutaneous coronary intervention of bifurcation lesions: the case for the ACEF (age, creatinine, ejection fraction) score

AIMS

We aimed to appraise the predictive accuracy of a novel and user-friendly risk score, the ACEF (age, creatinine, ejection fraction), in patients undergoing PCI for coronary bifurcations.

METHODS AND RESULTS

A multicentre, retrospective study was conducted enrolling consecutive patients undergoing bifurcation PCI between January 2002 and December 2006 in 22 Italian centres. Patients with complete data to enable computation of the ACEF score were divided into three groups according to tertiles of ACEF score. The primary endpoint was 30-day mortality. The discrimination of the ACEF score as a continuous variable was also appraised with area under the curve (AUC) of the receiver-operating characteristic. A total of 3,535 patients were included: 1,119 in the lowest tertile of ACEF score, 1,190 in the mid tertile, and 1,153 in the highest tertile. Increased ACEF score was associated with significantly different rates of 30-day mortality (0.1% in the lowest tertile vs. 0.5% in the mid tertile and 3.0% in the highest tertile, p<0.001), with similar differences in myocardial infarction (0.3% vs. 0.7% and 1.8%, p<0.001) and major adverse cardiac events (MACE, 0.5% vs. 1.2% and 4.3%, p<0.001). After an average follow-up of 24.4±15.1 months, increased ACEF score was still associated with a higher rate of all-cause death (1.3% vs. 2.4% and 11.0%, p<0.001), cardiac death (0.9% vs. 1.4% and 7.2%, p<0.001), myocardial infarction (3.4% vs. 2.7% and 5.7%, p<0.001), MACE (13.6% vs. 15.9% and 22.3%, p<0.001), and stent thrombosis (2.3% vs. 1.8% and 5.0%, p<0.001). Discrimination of ACEF score was satisfactory for 30-day mortality (AUC=0.82 [0.77-0.87], p<0.001), 30-day MACE (AUC=0.73 [0.67-0.78], p<0.001), long-term mortality (AUC=0.77 [0.74-0.81], p<0.001), and moderate for long-term MACE (AUC=0.60 [0.57-0.62], p<0.001).

CONCLUSIONS

The simple and extremely user-friendly ACEF score can accurately identify patients undergoing PCI for coronary bifurcation lesions at high risk of early fatal or non-fatal complications, as well as long-term fatality.

Early and long-term outlook of percutaneous coronary intervention for bifurcation lesions in young patients

BACKGROUND

Coronary artery disease is most common in older patients, but may occur in younger subjects. The outlook of young patients after percutaneous coronary intervention (PCI) of challenging lesion subsets such as coronary bifurcations, is not established. We thus aimed to appraise the early and long-term results of PCI for bifurcations in young patients.

METHODS

A multicenter, retrospective study was conducted enrolling consecutive patients undergoing bifurcation PCI between 2002 and 2006 in 22 Italian centers. Patients were divided in 2 groups: age ≤ 45 years, and age > 45 years. The primary end-point was long-term rate of major adverse cardiac events (MACE).

RESULTS

4,314 patients were included: 195 (4.5%) in the younger group, and 4119 (95.5%) in the older group. 30-day outcomes did not show significant differences in MACE rates, with 1.0% in the ≤ 45 years group and 2.1% in the >45 years group (p=0.439), with death in 0.5% and 1.2% (p=0.388). At long-term follow-up (24.4 ± 15.1 months), younger patients showed similar rates of MACE, (12.8% vs. 16.6%, p=0.161), myocardial infarction (3.1% vs. 3.7%, p=0.633), target lesion revascularization (11.3% vs. 12.5%, p=0.627), or stent thrombosis (1.5% vs. 2.8%, p=0.294), despite an increased risk of death in older patients (1.0% vs. 5.0%, p=0.012). Even at extensive multivariable analysis, younger patients still faced a similar risk of MACE (HR=0.78 [0.48-1.27], p=0.318).

CONCLUSIONS

Despite their low age, young patients undergoing PCI for bifurcation face a significant risk of early and late non-fatal adverse events. Thus, they should not be denied careful medical management and follow-up.

Impact of drug-eluting stents and diabetes mellitus in patients with coronary bifurcation lesions: a survey from the Italian Society of Invasive Cardiology

BACKGROUND

We investigated the long-term impact of different stent types and diabetes mellitus (DM) in patients undergoing percutaneous coronary intervention (PCI) of bifurcation lesions, based on a large multicenter survey endorsed by the Italian Society of Invasive Cardiology.

METHODS AND RESULTS

Relative benefits of drug eluting stent (DES) over bare metal stent (BMS) in patients with (n=1049) and without (n=3020) DM were analyzed with extensive multivariable adjustment. At 3 years, stenting with DES was associated with lower adjusted risk of major adverse cardiac events (MACE, adjusted hazard ratio [HR] 0.27, 95% confidence interval [CI] 0.15 to 0.49, P<0.001), cardiac death, and target lesion revascularization in DM patients but failed to demonstrate any significant benefit in patients without DM.

CONCLUSIONS

In a large observational registry with admitted potential for selection bias and residual confounding, DES in DM patients with coronary bifurcation lesions were associated with improved outcomes in terms of MACE, cardiac death, and repeat revascularization at long-term follow up. These figures were not replicated in non-DM subjects.