Fractional Flow Reserve Versus Instantaneous Wave-Free Ratio in Assessment of Lesion Hemodynamic Significance and Explanation of their Discrepancies. International, Multicenter and Prospective Trial: The FiGARO Study.

Background The FiGARO (FFR versus iFR in Assessment of Hemodynamic Lesion Significance, and an Explanation of Their Discrepancies) trial is a prospective registry searching for predictors of fractional flow reserve/instantaneous wave-free ratio (FFR/iFR) discrepancy. Methods and Results FFR/iFR were analyzed using a Verrata wire, and coronary flow reserve was analyzed using a Combomap machine (both Philips-Volcano). The risk polymorphisms for endothelial nitric oxide synthase and for heme oxygenase-1 were analyzed. In total, 1884 FFR/iFR measurements from 1564 patients were included. The FFR/iFR discrepancy occurred in 393 measurements (20.9%): FFRp (positive)/iFRn (negative) type (264 lesions, 14.0%) and FFRn/iFRp (129 lesions, 6.8%) type. Coronary flow reserve was measured in 343 lesions, correlating better with iFR (R=0.56, P<0.0001) than FFR (R=0.36, P<0.0001). The coronary flow reserve value in FFRp/iFRn lesions (2.24±0.7) was significantly higher compared with both FFRp/iFRp (1.39±0.36), and FFRn/iFRn lesions (1.8±0.64, P<0.0001). Multivariable logistic regression analysis confirmed (1) sex, age, and lesion location in the right coronary artery as predictors for FFRp/iFRn discrepancy; and (2) hemoglobin level, smoking, and renal insufficiency as predictors for FFRn/iFRp discrepancy. The FFRn/iFRp type of discrepancy was significantly more frequent in patients with both risk types of polymorphisms (endothelial nitric oxide synthaser+heme oxygenase-1r): 8 patients (24.2%) compared with FFRp/iFRn type of discrepancy: 2 patients (5.9%), P=0.03. Conclusions Predictors for FFRp/iFRn discrepancy were sex, age, and location in the right coronary artery. Predictors for FFRn/iFRp were hemoglobin level, smoking, and renal insufficiency. The risk type of polymorphism in endothelial nitric oxide synthase and heme oxygenase-1 genes was more frequently found in patients with FFRn/iFRp type of discrepancy. Registration URL: https://clinicaltrials.gov; Unique identifier: NCT03033810.

The Effect of Diabetes on Prognosis Following Myocardial Infarction Treated with Primary Angioplasty and Potent Antiplatelet Therapy.

PURPOSE: To investigate the prognostic significance of diabetes mellitus (DM) in patients with high risk acute myocardial infarction (AMI) treated with primary percutaneous coronary intervention (pPCI) in the era of potent antithrombotics. METHODS: Data from 1230 ST-segment elevation myocardial infarction (STEMI) patients enrolled in the PRAGUE-18 (prasugrel vs. ticagrelor in pPCI) study were analyzed. Ischemic and bleeding event rates were calculated for patients with and without diabetes. The independent impact of diabetes on outcomes was evaluated after adjustment for outcome predictors. RESULTS: The prevalence of DM was 20% (N = 250). Diabetics were older and more often female. They were more likely to have hypertension, hyperlipoproteinemia, multivessel coronary disease and left main disease, and be obese. The primary net-clinical endpoint (EP) containing death, spontaneous nonfatal MI, stroke, severe bleeding, and revascularization at day 7 occurred in 6.1% of patients with, and in 3.5% of patients without DM (HR 1.8; 95% CI 0.978-3.315; P = 0.055). At one year, the key secondary endpoint defined as cardiovascular death, spontaneous MI, or stroke occurred in 8.8% with, and 5.5% without DM (HR 1.621; 95% CI 0.987-2.661; P = 0.054). In those with DM the risk of total one-year mortality (6.8% vs. 3.9% (HR 1.773; 95% CI 1.001-3.141; P = 0.047)) and the risk of nonfatal reinfarction (4.8% vs. 2.2% (HR 2.177; 95% CI 1.077-4.398; P = 0.026)) were significantly higher compared to in those without DM. There was no risk of major bleeding associated with DM (HR 0.861; 95% CI 0.554-1.339; P = 0.506). In the multivariate analysis, diabetes was independently associated with the one-year risk of reinfarction (HR 2.176; 95% Confidence Interval, 1.055-4.489; p = 0.035). CONCLUSION: Despite best practices STEMI treatment, diabetes is still associated with significantly worse prognoses, which highlights the importance of further improvements in the management of this high-risk population.

Endothelial dysfunction assessed by digital tonometry and discrepancy between fraction flow reserve and instantaneous wave free ratio.

Background: We tested whether the level of endothelial dysfunction assessed by digital tonometry, and expressed as reactive hyperemia index (RHI), is related to occurrences of a discrepancy between fractional flow reserve (FFR) and the instantaneous wave free ratio (iFR) (ClinicalTrials.gov identifier: NCT03033810).Methods: We examined patients with coronary stenosis in the range of 40-70%, assessed by both FFR and iFR (system Philips-Volcano) for stable angina. We included consecutive patients with FFR and iFR in one native coronary artery, and who had had no previous intervention.Results: We included 138 patients. Out of those, 24 patients (17.4%) had a negative FFR (with an FFR value >0.8) and positive iFR (with a iFR value ≤0.89) - designated the FFRn/iFRp discrepancy group, and 22 patients (15.9%) had a positive FFR (≤0.8) and negative iFR (>0.89) - designated the FFRp/iFRn discrepancy. RHI was higher in the discrepancy groups compared the group without discrepancy (1.73 ± 0.79 vs. 1.48 ± 0.50, p = 0.025). However, this finding was not confirmed in multivariant logistic regression analyses. Patients with any type of discrepancy differed from the agreement group by having a higher occurrence of diabetes mellitus [9 patients (21.4%) vs. 36 patients (39.6%), p = 0.029], active smoking (23 patients or 54.8% vs. 26 patients or 28.6%, p = 0.003) and lower use of calcium channel blockers (9 patients, 21.4%, vs. 43 patients, 46.7%, p = 0.004).Conclusion: The presence of endothelial dysfunction can be associated with a discrepancy in FFR/iFR. However, RHI correlated with risk factors of atherosclerosis, not with FFR or iFR.

Incidence, treatment strategies and outcomes of acute coronary syndrome with and without ongoing myocardial ischaemia: results from the CZECH-3 registry.

BACKGROUND: Patients with acute coronary syndrome with signs of ongoing myocardial ischaemia at first medical contact should be indicated for immediate invasive treatment. AIM: To assess the incidence, treatment strategies and outcomes of acute coronary syndrome in a large unselected cohort of patients with respect to the signs of ongoing myocardial ischaemia. METHODS: The CZECH-3 registry included 1754 consecutive patients admitted for suspected acute coronary syndrome to 43 hospitals during a 2-month period in the autumn of 2015. Acute coronary syndrome with ongoing myocardial ischaemia was defined by the presence of persistent/recurrent chest pain/dyspnoea and at least one of the following: persistent ST-segment elevation or depression, bundle branch block, haemodynamic or electric instability due to suspected ischaemia. Major adverse cardiac events (death, reinfarction, stroke, unexpected revascularisation, stent thrombosis) and severe bleeding according to Bleeding Academic Research Consortium criteria were evaluated at 30 days. RESULTS: Acute coronary syndrome was ruled out during the hospital stay in 434 (24.7%) patients. Out of 1280 patients with confirmed acute coronary syndrome, 732 (57%) had clinical signs of ongoing myocardial ischaemia at first medical contact. Coronary angiography was performed in 94.7% of patients with confirmed acute coronary syndrome with ongoing myocardial ischaemia and 89% of patients with confirmed acute coronary syndrome without ongoing myocardial ischaemia (P<0.001). The major adverse cardiac event rate was 9.8% for patients with confirmed acute coronary syndrome with ongoing myocardial ischaemia and 5.5% for patients without ongoing myocardial ischaemia (P=0.005), the 30-day severe bleeding rate was 1.6% and 1.5% (P=1.0). Patients with ongoing myocardial ischaemia admitted to regional hospitals had higher major adverse cardiac event rates compared with patients admitted directly to cardiocentres with percutaneous coronary intervention capability (13.3% vs. 8.2%, P=0.034). CONCLUSIONS: Ongoing myocardial ischaemia was present in more than half of patients hospitalised with acute coronary syndrome. These very high-risk patients may benefit from direct admission to percutaneous coronary intervention-capable centres.

Atrial macroreentry tachycardia in patients without obvious structural heart disease or previous cardiac surgical or catheter intervention: characterization of arrhythmogenic substrates, reentry circuits, and results of catheter ablation.

INTRODUCTION: Atrial macroreentry tachycardia (AMRT) in patients without obvious structural heart disease or previous surgical or catheter intervention has not been characterized in detail. METHODS AND RESULTS: Electroanatomical mapping and ablation of right or left AMRT were performed in 33 patients. Right atrial central conduction obstacle was formed by an electrically silent area (ESA) in 15 (68%) patients and by a line of double potentials (DPs) in seven (32%) patients. Left atrial ESAs were found in all 11 patients with the left AMRT. Reentry circuit was reconstructed in 19 (86%) patients with right AMRT and seven (64%) patients with left AMRT. Of the ESA-related right AMRT, eight (50%) were double-loop reentry circuits utilizing a narrow critical isthmus within the ESA and eight (50%) were single-loop reentry circuits with a critical isthmus bounded by ESA and either ostium of the vena cava. Single-loop DP-related AMRTs had the critical isthmus between the DP line and the ostium of the inferior vena cava (IVC). Left AMRTs included a variety of single-, double-, or triple-loop reentry circuits and their critical isthmuses. During the 37 +/- 15 month follow-up, atrial tachyarrhythmia-free clinical outcome was achieved in 21 (95%) patients (18 patients, 82%, without antiarrhythmic drugs) with the right AMRT and in nine (82%) patients (six patients, 55%, without antiarrhythmic drugs) with the left AMRT. CONCLUSION: The majority of right and left AMRTs were related to the presence of ESA. Ablation can be successful with a favorable risk of atrial tachyarrhythmia recurrence.