Lesion-Specific and Vessel-Related Determinants of Fractional Flow Reserve Beyond Coronary Artery Stenosis

Objectives

The aims of the present study were: 1) to investigate the contribution of the extent of luminal stenosis and other lesion composition-related factors in predicting invasive fractional flow reserve (FFR); and 2) to explore the distribution of various combinations of morphological characteristics and the severity of stenosis among lesions demonstrating normal and abnormal FFR.

Pre-Angioplasty Instantaneous Wave-Free Ratio Pullback Predicts Hemodynamic Outcome In Humans With Coronary Artery Disease: Primary Results of the International Multicenter iFR GRADIENT Registry

Objectives

The authors sought to evaluate the accuracy of instantaneous wave-Free Ratio (iFR) pullback measurements to predict post-percutaneous coronary intervention (PCI) physiological outcomes, and to quantify how often iFR pullback alters PCI strategy in real-world clinical settings.

Pitfalls in comparison of coronary artery measurements of Indian population with different geographical area studies

IntroductionCoronary artery disease (CAD) is the most common cause of morbidity and mortality especially in the developing countries. Coronary artery measurements (CAM) are the most important factor affecting the procedure and outcome of coronary angioplasty (PCI) as well as coronary by-pass operations (CABG). In this study, we aimed to establish a database for the normal CAM as well as for gender difference among the Indian population using quantitative coronary angiography (QCA) with an objective of assessing normal coronary vessel morphology of patients with normal coronaries.Materials and methodsFour thousand angiograms from patients of Indian origin were studied prospectively after procuring the sanction for the same from the ethical committee of the pre-selected hospitals of four states in India. Informed consents were obtained. Post CABG, post PCI patients and patient being diabetic for ≥5 years were also excluded from the study.ResultsTen segments from right and left coronary arteries were taken for diameter measurements. These coronary diameters were indexed to body surface area (BSA) (mean diameter mm/m² BSA). Among, 4000 patients, 933(23.3%) [M:F-521:412] had normal coronaries and 3067 (76.7%) were diseased.Discussion and conclusionThe dimensions of the coronary artery segments of Indians were smaller (in BSA indexed and non-indexed data), compared to studies from other continents which can be due to their smaller BSA.     

The Impact of Downstream Coronary Stenosis on Fractional Flow Reserve Assessment of Intermediate Left Main Coronary Artery Disease: Human Validation

ObjectivesThe aim of this study was to determine the impact of downstream coronary stenosis in the left anterior descending coronary artery (LAD) or left circumflex coronary artery (LCx) on the assessment of fractional flow reserve (FFR) across an intermediate left main coronary artery (LMCA) stenosis in humans with the pressure wire positioned in the nondiseased downstream vessel.BackgroundAccurate assessment of intermediate LMCA disease is critical for guiding decisions regarding revascularization. In theory, FFR across an intermediate LMCA stenosis will be affected by downstream disease, even if the pressure wire is positioned in the nondiseased downstream vessel.MethodsAfter percutaneous coronary intervention of the LAD, LCx, or both, an intermediate LMCA stenosis was created with a deflated balloon catheter. FFR was measured in the LAD and LCx coronary arteries before and after creation of downstream stenosis by inflating an angioplasty balloon within the newly placed stent. The true FFR (FFR_true) of the LMCA, measured in the nondiseased downstream vessel in the absence of stenosis in the other vessel, was compared with the apparent FFR (FFR_app) measured in the presence of stenosis.ResultsIn 25 patients, 91 pairs of measurements were made, 71 with LAD stenosis and 20 with LCx stenosis. FFR_true of the LMCA was significantly lower than FFR_app (0.81 ± 0.08 vs. 0.83 ± 0.08, p < 0.001), although the numerical difference was small. This difference correlated with the severity of the downstream disease (r = 0.35, p < 0.001). In all cases in which FFR_app was >0.85, FFR_true was >0.80.ConclusionsIn most cases, downstream disease does not have a clinically significant impact on the assessment of FFR across an intermediate LMCA stenosis with the pressure wire positioned in the nondiseased vessel.     

Effect of chronic pretreatment with beta-blockers on no-reflow phenomenon in diabetic patients with acute ST-elevation myocardial infarction undergoing primary percutaneous coronary intervention

Background

No-reflow is an important factor as it predicts a poor outcome in patients undergoing primary angioplasty. In comparison with patients attaining TIMI 3 flow, patients with no-reflow have an increased incidence of ventricular arrhythmias, early congestive cardiac failure, cardiac rupture and cardiac death. As such, it is of paramount importance to consider strategies to prevent the occurrence of no-reflow phenomenon. Previous evidence suggests that Beta (β) blockers have multiple favorable effects on the vascular system not directly related to their effect on blood pressure. However, there are insufficient data regarding the effects of prior Beta blocker use on coronary blood flow after primary PCI in patients with AMI.