Percutaneous coronary intervention of functionally nonsignificant stenosis: 5-year follow-up of the DEFER Study.

OBJECTIVES: The purpose of this study was to investigate the appropriateness of stenting a functionally nonsignificant stenosis. BACKGROUND: Percutaneous coronary intervention (PCI) of an intermediate stenosis without evidence of ischemia is often performed, but its benefit is unproven. Coronary pressure-derived fractional flow reserve (FFR) is an invasive index used to identify a stenosis responsible for reversible ischemia. METHODS: In 325 patients scheduled for PCI of an intermediate stenosis, FFR was measured just before the planned intervention. If FFR was >or =0.75, patients were randomly assigned to deferral (Defer group; n = 91) or performance (Perform group; n = 90) of PCI. If FFR was <0.75, PCI was performed as planned (Reference group; n = 144). Clinical follow-up was 5 years. RESULTS: There were no differences in baseline clinical characteristics between the 3 groups. Complete follow-up was obtained in 98% of the patients. Event-free survival was not different between the Defer and Perform groups (80% and 73%, respectively; p = 0.52), but was significantly worse in the Reference group (63%; p = 0.03). The composite rate of cardiac death and acute myocardial infarction in the Defer, Perform, and Reference groups was 3.3%, 7.9%, and 15.7%, respectively (p = 0.21 for Defer vs. Perform group; p = 0.003 for the Reference vs. both other groups). The percentage of patients free from chest pain at follow-up was not different between the Defer and Perform groups. CONCLUSIONS: Five-year outcome after deferral of PCI of an intermediate coronary stenosis based on FFR >/=0.75 is excellent. The risk of cardiac death or myocardial infarction related to this stenosis is <1% per year and not decreased by stenting.

Angiographic, intravascular ultrasound, and fractional flow reserve evaluation of direct stenting vs. conventional stenting using BeStent2 in a multicentre randomized trial.

AIMS: Direct stenting (DS) may not be as safe and effective as conventional stenting. The objective was to demonstrate equivalence of post-procedural mean luminal diameter (MLD) by angiography after BeStent2 placement between DS and pre-dilatation (PD) strategy. METHODS AND RESULTS: Two hundred and two patients with a single de novo lesion (diameter >/=3.0 mm and length

Percutaneous coronary intervention or bypass surgery in multivessel disease? A tailored approach based on coronary pressure measurement.

The optimal revascularization strategy, percutaneous coronary intervention (PCI) or coronary artery bypass graft surgery (CABG), for patients with multivessel coronary artery disease (MVD) remains controversial. The aim of the present study was to compare the long-term outcomes after selective PCI of only hemodynamically significant lesions (fractional flow reserve, or FFR < 0.75) to CABG of all stenoses in patients with MVD. In 150 patients with MVD referred for CABG, FFR was determined in 381 coronary arteries considered for bypass grafting. If the FFR was less than 0.75 in three vessels or in two vessels including the proximal left anterior descending (LAD) artery, CABG was performed (CABG group). If only one or two vessels were physiologically significant (not including the proximal LAD), PCI of those lesions was performed (PCI group). Of the 150 patients, 87 fulfilled the criteria for CABG and 63 for PCI. There were no significant differences in the angiographic or other baseline characteristics between the two groups. At 2-year follow-up, no differences were seen in adverse events, including repeat revascularization (event-free survival 74% in the CABG group and 72% in the PCI group). A similar number of patients were free from angina (84% in the CABG group and 82% in the PCI group). Importantly, the results in both groups were as good as the surgical groups in previous studies comparing PCI and CABG in MVD. In patients with multivessel disease, PCI in those with one or two hemodynamically significant lesions as identified by an FFR < 0.75 yields a similar favorable outcome as CABG in those with three or more culprit lesions despite a similar angiographic extent of disease.

Intracoronary and intravenous adenosine 5'-triphosphate, adenosine, papaverine, and contrast medium to assess fractional flow reserve in humans.

BACKGROUND: Inducing both maximal and steady-state coronary hyperemia is of clinical importance to take full advantage of fractional flow reserve measurements. The present study compares different dosages and routes of administration of adenosine 5'-triphosphate (ATP), adenosine, contrast medium, and papaverine regarding their potential to achieve both maximal and steady-state hyperemia. METHODS AND RESULTS: In 21 patients with an isolated coronary stenosis, coronary vasodilation was induced successively by papaverine (20 mg intracoronary), adenosine (20 and 40 microg intracoronary), ATP (20 and 40 microg intracoronary), iohexol (6 mL intracoronary), adenosine or ATP through an antecubital vein (140 and 180 microg x kg(-1) x min(-1)), or adenosine or ATP through a femoral vein (140 and 180 microg x kg(-1) x min(-1)). Because vessel dimensions did not change, the ratio of distal coronary pressure (Pd) to aortic pressure (Pa) was used as an index of myocardial resistance. Pd/Pa was 0.77+/-0.21 at rest and decreased to 0.61+/-0.21 after papaverine. Pd/Pa decreased to a similar level with all other vasodilators, except with contrast medium (0.68+/-0.21; P<0.01 versus papaverine). Steady-state hyperemia could only be obtained by intracoronary papaverine and by intravenous ATP or adenosine. In another 23 patients, an intravenous infusion of ATP was varied from 0 to 280 microg x kg(-1) x min(-1). At doses >140 microg x kg(-1) x min(-1), there was neither a further decrease in Pd/Pa ratio nor a further increase in coronary flow velocities. CONCLUSIONS: Provided sufficient dosages are used, ATP, adenosine, and papaverine (but not contrast medium) induce maximal hyperemia and are therefore suitable to assess fractional flow reserve. Only intracoronary papaverine and intravenous ATP or adenosine induce steady-state hyperemia enabling a pressure pullback maneuver that is useful in assessing diffuse coronary atherosclerosis.