Usefulness of fractional flow reserve to improve diagnostic efficiency in patients with non-ST elevation myocardial infarction.

Myocardial fractional flow reserve (FFR) has emerging clinical utility and prognostic value in medically stabilized patients with non-ST-segment elevation myocardial infarction (NSTEMI). The aim of this study was to investigate whether measurement of FFR compared to coronary angiography alone improves diagnostic efficiency in patients with NSTEMIs. One hundred consecutive patients with NSTEMIs who had previously undergone clinically indicated FFR measurements were included. In a simulated decision exercise, 5 interventional cardiologists retrospectively and independently reviewed the clinical history and coronary angiogram of each patient and then made a treatment decision. FFR results were then disclosed, and the same cardiologists were asked to review their initial treatment decisions. A p value <0.05 indicates a difference between cardiologists. The proportion of patients allocated to each treatment option initially differed among the 5 cardiologists (p = 0.0061). Forty-two percent of all FFR measurements were made in culprit lesions. After FFR disclosure, the number of patients in whom the treatment decisions made by each cardiologist independently conformed (and so represented the majority with ≥ 3 of the 5 cardiologists) increased from 65% to 91% (p = 0.0094). After FFR disclosure, the cardiologists changed their initial treatment plans in 46% of patients (p = 0.0016). Changes in favor of medical therapy occurred in 24% of patients (p = 0.0016), and this increase was associated with reductions in "deferred" management (p = 0.0067), single-vessel percutaneous coronary intervention (p = 0.0052), and multivessel percutaneous coronary intervention (p = 0.046). In conclusion, FFR measurement reduced diagnostic variability and changed cardiologists' treatment decisions for patients with NSTEMIs.

Effects of sumatriptan and eletriptan on diseased epicardial coronary arteries.

BACKGROUND: Triptans are contraindicated in patients with known or suspected coronary artery disease (CAD); however, few studies have evaluated triptans in patients with obstructive CAD to quantify the vasoconstrictive effect on diseased coronary vessels. METHODS: Patients undergoing percutaneous transluminal coronary angioplasty for symptomatic single-vessel CAD were randomised to one of three parallel cohorts to receive (1) 6 mg intravenously (IV) infused eletriptan plus subcutaneous (SC) placebo, (2) IV infused placebo plus 6 mg SC sumatriptan or (3) IV infused placebo plus SC placebo, as simultaneous administrations in a double-blind manner. Serial arteriograms, hemodynamic indices, electrocardiography and triptan plasma concentrations were obtained. RESULTS: . Fifteen minutes after triptan challenge, median (95% confidence interval) changes in coronary artery diameter (CADM) at the focal point of the stenosed segment were: dilation of 2.6% (-5.0, 11.4), eletriptan 6 mg IV (n = 18); constriction of 6.8% (-12.6, 0.4), sumatriptan 6 mg SC (n = 17), and constriction of 4.5% (-7.0, 7.9), placebo (n = 10). One patient had angiographic evidence of a new thrombus at the stenosis site, necessitating termination of study infusion and successful stenting of the lesion. There was no correlation between effects on CADM and triptan concentration, or between hemodynamic or electrocardiograph changes and the presence (n = 13) or absence (n = 33) of chest pain. CONCLUSIONS: Triptans had very little effect on diseased epicardial coronary arteries in a small group of angina sufferers with established CAD. Results should be interpreted cautiously since there may be instances where even modest triptan-associated epicardial constriction is sufficient to precipitate myocardial ischemia in patients with severe obstructive CAD.