No abstract

Background-Discordance between fractional flow reserve (FFR) and coronary flow velocity reserve (CFVR) may reflect important coronary pathophysiology but usually remains unnoticed in clinical practice. We evaluated the physiological basis and clinical outcome associated with FFR/CFVR discordance. Methods and Results-We studied 157 intermediate coronary stenoses in 157 patients, evaluated by FFR and CFVR between April 1997 and September 2006 in which revascularization was deferred. Long-term follow-up was performed to document the occurrence of major adverse cardiac events: cardiac death, myocardial infarction, or target vessel revascularization. Discordance between FFR and CFVR occurred in 31% and 37% of stenoses at the 0.75, and 0.80 FFR cut-off value, respectively, and was characterized by microvascular resistances during basal and hyperemic conditions. Follow-up duration amounted to 11.7 years (Q1-Q3, 9.9-13.3 years). Compared with concordant normal results of FFR and CFVR, a normal FFR with an abnormal CFVR was associated with significantly increased major adverse cardiac events rate throughout 10 years of follow-up, regardless of the FFR cut-off applied. In contrast, an abnormal FFR with a normal CFVR was associated with equivalent clinical outcome compared with concordant normal results: ≤3 years when FFR <0.75 was depicted abnormal and throughout 10 years of follow-up when FFR ≤0.80 was depicted abnormal. Conclusions-Discordance of CFVR with FFR originates from the involvement of the coronary microvasculature. Importantly, the risk for major adverse cardiac events associated with FFR/CFVR discordance is mainly attributable to stenoses where CFVR is abnormal. This emphasizes the requirement of intracoronary flow assessment in addition to coronary pressure for optimal risk stratification in stable coronary artery disease. (Circ Cardiovasc Interv. 2014;7:301-311.)Key Words: coronary flow velocity reserve ◼ coronary microcirculation ◼ fractional flow reserve ◼ stable coronary artery disease

The aim of this study was to evaluate the value of microvascular obstruction (MO) and infarct size as a percentage of left ventricular mass (IS%LV), as measured by contrast-enhanced cardiac magnetic resonance, in predicting major cardiovascular adverse events (MACE) at 2 years in patients with ST-segment elevation myocardial infarction reperfused by primary percutaneous coronary intervention. Individual data from 1,025 patients were entered into the pooled analysis. MO was associated with the occurrence of MACE, defined as a composite of cardiac death, congestive heart failure, and myocardial re-infarction (adjusted hazard ratio: 3.74; 95% confidence interval: 2.21 to 6.34). IS%LV ≥25% was not associated with MACE (adjusted hazard ratio: 0.90; 95% confidence interval: 0.59 to 1.37). The authors conclude that MO is an independent predictor of MACE and cardiac death, whereas IS%LV is not independently associated with MACE.

Overall, this study showed a unique spatiotemporal pattern of monocyte accumulation in the human myocardium following AMI that coincides with a marked depletion of monocytes from the spleen, suggesting that the human spleen contains an important reservoir function for monocytes.