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The aims of this work were (1) to compare cerebral oxygenation-perfusion (COP), central hemodynamics, and peak oxygen uptake (V˙o2peak) in heart transplant recipients (HTRs) vs age-matched healthy controls (AMHCs) during exercise and recovery and (2) to study the relationships between COP, central hemodynamics, and V˙o2peak in HTRs and AMHCs.Twenty-six HTRs (3 women) and 27 AMHCs (5 women) were recruited. Maximal cardiopulmonary function (gas exchange analysis), cardiac hemodynamics (impedance cardiography), and left frontal COP (near-infrared spectroscopy) were measured continuously during and after a maximal ergocycle (Ergoline 800S, Bitz, Germany) test.Compared with AMHCs, HTRs had lower V˙o2peak, maximal cardiac index (CImax), and maximal ventilatory variables (P0.05). COP was lower during exercise (oxyhemoglobin [ΔO2Hb], 50% and 75% of V˙O2peak, total hemoglobin [ΔtHb], 100% of V˙O2peak; P0.05), and recovery in HTRs (ΔO2Hb, minutes 2-5; ΔtHb, minutes 1-5; P0.05) compared with AMHCs. End-tidal pressure of CO2 was lower during exercise compared with that in AMHCs (P0.0001). In HTRs, CImax was positively correlated with exercise cerebral hemodynamics (R = 0.54-0.60; P0.01).In HTRs, COP was reduced during exercise and recovery compared with that in AMHCs, potentially because of a combination of blunted cerebral vasodilation by CO2, cerebrovascular dysfunction, reduced cardiac function, and medication. The impaired V˙O2peak observed in HTRs was mainly caused by reduced maximal ventilation and CI. In HTRs, COP is impaired and is correlated with cardiac function, potentially impacting cognitive function. Therefore, we need to study which interventions (eg, exercise training) are most effective for improving or normalizing (or both) COP during and after exercise in HTRs.

BACKGROUND: Accurate measurement of physical activity (PA) is necessary to monitor trends, assess relations with health and measure adherence to PA guidelines. While accelerometers provide accurate measures of PA they rely on validated cut-points to quantify time spent in light, moderate and vigorous intensities. Cut-points have largely been established using healthy populations; however, accelerometer output can differ based on cardiorespiratory fitness, suggesting that among individuals with compromised functioning such as those with coronary artery disease (CAD); these cut-points may lead to a misclassification of intensity. The objective of this study was to compare well-known and widely used cut-points (Sasaki) derived from healthy adults with those developed in a CAD population (Mark). METHODS: Two-hundred and thirty-one adults with CAD (mean SD: 63.7 9.2 years) wore an ActiGraph GT3X accelerometer for a minimum of 4 consecutive days and 10 hours/day. Daily time spent in moderate-to-vigorous PA (MVPA) was compared using two cut-point definitions: Mark (58.3 10.7 years, mean v

s S161 METHODS: At 79 centers in 19 countries, 4752 patients scheduled for CABG were randomly assigned to undergo the procedure off-pump or on-pump in the CABG Off or On Pump Revascularization (CORONARY) study. The primary study outcome was a composite of death, stroke, myocardial infarction, or new renal failure requiring dialysis. Outcomes were adjudicated by a central committee. We compared the risk factors and outcomes by transfusion status. RESULTS: Blood transfusions were more often required for patients randomly assigned to on-pump CABG with 1415/ 2362 (60%) versus 1088/2356 (46%) receiving at least one unit of red blood cells (p 1 unit of blood (p 1 unit of blood varied by center from 0% to 100%. After taking into account institutional variations in transfusion pattern, independent risk factors for receiving > 1 unit of blood included female gender, smaller body surface area, ADP receptor blocker use, chronic kidney disease, higher EuroSCORE, triple-vessel disease, onpump CABG, need for an intraaortic balloon pump, greater postoperative blood loss and any postoperative reoperation (all p 1 unit of blood presented an increased risk for the composite outcome at 1 year (hazard ratio: 0.67 [0.54-0.84]; p

(CO) and cerebral oxygenation/perfusion (COP) in heart transplant recipients (HTR) and age-matched controls (AMC) during maximal exercise (ME), 2) to study the relationships between VO2 peak, CO, COP inHTR and AMC. 27 AMC and 26HTR were recruited. VO2 peak and cardiac hemodynamic (impedance cardiography) were measured during a ME. COP (O2Hb, tHb) was measured using near-infrared spectroscopy (NIRS). RESULTS: Compared to AMC, HTR had a lower VO2 peak (ml/min/kg of lean body mass), maximal (max) cardiac index (CImax), max ventilation, max tidal volume and max respiratory frequency vs. AMC (P