Vascular function in continuous-flow left ventricular assist device recipients: effect of a single pulsatility treatment session.

Vascular function is further attenuated in patients with chronic heart failure implanted with a continuous-flow left ventricular assist device (LVAD), likely due to decreased arterial pulsatility, and this may contribute to LVAD-associated cardiovascular complications. However, the impact of increasing pulsatility on vascular function in this population is unknown. Therefore, 15 LVAD recipients and 15 well-matched controls underwent a 45-min, unilateral, arm pulsatility treatment, evoked by intermittent cuff inflation/deflation (2-s duty cycle), distal to the elbow.

Nitric oxide synthase inhibition with N(G)-monomethyl-l-arginine: Determining the window of effect in the human vasculature.

Nitric oxide synthase (NOS) inhibition with N(G)-monomethyl-l-arginine (L-NMMA) is often used to assess the role of NO in human cardiovascular function. However, the window of effect for L-NMMA on human vascular function is unknown, which is critical for designing and interpreting human-based studies. This study utilized the passive leg movement (PLM) assessment of vascular function, which is predominantly NO-mediated, in 7 young male subjects under control conditions, immediately following intra-arterial L-NMMA infusion (0.

Targeting Peripheral Vascular Pulsatility in Heart Failure Patients with Continuous-Flow Left Ventricular Assist Devices: The Impact of Pump Speed.

Current continuous-flow left ventricular assist devices (LVADs) decrease peripheral vascular pulsatility, which may contribute to side effects such as bleeding and thrombotic events. However, the actual impact of manipulating LVAD pump speed, revolutions per minute (rpm), on peripheral (brachial) pulsatility index (brachial PI), in patients with heart failure implanted with a HeartWare (HVAD) or HeartMateII (HMII) LVAD is unknown. Therefore, blood velocities (Doppler ultrasound) in the brachial artery were recorded and brachial PI calculated across rpm manipulations which spanned the acceptable clinical outpatient range: 360 rpm (HVAD, n = 10) and 1200 rpm (HMII, n = 10).

Delineating the age-related attenuation of vascular function: Evidence supporting the efficacy of the single passive leg movement as a screening tool.

Continuous passive leg movement (PLM) is a promising clinical assessment of the age-related decline in peripheral vascular function. To further refine PLM, this study evaluated the efficacy of a single PLM (sPLM), a simplified variant of the more established continuous movement approach, to delineate between healthy young and old men based on vascular function. Twelve young (26 ± 5 yr) and 12 old (70 ± 7 yr) subjects underwent sPLM (a single passive flexion and extension of the knee joint through 90°), with leg blood flow (LBF, common femoral artery with Doppler ultrasound), blood pressure (finger photoplethysmography), and leg vascular conductance (LVC) assessed.

Single passive leg movement assessment of vascular function: contribution of nitric oxide.

Broxterman RM, Trinity JD, Gifford JR, Kwon OS, Kithas AC, Hydren JR, Nelson AD, Morgan DE, Jessop JE, Bledsoe AD, Richardson RS. Single passive leg movement assessment of vascular function: contribution of nitric oxide. J Appl Physiol 123: 1468-1476, 2017.