The Age-Dependent Contribution of Aortic Incident and Reflected Pressure Waves to Central Blood Pressure in African-Americans

Aging is associated with increased central aortic systolic pressure (CSP) and pulse pressure which are predictive of cardiovascular events. Mechanisms implicated for higher central pressures include a higher forward incident pressure wave (P1), higher augmented pressure (AP), and shorter reflected wave round trip travel time (Tr). African-Americans (AA) have more frequent and deleterious blood pressure elevation. Using applanation tonometry, we studied the association of age and CSP with P1 and AP in 900 AA subjects. Data showed that in subjects ≤50 years old, CSP was mediated by AP but not P1 or Tr, whereas in those >50, CSP was mediated by both AP and P1 and to a lesser extent by Tr. Predictive models were significant (R2 = 0.97) for both age groups. In conclusion, wave reflection is the primary determinant of CSP in younger AA, while in older subjects, CSP is mediated by both the magnitude and timing of wave reflection as well as aortic impedance

Characterization of Arterial Wave Reflection in Healthy Bonnet Macaques: Feasibility of Applanation Tonometry

Nonhuman primates are commonly used in cardiovascular research. Increased arterial stiffness is a marker of subclinical atherosclerosis and higher CV risk. We determined the augmentation index (AI) using applanation tonometry in 61 healthy monkeys (59% female, age 1–25 years). Technically adequate studies were obtained in all subjects and required 1.5 ± 1.3 minutes. The brachial artery provided the highest yield (95%). AI was correlated with heart rate (HR) (r = −0.65, P < .001), crown rump length (CRL) (r = 0.42, P = .001), and left ventricular (LV) mass determined using echocardiography (r = 0.52, P < .001). On multivariate analysis, HR (P < .001) and CRL (P = .005) were independent predictors of AI (R2 = 0.46, P < .001). Body Mass Index (BMI) and AI were independent predictors of higher LV mass on multivariate analysis (P < .001 and P = .03). In conclusion, applanation tonometry is feasible for determining AI. Reference values are provided for AI in bonnet macaques, in whom higher AI is related to HR and CRL, and in turn contributes to higher LV mass

First Reported Case of Hemopericardium Related to Dabigatran Use Reversed by New Antidote Idarucizumab

Dabigatran, the first novel oral anticoagulant (NOAC) with a reversal agent, heralded a paradigm shift in the treatment of nonvalvular atrial fibrillation. The potential for life-threatening hemorrhagic events with the use of NOACs has been highly debated since the effectiveness of reversal agents such as idarucizumab is based primarily on pharmacologic data. It is known that cancer patients are at an increased risk of bleeding with anticoagulation, though specific studies demonstrating the risks or efficacy of NOACs in this population are lacking. We provide the first report of hemopericardium resulting in multiorgan failure related to dabigatran use that was successfully reversed by idarucizumab in a man with prostate cancer on chemotherapy

QPV interval as a measure of arterial stiffness in women with systemic lupus erythematosus.

BACKGROUND: Systemic lupus erythematosus (SLE) is associated with premature atherosclerosis and increased arterial stiffness. The QPV interval has been proposed as a measure of arterial stiffness. The QPV interval is based on the premise that transit time from cardiac ejection to brachial artery flow is shortened in patients with increased arterial stiffness. HYPOTHESIS: The objective of this study was to determine the significance of the QPV interval as a measure of arterial stiffness in patients with SLE. METHODS: We prospectively studied 46 female SLE patients. The QPV interval was calculated as the time from onset of the QRS complex to peak flow velocity of the brachial artery during ultrasound examination. Measurements of arterial stiffness: augmentation index (AI) and pulse wave velocity (PWV) were obtained by applanation tonometry while patients were on a stable medical regimen. RESULTS: Mean age was 44+/-14 y and mean QPV interval was 198+/-18 msec QPV interval correlated inversely with age (r=-0.39, p=0.008), AI (r=-0.41, p=0.004), PWV (r=-0.39, p=0.007), and aortic pulse pressure (PP) (r=-0.45, p=0.002). On multivariate regression analysis, QPV interval was found to be an independent predictor of PWV after adjusting for age (R2=0.26, p\u3c0.001). CONCLUSION: In women with SLE, QPV decreases with age and is inversely related with measures of arterial stiffness. QPV may be useful in identifying SLE patients with higher arterial stiffness in the clinical or research setting. Further larger studies are needed to confirm these preliminary results

Arterial Wave Reflection in HIV-Infected and HIV-Uninfected Rwandan Women

To assess differences in arterial wave reflection, a marker of atherosclerosis, in HIV-positive and HIV-negative Rwandan women, applanation tonometry was performed on 276 HIV+ and 67 HIV− participants. Radial artery pressure waveforms were recorded and central aortic waveforms were derived by validated transfer function. Central augmentation index (C-AI), central pulse pressure (C-PP), and peripheral augmentation index (P-AI) were measured. HIV+ participants were younger and had lower diastolic blood pressure (BP) and 41% of the HIV+ women were taking antiretroviral therapy (ART). Mean C-AI and P-AI were significantly lower in HIV-infected than in uninfected participants (20.3 ± 12.0 vs. 25.5 ± 12.1, p = 0.002 and 74.6 ± 18.8 vs. 83.7 ± 20.0, p < 0.001). After age matching, C-AI, C-PP, and P-AI were similar among the groups. On multivariate analysis, age, heart rate, weight, and mean arterial pressure were independently associated with C-AI (R2 = 0.33, p < 0.0001). Among HIV-infected women, current CD4 count did not correlate with C-AI (Rho = −0.01, p = 0.84), C-PP (Rho = 0.09, p = 0.16), or P-AI (Rho = −0.01, p = 0.83). In conclusion, HIV infection was not associated with increased arterial wave reflection in women with little exposure to antiretroviral therapy and without CV risk factors. Whether long-term ART increases measures of arterial stiffness remains unknown

The Effect of Lower Body Positive Pressure on Left Ventricular Ejection Duration in Patients With Heart Failure

Lower body positive pressure (LBPP) treadmill activity might benefit patients with heart failure (HF). To determine the short-term effects of LBPP on left ventricular (LV) function in HF patients, LV ejection duration (ED), a measure of systolic function was prospectively assessed in 30 men with stable HF with LV ejection fraction ≤ 40% and 50 healthy men (N). Baseline measurements (100% body weight), including blood pressure (BP), heart rate (HR) and LVED, obtained via radial artery applanation tonometry, were recorded after 2 minutes of standing on weight support treadmill and after LBPP achieving reductions of 25%, 50%, and 75% of body weight in random sequence. Baseline, HR, and LVED (251 ± 5 vs 264 ± 4 ms; P = .035) were lower in the HF group. The LBPP lowered HR more (14% vs 6%, P = .009) and increased LVED more (15% ± 7% vs 10% ± 6%; P = .004) in N versus HF. Neither group had changes (Δ) in BP. On generalized linear regression, the 2 groups showed different responses ( P < .001). Multivariate analysis showed %ΔHR ( P < .001) and HF ( P = .026) were predictive of ΔED ( r 2 = 0.44; P < .001). In conclusion, progressive LBPP increases LVED in a step-wise manner in N and HF patients independent of HR lowering. The ΔLVED is less marked in patients with HF

The Effect of Lower Body Positive Pressure on Left Ventricular Ejection Duration in Patients With Heart Failure

Lower body positive pressure (LBPP) treadmill activity might benefit patients with heart failure (HF). To determine the short-term effects of LBPP on left ventricular (LV) function in HF patients, LV ejection duration (ED), a measure of systolic function was prospectively assessed in 30 men with stable HF with LV ejection fraction ≤ 40% and 50 healthy men (N). Baseline measurements (100% body weight), including blood pressure (BP), heart rate (HR) and LVED, obtained via radial artery applanation tonometry, were recorded after 2 minutes of standing on weight support treadmill and after LBPP achieving reductions of 25%, 50%, and 75% of body weight in random sequence. Baseline, HR, and LVED (251 ± 5 vs 264 ± 4 ms; P = .035) were lower in the HF group. The LBPP lowered HR more (14% vs 6%, P = .009) and increased LVED more (15% ± 7% vs 10% ± 6%; P = .004) in N versus HF. Neither group had changes (Δ) in BP. On generalized linear regression, the 2 groups showed different responses ( P < .001). Multivariate analysis showed %ΔHR ( P < .001) and HF ( P = .026) were predictive of ΔED ( r 2 = 0.44; P < .001). In conclusion, progressive LBPP increases LVED in a step-wise manner in N and HF patients independent of HR lowering. The ΔLVED is less marked in patients with HF