Impact of Substance Use Disorder on Midterm Mortality After Valve Surgery for Endocarditis.

BACKGROUND: Fueled by the burgeoning opioid epidemic, valve surgeries for substance use disorder-related infective endocarditis (SUD-IE) are increasing. The impact of substance use disorder on postvalve replacement morbidity needs further investigation. METHODS: We queried The Society of Thoracic Surgeons Adult Cardiac Surgery Database for all valve surgeries for infective endocarditis at Tufts Medical Center (2002-2016) and collected demographic and disease-related data, including timing of mortality subclassified as short-term (<6 months including operative), midterm (6 months to 5 years), and extended-term (>5 years). Patients with documentation of illicit drug use before the operation were considered to have SUD-IE. Deaths were confirmed through review of medical record and matching with the Massachusetts Vital Statistics Database. We performed univariate and multivariate proportional hazard regressions examining the impact of substance use disorder mortality in people who received a valve replacement. RESULTS: In the cohort of 228 patients, 80 (35%) had SUD-IE. Eight-six people (38%) died, and overall mortality was higher in people with SUD-IE compared with non-SUD-IE (48% vs 32%, P = .025). SUD-IE was associated with a higher risk of overall mortality (adjusted hazard ratio, 2.41; 95% confidence interval, 1.38-4.20; P = .002). Although the difference between short-term or extended-term mortality was not significant, SUD-IE was associated with increased frequency of midterm mortality (53% vs 31%, P = .003). CONCLUSIONS: Our data reflect high rates of postvalve surgery morbidity and mortality in people with SUD-IE at a tertiary care center. The midterm postoperative period is a vulnerable period for people with SUD-IE worthy of further investigation.

Racial differences in central hemodynamic burden in men with HIV: preliminary findings.

OBJECTIVES: African Americans infected with HIV are almost 3 times more likely to die from cardiovascular disease (CVD) than their White HIV-infected counterparts. The purpose of this study was to examine racial differences in novel measures of vascular function and CVD risk in African American and White men infected with HIV. DESIGN: Our study uses a cross-sectional approach. SETTING: Participants were recruited from the nutrition/infectious disease clinic at a large metropolitan hospital. PARTICIPANTS: African American men (n=21) and White men (n=21) with HIV on stable anti-retroviral therapy were included in this study. MAIN OUTCOME MEASURES: High resolution ultrasound was used to assess brachial artery flow mediated dilation (FMD). Applanation tonometry was used to measure carotid-femoral and carotid-radial pulse wave velocity (PWV), carotid augmentation index (Alx) and carotid-brachial pulse pressure (PP) amplification. Left ventricular (LV) pressure effort was derived from the contour of the central BP waveform. RESULTS: There were no racial differences in brachial FMD (African American: 4.9 +/- 1.1 vs White: 5.4 +/- 1.0%; P>.05) or carotid-femoral PWV (African American: 8.9 +/- .6 vs White: 8.7 +/- .4 m/s; P>.05). African American men with HIV had significantly higher carotid-radial PWV (11.3 +/- .4 vs 9.8 +/- .3 m/s; P<.05), higher carotid Alx (6 +/- 3 vs -1 +/- 2%; P<.05), higher LV pressure effort (2262 +/- 369 vs 1030 +/- 140 dyne sec/cm2; P<.05) and lower PP amplification (1.10 +/- .03 vs 1.24 +/- .03; P<.05) compared to White men with HIV. CONCLUSION: Elevated CVD risk in African American men with HIV may be partially mediated by increased central hemodynamic burden and not endothelial dysfunction or increased aortic stiffness.

Augmentation index and aortic stiffness in bicuspid aortic valve patients with non-dilated proximal aortas.

BACKGROUND: We compared aortic stiffness, aortic impedance and pressure from wave reflections in the setting of bicuspid aortic valve (BAV) to the tricuspid aortic valve (TAV) in the absence of proximal aortic dilation. We hypothesized BAV is associated with abnormal arterial stiffness. METHODS: Ten BAV subjects (47 ± 4 years, 6 male) and 13 TAV subjects (46 ± 4 years, 10 male) without significant aortic valve disease were prospectively recruited. Characteristic impedance (Zc) was derived from echocardiographic images and pulse wave Doppler of the left ventricular outflow tract. Applanation tonometry was performed to obtain pulse wave velocity (PWV) at several sites as measures of arterial stiffness and augmentation index (AIx) as a measure of wave reflection. RESULTS: There were no significant differences between BAV and TAV subjects with regard to heart rate or blood pressure. Zc was similar between BAV and TAV subjects (p=0.25) as was carotid-femoral pulse wave velocity (cf-PWV) and carotid-radial PWV (cr-PWV) between BAV and TAV subjects (p=0.99). Carotid AIx was significantly higher in BAV patients compared with TAV patients (14.3 ± 4.18% versus -3.02 ± 3.96%, p=0.007). CONCLUSIONS: Aortic stiffness and impedance is similar between subjects with BAV and TAV with normal aortic dimensions. The significantly higher carotid AIx in BAV, a proxy of increased pressure from wave reflections, may reflect abnormal vascular function distal to the aorta.

Systemic vascular function is associated with muscular power in older adults.

Age-associated loss of muscular strength and muscular power is a critical determinant of loss of physical function and progression to disability in older adults. In this study, we examined the association of systemic vascular function and measures of muscle strength and power in older adults. Measures of vascular endothelial function included brachial artery flow-mediated dilation (FMD) and the pulse wave amplitude reactive hyperemia index (PWA-RHI). Augmentation index (AIx) was taken as a measure of systemic vascular function related to arterial stiffness and wave reflection. Measures of muscular strength included one repetition maximum (1RM) for a bilateral leg press. Peak muscular power was measured during 5 repetitions performed as fast as possible for bilateral leg press at 40% 1RM. Muscular power was associated with brachial FMD (r = 0.43, P < 0.05), PWA-RHI (r = 0.42, P < 0.05), and AIx (r = -0.54, P < 0.05). Muscular strength was not associated with any measure of vascular function. In conclusion, systemic vascular function is associated with lower-limb muscular power but not muscular strength in older adults. Whether loss of muscular power with aging contributes to systemic vascular deconditioning or vascular dysfunction contributes to decrements in muscular power remains to be determined.

Whole blood leukocytes isolation with microfabricated filter for cell analysis.

The flow cytometric analysis of leukocytes in whole blood usually requires isolation of leukocytes from other components of whole blood. Density gradient centrifugation and red blood cell lysis are the most commonly used methods to separate leukocytes but come with significant limitations. We report the results of the evaluation of a microfabricated filtration device for blood preparation that separates erythrocytes from leukocytes based on their size and mechanical properties. The microfabricated filter evaluated here requires a rapid and simple procedure and results in high leukocytes recovery without introducing bias among the leukocyte subpopulations. The filter removes erythrocytes, platelets, plasma proteins, and unbound staining reagent. This gentle filtration process produces very clean stained leukocytes for cytometric analysis without any apparent damage to leukocytes.

Augmentation index derived from peripheral arterial tonometry correlates with cardiovascular risk factors.

Background. Augmentation index (AIx) is traditionally obtained from pressure waveforms via arterial applanation tonometry. We sought to evaluate the association between AIx obtained from peripheral arterial tonometry (PAT) with cardiovascular risk factors (CRF) and coronary artery disease (CAD). Methods. 186 patients were enrolled in the study. The presence or absence of CRFs and CAD was assessed in each subject. AIx was calculated by an automated algorithm averaging pulse wave amplitude data obtained via PAT. Central blood pressures were assessed in a subset of patients undergoing clinically indicated cardiac catheterization. Results. An association was observed between AIx and age, heart rate, systolic blood pressure, mean arterial pressure, pulse pressure, body weight and body mass index. AIx was significantly lower in patients with <3 CRFs compared to those with >5 CRFs ( P = .02). CAD+ patients had significantly higher AIx compared to CAD- patients ( P = .008). Area under the ROC curve was 0.604 (P < .01). In patients undergoing cardiac catheterization, after adjusting for age, height and heart rate, AIx was a significant predictor of aortic systolic and pulse pressures (P < .05) Conclusion. AIx derived from PAT correlates with cardiac risk factors and CAD. It may be a useful measure of assessing overall risk for coronary artery disease.