Barry Kuban - Academia.edu (original) (raw)

Papers by Barry Kuban

Perfusion, 1995

The incidence of death from noncardiac complica-tions following cardiac surgery is increasing whi... more The incidence of death from noncardiac complica-tions following cardiac surgery is increasing while death from cardiac complications has plateaued.l 1 Atherosclerotic emboli from the ascending aorta have been linked to stroke, multiorgan failure and death.2 The force of the high ...

Annals of Biomedical Engineering, 1994

This paper presents a method for measuring arterial geometry in vivo using MRI. The approach was ... more This paper presents a method for measuring arterial geometry in vivo using MRI. The approach was validated using MR images of three perfused compliant casts of human aortic bifurcations whose geometry was known. Preliminary human studies demonstrated the reproducibility of the technique. The approach was applied to 20 normal individuals to study the effects of age, race, and gender on the geometry of the aortic bifurcation. The results show that older people tend to have a smaller bifurcation angle, lower planarity, and larger angular asymmetry than younger people. Asians have larger bifurcation angles than whites. The bifurcation of males is more asymmetric than that of females. These results may have implications regarding the heritability of arterial geometry, the similarities of cardiovascular risk within families, and differences in risk among groups.

Eurointervention Journal of Europcr in Collaboration With the Working Group on Interventional Cardiology of the European Society of Cardiology, Jun 1, 2007

Atherosclerosis is considered both a systemic and focal disease. Current diagnostic tools do not ... more Atherosclerosis is considered both a systemic and focal disease. Current diagnostic tools do not allow adequate in vivo identification and characterisation of lesions. Advanced spectral analysis of IVUS backscatter has displayed the potential for real-time plaque characterisation. The aim of this study is to determine the ex vivo accuracy of automated plaque characterisation by spectral analysis of intravascular ultrasound (IVUS) backscatter. Plaques (n=184) from 51 coronary arteries were imaged by IVUS. The arteries were then pressure fixed and matching histology collected. Regions were selected from histology and corresponding IVUS data were used to build the plaque classification system using spectral analysis and classi-fication trees. Tissue-maps were validated ex vivo by comparison with histology via 899 selected regions (n=94 plaques) that comprised 471 fibrous tissue (FT), 130 fibro-fatty (FF), 132 necrotic-core (NC) and 156 dense-calcium (DC) regions. The overall predictive accuracies were 93.5% for FT, 94.1% for FF, 95.8% for NC, and 96.7% for DC with sensitivities and specificities ranging from 72% to 99%. The Kappa statistic was calculated to be 0.845 indicating very high agreement with histology. Automated spectral analysis of IVUS backscatter provides accurate ex vivo information on plaque composition, with considerable potential for assessment of plaque vulnerability in real-time.

International Journal of Cardiac Imaging, 2000

Several techniques have been used to demonstrate that human arteries respond to atherosclerosis b... more Several techniques have been used to demonstrate that human arteries respond to atherosclerosis by increasing their total arterial area to prevent a decrease in blood¯ow. Three-dimensional reconstructions of coronary arteries can document this compensatory response accurately and speci®cally. Seven human coronary arteries were reconstructed using intravascular ultrasound and biplane angiography, and vessel geometries were quanti®ed. In all seven vessels, as plaque area increased, overall vessel area increased (R 0X986, 0.933, 0.984, 0.678, 0.763, 0.963, and 0.830), but luminal cross-sectional area did not signi®cantly decrease. Focal compensatory enlargement was identi®ed in each vessel, and in some cases this response appeared to occur until the vessel was 65% occluded. Luminal enlargement near the proximal ends was attributed to the natural taper of the vessel. The semi-automated, three-dimensional segmentation technique used in this study allows reproducible quanti®cation, as there is no subjective manual tracing involved. Following the intravascular ultrasound transducer in time and space with biplane angiography allows for accurate reconstruction with or without automated pullback devices. Information on the rate of change of vessel measurements is also presented, which, when combined with visualization of accurate 3D geometry, provides a unique assessment of coronary compensatory enlargement. This reconstruction technique can be applied in a clinical environment with no major modi®cation.

ASAIO journal (American Society for Artificial Internal Organs : 1992), Jan 22, 2015

The Cleveland Clinic continuous-flow total artificial heart passively regulates itself in regard ... more The Cleveland Clinic continuous-flow total artificial heart passively regulates itself in regard to the relative performance of systemic and pulmonary pumps. The system incorporates real-time monitoring to detect any indication of incipient left or right suction as input for automatic controller response. To recognize suction, the external controller compares the waveforms of modulating speed input and power feedback. Deviations in periodic waveforms indicate sudden changes to flow impedance, which are characteristic of suction events as the pump speed is modulating. Incipient suction is indicated within three seconds of being detected in the power wave form, allowing timely controller response before mean flow is affected. This article describes the results obtained from subjecting the system to severe hemodynamic manipulation during an acute study in a calf.

ASAIO Journal, 2015

The Journal of thoracic and cardiovascular surgery, 2015

The Cleveland Clinic continuous-flow total artificial heart (CFTAH) is a compact, single-piece, v... more The Cleveland Clinic continuous-flow total artificial heart (CFTAH) is a compact, single-piece, valveless, pulsatile pump providing self-regulated hemodynamic output to left/right circulation. We evaluated chronic in vivo pump performance, physiologic and hemodynamic parameters, and biocompatibility of the CFTAH in a well-established calf model. CFTAH pumps have been implanted in 17 calves total. Hemodynamic parameters, pump performance, and device-related adverse events were evaluated during studies and at necropsy. In vivo experiments demonstrated good hemodynamic performance (pump flow, 7.3 ± 0.7 L/min; left atrial pressure, 16 ± 3 mm Hg; right atrial pressure, 17 ± 3 mm Hg; right atrial pressure-left atrial pressure difference, 1 ± 2 mm Hg; mean arterial pressure, 103 ± 7 mm Hg; arterial pulse pressure, 30 ± 11 mm Hg; and pulmonary arterial pressure, 34 ± 5 mm Hg). The CFTAH has operated within design specifications and never failed. With ever-improving pump design, the implants...

Proceedings of the 25th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (IEEE Cat. No.03CH37439), 2003

Our group has recently developed a cone-beam micro-CT imaging system that is capable of imaging a... more Our group has recently developed a cone-beam micro-CT imaging system that is capable of imaging a variety of ex vivo and in vivo structures with varying levels of magnification and spatial resolution. The micro-CT imaging system consists of a microfocal X-ray source, a custom designed 7-axis micro-positioning system and a high-resolution X-ray image intensifier coupled to a 2048×2048 CCD camera.

International journal of cardiac imaging, 2000