Publications by authors named "Brigitta C Brott"

81 Publications

A New Method to Optimize Stent Deployment by High-Definition Intravascular Ultrasound.

J Invasive Cardiol 2021 Jul;33(7):E532-E539

University of Alabama-Birmingham, UAB Heart and vascular Center, 510 20th Street South, FOT: 920, Birmingham, AL 35294 USA. Email:

Objectives: Optimal stent deployment by intravascular ultrasound (IVUS) improves outcome, but it can only be achieved in 50% of patients. We investigated the feasibility and effect of a new method of stent optimization on optimal stent deployment.

Methods: IVUS analyses of 168 coronary segments were performed after angiography-guided stenting (AGS) and stent optimization in 29 patients (30 lesions). Minimum stent area (MSA), stent volume index (SVI), lumen area, external elastic membrane (EEM), and plaque burden (PB) were measured. Stent optimization included post-stent dilation with a balloon sized by high-definition (HD)-IVUS to the distal reference EEM diameter for stent underexpansion or malapposition, and stenting of PB >50% or edge dissection.

Results: After AGS, stent deployment was suboptimal in 77% of patients. After stent optimization, MSA and SVI were significantly larger than AGS. Adequate stent expansion - defined as MSA ≥5.4 mm² or ≥90% of distal reference lumen area - was significantly higher after stent optimization vs AGS (87% vs 56%, respectively; P=.02). Optimal stent deployment - a composite of adequate stent expansion, no malapposition, PB <50% at the stent edges, and no edge dissection - was markedly higher after stent optimization vs AGS (87% vs 35%, respectively; P<.01).

Conclusion: After stent deployment and postdilation, stent results were suboptimal in two-thirds of patients. This simple online stent optimization by HD-IVUS was feasible and resulted in optimal stent deployment in the majority of patients. Randomized studies are warranted to compare the rate of optimal stent deployment and outcomes of this strategy vs other techniques.
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July 2021

Recent advances in nanomaterials for therapy and diagnosis for atherosclerosis.

Adv Drug Deliv Rev 2021 03 9;170:142-199. Epub 2021 Jan 9.

Department of Biomedical Engineering, The University of Alabama at Birmingham, Birmingham, AL, United States. Electronic address:

Atherosclerosis is a chronic inflammatory disease driven by lipid accumulation in arteries, leading to narrowing and thrombosis. It affects the heart, brain, and peripheral vessels and is the leading cause of mortality in the United States. Researchers have strived to design nanomaterials of various functions, ranging from non-invasive imaging contrast agents, targeted therapeutic delivery systems to multifunctional nanoagents able to target, diagnose, and treat atherosclerosis. Therefore, this review aims to summarize recent progress (2017-now) in the development of nanomaterials and their applications to improve atherosclerosis diagnosis and therapy during the preclinical and clinical stages of the disease.
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http://dx.doi.org/10.1016/j.addr.2021.01.005DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7981266PMC
March 2021

Effects of Crushed Ticagrelor Versus Eptifibatide Bolus Plus Clopidogrel in Troponin-Negative Acute Coronary Syndrome Patients Undergoing Percutaneous Coronary Intervention: A Randomized Clinical Trial.

J Am Heart Assoc 2019 12 26;8(23):e012844. Epub 2019 Nov 26.

Division of Cardiology University of Alabama at Birmingham AL.

Background After a loading dose of ticagrelor, the rate of high on-treatment platelet reactivity remains elevated, which increases periprocedural myocardial infarction and injury. This indicates that faster platelet inhibition with crushed ticagrelor (CTIC) or eptifibatide is needed to reduce high on-treatment platelet reactivity. The efficacy of CTIC versus eptifibatide bolus plus clopidogrel is unknown. Methods and Results A total of 100 P2Y naïve, troponin-negative patients with acute coronary syndrome were randomized to CTIC (180 mg) versus eptifibatide bolus (180 μg/kg×2 intravenous boluses) plus clopidogrel (600 mg) at the time of percutaneous coronary intervention. High on-treatment platelet reactivity was markedly higher with CTIC versus eptifibatide bolus plus clopidogrel (42% versus 0%; <0.001) at 30 minutes and persisted up to 2 hours (12% versus 0%; =0.01, respectively). Platelet aggregation by adenosine diphosphate dropped faster from baseline with eptifibatide bolus plus clopidogrel versus CTIC (0.5 versus 2 hours, respectively) and was higher with CTIC versus eptifibatide bolus plus clopidogrel at 0.5, 2, and 4 hours after loading dose (53±12% versus 1.3±2%; 35±11% versus 0.34±1.0%; and 23±9% versus 3.5±2%, respectively; <0.001). Eptifibatide bolus plus clopidogrel, but not CTIC, significantly inhibited platelet aggregation induced by thrombin-receptor activating peptide. Periprocedural myocardial infarction and injury was higher with CTIC versus eptifibatide bolus plus clopidogrel (48% versus 28%, respectively; =0.035). Post-percutaneous coronary intervention hemoglobin levels were not different between groups. Conclusions Eptifibatide bolus plus clopidogrel led to faster and more potent platelet inhibition than CTIC and reduced periprocedural myocardial infarction and injury in troponin-negative acute coronary syndrome patients undergoing percutaneous coronary intervention, with no significant hemoglobin drop after percutaneous coronary intervention. Clinical Trial Registration URL: http://www.clinicaltrials.gov. Unique identifier: NCT02925923.
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http://dx.doi.org/10.1161/JAHA.119.012844DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6912971PMC
December 2019

Risk of Major Adverse Cardiovascular Events and Major Hemorrhage Among White and Black Patients Undergoing Percutaneous Coronary Intervention.

J Am Heart Assoc 2019 11 8;8(22):e012874. Epub 2019 Nov 8.

Department of Neurology University of Alabama at Birmingham AL.

Background Data on racial disparities in major adverse cardiovascular events (MACE) and major hemorrhage (HEM) after percutaneous coronary intervention are limited. Factors contributing to these disparities are unknown. Methods and Results PRiME-GGAT (Pharmacogenomic Resource to Improve Medication Effectiveness-Genotype-Guided Antiplatelet Therapy) is a prospective cohort. Patients aged ≥18 years undergoing percutaneous coronary intervention were enrolled and followed for up to 1 year. Racial disparities in risk of MACE and HEM were assessed using an incident rate ratio. Sequential cumulative adjustment analyses were performed to identify factors contributing to these disparities. Data from 919 patients were included in the analysis. Compared with white patients, black patients (n=203; 22.1% of the cohort) were younger and were more likely to be female, to be a smoker, and to have higher body mass index, lower socioeconomic status, higher prevalence of diabetes mellitus and moderate to severe chronic kidney disease, and presentation with acute coronary syndrome and to undergo urgent percutaneous coronary intervention. The incident rates of MACE (34.1% versus 18.2% per 100 person-years, <0.001) and HEM (17.7% versus 10.3% per 100 person-years, =0.02) were higher in black patients. The incident rate ratio was 1.9 (95% CI, 1.3-2.6; <0.001) for MACE and 1.7 (95% CI, 1.1-2. 7; =0.02) for HEM. After adjustment for nonclinical and clinical factors, black race was not significantly associated with outcomes. Rather, differences in socioeconomic status, comorbidities, and coronary heart disease severity were attributed to racial disparities in outcomes. Conclusions Despite receiving similar treatment, racial disparities in MACE and HEM still exist. Opportunities exist to narrow these disparities by mitigating the identified contributors.
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http://dx.doi.org/10.1161/JAHA.119.012874DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6915255PMC
November 2019

Myocardial rupture after small acute myocardial infarction in the absence of coronary artery disease.

Cardiovasc Pathol 2018 Nov - Dec;37:26-29. Epub 2018 Aug 25.

Division of Cardiovascular Disease, University of Alabama at Birmingham. Electronic address:

A 73-year-old woman with a past medical history of hypertension suffered a cardiac arrest. After successful resuscitation, she was hypotensive and tachycardic and the ECG showed ST elevation in the inferior and lateral precordial leads. Coronary angiography did not show evidence of obstructive coronary artery disease. A bedside echocardiogram demonstrated a large pericardial effusion with signs of cardiac tamponade. The echocardiogram and subsequent aortic root angiography did not reveal evidence of dissection. Pericardiocentesis removed 700 cc of bloody fluid with relief of tamponade. A few minutes later the patient again arrested. Fluid was again drained but she suffered recurrent hemodynamic collapse and could not be resuscitated. Autopsy revealed a small transmural myocardial infarction with external rupture and hemopericardium. There was only mild coronary artery disease without evidence of plaque rupture. This case illustrates that mild coronary artery disease and a small myocardial infarction can lead to catastrophic mechanical complications.
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http://dx.doi.org/10.1016/j.carpath.2018.08.004DOI Listing
January 2019

Drug-Eluting Balloon Therapy for In-Stent Restenosis of Drug-Eluting Stents: Choose and Prepare the Appropriate Lesion.

JACC Cardiovasc Interv 2018 05;11(10):979-980

Division of Cardiovascular Disease, The University of Alabama at Birmingham, Birmingham, Alabama.

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http://dx.doi.org/10.1016/j.jcin.2018.03.014DOI Listing
May 2018

Myocardial tissue characterization by combining late gadolinium enhancement imaging and percent edema mapping: a novel T2 map-based MRI method in canine myocardial infarction.

Eur Radiol Exp 2018 16;2(1). Epub 2018 Mar 16.

1Division of Cardiovascular Imaging, Department of Radiology and Radiological Science, Medical University of South Carolina, 25 Courtenay Dr, Charleston, SC 29425 USA.

Background: Assessing the extent of ischemic and reperfusion-associated myocardial injuries remains challenging with current magnetic resonance imaging (MRI) techniques. Our aim was to develop a tissue characterization mapping (TCM) technique by combining late gadolinium enhancement (LGE) with our novel percent edema mapping (PEM) approach to enable the classification of tissue represented by MRI voxels as healthy, myocardial edema (ME), necrosis, myocardial hemorrhage (MH), or scar.

Methods: Six dogs underwent closed-chest myocardial infarct (MI) generation. Serial MRI scans were performed post-MI on days 3, 4, 6, 14, and 56, including T2 mapping and LGE. Dogs were sacrificed on day 4 ( = 4, acute MI) or day 56 ( = 2, chronic MI). TCMs were generated based on a voxel classification algorithm taking into account signal intensity from LGE and T2-based estimation of ME. TCM-based MI and MH were validated with post mortem triphenyl tetrazolium chloride (TTC) staining. Pearson's correlation and Bland-Altman analyses were performed.

Results: The MI, ME, and MH measured by TCM were 13.4% [25-75 percentile 1.6-28.8], 28.1% [2.1-37.5] and 4.3% [1.0-11.3], respectively. TCM measured higher MH and MI compared to TTC ( = 0.0033 and = 0.0007, respectively). MH size was linearly correlated with MI size by both MRI ( = 0.9528, < 0.0001) and TTC ( = 0.9625, < 0.0001). MH quantification demonstrated good agreement between TCM and TTC ( = 0.8766, < 0.0001, 2.4% overestimation by TCM). A similar correlation was observed for MI size ( = 0.9429, < 0.0001, 6.1% overestimation by TCM).

Conclusions: Preliminary results suggest that the TCM method is feasible for the in vivo localization and quantification of various MI-related tissue components.
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http://dx.doi.org/10.1186/s41747-018-0037-6DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5909369PMC
March 2018

Multisite Investigation of Outcomes With Implementation of CYP2C19 Genotype-Guided Antiplatelet Therapy After Percutaneous Coronary Intervention.

JACC Cardiovasc Interv 2018 01 1;11(2):181-191. Epub 2017 Nov 1.

Department of Medicine, University of Maryland, Baltimore, Maryland.

Objectives: This multicenter pragmatic investigation assessed outcomes following clinical implementation of CYP2C19 genotype-guided antiplatelet therapy after percutaneous coronary intervention (PCI).

Background: CYP2C19 loss-of-function alleles impair clopidogrel effectiveness after PCI.

Methods: After clinical genotyping, each institution recommended alternative antiplatelet therapy (prasugrel, ticagrelor) in PCI patients with a loss-of-function allele. Major adverse cardiovascular events (defined as myocardial infarction, stroke, or death) within 12 months of PCI were compared between patients with a loss-of-function allele prescribed clopidogrel versus alternative therapy. Risk was also compared between patients without a loss-of-function allele and loss-of-function allele carriers prescribed alternative therapy. Cox regression was performed, adjusting for group differences with inverse probability of treatment weights.

Results: Among 1,815 patients, 572 (31.5%) had a loss-of-function allele. The risk for major adverse cardiovascular events was significantly higher in patients with a loss-of-function allele prescribed clopidogrel versus alternative therapy (23.4 vs. 8.7 per 100 patient-years; adjusted hazard ratio: 2.26; 95% confidence interval: 1.18 to 4.32; p = 0.013). Similar results were observed among 1,210 patients with acute coronary syndromes at the time of PCI (adjusted hazard ratio: 2.87; 95% confidence interval: 1.35 to 6.09; p = 0.013). There was no difference in major adverse cardiovascular events between patients without a loss-of-function allele and loss-of-function allele carriers prescribed alternative therapy (adjusted hazard ratio: 1.14; 95% confidence interval: 0.69 to 1.88; p = 0.60).

Conclusions: These data from real-world observations demonstrate a higher risk for cardiovascular events in patients with a CYP2C19 loss-of-function allele if clopidogrel versus alternative therapy is prescribed. A future randomized study of genotype-guided antiplatelet therapy may be of value.
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http://dx.doi.org/10.1016/j.jcin.2017.07.022DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5775044PMC
January 2018

Ticagrelor and Eptifibatide Bolus Versus Ticagrelor and Eptifibatide Bolus With 2-Hour Infusion in High-Risk Acute Coronary Syndromes Patients Undergoing Early Percutaneous Coronary Intervention.

J Am Heart Assoc 2017 Jun 13;6(6). Epub 2017 Jun 13.

Division of Cardiology, University of Alabama at Birmingham, AL

Background: In patients with non-ST-segment elevation acute coronary syndromes, inhibition of platelet aggregation (IPA) with a potent P2Y inhibitor, ticagrelor, was inferior to tirofiban infusion at 2 hours, indicating that glycoprotein IIb/IIIa inhibitors are still needed. Ticagrelor and eptifibatide bolus only may maximally inhibit platelet aggregation and decrease bleeding, but IPA with ticagrelor and eptifibatide bolus versus 2-hour infusion is unknown.

Methods And Results: A total of 70 P2Y-naïve patients, with high-risk non-ST-segment elevation acute coronary syndromes, were randomized to ticagrelor and eptifibatide bolus (group 1) versus ticagrelor and eptifibatide bolus with 2-hour infusion (group 2). Levels of IPA with ADP, thrombin receptor-activating peptide, collagen, and high on-treatment platelet reactivity were measured by light transmission aggregometry at baseline and at 2, 6, and 24 hours after percutaneous coronary intervention in both groups. The primary end point, IPA with ADP 20 μmol/L at 2 hours, was 99.59±0.43% in group 1 versus 99.88±1.0% in group 2 (<0.001 for noninferiority). High on-treatment platelet reactivity with ADP was zero at 2, 6, and 24 hours in both groups. IPA levels with ADP, thrombin receptor-activating peptide, and collagen were significantly higher at 2 and 6 hours than at 24 hours in both groups. Periprocedural myocardial infarction was not significantly different between the groups. Hemoglobin level was significantly less at 24 hours versus baseline in group 2 (13.35±1.8 versus 12.38±1.8 g/dL, respectively; <0.01).

Conclusions: Ticagrelor and eptifibatide bolus maximally inhibited platelet aggregation at 2 hours, which was associated with no significant hemoglobin drop after percutaneous coronary intervention. This obviates the need for eptifibatide 2-hour infusion and might decrease bleeding complications.

Clinical Trial Registration: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01919723.
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http://dx.doi.org/10.1161/JAHA.117.005562DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5669172PMC
June 2017

The MRI characteristics of the no-flow region are similar in reperfused and non-reperfused myocardial infarcts: an MRI and histopathology study in swine.

Eur Radiol Exp 2017 29;1(1). Epub 2017 Jun 29.

1Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, MCLM 556, Birmingham, AL 35294-0005 USA.

Background: The no-flow region (NF) visualised by magnetic resonance imaging (MRI) in myocardial infarction (MI) has been explained as the product of reperfusion-injury-induced microvascular obstruction. However, a similar MRI phenomenon occurs in non-reperfused MI. Accordingly, our purpose was to compare the MRI and histopathologic characteristics of the NF in reperfused and non-reperfused MIs.

Methods: Reperfused ( = 7) and non-reperfused MIs ( = 7) were generated in swine by percutaneous balloon occlusion and microsphere embolisation techniques. Four days post-MI, animals underwent myocardial T2-mapping, early and serial late gadolinium enhancement MRI. MI and NF were compared between the models using the independent samples test. Serial measurements were analysed using repeated measures analysis of variance. Triphenyltetrazolium chloride (TTC) macroscopic and microscopic histopathologic assessment was also performed.

Results: The MI size in the reperfused and non-reperfused groups was 17.1 ± 3.4 ml and 19.4 ± 8.1 ml, respectively ( = 0.090), in agreement with TTC assessment ( = 0.216;  = 0.484), and the NF size was 7.7 ± 2.4 ml and 8.1 ± 1.9 ml, respectively ( = 0.211). Compared to the reference 2-min post-contrast measurement, the NF size was significantly reduced at 20 min in the reperfused group and at 25 min in the non-reperfused group (both  < 0.001). Nevertheless, the NF was still detectable at 45 min after injection. No significant T2 difference was observed between the groups ( > 0.326). Histopathologic assessment revealed extensive calcification and hemosiderin deposition in the NF of the reperfused MI, but not in the non-reperfused MI.

Conclusions: The NF in non-reperfused and reperfused MIs have similar characteristics on MRI despite the different pathophysiologic and underlying histopathologic conditions, indicating that the presence of the NF alone cannot differentiate between these two types of MI.
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http://dx.doi.org/10.1186/s41747-017-0001-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5909333PMC
June 2017

Safety of hydrophilic guidewires used for side-branch protection during stenting and proximal optimization technique in coronary bifurcation lesions.

Cardiovasc Revasc Med 2016 Oct - Nov;17(7):456-462. Epub 2016 Apr 22.

Division of Cardiology, University of Alabama-Birmingham, USA. Electronic address:

Background And Propose: In coronary bifurcation lesions (CBL), hydrophilic guidewires used for side-branch (SB) protection can be withdrawn from underneath the stent easier than other wires. However, the safety of which has not been investigated.

Methods/materials: We performed scanning electron microscopic (SEM) examination of hydrophilic wires - the Whisper and Runthrough wires - used for SB protection during stenting and proximal optimization technique (POT) in 30 patients with CBL. The distal 15cm of the wire was examined every 1mm by SEM and 4500 segments were analyzed to investigate for wire fracture, polymer shearing (PS), and its correlations with post-stenting creatine kinase (CK)-MB release.

Results: SEM examination showed no evidence for wire fracture. The total area of PS and the largest defect on the wire were significantly larger with the Whisper wire versus the Runthrough wire (0.15±0.04mm vs. 0.026±0.01mm and 0.04±0.05mm vs. 0.01±0.01mm; P<0.05, respectively). The total length of PS and the longest defect on the wire were significantly longer with the Whisper wire vs. the Runthrough wire (12.1±14.5mm vs. 2.7±3.0mm and 2.9±4.2mm vs. 1.0±1.2mm; P<0.05, respectively), but there were weak correlations between the extents of PS with CK-MB release.

Conclusions: Hydrophilic guidewires may be safely used for SB protection during stenting and POT in CBLs. The extent of PS was significantly greater with the Whisper wire than with the Runthrough wire, but its correlation with post-stenting CK-MB release was weak.
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http://dx.doi.org/10.1016/j.carrev.2016.04.006DOI Listing
February 2017

The Return of Coronary Vasomotion After Bioresorbable Scaffold Implantation.

Authors:
Brigitta C Brott

JACC Cardiovasc Interv 2016 Apr;9(7):742-4

Division of Cardiovascular Disease, Interventional Cardiology, University of Alabama at Birmingham, Birmingham, Alabama. Electronic address:

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http://dx.doi.org/10.1016/j.jcin.2016.02.007DOI Listing
April 2016

Novel Multifunctional Nanomatrix Reduces Inflammation in Dynamic Conditions in Vitro and Dilates Arteries ex Vivo.

ACS Appl Mater Interfaces 2016 Mar 17;8(8):5178-87. Epub 2016 Feb 17.

School of Medicine, Division of Cardiology, Emory University , Atlanta, Georgia 30322, United States.

Inflammatory responses play a critical role in tissue-implant interactions, often limiting current implant utility. This is particularly true for cardiovascular devices. Existing stent technology does little to avoid or mitigate inflammation or to influence the vasomotion of the artery after implantation. We have developed a novel endothelium-mimicking nanomatrix composed of peptide amphiphiles that enhances endothelialization while decreasing both smooth muscle cell proliferation and platelet adhesion. Here, we evaluated whether the nanomatrix could prevent inflammatory responses under static and physiological flow conditions. We found that the nanomatrix reduced monocyte adhesion to endothelial cells and expression of monocyte inflammatory genes (TNF-α, MCP-1, IL-1β, and IL-6). Furthermore, the nitric-oxide releasing nanomatrix dramatically attenuated TNF-α-stimulated inflammatory responses as demonstrated by significantly reduced monocyte adhesion and inflammatory gene expression in both static and physiological flow conditions. These effects were abolished by addition of a nitric oxide scavenger. Finally, the nanomatrix stimulated vasodilation in intact rat mesenteric arterioles after constriction with phenylephrine, demonstrating the bioavailability and bioactivity of the nanomatrix, as well as exhibiting highly desired release kinetics. These results demonstrate the clinical potential of this nanomatrix by both preventing inflammatory responses and promoting vasodilation, critical improvements in stent and cardiovascular device technology.
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http://dx.doi.org/10.1021/acsami.6b00565DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5179142PMC
March 2016

A Bigger Artery Is Not Better: Predicting Coronary Plaque Rupture.

Authors:
Brigitta C Brott

JACC Cardiovasc Imaging 2015 Oct;8(10):1188-1190

Division of Cardiovascular Disease, University of Alabama at Birmingham, Birmingham, Alabama. Electronic address:

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http://dx.doi.org/10.1016/j.jcmg.2015.07.007DOI Listing
October 2015

In vivo monitoring of the inflammatory response in a stented mouse aorta model.

J Biomed Mater Res A 2016 Jan 18;104(1):227-38. Epub 2015 Sep 18.

Department of Mechanical Engineering and Materials Science and Engineering, Cyprus University of Technology, Limassol, 3036, Cyprus.

The popularity of vascular stents continues to increase for a variety of applications, including coronary, lower limb, renal, carotid, and neurovascular disorders. However, their clinical effectiveness is hindered by numerous postdeployment complications, which may stimulate inflammatory and fibrotic reactions. The purpose of this study was to evaluate the vessel inflammatory response via in vivo imaging in a mouse stent implantation model. Corroded and noncorroded self-expanding miniature nitinol stents were implanted in mice abdominal aortas, and novel in vivo imaging techniques were used to assess trafficking and accumulation of fluorescent donor monocytes as well as cellular proliferation at the implantation site. Monocytes were quantitatively tracked in vivo and found to rapidly clear from circulation within hours after injection. Differences were found between the test groups with respect to the numbers of recruited monocytes and the intensity of the resulting fluorescent signal. Image analysis also revealed a subtle increase in matrix metalloproteinase activity in corroded compared with the normal stented aortas. In conclusion, this study has been successful in developing a murine stent inflammation model and applying novel in vivo imaging tools and methods to monitor the complex biological processes of the host vascular wall response.
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http://dx.doi.org/10.1002/jbm.a.35560DOI Listing
January 2016

Age-independent myocardial infarct quantification by signal intensity percent infarct mapping in swine.

J Magn Reson Imaging 2016 Apr 10;43(4):911-20. Epub 2015 Sep 10.

Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, Birmingham, Alabama, USA.

Purpose: To test whether signal intensity percent infarct mapping (SI-PIM) accurately determines the size of myocardial infarct (MI) regardless of infarct age.

Materials And Methods: Forty-five swine with reperfused MI underwent 1.5T late gadolinium enhancement (LGE) magnetic resonance imaging (MRI) after bolus injection of 0.2 mmol/kg Gd(DTPA) on days 2-62 following MI. Animals were classified into acute, healing, and healed groups by pathology. Infarct volume (IV) and infarct fraction (IF) were determined by two readers, using binary techniques (including 2-5 standard deviations [SD] above the remote, and full-width at half-maximum) and the SI-PIM method. Triphenyl-tetrazolium-chloride staining (TTC) was performed as reference. Bias (percent under/overestimation of IV relative to TTC) of each quantification method was calculated. Bland-Altman analysis was done to test the accuracy of the quantification methods, while intraclass correlation coefficient (ICC) analysis was done to assess intra- and interobserver agreement.

Results: Bias of the MRI quantification methods do not depend on the age of the MI. Full-width at half-maximum (FWHM) and SI-PIM gave the best estimate of MI volume determined by the reference TTC (P-values for the FWHM and SI-PIM methods were 0.183, 0.26, 0.95, and 0.073, 0.091, 0.73 in Group 1, Group 2, and Group 3, respectively), while using any of the binary thresholds of 2-4 SDs above the remote myocardium showed significant overestimation. The 5 SD method, however, provided similar IV compared to TTC and was shown to be independent of the size and age of MI. ICC analysis showed excellent inter- and intraobserver agreement between the readers.

Conclusion: Our results indicate that the SI-PIM method can accurately determine MI volume regardless of the pathological stage of MI. Once tested, it may prove to be useful for the clinic.
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http://dx.doi.org/10.1002/jmri.25046DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4786470PMC
April 2016

Evaluation of ciprofloxacin and metronidazole encapsulated biomimetic nanomatrix gel on and .

Biomater Res 2015 Jun;19

Department of Pediatric Dentistry, University of Alabama at Birmingham, SDB 304B, 1720 2nd Ave S, Birmingham, AL 35294-0007, USA.

Background: A triple antibiotic mixture (ciprofloxacin; CF, metronidazole; MN, and minocycline; MC) has been used for dental root canal medicaments in pulp regeneration therapy. However, tooth discolorations, cervical root fractures, and inadequate pulp-dentin formation have been reported due to the triple antibiotic regimen. Therefore, an antibiotic encapsulated biomimetic nanomatrix gel was developed to minimize the clinical limitations and maximize a natural healing process in root canal infections. In this study, minimal bacterial concentrations (MBC) of the selected antibiotics (CF and MN) were tested in 14 representative endodontic bacterial species. Then MBC of each CF and MN were separately encapsulated within the injectable self-assembled biomimetic nanomatrix gel to evaluate antibacterial level on and .

Results: Antibiotic concentrations lower than 0.2 µg/mL of CF and MN demonstrated antibacterial activity on the 14 endodontic species. Furthermore, 6 different concentrations of CF and MN separately encapsulated with the injectable self-assembled biomimetic nanomatrix gel demonstrated antibacterial activity on and at the lowest tested concentration of 0.0625 µg/mL.

Conclusions: These results suggest that each CF and MN encapsulated within the injectable self-assembled biomimetic nanomatrix gel demonstrated antibacterial effects, which could be effective for the root canal disinfection while eliminating MC. In the long term, the antibiotic encapsulated injectable self-assembled biomimetic nanomatrix gel can provide a multifunctional antibiotic delivery method with potential root regeneration. Further studies are currently underway to evaluate the effects of combined CF and MN encapsulated within the injectable self-assembled biomimetic nanomatrix gel on clinical samples.
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http://dx.doi.org/10.1186/s40824-015-0032-4DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4527351PMC
June 2015

Obesity and percutaneous coronary intervention outcomes: beware the extremes.

Catheter Cardiovasc Interv 2015 May;85(6):959-60

Heart South Cardiovascular Group, Alabaster, Alabama; Department of Biostatistics, University of Alabama at Birmingham, Birmingham, Alabama.

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http://dx.doi.org/10.1002/ccd.25933DOI Listing
May 2015

Percutaneous coronary intervention: ever closer to real world silver bullets!?

Catheter Cardiovasc Interv 2015 Apr;85(5):807-8

Interventional Cardiovascular Section, Heart South Cardiovascular Group, Alabaster, Alabama; Department of Biostatistics, University of Alabama at Birmingham, Birmingham, Alabama.

Bare metal and early drug eluting stents have not meaningfully reduced subsequent rates of death and myocardial infarction compared to balloon angioplasty. Second generation drug eluting stents are associated with meaningful reductions in death and myocardial infarction compared to first generation drug eluting stents.
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http://dx.doi.org/10.1002/ccd.25885DOI Listing
April 2015

Prevention of myocardial stunning during percutaneous coronary interventions: novel insights from pre-treatment with glucagon-like peptide-1.

Authors:
Brigitta C Brott

JACC Cardiovasc Interv 2015 Feb;8(2):302-304

Section of Interventional Cardiology, University of Alabama at Birmingham, Birmingham, Alabama. Electronic address:

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http://dx.doi.org/10.1016/j.jcin.2014.12.218DOI Listing
February 2015

Can femoral access bleeding outcomes be improved?

Catheter Cardiovasc Interv 2015 Feb;85(3):380-1

Heart South Cardiovascular Group, Alabaster, Alabama; University of Alabama at Birmingham, Birmingham, Alabama.

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http://dx.doi.org/10.1002/ccd.25808DOI Listing
February 2015

Transdiaphragmatic rupture of hepatic abscess producing purulent pericarditis and pericardial tamponade.

Circulation 2015 Jan;131(1):e1-2

From the Division of Cardiovascular Diseases, University of Alabama at Birmingham, Birmingham, AL.

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http://dx.doi.org/10.1161/CIRCULATIONAHA.114.012078DOI Listing
January 2015

Optimal DAPT duration: each in their own time.

Catheter Cardiovasc Interv 2015 Jan;85(1):41-2

Heart South Cardiovascular Group, Alabaster, AL and University of Alabama at Birmingham, Birmingham, AL, USA.

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http://dx.doi.org/10.1002/ccd.25737DOI Listing
January 2015

Evaluation of the effect of expansion and shear stress on a self-assembled endothelium mimicking nanomatrix coating for drug eluting stents in vitro and in vivo.

Biofabrication 2014 Sep 22;6(3):035019. Epub 2014 Jul 22.

Department of Biomedical Engineering, University of Alabama at Birmingham, Alabama, USA.

Coating stability is increasingly recognized as a concern impacting the long-term effectiveness of drug eluting stents (DES). In particular, unstable coatings have been brought into focus by a recently published report (Denardo et al 2012 J. Am. Med. Assoc. 307 2148-50). Towards the goal of overcoming current challenges of DES performance, we have developed an endothelium mimicking nanomatrix coating composed of peptide amphiphiles that promote endothelialization, but limit smooth muscle cell proliferation and platelet adhesion. Here, we report a novel water evaporation based method to uniformly coat the endothelium mimicking nanomatrix onto stents using a rotational coating technique, thereby eliminating residual chemicals and organic solvents, and allowing easy application to even bioabsorbable stents. Furthermore, the stability of the endothelium mimicking nanomatrix was analyzed after force experienced during expansion and shear stress under simulated physiological conditions. Results demonstrate uniformity and structural integrity of the nanomatrix coating. Preliminary animal studies in a rabbit model showed no flaking or peeling, and limited neointimal formation or restenosis. Therefore, it has the potential to improve the clinical performance of DES by providing multifunctional endothelium mimicking characteristics with structural integrity on stent surfaces.
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http://dx.doi.org/10.1088/1758-5082/6/3/035019DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4156883PMC
September 2014

Left anterior descending coronary artery occlusion secondary to metastatic squamous cell carcinoma presenting as ST-segment-elevation myocardial infarction.

Circulation 2014 Jun;129(24):e652-3

From the Division of Cardiovascular Diseases, Department of Internal Medicine, University of Alabama at Birmingham, Birmingham.

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http://dx.doi.org/10.1161/CIRCULATIONAHA.114.009157DOI Listing
June 2014

Impact of head rotation on the individualized common carotid flow and carotid bifurcation hemodynamics.

IEEE J Biomed Health Inform 2014 May;18(3):783-9

This paper aims at evaluating the changes that head rotation poses on morphological and flow characteristics of the carotid bifurcation (CB) and on the distribution of parameters that are regarded as important in atherosclerosis development, such as relative particle residence time (RRT), normalized oscillatory shear index (nOSI), and helicity (HL). Using a subject-specific approach, six healthy volunteers were MR-scanned in two head postures: supine neutral and prone with rightward head rotation. Cross-sectional flow velocity distribution was obtained using phase-contrast MRI at the common carotid artery (CCA). Our results indicate that peak systolic flow rate is reduced at the prone position in most cases for both CCAs. Morphological MR images are used to segment and construct the CB models. Numerical simulations are performed and areas exposed to high helicity or unfavorable hemodynamics are calculated. Head rotation affects the instantaneous spatial extent of high helicity regions. Posture-related observed differences in the distribution of nOSI and RRT suggest that inlet flow waveform tends to moderate geometry-induced changes in the qualitative and quantitative distribution of atherosclerosis-susceptible wall regions. Overall, presented results indicate that an individualized approach is required to fully assess the postural role in atherosclerosis development and in complications arising in stenotic and stented vessels.
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http://dx.doi.org/10.1109/JBHI.2014.2305575DOI Listing
May 2014

Infarct density distribution by MRI in the porcine model of acute and chronic myocardial infarction as a potential method transferable to the clinic.

Int J Cardiovasc Imaging 2014 Jun 10;30(5):937-48. Epub 2014 Apr 10.

Department of Biochemistry and Molecular Genetics, University of Alabama at Birmingham, MCLM 556, Birmingham, AL, 35294-0005, USA.

To study the feasibility of a myocardial infarct (MI) quantification method [signal intensity-based percent infarct mapping (SI-PIM)] that is able to evaluate not only the size, but also the density distribution of the MI. In 14 male swine, MI was generated by 90 min of closed-chest balloon occlusion followed by reperfusion. Seven (n = 7) or 56 (n = 7) days after reperfusion, Gd-DTPA-bolus and continuous-infusion enhanced late gadolinium enhancement (LGE) MRI, and R1-mapping were carried out and post mortem triphenyl-tetrazolium-chloride (TTC) staining was performed. MI was quantified using binary [2 or 5 standard deviation (SD)], SI-PIM and R1-PIM methods. Infarct fraction (IF), and infarct-involved voxel fraction (IIVF) were determined by each MRI method. Bias of each method was compared to the TTC technique. The accuracy of MI quantification did not depend on the method of contrast administration or the age of the MI. IFs obtained by either of the two PIM methods were statistically not different from the IFs derived from the TTC measurements at either MI age. IFs obtained from the binary 2SD method overestimated IF obtained from TTC. IIVF among the three different PIM methods did not vary, but with the binary methods the IIVF gradually decreased with increasing the threshold limit. The advantage of SI-PIM over the conventional binary method is the ability to represent not only IF but also the density distribution of the MI. Since the SI-PIM methods are based on a single LGE acquisition, the bolus-data-based SI-PIM method can effortlessly be incorporated into the clinical image post-processing procedure.
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http://dx.doi.org/10.1007/s10554-014-0408-xDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4144864PMC
June 2014

Thromboaspiration and IIb/IIIa therapy in STEMI: abciximab redux?

Catheter Cardiovasc Interv 2013 Oct;82(4):612-3

Heart South Cardiovascular Group, Alabaster, Alabama; University of Alabama at Birmingham, Birmingham, Alabama.

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http://dx.doi.org/10.1002/ccd.25156DOI Listing
October 2013

ACP Journal Club. Adding aspirin to clopidogrel worsened outcomes in PCI patients receiving oral anticoagulants.

Authors:
Brigitta C Brott

Ann Intern Med 2013 Jun;158(12):JC6

University of Alabama at Birmingham, Birmingham, AL, USA.

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http://dx.doi.org/10.7326/0003-4819-158-12-201306180-02006DOI Listing
June 2013
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