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ABSTRACT: Endovascular repair of the aorta has traditionally been limited to the abdominal aorta and, more recently, the descending thoracic aorta. However, recently hybrid repairs (a combination of open surgical and endovascular repair) have made endovascular repair of the aortic arch possible. Hybrid repair of the aortic arch typically involves an open surgical debranching procedure that allows for revascularization of the aortic arch vessels and subsequent endovascular stent placement. These approaches avoid the deep hypothermic circulatory arrest required for full, open surgical repair of the aortic arch. In hybrid repairs, the stent landing zone determines which branch vessels will be covered and therefore need revascularization. This article will review the preprocedure assessment with computed tomography angiography, techniques for revascularization and postprocedure complications.
Expert Review of Cardiovascular Therapy 05/2013; 11(5):589-606.
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ABSTRACT: Acute coronary syndrome (ACS) is a major cause of morbidity and mortality worldwide. New serological biomarkers, such as troponins, have improved the diagnosis of ACS; however, the diagnosis of ACS can still be difficult as there is marked heterogeneity in its presentation and significant overlap with other disorders presenting with chest pain. Evidence is accumulating that cardiac MRI provides information that can aid the detection and differential diagnosis of ACS, guide clinical decision-making and improve risk-stratification after an event. In this review, we present the relevant cardiac MRI techniques that can be used to detect ACS accurately, provide differential diagnosis, identify the sequelae of ACS, and determine prognostication after ACS.
Future Cardiology 05/2013; 9(3):351-70.
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Journal of the American College of Cardiology 04/2013; · 14.16 Impact Factor
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Meng Yin,
Arunark Kolipaka,
David A Woodrum,
Kevin J Glaser,
Anthony J Romano,
Armando Manduca,
Jayant A Talwalkar, Philip A Araoz,
Kiaran P McGee,
Nandan S Anavekar,
Richard L Ehman
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ABSTRACT: PURPOSE: To investigate the influence of portal pressure on the shear stiffness of the liver and spleen in a well-controlled in vivo porcine model with magnetic resonance elastography (MRE). A significant correlation between portal pressure and tissue stiffness could be used to noninvasively assess increased portal venous pressure (portal hypertension), which is a frequent clinical condition caused by cirrhosis of the liver and is responsible for the development of many lethal complications. MATERIALS AND METHODS: During multiple intraarterial infusions of Dextran-40 in three adult domestic pigs in vivo, 3D abdominal MRE was performed with left ventricle and portal catheters measuring blood pressure simultaneously. Least-squares linear regressions were used to analyze the relationship between tissue stiffness and portal pressure. RESULTS: Liver and spleen stiffness have a dynamic component that increases significantly following an increase in portal or left ventricular pressure. Correlation coefficients with the linear regressions between stiffness and pressure exceeded 0.8 in most cases. CONCLUSION: The observed stiffness-pressure relationship of the liver and spleen could provide a promising noninvasive method for assessing portal pressure. Using MRE to study the tissue mechanics associated with portal pressure may provide new insights into the natural history and pathophysiology of hepatic diseases and may have significant diagnostic value in the future. J. Magn. Reson. Imaging 2013;. © 2013 Wiley Periodicals, Inc.
Journal of Magnetic Resonance Imaging 02/2013; · 2.70 Impact Factor
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ABSTRACT: PURPOSE: In a previous study, the 2006 appropriateness criteria (AC) for cardiac CT were applied to 251 patients. It was found that 46% of patients could not be classified, and two observers showed only fair agreement (κ = 0.31) on the assigned appropriateness rating (appropriate, inappropriate, uncertain, or not classifiable). The conclusion was that the 2006 AC were difficult to apply. The AC were revised in 2010. The aim of this study was to determine if the rate of patients not classifiable and interobserver variability had decreased to the point at which the AC could be reasonably applied. METHODS: Medical records of the 251 patients who were classified using the 2006 AC were reviewed by two observers, who attempted to assign the patients' indications using the 2010 AC. Patients for whom no indications could be found were deemed not classifiable. A third observer settled disagreements. The numbers of patients not classifiable using the 2006 and 2010 criteria and the number of patients on whom the two reviewers disagreed on indications were compared using McNemar's test. RESULTS: One hundred fifteen patients (46%) were not classifiable using the 2006 AC. With the 2010 AC, the number of patients not classifiable decreased to 39 (16%) (P < .001). With the 2006 criteria, the observers disagreed on specific indications for 152 patients (61%). With the 2010 criteria, the observers disagreed for 118 patients (47%) (P = .002). CONCLUSIONS: Using the 2010 AC, the number of patients not classifiable and the number of disagreements decreased. Although the rate of patients not classifiable has decreased to an acceptable level, the interobserver variability remains concerning.
Journal of the American College of Radiology: JACR 01/2013;
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ABSTRACT: Quadricuspid pulmonary valve (QPV) is a rare congenital cardiac entity. The recognition of QPV has clinical significance as it can cause pulmonary valve dysfunction. It is also important to recognize this condition in patients undergoing the Ross procedure. We report a case of QPV diagnosed by computed tomography with associated pulmonary stenosis and right ventricular hypertrophy.
Journal of thoracic imaging 11/2012; 27(6):W171-3. · 1.42 Impact Factor
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ABSTRACT: Valvular disease is estimated to account for as many as 20% of cardiac surgical procedures performed in the United States. It may be congenital in origin or secondary to another disease process. One congenital anomaly, bicuspid aortic valve, is associated with increased incidence of stenosis, regurgitation, endocarditis, and aneurysmal dilatation of the aorta. A bicuspid valve has two cusps instead of the normal three; resultant fusion or poor excursion of the valve leaflets may lead to aortic stenosis, the presence of which is signaled by dephasing jets on magnetic resonance (MR) images. Surgery is generally recommended for patients with severe stenosis who are symptomatic or who have significant ventricular dysfunction; transcatheter aortic valve implantation (TAVI) is an emerging therapeutic option for patients who are not eligible for surgical treatment. Computed tomography (CT) is an essential component of preoperative planning for TAVI; it is used to determine the aortic root dimensions, severity of peripheral vascular disease, and status of the coronary arteries. Aortic regurgitation, which is caused by incompetent closure of the aortic valve, likewise leads to the appearance of jets on MR images. The severity of regurgitation is graded on the basis of valvular morphologic parameters; qualitative assessment of dephasing jets at Doppler ultrasonography; or measurements of the regurgitant fraction, volume, and orifice area. Mild regurgitation is managed conservatively, whereas severe or symptomatic regurgitation usually leads to valve replacement surgery, especially in the presence of substantial left ventricular enlargement or dysfunction. Bacterial endocarditis, although less common than aortic stenosis and regurgitation, is associated with substantial morbidity and mortality. Electrocardiographically gated CT reliably demonstrates infectious vegetations and benign excrescences of 1 cm or more on the valve surface, allowing the assessment of any embolic complications. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.325115727/-/DC1. © RSNA, 2012.
Radiographics 09/2012; 32(5):1399-420. · 2.85 Impact Factor
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ABSTRACT: The utility of CT findings in predicting long-term mortality in patients with acute pulmonary embolism (PE) is unknown. The purpose of this study is to retrospectively determine whether three CT findings--increased embolic burden, interventricular septal bowing toward the left ventricle, and right ventricle-to-left ventricle (RV/LV) diameter ratio greater than 1--are independent predictors of long-term all-cause mortality after acute PE.
A total of 1105 patients (47% female; mean age, 63 ± 16 years) with CT scans positive for PE from January 1, 1997, to December 31, 2002, were included. Scans were independently interpreted by two observers, with a third independent observer reviewing discrepant cases. CT findings and clinical information were compared with all-cause mortality using univariate and multivariate logistic regression analyses.
The median duration of survival was 6.2 years following acute PE, with estimated 10-year survival of 37.4%. CT-derived embolic burden was associated with a very small decrease in long-term all-cause mortality in both univariate (hazard ratio [HR], 0.97; p < 0.001) and multivariate (HR, 0.97; p < 0.001) analyses. Interventricular septal bowing and RV/LV diameter ratio were not significantly associated with long-term all-cause mortality.
CT findings are not predictive of decreased long-term survival after acute PE.
American Journal of Roentgenology 06/2012; 198(6):1346-52. · 2.78 Impact Factor
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Journal of the American College of Cardiology 05/2012; 59(21):1849-60. · 14.16 Impact Factor
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ABSTRACT: The purpose of this study was to determine the cardiac phase having the highest coronary sharpness for low and high heart
rate patients scanned with dual source CT (DSCT) and to compare coronary image sharpness over different cardiac phases. DSCT
coronary CT scans for 30 low heart rate (≤70beats per minute- bpm) and 30 high heart rate (>70bpm) patients were reconstructed
into different cardiac phases, starting at 30% and increasing at 5% increments until 70%. A blinded observer graded image
sharpness per coronary segment, from which sharpness scores were produced for the right (RCA), left main (LM), left anterior
descending (LAD), and circumflex (Cx) coronary arteries. For each coronary artery, the phase with maximal image sharpness
was identified with repeated measures analysis of variance. Comparison of coronary sharpness between low and high heart rate
patients was made using generalized estimating equations. For low heart rates the highest sharpness scores for all four vessels
(RCA, LM, LAD, and Cx) were at the 65 or 70% phase, which are end-diastolic cardiac phases. For high heart rates the highest
sharpness scores were between the 35 and 45% phases, which are end-systolic phases. Low heart rate patients had higher coronary
sharpness at most cardiac phases; however, patients with high heart rates had higher coronary sharpness in the 45% phase for
all four vessels (P<0.0001). Using DSCT scanning, optimal image sharpness is obtained in end-diastole at low heart rates and in end-systole
in high heart rates.
The International Journal of Cardiovascular Imaging 04/2012; 25(8):837-845. · 2.29 Impact Factor
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ABSTRACT: To determine whether increasing epinephrine infusion in an in vivo pig model is associated with an increase in end-systolic magnetic resonance elastography (MRE)-derived effective stiffness.
Finite element modeling (FEM) was performed to determine the range of myocardial wall thicknesses that could be used for analysis. Then MRE was performed on five pigs to measure the end-systolic effective stiffness with epinephrine infusion. Epinephrine was continuously infused intravenously in each pig to increase the heart rate in increments of 20%. For each such increase end-systolic effective stiffness was measured using MRE. In each pig, Student's t-test was used to compare effective end-systolic stiffness at baseline and at initial infusion of epinephrine. Least-square linear regression was performed to determine the correlation between normalized end-systolic effective stiffness and increase in heart rate with epinephrine infusion.
FEM showed that phase gradient inversion could be performed on wall thickness ≈≥1.5 cm. In pigs, effective end-systolic stiffness significantly increased from baseline to the first infusion in all pigs (P = 0.047). A linear correlation was found between normalized effective end-systolic stiffness and percent increase in heart rate by epinephrine infusion with R(2) ranging from 0.86-0.99 in four pigs. In one of the pigs the R(2) value was 0.1. A linear correlation with R(2) = 0.58 was found between normalized effective end-systolic stiffness and percent increase in heart rate when pooling data points from all pigs.
Noninvasive MRE-derived end-systolic effective myocardial stiffness may be a surrogate for myocardial contractility.
Journal of Magnetic Resonance Imaging 02/2012; 36(1):120-7. · 2.70 Impact Factor
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ABSTRACT: To demonstrate feasibility of using MR elastography (MRE) to identify hypertensive changes in the abdominal aorta when compared with normotensives based on the stiffness measurements.
MRE was performed on eight volunteers (four normotensives and four hypertensives) to measure the effective stiffness of the abdominal aorta. MRE wave images are directionally filtered and phase gradient analysis was performed to determine the stiffness of the aorta. Student's t-test was performed to determine significant difference in stiffness measurements between normotensives and hypertensives.
The normotensive group demonstrated a mean abdominal aortic stiffness of 3.7 ± 0.8 kPa, while the controlled-hypertensive demonstrated a mean abdominal aortic stiffness of 9.3 ± 1.9 kPa. MRE effective stiffness of abdominal aorta in hypertensives was significantly greater than that of normotensives with p = 0.02.
Feasibility of in vivo aortic MRE is demonstrated. Hypertensives have significantly higher aortic stiffness assessed through MRE than normotensives.
Journal of Magnetic Resonance Imaging 11/2011; 35(3):582-6. · 2.70 Impact Factor
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ABSTRACT: Primary sarcomas of the aorta, pulmonary artery, superior vena cava, inferior vena cava, and the heart are rare neoplasms. Aortic sarcomas are broadly categorized as either primarily luminal or primarily mural, with luminal sarcomas more likely to be misdiagnosed as thrombus. Pulmonary artery sarcomas are often mistaken for pulmonary embolism both clinically and at imaging. Vena caval sarcomas appear as intraluminal or extraluminal masses connecting to or filling the veins. The most common are leiomyosarcomas of the inferior vena cava. Primary sarcomas of the heart are rare and usually appear as heterogeneous aggressive masses.
Seminars in ultrasound, CT, and MR. 10/2011; 32(5):377-404.
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Journal of Nuclear Cardiology 09/2011; 18(6):1111-4. · 2.67 Impact Factor
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ABSTRACT: To describe findings of patients with surgically confirmed pericardial disease on state of the art MR sequences. Retrospective review was performed for patients who underwent pericardiectomy and preoperative MR over a 5 year period ending in 2009. Patients' records were reviewed to confirm the diagnosis of chronic recurrent pericarditis, constrictive pericarditis, or pericardial tumor. MR imaging findings of pericardial thickness, IVC diameter, presence or absence of pericardial or pleural effusion, pericardial edema, pericardial enhancement, and septal "bounce" were recorded. Patients with constriction had a larger IVC diameter (3.1 ± 0.4 cm) than patients with recurrent pain and no constriction (2.0 ± 0.4 cm). Mean pericardial thickness for the 16 patients with chronic recurrent pericarditis but no evidence of constriction was 4.8 ± 2.9 mm. Mean pericardial thickness for patients with constriction was 9.2 ± 7.0 cm with calcification, and 4.6 ± 2.1 cm without calcification. 94% of patients with chronic recurrent pericarditis had gadolinium enhancement of the pericardium, while 76% of patients with constriction had pericardial enhancement. Septal "bounce" was present in 19% of chronic recurrent pericarditis cases and 86% of constriction cases. 5 patients had a pericardial neoplasm, 1 of which was not identified preoperatively. State of the art MR techniques can identify significant and distinct findings in patients with chronic recurrent pericarditis, constrictive pericarditis, and pericardial tumors.
The international journal of cardiovascular imaging 07/2011; 28(5):1099-109. · 2.15 Impact Factor
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ABSTRACT: To compare magnetic resonance elastography (MRE) effective stiffness to end-diastolic pressure at different loading conditions to demonstrate a relationship between myocardial MRE effective stiffness and end-diastolic left ventricular (LV) pressure.
MRE was performed on four pigs to measure the end-diastolic effective stiffness under different loading conditions. End-diastolic pressure was increased by infusing Dextran-40 (20% of blood volume). For each infusion of Dextran-40, end-diastolic pressure was recorded and end-diastolic effective stiffness was measured using MRE. In each pig, least-square linear regression was performed to determine the correlation between end-diastolic effective stiffness and end-diastolic LV pressure.
A linear correlation was found between end-diastolic LV pressure and end-diastolic effective stiffness with R(2) ranging from 0.73-0.9. A linear correlation with R(2) = 0.26 was found between end-diastolic LV pressure and end-diastolic effective stiffness when pooling data points from all pigs.
End-diastolic effective myocardial stiffness increases linearly with end-diastolic LV pressure.
Journal of Magnetic Resonance Imaging 05/2011; 33(5):1224-8. · 2.70 Impact Factor
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Journal of the American College of Cardiology 04/2011; 57(17):1721-34. · 14.16 Impact Factor
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ABSTRACT: In contrast to generalized aneurysmal dilatation of the aortic root, discrete sinus of Valsalva aneurysm is an uncommon condition most often affecting the right coronary sinus. We recently treated a patient without the known connective tissue disorder having discrete aneurysms of all three sinuses.
The Annals of thoracic surgery 02/2011; 91(2):e26-7. · 3.74 Impact Factor
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ABSTRACT: Thoracic aortic aneurysms tend to be asymptomatic and were previously often diagnosed only after a complication such as dissection or rupture occurred. Better imaging techniques and an increase in the use of cross-sectional imaging has led to an increase in the diagnosis of aortic aneurysms, which has allowed for elective treatment prior to the development of a complication. The location, size and etiology of an aneurysm all impact the clinical outcomes and these factors are used to determine the appropriate timing of surgical replacement. Surgeons often rely on the information obtained from preoperative imaging to determine when to intervene and what type of procedure will be necessary, making it important for the radiologist to understand these issues in order to provide the necessary information. Postoperative imaging after surgical replacement of the aorta is also important, as there are some common findings that occur in this patient population that can impact how they are treated. The purpose of this article is to review the etiology and associated findings of aneurysms of the ascending aorta and arch, with a focus on how computed tomography angiography and magnetic resonance angiography findings are used to determine the appropriate timing for elective replacement and the type of surgical procedure, as well as the role of follow-up imaging. This will include a review of the most commonly performed types of surgical procedures, to provide an understanding of how the findings of preoperative imaging studies impact what the surgeon does in the operating room, as well as the expected findings of postoperative imaging studies.
Expert Review of Cardiovascular Therapy 01/2011; 9(1):45-61.
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ABSTRACT: We present a patient with superior vena cava (SVC) obstruction due to multiple intraluminal pacemaker leads. Previous attempts at balloon dilatation of the SVC and surgical angioplasty did not provide a long-term solution. A Gore-Tex (W. L. Gore & Associates, Flagstaff, AZ, USA) conduit interposed between the innominate vein and right atrial appendage has resulted in symptomatic relief at a follow-up of 6 months.
Journal of Cardiac Surgery 10/2010; 25(6):752-5. · 0.87 Impact Factor
