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Dive into the research topics where Kirsten Tolstrup is active.

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Featured researches published by Kirsten Tolstrup.


Journal of the American College of Cardiology | 2009

Aortopathy is Prevalent in Relatives of Bicuspid Aortic Valve Patients

Simon Biner; Asim Rafique; Indraneil Ray; Olivera Cuk; Robert J. Siegel; Kirsten Tolstrup

OBJECTIVES This study aimed to determine the prevalence of dilation and abnormal elastic properties of aortic root in first-degree relatives (FDRs) of bicuspid aortic valve (BAV) patients. BACKGROUND Evidence indicates that BAV is a genetic disorder. Although FDRs of affected individuals have an increased prevalence of BAV, their risk of aortic root abnormalities is unknown. METHODS We studied dimensions as well as the elastic properties of the ascending aorta in 48 FDRs with morphologically normal tricuspid aortic valves, 54 BAV patients, and 45 control subjects using 2-dimensional echocardiography. RESULTS The prevalence of aortic root dilation was 32% in FDRs and 53% in BAV patients, whereas all control subjects showed normal aortic dimensions (p < 0.001). The FDRs and BAVs had significantly lower aortic distensibility (1.7 +/- 1.4 x 10(-3) mm Hg and 1.4 +/- 2.0 x 10(-3) mm Hg vs. 2.5 +/- 1.6 x 10(-3) mm Hg, p < 0.001) and greater aortic stiffness index (26.7 +/- 25.8 and 55.9 +/- 76.8 vs. 18.7 +/- 40.1, p = 0.001) compared with control subjects. This difference remained significant in subjects without aortic root dilation or hypertension (p = 0.002 and p = 0.004, respectively). CONCLUSIONS The aortic root is functionally abnormal and dilation is common (32%) in first-degree relatives of patients with BAV. Screening of FDRs by transthoracic 2-dimensional echocardiography should be considered for detection of aortic valve malformation and dilated ascending aorta.


Jacc-cardiovascular Imaging | 2010

Reproducibility of Proximal Isovelocity Surface Area, Vena Contracta, and Regurgitant Jet Area for Assessment of Mitral Regurgitation Severity

Simon Biner; Asim Rafique; Farhad Rafii; Kirsten Tolstrup; Omid Noorani; Takahiro Shiota; Swaminatha V. Gurudevan; Robert J. Siegel

OBJECTIVES The aim of this study was to evaluate the interobserver agreement of proximal isovelocity surface area (PISA) and vena contracta (VC) for differentiating severe from nonsevere mitral regurgitation (MR). BACKGROUND Recommendation for MR evaluation stresses the importance of VC width and effective regurgitant orifice area by PISA measurements. Reliable and accurate assessment of MR is important for clinical decision making regarding corrective surgery. We hypothesize that color Doppler-based quantitative measurements for classifying MR as severe versus nonsevere may be particularly susceptible to interobserver agreement. METHODS The PISA and VC measurements of 16 patients with MR were interpreted by 18 echocardiologists from 11 academic institutions. In addition, we obtained quantitative assessment of MR based on color flow Doppler jet area. RESULTS The overall interobserver agreement for grading MR as severe or nonsevere using qualitative and quantitative parameters was similar and suboptimal: 0.32 (95% confidence interval [CI]: 0.1 to 0.52) for jet area-based MR grade, 0.28 (95% CI: 0.11 to 0.45) for VC measurements, and 0.37 (95% CI: 0.16 to 0.58) for PISA measurements. Significant univariate predictors of substantial interobserver agreement for: 1) jet area-based MR grade was functional etiology (p = 0.039); 2) VC was central MR (p = 0.013) and identifiable effective regurgitant orifice (p = 0.049); and 3) PISA was presence of a central MR jet (p = 0.003), fixed proximal flow convergence (p = 0.025), and functional etiology (p = 0.049). Significant multivariate predictors of raw interobserver agreement > or =80% included: 1) for VC, identifiable effective regurgitant orifice (p = 0.035); and 2) for PISA, central regurgitant jet (p = 0.02). CONCLUSIONS The VC and PISA measurements for distinction of severe versus nonsevere MR are only modestly reliable and associated with suboptimal interobserver agreement. The presence of an identifiable effective regurgitant orifice improves reproducibility of VC and a central regurgitant jet predicts substantial agreement among multiple observers of PISA assessment.


Heart | 2007

Assessment of aortic stenosis by three-dimensional echocardiography: an accurate and novel approach

Sorel Goland; Alfredo Trento; Kiyoshi Iida; Lawrence S.C. Czer; Michele A. De Robertis; Tasneem Z. Naqvi; Kirsten Tolstrup; Takashi Akima; Huai Luo; Robert J. Siegel

Background: Accurate assessment of aortic valve area (AVA) is important for clinical decision-making in patients with aortic valve stenosis (AS). The role of three-dimensional echocardiography (3D) in the quantitative assessment of AS has not been evaluated so far. Objectives: To evaluate the reproducibility and accuracy of real-time three-dimensional echocardiography (RT3D) and 3D-guided two-dimensional planimetry (3D/2D) for assessment of AS, and compare these results with those of standard echocardiography and cardiac catheterisation (Cath). Methods: AVA was estimated by transthoracic echo-Doppler (TTE) and by direct planimetry using transoesophageal echocardiography (TEE) as well as RT3D and 3D/2D. 15 patients underwent assessment of AS by Cath. Results: 33 patients with AS were studied (20 men, mean (SD) age 70 (14) years). Bland–Altman analysis showed good agreement and small absolute differences in AVA between all planimetric methods (RT3D vs 3D/2D: −0.01 (0.15) cm2; 3D/2D vs TEE: 0.05 (0.22) cm2; RT3D vs TEE: 0.06 (0.26) cm2). The agreement between AVA assessment by 2D–TTE and planimetry was −0.01 (0.20) cm2 for 3D/2D; 0.00 (0.15) cm2 for RT3D; and −0.05 (0.30) cm2 for TEE. Correlation coefficient r for AVA assessment between each of 3D/2D, RT3D, TEE planimetry and Cath was 0.81, 0.86 and 0.71, respectively. The intraobserver variability was similar for all methods, but interobserver variability was better for 3D techniques than for TEE (p<0.05). Conclusions: The 3D echo methods for planimetry of the AVA showed good agreement with the standard TEE technique and flow-derived methods. Compared with AV planimetry by TEE, both 3D methods were at least as good as TEE and had better reproducibility. 3D aortic valve planimetry is a novel non-invasive technique, which provides an accurate and reliable quantitative assessment of AS.


American Journal of Cardiology | 2012

Comparison of Left Ventricular Outflow Geometry and Aortic Valve Area in Patients With Aortic Stenosis by 2-Dimensional Versus 3-Dimensional Echocardiography

Takeji Saitoh; Maiko Shiota; Masaki Izumo; Swaminatha V. Gurudevan; Kirsten Tolstrup; Robert J. Siegel; Takahiro Shiota

The present study sought to elucidate the geometry of the left ventricular outflow tract (LVOT) in patients with aortic stenosis and its effect on the accuracy of the continuity equation-based aortic valve area (AVA) estimation. Real-time 3-dimensional transesophageal echocardiography (RT3D-TEE) provides high-resolution images of LVOT in patients with aortic stenosis. Thus, AVA is derived reliably with the continuity equation. Forty patients with aortic stenosis who underwent 2-dimensional transthoracic echocardiography (2D-TTE), 2-dimensional transesophageal echocardiography (2D-TEE), and RT3D-TEE were studied. In 2D-TTE and 2D-TEE, the LVOT areas were calculated as π × (LVOT dimension/2)(2). In RT3D-TEE, the LVOT areas and ellipticity ([diameter of the anteroposterior axis]/[diameter of the medial-lateral axis]) were evaluated by planimetry. The AVA is then determined using planimetry and the continuity equation method. LVOT shape was found to be elliptical (ellipticity of 0.80 ± 0.08). Accordingly, the LVOT areas measured by 2D-TTE (median 3.7 cm(2), interquartile range 3.1 to 4.1) and 2D-TEE (median 3.7 cm(2), interquartile range 3.1 to 4.0) were smaller than those by 3D-TEE (median 4.6 cm(2), interquartile range 3.9 to 5.3; p <0.05 vs both 2D-TTE and 2D-TEE). RT3D-TEE yielded a larger continuity equation-based AVA (median 1.0 cm(2), interquartile range 0.79 to 1.3, p <0.05 vs both 2D-TTE and 2D-TEE) than 2D-TTE (median 0.77 cm(2), interquartile range 0.64 to 0.94) and 2D-TEE (median 0.76 cm(2), interquartile range 0.62 to 0.95). Additionally, the continuity equation-based AVA by RT3D-TEE was consistent with the planimetry method. In conclusion, RT3D-TEE might allow more accurate evaluation of the elliptical LVOT geometry and continuity equation-based AVA in patients with aortic stenosis than 2D-TTE and 2D-TEE.


Journal of The American Society of Echocardiography | 2016

Guidelines for the Use of Echocardiography in the Evaluation of a Cardiac Source of Embolism

Muhamed Saric; Alicia Armour; M. Samir Arnaout; Farooq A. Chaudhry; Richard A. Grimm; Itzhak Kronzon; Bruce F. Landeck; Kameswari Maganti; Hector I. Michelena; Kirsten Tolstrup

Embolism from the heart or the thoracic aorta often leads to clinically significant morbidity and mortality due to transient ischemic attack, stroke or occlusion of peripheral arteries. Transthoracic and transesophageal echocardiography are the key diagnostic modalities for evaluation, diagnosis, and management of stroke, systemic and pulmonary embolism. This document provides comprehensive American Society of Echocardiography guidelines on the use of echocardiography for evaluation of cardiac sources of embolism. It describes general mechanisms of stroke and systemic embolism; the specific role of cardiac and aortic sources in stroke, and systemic and pulmonary embolism; the role of echocardiography in evaluation, diagnosis, and management of cardiac and aortic sources of emboli including the incremental value of contrast and 3D echocardiography; and a brief description of alternative imaging techniques and their role in the evaluation of cardiac sources of emboli. Specific guidelines are provided for each category of embolic sources including the left atrium and left atrial appendage, left ventricle, heart valves, cardiac tumors, and thoracic aorta. In addition, there are recommendation regarding pulmonary embolism, and embolism related to cardiovascular surgery and percutaneous procedures. The guidelines also include a dedicated section on cardiac sources of embolism in pediatric populations.


American Journal of Cardiology | 2002

Aortic valve sclerosis, mitral annular calcium, and aortic root sclerosis as markers of atherosclerosis in men

Kirsten Tolstrup; Carlos A. Roldan; Clifford Qualls; Michael H. Crawford

Aortic valve sclerosis (AVS) and mitral annular calcium (MAC) as detected by transthoracic echocardiography have been associated with atherosclerosis. Aortic root sclerosis (ARS) may have a similar association, but has not been studied. This study evaluates, by transesophageal echocardiography, the association of AVS, MAC, and ARS with aortic atheromatous disease and cardiovascular disease. Multiplane transesophageal echocardiography with evaluation of AVS, MAC, ARS, and aortic atheromatous disease by 2 experienced observers unaware of clinical data was performed in 157 male patients > or =50 years old. The presence of cardiovascular disease, defined as coronary, carotid, or peripheral artery disease, was determined by specific criteria. The prevalence of AVS, MAC, ARS, and aortic atheromatous disease was 42%, 30%, 48%, and 71%, respectively. The presence of AVS, MAC, or ARS was highly associated with aortic atheromatous disease (odds ratio 4.9 to 12.0, confidence interval 1.4 to 35.8, p <0.001). ARS was also associated with cardiovascular disease (odds ratio 2.2, confidence interval 1.0 to 4.5, p = 0.038). The presence of AVS, MAC, or ARS had a sensitivity of 77%, specificity of 72%, a positive predictive value of 88%, and a negative predictive value of 55% for aortic atheromatous disease. We concluded that the prevalence of AVS, MAC, or ARS by transesophageal echocardiography in men is common, and their presence is highly associated with aortic atheromatous disease and coronary, carotid, or peripheral artery disease.


The Cardiology | 2006

Non-invasive resting magnetocardiographic imaging for the rapid detection of ischemia in subjects presenting with chest pain

Kirsten Tolstrup; Bo E. Madsen; Jose A. Ruiz; Stephen D. Greenwood; Judeen Camacho; Robert J. Siegel; H. Caroline Gertzen; Jai-Wun Park; Peter A. Smars

Background: Early diagnosis of ischemia is complicated by the poor sensitivity of standard tests and contraindication for stress testing in unstable angina patients. Magnetocardiography (MCG) imaging can be used for the rapid, non-invasive detection of ischemia at rest. Methods: We studied 125 patients with presumed ischemic chest pain. All were chest pain free at the time of scanning. A 6-minute resting MCG scan (CardioMag Imaging, Inc., New York, 9-channel system) was performed. Following the MCG scan, automated software data analysis was performed, and quantitative scores were automatically calculated for each subject. The presence of ischemia was determined after testing with serial troponins, stress testing, and/or coronary angiography. Results: The mean age was 59.4 ± 13.6 years. Most patients (86.4%) had non-ischemic 12-lead ECG and normal troponin (86.2%). Fifty-five patients (44.0%) were determined to be ischemic. The MCG sensitivity, specificity, positive and negative predictive value was 76.4, 74.3, 70.0 and 80.0%, respectively, for the detection of ischemia (p < 0.0001). Conclusions: MCG is a new rapid, non-invasive imaging tool able to detect repolarization abnormalities at rest consistent with ischemia in patients presenting with chest pain syndrome and normal or non-specific 12-lead ECG and normal troponin.


Jacc-cardiovascular Imaging | 2010

Septal thrombus in the left atrium: is the left atrial septal pouch the culprit?

Swaminatha V. Gurudevan; Hetan Shah; Kirsten Tolstrup; Robert J. Siegel; Subramaniam C. Krishnan

cardioembolic strokes are responsible for more than 20% of all ischemic strokes. The examination of atrial sources of cardioembolic strokes has focused almost exclusively on the left atrial appendage (LAA) and the pathophysiology of thrombus formation at this site is well understood. However,


American Journal of Cardiology | 2012

Echocardiographic Evaluation of Iatrogenic Atrial Septal Defect After Catheter-Based Mitral Valve Clip Insertion

Takeji Saitoh; Masaki Izumo; Azusa Furugen; Jun Tanaka; Yoko Miyata-Fukuoka; Swaminatha V. Gurudevan; Kirsten Tolstrup; Robert J. Siegel; Saibal Kar; Takahiro Shiota

The geometries and sizes of persistent iatrogenic atrial septal defects (IASDs) after transseptal puncture during catheter-based mitral valve clip insertion (MVCI) have not been detailed. In this study, 11 IASDs were investigated in 10 patients who underwent MVCI using a guide catheter (24Fr proximally and 22Fr at the atrial septum). The diameters of the long and short axes and the area at maximum and minimum during a cardiac cycle were measured after MVCI using real-time 3-dimensional (RT3D) transesophageal echocardiography (TEE). A circular shape was assumed on 2-dimensional TEE, resulting in an area calculation of π × (dimension/2)(2). The anatomic geometries of IASDs were visualized in a 3-dimensional en face view of the atrial septum. Furthermore, 1 month after MVCI, IASDs were evaluated using echocardiography. The IASDs had a variety of irregular geometries. The mean long-axis diameter was 1.0 ± 0.24 cm, the mean short-axis diameter was 0.51 ± 0.22 cm, and the mean area was 0.40 ± 0.24 cm(2) on RT3D TEE. The diameters and area changed significantly between the maximal and minimal values during the cardiac cycle. Importantly, 2-dimensional TEE underestimated the maximal diameters of IASDs (0.54 ± 0.17 vs 1.0 ± 0.24 cm by RT3D TEE, p <0.01) and the maximal areas of IASDs (0.25 ± 0.15 vs 0.40 ± 0.23 cm(2) by RT3D TEE, p <0.05). One month after MVCI, the smallest and the second smallest IASDs had closed, and the other 9 remained open. In conclusion, RT3D TEE is useful to assess the irregular geometries of IASDs created during MVCI.


American Journal of Cardiology | 2011

Utility of three-dimensional transesophageal echocardiography in the diagnosis of valvular perforations.

Keith A. Thompson; Takahiro Shiota; Kirsten Tolstrup; Swaminatha V. Gurudevan; Robert J. Siegel

Three-dimensional (3D) transesophageal echocardiographic (TEE) imaging is a relatively new imaging modality that is increasingly being used to characterize a variety of cardiac pathologic features. In the present study, we reviewed the 2-dimensional (2D) and 3D TEE images from our echocardiographic database to identify patients with valve perforations. A review of the 2D TEE images resulted in the identification of 11 valvular perforations (6 aortic valves, 4 mitral valves, and 1 tricuspid valve). A review of the 3D TEE images allowed for the identification of 15 valve perforations (7 aortic valves, 7 mitral valves, and 1 tricuspid valve), including 4 perforations that could not be diagnosed using 2D imaging alone. In conclusion, 3D TEE imaging provided added benefit to traditional 2D TEE imaging because of its ability to provide en face visualization of the cardiac valves, allowing improved identification and precise anatomic localization of the perforation.

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Robert J. Siegel

Cedars-Sinai Medical Center

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Takahiro Shiota

Cedars-Sinai Medical Center

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Masaki Izumo

St. Marianna University School of Medicine

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Yoko Fukuoka

Cedars-Sinai Medical Center

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Asim Rafique

Cedars-Sinai Medical Center

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Jun Tanaka

Cedars-Sinai Medical Center

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Huai Luo

Cedars-Sinai Medical Center

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Yoram Neuman

Cedars-Sinai Medical Center

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