Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 6 de 6
Filter
1.
Methodist Debakey Cardiovasc J ; 19(1): 32-37, 2023.
Article in English | MEDLINE | ID: mdl-37064497

ABSTRACT

A 62-year-old male presented to the emergency department with acute viral bronchitis and worsening of his chronic dyspnea on exertion. Incidentally, a murmur was detected on physical examination. Extensive work-up, including coronary computed tomography angiography, revealed a rare combination and potential association between severe bicuspid aortic valve stenosis and coronary-pulmonary artery fistulas.


Subject(s)
Aortic Valve Stenosis , Bicuspid Aortic Valve Disease , Coronary Artery Disease , Fistula , Heart Defects, Congenital , Male , Humans , Middle Aged , Pulmonary Artery/diagnostic imaging , Constriction, Pathologic , Aortic Valve Stenosis/complications , Aortic Valve Stenosis/diagnostic imaging , Aortic Valve/diagnostic imaging , Aortic Valve/surgery
2.
J Appl Clin Med Phys ; 20(9): 12-19, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31282083

ABSTRACT

PURPOSE: Increased use of Linac-based stereotactic radiosurgery (SRS), which requires highly noncoplanar gantry trajectories, necessitates the development of efficient and accurate methods of collision detection during the treatment planning process. This work outlines the development and clinical implementation of a patient-specific computed tomography (CT) contour-based solution that utilizes Eclipse Scripting to ensure maximum integration with clinical workflow. METHODS: The collision detection application uses triangle mesh structures of the gantry and couch, in addition to the body contour of the patient taken during CT simulation, to virtually simulate patient treatments. Collision detection is performed using Binary Tree Hierarchy detection methods. Algorithm accuracy was first validated for simple cuboidal geometry using a calibration phantom and then extended to an anthropomorphic phantom simulation by comparing the measured minimum distance between structures to the predicted minimum distance for all allowable orientations. The collision space was tested at couch angles every 15° from 90 to 270 with the gantry incremented by 5° through the maximum trajectory. Receiver operating characteristic curve analysis was used to assess algorithm sensitivity and accuracy for predicting collision events. Following extensive validation, the application was implemented clinically for all SRS patients. RESULTS: The application was able to predict minimum distances between structures to within 3 cm. A safety margin of 1.5 cm was sufficient to achieve 100% sensitivity for all test cases. Accuracy obtained was 94.2% with the 5 cm clinical safety margin with 100% true positive collision detection. A total of 88 noncoplanar SRS patients have been currently tested using the application with one collision detected and no undetected collisions occurring. The average time for collision testing per patient was 2 min 58 s. CONCLUSIONS: A collision detection application utilizing patient CT contours was developed and successfully clinically implemented. This application allows collisions to be detected early during the planning process, avoiding patient delays and unnecessary resource utilization if detected during delivery.


Subject(s)
Medical Errors/prevention & control , Neoplasms/surgery , Phantoms, Imaging , Radiosurgery/instrumentation , Radiosurgery/methods , Radiotherapy Planning, Computer-Assisted/methods , Software , Algorithms , Humans , Patient Positioning , Pattern Recognition, Automated , Radiotherapy Dosage , Radiotherapy, Intensity-Modulated/methods
3.
Echocardiography ; 24(7): 739-44, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17651103

ABSTRACT

BACKGROUND: Patients with left ventricular (LV) systolic dysfunction due to coronary artery disease (CAD) may develop stress-induced wall motion abnormalities (SWMA) with low-dose (10 microg/kg/min) dobutamine infusion. The clinical significance of low-dose SWMA is unknown. OBJECTIVE: We investigated the clinical, hemodynamic and angiographic correlates of low-dose SWMA in patients with chronic ischemic LV systolic dysfunction. METHODS: Seventy patients with chronic ischemic LV systolic dysfunction who had dobutamine stress echocardiography were studied. Clinical, hemodynamic, and angiographic parameters at rest and low-dose were compared between 38 patients (mean ejection fraction (EF) of 30 +/- 8%) with low-dose SWMA and 32 patients (EF 30 +/- 11%) without low-dose SWMA. RESULTS: Multivariate analysis showed that the number of coronary territories with severe disease (stenosis > or =70%)(P = 0.001, RR = 6.3) was an independent predictor of low-dose SWMA. An increasing number of collateral vessels protected patients from low-dose SWMA (P = 0.011, RR = 0.25). A higher resting heart rate was a negative predictor of low-dose SWMA (P = 0.015, RR = 0.92) but no other hemodynamic variables were predictors. In the patients with low-dose SMA, regions with low-dose SWMA were more likely to be supplied by vessels with severe disease than regions without low-dose SWMA (92% vs 58%, P < 0.001). CONCLUSION: In patients with ischemic LV systolic dysfunction, the extent of severe disease and a lower numbers of collaterals predict the occurrence of low-dose SWMA. Low-dose SWMA is a highly specific marker for severe disease.


Subject(s)
Dobutamine/adverse effects , Myocardial Ischemia/chemically induced , Myocardial Ischemia/diagnostic imaging , Ventricular Dysfunction, Left/chemically induced , Ventricular Dysfunction, Left/diagnostic imaging , Cardiotonic Agents/adverse effects , Echocardiography/methods , Female , Humans , Infusions, Intravenous , Male , Middle Aged
4.
Am J Cardiol ; 95(8): 1011-4, 2005 Apr 15.
Article in English | MEDLINE | ID: mdl-15820180

ABSTRACT

Tissue Doppler imaging (TDI) patterns from the left atrial appendage (LAA) were evaluated by transesophageal echocardiography. Reproducible, characteristic triphasic or biphasic tissue velocities similar to Doppler flow of the LAA were obtained. Patient peak TDI velocities correlated well with flow and were measurable in atrial fibrillation. Patients with an embolic cerebrovascular accident and in sinus rhythm had higher tissue TDI velocities from the LAA compared with patients without an event, and the groups had similar flow velocities. Hence, Doppler tissue contraction dynamics determined by TDI may complement flow velocities in evaluating LAA function for risk assessment of thromboembolism.


Subject(s)
Atrial Appendage/diagnostic imaging , Atrial Appendage/pathology , Echocardiography, Doppler/methods , Echocardiography, Transesophageal/methods , Thromboembolism/diagnostic imaging , Adult , Aged , Atrial Fibrillation , Female , Humans , Male , Middle Aged , Regional Blood Flow , Risk Assessment , Stroke , Thromboembolism/complications
5.
Am J Cardiol ; 89(7): 811-6, 2002 Apr 01.
Article in English | MEDLINE | ID: mdl-11909564

ABSTRACT

This study examined the value of wall motion scores at rest and with low- and high-dose dobutamine infusion for prediction of outcome and benefit from revascularization in patients with ischemic cardiomyopathy. Follow-up was obtained in 139 patients with ischemic cardiomyopathy who had echocardiography at rest, and during low- (10 microg/kg/min) and high-dose dobutamine (maximal dose 50 microg/kg/min) infusion. Both rest and low-dose wall motion scores were multivariate predictors of cardiac death, but ischemia and peak dose scores were not predictors. Rest scores risk stratified patients into 3 groups: score (1.00 to 1.99) with 11% cardiac death; score (2.00 to 2.49) with 30% death; and score > or =2.50 with 47% death. One third of patients with rest scores > or =2.50 had improvement in scores to < 2.50 with low-dose dobutamine. Their frequency of cardiac death was reduced to 23% compared with 60% (p = 0.04) in those who remained with low-dose scores > or =2.50. Low-dose scores also identified those who benefited from revascularization. In patients with low-dose scores (1.00 to 1.99), the frequency of cardiac death was marginally lower in revascularized than nonrevascularized patients (10% vs 21%, p = 0.28). In patients with scores (2.00 to 2.49), revascularized patients had a significantly lower frequency of cardiac death than nonrevascularized patients (15% vs 41%, p < 0.05). The frequency of death in those with low-dose scores > or =2.50 was very high in both revascularized (75%) and nonrevascularized (56%, p = 0.42) patients. Thus, rest and low-dose wall motion scores enable risk stratification of patients with ischemic cardiomyopathy and identify those who do and do not benefit from revascularization.


Subject(s)
Adrenergic beta-Agonists , Dobutamine , Myocardial Ischemia/diagnosis , Myocardial Ischemia/therapy , Myocardial Revascularization , Rest , Adrenergic beta-Agonists/administration & dosage , Aged , Dobutamine/administration & dosage , Dose-Response Relationship, Drug , Echocardiography , Female , Follow-Up Studies , Humans , Male , Middle Aged , Myocardial Ischemia/diagnostic imaging , Myocardial Ischemia/mortality , Predictive Value of Tests , Prognosis , Proportional Hazards Models , Research Design , Risk , Survival Rate
6.
J Perinatol ; 22(1): 89-90, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11840251

ABSTRACT

We report a patient with fetal hydantoin syndrome (FHS) with associated d-transposition of the great arteries (d-TGA) and persistent hypocalcemia. d-TGA and hypocalcemia have each been individually reported once in association with FHS, but these patients were also prenatally exposed to phenobarbital. To our knowledge, this is the first report of these problems occurring after prenatal exposure to hydantoin alone. The combination of congenital heart disease and hypocalcemia in our patient raises the possibility of a hydantoin effect on neural crest migration.


Subject(s)
Abnormalities, Drug-Induced , Hydantoins/adverse effects , Hypocalcemia/chemically induced , Maternal-Fetal Exchange , Transposition of Great Vessels/chemically induced , Adult , Female , Fetus/drug effects , Humans , Infant, Newborn , Male , Pregnancy , Syndrome
SELECTION OF CITATIONS
SEARCH DETAIL
...