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Navin C Nanda

Publications and source records attributed to Navin C Nanda.

At least 37 records · Page 2Linked to original sources
PubMed2005

Live three-dimensional transthoracic echocardiographic assessment of left atrial tumors.

This preliminary study demonstrates the superiority of live three-dimensional transthoracic echocardiography (3D TTE) over two-dimensional (2D) TTE in the assessment of left atrial (LA) tumors in four patients studied by us (three myxomas, one hemangioma, all subsequently pathologically proven). Because of the unique ability of live 3D TTE to systematically section and view the contents of an intracardiac mass, LA myxomas in the three patients studied could be more confidently diagnosed by noting isolated echolucent areas consistent with hemorrhage/necrosis in the tumor mass. On the other hand, a definite echolucent area was found by 2D TTE in only two of the three patients with myxoma. In the fourth patient with a hemangioma, live 3D TTE showed much more extensive and closely packed echolucencies with little solid tissue as compared to a myxoma consistent with a highly vascularized tumor. In contrast, 2D TTE demonstrated only two isolated echolucencies in the tumor suggesting an erroneous diagnosis of myxoma.

Echocardiography↗
PubMed2005

Transesophageal echocardiographic diagnosis of aortic arch-left innominate vein fistula.

We present a patient with aortic arch-left innominate vein (LIV) fistula diagnosed by transesophageal echocardiography. Also, an interrupted linear echo was noted within the dilated LIV with flow signals moving across the area of interruption, suggestive of left innominate vein pseudo-aneurysm or dissection. The patient subsequently underwent successful surgical repair of the fistula.

Adult↗
PubMed2005

Live three-dimensional transthoracic echocardiographic demonstration of septal perforator coronary artery-left ventricle fistulas following myectomy.

We present an adult patient with hypertrophic cardiomyopathy status post septal myectomy in whom live three-dimensional transthoracic echocardiography (3D TTE) demonstrated two septal perforator coronary arteries opening directly into the left-ventricular outflow tract. Only one of these fistulas could be demonstrated by two-dimensional transthoracic echocardiography (2D TTE). Our case demonstrates the potential usefulness of 3D TTE as a supplement to 2D TTE in the assessment of septal coronary artery-left ventricle fistulas.

Cardiomyopathy, Hypertrophic↗
PubMed2005

Can transthoracic echocardiography with subcostal view predict abdominal aortic atherosclerosis?

BACKGROUND: Prompt detection of atherosclerosis (ATH) may profoundly impact therapy and patient outcome. During transthoracic echocardiography (TTE), subcostal views may suggest abdominal (ABD) aortic (AO) ATH, but this diagnosis may be inaccurate due to suboptimal images, which may in part relate to use of nonlinear probes. Therefore, we investigated the accuracy of TTE assessment of ABD AO ATH relative to transesophageal (TEE) AO images. METHODS: Routine clinical TTE and TEE studies of 100 patients (44 men), aged 30-92 years old, were reviewed retrospectively and blindly. ABD AO ATH by TTE was graded qualitatively as grade (GR) 0 = smooth wall surface; GR 1, 2, and 3 = mild, moderate, and severe irregularities, respectively; and GR 4 = mobile/complex plaque. TEE images were graded quantitatively as the maximal intimal-medial, or plaque thickness, imaged in the AO arch or descending AO, as: GR 0 4 mm, or GR 4 = mobile/complex plaque >4 mm. TTE ability to detect the presence (>GR 0) of ABD AO ATH on TEE was measured in terms of sensitivity (SN), specificity (SP), positive (PPV) and negative (NPV) predictive accuracy-in patients with adequate and suboptimal images-compared to TEE. RESULTS: TTE image quality was adequate in 75 patients and suboptimal in 25. SP and PPV of grading ATH by TTE were directly related to grading by TEE; however, SN and NPV demonstrated an inverse relationship with increasing grading of ATH. TTE correlated with TEE grading with an r = 0.42 (P = 0.0001) for patients (n = 75) with adequate TTE and r = 0.32 (P = 0.001) for all patients (n = 100), including those with suboptimal TTE images. CONCLUSION: Routine TTE imaging is usually correct in predicting ATH on TEE, but with modest error, it should generally not be relied on as a definitive test for ATH. Adequate image quality improves the correlation of TEE and TTE grading of ABD ATH, and more severe ATH on TTE is more predictive of ATH on TEE.

Adult↗
PubMed2005

Transthoracic and transesophageal echocardiographic assessment of mitral regurgitation severity: usefulness of qualitative and semiquantitative techniques.

In this report, we review the advantages, limitations, and optimal utilization of various transthoracic and transesophageal echocardiographic (TTE and TEE) methods used for assessing mitral regurgitation (MR) as published in full-length, peer-reviewed articles since the color Doppler era began in 1984. In addition, comparison is made to other imaging modalities including catheter-based, magnetic resonance and surgical assessment of MR. Although left ventricular (LV) angiography has been traditionally used for validation of various TTE methods and is time-honored, its considerable limitations preclude it from being a real "gold standard." Based on the reviewed literature, no clear "gold standard" for the assessment of MR can be identified at present, but newly emerging TTE and TEE techniques, such as three-dimensional color Doppler, may have the potential to overcome some of the limitations of the two-dimensional methods.

Cardiac Catheterization↗
PubMed2005

Assessment of aortic regurgitation by live three-dimensional transthoracic echocardiographic measurements of vena contracta area: usefulness and validation.

In this report, we evaluate 56 consecutive adult patients who underwent standard two-dimensional (2D) and live three-dimensional transthoracic echocardiography (3D TTE), as well as left heart catheterization with aortography (45 patients) or cardiac surgery (11 patients), for evaluation of aortic insufficiency. Similar to the method we previously described for mitral insufficiency, aortic regurgitant vena contracta area (VCA) was obtained by 3D TTE by systematic and sequential cropping of the acquired 3D TTE data set. Assessments of aortic regurgitation (AR) by aortography and surgery are compared to measurements of VCA by 3D TTE and to 2D TTE measurements of vena contracta width (VCW). Aortographic or surgical grading correlated well with 2D TTE measurements of VCW (r = 0.92), but correlated better with 3D TTE measurements of VCA (r = 0.95), with improved dispersion between angiographic grades demonstrated by the 3D TTE technique. Live 3D TTE color Doppler measurements of VCA can be used for accurate assessment of AR and are comparable to assessment by aortography.

Adult↗
PubMed2005

Effect of cardiac resynchronization therapy on longitudinal and circumferential left ventricular mechanics by velocity vector imaging: description and initial clinical application of a novel method using high-frame rate B-mode echocardiographic images.

Cardiac resynchronization therapy (CRT) has emerged as an important method to treat patient with symptomatic heart failure with evidence of intraventricular dyssynchrony. Tissue Doppler imaging by echocardiography has been shown to be an excellent tool for the assessment of mechanical left ventricular dyssynchrony and the selection of patients for CRT. However, there are some patients who do not show symptomatic improvement following CRT. One possible explanation for this is the need to optimize not only longitudinal synchrony, but also improve the circumferential and radial dynamics of the left ventricle. Doppler imaging does not allow reliable assessment of the latter because of the angle-dependency of the technique. Velocity Vector Imaging (VVI) is a newer technique which is angle-independent and thus provides an avenue to evaluate short-axis mechanics of the left ventricle. We describe a case in which VVI was used to assess the left ventricular dynamics in a patient with heart failure who did not respond to CRT.

Algorithms↗
PubMed2005

Live/real time three-dimensional transthoracic echocardiographic assessment of Ebstein's anomaly.

We describe our experience in using live/real time three-dimensional transthoracic echocardiography (3D TTE) in the assessment of five adult patients with Ebstein's anomaly. The technique was found useful in assessing the distribution and extent of tethering of each of the three leaflets of the tricuspid valve (TV) to the underlying right ventricular walls and the ventricular septum. The characteristic bubble-like appearance resulting from bulging of the non-tethered areas of the TV leaflets was also well visualized in three dimensions and their size measured. Thus, an estimate of the nontethered or free segments of all three leaflets of the TV could be obtained using this technique. This has important implications when considering these patients for surgical repair of the TV. Visualization of all three leaflets of the TV and their extent of tethering by 3D TTE also made it easier to identify the boundaries of the functioning right ventricular chamber potentially providing a more reliable assessment of its volumes and ejection fraction. Cropping of color Doppler 3D TTE data sets provided en face viewing of the TV regurgitation vena contracta permitting accurate assessment of its shape and size. This has the potential to provide a more accurate quantitative estimation of TV regurgitation severity as compared to two-dimensional color Doppler. In conclusion, live/real time 3D TTE appears useful in supplementing two-dimensional echocardiography in more comprehensively assessing the morphologic features of Ebstein's anomaly.

Adolescent↗
PubMed2005

Live three-dimensional transthoracic echocardiographic assessment of ventricular noncompaction.

We present eight adult patients with noncompaction (four with isolated left ventricular noncompaction and four with combined left and right ventricular noncompaction) in whom live three-dimensional transthoracic echocardiography (3D TTE) demonstrated multiple, prominent myocardial trabeculations, deep intertrabecular recesses communicating with the ventricular cavity, and a typical honeycombing appearance. In the four patients with combined right and left ventricular noncompaction, very extensive trabeculations in the right ventricle were identified, much more than in normal or hypertrophied right ventricles. Five of the eight patients were not definitively identified to have noncompaction on two-dimensional (2D) TTE, but the diagnosis was made with 3D TTE. These cases demonstrate the potential usefulness of 3D TTE as a supplement to 2D TTE in the assessment of noncompaction.

Adult↗
PubMed2005

Transesophageal two-dimensional echocardiographic identification of hiatal hernia.

We report a case of a middle-aged woman in whom a transesophageal echocardiogram showed a mass-like lesion posteriorly near the descending thoracic aorta. We were able to make a definitive diagnosis of this mass as a hiatal hernia because of a thick inner lining measuring 6-9 mm in thickness similar to the stomach mucosa, and the presence of a few microbubbles within the mass. In addition, the microbubbles increased considerably after 10 cc of agitated normal saline flush via a nasogastric tube.

Adult↗
PubMed2004

Prevalence of diabetes mellitus and related conditions in Asian Indians living in the United States.

This study is the first attempt to evaluate the prevalence of diabetes mellitus and related conditions in Asian Indians living in the United States. A community-based survey of 1,046 Asian Indian immigrants living in and around the Atlanta metro area of Georgia was conducted and found an overall prevalence of diabetes mellitus of 18.3% (22.5% in men and 13.6% in women). This prevalence of diabetes mellitus in Asian Indians is much higher than in whites, blacks, and Hispanics living in the United States.

Adolescent↗
PubMed2004

Prevalence of stroke and associated risk factors in Asian Indians living in the state of Georgia, United States of America.

This study is the first attempt to assess the prevalence of stroke and associated risk factors in Asian Indians living in the United States. The overall prevalence of stroke is 2.77% (men 3.72% and women 1.77%). Stroke was significantly associated with systemic hypertension, diabetes mellitus, coronary artery disease, end-stage renal disease, and family history of stroke and myocardial infarction.

Coronary Disease↗
PubMed2004

Contrast echocardiography: new agents.

In this report, we review the history, rationale, current status and future directions of contrast agents in echocardiography. First, we discuss the historic development of contrast agents through a review of important physical principles of microbubbles in ultrasonography. Second, we identify attributes of an ideal contrast agent and review those that are currently available or in the "pipeline" for clinical use. Third, we review indications for contrast echocardiography, including endocardial border detection, perfusion quantification and reperfusion assessment, and validate these observations by comparisons with other imaging modalities. Then, we briefly review different methodologies of performing a contrast study, including interrupted, real-time and a hybrid modality. Finally, we identify novel future applications of the newest contrast agents. These newer concepts in contrast echocardiography should form a foundation for nearly limitless application of echocardiography in improved anatomical assessment, perfusion imaging and even special applications, such as detection of vascular inflammation and site-specific drug delivery.

Contrast Media↗
PubMed2004

Mitral prosthetic inflow mimicking severe aortic regurgitation.

We describe two patients in whom mitral valve prosthetic inflow mimicked severe aortic regurgitation. Repeat transthoracic echocardiography using multiple transducer angulations and a narrow color Doppler sector angle in one patient and a color Doppler M-Mode study in the second patient proved useful in excluding the presence of severe aortic regurgitation.

Adult↗