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Navin C Nanda

Publications and source records attributed to Navin C Nanda.

At least 19 recordsLinked to original sources
PubMed2007

Role of echocardiography in the diagnostic assessment and etiology of heart failure in the elderly--opacify, quantify, and rectify.

Echocardiography offers comprehensive, noninvasive, and relatively inexpensive tools for diagnosing cardiac pathology in the elderly. With an organized approach using two-dimensional echocardiography and Doppler echocardiography, clinicians can determine the systolic and diastolic left ventricular performance;estimate the cardiac output, pulmonary artery, and ventricular fill-ing pressures; and identify surgically correctable valve disease.Meanwhile, real-time three-dimensional echocardiography provides unprecedented volume data to quantify the left ventricular status. Tissue Doppler-derived myocardial velocity and strain imaging data provide extremely fine details about the regional variations in myocardial synchrony and predict responders to cardiac resynchronization therapy. Thus, echocardiographic tools provide the basis for determining when to attempt to rectify the left ventricular dysfunction with strategically placed, biventricular pace-maker leads.

Aged↗
PubMed2007

Assessment of surgically unroofed coronary sinus by live/real time three-dimensional transthoracic echocardiography.

Both two-dimensional transthoracic echocardiography (2DTTE) and live/real time three-dimensional transthoracic echocardiography (3DTTE) were attempted in a 25-year-old morbidly obese female with total anomalous pulmonary venous return (TAPVR) into the coronary sinus (CS) in whom surgical unroofing of CS with patch closure of CS ostium was performed in infancy to redirect pulmonary venous flow into the left atrium (LA). The patient had become increasingly symptomatic over the past 1 year because of severe left-to-right shunting due to dehiscence of the patch used to close the CS ostium. Despite a poor acoustic window, 3DTTE was able to identify a communication between the LA and CS which resulted from surgical unroofing of the CS as well as flow signals moving into the right atrium from the CS. These findings were not detected by 2DTTE.

Adult↗
PubMed2006

Native aortic valve insufficiency in patients with left ventricular assist devices.

Management of mild to moderate aortic insufficiency in patients with a left ventricular assist device remains controversial. We report 3 patients with aortic insufficiency and pulsatile left ventricular assist devices treated with a central aortic valve coapting suture. Two of the repairs have been durable for more than 1 year and aspirin appears to be sufficient anticoagulation.

Aged↗
PubMed2006

Two-dimensional transthoracic contrast echocardiographic assessment of metastatic left ventricular tumors.

To illustrate the usefulness of contrast echocardiography in the assessment of cardiac tumors, we present an 81-year-old female with pathological fracture of the right clavicle in whom biopsy showed poorly differentiated carcinoma. Two-dimensional transthoracic echocardiography found two masses in the left ventricle attached to mid-ventricular septum consistent with metastases. Echo contrast study with octafluoropropane (Optison) showed contrast enhancement of both the masses consistent with high vascularity seen in a malignant tumor.

Aged, 80 and over↗
PubMed2006

Incremental value of live/real time three-dimensional transthoracic echocardiography in the assessment of left ventricular thrombi.

This is a case series on three adult patients who contain left ventricular (LV) thrombus and the incremental benefits of live/real time three-dimensional transthoracic echocardiography (3DTTE) in comparison to two-dimensional transthoracic echocardiography (2DTTE) in evaluating LV thrombi. These cases illustrate that 3DTTE is of additional benefit by demonstrating the following: (1) cropping of a single 3DTTE apical dataset may be enough to provide comprehensive assessment of the LV in a timely manner even without breath holding in a not fully cooperative patient (2) it identifies the exact point of attachment of the thrombus to the left ventricular wall, (3) helps to delineate the absence or presence of focal echolucent areas within thrombi indicative of the presence and extent of clot lysis, which may have potential therapeutic and prognostic implications, and (4) provides more accurate assessment of thrombus mobility which has prognostic indications.

Adult↗
PubMed2006

Definitive diagnosis of descending thoracic aortic dissection by real time/live three-dimensional transthoracic echocardiography.

We describe a patient with descending thoracic aortic dissection in whom three- dimensional transthoracic echocardiography was able to clearly visualize the dissection flap en face as a sheet of tissue, as well as demonstrate a large communication between the true and false lumen in three dimensions, enabling a definitive diagnosis of dissection.

Aortic Dissection↗
PubMed2006

Usefulness of live/real time three-dimensional transthoracic echocardiography in the characterization of ventricular septal defects in adults.

In this report, we present 12 patients (range 14-76 years, mean 40 +/- 22.7 years) who underwent surgical repair of a ventricular septal defect (VSD). Location, size, and surrounding anatomy of the VSD were assessed prior to intervention in all patients with live/real time three-dimensional transthoracic echocardiography (3DTTE). In 9 patients, measurements of maximum dimension, circumference, and area by 3DTTE correlated well with the same measurements from intraoperative three-dimensional transesophageal echocardiographic (3DTEE) reconstruction. 3DTTE measurement of maximum dimension of VSDs also agreed well with maximum dimension by surgery in 10 patients. Live/real time 3DTTE accurately defined VSD location, size, and surrounding anatomy in all patients studied by us. VSD characterization by live 3DTTE agreed well with surgery descriptions and 3DTEE measurements.

Adolescent↗
PubMed2006

Usefulness of live/real time three-dimensional transthoracic echocardiography in the identification of individual segment/scallop prolapse of the mitral valve.

In this report, we present 34 patients in whom surgical intervention was undertaken for severe mitral insufficiency due to mitral valve prolapse (MVP). Location and severity of MVP and regurgitation were assessed preoperatively by live/real time three-dimensional transthoracic echocardiography and closely agreed with the surgical findings.

Adult↗
PubMed2006

Usefulness of live/real time three-dimensional transthoracic echocardiography in the assessment of atrioventricular septal defects.

We studied nine patients (five newborns and infants, two children, and two adults) with atrioventricular septal defects (four complete, one intermediate, and four partial) utilizing live/real time three-dimensional transthoracic echocardiography (3DTTE) and a 4-MHz matrix array transducer. In all patients, 3DTTE provided additional morphological and/or functional information as compared to standard two-dimensional transthoracic echocardiography (2DTTE). 3DTTE may be a useful supplement to 2DTTE in the assessment of atrioventricular septal defects.

Adult↗
PubMed2006

Live/real time three-dimensional echocardiographic demonstration of left ventricular noncompaction and thrombi.

We describe two adult patients with left ventricular noncompaction in whom live/real time three-dimensional transthoracic echocardiography (3DTTE) supplemented two-dimensional transthoracic echocardiography in making a definitive diagnosis of clots coexisting with trabeculations in the left ventricle. Mobility of clots and the presence of central echolucencies consistent with clot lysis were best demonstrated by 3DTTE and served to confidently differentiate clots from adjacent trabeculations.

Adult↗
PubMed2006

Quantification of tricuspid regurgitation by live three-dimensional transthoracic echocardiographic measurements of vena contracta area.

We evaluated tricuspid regurgitation (TR) by multiple echocardiographic techniques in 93 consecutive patients who underwent standard two-dimensional (2D) and live three-dimensional (3D) transthoracic echocardiography (TTE). TR vena contracta (VC) area was obtained by 3D TTE by systematic and sequential cropping of the acquired 3D TTE dataset. Assessment of VC area by 3D TTE was compared to 2D TTE measurements of the ratio of TR regurgitant jet area to right atrial area (RJA/RAA), RJA alone, VC width, and calculated VC area. VC area from 3D TTE closely correlated with RJA/RAA and RJA alone as determined from 2D TTE measurements. Live 3D TTE color Doppler measurements of VC area can be used for quantitative assessment of TR and offer incremental value for quantification of particularly severe regurgitant lesions.

Adolescent↗
PubMed2006

Cor triatriatum sinister: assessment by live/real time three-dimensional transthoracic echocardiography.

We report a 49-year-old morbidly obese female with a poor acoustic window in whom live/real time three-dimensional transthoracic echocardiography was able to make a confident diagnosis of cor triatriatum sinister. En face views of the membrane facilitated accurate assessment of the size and shape of the large nonobstructing opening in the membrane. Maximum dimensions of the opening were 3.06 x 1.03 cm and area was 2.3 cm(2).

Computer Systems↗
PubMed2006

Papillary fibroelastoma of the pulmonary valve: assessment by live/real time three-dimensional transthoracic echocardiography.

The differential diagnosis of a cardiac valve mass includes fibroelastoma, myxoma, lipoma, Lambl's excrescences, thrombus, and vegetation. Fibroelastomas are extremely rare primary cardiac tumors. Their incidence is 0.00017-0.033% in autopsy series and 0.019% in clinical series identified on echocardiography. Although rare, fibroelastomas are the most common tumors affecting the cardiac valves with aortic, mitral, tricuspid, and pulmonary valves being involved in this order. In the current report we describe a case of pulmonary valve mass in which a confident prospective diagnosis of fibroelastoma could be made utilizing the technique of three-dimensional transthoracic echocardiography.

Adult↗
PubMed2006

Tissue Doppler assessment of longitudinal right and left ventricular strain and strain rate in pulmonary artery hypertension.

Tissue Doppler imaging (TDI) in 38 adult patients with pulmonary artery hypertension of varied etiology and normal left ventricular systolic function by two-dimensional transthoracic echocardiography showed significantly reduced peak systolic strain (SS) in all three segments of left ventricular free wall and ventricular septum and two of three segments of right ventricular free wall when compared to 29 adults with no clinical or echocardiographic evidence of heart disease and normal left and right ventricular systolic function. A similar reduction in peak diastolic strain (DS) was also noted in all three segments of left ventricular free wall and ventricular septum and one of three segments of right ventricular free wall. This reduction in strain indices in patients with pulmonary hypertension was noted irrespective of whether right ventricular systolic function was normal or reduced as assessed by two-dimensional transthoracic echocardiography. SS and DS rates also showed reductions in patients with pulmonary artery hypertension. Our study shows the potential value of TDI indices in identifying reduced regional left ventricular systolic and diastolic longitudinal function in patients with pulmonary artery hypertension and normal left ventricular systolic function by two-dimensional transthoracic echocardiography. This reduction in left ventricular function was noted in patients with both normal and reduced right ventricular systolic functions by two-dimensional echocardiography.

Adult↗
PubMed2005

Relation between effects of adenosine on brachial artery reactivity and perfusion pattern in patients with known or suspected coronary artery disease.

This study examined the changes in brachial artery diameter and flow velocity in response to intravenous adenosine and compared the results to cuff occlusion and single-photon emission computed tomographic (SPECT) images. The change in diameter was less with adenosine than with cuff occlusion. There was no correlation between the presence of abnormal SPECT images and the responses to adenosine or cuff occlusion in either diameter or flow velocity.

Adenosine↗
PubMed2005

Principles of intracardiac echocardiography.

The development of newer electrophysiological mapping and ablation procedures for the treatment of complex arrhythmias has led to the advent of a new application of echocardiography. The introduction of intracardiac echocardiography to the electrophysiology laboratory has created a marriage between imaging and intervention that is generating new insights for the echocardiographer and added safety for the electrophysiologist. This review will discuss the history, principles, approaches, and potential future applications of intracardiac echocardiography.

Coronary Vessels↗
PubMed2005

Dual site right atrial pacing can improve the impact of standard dual chamber pacing on atrial and ventricular mechanical function in patients with symptomatic atrial fibrillation: further observations from the dual site atrial pacing for prevention of atrial fibrillation trial.

BACKGROUND: The effects of atrial pacing mode on atrial and ventricular function in patients with atrial fibrillation (AF) and bradycardia have not been evaluated. We evaluated atrial and ventricular function during randomization to support pacing (SP), high right atrial pacing (HRA), and dual site right atrial pacing (DAP). METHODS: Seventy-nine patients (66 +/- 12 yr, 46 male) with standard pacing indications and symptomatic AF were randomized to each of three pacing modes (DAP, HRA, SP) for 6 months in a crossover design. Echocardiographic studies were performed at enrollment and the end of each mode. Paired comparisons of atrial and ventricular function parameters were performed between each pacing mode and baseline. RESULTS: HRA pacing in DDDR mode resulted in increased left ventricular (LV) end systolic volume (78 +/- 42 vs. 60 +/- 31 ml, p = 0.001) and reduced LV ejection fraction (44 +/- 14 vs. 50 +/- 11%, p = 0.007) compared to baseline. These parameters did not change during DAP. DAP resulted in increased peak A wave velocity (75 +/- 19 vs. 63 +/- 23 cm/s, p = 0.003) and atrial filling fraction compared to baseline (0.47 +/- 0.15 vs. 0.38 +/- 0.13, p = 0.005). Atrial and ventricular function were similar between control and SP. CONCLUSION: DAP, but not HRA or SP, improved left atrial (LA) function in patients with AF and bradycardia. HRA pacing in DDDR mode resulted in LA dilatation and deterioration of LV function which was not observed with DAP.

Aged↗