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Bijoy K Khandheria

Publications and source records attributed to Bijoy K Khandheria.

At least 19 recordsLinked to original sources
PubMed2006

Role of biplane and biplane echocardiographically guided 3-dimensional echocardiography during dobutamine stress echocardiography.

Image acquisition time and wall-motion score of conventional 2-dimensional (2D) dobutamine stress echocardiography (DSE) were compared with those of biplane and 3-dimensional (3D) DSE in 50 patients (age 67 +/- 13 years) with regular rhythms during clinically indicated DSE. Commercially available systems were used for the study. We used a conventional transducer for 2D and a matrix-array transducer (x4 or x3-1) for two biplane (60- and 120-degree) images and one 3D full-volume image. Image quality was scored as 1 = good; 2 = adequate; and 3 = inadequate. Segmental wall-motion scores for each method were analyzed in blinded fashion. Acquisition times of biplane (9.3 +/- 2.8 seconds) and biplane-guided 3D (additional 2.6 +/- 1.0 seconds) echocardiography were significantly shorter than those of conventional 2D DSE (60.0 +/- 26.7 seconds) (P < .001). Image quality was adequate or good in 94% for biplane and 96% for 3D echocardiography. Agreement of segmental wall-motion score was present in 87.6% of segments for 2D versus biplane and 85.9% for 2D versus 3D at baseline and in 88.0% for 2D versus biplane and 87.4% for 2D versus 3D at peak stress. Acquisition of biplane or biplane-guided 3D volumetric data during DSE with use of a new matrix-array transducer was feasible and shortened image acquisition time without affecting the diagnostic yield compared with conventional 2D imaging.

Aged↗
PubMed2006

Right ventricular metastasis of uterine squamous cell carcinoma.

This imaging case report demonstrates abnormal right ventricular masses of primarily unknown origin. The woman was admitted because of right heart failure symptoms. Echocardiography showed the masses exclusively related to the right ventricular endomyocardium and extending through the entire length and breadth of the ventricle. Systolic function was normal without evidence of outflow tract obstruction. The patient died in 3 days because of multisystem failure. Autopsy findings confirmed metastasis on the right ventricle and histopathology demonstrated the infrequent finding of metastasis from uterine squamous cell carcinoma, which had been operated on 5 years before.

Aged, 80 and over↗
PubMed2006

Population-based study of the relationship between patent foramen ovale and cerebrovascular ischemic events.

OBJECTIVE: To determine whether patent foramen ovale (PFO) is a risk factor for a cryptogenic cerebrovascular ischemic event (CIE). METHODS: This case-control study of 1072 residents of Olmsted County, Minnesota, who underwent contrast transesophageal echocardiography between 1993 and 1997 included 519 controls without CIE randomly selected from the population, 262 controls without CIE referred for transesophageal echocardiography because of cardiac disease, 158 cases with incident CIE of obvious cause (noncryptogenic), and 133 cases with incident CIE of uncertain cause (cryptogenic). RESULTS: Large PFOs were detected in 108 randomly selected controls (20.8%), 22 referred controls (8.4%), 17 noncryptogenic CIE cases (10.8%), and 22 cryptogenic CIE cases (16.5%). After adjustment for age, sex, hypertension, smoking, atrial fibrillation, ischemic heart disease, and number of contrast injections, the presence of a large PFO was not significantly associated with group status (P=.07). Using the odds of the presence of large PFO in the randomly selected controls as the reference, the odds ratio (95% confidence interval) of the presence of large PFO was 0.47 (0.26-0.87) for referred controls, 0.69 (0.37-1.29) for noncryptogenic CIE cases, and 1.10 (0.63-1.90) for cryptogenic CIE cases. CONCLUSIONS: Patent foramen ovale is not a risk factor for cryptogenic ischemic stroke or transient ischemic attack in the general population. The PFO's importance in the genesis of cryptogenic CIE may have been overestimated in previous studies because of selective referral of cases and underascertainment of PFO among comparison groups of patients referred for echocardiography for clinical indications other than cryptogenic CIE.

Adult↗
PubMed2006

Population-based study of the relationship between atherosclerotic aortic debris and cerebrovascular ischemic events.

OBJECTIVE: To assess the validity of the suggestion that protruding atheromatous material in the thoracic aorta is an important cause of cerebrovascular ischemic events (CIEs) (ie, transient ischemic attack or ischemic stroke). METHODS: This case-control study of Olmsted County, Minnesota, residents who underwent transesophageal echocardiography (TEE) from 1993 to 1997 included controls without CIE randomly selected from the population, controls without CIE referred for TEE because of cardiac disease, cases with incident CIE of obvious cause (noncryptogenic), and cases with incident CIE of uncertain cause (cryptogenic). RESULTS: Of the 1135 subjects, 520 were randomly selected controls without CIE, 329 were controls without CIE referred for TEE, 159 were noncryptogenic CIE cases, and 127 were cryptogenic CIE cases. Complex atherosclerotic aortic debris in ascending and transverse segments of the arch was detected in 8 randomly selected controls (1.5%), 13 referred controls (4.0%), and 15 noncryptogenic (9.4%) and 4 cryptogenic (3.1%) CIE cases. After adjusting for age, sex, hypertension, smoking, atrial fibrillation, valvular heart disease, congestive heart failure, and atherosclerosis other than in the thoracic aorta, complex atherosclerotic aortic debris was not significantly associated with group status. With randomly selected controls as the referent group, odds ratios (95% confidence intervals) were 1.72 (0.61-4.87) for referred controls, 3.16 (1.18-8.51) for noncryptogenic CIE cases, and 1.39 (0.39-4.88) for cryptogenic CIE cases. CONCLUSIONS: Complex atherosclerotic aortic debris is not a risk factor for cryptogenic ischemic stroke or transient ischemic attack but is a marker for generalized atherosclerosis and well-established atherosclerotic and cardioembolic mechanisms of cerebral ischemia. Embolization from the aorta is not a common mechanism of ischemic stroke or transient ischemic attack.

Aged↗
PubMed2005

Patent foramen ovale: innocent or guilty? Evidence from a prospective population-based study.

OBJECTIVES: We sought to determine the association between patent foramen ovale (PFO), atrial septal aneurysm (ASA), and stroke prospectively in a unselected population sample. BACKGROUND: The disputed relationship between PFO and stroke reflects methodologic weaknesses in studies using invalid controls, unblinded transesophageal echocardiography examinations, and data that are unadjusted for age or comorbidity. METHODS: The use of transesophageal echocardiography to identify PFO was performed by a single echocardiographer using standardized definitions in 585 randomly sampled, Olmsted County (Minnesota) subjects age 45 years or older participating in the Stroke Prevention: Assessment of Risk in a Community (SPARC) study. RESULTS: A PFO was identified in 140 (24.3%) subjects and ASA in 11 (1.9%) subjects. Of the 140 subjects with PFO, 6 (4.3%) had an ASA; of the 437 subjects without PFO, 5 had an ASA (1.1%, two-sided Fisher exact test, p = 0.028). During a median follow-up of 5.1 years, cerebrovascular events (cerebrovascular disease-related death, ischemic stroke, transient ischemic attack) occurred in 41 subjects. After adjustment for age and comorbidity, PFO was not a significant independent predictor of stroke (hazard ratio 1.46, 95% confidence interval 0.74 to 2.88, p = 0.28). The risk of a cerebrovascular event among subjects with ASA was nearly four times higher than that in those without ASA (hazard ratio 3.72, 95% confidence interval 0.88 to 15.71, p = 0.074). CONCLUSIONS: These prospective population-based data suggest that, after correction for age and comorbidity, PFO is not an independent risk factor for future cerebrovascular events in the general population. A larger study is required to test the putative stroke risk associated with ASA.

Aged↗
PubMed2005

Apex-to-base dispersion in regional timing of left ventricular shortening and lengthening.

OBJECTIVES: We investigated whether the onset and progression of regional left ventricular (LV) shortening and lengthening parallel the apex-to-base differences in depolarization and repolarization. BACKGROUND: Limited information exists regarding apex-to-base differences in longitudinal and circumferential deformation sequence of the LV. METHODS: The apex-to-base differences in electric activation and the progression of longitudinal and circumferential shortening and lengthening sequences were determined in 8 porcine beating hearts in situ by implanting bipolar electrodes and an array of 14 sonomicrometry crystals in the LV free wall. RESULTS: Electric activation started at the apical subendocardium and showed significant delay in reaching the LV base. The onsets of mechanical activation and subsequent 20%, 40%, and 80% peak longitudinal shortenings required longer time to occur at base compared to the apex. The repolarization sequence propagated in reverse, with the base repolarizing before the apex. Subendocardial longitudinal shortening at base and subepicardial circumferential shortening at apex continued beyond the period of LV ejection, resulting in an apex-to-base gradient in the onset of lengthening. This gradient correlated with the duration of isovolumic relaxation (r = 0.85, p = 0.004) and the time required for reaching the lowest LV diastolic pressure (r = 0.70, p = 0.04). CONCLUSIONS: Apex-to-base delay in mechanical shortening of LV parallels the apex-to-base direction of the electric activation sequence. Basal subendocardial and apical subepicardial regions deform through a characteristic phase of postsystolic shortening. Short-lived apex-to-base and subendocardial-to-subepicardial relaxation gradients at the onset of diastole may have a physiologic significance in facilitating active restoration of the LV cavity in diastole.

Animals↗
PubMed2005

Biphasic tissue Doppler waveforms during isovolumic phases are associated with asynchronous deformation of subendocardial and subepicardial layers.

Subendocardial and subepicardial layers of the left ventricle (LV) are characterized with right- and left-handed helical orientations of myocardial fibers. We investigated the origin of biphasic deformations of the LV wall during isovolumic contraction (IVC) and relaxation (IVR). In eight open-chest adult pigs, strain rates were measured along the right- and left-handed helical directions in the LV anterior wall by implanting 16 sonomicrometry crystals. Sonomicrometry strain rates were compared with the longitudinal subendocardial strain rates obtained by tissue Doppler imaging. During ejection and diastolic filling, shortening and lengthening occurred synchronously along the right- and left-handed helical directions. However, during IVC and IVR, the deformations were dissimilar in the two directions. Transmural shortening during IVC occurred along the right-handed helical direction and was accompanied with transient lengthening in the left-handed helical direction. Conversely, during IVR, the LV lengthened along the left-handed helical direction and shortened in the right-handed helical direction. Peak subendocardial strain rates obtained by tissue Doppler imaging during IVC and IVR correlated with corresponding sonomicrometry strain rate values obtained along the right- and left-handed helical directions (r = 0.81, P < 0.001 and r = 0.70, P = 0.001, respectively). Our data suggest that brief counterdirectional movements occur within the LV wall during IVC and IVR. Shortening along the right-handed helical direction is accompanied with reciprocal lengthening in the left-handed helical direction during IVC and vice versa during IVR. The results support an association between asynchronous deformation of subendocardial and subepicardial muscle fibers and the biphasic isovolumic movements observed with high-resolution tissue Doppler imaging.

Animals↗
PubMed2005

Clinical, laboratory, and transesophageal echocardiographic correlates of interatrial septal thickness: a population-based transesophageal echocardiographic study.

BACKGROUND: The determinants of interatrial septal (IAS) thickening ("lipomatous hypertrophy"), a common echocardiographic finding in the elderly, are poorly defined. The objective of this study was to determine the clinical, laboratory, and transesophageal echocardiographic correlates of IAS thickening in the general population. METHODS: The thickness of the IAS was measured by transesophageal echocardiography in 384 patients (median age: 66 years; range: 51-101 years; 53% men) participating in a population-based study (Stroke Prevention: Assessment of Risk in a Community). The associations between atherosclerosis risk factors, clinical cardiovascular disease, aortic atherosclerotic plaques, and IAS thickness were examined. RESULTS: Age and body surface area (BSA) were significantly associated with IAS thickness (median: 6 mm; range: 2-17 mm). IAS thickness increased by 12.6% per 10 years of age (95% confidence interval: 9.0-16.4%) adjusting for sex and BSA, and increased by 7.0% per 0.1 m 2 BSA (confidence interval: 5.0-9.2%) adjusting for age and sex. Overall, age, sex, and BSA accounted for 22.5% of the variability in IAS thickness. Current smoking (20.4% increase in IAS thickness in current smokers) and hypertension treatment (8.5% increase in treated patients) were associated with increased IAS thickness, adjusting for age, sex, and BSA ( P < .05), but these two risk factor variables jointly explained only an additional 2.3% of the variability in IAS thickness beyond the variability explained by age, sex, and BSA. Clinical coronary artery and cerebrovascular disease, atrial arrhythmias, and aortic atherosclerotic plaques were not associated with IAS thickness, adjusting for age, sex, and BSA ( P > .3). CONCLUSIONS: IAS thickening is an age-associated process. Atherosclerosis risk factors are weakly associated with IAS thickening, whereas atherosclerotic vascular disease is not.

Age Factors↗
PubMed2005

Role of biplane echocardiography in a large-volume clinical practice: revamping strategies for echocardiography in a limited time.

OBJECTIVES: We determined the feasibility, learning curve, time efficacy, and the quality of imaging during biplane echocardiography performed in clinical practice with a view to reduce a sonographer's time for image acquisition. BACKGROUND: Multidimensional echocardiographic imaging has improved the assessment of cardiac geometry and function in clinical settings. However, concerns regarding ease of performance and effects on overall clinical work flow remain inadequately addressed. METHODS: The study included 100 consecutive unselected patients referred to our echocardiography laboratory. They were randomized to conventional or biplane echocardiography performed by a sonographer without previous knowledge of biplane imaging. Image acquisition time and variables influencing the learning curve and overall image quality were analyzed. RESULTS: Mean time required for biplane and mono-plane imaging was not different in the first 24 cases. In the remaining cases, mean image acquisition time was reduced significantly in 58 cases (76.3%): biplane, 5.6 minutes (SD 1.3); and monoplane, 6.6 minutes (SD 1.6) ( P = .0003). For both techniques, scanning time was not affected by referral pattern, body habitus, or underlying cardiac lesion. Overall, biplane scanning resulted in reduction in echocardiographic imaging time of 9.1%, maintaining an acceptable image quality in 87% of patients. In the last 20 cases, new software design and superior instrumentation technique improved the mean time gain to 15%. CONCLUSION: In a high-volume echocardiography laboratory, biplane imaging effectively reduces sonographer time for imaging and improves throughput by increasing the number of comprehensive ultrasound studies that can be performed in a limited time.

Cardiovascular Diseases↗
PubMed2005

Doppler tissue imaging improves assessment of abnormal interventricular septal and posterior wall motion in constrictive pericarditis.

We hypothesized that Doppler tissue imaging in the short axis would provide enhanced quantitative information for differentiating the pattern and extent of abnormal septal and posterior wall motion in constrictive pericarditis (CP). Using quantitative pulsed wave and color M-mode Doppler tissue imaging, we quantified the pattern of abnormal septal and posterior wall motion and studied its incremental advantage over conventional M-mode and 2-dimensional echocardiography in 40 patients with surgically proven CP. The pattern and extent of abnormalities were compared with 35 age- and sex-matched control subjects and 20 patients with abnormal septal motion of other causes. In 33 patients (82.5%) with CP, the interventricular septum showed high-velocity (>7 cm/s) early diastolic biphasic motion with or without multiple recoil waves (polyphasic diastolic septal fluttering). In the posterior wall, the early diastolic wave was normal but the late diastolic wave was reduced in 24 patients (60%) and absent in 7 (17.5%). In comparison, M-mode and 2-dimensional echocardiography identified abnormal septal or posterior wall motion in 24 patients (60%) ( P = .003). The pattern of abnormal septal motion in CP could be differentiated from abnormal septal motion of other causes in 16 patients (80%). The overall sensitivity and specificity of high-velocity polyphasic septal flutter for differentiating CP from control cases and other diseases was 82.5% and 92.7%, respectively. In CP, Doppler tissue imaging in the short axis provides unique diagnostic information and reliably differentiates CP from control cases and most other causes of abnormal septal motion.

Adult↗
PubMed2005

Quantification of regional nonuniformity and paradoxical intramural mechanics in hypertrophic cardiomyopathy by high frame rate ultrasound myocardial strain mapping.

This study tested the hypothesis that linear mapping of regional myocardial strain comprehensively assesses variations in regional myocardial function in hypertrophic cardiomyopathy. Hypertrophic cardiomyopathy is characterized by disorganized myocardial architecture that results in spatial and temporal nonuniformity of regional function. Left ventricular deformation was quantified in 20 patients with hypertrophic cardiomyopathy and compared with 25 age- and sex-matched control subjects. Abnormalities in subendocardial strain ranged from reduced longitudinal shortening to paradoxical systolic lengthening and delayed regional longitudinal contractions that were often located in small subsegmental areas. These variations were underestimated significantly by arbitrary measurements compared with linear mapping, in which a region of interest was moved across the longitudinal length of left ventricle (difference of peak and least strain, 10.7% +/- 5.1% vs 17% +/- 5.5%; P < .001). Echocardiographic assessment of variations in regional strain requires careful mapping and may be inappropriately assessed if left ventricular segments are sampled at arbitrary focal locations.

Adult↗
PubMed2004

Left atrial myopathy in cardiac amyloidosis: implications of novel echocardiographic techniques.

AIMS: To assess left atrial (LA) function and determine the prevalence of LA dysfunction in AL amyloidosis (AL) using conventional and strain echocardiography. METHODS AND RESULTS: LA ejection fraction, LA filling fraction, LA ejection force, peak LA systolic strain rate (LAsSR), and LA systolic strain (LA epsilon) were determined in 95 AL patients (70 with and 25 without echocardiographic evidence of cardiac involvement, abbreviated CAL and NCAL, respectively), 30 age-matched controls (CON), and 20 patients with diastolic dysfunction and LA dilatation (DD). Peak LAsSR >2 standard deviations below mean CON value was used as the cut-off for normal LA function. LA ejection fraction was lower in CAL when compared with CON (40.4+/-13.6 vs. 67.0+/-6%, P=0.01). Left atrial septal strain rate and strain were lower in CAL (0.8+/-0.5 s(-1) and 5.5+/-4%, respectively) compared with CON (1.8+/-0.8 s(-1) and 14+/-4%, respectively, P=<0.0001), NCAL (1.6+/-0.8 s(-1) and 13+/-7%, respectively, P<0.0001) and DD (1.3+/-0.4 s(-1) and 10+/-2%, respectively, P<0.0001). Based on peak LA systolic strain rate criteria, the cut-off values for normal LA function were -1.1 s(-1) and -1.05 s(-1) for lateral and septal walls. Using these criteria, LA dysfunction was identified in 32% (lateral LA criteria) and 60% (septal LA criteria) of CAL patients. Lateral and septal LAsSR were lower in CAL patients with vs. those without symptoms of heart failure. Inter- and intra-observer agreement was high for LA strain echocardiography. CONCLUSION: LA function assessment using strain echocardiography is feasible with low intra- and inter-observer variability. LA dysfunction is observed in AL patients without other echocardiographic features of cardiac involvement and may contribute to cardiac symptoms in CAL.

Aged↗
PubMed2004

C-reactive protein and atherosclerosis of the thoracic aorta: a population-based transesophageal echocardiographic study.

BACKGROUND: An association between systemic inflammatory markers and the presence and severity of atherosclerotic plaques has not been demonstrated in a nonselected population. The purpose of this study was to examine the association of inflammatory markers with aortic atherosclerotic plaques in a sample of the general population and in a subgroup free of clinical vascular disease. METHODS: Transesophageal echocardiography was performed in 386 subjects (median age, 66 years; 53% men). We examined the association between systemic inflammatory markers and aortic atherosclerotic plaques. RESULTS: Aortic plaques were present in 267 subjects (69%). Plaques at least 4 and 6 mm thick and mobile debris were present in 114, 41, and 20 subjects, respectively. High-sensitivity C-reactive protein (hs-CRP) level was associated with the presence of aortic plaques, adjusting for age, sex, smoking status, and additional atherosclerosis risk factors. Among subjects with plaques, hs-CRP level was independently associated with plaques at least 6 mm thick; similar trends were observed for the associations of hs-CRP level with plaques at least 4 mm thick and mobile debris. In subjects with aortic plaques who were free of clinically apparent coronary artery or cerebrovascular disease, hs-CRP level was independently associated with plaques at least 6 mm thick. CONCLUSIONS: Level of hs-CRP is independently associated with the presence and severity of aortic atherosclerotic plaques. These observations establish the association of systemic inflammation with anatomically defined atherosclerosis in the general population.

Age Distribution↗
PubMed2004

Atherosclerosis of the aorta: risk factor, risk marker, or innocent bystander? A prospective population-based transesophageal echocardiography study.

OBJECTIVES: The goal of this study was to investigate whether complex aortic atherosclerosis is associated with increased risk of vascular events in a non-selected population. BACKGROUND: In selected high-risk patients, aortic atherosclerosis is associated with increased risk of vascular events. METHODS: We describe the relationship between simple versus complex (>4-mm thick or mobile debris) aortic atherosclerotic plaques and vascular events during follow-up in a random sample of 585 persons (age > or =45 years) using 1993 to 2000 data from the Stroke Prevention: Assessment of Risk in a Community (SPARC), a prospective population-based longitudinal study. RESULTS: At five-year median follow-up (range, 0.5 to 6.5 years), cardiac events (death, non-fatal myocardial infarction, coronary revascularization, heart failure associated with coronary artery disease) and cerebrovascular events (ischemic fatal and non-fatal strokes, transient ischemic attacks) had occurred in 95 subjects and 41 subjects, respectively. Age, male gender, prior coronary artery disease, higher pulse pressure, and diabetes were significant cardiovascular predictors. Age, prior myocardial infarction, and a history of atrial fibrillation were significant cerebrovascular predictors. Simple aortic plaques (253 persons) were not independently associated with either cardiac or cerebrovascular events. Complex plaques (44 persons) were marginally associated with cardiac events, adjusting for age and gender (hazard ratio [HR], 2.28; 95% confidence interval [CI], 1.11 to 4.68; p = 0.053 for two degrees of freedom [complex and simple plaques vs. no plaques]) but not after adjusting for additional clinical risk factors (HR, 1.22; 95% CI, 0.57 to 2.62; p = 0.64). Complex plaques were associated with cerebrovascular events only univariately. CONCLUSIONS: Aortic atherosclerotic plaques are not associated with future cardiac or cerebrovascular events. Aortic atherosclerosis may not be an independent risk factor for vascular events in the general population.

Aged↗
PubMed2004

Comparison of echocardiographic features of noncompaction of the left ventricle in adults versus idiopathic dilated cardiomyopathy in adults.

Noncompaction of left ventricular myocardium (NCLV), or "spongy myocardium," in adults represents an arrest in endomyocardial morphogenesis and occurs as an isolated cardiomyopathy. Because NCLV can be readily mistaken for idiopathic dilated cardiomyopathy, echocardiographic features other than the structural features of the myocardial wall need to be carefully defined for distinguishing the 2 conditions. This study was therefore designed to characterize the echocardiographic features that could be useful for differentiating NCLV from idiopathic dilated cardiomyopathy.

Adult↗