Search PubMed⌕ Search

Biomedical subjects

K K Talwar

Publications and source records attributed to K K Talwar.

At least 19 recordsLinked to original sources
PubMed2005

Low-density lipoprotein cholesterol estimation by a new formula in Indian population.

BACKGROUND: Estimation of low-density lipoprotein cholesterol is crucial in the management of ischemic heart disease patients. Low-density lipoprotein cholesterol is routinely calculated in laboratories world over by applying Friedewald formula for logistic reasons. We derived a new formula based on multiple regression approach. METHODS: Lipid profiles were done on blood samples of 2008 patients. In initial 1000 patients, low-density lipoprotein cholesterol was estimated by a direct method and also by Friedewald formula. By applying linear regression methods on the data of direct estimation method, a new formula was obtained and the accuracy of this new formula was validated in the next 1008 patients. RESULTS: The mean low-density lipoprotein cholesterol was 116+/-41.5 mg/dl (3.02+/-1.08 mmol/l) measured by direct low-density lipoprotein cholesterol assay and that calculated by Friedewald formula was 119+/-46 mg/dl (3.09+/-1.2 mmol/l) for the initial 1000 patients. Low-density lipoprotein cholesterol measured by direct low-density lipoprotein cholesterol assay and calculated from Friedewald formula showed good correlation (r = 0.88), however, there was minimal overestimation by the Friedewald formula. The correlation improved between direct low-density lipoprotein cholesterol and calculated low-density lipoprotein cholesterol after excluding the patients with triglycerides more than 350 mg/dl (r = 0.92). The mean low-density lipoprotein cholesterol measured by the direct assay and by new formula in the next 1008 patients was 117+/-40 mg/dl (3.04+/-1.04 mmol/l) and 113.7+/-37 mg/dl (2.96+/-0.96 mmol/l), respectively with very good correlation (r = 0.97) between them. CONCLUSIONS: The new formula derived from multiple linear regression analysis appears to be more accurate than Friedewald formula in Indian population.

Algorithms↗
PubMed2005

Carotid intima-medial thickness as a marker of disease activity in Takayasu's arteritis.

BACKGROUND: Assessment of disease activity in patients with Takayasu's arteritis (TA) is difficult due to absence of definitive tests. Presence of carotid intima-medial thickening has been suggested as a possible marker of inflammation and disease activity. METHODS: We evaluated common carotid artery carotid intima-medial thickness (CCA-IMT) in 56 common carotid arteries (CCAs) in 28 healthy controls and 74 CCAs in 37 patients of TA. We correlated these findings with the presence of activity as assessed by the National Institutes of Health (NIH) criteria. RESULTS: CCA-IMT was increased (>0.8 mm) in 59% of the patients with TA. In patients with disease activity, the CCA-IMT was more than in those without activity (1.5+/-0.16 vs. 0.9+/-0.2 mm, P<0.005). This is presumably because of ongoing inflammation causing abnormal thickening. Even among patients without active disease, CCA-IMT was more than in controls (0.9+/-0.2 vs. 0.6+/-0.1 mm, P<0.05) possibly due to a milder degree of inflammation or healing with fibrosis. All patients with angiographic carotid obstruction had increased CCA-IMT irrespective of whether they were active or not. However, in patients with angiographically normal carotid arteries, CCA-IMT was increased only among the patients who were active (1.4+/-0.2 vs. 0.7+/-0.04, P<0.05). Abnormal CCA-IMT as marker of disease activity had a sensitivity of 82% and specificity of 60%. On excluding patients with increased CCA-IMT who had angiographic carotid stenosis (because the increase in CCA-IMT cannot be attributed entirely to activity alone in these patients), the specificity increased to 70%. CONCLUSION: Increased CCA-IMT is a reliable marker of active disease, especially in the absence of angiographically visible carotid disease.

Adolescent↗
PubMed2004

Comparison of echo and MRI in the imaging evaluation of intracardiac masses.

We compared the efficacy of echocardiography (ECHO) and magnetic resonance imaging (MRI) for evaluating intracardiac masses. Over an 8-yr period, 28 patients, 21 males, 7 females, 16 days-60 years of age (mean 25 years) with a suspected intracardiac mass on ECHO (transthoracic in all; transesophageal in 9) underwent an MRI examination. Five patients had a contrast-enhanced MRI. ECHO and MRI were compared with respect to their technical adequacy, ability to detect and suggest the likely etiology of the mass, and provide additional information (masses not seen with the other technique, inflow or outflow obstruction, and intramural component of an intracavitary mass). With MRI, the image morphology (including signal intensity changes on the various sequences) and extracardiac manifestations were also evaluated. The diagnosis was confirmed by histopathology in 18, surgical inspection in 4, by follow- up imaging on conservative management in 5, and by typical extracardiac manifestations of the disease in 1 patient. Fifteen (54%) patients had tumors (benign 12, malignant 3), 5 had a thrombus or hematoma, and 4 each had infective or vascular lesions. Thirty-four masses (13 in ventricle, 11 septal, 7 atrial, 2 on valve and 1 in pulmonary artery) were seen on MRI, 28 of which were detected by ECHO. Transthoracic ECHO (TTE) and MRI were technically optimal in 82% and 100% of cases, respectively. Nine patients needed an additional transesophageal ECHO (TEE). Overall, MRI showed a mass in all patients, whereas ECHO missed it in 2 cases. In cases with a mass on both modalities, MRI detected 4 additional masses not seen on ECHO. MRI suggested the etiology in 21 (75%) cases, while the same was possible with ECHO (TTE and TEE) in 8 (29%) cases. Intramural component, extension into the inflow or outflow, outflow tract obstruction, and associated pericardial or extracardiac masses were better depicted on MRI. We conclude that MRI is advantageous over a combination of TTE and TEE for the detection and complete morphological and functional evaluation (hemodynamic effects) of cardiac masses.

Adolescent↗
PubMed2004

Clinico-pathological evaluation of restrictive cardiomyopathy (endomyocardial fibrosis and idiopathic restrictive cardiomyopathy) in India.

BACKGROUND: Restrictive heart disease is characterized by impairment of ventricular filling during diastole with preserved systolic function. The clinical and histopathological profile on endomyocardial biopsy of a cohort of patients with restrictive cardiomyopathy (RCM) is presented. METHODOLOGY: The medical records of patients presenting with heart failure with systemic congestion, subsequently diagnosed as restrictive heart disease after evaluation including cardiac catheterisation, were studied retrospectively to determine the clinical spectrum of restrictive cardiomyopathy. The diagnosis of RCM was made, based on systemic congestion with dilated atria and near normal ventricular size and function. Only patients who had an endomyocardial biopsy were included in the study. Patients with chronic constrictive pericarditis and secondary restrictive heart disease mainly amyloidosis were excluded from the study. RESULTS: All 52 patients had heart failure with normal or near normal left ventricular size and function. Based on right and left ventricle angiography, patients were classified into two groups. Group I with findings suggestive of EMF (n=30) and Group II no evidence of EMF on angiography i.e. 'idiopathic RCM' (IRCM) (n=22). Baseline characteristics were similar in the two groups. Echocardiography revealed typical features of endomyocardial fibrosis in Group I patients, with apical obliteration of right and left ventricular apices. Group II patients had no apex obliteration (except in four patients, who were misclassified and in whom angiography did not show apex obliteration). The Group II patients had features of IRCM in the form of normal left and right ventricular size and function with restrictive features of doppler filling along with dilated left and right atria. Angiocardiography in EMF patients showed isolated RV involvement in only two patients. In the remaining 28 patients, the obliterative changes were biventricular with RV involvement more severe than LV involvement. Angiographic findings in Group II (IRCM) patients were unremarkable with preservation of normal trabecular pattern and absence of obliterative changes. Mild atrioventricular regurgitation was present in 10/22 patients. Histopathological examination revealed that endocardial thickening was more common (77% vs. 23%) in EMF patients. The presence of myocyte hypertrophy (70-80%), myocytolysis (40-50%) and interstitial fibrosis (46-56%) were similar in both groups. CONCLUSIONS: The majority of our patients had biventricular EMF. A significant number of patients had clinical hemodynamic features of restrictive heart disease but no evidence of EMF on angiography. These IRCM patients had similar clinical profiles to EMF but on endomyocardial biopsy the endocardial thickening was minimal and seen in few patients (5/22).

Adolescent↗
PubMed2004

High prevalence of insulin resistance in postpubertal Asian Indian children is associated with adverse truncal body fat patterning, abdominal adiposity and excess body fat.

OBJECTIVE: The objectives were to study the relationships of insulin resistance with generalized and abdominal obesity, and body fat patterning in urban postpubertal Asian Indian children. DESIGN: Cross-sectional, population-based epidemiological study. SUBJECTS: In all, 250 (155 males and 95 females) healthy urban postpubertal children. MEASUREMENTS: Anthropometric profile, percentage of body fat (%BF), fasting serum insulin, and lipoprotein profile. RESULTS: Fasting insulin correlated significantly with body mass index (BMI), %BF, waist circumference (WC), central and peripheral skinfold thicknesses and sum of four skinfold thicknesses (Sigma 4SF) in both sexes, and with systolic blood pressure and waist-to hip circumference ratio (W-HR) in males only. Consistent increase in fasting insulin was noted with increasing values of central skinfold thickness at each tertile of peripheral skinfold thickness, WC, and %BF. Central skinfold thickness correlated with fasting insulin even after adjusting for WC, W-HR, and %BF. The odds ratios (OR) (95% CI) of hyperinsulinemia (fasting insulin concentrations in the highest quartile) were 4.7 (2.4-9.4) in overweight subjects, 8 (4.1-15.5) with high %BF, 6.4 (3.2-12.9) with high WC, 3.7 (1.9-7.3) with high W-HR, 6.8 (3.3-13.9) with high triceps skinfold thickness, 8 (4.1-15.7) with high subscapular skinfold thickness, and 10.1 (5-20.5) with high Sigma 4SF. In step-wise multiple logistic regression analysis, %BF [OR (95% CI): 3.2 (1.4-7.8)] and Sigma 4SF [OR (95% CI): 4.5 (1.8-11.3)] were independent predictors of hyperinsulinemia, similar to insulin resistance assessed by HOMA (homeostatic model of assessment) in the study. CONCLUSION: A high prevalence of insulin resistance in postpubertal urban Asian Indian children was associated with excess body fat, abdominal adiposity, and excess truncal subcutaneous fat. Primary prevention strategies for coronary heart disease and diabetes mellitus in Asian Indians should focus on the abnormal body composition profile in childhood.

Abdomen↗
PubMed2003

Cardiac disease in pregnancy.

OBJECTIVES: To evaluate the maternal and fetal outcome of pregnancies complicated by cardiac disease in a developing country. METHODS: A retrospective analysis was carried out of 207 pregnancies in women with cardiac disease who delivered at >or=28 weeks of gestation from June 1994 through December 2000 at a tertiary care center. RESULTS: Rheumatic heart disease (n=183, 88%) with isolated mitral stenosis (n=71) was the predominant cardiac problem. Septal defects were the most common form of congenital heart disease (n=24). In 28 (13.52%) women, the diagnosis of cardiac disease was made during pregnancy. Cardiac complications were noted in 62 (29.95%) and fetal complications in 42 (20.28%) pregnancies. Patients in NYHA class I/II (n=175, 84.54%) had fewer maternal complications and their babies had a higher birth weight than those in NYHA class III/IV (n=32, 15.45%). Cardiac intervention was performed prior to pregnancy in 111 (60.65%) patients with rheumatic heart disease: PTMC/CMV in 73 and valve replacement (VR) in 38. Maternal and fetal outcome was better in patients with prosthetic valves (n=38) and the majority (97.4%) of them remained in NYHA class I/II. Cardiac intervention was safely carried out during pregnancy in 10 women (PTMC in 7, CMV in l, and VR in 2). One of them developed congestive cardiac failure during labor. None of the newborns of the 41 women who had received anticoagulants had any congenital malformation. CONCLUSIONS: Rheumatic heart disease was the predominant type. Patients in NYHA class I/II had a better maternal and fetal outcome than those in NYHA class III/IV. Surgical correction of the cardiac lesion prior to pregnancy was associated with better pregnancy outcome. Pregnant women with prosthetic valves tolerated pregnancy well.

Adolescent↗
PubMed2003

Correlations of C-reactive protein levels with anthropometric profile, percentage of body fat and lipids in healthy adolescents and young adults in urban North India.

OBJECTIVE: To investigate the relationships of sub-clinical inflammation and regional and generalized obesity and lipids in adolescent and young adult Asian Indians in north India. METHODS: We determined serum levels of C-reactive protein (CRP), a marker for sub-clinical inflammation, body mass index (BMI), waist circumference (WC), waist-to-hip ratio (W-HR), four skinfolds (biceps, triceps, subscapular and suprailiac), percentage of body fat (% BF) and lipid profile in 377 healthy adolescents and young adults (331 males and 46 females, age range: 14-25 years). RESULTS: Overweight subjects (BMI>85th percentile), and subjects with high values (>85th percentile) of WC and triceps skinfold thickness had significantly higher median CRP levels (P=0.04, P=0.001 and P=0.007, respectively) as compared with subjects with lower values of the variables. Elevated levels of CRP (>2.1 mg/l) were observed in 21.8% of the overweight subjects and 24.5% of the subjects with high (>85th percentile) % BF. After adjusting for age and gender, the odds ratios (95% CI) for elevated levels of CRP were 2.3 (1.1-4.7, P=0.02) for overweight subjects, 2.6 (1.2-5.4, P=0.01) for subjects with high % BF, and 3.7 (1.7-7.9, P=0.001) for subjects with high triceps skinfold thickness. Levels of CRP correlated significantly with % BF (r=0.13, P=0.009), W-HR (r=0.11, P=0.02), biceps skinfolds (r=0.13, P=0.01) and triceps skinfolds (r=0.13, P=0.01) for males only. CONCLUSIONS: The observations of substantial prevalence of elevated CRP levels in adolescents and young adults having increased generalized and abdominal adiposity may be important for the development of metabolic syndrome and atherosclerosis in Asian Indian adults.

Adipose Tissue↗
PubMed2003

Extensive dissection requiring multiple stents following balloon angioplasty for non-specific aorto-arteritis.

Discrete stenoses of the thoraco-abdominal aorta in non-specific aorto-arteritis are considered favorable lesions for balloon angioplasty characterized by good results without major complications. Herein, we describe one such case manifesting with severe hypertension, left ventricular dysfunction and congestive heart failure treated by angioplasty. Balloon dilatation, however, resulted in extensive dissection requiring implantation of two Wallstents. Over a follow-up of one year, hypertension remained under good control with fewer drugs and symptom relief was maintained. Left ventricular ejection fraction improved from 35% to 61%.

Adolescent↗
PubMed2003

Identification and management of ventricular tachycardia.

Recognising ventricular origin of a broad QRS tachycardia helps to appropriately identify and manage patients with ventricular tachycardia (VT) in the emergency. Relatively simple clinical and ECG clues help in reaching the correct diagnosis in the majority of patients. Management strategies vary with the clinical diagnosis and an implantable cardioverter defibrillator (ICD) is indicated for chronic prophylactic therapy in patients with coronary artery disease and serious ventricular arrhythmias, especially in those with ventricular dysfunction. The role of this device in patients with stable VT and ejection fractions > 0.35 deserves closer scrutiny. Radiofrequency ablation mostly plays an adjunctive role. Anti-arrhythmic drugs (amiodarone/sotalol and beta-blockers) are required to prevent frequent recurrences. A hybrid approach combining all these therapeutic modalities is often needed. Prognosis in patients with specific VT syndromes such as right ventricular outflow VT, left ventricular fascicular VT and left ventricular outflow VT is excellent with drugs. Radiofrequency ablation is curative in such syndromes.

Adrenergic beta-Antagonists↗
PubMed2001

Are drugs and catheter ablation effective for treating ventricular arrhythmias in populations that cannot afford implantable cardioverter defibrillators?

Despite recent advances, ventricular arrhythmias continue to pose a therapeutic challenge, especially to the clinician in the developing world. Although the implantable cardioverter defibrillator (ICD) has improved survival in both primary and secondary prevention trials, it still remains a costly modality for the developing world. Even though certain subgroups stand to benefit unequivocally in survival from the ICD, there are others in whom this therapy may not offer a survival benefit over empiric antiarrhythmic drug therapy with amiodarone. The utility of optimized drug therapy (including either amiodarone or sotalol, b-blockers, and angiotensin-converting enzyme inhibitors) needs to be compared with the ICD in a randomized manner in these lower-risk patients with ventricular arrhythmias. The role of conventional catheter ablation techniques is mostly adjunctive to drugs and ICDs, although the newer mapping and ablation techniques may offer greater promise in the future.

Arrhythmias, Cardiac↗
PubMed2001

Etiology and management of sustained ventricular tachycardia.

Ventricular tachyarrhythmias secondary to a variety of underlying cardiovascular problems pose a therapeutic challenge to the clinician. The initial presentation may be as sudden cardiac death, which underlies its public health problem. The underlying conditions predisposing to this arrhythmia include ischemic heart disease, dilated cardiomyopathy, hypertrophic cardiomyopathy, arrhythmiogenic right ventricle dysplasia and certain postoperative states including corrective surgery for tetralogy of Fallot and valve replacement. Other causes include prolonged QT syndrome, idiopathic right and left ventricle tachycardia and bundle branch re-entry tachycardia. Ischaemic heart disease is the most common cause of ventricular tachycardia and therapy has evolved considerably over the past two decades. The development of and refinements in the implantable cardioverter-defibrillator (ICD) have introduced a new dimension in therapeutic options and markedly improved survival in these patients. Insights in the dichotomy between arrhythmia suppression and total mortality have reoriented drug therapy with a decrease in the use of sodium channel blockers. beta-blockers have emerged as antiarrhythmic drugs in their own right and their synergistic effects with amiodarone have strengthened the antiarrhythmic drug arm. The role of these drugs in patients with hemodynamically stable ventricular tachycardia, especially in relatively preserved ventricles needs to be explored. Catheter ablation techniques have provided curative therapy in patients with idiopathic and bundle branch reentry tachycardia. Further advances in radiofrequency ablation, including use of newer mapping techniques, promise a greater role for ablation of ischemic ventricular tachycardia in the future. A hybrid approach consisting of drugs, catheter ablation and/ or ICD may provide effective therapeutic approach in some situations. Further innovations and technologic developments promise a further reorientation in therapy towards identification and treatment of the underlying arrhythmogenic substrate.

Adrenergic beta-Antagonists↗
PubMed2000

Clinical and echocardiographic predictors of left atrial clot and spontaneous echo contrast in patients with severe rheumatic mitral stenosis: a prospective study in 200 patients by transesophageal echocardiography.

The objective of this study was to prospectively investigate various clinical and echocardiographic variables to predict the left atrial and left atrial appendage clot and spontaneous echo contrast in patients with severe rheumatic mitral stenosis. We studied 200 consecutive patients (112 males and 88 females; mean age 29.6+/-9.6 years). Left atrial clot and spontaneous echo contrast were present in 26 and 53.5% of cases, respectively. There were no significant differences in the mitral valve area, mean transmitral diastolic gradient and left ventricular ejection fraction between patients with and without clot. Patients with clot were older (34.4+/-11.4 vs. 28.2+/-8.5 years, P<0.001), had longer duration of symptoms (41. 4+/-36.0 vs. 28.8+/-22.9 months, P<0.001), more frequent atrial fibrillation and spontaneous echo contrast (69.2 vs. 16.9%, P<0. 00001 and 76.9 vs. 45.3%, P<0.00001, respectively) and larger left atrial area and diameter (41.0+/-12.7 vs. 29.9+/-7.4 cm(2), P<0.00001 and 53.9+/-8.3 vs. 47.6+/-7.4 mm, P<0.0001, respectively) as compared to patients without clot. Similarly patients with spontaneous echo contrast were older (31+/-10.4 vs. 27.8+/-8.3 years, P<0.01), had more frequent atrial fibrillation (48.6 vs. 9.7%, P<0.0001), left atrial clot (37.4 vs. 12.9%, P<0.0001), larger left atrial area and diameter (37.6+/-11.2 vs. 28.1+/-6.7 cm(2), P<0.00001 and 52.2+/-8.3 vs. 45.9+/-6.5 mm, P<0.00001, respectively) and smaller mitral valve area (0.77+/-0.14 vs. 0.84+/-0.13 cm(2), P<0.01) as compared to patients without spontaneous echo contrast. There were no significant differences in the mean transmitral diastolic gradient and left ventricular ejection fraction. On multiple regression and discriminant function analysis, atrial fibrillation and left atrial area were independent predictors of left atrial clot formation. In a subgroup of patients with sinus rhythm, larger left atrial area and presence of spontaneous echo contrast were significantly associated with the presence of clot in left atrium and appendage. We conclude that in patients with severe mitral stenosis, the presence of atrial fibrillation and in the subgroup of the patients with sinus rhythm the presence of large left atrium (> or =40 cm(2)) and spontaneous echo contrast were associated with higher risk of clot formation in the left atrium and might be benefited by prophylactic anticoagulation.

Adolescent↗