Search PubMed⌕ Search

Biomedical subjects

S Shrivastava

Publications and source records attributed to S Shrivastava.

At least 37 records · Page 2Linked to original sources
PubMed2000

Non surgical closure of atrial septal defect using the Amplatzer septal occluder in children--feasibility and early results.

OBJECTIVE: To assess the feasibility and early results of Amplatzer septal occluder in children withy secundim atrial septal defect. SETTING: Tertiary care referral hospital in New Delhi. METHODS: Forty nine children under 12 years of age were diagnosed to be having fossa ovalis atrial septal defect. Forty nine patients underwent detailed 2D-Echocardiography and color Doppler interrogation for the possibility of non-surgical closure of ASD. Sixteen children between age 2.5-12 years (mean 6.5 years) were enrolled into the study. Their weight ranged from 10 kg to 42 kg and there were 9 males and 7 females. The remaining 33 were not considered suitable for device closure in echocardiography and were referred for surgery. RESULTS: All patients had more than 1.8 : 1 shunt. The device was successfully deployed in 13/16 patients. ASD stretched diameter ranged between 13 mm-30 mm (mean 15 mm) and the device size ranged between 14 mm-22 mm. One patient had fenestrated ASD, in this patient the largest of the defect was crossed and closed with 24 mm device resulting in closure of all three defects. We failed in three of our attempts, on one there were deficient inferior margins while in the other two cases the ASD stretched size was such that the device would have encroached upon adjacent structures, hence the procedure was abandoned. All these patients have been operated successfully. Complete abolition of shunt was seen in 38% patients in the immediate post deployment period. At 24 hours complete closure was seen in 12/13 (92%) patients while one patient had trivial residual shunting across the device. This patient also achieved complete closure of atrial shunting when evaluated at three months follow-up. CONCLUSION: Device closure of ASD is emerging as an alternative to surgical closure. However, with the currently available device only a limited number of atrial septal defects can be closed. Long-term studies are required to show sustained benefits and absence of side effects of this device.

Adolescent↗
PubMed2000

Transcatheter closure of patent ductus arteriosus.

OBJECTIVE: To present short and intermediate results of catheter closure of patent ductus artereiosus using spring coils and Amplatzer duct occluder. SETTING: Tertiary care referral hospital in New Delhi. METHOD: 121 patients were diagnosed to be having patency of the arterial duct between October 1996 and December 1999. Their ages ranged between 4 mo and 480 mo (mean 80.5 mo). Before August 1998 only spring coils were used as an alternative to surgical closure of the duct, whereas between August 1998 and December 1999 both coils and device were used. RESULTS: Spring coils were attempted in 48, Amplatzer duct occluder in 44 and 29 patients were referred for surgery. Coils were successfully deployed in 42/48 (87.5%) and device in 42/44 (95.5%) patients. Complete closure of the arterial duct was seen in 96% patients in the coil closure group at the end of one year and 100% closure was achieved in the device closure group at the end of 3 months in all the patients followed. Coil embolised in 11 patients, significant stenosis of left pulmonary occurred in one patient and severe hemolysis requiring blood transfusion occurred in one patient after coil closure. Six patients required a second procedure to close the residual shunt within 6 months of the initial coil deployment. One patient had loss of femoral artery pulses in right leg after device closure and required heparin infusion for 48 hours. There were 8 failed attempts. All these patients have been operated successfully. CONCLUSION: Percutaneous closure of the patent ductus arteriosus using Coils or the Amplatzer device is an acceptable method. Small residual shunts are common after the initial procedure especially after coil deployment but most close spontaneously.

Adolescent↗
PubMed2000

Timing of surgery/catheter intervention in common congenital cardiac defects.

A large load of children with congenital heart disease (CHD) exists in our country. Fortunately facilities for treatment of almost all types of defects are available, although in few centres only. Many children are however, referred late for correction making them either high risk for surgery or inoperable due to development of irreversible pulmonary vascular obstructive disease. Therefore, it is important to recognise the ideal time of intervention in different types of CHD. A child with large atrial septal defect should have its closure by 3 to 4 years of age; on the other hand, a large ventricular septal defect (VSD) producing congestive heart failure needs very early surgery. Infants with small VSD may be medically managed as chances of spontaneous closure are high. Ligation of patent ductus arteriosus should be done at about one year of age if there is no pulmonary arterial hypertension or congestive heart failure. Similarly, coarctation should be dealt with either balloon dilatation or surgery at about one year of age provided the left ventricular function is normal and blood pressure in upper limb is well under control. For tetralogy of Fallot, correction is best done at about 9 months to one year of age. In case the child is symptomatic early, either a palliative shunt is done or total correction is performed if anatomy is suitable. In admixture lesions like transposition of great arteries (TGA), persistent truncus arteriosus or total anomalous pulmonary venous drainage, a very early intervention is needed so as to avoid development of severe hypoxia and early pulmonary vascular obstructive changes. Arterial switch operation is best performed in first two to three weeks of life for TGA with intact ventricular septum cases. Knowledge of natural history of the CHD is essential to plan for optimal timing of surgery or catheter intervention.

Cardiac Catheterization↗
PubMed1999

Juvenile tricuspid stenosis and rheumatic tricuspid valve disease: an echocardiographic study.

Tricuspid valve involvement is not uncommon in patients with rheumatic heart disease and is frequently missed on routine clinical examination. We prospectively studied the echocardiographic profile of tricuspid valve disease in 788 consecutive patients with rheumatic heart disease. Out of these patients 9% (70) had tricuspid valve disease and 55.7% (39) of these were of < or = 20 years of age. Of these 60% were females and 40% were males. Their ages ranged from 9 to 64 years (mean 24.2+/-13.6 years). Of these patients, 50% had tricuspid stenosis with or without tricuspid regurgitation whereas 50% had isolated tricuspid regurgitation. Isolated tricuspid stenosis was present in 7.4% of these cases. All patients had associated mitral stenosis. Severe mitral stenosis was present more commonly in patients with juvenile tricuspid stenosis compared to older patients (94.1% vs. 55.6%, P<0.005). Mitral regurgitation was present more commonly in juvenile age group patients compared to older patients (53.8% vs. 25.8%, P<0.01). A combination of mitral, aortic and tricuspid stenosis was present in five cases and four of these were in the juvenile age group. Left ventricular enlargement and dysfunction were present in 28.6 and 14.3% patients, respectively, and the majority of these patients were in the juvenile age group (P<0.05). We conclude that rheumatic tricuspid valve disease occurs early in the course of the disease and progresses faster in India and is always associated with mitral stenosis. Juvenile tricuspid stenosis is more commonly associated with severe mitral stenosis, mitral regurgitation, left ventricular enlargement and dysfunction as compared with older patients.

Adolescent↗
PubMed1999

Percutaneous balloon mitral valvuloplasty using the Inoue balloon: analysis of echocardiographic and other variables related to immediate outcome.

To determine whether the mitral valve morphology influences the results of percutaneous balloon mitral valvuloplasty for mitral stenosis, two-dimensional echocardiography was performed before valvuloplasty in 126 patients (mean age 25.5+/-9.4 years) and in 30 normal controls. The 2D echocardiographic features of mitral valve leaflets: thickness, length and motion; diastolic mitral valvular excursion; chordal length; mitral annular diameter; subvalvular distance ratio; distance between mid mitral annulus to left ventricular apex, base and tip of papillary muscle and effective balloon dilating area, effective balloon dilating area/body surface area and effective balloon dilating diameter/mitral annular diameter were then correlated to the immediate post-valvuloplasty mitral valve area. For the total patients population, post-valvuloplasty valve area increased from 0.67+/-0.17 to 2.1+/-0.86 cm2 (P<0.0001), mean transmitral diastolic gradient decreased from 24.5+/-9.0 to 6.0+/-3.0 mm Hg (P<0.0001), mean left atrial pressure decreased from 29.7+/-6.2 to 12.7+/-4.8 mm Hg (P<0.0001), mean pulmonary artery pressure decreased from 44.8+/-14.2 to 25.4+/-9.5 mm Hg (P<0.0001) and cardiac index increased from 2.7+/-0.38 to 3.1+/-0.55 l/min/m2 (P<0.0001). The patients were divided into three groups on the basis of post-valvuloplasty mitral valve area. Group I had valve area <1.5 cm2, group II had valve area from 1.5 to 1.9 cm2 and group III had valve area > or =2.0 cm2. On comparison, no statistically significant difference was found in any of the echocardiographic variables in the three groups. On univariate, multivariate, multiple regression and discriminate function analysis, none of the variables were found to have significant influence on immediate result of valvuloplasty. There was no significant difference in the incidence of mitral regurgitation in any of the three groups. We conclude that the extent of mitral valvular and subvalvular deformity do not have a significant effect on the immediate outcome of mitral valvuloplasty using the Inoue balloon and it can be successfully performed in patients with severe subvalvular fibrosis. Unique balloon geometry and stepwise balloon sizing may explain these acceptable immediate results in severely deformed valves.

Adult↗
PubMed1999

Significant intraoperative right ventricular outflow gradients after repair for tetralogy of Fallot: to revise or not to revise?

BACKGROUND: This study was performed to define alternative parameters for the management of intraoperative residual right ventricular outflow obstruction (RVOTO) after transatrial repair of tetralogy of Fallot (ToF) in order to differentiate those requiring immediate revision from those who do not. METHODS: Since October 1995, 166 patients of ToF underwent transatrial repair. Postbypass residual RVOTO was assessed by surgeon's subjective impression, direct intracardiac pressure measurements, and intraoperative echocardiography (IOE). RVOTO was labeled "significant" whenever it exceeded a gradient of 40 mm Hg on IOE or right ventricular to left ventricular pressure ratio (pRV/LV) exceeded 0.85. Further, on IOE, significant RVOTO was defined "fixed", if there was no change in RVOT dimensions during the cardiac cycle, along with the presence of anatomic substrate for obstruction, and "dynamic" if RVOT dimensions increased appreciably in diastole. Postoperative course and follow-up echocardiograms of all patients were analyzed. RESULTS: Significant RVOTO was detected in 58 (35%) patients (mean gradient 54 mm Hg). Seven (12%) of them with fixed obstruction (mean 46 mm Hg) underwent immediate surgical revision, while the remaining 51 patients with mean gradient of 78 mm Hg (including 10 patients with pRV/LV ratio of > or = 1.0) with dynamic obstruction did not undergo revision. There were six (3.6%) early deaths. Operative mortality and postoperative morbidity were not related to higher residual gradients, although the first 15 such patients had longer intensive care stay and inotropic support, in which this was done electively. On follow-up (mean 18.5 months), outflow gradients declined sharply (mean 16 mm Hg) irrespective of the severity of intraoperative gradients (p < 0.001). There were no reoperations or late deaths. CONCLUSIONS: This study shows that: 1) existing parameters for immediate revision of residual RVOTO possibly need to be reviewed; 2) intraoperative echocardiography helps in differentiating "fixed" from "dynamic" obstruction and helps obviate needless revisions; and 3) dynamic RVOT gradients decline significantly irrespective of their severity after transatrial repair of ToF.

Adolescent↗
PubMed1998

Cross-sectional and Doppler echocardiographic diagnosis of anomalous origin of the left coronary artery from the pulmonary artery and right coronary artery from posterior aortic sinus.

A six-year-old asymptomatic child on evaluation for a cardiac murmur, was found on cross-sectional and Doppler echocardiography to have an anomalous origin of the left coronary artery from the pulmonary artery and right coronary artery from posterior sinus of aorta. Doppler studies revealed a continuous signal in the pulmonary artery, indicating a left to right flow. The diagnosis was subsequently confirmed at cardiac catheterization and surgery.

Child↗
PubMed1998

Cardiac myxomas: clinical and echocardiographic profile.

We reviewed our clinical and echocardiographic experience in 70 consecutive patients with 73 cardiac myxomas, diagnosed over an 11 year period. There were 21 males and 49 females, ages ranged from 18 to 80 years. Only in 5.7% cases was the diagnosis of myxomas made clinically. 88.6% cases were initially diagnosed as having: mitral valve disease (70%), tricuspid valve disease (10%), ischemic heart disease (5.7%), cardiomyopathy (2.9%), and the remaining 5.7% were detected during family screening and follow-up. The mean duration of symptoms was 10.6 months. The commonest symptom was dyspnoea (80%), followed by constitutional symptoms (45.7%), embolization (30%), palpitation (25.7%), syncope (15.7%), pedal oedema (15.7%) and pain chest (12.9%). The sites of myxomas were as follows: left atrium, 58; right atrium, 9; and, biatrium, 3. All myxomas except 3 were attached to the interatrial septum. The site, size, shape, attachment, mobility, prolapse into ventricle, and surface characteristic of myxomas were accurately assessed by 2D-echocardiography and confirmed in all (65 of 70) who underwent surgery. When the morphological characteristic of myxomas were studied and correlated with clinical features large left atrial myxoma size was closely related with constitutional symptoms, congestive heart failure, with syncope and auscultatory findings suggestive of mitral valve disease, whereas smaller myxoma size and irregular surface were associated with embolization. Constitutional symptoms were only present in left atrial myxoma. Post-operative mean echocardiographic follow-up of 60 months showed no recurrence except in 2 with familial myxoma. We conclude that the majority of myxomas mimic many cardiovascular diseases and were detected in symptomatic patients, so a high index of clinical suspicion is important for its early and correct diagnosis. The size and appearance of the myxomas correlated with the presenting symptoms.

Adolescent↗
PubMed1997

Immediate and follow up results of Inoue balloon mitral valvotomy in juvenile rheumatic mitral stenosis.

BACKGROUND AND AIMS OF THE STUDY: Juvenile rheumatic mitral stenosis (MS) with severe pulmonary venous and arterial hypertension (PAH) is a relatively common occurrence in developing countries. The study objectives were to evaluate the safety, efficacy and follow up of Inoue balloon mitral valvotomy (IBMV) in juveniles with rheumatic MS. METHODS: A total of 193 patients with juvenile rheumatic MS were analyzed and compared with adults, with specific reference to the effect of IBMV on hemodynamics and pulmonary vasculature in patients with severe PAH. RESULTS: Mitral valve areas were smaller (0.76 +/- 0.22 versus 0.81 +/- 0.22 cm2), while mean pulmonary arterial pressure (MPAP) (44.5 +/- 16.5 versus 38.4 +/- 15.1 mmHg) and pulmonary vascular resistance (PVR) (5.5 +/- 4.6 versus 4.41 +/- 4.04 Wood units) were greater in juvenile patients when compared with adults. There was a 99% procedural success. Juvenile patients showed an overall greater fall in MPAP and PVR when compared with adults. The incidence of severe PAH was much higher (32%) among juveniles than adults (16%). Only 5% of patients with juvenile MS with severe PAH had residual severe PAH immediately after IBMV, compared with 17% in older patients. Hemodynamic benefits (echocardiographic mean transvalvular gradient and mitral valve area) were sustained at a mean follow up of 29 months, and there was no documented case of restenosis after successful IBMV. CONCLUSIONS: We conclude that IBMV is safe and effective in juvenile rheumatic MS and provides greater hemodynamic benefit compared with adults; such benefit is sustained during a mean follow up of 29 months.

Adolescent↗
PubMed1996

Transesophageal dobutamine-atropine stress echocardiography: diagnostic accuracy for coronary stenosis detection and localization.

Transesophageal echocardiography with dobutamine-atropine stress (TE-DASE) is a recently described technique for evaluation of coronary artery disease (CAD). We undertook this study prospectively to determine the feasibility, reliability and safety of this procedure in patients with known CAD and to evaluate its diagnostic accuracy for coronary stenoses of varying severity. Thirty-seven patients who underwent coronary arteriography (CART) and TE-DASE within a 3-month interval without intervening ischemic events or revascularisation were included in the study CART and stress echograms were independently evaluated by different observers. Stenosis was measured with calipers and a > or = 50% lumen diameter stenosis was considered significant. A reduction or lack of endocardial motion and/or wall thickening on progressive incremental stress was considered an abnormal response. TE-DASE could be successfully completed in 33/37 (90%) patients. Using a modified 16-segment model of the left ventricle (LV), 15.2 +/- 0.8 segments/patient and 501/528 (95%) segments overall could be optimally evaluated. Inter-observer concordance for an abnormal response was 94%. Predictive accuracies for one-vessel disease (1-VD), two-vessel disease (2-VD) and three-vessel disease (3-VD) were 88, 58 and 23% respectively. Overall sensitivity for detection of a significant (> or = 50%) stenosis was 72% (32% for moderate (50-69%), 90% for severe (> or = 70%) stenosis) and specificity was 96%. Diagnostic accuracy for localisation of significant stenosis was 95% for the left anterior descending artery (LAD), 86% for the left circumflex artery (LCX) and 88% for the right coronary artery (RCA). There were no major complications. We conclude that TE-DASE is a safe, reliable and easily-performed procedure and provides excellent visualisation of myocardial segments. Diagnostic accuracy for detection of severe stenosis and its localisation is excellent.

Atropine↗
PubMed1996

Echocardiographic evaluation of patients with acute rheumatic fever and rheumatic carditis.

BACKGROUND: Cardiac involvement is the most important component of acute rheumatic fever. The role of echocardiography in the evaluation of rheumatic carditis has not been adequately defined. We used echocardiography in a large sample of patients with acute rheumatic fever to describe morphological abnormalities associated with rheumatic carditis and to assess its role in the diagnosis of rheumatic carditis. METHODS AND RESULTS: Cross-sectional and color Doppler echocardiographic examination was performed in 108 consecutive patients with acute rheumatic fever within 24 to 48 hours of diagnosis. Twenty-eight patients had acute rheumatic fever without clinical evidence of carditis (group 1). Thirty-five patients had a presumed first episode of rheumatic carditis (group 2), and 45 patients had a recurrence of carditis (group 3). Patients in group 1 did not demonstrate any evidence of valvular regurgitation. Mitral regurgitation was the most common Doppler echocardiographic feature in groups 2 (94%) and 3 (84%). Valvular thickening with or without restriction of leaflet mobility was frequently seen in rheumatic carditis. One of every 4 patients with rheumatic carditis demonstrated echocardiographic presence of focal valvular nodules. These nodules were found on the body and the tips of the mitral valve leaflets and disappeared on follow-up. Ventricular dilatation (group 2, 54%; group 3, 74%) and restriction of leaflet mobility (group 3, 37%) were common mechanisms of mitral regurgitation in rheumatic carditis; valve prolapse (group 2, 9%; group 3, 16%) and annular dilatation (group 2, 12%; group 3, 21%) were infrequent. The majority of patients with rheumatic carditis had normal left ventricular systolic function. Congestive heart failure (group 2, 17%; group 3, 40%) was invariably associated with the presence of hemodynamically significant valve lesions. On follow-up, no patient in group 1 developed valvular regurgitation. In group 2 patients, a progressive decrease in left ventricular dimensions was observed without any change in ventricular fractional shortening. Valvular regurgitation remained unchanged in 69% of patients, decreased in 22%, and disappeared in 9%. CONCLUSIONS: In patients with rheumatic carditis, the mitral valve is most often involved and mitral regurgitation is the most common finding on color flow imaging. Mitral regurgitation in rheumatic carditis is related to ventricular dilatation and/or restriction of leaflet mobility. Rheumatic carditis does not result in congestive heart failure in the absence of hemodynamically significant valve lesions. In a quarter of patients with rheumatic carditis, we observed valve nodules that may represent echocardiographic equivalents of rheumatic verrucae. Our study failed to reveal any incremental diagnostic utility of echocardiography and Doppler color flow imaging in rheumatic fever without clinical evidence of carditis.

Acute Disease↗
PubMed1996

Use of dopamine in prevention of contrast induced acute renal failure--a randomised study.

We report the use of dopamine in renal doses (5 micrograms/kg/min) to prevent contrast induced nephropathy (CIN). Forty patients with diabetes mellitus who were undergoing coronary angiography were randomly divided into two groups. Gr I (20 patients) was infused with dopamine starting 30 min before cardiac catheterization and continued for 6 h thereafter. Gr II (20 patients) did not receive dopamine. Baseline blood chemistry was performed before catheterization and then repeated 24 h after the procedure. The mean age and sex distribution were similar in both the groups. Urograffin (76%; 120-150 ml) was used in all the cases. The mean serum creatinine and blood urea nitrogen (BUN) levels in Gr I patients before catheterization were 1.5 +/- 0.32 mg % and 16.3 +/- 8.05 mg %, respectively. The corresponding values for Gr II were 1.52 +/- 0.68 mg % and 19.6 +/- 13.4 mg %, respectively. After angiography, Gr I patients did not show significant changes in renal parameters (serum creatinine, 1.37 +/- 0.25 mg % and BUN, 14.7 +/- 5.5 mg %) while Gr II patients showed a significant rise (serum creatinine, 1.96 +/- 1.2 mg % and BUN, 23.25 +/- 12.7 mg %; P = 0.01 and P = 0.05, respectively). Ten patients in Gr II (50%) developed a 25% rise in serum creatinine levels within 24 h of injection of the contrast. None of the patients developed renal failure severe enough to warrant dialysis. Hence alterations of renal function are common after cardiac catheterization. Dopamine in renal doses appears to be an effective means to prevent deterioration in renal function induced by contrast.

Acute Kidney Injury↗