Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Paramjeet S. Chopra is active.

Publication


Featured researches published by Paramjeet S. Chopra.


American Journal of Cardiology | 1996

Transcatheter closure of atrial septal defect or patent foramen ovale with the buttoned device for prevention of recurrence of paradoxic embolism

David J. Ende; Paramjeet S. Chopra; P. Syamasundar Rao

Transcatheter occlusion of patent foramina ovalia and atrial septal defects in 10 patients with presumptive paradoxic embolic stroke using the buttoned device appears to be encouraging, with safety and efficacy demonstrated during a follow-up of up to 60 months. Anticoagulation should be continued until complete disappearance of the right-to-left atrial shunt.


The Annals of Thoracic Surgery | 1991

Role of balloon angioplasty in the treatment of aortic coarctation

P. Syamasundar Rao; Paramjeet S. Chopra

Since the initial report of coarctation balloon angioplasty in 1982, several groups have used this technique for native coarctations in neonates, infants, and children and for postoperative recoarctations. However, recommendations for use of balloon angioplasty as a treatment procedure of choice are clouded by reports of aneurysm development at the site of coarctation. Here we review our experience as well as that published in the literature, including Valvuloplasty and Angioplasty of Congenital Anomalies Registry data, and present evidence in support of balloon angioplasty as a therapeutic procedure of choice for treating native and recurrent postoperative aortic coarctations. Balloon angioplasty of native aortic coarctations in 20 neonates and infants 1 year old or less reduced peak systolic pressure gradient across the coarctation from 40 +/- 12 mm Hg (mean +/- standard deviation) to 11 +/- 8 mm Hg (p less than 0.001); no patient required immediate surgical intervention. The residual gradient at follow-up (mean follow-up, 12 months) in 16 infants was 18 +/- 16 mm Hg, a significant improvement (p less than 0.01) compared with preangioplasty values. In none of the patients did an aneurysm develop. Recoarctation developed in 5 (31%) of the 16 infants and was successfully treated either by surgical resection (in 2) or by repeat balloon angioplasty (in 3). A comparison of mortality and recurrence rates between the balloon angioplasty and surgical groups was made with the help of data pooled from the literature published since 1980. The initial (7% versus 23%) and late (2% versus 25%) mortality and recoarctation (11% versus 18%) rates were higher (p less than 0.025) after surgical intervention than after balloon therapy. When only reports in which patients were operated on after 1979 were included in this type of analysis, the initial and late mortality rates remained higher (p less than 0.01) after operation than after angioplasty, and the recoarctation rates became similar (p greater than 0.1). Thirty-two children (greater than 1 year old) underwent balloon angioplasty of native coarctation with a resultant reduction in peak systolic pressure gradient from 48 +/- 19 mm Hg to 10 +/- 9 mm Hg (p less than 0.001), which continued to remain low (14 +/- 11 mm Hg; p less than 0.001) at follow-up catheterization in 24 children 13 months (mean) later. There were no immediate or late deaths. A small aneurysm developed in 1 patient (4%) but did not require intervention. Recoarctation developed in 2 patients (8%), and in both, repeat balloon angioplasty was performed with good results.(ABSTRACT TRUNCATED AT 400 WORDS)


Journal of the American College of Cardiology | 1994

Surgical versus balloon therapy for aortic coarctation in infants ≤ 3 months old☆

P. Syamasundar Rao; Paramjeet S. Chopra; Rebecca L. Koscik; Patricia A. Smith; Allen D. Wilson

OBJECTIVES This study compared the efficacy and safety of balloon angioplasty with surgical correction of native aortic coarctation in infants < or = 3 months old. BACKGROUND There is a controversy with regard to the role of balloon angioplasty in the treatment of aortic coarctation, especially in young infants. METHODS Data from 29 infants < or = 3 months old undergoing therapy for aortic coarctation during the decade ending 1992 were analyzed. Fourteen infants underwent surgery, and 15 had balloon angioplasty. The sole criterion for allotment to the balloon group was the availability of an interventional cardiologist at the time of presentation of the infant. RESULTS The surgical and balloon groups were comparable (p > 0.1) with regard to age (27 +/- 35 [mean +/- SD] vs. 29 +/- 27 days), weight (3.5 +/- 0.9 vs. 3.8 +/- 1.0 kg) and prevalence (7 of 14 vs. 8 of 15) and type of associated defects. Operative (1 of 14 vs. 1 of 15) and late (3 of 13 vs. 3 of 14) mortality, immediate gradient relief (36 +/- 25 to 10 +/- 9 mm Hg vs. 41 +/- 14 to 6 +/- 6 mm Hg) and follow-up gradient (27 +/- 27 vs. 24 +/- 19 mm Hg) were similar (p > 0.1). Infants with a gradient > 20 mm Hg at follow-up (6 of 13 vs. 7 of 14) and need for reintervention (6 of 13 vs. 7 of 14) were also similar (p > 0.1) in both groups. Duration of hospital stay during the first intervention was higher (p < 0.05) in the surgical (32 +/- 37 days) than the balloon (7 +/- 6 days) group. Similarly, duration of endotracheal intubation and mechanical ventilation was longer (p < 0.05) in the surgical (12 +/- 16 days) than the balloon (2 +/- 3 days) group. Complications after surgical intervention (0.86 events/patient) were higher (p < 0.01) than those seen after balloon angioplasty (0.27 events/patient). However, the lack of significant differences observed for mortality rates and residual gradients may be due to low statistical power to detect differences (16% to 49%), implying that this may be due to either actual lack of statistical difference or small sample size. CONCLUSIONS The data indicate that the degree of relief from aortic coarctation and the frequency with which reintervention is needed are similar in both groups. However, the morbidity and complication rates are lower with balloon than with surgical therapy. These data suggest that balloon angioplasty may be an acceptable alternative to surgical correction in the treatment of symptomatic aortic coarctation in infants < or = 3 months old.


American Heart Journal | 1992

Role of buttoned double-disc device in the management of atrial septal defects

P. Syamasundar Rao; Allen D. Wilson; Jay M. Levy; Vinod K. Gupta; Paramjeet S. Chopra

Abstract Sixteen patients seen over a 9-month period ending in August 1990 were offered transcatheter closure of their ASD with a custom-made “buttoned” double-disc device. The study was approved by the Institutional Review Board and informed consent was obtained in each case. The device consists of an occluder, a counteroccluder, and a loading wire and is delivered to the ASD site via an 8F sheath. Parents of two children elected surgical closure. In five children the stretched diameter of the ASD was too large (>20 mm) and transcatheter closure was not attempted. These seven children underwent elective surgical closure without incident. In one child the defect measured 5 mm and the Qp:Qs was 1.4:1 and therefore ASD closure was not recommended. In the remaining eight children transcatheter closure was attempted. In two of the children the occluder pulled through the ASD and was successfully retrieved and the children later underwent uneventful elective surgical closure. The device was implanted across the ASD in six children. In one child the device dislodged from the ASD site within minutes after implantation and the child was sent to emergency surgery, where the device was removed and the ASD was closed. In the remaining five patients, aged 7 months to 45 years (weight 3.6 to 50 kg), with a Qp:Qs range of 1.3 to 2.3 and a stretched diameter of 10 to 19 mm, the ASD closure was successful with 25 to 40 mm size devices. Repeat echo-Doppler studies 2 weeks and 3 months after the procedure in all patients and 6 months later in two children did not reveal any residual shunt. It is concluded that (1) the custom-made “buttoned” double-disc device can be implanted across the ASD safely and effectively via an 8F sheath, thus making transcatheter ASD closure feasible even in very young infants; (2) measurement of stretched diameter of the ASD in the catheterization laboratory is a useful guide for selection of an appropriate-sized device; and (3) additional clinical trials are warranted to confirm the efficacy and safety of the device.


American Heart Journal | 1990

Immediate and follow-up results of balloon angioplasty of postoperative recoarctation in infants and children

P. Syamasundar Rao; Allen D. Wilson; Paramjeet S. Chopra

The purpose of this article is to present immediate and follow-up results of balloon angioplasty of aortic recoarctations following previous surgery in infants and children. During a 45-month period that ended in June 1989, nine infants and children, ages 6 months to 7 years, underwent balloon angioplasty of recoarctation with resultant reduction in peak-to-peak systolic pressure gradient from 52 +/- 20 mm Hg (mean +/- SD) to 16 +/- 8 mm Hg (p less than 0.001) and increase in coarctation segment size from 3.4 +/- 1.4 mm to 6.1 +/- 1.6 mm (p less than 0.01). None required surgical intervention. There were no significant complications. Follow-up catheterization (16 +/- 7 months) data in six children and follow-up clinical (17 +/- 6 months) data in all children were available for review. Both the residual coarctation pressure gradient (6 +/- 6 mm Hg) and coarctation segment size (8.2 +/- 2.4 mm) remain improved (p less than 0.001) when compared with pre-balloon angioplasty values and the pressure gradient fell further (p less than 0.01) when compared with that measured immediately after balloon angioplasty. None developed restenosis, although one child required surgical relief of severe narrowing of isthmus of the aortic arch. None developed aneurysms. On the basis of this experience and that reported in the literature and because of high morbidity and mortality rates associated with repeat surgery for postoperative recoarctation, we recommend balloon angioplasty as the procedure of choice for relief of postoperative recoarctation with significant hypertension.


American Journal of Cardiology | 1989

Intermediate-term follow-up results of balloon aortic valvuloplasty in infants and children with special reference to causes of restenosis

P. Syamasundar Rao; Mohinder K. Thapar; Allen D. Wilson; Jay M. Levy; Paramjeet S. Chopra

Sixteen infants and children with valvular aortic stenosis underwent percutaneous balloon aortic valvuloplasty over a 36-month period ending August 1988. The mean systolic pressure gradient across the aortic valve decreased from 72 +/- 21 (mean +/- standard deviation) to 28 +/- 13 mm Hg (p less than 0.001) immediately after valvuloplasty; the degree of aortic insufficiency did not significantly increase. Follow-up catheterization (in 10 patients) and Doppler data (in all 16 patients) were available 3 to 32 months (mean 12 months) after valvuloplasty and revealed a residual aortic valvular gradient of 37 +/- 23 mm Hg, which continues to be significantly lower (p less than 0.001) than that before valvuloplasty. There was no increase in aortic insufficiency. On the basis of follow-up data, the 16 children were divided into 2 groups: group I with good results (gradients less than or equal to 49 mm Hg), 12 patients; and group II with poor results (gradients greater than or equal to 50 mm Hg), 4 patients. All 4 patients in group II required repeat balloon valvuloplasty or surgical valvotomy; none from group I required these procedures. Seventeen general, anatomic, physiologic and technical variables were examined by a multivariate logistic regression analysis to identify factors associated with restenosis; these risk factors were: age less than or equal to 3 years; and immediate aortic valvular gradient after valvuloplasty greater than or equal to 30 mm Hg. The immediate and intermediate-term follow-up results of balloon aortic valvuloplasty are encouraging. Recognition of the risk factors may help identify potential candidates for recurrence.(ABSTRACT TRUNCATED AT 250 WORDS)


American Heart Journal | 1990

Balloon angioplasty of stenosed Blalock-Taussig anastomosis: Role of balloon-on-a-wire in dilating occluded shunts

P. Syamasundar Rao; Jay M. Levy; Paramjeet S. Chopra

Six children with cyanotic congenital heart defects, aged 6 to 60 months, underwent percutaneous balloon angioplasty of a narrowed Blalock-Taussig (BT) shunt to improve arterial oxygen saturation. The indication for angioplasty was a cyanotic heart defect not amenable to total surgical correction, either because of the age and size at presentation or because of anatomic complexity, but at the same time requiring palliation of pulmonary oligemia. Following balloon angioplasty, there was an increase in arterial oxygen saturation from 71 +/- 8% to 81 +/- 6% (p less than 0.05). In one child with long segment narrowing, there was no significant improvement in oxygen saturation, and this child underwent an additional BT shunt on the contralateral side. On follow-up 3 to 12 months after balloon angioplasty, the oxygen saturations remained improved (78 +/- 10%) in the remaining five patients. In two children with either complete or almost complete blockage of the BT shunt, we were unable to advance any catheter across the shunt but we were able to advance a 2 or 3 mm balloon on a wire and dilate the shunt, followed by introduction of a catheter carrying a larger balloon for angioplasty. This has permitted us to obtain the pulmonary artery pressure directly (this information was of obvious value in patient management) and resulted in an improvement in the arterial oxygen saturation. It is concluded that (1) balloon angioplasty of narrowed BT shunts is feasible, effective, and safe and (2) even completely occluded shunts can be cannulated and the balloon dilated with the newly available balloon-on-wire devices.


American Heart Journal | 1992

Corrective surgery for tricuspid atresia : which modification of Fontan-Kreutzer procedure should be used ? A review

Paramjeet S. Chopra; P. Syamasundar Rao

Various modifications of Fontan-Kreutzer procedure have evolved over the years. The available literature was reviewed in an attempt to evaluate whether one of these operations is preferable to others. Although there is no complete agreement, direct atriopulmonary anastomosis in the absence of a subpulmonary ventricular chamber, and atrioventricular connection via a homograft conduit in patients with a good-sized (greater than 30% of normal), well-formed (with both trabecular and outlet portions) right ventricle appear to be reasonable choices. In patients with more than the usual risk or at low risk for the Fontan-Kreutzer procedure, other alternatives (namely, total cavopulmonary connection for patients with asplenia/polysplenia syndrome and systemic venous anomalies and bidirectional cavopulmonary anastomosis or Fontan-Kreutzer with a small temporary atrial septal defect) could be considered. The role of experimental skeletal muscle augmentation or replacement of right heart chambers and cardiac transplantation in the corrective treatment of tricuspid atresia needs to be defined as more data become available.


American Heart Journal | 1997

Aneurysm of the membranous ventricular septum resulting in pulmonary outflow tract obstruction in congenitally corrected transposition of the great arteries

S. Chandra Bose Reddy; Paramjeet S. Chopra; P. Syamasundar Rao

Aneurysm of the membranous ventricular septum causing subpulmonic obstruction in patients with corrected transposition is rare but well documented. Higher left-sided (morphologic right) ventricular pressure causes protrusion of the aneurysm into the pulmonary outflow tract of the right-sided morphologic left ventricle, causing obstruction related to lack of conus and proximity of the aneurysm to subpulmonary region. Echo Doppler studies and angiography are useful in making a correct diagnosis. Surgical resection of the aneurysm along with closure of the ventricular septal defect is the treatment of choice. The prognosis is likely to be excellent.


The Annals of Thoracic Surgery | 1987

The Blalock-Hanlon Operation: An Anachronism?

David J. Cohen; Paramjeet S. Chopra

Some surgeons advocate early correction of dextrotransposition of the great arteries (D-TGA) using hypothermic circulatory arrest when Rashkind balloon atrial septostomy is inadequate. An alternative procedure is a Blalock-Hanlon closed atrial septectomy. From 1971 to 1985, 19 patients underwent the latter procedure for D-TGA at our institution. Three had it as the first procedure, and 16 had undergone Rashkind balloon atrial septostomy, which was unsuccessful. Age at performance of the Blalock-Hanlon closed atrial septectomy ranged from 1 day to 5 months (mean, 2.51 months). There were no operative deaths. Subsequently, 18 children have had a Mustard procedure, and 1, a Rastelli procedure (average age at definitive repair, 25.31 months). One death followed definitive repair (combined mortality, 5%). On room air, average partial pressure of arterial oxygen rose from 23.25 mm Hg prior to closed atrial septectomy to 31.45 mm Hg at discharge. Average hematocrit fell from 58.37% prior to closed atrial septectomy to 53.94% prior to definitive repair. At the time of definitive repair, percentile height ranged from the 3rd to the 95th percentile (mean, 44th percentile) and weight ranged from the 3rd to the 90th percentile (mean, 32.5th percentile). In 1 infant, transient neurological symptoms developed three days following Blalock-Hanlon atrial septectomy. The symptoms were due to multiple cerebral infarctions thought to be caused by emboli. No permanent neurological deficit resulted. We believe that the infant with an inadequate Rashkind balloon atrial septostomy prior to age 6 months should undergo a Blalock-Hanlon septectomy followed by definitive repair timed on the basis of the babys growth, associated anomalies, and evidence of pulmonary hypertension.

Collaboration


Dive into the Paramjeet S. Chopra's collaboration.

Top Co-Authors

Avatar

P. Syamasundar Rao

University of Texas Health Science Center at Houston

View shared research outputs
Top Co-Authors

Avatar

Allen D. Wilson

University of Wisconsin-Madison

View shared research outputs
Top Co-Authors

Avatar

Jay M. Levy

University of Wisconsin-Madison

View shared research outputs
Top Co-Authors

Avatar

Donald R. Kahn

University of Wisconsin-Madison

View shared research outputs
Top Co-Authors

Avatar

Herbert A. Berkoff

University of Wisconsin-Madison

View shared research outputs
Top Co-Authors

Avatar

George M. Kroncke

University of Wisconsin-Madison

View shared research outputs
Top Co-Authors

Avatar

William P. Young

University of Wisconsin-Madison

View shared research outputs
Top Co-Authors

Avatar

Eleftherios B. Sideris

University of Wisconsin-Madison

View shared research outputs
Top Co-Authors

Avatar

Guillermo C. Dacumos

University of Wisconsin-Madison

View shared research outputs
Top Co-Authors

Avatar

Alejandro Munoz

University of Wisconsin-Madison

View shared research outputs
Researchain Logo
Decentralizing Knowledge