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P K Goel

Publications and source records attributed to P K Goel.

At least 19 recordsLinked to original sources
PubMed2006

Evaluation of AnnAGNPS in cold and temperate regions.

Identification of the pollution sources and understanding the processes related to runoff generation and pollution transportation is effective for the water quality management and selection of the Best Management Practices. The ANNualized AGricultural Non-Point Source (AnnAGNPS) model was applied to a watershed in Southern Ontario to evaluate the hydrology and sediment component from the non-point sources. The model was run for two years (1998 to 1999); one year's data was used to calibrate and the second year's data was used for validation purposes. The model has under predicted runoff amount and over predicted the sediment yield. However, the simulated runoff and sediment yield compared fairly well with the observed data indicating that the model had an acceptable performance in simulation of runoff and sediment. The study is still in progress to assess its performance for estimation of TMDL and improvements needed for the model to use under Ontario conditions.

Calibration↗
PubMed2001

Inoue balloon mitral valvotomy in patients with atrial septal aneurysm.

Atrial septal aneurysms (ASA) are not uncommonly detected in patients with rheumatic mitral stenosis and pose problems during transeptal puncture in patients undergoing balloon mitral valvotomy. From a period of August 1995 to May 1998, we performed a total of 680 Inoue Balloon Mitral Valvotomy (IBMV) procedures with ASA noted in 30 patients, 13 of diffuse and 17 localized type. Transesophageal echocardiography (TOE) was used in all patients with suspected aneurysm on transthoracic echo (TTE) for exact three-dimensional delineation of the location and extent of the aneurysm. The localized type of aneurysms were further subcategorized into five types viz. antero-superior and leftwards (6), postero-superior and rightwards (2), antero-inferior and leftwards (2), postero-inferior and rightwards (5), and central (2), depending on their location in the atrial septum. The site for transeptal puncture was decided after this localization and the remainder of the IBMV procedure was as usual. In the set of thirteen patients with diffuse type of atrial septal aneurysms all but one case had a successful transeptal puncture using standard technique except for a somewhat inferior puncture site so as to be perpendicular to the plane of atrial septum and a successful mitral valve dilatation was possible at first attempt. In the set of 17 patients with localized type of aneurysms, all had a successful transeptal puncture except one. In patients with aneurysms localized antero-superiorly and leftwards the septal puncture was done in a slightly inferior location with transeptal needle pointing some what more posterior, i.e. 5 or 6 o'clock position and in patients with aneurysms localized postero-inferiorly the puncture was done more cephalic with needle directed somewhat anterior, i.e. 3-2 o'clock position. In the two patients with Atrial septal aneurysms located postero-superiorly and to the right the puncture was done slightly inferior but with transeptal needle pointing to about 3 or 2 o'clock position and in the single patient with antero-inferior location the puncture was done in slightly higher but with a more posterior directed needle, i.e. 5-6 o'clock position. The two patients with centrally located localized type of aneurysms had successful transeptal puncture with standard needle direction (4 o'clock) but at a slightly inferior location. We conclude that a good localization of atrial septal aneurysms using transesophageal echocardiography and our technique of transeptal puncture leads to a successful outcome in majority of cases undergoing Inoue balloon mitral valvotomy with associated atrial septal aneurysms.

Adult↗
PubMed2001

Slow coronary flow: a distinct angiographic subgroup in syndrome X.

Patients evaluated for chest pain with angiographically normal coronary arteries are usually labelled syndrome X. A portion of these patients may not have a cardiac cause for their symptoms. The authors aimed to study a subset within this group who showed the phenomenon of slow coronary flow (SCF) as evidenced by a slow antegrade progression of the dye on the coronary arteriogram to see if this could be used as a marker of myocardial ischemia. This observational study included 207 patients being evaluated for suspected coronary artery disease and found to have normal coronary angiograms. SCF was seen in 49 of these patients (23.7%) while the remaining 158 (76.3%) had normal coronary flow (NCF), as detected by the corrected thrombosis in myocardial infarction (TIMI) frame count method (TIMI frame count more than 2 SD of normal). Forty of the 49 patients (82%) in the SCF group had classical angina as compared with only 51 of the 158 patients (32%) in the NCF group (p<0.01). Also, a definitively positive exercise test was observed more commonly in the SCF group than in the NCF group (71% vs 42%, p < 0.01). The authors conclude that SCF patients constitute a definite subset within the wide spectrum of syndrome X and that the phenomenon of SCF could be used as a marker for myocardial ischemia.

Adult↗
PubMed2000

Effect of Inoue balloon mitral valvotomy on severe pulmonary arterial hypertension in 315 patients with rheumatic mitral stenosis: immediate and long-term results.

BACKGROUND AND AIMS OF THE STUDY: Despite advances in surgical techniques, mitral valve surgery in patients with severe pulmonary arterial hypertension (PAH) causes considerable mortality and morbidity. Balloon mitral valvotomy (BMV) is an established alternative to treat high-risk surgical patients with mitral stenosis (MS). The study aims were to evaluate immediate and long-term efficacy of BMV in patients with MS and severe PAH, compared to those with mild/moderate PAH. METHODS: Among 1,125 patients who underwent Inoue BMV, 315 had severe PAH (mean pulmonary artery (PA) pressure > or = 50 mmHg (group I; 79 of these patients had suprasystemic PAH). Results from this group were compared with those of patients with mild/moderate PAH (group II). RESULTS: Group I patients were younger and more symptomatic (mean PA pressure 62 +/- 10.6 mmHg versus 32.6 +/- 8.2 mmHg in group II). Before BMV, mean transmitral gradient (17.8 +/- 6.5 versus 14.4 +/- 5.4 mmHg) and pulmonary capillary wedge pressure (PCWP) (31.6 +/- 6.1 versus 22.8 +/- 6.2 mmHg) were significantly higher, while mitral valve area (MVA) (0.66 +/- 0.2 versus 0.85 +/- 0.2 cm2) was significantly lower in group I. After BMV, PA mean pressure was significantly reduced (34.8 +/- 11.2 and 21.1 +/- 8.4 mmHg), transmitral gradient (8.0 +/- 3.9 and 6.9 +/- 3.2 mmHg) and mean PCWP (12.8 +/- 5.8 and 11.0 +/- 5.1 mmHg) in groups I and II, respectively, with a comparable increase in MVA (1.77 +/- 0.4 and 1.84 +/- 0.5 cm2). Group I patients had worse baseline hemodynamic parameters than group II, but the former had a higher absolute gain in hemodynamic parameters. Residual severe PAH after BMV was seen in 9.8% of patients, with PA pressures normalized in 9.5%. Among 79 patients with suprasystemic PA pressure (mean PA systolic pressure 116.6 +/- 28.2 mmHg), 16.5% normalized their PA pressures and 25.3% had residual severe PAH. At mean follow up of 33 months, 80.4% were in NYHA class I. Mean PA systolic pressure in 161 patients was 39.0 +/- 14.2 mmHg compared with a post-BMV value of 55.0 +/- 16.9 mmHg; thus, a sustained fall in pressure was demonstrated at follow up. CONCLUSION: Inoue BMV is safe and effective in patients with MS and severe PAH. Although these patients have worse clinical and hemodynamic parameters before BMV, they achieve a greater absolute gain in terms of improvement in all hemodynamic parameters.

Adult↗
PubMed1998

Influence of sub valvular pathology on immediate results and follow up events of Inoue balloon mitral valvotomy.

We evaluated the influence of sub valvular pathology (SVP) on the immediate results and follow up events of Inoue Balloon Mitral Valvotomy (IBMY) in 206 patients with severe SVP (Group I) and compared their outcome with 206 age and sex matched patients selected from the rest of 619 patients having mild/moderate SVP (Group II). Pre-procedure echocardiographic recordings were reviewed and mitral valve morphology was evaluated using U.S. California Score. The severe SVP group had lower mitral valve areas (MVA) (0.7 cm2 vs. 0.8 cm2) and higher mean pulmonary artery pressure (MPAP) (46.3+/-16.9 mmHg vs. 40.7+/-16.25 mmHg) and mean pulmonary capillary wedge pressure (PCWP) (27.5+/-7.3 mmHg vs. 25.7+/-8.0 mmHg) (p<0.001). IBMV was done using standard technique. The procedure was technically successful in 192/206 patients (93.2%) in group I and 187/206 (91%) in group II (p=ns). The mean transmitral gradient decreased from 24.8+/-7.6 mmHg to 7.46+/-3.4 mmHg while mean PCWP fell from 27.5+/-7.3 mmHg to 12.2+/-5.6 mmHg and MPAP fell from 46.3+/-16.9 mmHg to 23.6+/-12.2 mmHg (p=<0.001). MVA increased from 0.7+/-0.2 cm2 to 1.7+/-0.4 cm2 (p=<0.001). Severe mitral regurgitation (MR) occurred in 2 patients out of which one patient, who had associated coronary artery disease, died post operatively, and moderate MR occurred in 8 patients. The results achieved in patients with severe SVP were not statistically different from those with mild/moderate SVP. The benefits achieved immediate post IBMV were sustained in 184 patients with severe SVP who were available for follow up at a mean duration of 15.2 months (range 3 months to 51 months). Thus IBMV is safe and effective in patients with severe SVP. This group of patients with severe SVP are more hemodynamically deranged pre-BMV and also achieve better hemodynamic benefit compared to those with mild/moderate SVP. Severe SVP does not have any adverse effect either on immediate results (success/occurrence of MR) or on intermediate term follow up.

Adult↗
PubMed1998

Pressure zone used and the occurrence of mitral regurgitation in Inoue balloon mitral commissurotomy.

Mitral regurgitation (MR) is a known complication of Inoue balloon mitral commissurotomy (BMC) and has been variously ascribed to the presence of severe subvalvular pathology (SVP), preexisting MR, calcification, or oversizing. The pressure zone used--with the low pressure zone (LPZ) the lower half of the spectrum of sizes available out of a single balloon, and the high pressure zone (HPZ) the upper two levels, i.e., within 2 mm of its maximum size--could have a bearing on the occurrence of MR, but has not been studied before. We analysed 251 consecutive patients (mean age 28.6 + 9.7 years), undergoing BMC from October 1993 onwards, with pliable, non-calcific, splittable (bilateral dark zones present) valves with not more than trivial MR (1 + in grades of 1-4). Balloon sizing was done with standard formula using height with stepwise dilatation starting 2 mm below the reference size. Thirty-two patients additionally had severe SVP. Patients were divided into two groups, HPZ-BMC and LPZ-BMC, depending upon the final balloon size needed for a successful result. Incidence of MR (2+ or more) was significantly lower in the LPZ BMC (18%) vs. HPZ BMC (32.2%) (P < 0.05). Moderate to severe MR (3+/4+) was also less in LPZ BMC (2.8%) vs. HPZ BMC (8.2%) (P < 0.05). Amongst patients with severe SVP, 3/15 (20%) developed MR in the LPZ-BMC group (all mild only) as against 8/17 (42%) (P < 0.05) in the HPZ-BMC group with half of them having moderate to severe MR. In 54 patients where the reference size had to be exceeded, no patient (0/8) developed MR as long as the higher size was in the LPZ of the particular balloon used as compared to 17/46 (36.9%) who developed MR when the size used fell in the HPZ. We conclude that the pressure zone used has a strong bearing on the occurrence of MR in Inoue BMC and that a low-pressure strategy could avoid MR.

Adult↗
PubMed1998

Re Grodman et al.

Explore the source record for details and available documents.

Coronary Angiography↗
PubMed1998

Trends in the use of radiology with inpatients: what has changed in a decade?

OBJECTIVE: Our goal was to evaluate trends in the use of radiology with inpatients in the 10-year period of 1984-1993. MATERIALS AND METHODS: We retrospectively reviewed administrative data from a 751-bed, tertiary care hospital between October 1, 1983, and September 30, 1993 (Fiscal years 1984-1993). We coded each study by imaging technique: CT, MR imaging, sonography, nuclear medicine, or conventional studies (plain films and fluoroscopy). Echocardiography, cardiac catheterization, and angioplasty procedures were omitted. The number of admissions per year was adjusted for severity of disease (case-mix-adjusted admission [CMA]). We used relative value units to evaluate workload changes during the study period. We assessed significance of trends using linear regression analysis. RESULTS: The total number of imaging studies per CMA decreased during the study period (p = .0001). This was due to a decrease in the number of conventional studies (p = .0001) and sonograms per CMA (p = .02), despite significant increases in the numbers of CT (p = .005) and MR imaging (p = .0001) studies per CMA. No significant change existed in the number of nuclear medicine studies per CMA (p = .11). The global, professional, and technical relative value units per CMA rose during the latter half of the study. CONCLUSION: The overall number of imaging studies per CMA decreased during the decade, despite a significant rise in the use of CT and MR imaging, suggesting that these new imaging techniques are replacing older ones. To control further increases in overall imaging costs, priority should be placed on understanding the patterns of use for CT and MR imaging techniques and curbing their inappropriate use.

Adult↗
PubMed1997

Platelet aggregability and occurrence of restenosis following coronary angioplasty.

Restenosis following percutaneous coronary angioplasty (PTCA) is a complex medical problem occurring in nearly a third of the patients undergoing PTCA with no single definite predictor demonstrated in an individual patient. Platelets are known to play an important role in the pathogenesis of the restenotic process. However, no known parameter of platelet function or activity has been studied as a risk factor predicting the occurrence of restenosis. We prospectively assessed platelet activation in twenty two consecutive patients with stable angina who underwent a successful PTCA for single vessel coronary artery disease. Platelet activation levels were measured using aggregability curves derived from unclotted blood samples on a platelet aggregometer using varying concentrations of adenosine di-phosphate (ADP) in the following time sequence: (1) Basal i.e. pre-PTCA, (2) post-PTCA day 1, (3) post-PTCA day 7, and (4) post-PTCA day 28. Occurrence of restenosis was studied using angiographic follow-up in all patients. At follow-up, seven of the twenty two patients studied developed restenosis. There was no significant difference or any specific trend noted over time in the levels of platelet aggregability in the study group as a whole (basal: 30.0 +/- 15.4%, post-PTCA day 1: 32.5 +/- 16.1%, post-PTCA day 7: 34.6 +/- 15.4% and post-PTCA day 28: 32.6 +/- 16.1%). However, when the patients were subgrouped into those with and without restenosis, the patients with restenosis had a significantly higher basal platelet aggregability (38.7 +/- 16.3%) versus those who did not develop restenosis (25.0 +/- 12.1%), p = 0.0128. We conclude that patients developing restenosis after PTCA have a significantly higher basal platelet aggregability and this could be used as a marker for its occurrence in an individual patient.

Adenosine Diphosphate↗
PubMed1997

Dilatation of congenital valvular aortic stenosis using Inoue balloon.

Balloon dilatation of valvular aortic stenosis is often associated with problems of balloon seating across the valve and slippage during performance of dilatation. We describe 2 patients with congenital aortic stenosis who underwent balloon dilatation using the Inoue balloon, which to the best of our knowledge has not been reported earlier. The technique and its advantages and limitations in aortic valve dilatation are discussed.

Adolescent↗
PubMed1997

Absent conal septum in tetralogy of Fallot. An angiographic study.

Absent conal septum in tetralogy of Fallot (TF) is usually noted intraoperatively when the ventricular septal defect (VSD) is found abutting the pulmonary valve, its superior rim being nearly inaccessible transatrially, and the posterior rim being separated from the tricuspid valve (TV) by a muscular ridge. The authors retrospectively analyzed angiograms of 208 consecutive patients with TF seen at their center from July 1989 to December 1995 for absence of the conal septum and the presence of an interval between the TV and the margin of the VSD in 30 degrees right anterior oblique view. In 13 (6%) patients, angiograms were inadequate or of poor quality for assessment and were excluded. Twenty-two of the remaining 195 (11%) patients had a large muscular interval between the tricuspid annulus and the margin of the VSD, which was associated with an absent conal septum in 14 (7.2%) and a diminutive septum in 8 (4%) patients. Nine of the 14 patients with an absent conal septum at angiography underwent surgery, and this finding was confirmed in all. The authors conclude that absent conal septum is not uncommon in TF and constitutes an important variation in its anatomy that can be identified preoperatively at angiography for optimal surgical management.

Coronary Angiography↗
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

Skeletal age as a determinant of bone mass in preadolescent females.

OBJECTIVE: To evaluate the association between chronological age, skeletal age, pubertal stage, and basic anthropometry with bone mass of the total body, forearm, and second metacarpal bone in 456 healthy Caucasian females, aged 8-13 years. DESIGN: Total body and forearm bone measurements were performed by dual X-ray absorptiometry, while bone mass of the second metacarpal was assessed by radiogrammetry. Skeletal age (SA) was assessed by the FELS method and pubertal stage was self-determined by selecting corresponding illustrations of breast and public hair development. The Cp criterion was used to select the best multiple regression model containing the subset of independent variables with the least bias and best predictive ability for each of the measured bone mass variables. RESULTS: Of all the independent variables, weight, stature, and SA emerged as the most significant predictors for almost all the bone mass variables. Multiple regression models were created based on the Cp criterion with the resulting R2 (adjusted) for bone mineral content of total body, proximal forearm, ultradistal forearm, length of second metacarpal, as well as of total, medullary, and cortical areas: 0.793, 0.523, 0.390, 0.602, 0.232, 0.073, and 0.264, respectively. The measured bone variables were also regressed on SA using either quadratic or linear equations, depending on the shape of the cubic splines used for the best curve fitting. Significant positive association (p < 0.0001) of SA and each of the bone variables was noted, the highest being with bone mineral density and content of total body (R2 = 0.176, 0.338) and proximal and ultradistal forearm (R2 = 0.216, 0.203, 0.106, 0.201), respectively, as well as with the length of the second metacarpal bone (R2 = 0.339). Chronological age and pubertal stage did not have statistically significant predictive abilities for bone mass variables in the multiple regression models. CONCLUSIONS: We conclude that skeletal age is a powerful determinant of bone mass in children. It can be used as the criterion for the selection of a biologically homogeneous population with regard to bone mass. This may be important for the design of intervention studies targeting bone mass of children and adolescents.

Absorptiometry, Photon↗
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↗