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Biomedical subjects

S Sharma

Publications and source records attributed to S Sharma.

At least 1,621 records · Page 90Linked to original sources
PubMedDate not supplied

Failure of acetyl salicylic acid (aspirin) to reduce experimental myocardial ischaemic damage.

Rats fed on acetylsalicylic acid (aspirin) 1.5 mg/100 g body weight for a period of three weeks were subjected to myocardial infarction by s.c. administration isoprenaline hydrochloride 8.5 mg/100 g of body weight on two consecutive days. Heart specimens were taken for histological examination at 24 hr, on 5th day and 12th day. An equal number of rats were given saline to serve as control. As compared to controls aspirin-treated rats were found to have macroscopically bigger infarcts and microscopically showed persistent oedema on the 12th day. Further, no histological evidence of favourable action of aspirin was seen on the fifth day and after twenty-four hr.

Animals↗
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Our experience with Palmaz-Schatz coronary stent.

Between September 1993 and August 1994 we have implanted Palmaz-Schatz coronary stents in 44 patients. Twenty eight patients presented with stable angina and 16 with unstable angina. Stenting was carried out for denovo, focal lesions in large coronary arteries (n = 27), significant dissection during PTCA with acute threatened closure (n = 9), suboptimal results (n = 5), restenosis after PTCA (n = 2) and saphenous vein graft stenosis (n = 1). Successful delivery of the stent was achieved in 43 cases. Percent diameter stenosis was reduced from 77 +/- 11% to 10 +/- 8% and minimal luminal diameter increased from 1.08 +/- 0.28 mm to 2.92 +/- 0.39 mm. There was 1 death due to left main dissection secondary to guiding catheter trauma in a patient taken up for bail out stenting. Vascular/bleeding complications occurred in 3 patients (6.7%). There was no instance of acute or subacute stent thrombosis. Forty patients are symptom free. Eighteen patients underwent six month angiography. Restenosis (> 50% diameter reduction) was seen in 2 and a new lesion distal to stent occurred in 1 case. All have been successfully redilated. A high rate of successful delivery of the Palmaz-Schatz coronary stent can be achieved in a wide spectrum of patients with very few complications. Long term results are very gratifying and encouraging.

Angina Pectoris↗
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Coronary artery reoperations using arterial conduits: immediate and early results.

This study deals with results of coronary artery reoperations in 21 males aged 54.4 +/- 6.6 years. Native vessel coronary disease at first and second operation was nearly the same (2.7 +/- 0.6 vs 2.8 +/- 0.4 vessel, p = NS). Graft attrition and deterioration in left ventricular ejection fraction (55.9 +/- 9.2 initial vs 36 +/- 15 at reoperation, p < 0.001) necessitated reoperation in majority. Recurrence of angina (71%) and left ventricular failure (23.8%) were the clinical indicators for reoperation. Procedure was successful in 20 (95%) and had to be abandoned in 1 due to severe pericardial and sternal adhesions. Arterial grafts were utilised in 90% (18 cases, Group A and B). Total arterial revascularisation (Group A) was done in 9 (45%) using Y graft 6, combination of both mammary arteries 2, and by both mammary and inferior epigastric artery in 1. Group B patients had arterial grafts (bilateral IMA 1, Y graft 1, bilateral IMA + gastroepipolic 1, RIMA 4, and LIMA 2) in addition to a venous graft. Two patients (group C, 10%) had only venous grafts. There was no in hospital mortality or morbidity and at 10 +/- 5.2 months follow up, all are asymptomatic with negative stress test at 3 months followup in 8 cases. We conclude that coronary artery reoperations using arterial conduits can be performed safely with excellent immediate and early results.

Angina Pectoris↗
PubMedDate not supplied

Alteration in pulmonary mechanics after coronary artery bypass surgery: comparison using internal mammary artery and saphenous vein grafts.

Pulmonary function tests, arterial blood gas tensions and morbidity were compared in 50 patients undergoing coronary artery bypass graft surgery. Thirty patients had bilateral internal mammary grafts (Group 1), 5 patients had only saphenous vein grafts (Group 2) and 15 patients had a single arterial graft in addition to vein grafts (Group 3). Pleural effusion and wound infection were more common in patients with internal mammary artery grafts (p < 0.05). Patients in Group 2 required prolonged ventilation but this could be related to their underlying left ventricular dysfunction. Patients in all the three groups developed a severe restrictive ventilatory defect in the postoperative period and the degree of impairment was maximum in Group 1 patients (p < 0.01). These patients also had evidence of small airway obstruction. Thus an overall decrease in pulmonary function occurs in the postoperative period by 30 to 40% (p < 0.001). The derangement is greater in patients with arterial grafts, as a result of impaired blood supply, increase in pleural drains and additional surgical trauma secondary to mobilization of internal mammary arteries leading to delayed recovery. The awareness of these findings can be of great value in postoperative management of these patients. In addition, these observations should also be kept in mind while planning the choice of grafts in a patient undergoing coronary artery bypass graft surgery.

Case-Control Studies↗
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A follow up study of major intimal dissections treated with perfusion balloon catheter.

Major intimal dissections during coronary angioplasty are an important cause of early morbidity and mortality. In the recent past various non-surgical modalities to manage such dissections have been developed. The choice of therapy among these needs knowledge not only of immediate success but also of long term results. Data on long term follow up of patients managed with prolonged balloon inflations using a perfusion balloon catheter is limited. We herein report our experience of twenty seven consecutive patients managed by prolonged dilatations using Stack perfusion balloon catheter. All the patients had a long dissection with luminal compromise, 6 (22%) had in addition an acute complete occlusion, and in 4 (15%) there was a thrombus. Only 6 (22%) needed an emergency CABG, with the remaining having an event free hospital stay. At follow up after 6-26 months, 7/21 (33%) had severe symptoms and 5 of them underwent coronary arteriography with four having a repeat successful dilatation. The findings of this study suggest that the perfusion balloon catheter is a useful modality for management of major dissections with a restenosis rate similar to that of primary PTCA. Randomised controlled trials are required to assess its efficacy vis a vis the newer therapeutic options like stents, lasers and atherectomy.

Angioplasty, Balloon, Coronary↗
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Collateral arteries in the presence of obstructive coronary disease.

BACKGROUND: The clinical importance of coronary collaterals in the presence of obstructive coronary artery disease is not clearly defined. METHODS: We retrospectively analysed the clinical and angiographic features of 100 patients with > or = 90% luminal diameter stenosis involving at least one major coronary artery. Coronary collaterals were graded 0 to 4 (Nitzberg's classification) and studied to determine their influence on clinical parameters. RESULTS: Thirty patients had no collaterals (group I) and 70 showed collaterals (group II). There were no significant differences between groups I and II in age and sex distribution, prevalence of risk factors of coronary artery disease (hypertension, diabetes, smoking, hypercholesterolaemia), duration of symptoms of coronary artery disease and prior myocardial infarction. Groups I and II had similar types (left anterior descending 73% v. 71%; left circumflex 50% v. 50% and right coronary 37% v. 56%) and numbers of arteries involved (one 47% v. 41%; two 47% v. 40%; three 7% v. 19%). Group II had a significantly lower prevalence of rest angina (14% v. 47%, p = 0.002). This difference was also evident when the patients were re-classified according to the extent of flow through the collaterals. Those with good collateralization (Nitzberg grades 3 and 4) had a lower prevalence of rest angina (13%) compared to those with poor collateralization (Nitzberg grades 0 to 2; 35%, p = 0.02). CONCLUSION: Coronary artery collaterals may reduce the incidence of rest angina in patients with obstructive coronary artery disease.

Angina Pectoris↗
PubMedDate not supplied

Discrete subaortic stenosis: a study of 20 cases.

Twenty patients with discrete subaortic stenosis were studied during last 11 years. Cross sectional echocardiography and angiography demonstrated a membrane in 17 (85%), fibromuscullar collar in 2 (10%), and diffuse tunnel type of obstruction in 1 (5%) patient. Eighty five percent of patients had severe obstruction with average peak systolic gradients being 96.5 +/- 36.3 mm of Hg. Eight patients with membranous obstruction seen during the last 5 years underwent successful balloon dilatation with decrease in peak systolic gradient from 107.1 +/- 24.2 to 32.3 +/- 14.2. The haemodynamic benefits were sustained during 4 to 24 (mean 9.6) months followup. The results indicate that balloon dilatation can be a safe and effective treatment for thin subaortic membrane. Surgical resection is needed in patients with collar or tunnel type of obstruction.

Adolescent↗
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Left main coronary artery compression by dilated main pulmonary artery in atrial septal defect.

Left main coronary artery compression by dilated pulmonary artery in patients with atrial septal defect has previously been reported, but not well characterized. Accordingly, we review retrospectively data of patients with atrial septal defect in whom selective coronary angiograms were done. 41 patients (26 females), aged 47.3 +/- 7.4 years were studied. The pulmonary artery mean pressure was 22.7 +/- 8.3 mm Hg and all patients had left to right shunt ratio of 2:1 or more (mean ratio: 3.9 +/- 1.7). Two patients (4.8%) had left coronary ostial stenosis. There were no clinical or haemodynamic parameters to differentiate the patients with or without these changes. Two patients (4.8%) had coexistent atherosclerotic coronary artery disease. In conclusion, left main coronary trunk compression rarely occurs in patients with atrial septal defect. This information may be relevant in evaluating patients with atrial septal defect.

Adult↗
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A histomorphologic and ultrastructural study of the malignant tumours of the renal pelvis.

The study was carried at two different centres. Only 9 cases of primary malignant tumours of the renal pelvis could be collected during the period of 7 years (1984-1990). Renal pelvis malignancies constituted 0.21% of all the malignancies and 12.16% of all the malignant growths of the kidney (9 out of 74 cases). The age of these patients ranged from 24 to 70 years; the mean being 41.7 years. Male/female ratio was 8:1. Common triad of complaints (pain, haematuria and lump) was noticed in 22.2% of patients. Individually they were noticed in 77.8%, 66.7% and 44.4% of patients respectively. Transitional cell carcinoma was the commonest, seen in 7 patients (77.8%) whereas squamous cell carcinoma and adenocarcinoma were noticed in one patient (11.1%) each. Hydronephrosis, chronic pyelonephritis and nephrolithiasis were noticed in 66.7%, 44.4% and 22.2% of patients respectively. Ultrastructural study of urothelial tumours revealed tumour cells in various stages of differentiation with loss of intercellular junctions and dense collection of rough endopasmic reticulum fibrils around the nucleus.

Adenocarcinoma↗
PubMedDate not supplied

Retrograde non-transseptal balloon mitral valvuloplasty--an initial experience.

Eleven patients with symptomatic isolated non-calcific mitral stenosis were treated with retrograde nontransseptal balloon mitral valvuloplasty. This new technique utilizes a specifically designed steerable catheter to enter the left atrium retrogradely via the left ventricle thus avoiding transseptal puncture, an essential step in other methods of balloon mitral valvuloplasty. Technical success was obtained in ten (91%) patients. Mitral valve area increased from 0.8 +/- 0.2 to 1.8 +/- 0.4 cm2 and the transmitral gradient decreased from 23.9 +/- 7.7 to 8.2 +/- 2.8 mmHg. There were no major complications such as cardiac perforation, embolic events, cardiac tamponade or severe mitral regurgitation. This early experience, the first outside Greece (centre of origin) indicates that retrograde nontransseptal balloon mitral valvuloplasty is a simple, effective and safe technique with results comparable with other techniques of mitral balloon dilatation which require transseptal catheterisation. Further experience involving multicenteric trials, is required to determine the overall efficacy of this technique for percutaneous balloon mitral valvuloplasty.

Adolescent↗
PubMedDate not supplied

Enalapril for prevention of restenosis after coronary angioplasty.

We have evaluated the effect of enalapril in the prevention of restenosis after percutaneous transluminal coronary angioplasty by a randomized trial conducted on 95 patients. The treatment group (n = 46) received enalapril 10 mg/day besides aspirin with calcium blockers, beginning 24 hours before coronary angioplasty. The conventional medical treatment group (n = 49) received only aspirin and calcium blockers. Enrollment required the presence of angina pectoris and successful dilatation of all significant coronary narrowings. All patients were followed up for at least 6 months. Restenosis was identified by symptoms and exercise testing and confirmed by angiography. The incidence of angiographic restenosis was 34% in the enalapril group and 31% in the conventional treatment group. Long term angiotensin converting enzyme inhibition with enalapril in a dose of 10 mg per day does not prevent restenosis after coronary angioplasty.

Adult↗
PubMedDate not supplied

Amlodipine monotherapy in mild to moderate hypertension.

The efficacy and safety of amlodipine was evaluated in 20 patients of mild to moderate hypertension in a single blind, placebo controlled, noncomparative study. Patients with a baseline diastolic blood pressure of > 90 and < 115 mmHg while on placebo were admitted to a 4 week active treatment phase. Amlodipine produced a significant (p < 0.05) reduction in mean systolic (177 mmHg to 145 mmHg) and diastolic blood pressure (106 mmHg to 84 mmHg) after 4 weeks treatment in all patients. 95% of the patients had their diastolic blood pressure reduced to < or = 90 mmHg by the end of the study period. There was no significant change in heart rate or in the laboratory parameters with amlodipine therapy. Seven patients reported mild to moderate adverse events which did not require discontinuation of therapy. This combination of efficacy and tolerability, together with convenience of once daily dosing, should ensure the usefulness of amlodipine in the treatment of hypertension.

Adult↗
PubMedDate not supplied

Transcatheter embolization of a coronary artery fistula.

A coronary artery fistula from left anterior descending coronary artery to right ventricle was successfully occluded by transcatheter embolization using steel coils. Transcatheter embolization seems to be the treatment of choice for coronary artery fistulas.

Cardiac Catheterization↗
PubMedDate not supplied

Percutaneous mitral valvotomy in 200 patients using Inoue balloon-immediate and early haemodynamic results.

We report our experience with percutaneous balloon valvotomy using the Inoue technique in 200 cases with rheumatic mitral stenosis. The procedure was successful in 195 (97.5%) cases with a fluoroscopy time of 9 +/- 2.7 and procedure time of 60 +/- 19 minutes. Mitral valve area as estimated by Gorlin's equation and pressure half time increased from 0.86 +/- 0.17 to 2.21 +/- 0.41 and from 0.94 +/- 0.14 to 1.90 +/- 0.26 (p < 0.001) respectively. Other hemodynamic variables including mitral valve gradient, cardiac output, left atrial mean and pulmonary artery pressure improved significantly. There were no deaths and the incidence of major complications was small. Increase in mitral regurgitation was observed in 35 (17.9%) with grade 2+ increase in 7 (3.6%). Inoue balloon technique is safe, easy to perform and provides excellent clinical and hemodynamic benefits in majority of cases.

Adult↗
PubMedDate not supplied

Malignant ameloblastoma. A case report.

The cytologic features of malignant ameloblastoma, a rare tumor of the jaw, are described. Fine needle aspiration smears showed high cellularity, with small basaloid and polygonal epithelial cells with mild to moderate pleomorphism lying singly or in clusters. In Giemsa-stained smears, pinkish stroma with stellate cells or irregularly shaped nuclei and isolated spindle cells were seen in the background. Histopathology of the tumor showed sheets of cells with features of malignancylike atypical mitosis and vascular invasion. The tumor cells stained positive for keratin on immunohistochemistry. A review of cytology smears revealed that the features were sufficiently characteristic of an ameloblastoma, but it was difficult to label the lesion malignant on fine needle aspiration cytology.

Adult↗