Biomedical subjects
N Trehan
Publications and source records attributed to N Trehan.
Morphometric analysis of the right gastroepiploic artery and the internal mammary artery.
BACKGROUND: The internal mammary artery (IMA) and the right gastroepiploic artery (RGEA) are frequently used as conduits for coronary artery bypass grafting. METHODS: Morphometric measurements and histologic characteristics of the RGEA and the IMA were studied in 25 patients undergoing coronary artery bypass grafting. RESULTS: External radius was found to be more in the IMA (range, 18 to 56 microns; mean, 39.56 microns) in comparison with the RGEA (range, 24 to 51 microns; mean, 32.52 microns; p < 0.01). There was no significant difference between the vessels in intimal thickness (IMA: 0.0 to 0.25 micron; mean, 0.05 micron; RGEA: 0.0 to 0.28 micron; mean, 0.09 micron), internal radius (IMA: 5 to 47 microns; mean, 28.40 microns; RGEA: 16 to 42 microns; mean, 23.56 microns), area of media (IMA: 1,690 to 3,476 microns2; mean, 2,777.52 microns2; RGEA: 1,659 to 3,600; mean, 3,012.44 microns2), intimal thickening index (IMA: 0.0 to 0.02; mean, 0.01; RGEA: 0.0 to 0.13; mean, 0.01), and medial index (IMA: 0.14 to 0.60; mean, 0.36; RGEA: 0.18 to 0.63; mean, 0.39). Histologic examination of the RGEA showed more defects in continuity of internal elastic lamina and rich smooth muscle cells in the media. CONCLUSIONS: There was no difference in the morphometric measurements of the IMA and the RGEA except external radius, which was greater for the IMA. The histologic differences found in the RGEA may indicate an increased propensity for atherosclerosis of the RGEA as compared with the IMA. Some concern regarding the long-term patency of the RGEA in myocardial revascularization is warranted.
Coronary-to-coronary bypass using a free internal mammary artery: an alternative.
Paucity of conduit of adequate length or quality poses a dilemma in the occasional patient. We report such a patient, in whom we used a modified anastomotic technique using the normal right coronary artery for the proximal anastomotic site of a free right internal mammary artery graft.
Transverse approach to the femoral artery.
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Induction of high SCEs in normal cells by 11-12 kDa plasma protein overexpressed in some sleep deprived volunteers.
The present study confirmed our earlier preliminary observation of induction of high SCEs in 1 day sleep-deprived healthy volunteers and showed that the property of induction of high SCE by after-sleep-deprived (ASD) plasma was retained both in 50% ammonium sulphate precipitates and in the dialysed plasma using a membrane of 12 kDa porocity. Further, nitrocellulose bound 11-12 kDa electrophoretically isolated plasma protein from ASD individuals was found responsible for the induction of high SCE in normal whole blood cultures. A short exposure of 3 h to 5% ASD plasma was enough to induce significantly high SCEs in normal lymphocytes which had undergone 2 replication cycles after the exposure to this factor.
Coronary-to-coronary artery bypass using a free right internal mammary artery: an alternative.
Lack of a conduit of adequate length or quality poses a dilemma in the occasional patient. We report such a case in whom we applied a modified anastomotic technique using the normal right coronary artery for the proximal anastomotic site of a free right internal mammary artery graft.
Papillary fibroelastoma of the mitral valve associated with rheumatic mitral stenosis.
Papillary fibroelastoma of the mitral valve diagnosed and treated in life is extremely rare. There have been eight cases documented so far. We report the first case of a mitral valve papillary fibroelastoma associated with severe rheumatic mitral stenosis and tricuspid regurgitation with stenosis. The tumor arose from the posteromedial papillary muscle of the mitral valve. The mitral valve was replaced after excising the valve with the tumor and the tricuspid valve was repaired. The patient did well and remains asymptomatic.
A study of spontaneous echo contrast in patients with rheumatic mitral stenosis and normal sinus rhythm: an Indian perspective.
OBJECTIVE: To study the incidence of spontaneous echo contrast in left atrium of Indian patients with rheumatic mitral stenosis in normal sinus rhythm and to define its relations. SUBJECTS: Transthoracic and multiplane transoesophageal echocardiographic studies were performed in 89 consecutive patients with rheumatic mitral stenosis who were in normal sinus rhythm. RESULTS: Spontaneous echo contrast in the left atrium was seen in 57.3% of patients on multiplane transoesophageal echocardiography and in only 5.6% on transthoracic echocardiography. The mean mitral valve area was 1.07 (SD 0.33) cm2 and 1.32 (0.45) cm2 (P = 0.004), mean left atrial size was 4.27 (0.67) cm and 3.91 (0.5) cm (P = 0.029), mean diastolic pressure gradient was 12.64 (5.69) mm Hg and 10 (5.5) mm Hg (P = 0.049), and absence of mitral regurgitation was seen in 45% and 23% of patients respectively (P = 0.1). Among patients with spontaneous echo contrast, 31% had either left atrial/appendage thrombus or a history of embolism, upsilon 0% in patients without spontaneous echo contrast (P < 0.0001). CONCLUSIONS: There is a high incidence of spontaneous echo contrast in the left atrium in Indian patients with rheumatic mitral stenosis in normal sinus rhythm on multiplane transoesophageal echocardiography. These patients are likely to embolise or form thrombi in the left atrium. The presence of spontaneous echo contrast is also associated with significantly smaller mitral valve area, larger left atrium, and higher mean diastolic mitral pressure gradient.
Technique for control of difficult cardiac bleeding.
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Closed mitral valvotomy: no more a blind procedure.
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Antiinflammatory effects of an Ayurvedic preparation, Brahmi Rasayan, in rodents.
Brahmi Rasayan, an Ayurvedic preparation, was studied in rodents for its antiinflammatory effects at po doses ranging between 1 and 10 g/kg. The drug suppressed various experimentally induced inflammatory reactions and did not show any gastric irritation in antiinflammatory doses. It is suggested that it may partially mediate its antiinflammatory activity by interfering with the action and/or synthesis of prostaglandins and also perhaps by stabilization of the lysosomal membranes. Its antiinflammatory activity is comparable to that of indomethacin.
Multiplane transesophageal echocardiography for the diagnosis of acute aortic dissection.
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Successful aortic balloon valvuloplasty in critical aortic stenosis with shock.
Emergency balloon valvuloplasty was performed in a 42 year old male with critical aortic stenosis, severe congestive heart failure, and shock. Hemodynamic and clinical improvement occurred and he underwent elective aortic valve replacement. Balloon aortic valvuloplasty may provide a "bridge" to aortic valve replacement in patients with critical aortic stenosis and shock.
Retrograde coronary sinus cardioplegia.
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Spontaneous primary coronary artery dissection leading to pseudoaneurysm.
We report an interesting case of spontaneous coronary artery dissection leading to formation of a pseudoaneurysm in a asymptomatic patient detected on the coronary angiography and confirmed on surgery.
Left ventricular pseudoaneurysm.
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Nuclear imaging study of nifedipine induced modulations of central haemodynamics in severe hypertension with and without coronary artery disease.
Acute effects of Nifedipine, a calcium channel blocking agent (CCBA), on central haemodynamics in patients with severe hypertension and angiographically proved coronary artery disease (CAD) has been studied using Nuclear Ventriculography (MUGA). While peripheral vasodilatation leads to significant reduction of systemic blood pressure in all severe hypertensive patients (p < 0.0005 and p < 0.0001), the central haemodynamics did not improve significantly in patients without CAD (p = NS). However, in hypertensive subset of CAD, central haemodynamics significantly improves with rise of global ejection fraction (p < 0.001) and improvement of wall motion abnormalities (p < 0.001).
Coronary artery bypass grafting in patients with calcified aorta.
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