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Biomedical subjects

M Alam

Publications and source records attributed to M Alam.

At least 253 records · Page 14Linked to original sources
PubMed1983

Echo-phonocardiographic features of regurgitant porcine mitral and tricuspid valves presenting with musical murmurs.

Echophonographic findings of three patients with spontaneous degeneration of porcine tricuspid and mitral valves presenting with musical murmurs are reported. Echocardiography in all these patients revealed systolic or diastolic cusp flutter similar in frequency to the musical murmur on simultaneously recorded phonocardiogram. Porcine tricuspid regurgitation is usually well tolerated and can be followed clinically for many years. However, patients with mitral porcine valves usually become symptomatic or present with congestive heart failure and usually require valve surgery soon after clinical or echo-phonocardiographic findings of valve regurgitation appear.

Aged↗
PubMed1983

Echocardiographic evaluation of porcine bioprosthetic valves: experience with 309 normal and 59 dysfunctioning valves.

To determine the clinical value of echocardiographic evaluation of porcine bioprosthetic valves, the findings in all patients who had porcine bioprosthetic valve replacement and adequate quality echocardiographic studies from 1978 to 1982 were analyzed. The study includes 309 normal and 59 dysfunctioning valves. Valve dysfunction resulted from spontaneous cusp degeneration in 39 (34 valve regurgitations, 5 stenoses), infective endocarditis in 12, paravalvular regurgitation in 5, regurgitation of redundant cusps, mitral valve thrombi, and aortic stent stenosis in 3 others. Echocardiographic findings were correlated with gross surgical pathologic or autopsy findings in 45 of the 59 dysfunctioning valves. Echocardiographic abnormalities were demonstrated in 41 of 59 (69%) dysfunctioning valves. A systolic mitral or diastolic aortic valve flutter was diagnostic of a regurgitant valve caused by a torn or unsupported cusp margin and was observed in 28 of 34 (82%) regurgitant valves with no false-positive studies. Echocardiographic cusp thickness of greater than or equal to 3 mm correctly identified all regurgitant and stenotic valves with gross anatomic evidence of localized or generalized cusp thickening or calcific deposits. Echocardiographic valve abnormalities were observed in only 4 of 12 patients with infective endocarditis and in 1 of 5 with paravalvular regurgitation. Thus, echocardiography provides important information regarding the function of porcine bioprosthetic valves and is of value in the decision to replace these valves, especially when dysfunction is due to spontaneous cuspal degeneration. Echocardiography is neither sensitive nor specific in patients with infective endocarditis and paravalvular regurgitation.

Echocardiography↗
PubMed1983

Enteric fever in patients admitted to a diarrhoeal disease hospital in Bangladesh.

The hospital records of 62 patients with blood culture-proven enteric fever admitted to the Dacca Hospital of the International Centre for Diarrhoeal Disease Research, Bangladesh, over a one-year period were reviewed. Older children and young adults had the highest age-specific rates of disease. The clinical, epidemiological and laboratory features of patients with enteric fever were compared with similar information from patients in hospital for cholera and shigellosis. Patients with enteric fever had a significantly longer prodrome of illness and were more likely to have fever than patients in the other groups. Our hospital cares primarily for patients with diarrhoeal diseases and while 94% of enteric fever patients had diarrhoea, only 5% had the recognized diarrhoeal pathogens Shigella or Vibrio cholerae identified, compared to 25% of the total hospital in-patient group, suggesting that Salmonella typhi itself may be a cause of diarrhoea. Antibiotic resistance patterns of S. typhi isolates were reviewed, and one isolate was found to be multiply antibiotic resistant. The advent of an effective oral typhoid vaccine makes further work on the epidemiology of enteric fever in endemic areas such as Bangladesh a high priority.

Adolescent↗
PubMed1983

Surgical results of anomalous left coronary artery.

After undergoing a ligation of the anomalous left coronary artery from the pulmonary artery and a saphenous vein bypass graft surgery, a 53-year-old woman has had improvement in exercise tolerance and congestive heart failure for up to two years of follow-up. Comparison of the preoperative and postoperative noninvasive studies disclose that surgery improved the left ventricular volume overload and perfusion. However, there was no change in the resting or exercise ejection fraction as assessed by stress multiple-gated acquisition isotope scan.

Coronary Vessel Anomalies↗
PubMed1982

Peripheral plasma immunoreactive 6-oxo-prostaglandin F1 alpha and gynaecological tumours.

Peripheral plasma levels of immunoreactive 6-oxo-PGF1 alpha, the stable hydrolysis product of prostacyclin, were significantly higher in female patients with tumours of the genital tract than in normal controls. In the groups with malignant tumours, these high levels declined after operation and/or radiotherapy if the tumour responded to treatment. In patients who did not respond to treatment or with tumour recurrence, levels of plasma 6-oxo-PGF1 alpha remained high or even rose further. Benign gynaecological tumours were also associated with significantly raised plasma 6-oxo-PGF1 alpha levels, and these fell to normal levels immediately on surgical removal of the tumour. Possible reasons for these alterations are described. Further investigations are warranted to see whether serial measurements of plasma 6-oxo-PGF1 alpha could be used as a prognostic index for the clinical status of patients with gynaecological tumours.

6-Ketoprostaglandin F1 alpha↗
PubMed1982

M-mode echocardiographic failure to consistently identify the equally bicuspid aortic valve: correlation with orifice-view aortography.

The M-mode echocardiogram is considered a satisfactory diagnostic tool for the determination of the presence of a bicuspid aortic valve. M-mode echocardiographic failure to determine this condition is occasionally encountered and has been suggested to be due to the anatomic configuration wherein the two aortic valve leaflets are nearly equal in size. By employing a specific angiographic study (orifice-view aortography), it has been shown that accurate identification of aortic valve anatomy is possible. Ten patients having orifice-view aortographic findings of an aortic valve having two essentially equally sized leaflets have been studied both by this technique and M-mode echocardiography. Five of these had M-mode echographic evidence of a bicuspid aortic valve. However, 3 exhibited no criteria diagnostic of a bicuspid valve and 2 had only suggestive criteria. The results confirm that M-mode echocardiography alone is insufficient to determine reproducibly the presence of an aortic valvular malformation with or without stenosis when the anatomy is that of an equally bicuspid aortic valve.

Adolescent↗
PubMed1981

Dinoflagellate sterols IV: Isolation and structure of 4 alpha, 23xi, 24xi-trimethylcholestanol from the dinoflagellate Glenodinium hallii.

The dinoflagellate Glenodinium hallii was investigated for its sterol composition. Five of the six sterols were isolated and identified as cholest-5en-3beta-ol, (24xi)-24-methylcholest-5-en-3beta-ol, stigmasta-5,22-dien-3beta-ol, (22E,24R)-4 alpha, 23, 24-trimethyl-5 alpha-cholest-22-en-3 beta-ol, and 4 alpha, 23 xi, 24 xi-trimethyl-5 alpha-cholestan-3 beta-ol.

Animals↗
PubMed1981

Echocardiographic changes in the thickness of porcine valves with time.

To assess the ability of M-mode echocardiography to detect the incidence and frequency of porcine xenograft valve thickening, echocardiograms were obtained in 147 mitral and aortic porcine xenograft valves implanted in 131 patients. The patients were divided into an early group in whom the echocardiograms were performed within two months of valve replacement, and intermediate group studied two to 48 months after surgery, and a late group 48 months or longer after surgery. The porcine cusp echoes were visualized with proper gain settings, enlarged, and then recorded on a strip chart. The mean thickness of both the mitral and the aortic cusps was measured with the valve in the coapted position. The mean thickness of the porcine mitral valve increased from 1.23 +/- 0.12 in the early group to 2.3 mm +/- 0.19 in the late group (P less than .02). Aortic valve thickness increased from 0.91 mm +/- 0.07 in the early group to 2.1 mm +/- 0.37 (P less than .05) in the late group. A significant change in valve thickness was not observed in the intermediate group. In the late group of valves, 21/82 (27 percent) had a thickness greater than 3 mm. Nine of these valves (43 percent) have required replacement because of clinical dysfunction. Only 1.6 percent (1/61) of the valves in the late group with a thickness of less than 3 mm had or developed severe porcine valve insufficiency (P less than 0.001). In all ten instances, the echocardiographic assessment of valve thickness was validated on gross examination of the valve removed at surgery. This study indicates that the thickness of both mitral and aortic porcine valves can be measured by M-mode echocardiography. Valve thickness increases after 48 months and those valves with thickening of 3 mm or more are at a higher risk of developing clinical evidence of valve dysfunction.

Aortic Valve↗
PubMed1980

Mid-systolic closure of the aortic valve in hypertrophic obstructive cardiomyopathy: a pressure-related phenomenon induced by turbulent blood flow.

The purpose of this study was to determine whether mid-systolic closure and opening of the aortic valve in patients with hypertrophic obstructive cardiomyopathy (HOCM) may reflect dynamic changes of pressure induced by turbulent blood flow in the aorta and left ventricular outflow tract. Five patients with HOCM who had echocardiographic evidence of mid-systolic closure of the aortic valve and two patients with HOCM who did not have transient mid-systolic closure of the aortic valve were studied. In patients in whom mid-systolic closure was present, a transient mid-systolic drop of pressure was present in the left ventricular outflow tract, distal to the dynamic intraventricular obstruction, 17 +/- 3 mm Hg (mean +/- SEM) and in the root of the aorta, 16 +/- 4 mm Hg. In these patients the mid-systolic drop of pressure was consistently associated with a high-intensity intracardiac murmur indicative of turbulence. In the two patients in whom mid-systolic closure of the aortic valve was absent, the transient mid-systolic drop of pressure during systole was minimal (average, 3 mm Hg). The transient mid-systolic drop of pressure distal to the intraventricular obstruction can be explained on the basis of decreased pressure energy of the blood due to turbulence. Since total energy is conserved, increased kinetic energy due to turbulence occurs at the expense of a loss in pressure energy. The transient mid-systolic reduction of pressure in the turbulent zone during systole may cause a pressure differential across the open valvular leaflets resulting in a transient closure of the aortic valve.

Aorta↗
PubMed1980

Echocardiographic features of a stenotic porcine aortic valve.

M-mode and two-dimensional echocardiographic features are reported in a patient who developed stenosis of a porcine xenograph valve implanted in the aortic position. The presence of increased cusp echoes along with reduced cusp opening was the most consistent echocardiographic finding in this patient. The clinical and the echocardiographic findings were subsequently confirmed by cardiac catheterization and surgery.

Adult↗
PubMed1980

Spontaneous degeneration of porcine bioprosthetic valves.

From October, 1971, to October, 1979, 490 patients with 560 porcine bioprosthetic valves were discharged from the hospital. During these 8 years, 23 valves were removed because of failure due to spontaneous degeneration. Bioprosthetic valve survival without degeneration was at 4 years, 98.9% +/- 86 (standard error); at 5 years, 96.4% +/- 1.3; at 6 years, 90.8% +/- 2.4; and at 7 years, 84.2% +/- 3.7. There was no difference in degeneration observed with regard to sex, valve position, or whether the valves were rinsed with antibiotics prior to implantation. There was an increase in degeneration in patients 35 years old and younger compared with those more than 35 years old (p = 0.0001). Valve failure was gradual, and valve changes were noted by echocardiogram and phonocardiogram prior to actual failure. Specific factors leading to degeneration require further investigation.

Adolescent↗
PubMed1980

Tricuspid valve fluttering; echocardiographic features of ventricular septal defect.

M-mode echocardiographic features are presented in four patients with membranous ventricular septal defect. The most consistent echo findings in all the patients were the presence of fuzzy, fluttering echoes of the tricuspid valve during systole. More careful echocardiographic evaluation of the tricuspid valve in ventricular septal defect is therefore recommended.

Adolescent↗