Biomedical subjects

Oben Baysan

Publications and source records attributed to Oben Baysan.

24 records · Page 2Linked to original sources

PubMed2005

Chronic heavy ethanol consumption is associated with decreased platelet aggregation in rats.

Although moderate alcohol consumption seems to be protective against atherosclerosis, coronary artery disease rate increases with its higher doses. Platelet aggregation is an important process which contributes to the atherosclerosis. The aim of this study was to determine whether heavy ethanol consumption stimulates or inhibits platelet aggregation. Fourteen adult male Wistar rats were used. Ethanol (7.2%, v/v) in a modified liquid diet was given to eight rats for 21 days, which mimicked characteristics similar to human chronic alcoholism. Six rats constituted the control group. Adenosine diphophate (ADP) and collagen-induced platelet aggregation was measured in whole blood. We found reduced ADP-induced mean maximal aggregation in the alcoholic rat group compared to the control group at dose of 5 microM (p < 0.005). We also found decreased platelet aggregation responses to collagen in the alcoholic group (p < 0.006 for 2 microg/ml collagen, and p < 0.05 for 5 microg/ml collagen). In conclusion, chronic heavy ethanol consumption results in the decreased platelet aggregation in a rat model of alcoholism. Therefore, increased mortality from coronary artery disease in chronic alcoholism may be explained by other factors such as dietary imbalances and coexisting conditions, which include hypertension and depression.

Adenosine Diphosphate↗

PubMed2005

Utility of myocardial performance index measured by left ventricular catheterization.

BACKGROUND: Myocardial performance index (MPI) is a valuable index of global ventricular performance. It is almost always measured by Doppler echocardiography. The purposes of this study were (I) to compare MPI measured by catheterization (MPIc) and that measured by Doppler echocardiography (MPId), and (2) to compare it with the functional status. MATERIALS AND METHODS: The study included 80 patients who had undergone left heart catheterization. The MPIc was measured from the pressure recordings obtained at left ventricle and aorta. RESULTS: Mean MPId and MPIc were 0.40 +/- 0.12 and 0.42 +/- 0.12, respectively. Mean left ventricular end diastolic pressure (LVEDP) was 13 +/- 5 mm Hg. Mean heart rate was 77 +/- 11 beats/min. Mann-Whitney U test revealed that MPIc could discriminate between the functional statuses of the patients. The regression analysis revealed that there is a good correlation between MPIc and MPId, LVEDP or heart rate. There was no significant difference between MPIc and MPId (p > 0.05). CONCLUSION: The present data show that (I) the MPIc has a strong correlation with MPId; (2) it is a good discriminator of functional status. It may provide an additional information regarding the left ventricular performance in patients who underwent the cardiac catheterization.

Analysis of Variance↗

PubMed2004

A different method for measuring mitral valve area with special emphasis on concomitant aortic regurgitation: A new application of proximal isovelocity surface area method.

Measurement of mitral valve area is still a challenge for the echocardiographers. Each method has its own limitations. In this study we assessed a different method and compared it with the other methods. The study included 50 consecutive patients with mitral stenosis. The reference method was planimetry. The suggested method was compared with the pressure half-time method, proximal isovelocity surface area method with and without angular correction, and the continuity method. There was a good correlation between each method and planimetry. The suggested method had the best correlation both for patients with and without aortic regurgitation. The pressure half-time method and continuity method overestimated the mitral valve area for patients with aortic regurgitation, whereas proximal isovelocity surface area method without angular correction overestimated the area in all patients. In conclusion, this method has very good correlation with planimetry. It can be used both in patients with and without aortic regurgitation.

Adult↗

PubMed2004

A novel method to estimate pulmonary artery wedge pressure using the downslope of the Doppler mitral regurgitant velocity profile.

Continuous-wave (CW) Doppler recording of mitral regurgitation (MR) is a reflection of the left ventriculoatrial pressure gradient. Accordingly, this jet may yield information about pulmonary artery wedge pressure (PAWP). In this study, we derived and then evaluated a novel method for prediction of PAWP. Patients (n=80) with moderate to severe MR and left ventricular dysfunction were included in the study. Transthoracic echocardiography was performed in patients during pulmonary artery pressure monitoring. A satisfactory CW Doppler recording of MR was obtained in 63/80 (78%). On the late descending portion of the CW recording, the time from a velocity of 4 m/sec to the end of the jet was defined as t1, and from 3 m/sec to the end of the jet as t2. Mathematical derivation of t1/t2 as a predictor of PAWP, was performed based on Weiss' derivation. If t1/t2 was <1.30, the PAWP was normal. If t1/t2 > 1.44, the PAWP was > 16 mmHg. With this new mathematical derivation, it appears that the downslope of the CW Doppler MR waveform may be able to distinguish a normal from elevated PAWP.

Algorithms↗

PubMed2004

Stenting the undeployed stent.

Undeployment of a stent which poses a potential risk for future events may become a serious problem in the catheter laboratory. Herewith, we present a case in which we successfully stented an undeployed stent in the distal right coronary artery.

Angioplasty, Balloon, Coronary↗

PubMed2004

Impedance cardiographic monitoring during pericardiocentesis: comparison with echocardiography.

OBJECTIVE: Thoracic impedance cardiography (TIC) is a noninvasive method which has proved to be useful in monitoring the haemodynamic status of the patients. In this study, we evaluated the TIC findings in patients with pericardial effusion and cardiac tamponade. METHODS AND RESULTS: The study consisted of patients with pericardial effusion with (group A) or without (group B) cardiac tamponade (CT). The stroke volume, cardiac output and ejection fraction was measured by both echocardiography and TIC. The measurements were done at baseline in both groups and following pericardiocentesis in group A. The variables were compared by linear regression analysis, paired sample's t test and chi-square test. The study included 32 patients. Group A consisted of 16 patients and group B of 14 patients. Two patients were excluded from comparisons because of insufficient quality of the echocardiographic examination. There were no significant differences between group A and B with regard to demographic features. Both echocardiographic and TIC measurements at baseline revealed decreased cardiac output, EDV and SV in group A and EF was not different. Linear regression analysis revealed that echocardiography and TIC were in significant correlation with regard to cardiac output, enddiastolic volume, stroke volume (p < 0.01) but not ejection fraction (p = 0.8910). The correlation was also present after pericardiocentesis. CONCLUSIONS: TIC can be safely used in patients with pericardial effusion. It provides suggestive data for the diagnosis of CT and can be used as a means of monitoring the results of the pericardiocentesis.

Adult↗