Biomedical subjects

Irem Dincer

Publications and source records attributed to Irem Dincer.

10 recordsLinked to original sources

PubMed2006

Effects of thyroxine therapy on right ventricular systolic and diastolic function in patients with subclinical hypothyroidism: a study by pulsed wave tissue Doppler imaging.

INTRODUCTION: The effects of l-thyroxine (l-T(4)) replacement for subclinical hypothyroidism (SH) on right ventricle (RV) functions has not been previously studied by means of pulsed wave tissue Doppler imaging (PWTDI). We investigated the effects of l-T(4) therapy on RV function in patients with SH using PWTDI. PATIENTS AND METHODS: Fifty-three patients with newly diagnosed SH and 25 controls were evaluated by standard echocardiography and PWTDI. After euthyroidism was restored by l-T(4), measurements were repeated. Myocardial systolic wave (S(m)) velocity, isovolumic acceleration (IVA), myocardial precontraction time (PCT(m)), and PCT(m) to contraction time (CT(m)) ratio were calculated as systolic indices. Early (E(m)) velocity, late (A(m)) velocity, E(m) to A(m) ratio, and myocardial relaxation time (RT(m)) were determined as diastolic measurements. RESULTS: S(m) was similar in patients and controls, whereas IVA was significantly lower in patients with SH (P < 0.001). SH patients had significantly decreased E(m) velocity, whereas A(m) velocity and E(m) to A(m) ratio did not differ. PCT(m) and RT(m) were significantly longer, and PCT(m) to CT(m) ratio was significantly higher in patients (P = 0.002, P = 0.002, P < 0.001, respectively). S(m) velocities were similar before and after l-T(4) replacement, whereas IVA significantly increased after therapy (P < 0.001). E(m) tended to increase (P = 0.05), whereas A(m) and E(m) to A(m) ratio were not changed. PCT(m), PCT(m) to CT(m) ratio, and RT(m) decreased significantly (P < 0.001 for all). CONCLUSIONS: SH is associated with RV systolic and diastolic dysfunction, and l-T(4) treatment improves these abnormalities. PWTDI, especially IVA, may be a suitable tool for the early detection of RV systolic dysfunction.

Adult↗

PubMed2006

Effect of statin treatment on coronary collateral development in patients with diabetes mellitus.

Coronary collateral development is an important compensatory mechanism in advanced coronary artery disease, and patients with diabetes mellitus have impaired coronary collateral development. This study tested the hypothesis that statin treatment may increase coronary collateral development in patients with diabetes mellitus. The study population consisted of 149 consecutive diabetic patients who underwent clinically indicated coronary angiography and had >95% stenosis of > or =1 major coronary artery. Clinical information, including age, gender, history of hypertension, smoking, myocardial infarction, clinical presentation, and medications, was recorded before coronary angiography. Coronary collaterals were graded according to the Cohen-Rentrop method. Collateral grading was classified as poor when the collateral grade was 0 to 1 and good when it was 2 to 3. Among 149 patients (85 men; mean age 62 +/- 10 years), 74 (56%) were receiving statin treatment. In multivariate analysis, among demographic, clinical, and angiographic parameters, only statin therapy (odds ratio 3, 95% confidence interval 1.5 to 6.03, p = 0.002) and stable angina pectoris (odds ratio 3.24, 95% confidence interval 1.42 to 7.41, p = 0.005) were found to be independent predictors of better collateral formation. In conclusion, stable angina pectoris and statin treatment are associated with better coronary collateral development in patients with diabetes mellitus.

Angina Pectoris↗

PubMed2006

The long-term behavior and predictors of left ventricular hypertrophy in hemodialysis patients.

BACKGROUND: The long-term behavior of left ventricular hypertrophy (LVH) was evaluated and potential predictors of change in left ventricular mass index (LVMI) in hemodialysis (HD) patients were determined. METHODS: One hundred eight patients on regular HD treatment were included. In addition to hematologic and biochemical evaluations, annual echocardiography and 24-hour ambulatory blood pressure monitoring were performed in all patients. During the median follow-up of 50 months (range, 12 to 63 months), a median of 4 echocardiographic examinations were performed in each patient. The presence of LVH was defined on the basis of an LVMI greater than 131 g/m2 for men and greater than 100 g/m2 for women. RESULTS: Eighty-two patients (75.9%) had LVH at baseline. LVH status was stable in 64 patients, whereas it changed on at least 1 occasion in the remaining patients (40.7%). LVH disappeared during the first year in 8 patients and beyond the first year of dialysis therapy in an additional 9 patients. An 8.0 +/- 39.6-g/m2 decrease in LVMI was detected between the first and final evaluations. Independent predictors of change in LVMI were C-reactive protein level (P < 0.001), baseline hemoglobin level (P = 0.025), and baseline postdialysis systolic blood pressure (P = 0.003). Twenty-four-hour systolic blood pressure was the only independent predictor of both LVMI (P < 0.001) and LVH (P = 0.001) at baseline. Nighttime systolic blood pressure and C-reactive protein level were found to be independent predictors of final LVMI (P < 0.001 for both). Independent predictors of LVH at the end of the study were 24-hour systolic blood pressure (P = 0.022) and C-reactive protein level (P = 0.003), whereas hemoglobin level had marginal significance (P = 0.051). CONCLUSION: Progressive LVH is not inevitable in HD patients. Aggressive treatment against the predictors may result in regression of LVMI and may improve patient outcome.

Adult↗

PubMed2006

Association between the dosage and duration of statin treatment with coronary collateral development.

BACKGROUND: The coronary collateral circulation is an alternative source of blood supply to myocardium in the presence of advanced coronary artery disease and the therapeutic promotion of collateral growth appears to be a valuable treatment strategy in these patients. Although it has been shown in in-vivo studies that 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins) promote vasculogenesis and accelerate coronary collateral development in ischemic tissues, there are discordant results in clinical studies. Our aim was to investigate the effect of statin therapy, including dosage and duration of treatment, on coronary collateral growth in patients with advanced coronary artery disease. METHODS: Study population consisted of 400 (306 men, with the mean age of 62+/-10 years) consecutive patients who have undergone clinically indicated coronary angiography and had at least one major coronary artery stenosis of > or =95%. Coronary collaterals were graded from 0 to 3 according to the Cohen-Rentrop method and patients with grade 0-1 collateral development were regarded as having poor collateral and patients with grade 2-3 collateral development were regarded as having good collateral. RESULTS: Among 400 patients, 196 (48%) were on statin therapy. Patients with good collateral score were more likely to have stable angina pectoris as clinical presentation (P<0.001), and were on statin therapy (P=0.001), and have multivessel disease (P=0.003). Statin therapy for less than 3 months had no effect on collateral development (P=0.19); however, patients who were on statin therapy for more than 3 months had significantly better collateral development (P=0.002). Statin therapy had no effect on coronary collateral development in patients having <10 mg atorvastatin-equivalent dose (P=0.13); however, patients having > or =10 mg atorvastatin-equivalent dose had better collateral development (P<0.001). Diabetes mellitus was the only negative predictor for coronary collateral formation (P=0.03). On multivariate analysis, stable angina pectoris [odds ratio 2.88, 95% confidence interval (1.8-4.7), P<0.001], statin therapy with > or =10 mg atorvastatin-equivalent dose [odds ratio 2.06, 95% confidence interval (1.3-2.6), P<0.001] and having multivessel disease [odds ratio 1.86, 95% confidence interval (1.16-3), P=0.01] were found to be associated with rich collateralization. CONCLUSION: Statin therapy (> or =10 mg atorvastatin-equivalent dose), stable angina pectoris and having multivessel disease are associated with enhanced coronary collateral development in patients with advanced coronary artery disease.

Collateral Circulation↗

PubMed2006

Isolated office hypertension: association with target organ damage and cardiovascular risk indices.

BACKGROUND: Isolated office hypertension (IOH) has been accepted as a benign condition by some researchers, whereas others believe that it is associated with cardiovascular abnormalities and increased cardiovascular risk. The aim of this present study was to evaluate the effects of IOH on target organ damage and cardiovascular risk indices. METHODS: Arterial blood pressure (BP) measured in the office and by 24-hour ambulatory blood pressure measurement (ABMP), carotid intima-media thickness (CIMT), left ventricular mass index (LVMI), cardiothoracic index (CTI), duration of QTc, 24-hour microalbuminuria, fibrinogen, C-reactive protein (CRP), total cholesterol, low-density-lipoprotein (LDL) cholesterol, high-density-lipoprotein (HDL) cholesterol and triglyceride levels were evaluated. Thirty-three subjects with IOH (office BP > or = 140/90 mmHg and daytime ambulatory BP <135/85 mmHg), 17 patients with sustained hypertension (office BP > or = 140/90 mmHg and daytime ambulatory BP > or = 135/85 mmHg), and 17 normotensive control subjects were recruited in the study. The three groups were matched for age, sex and body mass index. RESULTS: CIMT was greater in patients with IOH than in normotensive subjects, and it was significantly lower than that of sustained hypertension patients. Significantly higher LVMI was determined in subjects with IOH compared to normotensive subjects. CTI, QTc, microalbuminuria, fibrinogen, CRP, total cholesterol, LDL cholesterol, HDL cholesterol and triglyceride levels did not differ significantly among the three groups. CONCLUSIONS: IOH causes significant target organ damage and should not be regarded as a benign condition.

Blood Pressure↗

PubMed2004

Effects of TSH-suppressive therapy on cardiac morphology and function: beneficial effects of the addition of beta-blockade on diastolic dysfunction.

OBJECTIVE: To investigate the effects of long-term levothyroxine (LT4) suppressive therapy on the heart and the effects of beta-blockade on cardiac functions. DESIGN: Twelve female patients receiving LT4, selected from a group of patients with TSH levels of 0.1-0.4 microU/ml, were evaluated. The control group consisted of 11 healthy subjects and 12 patients with TSH levels <0.05 microU/ml. METHODS: Cardiac evaluation consisted of a 12-lead electrocardiogram and an echocardiographic study. Left ventricular mass index (LVMI), isovolumetric relaxation time (IVR), left ventricular end systolic (LVESD) and diastolic diameters, early (VE) and late (VA) diastolic flow velocities and fractional shortening were evaluated. Exercise capacity was assessed with a bicycle ergometer. Both work load and maximal exercise time were measured. Atenolol was given to the patient group at a dosage of 50 mg/day for 3 months and evaluations were repeated. RESULTS: On basal evaluations, LVMI (96+/-17 vs 78+/-21 g/m(2)) and IVR (101+/-9 vs 91+/-4 ms) were found to be increased in the patients taking LT4 (P<0.01). LVESD was also lower than controls (P<0.05). A decrease in VE and an increase in VA were also observed in the patients (P<0.01). IVR decreased after atenolol (92+/-10 vs 101+/-9 ms, P<0.05). LVMI decreased and VE and VA improved but did not reach statistical significance after beta-blockade. Baseline work load and maximal exercise duration were significantly lower in the patients and improvements were observed after atenolol treatment. CONCLUSIONS: These results indicated that cardiac dysfunction may occur even when TSH is suppressed to 0.1-0.4 microU/ml with LT4. beta-blockade improved the cardiac functions.

Adrenergic beta-Antagonists↗

PubMed2004

Tumour necrosis factor-alpha in diastolic dysfunction.

BACKGROUND: Active relaxation develops as a result of sequestration of calcium into the sarcoplasmic reticulum, and is controlled mainly by sarcoplasmic reticulum calcium ATPase (SERCA) and phospholamban.Tumour necrosis factor-alpha (TNF-alpha) downregulates both of these proteins, so it may play a role in the development of abnormal relaxation. However, a possible relationship between TNF-alpha and diastolic dysfunction has not been sufficiently evaluated in vivo. We investigated whether circulating levels of TNF-alpha increased in patients with relaxation abnormality. METHODS: Forty hypertensive patients with normal left ventricular systolic function were enrolled in the study. Age-adjusted values of echocardiographically measured mitral inflow velocities, E-wave deceleration time and isovolemic relaxation time were used to define normal and abnormal relaxation. Twenty of the patients (mean age 59.2 +/- 10.6) had a relaxation abnormality (group I), and the twenty other patients (mean age 45.9 +/- 7.9) had a normal diastolic function (group II). TNF-alpha levels were measured by ELISA. RESULTS: There were no significant differences between the two groups in terms of interventricular septal thickness, posterior wall thickness, left ventricular mass, ejection fraction, plasma creatinin level, and medication. Patients with a relaxation abnormality were older than those with a normal diastolic function (p < 0.001). TNF-alpha levels were similar in both groups (62.1 +/- 46.0 pg/ml for group I, and 48.7 +/- 51.4 pg/ml for group II, p = 0.089). CONCLUSION: In this preliminary study, we demonstrated that TNF-alpha levels did not increase in patients with a relaxation abnormality. However, we think that a possible relationship between TNF-alpha and diastolic dysfunction should be clarified by further studies involving a larger number of patients with a wider spectrum of diastolic dysfunction.

Calcium-Binding Proteins↗

PubMed2003

Comparison of clopidogrel versus ticlopidine for prevention of minor myocardial injury after elective coronary stenting.

We searched a randomized, double-blinded, prospective study that compared the effectiveness of clopidogrel versus ticlopidine for prevention of minor myocardial injury (MMI) and major clinical events (MCEs) after elective coronary stenting. A total of 158 consecutive patients (98 male, 60 female patients with a mean age of 59.3+/-5.4 years) were divided into two arms based on treatment with thienopyridines: group I, clopidogrel 1 x 300 mg as a loading dose, and 1 x 75 mg per day thereafter, group II, ticlopidine 2 x 250 mg daily. Both thienopyridines were started on the same day as stent placement. Cardiac troponin T (cTnT) was measured immediately before and 12 h after the procedures. All patients were followed-up during the hospital stay (6+/-2 days) with respect to MMI and MCEs. The increase frequency and the amount of cTnT level in group I was found significantly lower compared with group II (5 vs.15; P<0.01; 0.38+/-0.11 vs. 0.44+/-0.12 ng/ml; P<0.001, respectively). Patients with elevated cTnT levels more likely to have C type lesion (P<0.004). Though there was a trend toward increased major clinical events rate in group II than those of group I, the statistical difference was not different (4 vs. 1.3%; P>0.05). The present study showed that the combination of clopidogrel and aspirin was more effective than the combination of ticlopidine and aspirin in decreasing the rate of MMI.

Aged↗

PubMed2002

Assessment of left ventricular diastolic function with Doppler tissue imaging: effects of preload and place of measurements.

Mitral inflow velocities are widely used for the evaluation of left ventricular (LV) diastolic function. However, they are closely affected by other factors such as preload. The purpose of this study was to evaluate the usefulness of tissue Doppler velocities obtained from the mitral annulus for the evaluation of ventricular relaxation in patients under different loading conditions. We also evaluated the effect of preload at different sides on the mitral annulus. The study population consisted of 62 consecutive patients (38 male, 24 female with a mean age of 42 +/- 13 years) who have undergone hemodialysis. Both mitral inflow velocities (E wave, A wave, E wave deceleration time and isovolumetric relaxation time) and mitral annulus tissue Doppler velocities (E', A') from the septal, lateral, anterior, posterolateral and inferior sides of the mitral annulus were measured immediately before and after hemodialysis. Mitral inflow E and A wave velocities and E/A ratio decreased significantly (p < 0.001, p = 0.007, p < 0.001, respectively) after hemodialysis. Mitral annulus E' wave velocities and E'/A' ratios obtained from five different sides of the annulus also changed significantly (p < 0.001 for all); however, there was no change in the A' wave velocity (p > 0.05 for all) after hemodialysis. The decrease in E wave and E/A ratio in mitral inflow measurements and E' velocities and E'/A' ratios in tissue Doppler measurements were correlated with the amount of fluid extracted (for mitral inflow E wave, r = 0.392, p = 0.002 and E/A ratio, r = 0.280 and p = 0.027; for lateral side E', r = 0.329, p = 0.009 and E'/A' ratio, r = 0.286, p = 0.04; for septal side E', r = 0.376, p = 0.003 and E'/A' ratio, r = 0.297, p = 0.019; for anterior side E', r = 0.342, p = 0.007 and E'/A' ratio, r = 0.268, p = 0.035; for posterolateral side E', r = 0.423, p = 0.001 and E'/A' ratio, r = 0.343, p = 0.007; and for inferior side E', r = 0.326, p = 0.01 and E'/A' ratio, r = 0.278, p = 0.029). We conclude that mitral annular velocities obtained by tissue Doppler are preload dependent parameters for the evaluation of LV diastolic function.

Adult↗

PubMed2002

Effect of direct stent implantation on minor myocardial injury.

UNLABELLED: This nonrandomized study evaluated the incidence of minor myocardial injury (MMI) in prospectively selected patients with simple lesion morphology and class II stable angina undergoing stenting with or without predilatation. METHODS: A total of 154 patients were divided into two arms based on the stenting technique used: direct stenting without predilatation (Group I; n = 78) and stenting with predilatation (Group II; n = 76). Cardiac troponin T (cTnT) was measured immediately before, at 12 hours and 24 hours postprocedure. The primary endpoint was the MMI in-hospital. The secondary endpoint of the study was the major clinical event (MCE) rate in-hospital and up to 6 months. RESULTS: The frequency increase in Group I was found to be significantly lower compared with Group II (5.1% vs. 21%, respectively; p < 0.007), as was the amount of cTnT release (0.28 0.04 vs. 0.51 0.12 ngr/ml at 12 hours, p < 0.001; 0.28 0.06 vs. 0.51 0.10 ngr/ml at 24 hours, p < 0.0004). No MCE was seen during the in-hospital period in both groups. Furthermore, no significant differences were found between the 2 groups with respect to MCE (12.8% vs. 18.4%, respectively; p > 0.05) at 6 months. The balloon inflation time (BIT) was significantly longer in patients with abnormal cTnT level than in those with normal cTnT level in Group II (120.3 4.7 seconds vs. 118.2 1.3 seconds; p < 0.002) but there wasn t any statistical difference in Group I (32.4 2.1 seconds vs. 30.6 2.4 seconds; p > 0.05). Furthermore, there was not any statistical difference with respect to the number of balloon inflations in patients with normal and abnormal cTnT levels in either group (1.2 0.2 inflations vs. 1.3 0.4 inflations in Group I, p > 0.05; 3.2 0.9 inflations vs. 3.0 1.4 inflations in Group II, p > 0.05). CONCLUSION: This study showed that MMI probably occurs less frequently after direct stenting.

Angioplasty, Balloon, Coronary↗