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Tevfik Demir

Publications and source records attributed to Tevfik Demir.

14 recordsLinked to original sources
PubMed2006

Patency or recanalization of the arterial duct after surgical double ligation and transfixion.

OBJECTIVE: The frequency of residual shunting or recanalization was investigated in patients in whom a persistently patent arterial duct had been doubly ligated and transfixed during surgical closure. METHODS: We investigated in retrospective fashion for any residual shunting 325 patients who, between January 1990 and December 2004, had undergone surgical double ligation and transfixion of a persistently patent arterial duct. Shunting was discovered in 10 patients, of whom four male and six female. RESULTS: Of those with residual shunting. 4 patients had initially exhibited only persistent patency of the duct, while the other 6 had associated mild cardiac lesions. The mean age at operation was 5.5 years, with a range from 0.5 to 17.9 years. Postoperatively, the mean period for detecting the residual shunt was 22.8 months, with a range from 2 days to 72 months. The frequency of residual shunting amongst our patients, therefore, was 3.1%. We detected the residual shunt by colour-flow Doppler mapping in all patients, although a continuous murmur was heard in only one patient on physical examination. CONCLUSION: Our findings suggest that clinical sensitivity of detecting residual shunting subsequent to surgical closure of the persistently patent arterial duct is low, and hence that colour-flow Doppler interrogation should be a part of follow up. Residual shunting, or recanalization, may occur even after double ligation and transfixion of the duct. Since the residual flow may emerge after months, or even years, follow-up is needed for longer periods.

Adolescent↗
PubMed2006

Echocardiographic follow-up of children with isolated discrete subaortic stenosis.

This study evaluates the progression of stenosis, onset and progression of aortic regurgitation (AR), and the results of surgical outcomes in children with isolated discrete subaortic stenosis (SAS). The medical records of 108 patients (mean age, 5.5 +/- 3.8 years; range, 3 days to 18 years) with isolated discrete SAS were reviewed. Patients with lesions other than AR were excluded. Very mild stenosis was defined as Doppler peak systolic instantaneous gradient (PSIG) less than 25 mmHg, mild stenosis as 25-49 mmHg, moderate stenosis as 50-75 mmHg, and severe stenosis as more than 75 mmHg. Seventy-eight of 108 patients were followed for 2 months to 14 years (mean, 4.8 +/- 3.7 years; median, 5 years) with medical treatment alone. In these patients, the mean PSIG at last echocardiogram was higher than the mean PSIG at initial echocardiogram (39 +/- 19 vs 31 +/- 12 mmHg, respectively; p < 0.001). Among 24 patients with very mild stenosis at initial echocardiogram, 10 had mild and 2 had moderate stenosis after a mean period of 5.6 years. Among 46 patients with mild stenosis at initial echocardiogram, 11 had moderate and 5 had severe stenosis after a mean period of 4.1 years. Only 1 patient among the 8 patients with moderate stenosis at initial echocardiogram had severe stenosis after a mean period of 2.7 years. Thirty-nine patients (50%) had AR (13% trivial, 33% mild, and 4% moderate) at initial echocardiogram. After a mean period of 4.8 years, 77% of the patients had AR (10% trivial, 53% mild, 9% mild-moderate, and 5% moderate). Twenty-four patients underwent surgery. Preoperatively, mean Doppler PSIG and AR incidence were 64 +/- 17 mmHg and 91% (22/24), respectively. The mean Doppler PSIG was 30 +/- 19 mmHg and AR was present in all of the patients a mean period of 4.1 years after surgery. Two patients underwent reoperation for recurrent SAS and AR. Patients with very mild or mild stenosis may be followed noninvasively every year. One patient of the 8 patients with moderate stenosis progressed to severe stenosis, and moderate AR developed in 2 patients after a mean of 2.7 years. We recommend that patients with moderate stenosis undergo careful evaluation to determine whether surgery is necessary due to the severity of stenosis and AR.

Adolescent↗
PubMed2006

Echocardiographic follow-up of congenital aortic valvular stenosis.

We investigated the morphology of the stenotic aortic valve, the progression of the stenosis, and the onset and progression of aortic regurgitation (AR) in patients with congenital aortic valvular stenosis (AVS). The medical records of 278 patients with AVS were reviewed, with the patients with concomitant lesions besides AR excluded. Very mild aortic stenosis was defined as a transvalvular Doppler peak systolic instantaneous gradient (PSIG) less than 25 mmHg, mild stenosis as 25-49 mmHg, moderate stenosis as 50-75 mmHg, and severe stenosis as more than 75 mmHg. The mean age of the patients was 4.9 +/- 4.3 years (range, 3 days to 15 years), and 203 (73%) were male. The number of the cusps was determined with two-dimensional echocardiography in 266 patients (95%): unicuspid in 3 patients (1%), bicuspid in 127 patients (48%), and tricuspid in 136 patients (51%). A total of 192 of all patients were followed for 2 months to 14.6 years (mean 4.2 +/- 3.3 years) with medical treatment alone. Among 72 patients with very mild stenosis at initial echocardiographic examination, 20% had mild, 3% moderate, and 1% severe stenosis after a mean period of 3.7 years. In 70 patients with mild stenosis at initial echocardiographic examination, 28% had moderate and 9% severe stenosis after a mean period of 5 years. Among 44 patients with moderate stenosis at initial echocardiographic examination, 36% had severe stenosis after a mean period of 3.7 years. Among 192 patients, 40% had AR (3% trivial, 28% mild, and 9% moderate) at initial echocardiographic examination. After a mean period of 4.2 years, 58% of the patients had AR (13 % trivial, 25% mild, 16% moderate, and 4% severe). There was not statistically significant difference between catheterization peak systolic gradients (47 +/- 16 mmHg) and Doppler estimated mean gradients (45 +/- 9 mmHg) (p = 0.53), whereas Doppler PSIGs (74.9 +/- 15.7 mmHg) were higher than catheterization peak systolic gradients (p < 0.0001) in 25 patients who were studied in the catheterization lab. Patients with very mild stenosis may be followed with a noninvasive approach every 1 or 2 years, and an annual follow-up is suggested for patients with mild stenosis. Nearly one-third of patients with moderate stenosis at initial echocardiographic examination had severe stenosis after a mean period of 3.7 years. Therefore, we recommend, that patients with moderate stenosis undergo noninvasive evaluation every 6 months. Doppler estimated mean gradient is very useful in predicting the need for intervention in children with AVS.

Adolescent↗
PubMed2006

Elevated thrombin activatable fibrinolysis inhibitor (TAFI) antigen levels in overt and subclinical hypothyroid patients were reduced by levothyroxine replacement.

The influence of hypothyroidism on haemostasis is an active research area. Not only bleeding tendency but also hypercoagulable states have been reported in hypothyroid patients. Decreased and increased fibrinolytic activity in hypothyroid patients has been shown in several studies. Thrombin activatable fibrinolysis inhibitor (TAFI) is an inhibitor of fibrinolysis, which has been recently isolated from human plasma. The aim of our study was to determine plasma TAFI antigen levels in overt and subclinical hypothyroidism, and to investigate the effect of levothyroxine treatment on TAFI levels. The study was performed in age- and sex-matched 30 overt hypothyroid, 30 subclinical hypothyroid patients, and 30 healthy controls. Blood samples were obtained from patients with overt and subclinical hypothyroidism before levothyroxine replacement, and one month after achieving a euthyroid state with levothyroxine. TAFI antigen levels were measured using Enzyme-Linked ImmunoSorbent Assay kits (Affinity Biologicals; Ontario, Canada). In baseline evaluation both the overt and subclinical hypothyroid groups had higher TAFI antigen levels than control group (p<0.05). High levels of TAFI antigen were correlated with the degree of thyroid failure. After achieving euthyroid state with levothyroxine replacement, TAFI antigen levels decreased significantly in patients with overt and subclinical hypothyroidism (p<0.05). Our data suggest that there are elevated plasma levels of TAFI antigen both in overt and subclinical hypothyroidism, which may be associated with hypofibrinolysis and elevated risk of thrombosis. Normalization of thyroid state by levothyroxine replacement seems to be effective in lowering of TAFI antigen levels in hypothyroidism.

Adult↗
PubMed2006

Echocardiographic follow-up of children with supravalvular aortic stenosis.

This study evaluates the course of supravalvular aortic stenosis (SVAS)-associated right ventricular outflow tract (RVOT) obstruction and the results of surgery in children. We reviewed the medical records of 24 patients diagnosed with SVAS at initial echocardiographic examination or during the following period of RVOT obstruction. Very mild SVAS was defined as a transvalvular Doppler peak systolic instantanous gradient (PSIG) less than 25 mmHg, mild stenosis as 25-49 mmHg, moderate stenosis as 50-75 mmHg, and severe stenosis as more than 75 mmHg. The mean age of the patients was 3.1 +/- 2.9 years (range, 7 days to 12.7 years), and 18 of the patients (72%) were male. Fifteen patients had Williams' syndrome. Seventeen patients (71%) were followed for a mean of 5.2 +/- 3.8 years (range, 7 months to 13.5 years). Among 17 patients with complete follow-up records, 1 (6%) had very mild, 5 (29%) mild, 3 (18%) moderate, and 3 (18%) severe aortic stenosis at initial echocardiographic examination. In a newborn patient with mild pulmonary valvular stenosis. SVAS became evident after 2 months and progressed rapidly. Supravalvular aortic stenosis was very mild in 4 patients (23%), mild in 3 (18%), moderate in 3 (18%), and severe in 7 (41%) at last echocardiographic examination. Of 17 patients who were followed, 11 (65%) had RVOT obstruction at initial echocardiographic examination. RVOT obstruction disappeared in 5 patients, regressed in 1 patient, and appeared in 1 patient over the follow-up period. Four patients underwent operation. It appears reasonable that patients with very mild and mild stenosis should be followed medically every 1 or 2 years and patients with moderate stenosis once a year. Newborns with SVAS should be followed for rapid progression of SVAS. In some patients, RVOT obstruction may disappear, and SVAS may develop in others with RVOT obstruction. Patients with RVOT obstruction (at the valvular, supravalvular, or peripheral pulmonary arterial level) should be evaluated carefully for development of SVAS at follow-up.

Aortic Stenosis, Supravalvular↗
PubMed2006

Venous and intrapericardial thrombosis: secondary to transient protein C deficiency.

We present a 2-month-old male infant with thrombosis in the superior vena cava and pericardium due to transient protein C deficiency. Protein C deficiency was related to sepsis and hepatitis-induced liver function impairment. The patient's cardiac anatomy was otherwise normal. The patient was referred to us with signs of superior vena cava syndrome. Pericardial mass was excised. Pathological examination diagnosed the mass as organized thrombus. After the operation, signs of superior vena cava syndrome totally resolved. Serial echocardiographic examinations revealed regression of thrombus in the superior vena cava. This is the first case reported in the literature with intrapericardial thrombus secondary to transient protein C deficiency.

Cardiac Surgical Procedures↗
PubMed2006

Mosaicism of a thyroid hormone receptor-beta gene mutation in resistance to thyroid hormone.

CONTEXT: Heterozygous mutations in thyroid hormone receptor-beta (TRbeta) gene are the cause of resistance to thyroid hormone (RTH) in more than 85% of families having the syndrome. In 23% of the families, TRbeta gene mutations occur de novo. Of the 141 families with RTH investigated by us, 21 (15%) had no TRbeta gene mutations detectable by sequencing from genomic DNA (gDNA) or cDNA (non-TR RTH). OBJECTIVE: The objective of the study was to investigate the genotype of a family with RTH and correlate it to the phenotype. DESIGN: The DNA was isolated from different tissues, and the sequence of the TRbeta gene was determined. Clinical studies involved the administration of incremental doses of T(3). SETTING: The study was conducted at a referral pediatric endocrinology clinic in Turkey and an academic medical center in the United States. MAIN OUTCOME AND MEASURES: Measurement included markers of thyroid hormone action and sequencing of TRbeta revealing a R338W mutation. Patients and Family: We studied two siblings with short stature, panic disorder, psychosis, and high free iodothyronine concentrations with nonsuppressed TSH and their father with similar thyroid function tests without growth or psychiatric abnormalities. RESULTS: Direct sequencing of gDNA obtained from the father's leukocytes, buccal mucosa cells, and prostate tissue showed less amplification of the mutant allele (R338W) than the normal allele as confirmed by PCR/restriction fragment length polymorphism analysis. No sequence abnormalities were detected in gDNA from fibroblasts. Similar results were found in mRNA from the leukocytes and fibroblasts. The sensitivity of various tissues to thyroid hormone was not uniform. The progeny had equal amounts of mutant and wild-type gDNA in leukocytes and skin. CONCLUSIONS: The father has a mosaicism for the R338W mutation as it was present in some cell lineages, including his germline, because it was transferred to his children but not in fibroblasts. This indicates that the mutation occurred de novo in early embryonic life. Here is the first report of mosaicism in RTH. The possibility of mosaicism should be considered in subjects with RTH without apparent mutations in the TRbeta gene.

Adult↗
PubMed2006

Hyperhomocysteinemia: a novel risk factor for erectile dysfunction.

Nitric oxide (NO), the key mediator synthesized by different NO synthase isoenzymes, plays an important role in endothelial function. It was recently shown that hyperhomocysteinemia is an important regulator of NO synthase. We investigated the role of homocysteine (Hcys) in erectile dysfunction (ED), which is associated with the defect in NO generation. Thirty-one nondiabetic patients and 33 control cases were evaluated. Patients with diabetes, coronary artery disease, vitamin B(12), or folate deficiency were excluded in the study. The International Index of Erectile Function questionnaire was used to gauge identified erectile quality. Fasting plasma glucose, total cholesterol, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, vitamin B(12), folic acid, and Hcys levels of patients were measured. Penile color Dupplex ultrasound was used to detect vascular abnormalities in nondiabetic patients with ED. Patients with ED were older than the control subjects (55.6 +/- 8.4 vs 44.5 +/- 4.7 years, respectively; P < .001). Patients with ED had higher fasting plasma glucose, total cholesterol, low-density lipoprotein cholesterol, and Hcys levels. There was a significant negative correlation between mean Hcys level and mean International Index of Erectile Function domain score (P < .001). The penile color Doppler ultrasound findings showed that there was a negative significant correlation between mean Hcys level and the 1st, 5th, and 10th minute's peak-systolic velocity. Logistic regression analysis revealed that age and Hcys levels were the main determinants in ED. Hyperhomocysteinemia, known to be an important risk factor in endothelial dysfunction, seems to be an important determinant in ED. These data suggest that slightly elevated Hcys levels are significantly related with arterial and probably endothelial dysfunction in patients with ED.

Adult↗
PubMed2006

Prevalence of erectile dysfunction in patients with metabolic syndrome.

AIM: We wished to investigate the relationship between metabolic syndrome and erectile dysfunction (ED). MATERIALS AND METHODS: A total of 268 patients were included in this study. All of the patients were asked to fill in an International Index for Erectile Function (IIEF) questionnaire. The presence of metabolic syndrome was determined when any three or more of the five risk factors were present according to the National Cholesterol Education Program (NCEP) Adult Treatment Panel (ATP)-III. The relationship between risk factor for metabolic syndrome and ED status was determined according to logistic regression analysis. RESULTS: Eighty-nine patients (33%) constituted the metabolic syndrome group. IIEF-EF domain scores of patients with and without metabolic syndrome were 17.7 +/- 7.9 and 21.7 +/- 7.5, respectively (P < 0.001). Seventy-four percent of patients with metabolic syndrome and 50% of patients without metabolic syndrome had ED (P < 0.001; odds ratio 2.9; 95% CI 1.7-5.0). Erectile function domain scores significantly decreased as the number of metabolic risk factors increased (P < 0.001). Patients with the risk factor of fasting blood glucose (FBG), waist circumference (WC), or hypertension (HT) had lower erectile function domain scores than the patients with other metabolic risk factors. Logistic regression analysis revealed that FBG and WC were the most important criteria for ED. CONCLUSIONS: Metabolic syndrome seems to be a potential risk factor for ED. We recommend patients with metabolic syndrome should be questioned about ED, and WC measurement might take part in the evaluation of ED.

Erectile Dysfunction↗
PubMed2003

Plasma levels of free tissue factor pathway inhibitor in patients with various thyroid disorders.

Various coagulation abnormalities occur in thyroid disorders and its range may vary from subclinical laboratory abnormalities to clinically significant disorders of coagulation. Tissue factor pathway inhibitor (TFPI), which inhibits the initial reaction of tissue factor mediated coagulation pathway, is reported to be increased in patients with Graves disease (GD) in one study. Hyperthyroid (n=10), hypothyroid (n=10) and subclinical hypothyroid (n=10) patients and control cases (n=16) were evaluated for free and total tissue factor pathway inhibitor (tTFPI), plasminogen activator inhibitor-1 (PAI-1) and tissue plasminogen activator (tPA) levels in disease and euthyroid states. Free TFPI levels were significantly higher in hyperthyroid patients compared with the control group and subclinic hypothyroid patients (p<0.001), but not with hypothyroid patients (p>0.05). After the euthyroid state was obtained in the hyperthyroid group, the levels of total TFPI (p<0.05), free TFPI (fTFPI) (p<0.005), t-PA (p<0.005) and PAI-1 (p<0.02) decreased significantly. In hyperthyroid patients, there was a strong correlation between thyroid functions and free TFPI levels. In conclusion, we hypothesize that coagulation abnormalities seen in thyroid disorders cannot be explained directly with the impaired fibrinolytic activity but also with the elevated fTFPI levels. Both increased plasma fTFPI and PAI-1 levels could be markers of the peripheral activity of thyroid hormones.

Adult↗
PubMed2003

A premature newborn with vesiculobullous skin lesions.

UNLABELLED: Although the rate of congenital syphilis is declining in Western Europe and in the USA, a significant increase is observed in the developing countries. In this contribution, a newborn with cutaneous manifestations of congenital syphilis is presented. CONCLUSION: Pediatricians should be attentive when confronted with vesiculobullous skin lesions in a newborn, and congenital syphilis should be considered in the differential diagnosis.

Humans↗
PubMedDate not supplied

Off pump repair of aortic arch anomalies with concomitant intracardiac defects via anterior approach.

BACKGROUND: The authors evaluated the surgical treatment of aortic arch anomalies associated with intracardiac pathologies, through median sternotomy on beating heart without using cardiopulmonary bypass (CPB). METHODS: A consecutive series of 10 patients with aortic coarctation were operated upon. Median age at repair was 3.5 months (range, 5 days to 72 months), median weight was 4 kg (range, 2.2 to 30 kg). All aortic obstruction repairs were done via midsternotomy without using CPB and it is used only for repair of intracardiac defects. The aortic reconstruction included resection and end-to-side anastomosis in six patients and pulmonary autograft patch aortoplasty in four patients. RESULTS: There was no operative mortality. Mean follow-up value was 17.6 +/- 8.07 months. There was no restenosis. CONCLUSION: Most of the aortic coarctation and interrupted aorta type A can be well-treated surgically through median sternotomy without using CPB. Thus, the need for profound hypothermia and circulatory arrest and its potential neurological and other side effects are removed and CPB is reserved only for associated intracardiac defects, if present.

Anastomosis, Surgical↗