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S Aşlamaci

Publications and source records attributed to S Aşlamaci.

10 recordsLinked to original sources

Evaluation of the potential role of echocardiography in the detection of allograft rejection in heart transplant recipients.

PURPOSE: Our objective was to determine the most relevant systolic and diastolic echocardiographic parameters to detect left ventricular (LV) dysfunction associated with allograft rejection among heart transplant recipients. PATIENTS AND METHODS: Seven consecutive recipients underwent serial echocardiographic studies with two-dimensional spectral Doppler and tissue Doppler (TD) according to our institutional protocol. Results were compared with clinical status and endomyocardial biopsies (EMB) whenever available. RESULTS: The time since transplantation was 22 to 850 days. Patient no. 2 had a biopsy-proven acute rejection at the 11th week which was associated with decreased TD velocities, ejection fraction (EF), and stroke volume (SV), as well as increased pericardial effusion and posterior wall thickness. Interestingly, changes in TD parameters preceded those in EF and SV. However, similar but less remarkable changes in TD velocities, EF, SV, pericardial effusion, and posterior wall thickness also occurred during other events, such as systemic infection and immediate postoperative hemodynamic compromise despite no rejection. A biopsy performed 7 months later in a patient with a previous rejection episode due to a relatively low EF and SV as well as increasing pericardial effusion with normal TD velocities revealed no rejection. CONCLUSIONS: These data suggest that echocardiographic findings, although not specific for acute rejection, may play a potential role as a screening test to exclude rejection in heart transplant recipients.

Adult↗

The comparison of the responsiveness of human isolated internal mammary and gastroepiploic arteries to levcromakalim: an alternative approach to the management of graft spasm.

AIMS: We studied the effectiveness of levcromakalim, a potassium channel opener (KCO), in the prevention and reversal of spasm in arterial grafts used in coronary artery bypass operations, namely, internal mammary artery (IMA) and gastroepiploic artery (GEA). METHODS: Spasm was mimicked in vitro in arterial rings from 109 patients by increasing the vascular tension with noradrenaline, the thromboxane analogue U46619, endothelin-1 and K+. RESULTS: GEA displayed considerably higher contractile force to these agents than IMA. Pretreatment with levcromakalim depressed significantly the maximal contractile responses (either absolute or relative) to noradrenaline and U46619 but did not affect those of endothelin-1 and K+ in both of the arteries. Sensitivities (to all agents, except to endothelin-1) decreased significantly after levcromakalim. In experiments evaluating the antispasmodic activity of levcromakalim, a higher relaxant capacity was observed in GEA than IMA (for K+ contraction; IMA: 31.32 +/- 3.83%, n= 13 vs GEA: 98.01 +/- 0.71%, n=7, P<0.05). This different activity of levcromakalim between two arterial grafts was apparent even when GEA rings were contracted to higher force (g) than that of IMA (for K+ contraction; GEA: 72.56 +/- 4.96%, n = 7). Responses to levcromakalim were similar in IMA and GEA when endothelin-1 was used as the spasmogenic agent (IMA: 80.98 +/- 4.85%, n=10 vs GEA: 91.93 +/- 3.17%, n=7, P>0.05). CONCLUSIONS: Our results provide evidence that levcromakalim may have a therapeutic value in the treatment of spasm of coronary artery bypass grafts, especially GEA.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗

Endothelial function of human gastroepiploic artery in comparison with saphenous vein.

OBJECTIVE: Endothelial function is one of the important determinants of patency rate of a graft material used in coronary revascularisation. The aim of this study was to compare the endothelial reactivity of human gastroepiploic artery versus saphenous vein in response to various vasoactive substances. METHODS: Gastroepiploic artery and saphenous vein rings were mounted in an organ bath containing Krebs-Ringer bicarbonate solution aerated with 95% O2 and 5% CO2 at 37 degrees C. Endothelium dependent responses of acetylcholine, histamine, and bradykinin were examined on the precontracted rings of the vessels. The sensitivity of these two graft materials to the potent vasoconstrictor agent endothelin-1 was also compared. RESULTS: Acetylcholine, histamine, and bradykinin caused dose dependent relaxations in saphenous vein and gastroepiploic artery rings. These agonists were more effective in producing endothelium dependent relaxations in the artery than in the vein. Endothelium removal and pretreatment with nitro-arginine abolished the relaxations completely in saphenous vein but not in gastroepiploic artery, depending on the relaxing agent used. On the other hand, both graft materials showed nearly equal sensitivity to endothelin-1 (EC50 values; 3.5 x 10(-9) M in the vein versus 6.4 x 10(-9) M in the artery, p = NS) which was not affected by endothelium removal. CONCLUSIONS: Gastroepiploic artery exhibited more pronounced relaxation and a different response profile to endogenous vasoactive substances than saphenous vein. The demonstration of higher capacity of the artery to release vasoactive substances in response to various endogenous agents shows that gastroepiploic artery may have a better long term patency rate than saphenous vein.

Acetylcholine↗

Aortico-left ventricular tunnel.

A 10-year-old boy with aortico-left ventricular tunnel, a very unusual congenital cardiovascular malformation, is presented. Closure of both orifices of the tunnel by round teflon patches is recommended. We think this surgical technique is superior to closure of these openings by primary sutures only, which can result in stretching and distortion of the aortic ring and leaflets leading to postoperative residual aortic regurgitation.

Adolescent↗

The role of pulmonary artery anatomy in repair of tetralogy of Fallot.

Pulmonary artery anatomy is the key factor that determines the type of surgical treatment required in tetralogy of Fallot. Despite the fact that routine primary repair is now done on infants, inadequate pulmonary artery size can dictate the need for staged surgical repair in even the oldest age groups. From October 1986 to October 1998, 361 patients at our clinic underwent surgery to correct tetralogy of Fallot. A total of 292 cases were treated with primary repair, 69 surgeries were palliative, and 30 of these 69 underwent corrective surgery. The Nakata index was used as a pulmonary artery index (PAI), and PAI< 200 was the criterion for requirement of two-stage repair. Of the 30 patients that underwent staged repair, the Blalock-Taussig shunt (BTS) procedure was used in 24; the remaining six patients had right ventricular outflow tract reconstruction (RVOTR). The mean age of all the palliative surgery patients was 3.4 years (range 6 months to 11 years), and of those who received corrective surgery was 5.5 years (range 2-12 years). These patients' PAI values were 181 +/- 37.5 mm2/m2 and 359 +/- 130.7 mm2/m2, respectively. The period between the two operations ranged from two months to four years. Mortality rates were 2.8 percent for palliative surgery as a whole, 4.1 percent for primary repair, and 16.6 percent for staged repair. Our policy with regard to corrective surgery for tetralogy of Fallot is to do primary repair regardless of a patient's age and weight, except in cases where the pulmonary artery anatomy is appropriate for the patient's body size.

Adolescent↗

An unusual late complication following surgical repair of tetralogy of Fallot.

A case is presented of extrusion of right ventricular outflow tract patch material through a mediastino-cutaneous fistula occurring five years after repair of tetralogy of Fallot. The focus of the mediastinal infection was an infected epicardial pacemaker electrode placed at the time of initial surgery. Subsequent echocardiographic studies showed minimal right ventricular outflow tract or pulmonary arterial dilatation, and, with no further surgery, the child is well after two and a half years follow-up.

Blood Vessel Prosthesis↗