Search

Abstract Background Using the streptozotocin-induced diabetic rat model, we have recently showed that the expression and function of β1-adrenoreceptor were decreased in the diabetic rat heart. However, the effect of diabetes on expression of β-adrenoreceptors in human cardiac tissue remains undefined. Therefore, the focus of the present study was to investigate the effect of diabetes on mRNA encoding β1- and β2-ARs in human atrial tissues. Methods Right atrial appendages from five diabetic (mean age 65 ± 4.5; 4 female, 1 male) and five nondiabetic patients (mean age 56.2 ± 2.8; 4 male, 1 female) undergoing coronary artery bypass grafting were collected and assayed using reverse transcriptase-polymerase chain reaction (RT-PCR) for their mRNA content. No patient from these two groups suffered from acute myocardial infarction and/or failure. All diabetic patients received insulin for at least two years and had been diagnosed as diabetics for at least five years. Results When compared with levels in nondiabetics, steady state levels of mRNA encoding β1-adrenoreceptor decreased by 69.2 ± 7.6 % in diabetic patients while β2-adrenoreceptor mRNA decreased by 32.2 ± 5.5 % (p < 0.001). Conclusions Our findings show a decreased expression of β1- and β2-adrenoreceptors in human diabetic atrial appendage.

Objective: We examined the fate of intact vertical vein during long-term follow-up and its effects on ventricular functions., Methods: Eighty one patients with all types of total anomalous pulmonary venous connection (TAPVC) were operated. Thirty-one patients with supracardiac type TAPVC were examined in our retrospective cohort study. Groups were evaluated with respect to left ventricle area, volume, end-systolic, end diastolic diameter, early and late term mortality and properties of pulmonary hypertensive crisis. Vertical vein was left open in 14 patients and it was ligated in 17 patients. Wilcoxon rank and Mann- Whitney U tests were used to compare variables between groups., Results: After mean follow up of 48±36 months, vertical vein closed spontaneously in 3 patients. Two of them were closed surgically due to elevated shunt flow and there was spontaneous closure in one patient who had the highest pulmonary artery pressure amongst others postoperatively. Preoperative left ventricular area, volume, end-systolic diameter and end-diastolic diameter values of the patients increased from 3.5± 0.9 mm(2)-2.9±0.9 mm(3)-14±5 mm-8±4.5 mm to 8±3.3 mm(2)-16±8.7 mm(3)-27±6.7 mm-17±4.8 mm at the postoperative period in Group 1, and from 6.8±3.5 mm(2)-8.4±8.7 mm(3)-15±6.4 mm-9±5.3 mm to 7.4±5.2 mm(2)-16±1.7 mm(3)-21.7±5 mm-13.5±4.1 mm in Group 2, respectively (p=0.02, p=0.039, p=0.054, and p=0.07, respectively)., Conclusion: Vertical vein remains intact in most of the patients and may be closed spontaneously in patients with elevated pulmonary resistance. Intact vertical vein both decompresses the left ventricular cavity in patients with decreased left ventricular compliance until the ventricular muscle adapts to new workload and improves ventricular functions on long term follow up. Therefore, we conclude that vertical vein should be left open in selected patients.

Blunt cardiac injury may result in traumatic ventricular septal defect (VSD) in the pediatric population, but presence of postinfarction VSD with accompanying coronary artery thrombosis has not been reported in the literature thus far. We present a seven-year-old patient who underwent surgery for posttraumatic VSD closure and bypass grafting of thrombotic left anterior descending coronary artery (LAD) occlusion following blunt chest trauma. A high index of suspicion and early use of the appropriate imaging studies are essential for diagnosis and surgical treatment of this condition.

Background: The aim of this study was to assess the relation between plasma B-type natriuretic peptide (BNP) levels and right ventricular function evaluated by tissue Doppler imaging (TDI) in patients after repair of tetralogy of Fallot (ToF)., Methods: Twenty-five patients with a mean age of 14.1 +/- 4.4 years who underwent repair of ToF at a mean age of 4.9 +/- 5.1 years enrolled in this study. The control group consisted of 29 healthy children at a mean age of 13.1 +/- 2.8 years. The right ventricle and pulmonary regurgitation (PR) were assessed by two-dimensional echocardiography and color Doppler. Blood samples for BNP levels were taken and TDI was performed at rest., Results: Plasma BNP levels were significantly higher in patients than in controls (28.3 +/- 24.1 vs. 7.4 +/- 2.3 pg/mL, P = 0.0001). The myocardial performance index (MPI) (1.08 +/- 0.35 vs. 0.58 +/- 0.11, P = 0.0001) was higher and isovolumic acceleration (IVA) (3.1 +/- 0.7 vs. 5.4 +/- 1.0 m/s(2), P = 0.0001) was lower in patients. The correlations were also significant between the degree of PR and MPI (r = 0.7, P = 0.0001) and also IVA (r =-0.7, P = 0.0001). The correlations were also significant between the BNP level and MPI (r = 0.6, P = 0.0001), IVA (r =-0.4, P = 0.002) and the degree of PR (r = 0.6, P = 0.0001)., Conclusion: As a result, plasma BNP level increases in patients with ToF and both MPI and IVA from the right ventricular basal segments might be used to assess the right ventricular function.

The benefits of a baffle fenestration in essentially high-risk Fontan patients have been demonstrated. Described here is the use of a new fenestration between the left atrial appendage and the left superior vena cava after Kawashima operation in a patient with a double-outlet right ventricle with hypoplastic left ventricle, left atrial isomerism, bilateral superior vena cavae with no bridging vein, an interrupted inferior vena cava, and continuation of the hemiazygos vein to the left superior vena cava.

Impairment of right ventricular functions, especially due to chronic pulmonary regurgitation (PR), is a well-known entity in patients with tetralogy of Fallot (ToF) after repair. The aim of this study was to examine the relation between B-type natriuretic peptide (BNP) levels and right ventricular dysfunction by cardiopulmonary exercise test (ET) in patients after repair of ToF. Twenty-five patients with a mean age of 14.1 +/- 4.4 years at follow-up who underwent repair of ToF at a mean age of 4.9 +/- 5.1 years and 29 age- and sex-matched healthy children at a mean age of 13.1 +/- 2.8 years were enrolled in this study. Plasma BNP levels were measured at baseline and at maximal exercise. The volume of right ventricle (RV) and the degree of PR were assessed by two-dimensional echocardiography and color Doppler. Plasma BNP levels were significantly higher in patients with ToF than in controls (28.3 +/- 24.1 vs 7.4 +/- 2.3 pg/mL, p = 0.0001). Exercise was associated with increased plasma BNP levels in both groups. A greater increase in BNP was noted in patients with ToF than in controls (37.6 +/- 27.5 vs 11.3 +/- 4.5 pg/mL, p = 0.0001). Forced vital capacity (FVC%) (84.9 +/- 16.9 vs 98.4 +/- 18.2, p = 0.01) and forced expiratory volume during the 1st second (FEV1%) (91.5 +/- 19.3 vs 103.8 +/- 16.1, p = 0.02) were decreased, exercise duration (ED) (10.1 +/- 1.9 vs 11.4 +/- 1.7 min, p = 0.02), maximum heart rate (HRmax) (171.2 +/- 18.9 vs 186.4 +/- 13.9 /min, p = 0.004), and maximum oxygen uptake (VO(2)max) (1.56 +/- 0.53 vs 2.1 +/- 0.6 L/min, p = 0.007) were lower in patients with ToF. There were significant correlations between the degree of PR and ED (r =-0.3, p = 0.009), HRmax (r =-0.4, p = 0.001), and VO(2)max (r =-0.4, p = 0.001). The correlations were significant both before and after exercise, being more pronounced after exercise between BNP level and the degree of PR (r = 0.6, p = 0.0001). As a result, the severity of PR has a negative influence on right ventricular functions and there is significant relation between right ventricular functions and exercise capacity after repair of tetralogy of Fallot.

Objective: Life-threatening arrhythmias and sudden death remain to be serious late complications after correction of tetralogy of Fallot. The aim of this study was to detect ventricular arrhythmia incidence and to find out the relationship between ventricular arrhythmia and the transannular and infundibular patch repair techniques to correct tetralogy of Fallot. That is still unpredictable exactly., Methods: Thirty-nine patients with mean age of 12.1+/-3.1 years were studied prospectively for 7.1+/-2.1 years after operation. They were all investigated with electrocardiography, echocardiography, treadmill and Holter monitorization. Right ventricular functions, exercise capacity and arrhythmia patterns were assessed. Lown criteria were used for grading the arrhythmia patterns. QRS duration, QT dispersion and QT dispersion indexes were calculated., Results: Follow up time was 5 to 13 years in both groups. All QT dispersion times and indexes were within normal ranges and there were no differences between two groups. Holter and treadmill studies did not reveal during any ventricular arrhythmia risk in the study and control groups., Conclusion: Seven years of follow-up after correction of tetralogy of Fallot revealed that transannular patch reconstruction is not a cause of tendency for ventricular arrhythmia according to Lown criteria, QT dispersion, QT dispersion indexes and QRS duration do support the results of previous studies.

Background: Recently, several temporary multisite pacing methods have been developed for prevention of postoperative atrial fibrillation (AF)., Hypothesis: In this study, we evaluated the effect of triple-site temporary triggered pacing in the AAT mode on the development of AF in patients undergoing coronary artery bypass graft (CABG) at high risk for developing postoperative AF., Methods: A total of 70 patients undergoing CABG were randomly assigned either to pacing group (study group, n = 35 patients) or to no pacing group (control group, n = 35 patients). The external pacemaker was programmed to pace at the atrial triggered mode at a lower rate of 40 beats/min for 4 days., Results: Atrial fibrillation, defined as lasting > 30 s, occurred in 4 patients (11.4%) in the study group and in 16 patients (45.7%) in the control group (p = 0.003). Sustained AF, defined as AF lasting > 10 min, also was observed less frequently in the study group than in the control group (11.6 vs. 37.1%, p = 0.024). Triple-site triggered atrial pacing was observed to reduce the incidence of AF by 75% and the incidence of sustained AF by 69%., Conclusions: We believe that multiple-site temporary pacing in the triggered mode is an effective way of preventing postoperative AF. This technique may be used especially in patients at high risk of developing AF.

Objective: Rheumatic heart disease is still a major health problem in developing countries. The impact of coronary artery disease (CAD) on or its relation to rheumatic fever is not well established. We aimed to evaluate the prevalence of CAD and atherosclerotic risk factors in patients who underwent valvular surgery due to rheumatic heart disease., Methods: The records of 346 patients who had undergone rheumatic valvular surgery in a university hospital between 1996 and 2002 were evaluated., Results: Coronary angiography was performed in 218 (63%) patients, of whom 41 (18.8%) had CAD. The mean age of the patients having CAD and normal coronary arteries were 57.3 and 50.5 years respectively (p<0.001). In the study population patients with CAD had significantly increased prevalence of diabetes mellitus (14.6% vs. 4.5%; p=0.02), hypertension (36.6% vs. 16.4%; p=0.003), smoking (51.2% vs. 23.2%; p=0.001) and family history of CAD (39.5% vs. 20.0%; p=0.01) compared to patients with normal coronary arteries. However, the prevalence of dyslipidemia was similar in both groups (45.9% vs. 36.4%; p=0.1)., Conclusion: These findings suggest that coronary artery disease prevalence in rheumatic valvular disease patients is similar to the normal population of same age. In cases where invasive assessment of valvular lesions is not indicated we suggest coronary angiography to be performed only in patients having clinical suspicion of CAD or multiple risk factors.

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.

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.

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.

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.