Hashim Abdul-Khaliq

Relation between right ventricular enlargement, QRS duration, and right ventricular function in patients with tetralogy of Fallot and pulmonary regurgitation after surgical repair

OBJECTIVE In patients with repaired tetralogy of Fallot, to examine (1) a possible relation between right ventricular enlargement and QRS prolongation, and (2) the effect of right ventricular enlargement caused by pulmonary regurgitation on the right ventricular ejection fraction, evaluated by three dimensional echocardiography, and global function, evaluated by the myocardial performance index. DESIGN AND PATIENTS 40 patients with repaired tetralogy were studied. Right ventricular volumes were derived from three dimensional echocardiographic data after this method had been validated by comparison with magnetic resonance imaging in 21 patients. Ejection fraction was calculated from end diastolic and end systolic volumes. The Doppler derived myocardial performance index was measured in all patients. Measured data were correlated with QRS duration. SETTING Tertiary cardiac centre for congenital heart disease. RESULTS There was good agreement between three dimensional echocardiographic and magnetic resonance assessment of right ventricular volumes and ejection fraction. The z score of the right ventricular end diastolic volume and ejection fraction of all patients was 1.35 and −4.15, respectively. Patients with severe pulmonary regurgitation had a lower right ventricular ejection fraction (p < 0.01) and an increased myocardial performance index (p < 0.01) compared with patients with mild to moderate pulmonary regurgitation. The correlation between ejection fraction and right ventricular end diastolic volume wasr = −0.35 (p < 0.05). The mean (SD) QRS duration was 131.89 (25.69) ms, range 80–180 ms. The correlation between QRS duration and right ventricular end diastolic volume wasr = 0.6 (p < 0.01). CONCLUSIONS There is a correlation between the right ventricular size obtained by three dimensional echocardiography and QRS duration on the surface ECG, indicating mechanoelectrical interaction. The severity of pulmonary regurgitation has a negative influence on right ventricular ejection fraction and combined systolic and diastolic global function, as assessed by myocardial performance.

Masked left ventricular restriction in elderly patients with atrial septal defects: A contraindication for closure?

The impact of an atrial septal defect in the elderly with reduced diastolic elasticity of the left ventricle is unclear. We studied the hemodynamic changes during balloon occlusion of atrial septal defects in patients over 60 years of age. In 18 patients (61–78 years old; median, 70), the left atrial pressure and the mitral valve inflow was measured during complete balloon occlusion of the defect and after deflation of the balloon. In seven patients, the left atrial pressure and the E/A ratio of the mitral valve inflow increased markedly (P = 0.02). Mean atrial pressures reached values of 27 mm Hg and the v‐wave peak values of 55 mm Hg. Two patients received a transcatheter device closure and developed congestive heart failure. In the elderly, an atrial septal defect can have a decompressive impact on the left ventricle. Therefore, caution appears to be warranted if atrial septal closure is planned. Cathet Cardiovasc Intervent 2001;52:177–180.

Relationship of Immunosuppression to Epstein–Barr Viral Load and Lymphoproliferative Disease in Pediatric Heart Transplant Patients

BACKGROUND Post-transplant lymphoproliferative disease (PTLD) is a severe complication in transplant recipients. Detection of increased Epstein-Barr viral (EBV) load in the peripheral blood acts as a surrogate marker for increased risk of PTLD development. We prospectively monitored EBV load, immunosuppression and PTLD in pediatric heart transplant (HTx) patients to determine risk factors for an increased EBV load and risk of PTLD. METHODS Forty-one pediatric heart transplant recipients were included and underwent prospective monitoring of their immunosuppression and ethylene-diamine tetraacetic acid (EDTA) blood sampling for EBV load (copies/microg DNA) measurement using quantitative real-time polymerase chain reaction (PCR; TaqMan) during January 2001 to December 2006. RESULTS EBV load was measurable in 70% and was significantly increased (>2,000 copies/microg DNA) in 35% of the patients, with a median EBV load of 5,100 (range 0 to 50,665 copies/microg DNA). Increased EBV load was detected in patients receiving CsA-azathioprine or more than two doses of anti-thymocyte globulin (ATG) and in those <10 years of age, without any significant differences in CsA blood levels. Lowest or negative EBV load was measured in patients receiving CsA-mycophenolate mofetil (MMF) or CsA only. CsA blood levels were not predictable for increased EBV load or PTLD. Six patients developed a EBV-associated B-cell lymphoma (PTLD), among whom 4 (67%) were receiving CsA-azathioprine. CONCLUSIONS Frequent EBV load monitoring identifies patients at high risk for PTLD development. Azathioprine and ATG are major risk factors for increased EBV load and PTLD and patients may benefit from a change of immunosuppression in addition to pre-emptive anti-viral or anti-tumor strategies.

Transcatheter Closure of Atrial Septal Defects Without Fluoroscopy Feasibility of a New Method

BACKGROUND In an effort to reduce x-ray exposure, we developed a technique for transcatheter closure of atrial septal defects under echocardiographic guidance without fluoroscopy. To assess the efficiency of this procedure for routine use, we compared our initial results with those for the conventional procedure. METHODS AND RESULTS Twenty-two randomly selected patients (median age 18 years; range 2 to 66 years) with atrial septal defects (n=13) or patent foramen ovale (n=9) underwent cardiac catheterization for possible interventional defect closure with echocardiography as the only imaging tool. Median stretched diameter was 9 mm (range 6 to 26 mm); median left-to-right shunt over the atrial septal defects was Qp/Qs=1.8 (range 1.5 to 2.6). An Amplatzer septal occluder was successfully implanted in 19 defects without fluoroscopy and in 3 with the help of radiography. After 1 month, complete defect closure was documented in all patients. Compared with the conventional procedure of a control group of 131 patients, procedure times were not significantly different (88 versus 100 minutes; P=0.09). However, the study group received significantly higher doses of propofol for sedation (9.9 versus 5.6 mg/kg body weight; P=0.002) owing to extended transesophageal echocardiography. CONCLUSIONS In the majority of patients in whom transcatheter closure of interatrial communications with the Amplatzer septal occluder is possible, the procedure can be safely performed under echocardiographic guidance without fluoroscopy.

Left ventricular conditioning in the elderly patient to prevent congestive heart failure after transcatheter closure of atrial septal defect

Transcatheter closure of atrial septal defects (ASDs) is a safe and effective treatment. Over the past years, an increasing number of elderly patients (age > 60 years) have been admitted for transcatheter closure to prevent ongoing congestive heart failure from volume overload. However, recent data point to the risk of serious acute left ventricular dysfunction leading to pulmonary edema immediately after surgical or transcatheter ASD closure in some patients. In this study, we used a technique described before to recognize in advance patients at risk of left heart failure after ASD closure. Those patients at risk were then treated with preventive conditioning medication for 48–72 hr before definitive transcatheter ASD closure was performed. Fifty‐nine patients aged over 60 years (range, 60–81.8 years; median, 68 years) were admitted to our institution for transcatheter closure of an atrial septal defect. All patients received evaluation of atrial pressures before and during temporary balloon occlusion of the ASD. Patients with left ventricular restriction due to increased mean atrial pressures (> 10 mm Hg) during ASD occlusion received anticongestive conditioning medication with i.v. dopamine, milrinone, and furosemide for 48–72 hr before definitive ASD closure with an Amplatzer septal occluder was performed. In 44 patients without any signs of left ventricular restriction, ASD closure was performed within the first session. Fifteen (25%) out of 59 patients showed left ventricular restriction. In the majority of patients with LV restriction, the mean left atrial pressures with occluded ASD were significantly decreased after 48–72 hr of conditioning medication. Definitive ASD closure was then performed in a second session. Only two patients received a fenestrated 32 mm Amplatzer occluder due to persistent increased atrial pressures > 10 mm Hg even after conditioning medication. There were no significant differences in shunt, device size, or defect size between the two groups. Balloon occlusion of atrial septal defects identifies patients with left ventricular restrictive physiology before ASD closure. Intravenous anticongestive conditioning medication seems to be highly effective in preventing congestive heart failure after interventional closure of an ASD in the elderly patient with a restrictive left ventricle. Catheter Cardiovasc Interv 2005;64:333–337.

Magnetic resonance imaging-guided balloon angioplasty of coarctation of the aorta: a pilot study

Background— MRI guidance of percutaneous transluminal balloon angioplasty (PTA) of aortic coarctation (CoA) would be desirable for continuous visualization of anatomy and to eliminate x-ray exposure. The aim of this study was (1) to determine the suitability of MRI-controlled PTA using the iron oxide–based contrast medium Resovist (ferucarbotran) for catheter visualization and (2) to subsequently apply this technique in a pilot study with patients with CoA. Methods and Results— The MRI contrast-to-noise ratio and artifact behavior of Resovist-treated balloon catheters was optimized in in vitro and animal experiments (pigs). In 5 patients, anatomy of the CoA was evaluated before and after intervention with high-resolution respiratory-navigated 3D MRI and multiphase cine MRI. Position monitoring of Resovist-treated catheters was realized with interactive real-time MRI. Aortic pressures were continuously recorded. Conventional catheterization was performed before and after MRI to confirm interventional success. During MRI, catheters filled with 25 &mgr;mol of iron particles per milliliter of Resovist produced good signal contrast between catheters and their background anatomy but no image distortion due to susceptibility artifacts. All MRI procedures were performed successfully in the patient study. There was excellent agreement between the diameters of CoA and pressure gradients as measured during MRI and conventional catheterization. In 4 patients, PTA resulted in substantial widening of the CoA and a decrease in pressure gradients. In 1 patient, PTA was ineffective. Conclusions— The MRI method described represents a potential alternative to conventional x-ray fluoroscopy for catheter-based treatment of patients with CoA.

Relation of cerebral tissue oxygenation index to central venous oxygen saturation in children

ObjectiveTo evaluate the relationship between the cerebral tissue oxygenation index measured by near-infrared spectroscopy and central venous oxygen saturation (SvO2) after corrective surgery of congenital heart defects in children.DesignProspective observational clinical study.SettingA tertiary neonatal and paediatric intensive care unit for paediatric cardiology.PatientsNeonates and children consecutively admitted to the paediatric cardiology intensive care unit after corrective surgery of non-cyanotic congenital heart defects.Measurements and resultsForty-three children were studied. Cerebral tissue oxygenation index, measured non-invasively by near-infrared spectroscopy, was compared to SvO2, measured by a catheter placed in the right atrium, and to haemodynamic and respiratory parameters. Pearson’s correlation coefficients and p values were calculated. Simultaneously measured values for SvO2 (62.2±9.8%, 39.8–80.4%) and cerebral tissue oxygenation index (56.7±8.8%, 35.8–71.2%) showed a significant correlation (r=0.52, p<0.001).ConclusionCerebral tissue oxygenation index and SvO2 are not interchangeable parameters, but cerebral tissue oxygenation index reflects the haemodynamic influence on cerebral oxygenation after cardiovascular surgery. Further work is necessary to confirm the clinical role of continuous non-invasive measurement of cerebral tissue oxygenation index with regard to the variations of global systemic oxygen consumption after cardiac surgery in children.

Neuron-specific enolase is unaltered whereas S100B is elevated in serum of patients with schizophrenia — Original research and meta-analysis

Previous studies reported altered levels of the astrocytic marker S100B in schizophrenia. To clarify mechanisms, we measured weekly serum levels of S100B together with the neuronal marker neuron-specific enolase in 20 patients with schizophrenia and 19 age- and gender-matched control subjects. S100B was elevated at admission and discharge in schizophrenic patients compared with control subjects, whereas there were no significant differences for neuron-specific enolase. Treatment had no impact on either S100B or neuron-specific enolase. A systematic, quantitative meta-analysis of all published studies involving 380 patients and 358 control subjects revealed elevated serum S100B in schizophrenia without any effect of antipsychotic treatment. Results suggest that increases of serum S100B are related to active secretion of S100B by astrocytes in combination with blood-brain barrier dysfunction in schizophrenia.

Bicuspidization of the Unicuspid Aortic Valve: A New Reconstructive Approach

BACKGROUND Unicuspid anatomy of the aortic valve is infrequent but may require intervention by age 40 for severe regurgitation. We propose a new repair technique for the regurgitant unicuspid valve by converting it into a bicuspid aortic valve. METHODS Between November 2003 and September 2007, 20 patients underwent regurgitant unicuspid aortic valve repair: 13 had aortic regurgitation (AR) and 7 had combined regurgitation and stenosis. Four patients had previously undergone balloon valvuloplasty for critical aortic stenosis. The aim of the repair was to construct a bicuspid valve with two normal commissures and unrestricted cusp motion. The fused cusp tissue was divided anteriorly and a new commissure of normal height was created. Noncoronary and right coronary cusps were extended with autologous pericardium. Concomitant operations included ascending aortic replacement in 7 and resection of subaortic stenosis in 1. RESULTS No early or late deaths occurred. Intraoperative echocardiography revealed minimal or no AR in 19 patients. Follow-up was 4 to 47 months. One patient underwent valve re-repair for recurrent and progressive aortic regurgitation 3 years postoperatively. All other valves remained stable throughout the follow-up period. Freedom from relevant aortic insufficiency (> or = II) at 4 years was 77%; freedom from reoperation was 67%; and freedom from valve replacement was 100%. CONCLUSIONS The regurgitant unicuspid aortic valve can be repaired successfully and reproducibly by converting it into bicuspid anatomy. The functional results are comparable with those obtained in reconstructed bicuspid aortic valves. With this approach, replacement can be avoided in most patients with regurgitant unicuspid aortic valves.

Diagnosis and treatment of post-transplantation lymphoproliferative disorder in pediatric heart transplant patients.

Abstract:  PTLD is a severe complication in transplant recipients. Detection of increased EBV load in the peripheral blood acts as a surrogate marker for increased risk of PTLD development. We analyzed the time course of the disease, its severitiy, the organs involved, and mortality rates in our institutional experience of pediatric heart transplantation. This paper identifies risk factors for PTLD and describes the different ways of diagnosing and treating the disease. PTLD was screened for in 146 pediatric heart transplant patients using a retrospective analysis in patients who received transplantation before 1998. Prospective determination was performed in 72/146 patients transplanted after 1998 within the post‐transplant follow‐up. The occurrence of PTLD with all interventions, including tapering of immunosuppression, surgery, viral monitoring, and antiviral interventions, was recorded. PTLD was diagnosed in 12/147 (8.2%) children at a mean age of 7.2 ± 3.3 yr after a mean post‐transplant period of 3.2 ± 2.2 yr. PTLD manifested in: lymph nodes (n = 4), intestine (n = 3), tonsils and adenoids (n = 2), eye (n = 2), and lung (n = 1). It was diagnosed in 7/12 as a monomorphic B‐cell lymphoma and in four patients as a monomorphic Burkitt lymphoma, a polymorphic B‐cell lymphoma, a T‐cell rich or angiocentric lymphoma (Liebow) and as reactive plasmacytic hyperplasia (early lesion), respectively. Histology was not possible in one patient with ocular manifestation. EBV association was 83%. Risk factors in the comparison with patients without PTLD were age at time of Tx, primary EBV infection after Tx, use of Azathioprine and ≥3 doses of ATG. CMV mismatch and CMV infection, rejection episodes and steroids were not risk factors. Despite reduction of immunosuppression, treatment consisted of surgical procedures to remove tumor masses (n = 6), Rituximab (n = 5), polychemotherapy (n = 3), antiviral (n = 1) and autologous T‐cell therapy (n = 1). All patients demonstrated full remission without death related to PTLD or treatment at 3.9 (1.3–6.2) yr median follow‐up time. The manifestation of PTLD in pediatric heart transplant recipients is associated with EBV infection and is predominantly in the form of a B‐cell lymphoma. A tight and specific follow‐up including early assessment of immunity status and specific therapeutic intervention to improve cellular immunity is warranted and may contribute to a significant reduction of PTLD‐related morbidity and mortality.