46 research outputs found
Successful Repair of Infant with Anomalous Origin of the Left Coronary Artery from the Pulmonary Artery Presenting with Heart Failure, Dilated Cardiomyopathy and Mitral Regurgitation
Anomalous origin of the left coronary artery from the pulmonary artery is a rare congenital heart anomaly that account for up to 0.5% of all congenital heart disease. Usually, infants' patients may present with failure to thrive, feeding difficulties, sweating, irritability or sudden cardiac death. However, they may be asymptomatic. This syndrome has a high mortality rate if left untreated during infancy period. Echocardiography and electrocardiography are helpful in detecting and establishing the diagnosis of Anomalous origin of the left coronary artery from the pulmonary artery for infants. Surgical repair to restore normal anatomical position of coronary system is the definitive intervention. Early detection and surgical intervention has significant positive impact on survival rate. This paper presents a case of a four months old girl, who presented with heart failure, dilated cardiomyopathy and mitral regurgitation and thereafter was diagnosed with Anomalous origin of the left coronary artery from the pulmonary artery syndrome. Keywords: Anomalous origin of the left coronary artery from the pulmonary artery- Transthoracic echocardiography -Left anterior descending artery- Surgical repair
In Vitro NMR Study of Magnetization Exchange at Low Field and Proteoglycan-Depletion at High Field in Articular Cartilage
Magnetization exchange between different spin reservoirs, or spin groups, in cartilage tissue is an important aspect of the use of Magnetic Resonance Imaging (MRI) in the early detection of osteoarthritis (OA). A low field (Larmor frequency of 30 MHz) NMR study of relaxation times in bovine articular cartilage was undertaken with the aim of elucidating details about magnetization exchange in this tissue.
A key element of successful multi-site exchange modeling is the availability of a sufficient number of apparent relaxation parameters to model the intrinsic multi- site exchange scenario. Two-Dimensional (2D) time domain NMR spin-lattice relaxation experiments in the laboratory frame (T1 experiments) and the rotating frame (T1ρ experiments) were performed in articular cartilage, which allows for effective extraction of relaxation parameters from the composite NMR response from the heterogeneous cartilage tissue. 2D inversion recovery T1 experiments using non-selective excitation and monitor pulses as well as selective excitation and non-selective monitor pulses were used.
The 2D relaxation results for each of the above experiments were then analysed for exchange by comparing the experimentally observed parameters to the apparent parameters, calculated from a set of intrinsic parameters, which were adjusted until a reasonable match was realized. In this multi-experiment approach the exchange results from one experiment can be used to corroborate the exchange results from another experiment.
In order to circumvent the considerable masking effect that the bulk water has on effective proton NMR characterization of cartilage macromolecular components, the above 2D relaxation-exchange analysis approach also was applied to bovine cartilage tissue in which H2O was replaced with D2O, as well as cartilage tissue in which the bulk water was frozen, so as to allow for the selective saturation of the ice proton magnetization. Combining relaxation times and magnetization exchange analyses results from the four cases, natural cartilage at 3oC and -10oC as well as deuterated cartilage at 3oC and -10oC, a 4-site exchange scenario involving water, proteoglycan (PG) and two collagen spin reservoirs, was arrived at for cartilage tissue. Approximate rates for magnetization exchange between macromolecule spins and water spins as well as for inter-macromolecule magnetization exchange are presented.
In addition, the present results have clearly demonstrated that at -10oC, at which temperature the bulk water in the tissue is frozen, the collagen proton magnetization in the tissue exhibit a similar relaxation behavior as seen at 3oC; i.e., the collagen proton magnetizations do not appear to be appreciably affected by the freezing phase transition.
Loss of PG is an important indicator of early OA. An ideal MRI scheme for OA detection can be envisioned to involve the direct detection of the degradation of PG with progression of the disease, while at the same time monitoring the collagen content, which is not significantly affected by early OA and can be used as internal reference. In this part of the thesis, first, high field (Larmor frequency of 500 MHz) Magic Angle Spinning (MAS) NMR was used to monitor the changes in the PG spectra of the articular cartilage with dehydration, and with PG-degradation (using trypsin). Second, articular cartilage samples were modified enzymatically to achieve different PG-depletion levels using the trypsin enzyme and then chemical shift imaging (CSI) was used to obtain the PG spectra and a static spectral experiment was performed to measure the broad collagen spectra. The ratio of the PG spectral area to that of the collagen spectral area defines PG content relative to collagen content. As the collagen content does not change appreciably for early OA, this approach provides a relative PG content, which is expected to be useful for in vivo OA detection
Successful Heart-Lung Transplantation in Saudi Arabia: A Case Report
Heart-lung transplantation is a rare surgical option performed to replace both the heart and lungs in a single operation when other treatment options have failed. Here, we present a case report of heart-lung transplant operation performed on a 17- year- old male with complex congenital heart disease, pulmonary hypertension and heart failure with ejection fraction <25%. We also outline the operative indications, contraindications, prognosis, care of the patient and complications of heart-lung transplantation. Keywords: Heart-lung transplantation; Indications ; Contraindications
Ruptured duodenal varices arising from the main portal vein successfully treated with endoscopic injection sclerotherapy: a case report
Duodenal varices result from retroperitoneal portosystemic shunts that usually come from the pancreaticoduodenal vein and drain into the inferior vena cava. Because they are a rare but fatal cause of gastrointestinal bleeding, a prompt hemostatic intervention is mandatory. A 62-year-old man who had a history of excessive alcohol consumption presented with massive hematemesis and melena. Emergent endoscopy revealed ruptured varices with an adhering whitish fibrin clot on the postbulbar portion of the duodenum. Abdominal computed tomography demonstrated a cirrhotic liver with venous collaterals around the duodenum and extravasated contrast in the second and third portions. The collaterals originated from the main portal vein and drained via the right renal vein into the inferior vena cava. Endoscopic injection sclerotherapy with cyanoacrylate was successful in achieving hemostasis, and resulted in the near eradication of duodenal varices at a 6-month follow-up
Extracorporeal life support in mitral papillary muscle rupture: Outcome of multicenter study
Background: Post-acute myocardial infarction papillary muscle rupture (post-AMI PMR) may present variable clinical scenarios and degree of emergency due to result of cardiogenic shock. Veno-arterial extracorporeal life support (V-A ECLS) has been proposed to improve extremely poor pre- or postoperative conditions. Information in this respect is scarce.Methods: From the CAUTION (meChanical complicAtion of acUte myocardial infarcTion: an InternatiOnal multiceNter cohort study) database (16 different Centers, data from 2001 to 2018), we extracted adult patients who were surgically treated for post-AMI PMR and underwent pre- or/and postoperative V-A ECLS support. The end-points of this study were in-hospital survival and ECLS complications.Results: From a total of 214 post-AMI PMR patients submitted to surgery, V-A ECLS was instituted in 23 (11%) patients. The median age was 61.7 years (range 46-81 years). Preoperatively, ECLS was commenced in 10 patients (43.5%), whereas intra/postoperative in the remaining 13. The most common V-A ECLS indication was post-cardiotomy shock, followed by preoperative cardiogenic shock and cardiac arrest. The median duration of V-A ECLS was 4 days. V-A ECLS complications occurred in more than half of the patients. Overall, in-hospital mortality was 39.2% (9/23), compared to 22% (42/219) for the non-ECLS group.Conclusions: In post-AMI PMR patients, V-A ECLS was used in almost 10% of the patients either to promote bridge to surgery or as postoperative support. Further investigations are required to better evaluate a potential for increased use and its effects of V-A ECLS in such a context based on the still high perioperative mortality
Ex-Vivo Characterization of Minced Pulp Tissue Explants
Regenerative endodontics techniques have recently become one of the most investigated areas in the field of endodontics. Utilizing tissue engineering concepts enable us to restore teeth vitality and health after the pulp tissue damage. Dental pulp stem cells (DPSC) transplantation faced several step-backs due to cell culture requirement and regulatory hurdles for in vitro expansion of cells. Our group demonstrated previously dental pulp tissue explants generate mesenchymal stem cells, named MP-MSCs, that exhibited stem cell properties such as differentiation capacities and mineralization potential in vitro which was comparable to DPSCs. We established the fundamental rational for the usage of pulp tissue grafting in the field of tissue engineering and regenerative endodontics. In this study, we aimed to characterize the dental pulp tissue explants and MP-MSCs in vitro through serial tissue passages, comparing their odontogenic differentiation potential. This study demonstrated that cells migrating out from dental pulp tissue explants at later passages retained their growth potential as well as odontogenic differentiation capacity. Minced-pulp MSCs also expressed stem cells marker, CD146, at late tissue passage (T10). This study indicates that dental pulp tissue explants can potentially yield unlimited source of mesenchymal stem cells which builds up on our novel approach of utilizing direct pulp tissue grafting as a regenerative endodontic therapy
Photoneutrons and Gamma Capture Dose Rates at the Maze Entrance of Varian TrueBeam and Elekta Versa HD Medical Linear Accelerators
Herein, we evaluated the neutron and gamma capture dose equivalent rates at the maze entrance of Varian TrueBeam and Elekta Versa HD™ medical linear accelerators (linacs) using experimental measurements as well as empirical calculations. Dose rates were measured using calibrated neutron and gamma area survey meters placed side-by-side at the measurement point of interest. Measurements were performed at a source-to-detector distance of 100 cm, with a 10 × 10 cm2 field size therapeutic X-ray beam, and a 30 × 30 × 15 cm3 solid water patient equivalent phantom, with a linac operating at 15, 10 MV, and 10 MV flattened filter-free (FFF). Dose rates were also measured at different points at the centerline along the maze towards the maze entrance. The measured dose equivalent rates at the maze entrance were comparable to those reported in the literature. The dose rates along the maze decreased exponentially towards the maze entrance and were significant for short maze lengths. The evaluated empirical methods for estimating neutron dose rates at the maze entrance of a linac proposed by Kersey, the modified Kersey method and Falcão method, agree by a factor of two from the experimental measurements. The results revealed vital radiation protection considerations owing to neutron contamination in external beam therapy