The Experts below are selected from a list of 237 Experts worldwide ranked by ideXlab platform

Ramarathnam Krishnakumar - One of the best experts on this subject based on the ideXlab platform.

  • In-vitro Validation of Image Guided Surgery System with 3D Pre-Operative Visualization for Atrial Transseptal Puncture
    2014 18th International Conference on Information Visualisation, 2014
    Co-Authors: Mahadevu Jeevan, Rathinasamy Jebaraj, Ramarathnam Krishnakumar
    Abstract:

    The left atrium (LA) is the most difficult cardiac chamber to access percutaneously. The route through the Systemic Venous System across the interatrial septum is mostly preferred to the more retrograde arterial route as larger catheters and devices could be manipulated safely. The transseptal (TS) puncture permits this direct route to the LA through the interatrial septum which is necessary in patients with a trial fibrillation (cardiac ablation), patent fossa ovalis (PFO), a trial septal defect (ASD) repair, left atrium appendage closure, balloon mitral valvuoloplasty, pulmonary vein stenos is intervention, Ante grade ventricular septal defect closure, stent implantation in the right internal carotid artery. For a safe TS puncture, one requires a delivery System and medical imaging software. At present doctors use biplanar fluoroscopic images during navigation and TS puncture. The two-dimensional echocardiography aids the doctor during the TS puncture. A complete three-dimensional visualization is yet to be established. We propose an efficient method for target localization pre-operatively and three-dimensional visualization with respect to catheter tip of the scene during the procedure. This technique eliminates fluoroscopy. The technique proposed in this work has been validated in-vitro using an a trial phantom, used to train doctors in electrophysiology (EP) labs. The pre-operative image obtained using MRI is registered with the phantom and the catheter tip location inside the phantom and is visualized in three-dimensions.

Glen B Drake - One of the best experts on this subject based on the ideXlab platform.

  • persistent left superior vena cava incidence significance and clinical correlates
    International Journal of Cardiology, 2002
    Co-Authors: Eron Crouch, Glen B Drake
    Abstract:

    Persistent left superior vena cava (PLSVC) is a remainder of the physical examination was unremarkcommon anomaly of the Systemic Venous System [1]. able. Multiple ECGs revealed sinus rhythm, with a It results from persistent patency of the left anterior marked first-degree atrioventricular block and left cardinal vein that drains into a dilated coronary sinus. bundle branch block with a heart rate ranging from Its incidence is reported between 0.3 and 0.5% in the 38 to 78 beats per min. Blood chemistries were general population [2]. Approximately 50–70% of within normal limits. She underwent TEE to rule out these patients are at risk of paradoxical embolism an intracardiac source of embolism and atrial septal because of accompanying lesions (atrial septal defect, defect and to define her cardiac anatomy. This unroofed coronary sinus, or direct communication of showed no evidence of cardiac masses, but did the vein to the left atrium). demonstrate a PLSVC draining into the right atrium This case report illustrates the diagnostic role of via a dilated coronary sinus (Fig. 1). Saline contrast echocardiography in the evaluation and diagnosis of injection was negative for intracardiac shunt. There this relatively rare congenital anomaly. was bi-atrial and bi-ventricular enlargement. The A 60-year-old white woman with a recent history estimated left ventricular ejection fraction was 0.45. of dizziness was referred for evaluation. She had a No segmental wall motion abnormalities were noted. history of paroxysmal atrial fibrillation, left ventricuDuring early embryological development, Venous lar dysfunction, and a history of a congenital heart return from the head and arms normally drains to the disease with an atrial septal defect repair. Her vital right atrium via the left and right anterior cardinal signs were stable. Cardiac examination revealed a veins. At approximately 8 weeks gestation, the left grade 2/6 holosystolic murmur at the apex radiating brachiocephalic vein develops as a bridge between to the left axilla. There were no gallops or rubs. The the left and right anterior cardinal veins. The portion splitting of the second heart sound was normal. The of the left anterior cardinal vein caudal to the bridging left brachiocephalic vein normally collapses, then degenerates leaving only the right anterior *Corresponding author. Present address: Division of Cardiology, cardinal vein which becomes the superior vena cava. Marshfield Clinic, 1000 Oak Street, WI 54449, USA. Tel.: 11-715-387If the caudal portion of the left anterior cardinal vein 5301; fax: 11-715-389-4555. E-mail address: takt@mfldclin.edu (T. Tak). remains patent, it becomes a PLSVC which drains

Alain Carpentier - One of the best experts on this subject based on the ideXlab platform.

  • model of complete separation of the hepatic veins from the Systemic Venous System
    The Annals of Thoracic Surgery, 2000
    Co-Authors: Christian P Brizard, Nathalie Goussef, Juan C Chachques, Alain Carpentier
    Abstract:

    Abstract Background . In patients undergoing a Fontan operation, partial diversion of the hepatic veins to the pulmonary Venous atrium has been tried with various techniques. They failed because of the development of intrahepatic collaterals leading to an unacceptable right-to-left shunting. We postulate that to avoid the formation of intrahepatic collaterals, the totality of the liver has to be drained into the same pressure compartment. We have designed a model of cavopulmonary anastomosis in which a prosthetic conduit reproduces an azygos continuation, associated with the diversion of the totality of the hepatic Venous return. This article reports on the early hemodynamics and the fate of the separation of the two Venous compartments in long-term survivors. Methods . Eighteen goats were operated on; the pulmonary artery and hepatic vein pressures were recorded. During month 2, an opacification of the inferior vena cava and the cavopulmonary connection was performed. Between months 6 and 14, another opacification was performed, together with pressure recording at both ends of the conduit. Results . Postoperatively the pulmonary artery pressure was pulsatile with a mean of 10 mm Hg and the hepatic vein pressure was 0 mm Hg. The first angiogram showed patent tubes with fast progression of the contrast. Throughout the inferior vena cava injection, there was no opacification of the portal or hepatic veins. The late study showed a narrowed conduit in all animals. During the injection, a collateral was injected, feeding into the inferior mesenteric vein. No collateral circulation could be seen draining directly into the liver. The median gradient between the two ends of the conduit was 11 mm Hg. Conclusions . The isolation of the entire hepatic Venous drainage is feasible and efficient for the separation of two pressure compartments. No intrahepatic collaterals are observed with this model at short- or long-term follow-up. The separation of the hepatic Venous drainage should persist without collateral circulation as long as the inferior vena cava pressure stays at the levels observed in Fontan circulation.

Mahadevu Jeevan - One of the best experts on this subject based on the ideXlab platform.

  • In-vitro Validation of Image Guided Surgery System with 3D Pre-Operative Visualization for Atrial Transseptal Puncture
    2014 18th International Conference on Information Visualisation, 2014
    Co-Authors: Mahadevu Jeevan, Rathinasamy Jebaraj, Ramarathnam Krishnakumar
    Abstract:

    The left atrium (LA) is the most difficult cardiac chamber to access percutaneously. The route through the Systemic Venous System across the interatrial septum is mostly preferred to the more retrograde arterial route as larger catheters and devices could be manipulated safely. The transseptal (TS) puncture permits this direct route to the LA through the interatrial septum which is necessary in patients with a trial fibrillation (cardiac ablation), patent fossa ovalis (PFO), a trial septal defect (ASD) repair, left atrium appendage closure, balloon mitral valvuoloplasty, pulmonary vein stenos is intervention, Ante grade ventricular septal defect closure, stent implantation in the right internal carotid artery. For a safe TS puncture, one requires a delivery System and medical imaging software. At present doctors use biplanar fluoroscopic images during navigation and TS puncture. The two-dimensional echocardiography aids the doctor during the TS puncture. A complete three-dimensional visualization is yet to be established. We propose an efficient method for target localization pre-operatively and three-dimensional visualization with respect to catheter tip of the scene during the procedure. This technique eliminates fluoroscopy. The technique proposed in this work has been validated in-vitro using an a trial phantom, used to train doctors in electrophysiology (EP) labs. The pre-operative image obtained using MRI is registered with the phantom and the catheter tip location inside the phantom and is visualized in three-dimensions.

Eron Crouch - One of the best experts on this subject based on the ideXlab platform.

  • persistent left superior vena cava incidence significance and clinical correlates
    International Journal of Cardiology, 2002
    Co-Authors: Eron Crouch, Glen B Drake
    Abstract:

    Persistent left superior vena cava (PLSVC) is a remainder of the physical examination was unremarkcommon anomaly of the Systemic Venous System [1]. able. Multiple ECGs revealed sinus rhythm, with a It results from persistent patency of the left anterior marked first-degree atrioventricular block and left cardinal vein that drains into a dilated coronary sinus. bundle branch block with a heart rate ranging from Its incidence is reported between 0.3 and 0.5% in the 38 to 78 beats per min. Blood chemistries were general population [2]. Approximately 50–70% of within normal limits. She underwent TEE to rule out these patients are at risk of paradoxical embolism an intracardiac source of embolism and atrial septal because of accompanying lesions (atrial septal defect, defect and to define her cardiac anatomy. This unroofed coronary sinus, or direct communication of showed no evidence of cardiac masses, but did the vein to the left atrium). demonstrate a PLSVC draining into the right atrium This case report illustrates the diagnostic role of via a dilated coronary sinus (Fig. 1). Saline contrast echocardiography in the evaluation and diagnosis of injection was negative for intracardiac shunt. There this relatively rare congenital anomaly. was bi-atrial and bi-ventricular enlargement. The A 60-year-old white woman with a recent history estimated left ventricular ejection fraction was 0.45. of dizziness was referred for evaluation. She had a No segmental wall motion abnormalities were noted. history of paroxysmal atrial fibrillation, left ventricuDuring early embryological development, Venous lar dysfunction, and a history of a congenital heart return from the head and arms normally drains to the disease with an atrial septal defect repair. Her vital right atrium via the left and right anterior cardinal signs were stable. Cardiac examination revealed a veins. At approximately 8 weeks gestation, the left grade 2/6 holosystolic murmur at the apex radiating brachiocephalic vein develops as a bridge between to the left axilla. There were no gallops or rubs. The the left and right anterior cardinal veins. The portion splitting of the second heart sound was normal. The of the left anterior cardinal vein caudal to the bridging left brachiocephalic vein normally collapses, then degenerates leaving only the right anterior *Corresponding author. Present address: Division of Cardiology, cardinal vein which becomes the superior vena cava. Marshfield Clinic, 1000 Oak Street, WI 54449, USA. Tel.: 11-715-387If the caudal portion of the left anterior cardinal vein 5301; fax: 11-715-389-4555. E-mail address: takt@mfldclin.edu (T. Tak). remains patent, it becomes a PLSVC which drains