High image quality and outstanding operability to support advanced catheterization procedures at a leading national center.

NCVC moved to Northern Osaka Health and Biomedical Innovation Town (NohBIT), which is situated in a pleasant and easily accessible area. With its principal mission of investigating and controlling cardiovascular diseases, the center is deeply involved in medical treatment, research, and development. The number of catheterization labs has increased from six in the old hospital to nine in the new hospital in order to strengthen emergency services. Four Alphenix-series angiography systems produced by Canon Medical Systems Corporation have been installed for use in the coronary disease unit and for emergency care. We interviewed Dr. Yasuhide Asaumi (Chief Physician, CCU, Division of Coronary Diseases) and Mr. Yoshinobu Kita (Deputy Chief Technologist, Department of Radiology) to find out how the Alphenix range of solutions have improved their percutanesous coronary interventions (PCI).

The Cardiovascular Department provides high-quality advanced healthcare services to patients with cardiovascular diseases through all stages, from preventive care to acute care to chronic care. It is made up of the Division of Coronary Diseases, the Division of Vascular Diseases, the Division of Heart Failure, the Division of Pulmonary Circulation, and the Division of Arrhythmia. The staff of this department includes approximately 90 physicians. In addition, a team specializing in the emergency and intensive care of cardiac patients works in shifts to ensure 24/7 support in the coronary care unit (CCU), which provides advanced medical care, including catheter-based interventions and mechanically assisted circulation.

Following the center's relocation to a densely populated urban area, the rapid intake of emergency patients was set as one of the main goals, and the emergency room (ER), catherization labs, CCU, stroke care unit (SCU), and radiology unit were all placed close together on the ground floor. The number of catheterization labs was increased from six in the old hospital to nine in the new hospital in order to create a center that is able to respond flexibly to emergency cases.

Dr. Asaumi, Chief Physician, while describing the background of constructing the catheterization labs in the new hospital, said, "One of the main points here was to place a catheterization lab adjacent to the ER. The number of labs was increased because minimally invasive catheter interventions have been more actively employed in the treatment of patients with coronary artery disease and cerebral ischemia. In the future, we expect that small and medium-size hospitals will find it difficult to support catheter-based treatment, and cases will tend to come to our center. Also, from the viewpoint of optimizing our workflow, we felt that having more labs would allow us to minimize the number of procedures performed outside normal working hours."

The center performs approximately 650 PCI procedures a year. Patients with ischemic heart disease receive treatment in the Division of Coronary Diseases if they have stable coronary artery disease and in the CCU if they have acute coronary syndrome. However, in both acute and chronic cases, PCI is performed by a team consisting of cardiologists and interventionalists. Two angiography systems (one Alphenix and one from another manufacturer) are used, with the Alphenix system employed more frequently for emergency PCI procedures performed by the interventionalists on call.

Dr. Asaumi, Chief Physician, said that he has great confidence in the ease of operation and image quality of Canon Medical's angiography systems based on his experience at the old hospital. Regarding Alphenix, he stated, "The performance of the system is as reliable as I had expected. I can operate it with confidence even during challenging PCI procedures."

The center has also installed three CT systems with cardiac CT capabilities, including a 320-row Dynamic Volume CT Aquilion ONE system produced by Canon Medical Systems Corporation. Dr. Asaumi observed, "Coronary CT allows us to obtain detailed information concerning atherosclerosis in a short time, and we are now treating more patients by performing PCI immediately after coronary CT, without the need for coronary angiography." He also noted, "By proactively performing coronary CT in low-risk patients with suspected coronary artery disease, we do not miss patients who require PCI and are able to implement PCI more appropriately." Close collaboration between the Division of Coronary Diseases and the CCU and between radiologists and radiological technologists permits the various modalities to be employed more effectively and appropriately in emergency cases.

With regard to image quality, the innovative imaging chain has been designed to acquire higher quality images to support more precise and complex catheter operations. The dynamic range of the FPD has been increased by a factor of 16, resulting in outstanding image quality with minimal halation, flare, and image loss. Dr. Asaumi is very impressed with the image quality, stating, "Alphenix provides images with very clear contrast and high visibillity. There have recently been significant advances in interventional devices as well as improvements in the precision, of guidewire control. Therefore, we now require a high level of image quality that allows us to observe delicate movements, such as monitoring the direction of a wire tip that responds precisely to delicate manipulation by the interventionalist. Compared with other systems, I feel that Alphenix helps us to more clearly see the movements of the wire when we treat calcified or complex lesions."

The improvement in image quality also increases the work efficiency of the allied healthcare professionals who support the interventionalists. Mr. Kita, Deputy Chief Technologist, noted, "Because halation is unlikely to occur during fluoroscopy, we do not need to focus so much of our attention on the compensation filter, allowing us to perform other tasks such as repositioning the monitor."

Furthermore, Alphenix is designed with a stent enhancement functions that are very helpful in PCI: Alphenix New Stent Mode. Describing their effectiveness, Dr. Asaumi said, "After the stent has been expanded, the balloon is inflated again to anchor the stent to the wall by pressure. Stent enhancement mode makes it easier to see the stent and clearly shows its positional relationships with the balloon, helping to ensure a successful outcome."

A one-hand grip has been adopted for operation of the C-arm and the table. Describing its excellent operability, Dr. Asaumi reported, "We can control the C-arm intuitively, and we feel that arm movements are lighter and more responsive compared to other systems. The grip allows us to perform arm control and panning with one hand, so we can adjust the angle with the other hand. This outstanding maneuverability is extremely helpful in emergency PCI."

During a procedure, the Dose Tracking System (DTS) should be displayed. This is a mapping function for monitoring the entrance skin dose in real time. With regard to its effectiveness, Dr. Asaumi explained, "DTS helps us to avoid any concentration of the dose at one location during long procedures and therefore allows us to minimize radiation exposure."

With the combined use of the Alphenix Workstation, 3D images and C-arm movement can be linked and controlled in an integrated manner. The angles can also be confirmed.
Dr. Asaumi expressed his high expectations by saying, "We would like to fully utilize PCI-assistance software in order to perform safer and smoother procedures, such as linking the display angle of preoperative 3D CT merging and fluorography images."

The National Cerebral and Cardiovascular Center and Canon Medical Systems Corporation have forged a comprehensive agreement to promote industry-academia collaboration. The newly established OIC will serve as a base for open innovation with companies, and there are high expectations that this joint research in close collaboration with a domestic company will lead to the development of new technologies created in Japan.

Dr. Asaumi described the future prospects of the system by stating, "Alphenix is a system with great potential. As an angiography system, the hardware has already achieved a high level of development, and further software development will become more important in the future. We believe that developing new software that contributes to better diagnosis and treatment is one of our primary missions, and we plan to focus our efforts in this area." The clinical applications and research studies involving the Alphenix series at this national center, shall bring further greater attention in the cutting edge prevention and treatment of cardiovascular diseases. //


This article was originally published in INNERVISION (35·3) 2020.