Pains in the chest, back, or arms can be the first indication of a heart attack. If this suspicion is confirmed by a blood test and an ECG that are typical of a heart attack, defined emergency procedures are implemented, up to and including surgery. However, if the examination does not reveal a clear diagnosis, a catheter examination is often used in the next step. At the ESC (European Congress of Cardiology, September 3-6, 2005 in Stockholm, Sweden), Siemens Medical Solutions will be showing how to simplify and accelerate the workflow of cardiological emergency diagnostics through cross-modality cooperation. In this case, the Somatom Sensation Cardiac 64 computed tomography system (CT), Axiom Artis dBC digital radiography system, and the Axiom Sensis recording system are used.
In patients with equivocal diagnosis, the CT system provides crystal-clear images of the heart within seconds, enabling safe and sure diagnosis of cardiac infarction, vascular occlusion, or other coronary diseases. A catheter is subsequently applied only if vascular dilation or the use of a stent is required. This intervention is performed using the Axiom radiography system which supports the physician through its latest cardiology software programs such as Interventional Cardiac 3D (IC3D) for stent planning.
Coronary heart disease (CHD) is the leading cause of death in Western industrialized nations. If detected early, it can be treated safely and quickly. If it progresses, for example by occluding a vessel, the result can be cardiac infarction. Difficulties such as pain in the chest or back (Angina pectoris) prior to a heart attack only occurs in approximately 50 percent of cases; in the same percentage of cases, a heart attack occurs with no prior warning. “If we are unsuccessful in reopening the occluded vessel, the cardiac muscle dies within a few hours”, according to Associate Professor Dr. Stephan Achenbach, Assistant Professor at the Medical Clinic II – Cardiology, Angiology – of the Erlangen University Hospital, Germany.
It all depends on an early, definite diagnosis: if the results of the ECG and stress tests however do not provide unequivocal confirmation of a (threatening) infarction and the need for corresponding treatment, the heart has to be examined more closely, which generally occurs using a catheter. The catheter examination is an invasive procedure where the catheter is directly inserted into the coronary vessels.
This invasive catheter procedure can be replaced by a non-invasive procedure for specific patient groups in cases of diagnosis – for example for patients with ambiguous chest pain. In this case, angiography is performed with the CT system after the blood the blood test and an ECG. The patient holds his breath less than 10 seconds while the cardiac ECG is acquired synchronously. With a rotation time of 0.33 seconds, the Somatom Sensation Cardiac 64 reaches a temporal resolution of 83 milliseconds and can therefore “freeze” heart movement so to speak. The physician can then precisely view even the smallest vessels on the monitor, and after a few minutes is able to reach a correct diagnosis. The syngo Circulation software ensures a user-friendly diagnostic workflow. It supports the physician from automatic cardiac segmentation, to segmentation of the coronary vessels and stenosis quantification (degree of occlusion of the coronary vessels), through fully automatic functional analysis and reporting.
If necessary, additional treatment is then performed in the cath lab. Today, such treatment is minimally invasive and includes, for example, opening an occluded vessel with a balloon catheter and the placement of a stent. The biplane Axiom Artis dBC C-arm for digital radiography is used for imaging during the invasive procedure. Its two flat detectors result in excellent image quality. At the same time, Axiom Sensis enables recording and performance of all hemodynamic and electrophysiological examinations from a single measuring station. Both systems are important tools, and interventional cardiology would not be the same without them.
IC3D software is used primarily for stent planning. IC3D calculates the stenosis dimensions for selecting an optimal stent. The subsequent regular checks of the position and permeability of the stent are performed using the Somatom Sensation Cardiac 64.
Siemens Medical Solutions
is one of the world’s largest suppliers to the healthcare industry. The company is known for bringing together innovative medical technologies, healthcare information systems, management consulting, and support services, to help customers achieve tangible, sustainable, clinical and financial outcomes. From imaging systems for diagnosis, to therapy equipment for treatment, to patient monitors to hearing instruments and beyond, Siemens innovations contribute to the health and well-being of people across the globe, while improving operational efficiencies and optimizing workflow in hospitals, clinics, home health agencies, and doctors' offices. Employing approximately 31,000 people worldwide and operating in more than 120 countries, Siemens Medical Solutions reported sales of 7.07 billion EUR, orders of 8.12 billion EUR and group profit of 1.05 billion EUR for fiscal 2004.
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