BBI Contributing Writer

SAN DIEGO, California – One of the main educational offerings of the annual meeting of the American Society of Echocardiography (ASE; Raleigh, North Carolina), held here in June, was a campaign to inform women that heart disease and stroke will kill almost 50% of all women in the U.S. "It's not just a man's disease," said the society. Echocardiograms are considered as extremely helpful in the diagnosis of cardiovascular disease in all its forms.

New information presented at the ASE meeting noted improved assessment of the heart's left atrial (LA) volume by echocardiography may be used to predict elderly patients' first ischemic stroke. Ischemic strokes, caused by blood clots blocking vessels in the brain, account for 83% of the about 700,000 incidences of stroke each year in the U.S. Every 3.3 minutes, someone dies of a stroke, making it the nation's No. 3 cause of death. Heart disease and cancer are Nos. 1 and 2.

Echocardiography provides physicians with a noninvasive method for viewing the heart and related blood vessels using ultrasound. With the information provided by echocardiography, doctors can determine the patient's risk for heart-related health problems and plan treatment to prevent or ease heart disease. In 1998, 14.6 million echocardiograms were performed. More than 9 million were performed in hospitals and about 5 million in physicians' offices. There are more than 35,000 registered sonographers in the world.

Echocardiography uses high-frequency sound waves to produce a real-time view of all the chambers of the heart, the heart valves, the heart muscle and the great blood vessels entering and leaving the heart. It shows the physician the sizes of the four chambers of the heart, the strength of the heart muscle, the presence or absence of fluid around the heart; problems with the valves of the heart, congenital heart disease, information about the pressures within the chambers of the heart, and information about erratic heartbeats.

Physicians at the Mayo Clinic (Rochester, Minnesota) retrospectively studied 1,554 Olmsted County, Minnesota, residents age 65 or over who had received an echocardiogram during the years 1990 to 1998. They found that a LA volume greater than or equal to 32ML/m2 was associated with higher risk of stroke occurrence.

"Our study provides preliminary evidence that echo may be helpful for identifying people at higher risk of a stroke in the future," said Dr. Teresa Tsang, a cardiologist who is part of the Mayo research team. "With prospective studies already under way, we hope to verify that certain simple, noninvasive echo measurements can help assess the risk of stroke, so prevention efforts can be implemented in those who will most benefit from them."

Heart attack? Maybe not

Another new study presented at the ASE meeting showed that an ultrasound technique called myocardial contrast echocardiography (MCE) can quickly tell emergency room physicians whether a patient's chest pain is cardiac-related. Using MCE can lead to more effective treatment, quicker discharge times and lower treatment costs, the study said.

More than 5 million people go to the emergency room each year because of chest pain, but only some 1.2 million of them are shown to have heart attacks. It may take as much as 12 hours of hospitalization to rule out a heart attack. In search of a better alternative, a team of researchers at the University of Virginia Health System (Charlottesville, Virginia) used MCE alongside standard diagnostic procedures to evaluate 898 patients who came to the emergency room with chest pain. Using MCE, researchers observed left ventricular wall thickness and blood flow within the heart muscle and were able to accurately rule out cardiac causes – immediately and at bedside – as the root of symptoms in 445 patients in the sample group. The study also found that MCE can save money.

"Our findings confirm the belief that MCE can enable a quicker diagnosis of cardiac chest pain and make a case for wider use of myocardial contrast echocardiography in emergency departments," said Kevin Wei, MD, a cardiologist and the primary researcher on the study. "With MCE, doctors can provide more effective care, manage their patient loads more efficiently and prevent unnecessary costs to patients."

Intracardiac vs. conventional monitoring

Transcatheter closure of interatrial communications is an alternative to anticoagulant or antiaggregant therapy and surgical closure of the defects. A certain risk of severe complication remains. Some complications are the result of suboptimal device performance, but they may also be related to discontinuous echocardiographic monitoring. Supine patients do not tolerate continuous monitoring with transesophageal echocardiography (TEE) well unless they are sedated or under general anesthesia. Intracardiac echocardiography (ICE) is proposed as an alternative method to guide percutaneous device closure.

As shown in a reprint from Circulation (February 2003) and discussed during the ASE, results show ICE to be superior to TEE. Transcatheter closure, including the diagnostic part of the procedure, can be guided continuously without need for general anesthesia. Fluoroscopy time can be shortened to less than six minutes, a factor of utmost importance in young patients who are frequently candidates for device closure of atrial defects.

ICE results in much lower stress to patients than TEE, and ICE depicts the individual morphology of the interatrial communication and the instrumentation needed for device closure in fullest detail.

Broadening the adoption curve

While many established cardiologists are reluctant to use contrast in their work, GE Healthcare (Chalfont St. Giles, UK) hopes to increase the slope of the contrast adoption curve through its acquisition of Amersham Health (Buckinghamshire, UK). Now world-leading hardware is combined with a second-generation medical diagnostic product Optison, a contrast medium.

Optison (perflutren protein-type A microspheres for injection, USP) is well-established, with a robust capability to image the endocardial borders of the heart. This allows physicians to see abnormalities in the walls of the heart during an ultrasound scanning procedure, enabling more accurate diagnosis of the patient's heart condition and providing guidance for the selection and monitoring of treatment.

Suboptimal ultrasound exams are common. Optison is claimed to significantly improve imaging so that a majority of suboptimal exams can be converted to usable diagnostic echograms. GE said it improve left ventricular endocardial border delineation in 93% of patients studied.

The Acuson AcuNav Diagnostic Ultrasound Catheter from Siemens Medical Systems (Issaquah, Washington) brings echocardiologists another ultrasound choice. This advanced ultrasound catheter provides a real-time visual map of the entire heart. The company says it believes the AcuNav provides greater insights into cardiac anatomy than X-ray, fluoroscopy or transesophageal echo. Other devices can be imaged while inside the heart with superior clarity. A physician can view tissue motion and blood flow dynamics precisely and in real time.

The AcuNav can help visualization of clinical complications that may occur in some procedures such as pericardial effusion, clot detection and therapeutic device mispositioning – significant issues for cardiologists.

Internet cardiology

Medcon Telemedicine Technology (Whippany, New Jersey) offers eMedcon – a secure, web-based telecardiology referral and consultation application. The system promises to eliminate time and distance constraints while delivering images and reports to referring physicians. Lowell Satler, MD, associate director of cardiac cath labs at Washington Hospital Center (Washington) said, "As the only Internet telecardiology solution on the market, eMedcon was – and still is – the only product that truly met our needs. eMedcon has significantly enhanced our referral volume."

Medcon's TCS Symphony software system orchestrates images and patient information from all cardiology imaging modalities and information sources into one central system. The company says it believes it simplifies the natural cardiology workflow and improves cost-effectiveness so that healthcare professionals can focus on what they do best, helping people.

TCS Symphony's modular approach support tailor-made and scalable solutions to address customers' needs – from enterprise-wide cardiology departments in large institutions to single viewing stations at home.