MUNICH, Germany — The noise and confusion from the bells and whistles being added to cardiology imaging are driving growth and greater revenues for manufacturers, but far more importantly, the steady stream of upgrades and new features is bringing breakthroughs in medical practice.

Scientific sessions featuring abstracts and research papers using high-tech modalities for imaging the human heart have grown to more than 20% of the total 363 scientific sessions over the four days of the European Society of Cardiology's (ESC; Sophia Antipolis, France) annual congress, which ended here last Wednesday.

It is a full-scale revolution in clinical practice, accelerating at a breakneck speed that is slowed only by the strict discipline of evidence-based practice.

To put it another way, cardiologists simply have never seen such depth and detail on every component of the beating heart and pumping coronary arteries, simultaneously viewing anatomy, function and perfusion.

More startling, these vivid images are not abstract research but right-now 4-D pictures from inside the chest of the living and breathing — and suffering — patient lying on the examination table.

The profusion of panel discussions at the congress was a precursor to the necessary steps toward setting what will someday be guidelines for integrating imaging into clinical practice.

Yet even as cardiologists struggle to focus on the known modalities and their applications, the horizon continues to expand further and further out.

To infinity and beyond!

At ESC the cutting edge of integrating imaging and intervention technologies was presented in a session showing how magnetic navigation systems (MNS), already established in electrophysiology, are now being extended to other applications in cardiology, including percutaneous interventions and the delivery of stem cells.

In MNS, two large magnets positioned at either side of a patient create fields capable of generating sufficient force to steer magnetically tipped interventional devices through the vasculature while real-time fluoroscopy displays a road map on a display — allowing the surgeon to guide the device from a remote room to controlled catheter ablation.

Professor Luc Jordaens from Rotterdam, the Netherlands, told cardiologists that MNS allows for extremely precise catheter movements, decreased procedure time and the opportunity to couple catheters with 3-D imaging.

The approach also decreases the number of catheters needed, results in fewer complications at puncture sites, and reduces fluoroscopic exposure for both patients and physicians.

Potential applications for the MNS platform beyond ablation include positioning pacing wires and replacing valves.

"One of the real advantages is that MNS catheters are like floppy spaghetti, so there's virtually no risk of perforation," Jordaens said.

Sabine Ernst of the Royal Brompton and Harefield Hospital (London) said, "Ultimately, the remoteness of the technique is likely to increase. If you can do the procedure from the next room, there's absolutely no reason why you couldn't perform it from another city, or even another planet."

Coming back to earth

Frank Rademakers, MD, of University Hospitals (Leuven, Belgium), in a session titled "Imaging: The Focus of Clinical Cardiology for Years to Come," told cardiologists: "It is time to start focusing again, not on what we can image, but on what we need to image to improve patient diagnosis and outcome."

New techniques are welcome and dearly needed in many areas, he said, "but we have to create evidence showing an incremental value above existing techniques before including them in everyday practice."

Rademakers said cardiologists need to recognize a new subspecialty, the "cardiovascular imager," to integrate the waves of information coming from various techniques into a consistent answer to the clinicians.

"This requires broad consensus-building among the different modalities and specialties and much more research into the area, but it is necessary to translate today's expanding imaging capabilities into a benefit for the cardiovascular patient," he said.

Meanwhile the drumbeat from industry continued during the ESC congress, with more announcements of even newer capabilities.

Full volume 'echo in a heartbeat' from Siemens

Another new product from Siemens (Erlangen, Germany) shown on the ESC exhibit floor was the Acuson SC2000, the world's first echocardiography system to acquire instantaneous, non-stitched full-volume images of the heart in a single heartbeat.

A significant achievement, a bold statement and a marketing claim with a short life expectancy.

Promoted as "Echo in a Heartbeat," the Acuson SC2000 is a full-volume imaging ultrasound system acquiring non-stitched, real-time, full-volume 3-D images.

Siemens was clearly proud of getting to market first with this capability, comparing it to the landmark moment in 1953 when echocardiography pioneers Inge Edler and Hellmuth Hertz acquired the world's first cardiac ultrasound recording using Siemens technology.

Aquiring the heart in 90-degree pyramids in one second, every second dramatically reduces acquisition time, thereby improving workflow in the echocardiography suite.

In other words, higher patient throughput, which translates into reduced waiting lists for patients and higher revenues for clinics.

Siemens' patented Coherent Volume Formation technology uses simultaneous, multiple beam acquisition on the Acuson SC2000 rather than the current standard for serial line-by-line acquisition.

This paradigm shift, coupled with the jacked-up Siemens 4Z1c transducer, which runs at over-the-limit power output thanks to a cooling technology that keeps it inside the regulatory limits, gives improved penetration, reduced noise and high-volume acquisition rates when compared to conventional 3-D transducers.

This muscular combination also can juggle volume imaging, 2-D, M-mode, color Doppler and spectral Doppler modalities.

This new high-end system for cardiological examinations will "very likely" be available in Europe this fall, the company said.

IQ-SPECT is on the way

Siemens also was showing a work-in-progress called IQ-SPECT with a SMARTzoom, a collimator engineered to magnify the heart while imaging the rest of the torso in the usual manner. With SPECT, the patient radiates the machine and not the other way around, as with computer tomography (CT).

Injected with a radioactive formulation, the function of the patient's organs become visible to the gamma detectors that render the radiation into a light image for humans to view. The resulting images, sliced in the same way as CT images, can shows a cardiologist where tissue is viable and where it is not, as in the case of muscles that are no longer working.

The high-resolution images of the IQ-Spect sharply indicate the vivid activity of active muscle tissue and the somber zones of dead tissue.

Indicating dead tissue can be extremely useful for a cardiologist, who may decide to forego the bypass of a vessel as there is no point pumping fresh blood to muscles that won't accept it.

Cardiac SPECT data is currently obtained with gantries positioning the detectors at 90 degrees to the body which then rotate centered mechanically on the middle of the table as the patient tries to lay perfectly still.

With IQ-SPECT, Siemens re-engineered the mechanics of the Symbia S and T gantries allow an organ centric detector rotation where the detectors shift off the fixed centerline to focus on a specific organ. The heart, for example, is on the left side of the chest cavity and not in the center.

Putting the heart at the center of the oribtal axis of the gamma detectors focus makes the capture of radiation from the patient's heart more efficient, thereby "magnifying" it, while reducing truncations and artifacts.

The efficiency of the IQ-SPECT also makes it faster. Engineers at the Siemens booth told Diagnostics & Imaging Week the acquisition is almost four times quicker, reducing from 15 minutes to four minutes the time a patient needs to lie as perfectly still as possible.

Faster acquisition is good for everyone. Patients do not have to lay unnaturally rigid for a prolonged period and the radiology center is able to put through a greater number of patients.

Designed as an upgrade feature for the Siemens Symbia series, IQ-SPECT is field-upgradeable for the T-model that is a dual-modality unit with SPECT detectors and a CT, or the S-series that is a stand-alone SPECT unit

Siemens engineers said there are "several hundred Symbia systems installed around the world."

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