Now it's easy and comfortable
for the patient to test heart rate
Device Tests Cardiac Resynchronization Therapy During Exercise
June 02, 2009
A new device, called the Shape-HF Cardiopulmonary Testing System, cleared by FDA in April, optimizes heart failure therapy for people using pacemakers.
The Shape-HF system helps physicians quantify shortness of breath, measure patient response to therapy, define patient functional classification, track patient progress, and predict the patient's hospitalization risk," Clarence Johnson, Shape-HF's president (St Paul, MN), tells DOTmed News.
Dean MacCarter, Ph.D., the company's vice president, Clinical Affairs, introduced the device at the Heart Rhythm Society's 30th Annual Scientific Meeting May 13-16 in Boston, MA.
Dr. MacCarter noted that "what makes the Shape-HF different is how intuitive the device is; how easy and quick it is to use in the clinic, office or hospital setting; and most importantly, it requires very low exercise exertion. Even high risk patients can be tested with minimal discomfort," he told physicians at the heart rhythm meeting.
Shortness of breath on even mild exertion is a key symptom in heart failure, Dr. MacCarter adds. "We know that a positive response to CRT therapy improves breathing efficiency during exercise, so it makes sense that parameters that can measure patient breathing efficiency can be used to determine the proper CRT settings."
The system's test involves walking on a treadmill at a very low intensity of one mile per hour with the treadmill set at a 2 percent grade.
As patients exercise at a steady state heart rate, the physician adjusts therapy settings every two minutes, enough time for the adjustments to be reflected in breathing physiology. At the end of the test, during which four to five therapy settings are tested, the system uses a proprietary computer algorithm to rank the physiological response to exercise at each setting. The physician then reviews the results and chooses the therapy setting he or she believes is most appropriate for the patient. The patient also feels better, has less shortness of breath, and finds it easier to exercise, Mr. Johnson says.