News | April 07, 2010

Study Finds Ventilatory Efficiency More Accurately IDs Heart Transplant Candidates

April 7, 2010 – A study concludes ventilator efficiency (VE/VCO2 slope) is more accurate than the current listing criteria for heart transplantation in identifying patients likely to derive a survival benefit from such intervention. The results were recently published in Circulation Heart Failure, a journal of the American Heart Association.

The study conclusions reinforce the science behind the Shape-HFTM Cardiopulmonary Exercise Testing system, which measures ventilation parameters including ventilatory efficiency. Cardiopulmonary exercise testing (CPX) has been used for many years to help doctors understand the severity and prognosis in patients with chronic heart failure. Peak CPX testing can guide physicians in their clinical decision-making, but conducting CPX tests at such levels comes with its own set of problems such as maximal physical effort by the patient, specialized training, and interpretation challenges.

A total of 663 chronic heart failure patients who underwent cardiopulmonary exercise testing were tracked for cardiac mortality and heart transplantation. Symptom-limited CPX testing was performed on all patients. Oxygen uptake (VO2), carbon dioxide production (VCO2) and minute ventilation (VE) were measured on a breath-by-breath basis. Peak VO2 was defined as the highest 20- to 30-second average achieved during exercise. Patients were evaluated for the occurrence of death or heart transplantation. Follow-up was right-censored at three years.

Results showed that using a VE/VCO2 slope threshold instead of the current exercise criteria would classify 39 more subjects as high-risk, correctly identifying 19 more patients who died during follow-up, and 16 others who underwent transplantation. VE/VCO2 slope provided significant discrimination between the three years survival of both high- and low-risk patients relative to post-transplant patients. Re-analysis of survival data using death or heart transplantation as endpoint showed similar results.
The Shape-HF System is the first gas exchange testing device specifically designed for cardiology. It measures a patient’s functional capacity and quantifies the severity of dyspnea on exertion. The test takes 15 minutes and involves measuring ventilation parameters while the patient exercises on a treadmill at a very low intensity. The test also quantifies the heart rate response to exercise to determine if it is appropriate and can unmask potential co-morbidities that may adversely affect heart failure prognosis or therapy response.

Shape-HF measures cardiopulmonary gas exchange quickly without undue strain on the patient. It can be used in the office setting and provides real-time physiological assessment to help physicians elucidate the physiological underpinnings of dyspnea, objectively assess patient functional classification, monitor therapy response and progress, identify potential comorbidities, and optimize cardiac resynchronization therapy at exercise levels consistent with patient daily activity.

For more information: http://circheartfailure.ahajournals.org

Related Content

High Intensity Exercise in Teenagers Could Ward Off Heart Disease

Ultrasound image of the carotid artery. Lines in yellow were used to determine arterial diameter and stretching before and following exercise.

News | Cardiac Diagnostics | July 16, 2018
New research published in Experimental Physiology has indicated potential differences in heart health benefits of...
News | Cardiac Diagnostics | June 14, 2018
A team of researchers says it has linked sensitivity to an allergen in red meat to the buildup of plaque in the...
The blood of patients with familial chylomicronemia syndrome (FCS) can appear milky in color (lipemic) due to the buildup of fat in their body. Image courtesy of Akcea Therapeutics.

The blood of patients with familial chylomicronemia syndrome (FCS) can appear milky in color (lipemic) due to the buildup of fat in their body. Image courtesy of Akcea Therapeutics.

 

Feature | Cardiac Diagnostics | May 07, 2018 | Steven D. Freedman, M.D., Ph.D.
 
Male Triathletes May Be Putting Their Heart Health at Risk
News | Cardiac Diagnostics | January 09, 2018
Competitive male triathletes face a higher risk of a potentially harmful heart condition called myocardial fibrosis,...
ERT Acquires iCardiac Technologies
News | Cardiac Diagnostics | December 19, 2017
ERT recently announced it has acquired iCardiac Technologies, a provider of centralized cardiac safety and respiratory...
New Study Suggests Protein Could Protect Against Coronary Artery Disease

Patients with no obstructed blood flow in the coronary arteries had higher levels of CXCL5 (blue) compared to patients with moderate levels (green) or lower levels (yellow) of CXCL5, who had increased severity of coronary obstructions (indicated by the arrows). Credit: Schisler lab

News | Cardiac Diagnostics | December 07, 2017
December 7, 2017 — The buildup of plaque in the heart’s arteries is an unfortunate part of aging.
E-cigarettes Most Likely to be Used by Alcohol Drinkers and Former Cigarette Smokers, at American Heart Association (AHA), #AHA2017.
News | Cardiac Diagnostics | December 06, 2017
December 6, 2017 — Electronic cigarettes are more frequently used by people who recently quit smoking and alcohol dri
Lack of sleep may cause heart disease in older women. American heart Association, #AHA2017
News | Cardiac Diagnostics | December 06, 2017
December 6, 2017 — Older women who do not get enough sleep were more likely to have poor cardiovascular health, accor
Overlay Init