Differential contribution of dead space ventilation and low arterial pCO2 to exercise hyperpnea in patients with chronic heart failure secondary to ischemic or idiopathic dilated cardiomyopathy
| Autor: | Stephanie Bayne, Stefan D. Anker, Panagiota Georgiadou, Darrel P. Francis, Andrew J.S. Coats, Adam C. Scott, Sabine Genth-Zotz, Roland Wensel, Massimo F. Piepoli |
|---|---|
| Rok vydání: | 2004 |
| Předmět: |
Cardiomyopathy
Dilated Male medicine.medical_specialty Partial Pressure Myocardial Ischemia Hyperpnea Hypercapnia Internal medicine Idiopathic dilated cardiomyopathy medicine Humans Tidal volume Aged Ejection fraction business.industry VO2 max Respiratory Dead Space Carbon Dioxide Middle Aged medicine.disease Pulmonary Alveoli Heart failure Exercise Test Cardiology Breathing Female Acidosis Respiratory Blood Gas Analysis medicine.symptom Pulmonary Ventilation Cardiology and Cardiovascular Medicine business human activities |
| Zdroj: | The American Journal of Cardiology. 93:318-323 |
| ISSN: | 0002-9149 |
| DOI: | 10.1016/j.amjcard.2003.10.011 |
| Popis: | In chronic heart failure (CHF), the abnormally large ventilatory response to exercise (VE/VCO(2) slope) has 2 conceptual elements: the requirement of restraining arterial partial pressure of carbon dioxide (pCO(2)) from increasing (because of an increased ratio between increased physiologic dead space and tidal volume [VD/VT]) and the depression of arterial pCO(2) by further increased ventilation, which necessarily implies an important non-carbon dioxide stimulus to ventilation. We aimed to assess the contribution of these 2 factors in determining the elevated VE/VCO(2) slope in CHF. Thirty patients with CHF underwent cardiopulmonary exercise testing (age 65 +/- 11 years, left ventricular ejection fraction 34 +/- 15%, peak oxygen uptake 15.2 +/- 4 ml/kg/min, VE/VCO(2) slope 36.4). At rest and during exercise, arterial pCO(2) was measured and VD was calculated and separated into serial and alveolar components. VD/VT decreased from 0.57 at rest to 0.44 at peak exercise (p |
| Databáze: | OpenAIRE |
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