The American journal of cardiology
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Comparative Study
Comparison of baseline characteristics and one-year outcomes between African-Americans and Caucasians undergoing percutaneous coronary intervention.
The objectives of this study were to determine whether there are race-based differences in baseline characteristics and in short- or long-term outcomes after percutaneous coronary intervention (PCI). African-Americans have a higher incidence of coronary artery disease but are less likely to undergo coronary revascularization than Caucasians. Little is known about the profiles and outcomes of African-Americans who undergo PCI. ⋯ In multivariate analysis, African-American race remained a significant predictor of increased 1-year mortality (hazard ratio 1.35, 95% confidence interval 1.06 to 1.71, p = 0.01). African-Americans undergoing angioplasty have more co-morbid baseline conditions than Caucasians. Despite similar clinical success, 1-year outcomes are impaired in African-Americans.
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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). ⋯ Despite this, arterial pCO(2) was not related to peak oxygen uptake (r = 0.2) or to arterial lactate (r = -0.25) and only weakly to New York Heart Association functional class (F = 3.7). First, the increased VE/VCO(2) slope was caused by both the high VD/VT ratio and by other mechanisms, as shown by low arterial pCO(2) during exercise. Second, this latter component (depression of arterial pCO(2)) was not related to conventional measures of heart failure severity.