Carvedilol and metoprolol did not improve the VE/VCO2 slope overall, but carvedilol was more effective than metoprolol in improving the slope in patients with baseline BNP >63 pg/ml (p<0.05).
RCT (n=57)
randomized
Does carvedilol improve exercise ventilatory efficiency (VE/VCO2 slope) compared to metoprolol in patients with congestive heart failure?
While neither beta-blocker improved exercise ventilatory efficiency in the overall mild heart failure cohort, carvedilol may offer superior improvement in VE/VCO2 slope compared to metoprolol in patients with more advanced disease (higher BNP).
BACKGROUND: The slope of the relationship between ventilation and carbon dioxide production (VE/VCO2 slope), obtained during symptom-limited ramp exercise testing, reflects exercise ventilatory efficiency. Importantly, the VE/VCO2 slope is related to prognosis in patients with congestive heart failure (CHF). The aim of the present study was to determine the relationship between the institution of beta-blockers, carvedilol or metoprolol, and the VE/VCO2 slope during exercise in patients with CHF. METHODS AND RESULTS: Fifty-seven patients with New York Heart Association functional class II or III with a radionuclide left ventricular ejection fraction (LVEF) of less than 40% received carvedilol or metoprolol in a randomized fashion. The VE/VCO2 slope, LVEF and plasma brain natriuretic peptide (BNP) concentration were determined before and after 16 weeks of treatment. LVEF improved (p63 pg/ml (respective baseline median values) (p63 pg/ml, the improvement effect on the VE/VCO2 slope with carvedilol was significantly greater than that with metoprolol (p<0.05) and a significant improvement in the VE/VCO2 slope was observed only in those who took carvedilol (p<0.01). CONCLUSIONS: The VE/VCO2 slope was not improved after beta-blocker therapy in any of the patients. However, it did improve in patients with a lower LVEF or higher BNP level at baseline, and carvedilol was more effective than metoprolol in improving the VE/VCO2 slope in patients with higher BNP levels at baseline.
Kataoka et al. (Tue,) conducted a rct in congestive heart failure (CHF) (n=57). carvedilol vs. metoprolol was evaluated on VE/VCO2 slope. Carvedilol and metoprolol did not improve the VE/VCO2 slope overall, but carvedilol was more effective than metoprolol in improving the slope in patients with baseline BNP >63 pg/ml (p<0.05).