Prediction of mortality by VE/VCO2 slope in heart failure: A metanalysis of published data

ROSANA POGGIO; HERNÁN COHEN ARAZI; SANTIAGO G. MIRIUKA

Orlando, USA

Congreso; American Heart Association Scientific Meeting 2009; 2009

Background: The evaluation in a cardiopulmonary stress test of maximal oxygen consumption (PeakVO2) and VE/VCO2 are frequently used as prognostic markers in heart failure. Traditionally, PeakVO2 has been considered as the gold standard for prediction of death. However, several studies suggest that VE/VCO2 is at least as good as PeakVO2. Our goal was to systematically review the published papers on VE/VCO2 and prognosis in HF and to compare it with PeakVO2. Methods: We performed a metanalysis of diagnostic studies. We searched PubMed and ISI Web of Science for papers related to VE/VCO2. The end-point was death. Studies were excluded if we were unable to determine sensibility (Se) and specificity (Sp), duplicated publications, or lack of information about the specified endpoint. We analyzed the selected studies for Se, Sp, diagnostic odds ratio (DOR) and developed a summary ROC curve. We used the Meta-disc 1.4 software. Results: Our strategy retrieved 478 possible studies and we further selected 92 for analysis. After exclusion criteria, we were left with 13 studies. Total patients enrolled were 3013, with a median age of 57 years (52-59), 80% (72-87%) were male, 64% in NYHA functional class I-II, 51% (35-58%) with ischemic cardiomyopathy and a median ejection fraction of 29% (27-32). Cut-off values were 35 (range 32-45) for VE/VCO2 and 14 ml/kg/min (13-16) for PeakVO2. Median follow-up time was 31 months (24-39). Overall, Se was 0.67 (IC95%: 0.64-0.71), and Sp was 0.73 (0.71-0.75). DOR was 5.09 (4.15-6.24) and AUC was 0.75 (0.73-0.78). We selected seven papers with information to compare prognostic performance of VE/VCO2 and PeakVO2. Total number of patients was 2171. Results are shown in the table. S E DOR AUC VE/VCO2 slope 0.67 (0.64-0.71) 0.73 (0.71-0.75) 5.09 (4.15-6.24) 0.75 (0.73-0.78) VO2Max 0.67 (0.62-0.71) 0.65 (0.62-0.67) 3.81 (2.67- 5.43) 0.71 (0.66- 0.77) Conclusions: This metanalysis suggest that PeakVO2 and VE/VCO2 are similar in prediction of death in heart failure.