PERIODIC BREATHING (EOV) ON CARDIORESPIRATORY STRESS TESTING: ARE THERE PROGNOSTIC DIFFERENCES BETWEEN PATIENTS WITH PERIODIC BREATHING THAT PERSISTS THROUGHOUT THE TEST AND PATIENTS TO WHOM IT DISAPPEARS?

Introduction Oscillatory exercise ventilation (EOV) is frequently seen in patients with severe heart failure (HF) and has a ne:gative prognostic value in both patients with reduced HF and those with average ejection fraction. Two types of EOV have been described one that lasts throughout exercise and one that disappears before the end of exercise, Figure 1 Aim of the Study It is currently unknown whether there are differences in prognosis and functional capacity between HF patients with EOV that persists or disappears during exercise. Population Male and female patients, aged≥18 years, diagnosed with HF and LVEF<45% were enrolled. Methods The retrospective study enrolled patients who performed a cardiopulmonary exercise test (CPET) and presented with EOV during exercise (Monzino Heart Center Laboratory and patients included in the MECKI score registry, identified a total of 255 patients). A subset of 100 patients underwent measurement of maximum inspiratory pressure (MIP) and maximum expiratory pressure (MEP) before and after exercise (Table 2). All patients were treated at the top of therapy for HF. CPETs were performed and analyzed with a standard approach using a customized ramp protocol. The main parameters obtained are reported and compared in Table 1. EOV was defined according to as a cyclic fluctuation in ventilation as proposed by Corrà et al. Statistical analysis:Data are reported as mean ± standard deviation or median and interquartile range as appropriate. The two groups of patients were compared by t test for unpaired data in the case of data with normal distribution. Mortality was analyzed by Kaplan Meier curves and Log Rank test. Survival was considered using the composite end–point of cardiovascular death, urgent cardiac transplantation, or implantation of a left ventricular assist device. The median MECKI score of the total population was 5.5% (2.5–13.7) with no significant differences between the 2 groups. Figure 1 shows the Kaplan Meyer describing the 5–year survival analysis in both groups. Conclusions Patients with disappearing EOV demonstrated better exercise performance but no significant difference in survival and major prognostic parameters.