Sex differences in Cardiorenal Syndrome: Insights from CARDIOREN Registry

PURPOSE OF THE WORK

Although sex-specific differences in heart failure (HF) or kidney disease (KD) have been analyzed separately, the predominant cardiorenal phenotype by sex has not been described. This study aims to explore the sex-related differences in cardiorenal syndrome (CRS) in a contemporary cohort of outpatients with HF.

FINDINGS

An analysis of the Cardiorenal Spanish registry (CARDIOREN) was performed. CARDIOREN Registry is a prospective multicenter observational registry including 1107 chronic ambulatory HF patients (37% females) from 13 Spanish HF clinics. Estimated Glomerular Filtration Rate (eGFR) < 60 ml/min/1.73 m² was present in 59.1% of the overall HF population, being this prevalence higher in the female population (63.2% vs. 56.6%, p = 0.032, median age: 81 years old, IQR:74-86). Among those with kidney dysfunction, women displayed higher odds of showing HF with preserved ejection fraction (HFpEF) (odds ratio [OR] = 4.07; confidence interval [CI] 95%: 2.65-6.25, p < 0.001), prior valvular heart disease (OR = 1.76; CI 95%:1.13-2.75, p = 0.014), anemia (OR: 2.02; CI 95%:1.30-3.14, p = 0.002), more advanced kidney disease (OR for CKD stage 3: 1.81; CI 95%:1.04-3.13, p = 0.034; OR for CKD stage 4: 2.49, CI 95%:1.31-4.70, p = 0.004) and clinical features of congestion (OR:1.51; CI 95%: 1.02-2.25, p = 0.039). On the contrary, males with cardiorenal disease showed higher odds of presenting HF with reduced ejection fraction (HFrEF) (OR:3.13; CI 95%: 1.90-5.16, p < 0.005), ischemic cardiomyopathy (OR:2.17; CI 95%: 1.31-3.61, p = 0.003), hypertension (OR = 2.11; CI 95%:1.18-3.78, p = 0.009), atrial fibrillation (OR:1.71; CI 95%: 1.06-2.75, p = 0.025), and hyperkalemia (OR:2.43, CI 95%: 1.31-4.50, p = 0.005). In this contemporary registry of chronic ambulatory HF patients, we observed sex-related differences in patients with combined heart and kidney disease. The emerging cardiorenal phenotype characterized by advanced CKD, congestion, and HFpEF was predominantly observed in women, whereas HFrEF, ischemic etiology, hypertension, hyperkalemia, and atrial fibrillation were more frequently observed in men.

Determinants of maximal oxygen uptake in patients with heart failure

Aims

Maximum oxygen uptake (VO_2max) is an essential parameter to assess functional capacity of patients with heart failure (HF). We aimed to identify clinical factors that determine its value, as they have not been well characterized yet.

Methods

We conducted a retrospective, observational, single‐centre study of 362 consecutive patients with HF who underwent cardiopulmonary exercise testing (CPET) as part of standard clinical assessment since 2009–2019. CPET was performed on treadmill, according to Bruce's protocol (n = 360) or Naughton's protocol (n = 2). We performed multivariable linear regression analyses in order to identify independent clinical predictors associated with peak VO_2max.

Results

Mean age of study patients was 57.3 ± 10.9 years, mean left ventricular ejection fraction was 32.8 ± 14.2%, and mean VO_2max was 19.8 ± 5.2 mL/kg/min. Eighty‐nine (24.6%) patients were women, and 114 (31.5%) had ischaemic heart disease. Multivariable linear regression analysis identified six independent clinical predictors of VO_2max, including NYHA class (B coefficient = −2.585; P < 0.001), age (B coefficient per 1 year = −0.104; P < 0.001), tricuspid annulus plane systolic excursion (B coefficient per 1 mm = +0.209; P < 0.001), body mass index (B coefficient per 1 kg/m² = −0.172; P = 0.002), haemoglobin (B coefficient per 1 g/dL = +0.418; P = 0.007) and NT‐proBNP (B coefficient per 1000 pg/mL = −0.142; P = 0.019).

Conclusions

The severity of HF (NYHA class, NT‐proBNP) as well as age, body composition and haemoglobin levels influence significantly exercise capacity. In patients with HF, the right ventricular systolic function is of greater importance for the physical capacity than the left ventricular systolic function.