Role of impaired iron transport on exercise performance in heart failure patients

Aims

Impaired iron transport (IIT) occurs frequently in heart failure (HF) patients, even in the absence of anaemia and it is associated with a poor quality of life and prognosis. The impact of IIT on exercise capacity, as assessed by the cardiopulmonary exercise test (CPET), in HF is at present unknown. The aim of this article is to evaluate in HF patients the impact on exercise performance of IIT, defined as transferrin saturation (TSAT) <20%.

Methods and results

We collected data of 676 patients hospitalised for HF. All underwent laboratory analysis, cardiac ultrasound, and CPET. Patients were grouped by the presence/absence of IIT and anaemia (haemoglobin <13 and <12 g/dL in male and female, respectively): Group 1 (G1) no anaemia, no IIT; Group 2 (G2) anaemia, no IIT; Group 3 (G3) no anaemia, IIT; Group 4 (G4) anaemia and IIT. Peak oxygen uptake (peakVO2) reduced from G1 to G3 and from G2 to G4 (G1: 1266±497 mL/min, G2: 1011±385 mL/min, G3: 1041±395 mL/min, G4: 833±241 mL/min), whereas the ventilation to carbon dioxide relationship slope (VE/VCO2 slope) increased (G1: 31.8±7.5, G2: 34.5±7.4, G3: 36.1±10.2, G4: 37.5±8.4). At multivariate regression analysis, peakVO2 independent predictors were anaemia, brain natriuretic peptide (BNP), and left ventricular ejection fraction, whereas VE/VCO2 slope independent predictors were IIT and BNP.

Conclusions

In HF IIT is associated with exercise performance impairment independently from anaemia, and it is a predictor of elevated VE/VCO2 slope, a pivotal index of HF prognosis.

Funding Acknowledgement

Type of funding sources: Private hospital(s). Main funding source(s): Centro cardiologico Monzino, Italy

Prosthesis-patient mismatch after aortic valve in valve procedure: incidence, predictors and clinical outcomes

Funding Acknowledgements

Type of funding sources: None.

Background. Transcatheter aortic valve-in-valve (TAVI ViV) implantation is an appealing treatment option for patients with degenerated bioprostheses. However, elevated residual gradients after TAVI ViV procedure are very common. These are an unwanted effects of prosthesis-patient mismatch (PPM). Currently, the actual incidenceof PPM, its predictors and its clinical outcomes have not been completely investigated.

Purpose. The aims of this study was to investigate the incidence, predictors and clinical outcome of PPM and therefore of elevated gradients after TAVI ViV.

Methods. 75 patients (age 78 ± 9 years, 36 male), who underwent TAVI-ViV due to failed aortic biological valve (60 stented, 15 stentless), were enrolled. Mechanism of bioprosthetic valve failure was stenosis (34 cases, 45%), regurgitation (24 cases, 32%) or combination (17 cases, 23%). Elevated residual gradients were defined as a mean DP> 20 mmHg. PPM was identified by the indexed effective orifice area (EOAi) measured by echocardiography (moderate PPM if 0.65 < EOAi < 0.85 cm²/m²; severe PPM if EOAi < 0.6 cm²/m²).

Results. ViV TAVI was feasible in all patients, 33 patients (44%) were implanted with a balloon-expandable valve and 42 (56%) with a self-expandable valve. Post-procedural post-ballooning was performed in 16 out of 42 patients (38%) receiving a self-expandable valve. Post-operative mean DP> 20 mmHg was found in 35 patients (48%). Moderate PPM was found in 24 cases (33%) and severe PPM in 15 (20%). A logistic regression analyses identified small size of surgical prosthesis (size < 23 mm) [OR: 6.061(2.127-17.267), p = 0.001] and failed stented valve [OR: 20.727(2.522-170.364), p = 0.005] as independent predictors for the occurrence PPM. Interestingly PPM did not affect early and 1 years mortality (1 years mortality 1.3 %), while mortality was higher in pts with stentless prostheses (9%)

Conclusions. PPM is a frequent finding after ViV procedures. Despite elevated residual gradients, TAVI ViV resolved prosthetic dysfunction and PPM did not affect mortality.  Therefore, this procedure represents a promising new option for patients with failed biological prosthetic valves.