Importance of chronotropic response and left ventricular long-axis function for exercise performance in patients with heart failure and preserved ejection fraction.

We evaluated the relationship between the degree of chronotropic incompetence and left ventricular (LV) impairment during exercise with severity of exercise intolerance in patients with heart failure and preserved ejection fraction (HFPEF). All patients underwent exercise echocardiography during bicycle Ergometer exercise with the acquisition of long-axis tissue Doppler imaging (TDI). Peak heart rates during exercise were also recorded and the percentages of maximal age-predicted heart rate (%MPHR) and heart rate reserve (%HRR) were calculated thereby. Besides, cardiopulmonary exercise testing was performed with peak oxygen consumption (VO2) measuring averaged at the highest 30-second during exercise. Forty HFPEF patients (aged 65±9 years; 75% male) were divided into two groups according to the median of peak VO2: patients with peak VO2<16.5 and ≥16.5 ml/kg/min, respectively. Patients with lower peak VO2 had decreased peak heart rates, %MPHR, %HRR, stroke volume and cardiac indices (LVSI and LVCI) than those with higher peak VO2 (all p<0.05). The LV long-axis functions (TDI Sm, Em, s' and e') were reduced in patients with lower peak VO2 (all p<0.05). Moreover, peak VO2 correlated with the following parameters: peak heart rates, %MPHR, %HRR, LVSI, LVCI, TDI Sm, Em, s' and e'(all p<0.05). The degree of blunted chronotropic response and impaired LV long-axis function were more profound in HFPEF patients with poor exercise performance.

Wang J ，Fang F ，Yip GW ，Sanderson JE ，Feng W ，Xie JM ，Luo XX ，Lee AP ，Lam YY ... -  《-》

Determinants of Effort Intolerance in Patients With Heart Failure: Combined Echocardiography and Cardiopulmonary Stress Protocol.

The purpose of this study was to assess individual mechanisms of effort intolerance in patients with heart failure with preserved ejection fraction (HFpEF), heart failure with reduced ejection fraction (HFrEF), or normal cardiac function using combined echocardiography and cardiopulmonary stress testing. Combined stress echocardiography and cardiopulmonary tests visualize cardiac chambers in 4 well-defined activity levels (rest, unloaded, anaerobic threshold, and peak), allowing noninvasive assessment of cardiac function, hemodynamics, and arterial venous oxygen content difference (AVo(2)Diff) during all stages. Left ventricular volumes, stroke volume (SV), S', E/e', oxygen consumption (Vo(2)), and AVo(2)Diff were measured in all effort stages using ramp semirecumbent cycle prolonged (≥8 min) exercise in 45 consecutive subjects evaluated for effort intolerance (14 normal cardiac function, 16 HFpEF, and 15 HFrEF patients; age 56.5 ± 16 years; 73% male). In HFpEF and HFrEF, the changes in Vo2 were attenuated (between group p = 0.003; group by time interaction p < 0.0001), as well as peak heart rate (p = 0.0001; p = 0.0001) and SV (p = 0.006; p = 0.0001). End-diastolic volume to E/e' ratio (measure of compliance) was superior in HFrEF and normal patients at baseline but worsened in HFpEF and HFrEF at peak exercise (8.3 ± 4 vs. 11.6 ± 5 vs. 19.1 ± 8; p = 0.004; p = 0.01). Functional mitral regurgitation worsened even during the unloaded stage, mostly in patients with HFrEF, but also in several patients with HFpEF. In multivariable analysis, heart rate response (p = 0.007), and AVo(2)Diff (p < 0.0001) were the most significant independent predictors of effort capacity; SV was not. Combined tests are feasible and allow noninvasive evaluation of effort intolerance. In HFpEF and HFrEF patients, exercise intolerance is predominantly due to chronotropic incompetence and peripheral factors. Combined stress echocardiography and cardiopulmonary tests may have potential for clinical management and selection of patients for trials.

Shimiaie J ，Sherez J ，Aviram G ，Megidish R ，Viskin S ，Halkin A ，Ingbir M ，Nesher N ，Biner S ，Keren G ，Topilsky Y ... -  《-》

Left ventricular global longitudinal strain is associated with exercise capacity in failing hearts with preserved and reduced ejection fraction.

Hasselberg NE ，Haugaa KH ，Sarvari SI ，Gullestad L ，Andreassen AK ，Smiseth OA ，Edvardsen T ... -  《-》

Left ventricular diastolic dysfunction and exercise intolerance in obese heart failure with preserved ejection fraction.

Samuel TJ ，Kitzman DW ，Haykowsky MJ ，Upadhya B ，Brubaker P ，Nelson MB ，Hundley WG ，Nelson MD ... -  《-》

Functional iron deficiency and diastolic function in heart failure with preserved ejection fraction.

Functional iron deficiency (FID) is an independent risk factor for poor outcome in advanced heart failure with reduced EF, but its role in heart failure with preserved EF (HFPEF) remains unclear. We aimed to investigate the impact of FID on cardiac performance determined by pressure-volume loop analysis in HFPEF. 26 HFPEF patients who showed an increase in LV stiffness by pressure-volume (PV) loop analysis obtained by conductance-catheterization, performed exercise testing, echocardiographic examination including tissue Doppler and determination of iron metabolism: serum iron, ferritin and transferrin saturation. HFPEF patients who provided ferritin <100 μg/l or ferritin of 100-299 μg/l in combination with transferrin saturation <20% were defined as having FID. In 14 patients the expression of transferrin receptor was determined from available endomyocardial biopsies. Fifteen out of 26 HFPEF patients showed FID without anemia. Compared to control subjects and HFPEF patients without FID, HFPEF patients with FID showed an up-regulation of the myocardial transferrin receptor expression (p<0.05). No differences between HFPEF patients with and without iron deficiency were found in heart dimensions, systolic and diastolic function obtained by PV-loop and echocardiography analysis. According to the linear regression analysis, LV stiffness was correlated with peak oxygen uptake (r=-0.636, p<0.001) but not with the ferritin level or transferrin saturation. No relation was found between FID and exercise capacity. The association of LV stiffness with exercise performance was independent from the level of iron deficiency. In non-anemic HFPEF patients, cardiac dysfunction and impaired exercise capacity occur independently of FID.

Kasner M ，Aleksandrov AS ，Westermann D ，Lassner D ，Gross M ，von Haehling S ，Anker SD ，Schultheiss HP ，Tschöpe C ... -  《-》