Head-to-Head Comparison of Hepatic Vein and Superior Vena Cava Flow Velocity Waveform Analyses for Predicting Elevated Right Atrial Pressure.

OBJECTIVE: Blood flow in the hepatic veins and superior vena cava (SVC) reflects right heart filling; however, their Doppler profiles are often not identical, and no studies have compared their diagnostic efficacies. We aimed to determine which venous Doppler profile is reliable for detecting elevated right atrial pressure (RAP). METHODS: In 193 patients with cardiovascular diseases who underwent cardiac catheterization within 2 d of echocardiography, the hepatic vein systolic filling fraction (HV-SFF) and the ratio of the peak systolic to diastolic forward velocities of the SVC (SVC-S/D) were measured. HV-SFF < 55% and SVC-S/D < 1.9 were regarded as elevated RAP. We also calculated the fibrosis 4 index (FIB-4) as a serum liver fibrosis marker. RESULTS: HV-SFF and SVC-S/D were feasible in 177 (92%) and 173 (90%) patients, respectively. In the 161 patients in whom both venous Doppler waveforms could be measured, HV-SFF and SVC-S/D were inversely correlated with RAP (r = -0.350, p < 0.001; r = -0.430, p < 0.001, respectively). SVC-S/D > 1.9 showed a significantly higher diagnostic accuracy of RAP elevation compared with HV-SFF < 55% (area under the curve, 0.842 vs. 0.614, p < 0.001). Multivariate analyses showed that both FIB-4 (ß = -0.211, p = 0.013) and mean RAP (ß = -0.319, p < 0.001) were independent determinants of HV-SFF. In contrast, not FIB-4 but mean RAP (ß = -0.471, p < 0.001) was an independent determinant of SVC-S/D. The diagnostic accuracy remained unchanged when HV-SFF < 55% was considered in conjunction with the estimated RAP based on the inferior vena cava morphology. Conversely, SVC-S/D showed an incremental diagnostic value over the estimated RAP. CONCLUSIONS: SVC-S/D enabled a more accurate diagnosis of RAP elevation than HV-SFF.

Exercise Capacity and Clinical Outcomes in Chronic Heart Failure Patients with Mild Tricuspid Regurgitation.

AIM: The present study aimed to investigate the impact of mild tricuspid regurgitation (TR) on the exercise capacity or clinical outcomes in patients with chronic heart failure (CHF). METHODS AND RESULTS: The study enrolled 511 patients with CHF who underwent cardiopulmonary exercise testing (CPET) between 2013 and 2018. The primary outcome was a composite of heart failure hospitalization and death. Patients with mild TR (n = 324) or significant TR (moderate or greater; n = 60) displayed worse NHYA class and reduced exercise capacity on CPET than those with non-TR (n = 127), but these were more severely impaired in patients with significant TR. A total of 90 patients experienced events over a median follow-up period of 3.3 (interquartile range 0.8-5.5) years. Patients with significant TR displayed a higher risk of events, while patients with mild TR had a 3.0-fold higher risk of events than patients with non-TR (hazard ratio (HR) 3.01; 95% confidence interval (CI), 1.50-6.07). Multivariate Cox regression analysis showed that, compared with non-TR, mild TR was associated with increased adverse events, even after adjustment for co-variates (HR 2.97; 95% CI, 1.35-6.55). CONCLUSIONS: TR severity was associated with worse symptoms, reduced exercise capacity, and poor clinical outcomes. Even patients with mild TR had worse clinical characteristics than those with non-TR.

Impact of Cardiac Power Output on Exercise Capacity and Clinical Outcome in Patients With Chronic Heart Failure.

Less data are available regarding the impact of cardiac power output on exercise capacity or clinical outcome in patients with chronic heart failure (CHF). The study enrolled 280 consecutive patients with CHF referred for cardiopulmonary exercise testing and right-sided heart catheterization between 2013 and 2018. The primary outcome was composite of heart failure hospitalization or death. Cardiac power output was calculated as (mean arterial pressure × CO) ÷ 451. Patients with low cardiac power output (<0.53 W, n = 99) were older and had a higher brain natriuretic peptide level than patients with high cardiac power output (≥0.53W, n = 181). Cardiac power output was correlated with peak oxygen consumption (peak V̇O2), peak workload achievement, and ventilatory efficiency (V̇E/V̇CO2 slope) in cardiopulmonary exercise testing, whereas each of cardiac output or mean arterial pressure was not. There were 48 patients with events over a median follow-up period of 3.5 (interquartile range 1.0 to 6.0) years. Patients with low cardiac power output had about a 2-fold higher risk of events than those with a high cardiac power output (hazard ratio 1.97, 95% confidence interval 1.12 to 3.48). In the multivariable Cox regression, a 0.1-W decrease in cardiac power output was associated with 19% increased adverse events (hazard ratio 0.81, 95% confidence interval 0.67 to 0.99). In conclusion, cardiac power output was associated with reduced exercise capacity and poor clinical outcome, suggesting that cardiac power output is useful for risk stratification in patients with CHF. Further study is required to identify therapies targeting cardiac power output to improve the exercise capacity or clinical outcome in patients with CHF.

Prognostic Significance of Peak Workload-to-Weight Ratio by Cardiopulmonary Exercise Testing in Chronic Heart Failure.

The prognostic impact of peak workload-to-weight ratio (PWR) during cardiopulmonary exercise testing (CPET) and its determinants in patients with chronic heart failure (CHF) are not well understood. Consecutive 514 patients with CHF referred for CPET at the Hokkaido University Hospital between 2013 and 2018 were identified. The primary outcome was a composite of hospitalization because of worsening heart failure and death. PWR was calculated as peak workload normalized to body weight (W/kg) by CPET. Patients with low PWR (cut-off median 1.38 [W/kg], n = 257) were older and more anemic than those with high PWR (n = 257). In CPET, patients with low PWR displayed reduced peak oxygen consumption and impaired ventilatory efficiency compared with those with high PWR, whereas the peak respiratory exchange ratio was not significantly different between the 2 groups. There were 89 patients with events over a median follow-up period of 3.3 (interquartile range 0.8 to 5.5) years. The incidence of composite events was significantly higher in patients with low PWR than in those with high PWR (log-rank p <0.0001). In the multivariable Cox regression, lower PWR was associated with adverse events (hazard ratio 0.31, 95% confidence interval 0.13 to 0.73, p = 0.008). Low hemoglobin concentration was strongly related to impaired PWR (ß coefficient = 0.43, per 1 g/100 ml increased, p <0.0001). In conclusion, PWR was associated with worse clinical outcomes, where blood hemoglobin was strongly related to PWR. Further study is required to identify therapies targeting peak workload achievements in exercise stress tests to improve the outcome in patients with CHF.