Improved Prognostic Performance of Cardiac Power Output With Right Atrial Pressure: A Subanalysis of the ESCAPE Trial

Cardiac power output associated with hospitalization and mortality in coronary artery disease patients at stage B heart failure

Background

Cardiac power output (CPO) predicts outcomes in advanced heart failure (HF) and cardiogenic shock, but its role in early HF stages is unclear. This study assessed the prognostic value of CPO in coronary artery disease patients with asymptomatic left ventricular systolic dysfunction (ALVSD) at stage B HF.

Methods

We conducted a retrospective analysis of coronary artery disease patients who underwent coronary and pulmonary artery catheterization between 2006 and 2016. Stage B HF with ALVSD was defined as left ventricular ejection fraction < 50 %, without HF symptoms, signs, or prior HF hospitalization. CPO was derived from invasive hemodynamic parameters. Endpoints included HF hospitalization, cardiovascular mortality, and all-cause mortality over a 5-year follow-up.

Results

A total of 783 coronary artery disease patients with ALVSD at stage B HF were enrolled. Incidence rates (per 1000 person-years) were 13.9 for HF hospitalization, 14.5 for cardiovascular mortality, and 23.7 for all-cause mortality.Multivariate analysis adjusting for covariates demonstrated that CPO was independent associated with all endpoints. Patients with a low CPO (<0.97 Watts) were at significantly higher risk for HF hospitalization (adjusted hazard ratio [HR]: 4.04; 95 % CI: 1.53 - 10.6; p = 0.005), cardiovascular mortality (adjusted HR: 2.73; 95 % CI: 1.19 - 6.27; p = 0.018), and all-cause mortality (adjusted HR: 1.86; 95 % CI: 1.05 - 3.30; p = 0.035) compared to those with higher CPO, regardless of subgroup classification.

Conclusion

Resting CPO in patients with ALVSD is significantly associated with adverse events, including HF hospitalization and mortality, highlighting its value in early-stage HF management.

Dynamic assessment of left ventricular coupling and myocardial reserve in patients with cardiogenic shock

Aims

Pulmonary artery catheter haemodynamics are associated with improved survival in cardiogenic shock (CS). We investigated the utility of aortic pulsatility index (API) and cardiac power output (CPO) as surrogates for left ventricular (LV) coupling and myocardial reserve, respectively, in patients with CS undergoing dynamic assessment after a milrinone bolus.

Methods and results

Patients with SCAI Stage C CS underwent a milrinone drug study (50 mcg/kg bolus infused over 10 min) to assess inotropic response. Haemodynamic measurements were obtained at baseline and following the bolus. Aortic pulsatility index and CPO were used to risk-stratify patients with the incidence of LV assist device (LVAD), orthotopic heart transplantation (OHT), or death at 1 year as the primary composite endpoint. Two hundred and twenty-four patients in SCAI Stage C CS underwent haemodynamics prior to milrinone bolus, and 117 patients had low baseline API < 1.45. Of the 117 patients, 88 had a final API < 2.2 after milrinone load, consistent with LV decoupling, in which 73% met the composite endpoint. The remaining 29 patients had a final API ≥ 2.2 consistent with LV recoupling, and only 55% met the composite endpoint (P = 0.046). Of the 117 patients, 40 patients had low myocardial reserve (final CPO < 0.77 W), in which 78% met the composite endpoint. Of the 77 patients who demonstrated myocardial reserve (final CPO ≥ 0.77 W), only 64% met the composite endpoint (P = 0.039).

Conclusion

The use of API and CPO in a dynamic assessment after provocative testing led to improved risk stratification in patients with SCAI Stage C CS for clinical outcomes including LVAD, OHT, or death at 1 year.

Hemodynamic management of cardiogenic shock in the intensive care unit

Hemodynamic derangements are defining features of cardiogenic shock. Randomized clinical trials have examined the efficacy of various therapeutic interventions, from percutaneous coronary intervention to inotropes and mechanical circulatory support (MCS). However, hemodynamic management in cardiogenic shock has not been well-studied. This State-of-the-Art review will provide a framework for hemodynamic management in cardiogenic shock, including a description of the 4 therapeutic phases from initial 'Rescue' to 'Optimization', 'Stabilization' and 'de-Escalation or Exit therapy' (R-O-S-E), phenotyping and phenotype-guided tailoring of pharmacological and MCS support, to achieve hemodynamic and therapeutic goals. Finally, the premises that form the basis for clinical management and the hypotheses for randomized controlled trials will be discussed, with a view to the future direction of cardiogenic shock.

Improved Prognostic Performance of Right Atrial Pressure-Corrected Cardiac Power Output in Pulmonary Hypertension and Heart Failure with Preserved Ejection Fraction

Cardiac power output (CPO) is a powerful predictor of adverse outcomes in heart failure (HF). However, the original formula of CPO included the difference between mean arterial pressure and right atrial pressure (RAP). The prognostic performance of RAP-corrected CPO (CPORAP) remains unknown in heart failure with preserved ejection fraction (HFpEF). We studied 101 HF patients with a left ventricular ejection fraction > 40% who had pulmonary hypertension due to left heart disease. CPORAP was significantly more discriminating than CPO in predicting outcomes (Delong test, P = 0.004). Twenty-five (24.8%) patients presented with dis-concordantly high CPORAP and low CPO when stratified by the identified CPORAP threshold of 0.547 W and the accepted CPO threshold of 0.803 W. These patients had the lowest RAP, and their cumulative incidence was comparable with those with concordantly high CPO and CPORAP (P = 0.313). CPORAP might identify patients with right ventricular involvement, thereby providing better prognostic performance than CPO in HFpEF.

Standardization of the Right Heart Catheterization and the Emerging Role of Advanced Hemodynamics in Heart Failure

The accurate assessment of hemodynamics is paramount to providing timely and efficacious care for patients presenting in cardiogenic shock. Recently, the regular use of the pulmonary artery catheter in cardiogenic shock has had a resurgence with emerging data indicating improved survival in the modern era. Optimal multidisciplinary management of advanced heart failure and cardiogenic shock relies on our ability to effectively communicate and understand the complete hemodynamic assessment. Standardization of data acquisition and a renewed focus on the physiological processes, and thresholds driving disease progression, including the coupling ratio and myocardial reserve, are needed to fully understand and interpret the hemodynamic assessment. This State-of-the-Art review discusses best practices in the cardiac catheterization laboratory as well as emerging data on the prognostic role of emerging advanced hemodynamic parameters.

Variation in Hemodynamic Assessment and Interpretation: A Call to Standardize the Right Heart Catheterization

BACKGROUND

Invasive hemodynamic measurement via right heart catheterization has shown divergent data in its role in the treatment of patients with heart failure (HF) and cardiogenic shock. We hypothesized that variation in data acquisition technique and interpretation might contribute to these observations. We sought to assess differences in hemodynamic acquisition and interpretation by operator subspecialty as well as level of experience.

METHODS AND RESULTS

Individual-level responses to how physicians both collect and interpret hemodynamic data at the time of right heart catheterization was solicited via a survey distributed to international professional societies in HF and interventional cardiology. Data were stratified both by operator subspecialty (HF specialists or interventional cardiologists [IC]) and operator experience (early career [≤10 years from training] or late career [>10 years from training]) to determine variations in clinical practice. For the sensitivity analysis, we also look at differences in each subgroup. A total of 261 responses were received. There were 141 clinicians (52%) who self-identified as HF specialists, 99 (38%) identified as IC, and 20 (8%) identified as other. There were 142 early career providers (54%) and late career providers (119 [46%]). When recording hemodynamic values, there was considerable variation in practice patterns, regardless of subspecialty or level of experience for the majority of the intracardiac variables. There was no agreement or mild agreement among HF and IC as to when to record right atrial pressures or pulmonary capillary wedge pressures. HF cardiologists were more likely to routinely measure both Fick and thermodilution cardiac output compared with IC (51% vs 29%, P < .001), something mirrored in early career vs later career cardiologists.

CONCLUSIONS

Significant variation exists between the acquisition and interpretation of right heart catheterization measurements between HF and IC, as well as those early and late in their careers. With the growth of the heart team approach to management of patients in cardiogenic shock, standardization of both assessment and management practices is needed.

Prognostic value of right atrial pressure-corrected cardiac power index in cardiogenic shock

AIM

The pulmonary artery catheter (PAC)-derived cardiac power index (CPI) has been found of prognostic value in cardiogenic shock (CS) patients. The original CPI equation included the right atrial pressure (RAP), accounting for heart filling pressure as a determinant of systolic myocardial work, but this term was subsequently omitted. We hypothesized that the original CPI formula (CPI_RAP ) is superior to current CPI for risk stratification in CS.

METHODS AND RESULTS

A single-centre cohort of 80 consecutive Society for Cardiovascular Angiography and Interventions (SCAI) B-D CS patients with available PAC records was included. Overall in-hospital mortality was 21.3%. Results showed CPI_RAP to be the strongest haemodynamic predictor of in-hospital death (p_adj  = 0.038), outperforming CPI [area under the receiver operating characteristic (ROC) curves: 0.726 and 0.673, P-for-difference = 0.025]. When the population was stratified according to the identified CPI_RAP (0.28 W/m² ) and accepted CPI (0.32 W/m² ) thresholds, the cohort with discordant indexes (low CPI_RAP and high CPI) comprised a group of 13 patients featuring a congested phenotype with frequent right ventricle or biventricular involvement. In this group, in-hospital mortality was high (30.8%) similar to those with concordant low CPI and CPI_RAP .

CONCLUSION

Incorporating RAP in CPI calculation (CPI_RAP ) improves the prognostic yield in patients with CS SCAI B-D. A cut-off of 0.28 W/m² identifies patients at higher risk of in-hospital mortality. The improved prognostic value of CPI_RAP may derive from identification of patients with more intravascular congestion who may experience substantial in-hospital mortality, uncaptured by the commonly used CPI equation.