Cardiac power output index to define hemodynamic response to Impella support in cardiogenic shock

Cardiac power output ratio: Novel survival predictor after percutaneous ventricular assist device in cardiogenic shock

AIMS

Currently, there is limited data on prognostic indicators after insertion of percutaneous ventricular assist device (PVAD) in the treatment of cardiogenic shock (CS). This study evaluated the prognostic role of cardiac power output (CPO) ratio, defined as CPO at 24 h divided by early CPO (30 min to 2 h), in CS patients after PVAD.

METHODS AND RESULTS

Consecutive CS patients from the QEH-PVAD Registry were followed up for survival at 90 days after PVAD. Among 121 consecutive patients, 98 underwent right heart catheterization after PVAD, with CPO ratio available in 68 patients. The CPO ratio and 24-h CPO, but not the early CPO post PVAD, were significantly associated with 90-day survival, with corresponding area under curve in ROC analysis of 0.816, 0.740, and 0.469, respectively. In multivariate analysis, only the CPO ratio and lactate level at 24 h remained as independent survival predictors. The CPO ratio was not associated with age, sex, and body size. Patients with lower CPO ratio had significantly lower coronary perfusion pressure, worse right heart indices, and higher pulmonary vascular resistance. A lower CPO ratio was also significantly associated with mechanical ventilation and higher creatine kinase levels in myocardial infarction patients.

CONCLUSION

In post-PVAD patients, the CPO ratio outperformed the absolute CPO values and other haemodynamic metrics in predicting survival at 90 days. Such a proportional change of CPO over time, likely reflecting native heart function recovery, may help to guide management of CS patients post-PVAD.

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.

A novel 'shunt fraction' method to derive native cardiac output during liberation from central VA ECMO

The Fick principle is an established method to quantify intracardiac shunts. The Fick principle has also found utility in the practice of extracorporeal membrane oxygenation (ECMO). This report describes a novel 'shunt fraction' method to calculate intrinsic cardiac output in central (right atrial-to-aorta) ECMO. The physiological basis of this 'shunt fraction' method is described, followed by the case presentation that details the clinical application of this method of quantifying intrinsic cardiac output to guide weaning and liberation from central VA ECMO.

Clinical indications and outcomes of Impella devices for severe cardiogenic shock in COVID-19 patients: a systematic review

Background

Coronavirus disease 2019 (COVID-19) can present with significant cardiac dysfunction, including cardiogenic shock. Mechanical circulatory support with an Impella device may be utilized in these patients to support and offload native right ventricle (RV) and left ventricle (LV) functions. This systematic review aims to describe clinical indications, management, laboratory data, and outcomes in patients with severe cardiogenic shock from COVID-19 treated with an Impella device.

Methods

A PRISMA-directed systematic review was performed and prospectively registered in PROSPERO. The databases accessed included PubMed/MEDLINE, Scopus, and ScienceDirect. Quality and risk of bias assessments were completed using the Joanna Briggs Institute (JBI) checklist for case reports.

Results

A total of 16 records were included in the qualitative synthesis; 8/16 (50%) of the patients were men. The average age was 39 years (SD: 14.7). The biventricular Impella (BiPella) approach was recorded in 3/16 (18.75%) patients. A total of 4/16 (25%) individuals required renal replacement therapy (RRT). Single-device usage was observed in three cases: 2/16 Impella CP (12.5%) and 1/16 Impella RP (6.25%). Treatment of COVID-19 myocarditis included a wide range of antivirals and immunomodulators; 8/16 (50%) cases needed ECMO (extracorporeal membrane oxygenation) support. Overall, only 2/16 (11.7%) individuals died.

Conclusions

Sixteen reported individuals have received an Impella implanted with a mortality rate of 11.7%. Concurrent use of RRT and ECMO implantation was often observed. Overall, the Impella device is an effective and safe strategy in the management of COVID-19-related cardiogenic shock. Future studies should include long-term results.

Phenotyping and Hemodynamic Assessment in Cardiogenic Shock: From Physiology to Clinical Application

There is growing interest in invasive hemodynamic assessment in cardiogenic shock, primarily due to the widespread adoption of mechanical circulatory support (MCS). Invasive hemodynamic assessment is central to two aspects of cardiogenic shock management: (1) the phenotyping of cardiogenic shock, and (2) the assessment of response to therapy. Phenotyping of cardiogenic shock serves to guide timely therapeutic intervention, and the assessment of hemodynamic response to therapy directs the escalation or de-escalation of therapy, including MCS. This review aims to discuss these two aspects of hemodynamic assessment in cardiogenic shock. Firstly, the physiologic underpinnings of a phenotyping schema, and the implication of the cardiogenic shock phenotype on the MCS strategy in cardiogenic shock will be discussed. Secondly, the concept of cardiac power output and 'effective' oxygen delivery will be discussed in relation to hemodynamic response to therapy in cardiogenic shock.