German contribution to development and innovations in the management of acute myocardial infarction and cardiogenic shock

Impella versus extracorporal life support in cardiogenic shock: a propensity score adjusted analysis

Aims

The mortality in cardiogenic shock (CS) is high. The role of specific mechanical circulatory support (MCS) systems is unclear. We aimed to compare patients receiving Impella versus ECLS (extracorporal life support) with regard to baseline characteristics, feasibility, and outcomes in CS.

Methods and results

This is a retrospective cohort study including CS patients over 18 years with a complete follow‐up of the primary endpoint and available baseline lactate level, receiving haemodynamic support either by Impella 2.5 or ECLS from two European registries. The decision for device implementation was made at the discretion of the treating physician. The primary endpoint of this study was all‐cause mortality at 30 days. A propensity score for the use of Impella was calculated, and multivariable logistic regression was used to obtain adjusted odds ratios (aOR).

In total, 149 patients were included, receiving either Impella (n = 73) or ECLS (n = 76) for CS. The feasibility of device implantation was high (87%) and similar (aOR: 3.14; 95% CI: 0.18–56.50; P = 0.41) with both systems. The rates of vascular injuries (aOR: 0.95; 95% CI: 0.10–3.50; P = 0.56) and bleedings requiring transfusions (aOR: 0.44; 95% CI: 0.09–2.10; P = 0.29) were similar in ECLS patients and Impella patients. The use of Impella or ECLS was not associated with increased odds of mortality (aOR: 4.19; 95% CI: 0.53–33.25; P = 0.17), after correction for propensity score and baseline lactate level. Baseline lactate level was independently associated with increased odds of 30 day mortality (per mmol/L increase; OR: 1.29; 95% CI: 1.14–1.45; P < 0.001).

Conclusions

In CS patients, the adjusted mortality rates of both ECLS and Impella were high and similar. The baseline lactate level was a potent predictor of mortality and could play a role in patient selection for therapy in future studies. In patients with profound CS, the type of device is likely to be less important compared with other parameters including non‐cardiac and neurological factors.

Mechanical circulatory support with Impella versus intra-aortic balloon pump or medical treatment in cardiogenic shock-a critical appraisal of current data

AIMS

Patients suffering from cardiogenic shock (CS) have a high mortality and morbidity. The Impella percutaneous left-ventricular assist device (LVAD) decreases LV preload, increases cardiac output, and improves coronary blood flow. We aimed to review and meta-analyze available data comparing Impella versus intra-aortic pump (IABP) counterpulsation or medical treatment in CS due to acute myocardial infarction or post-cardiac arrest.

METHODS AND RESULTS

Study-level data were analyzed. Heterogeneity was assessed using the I² statistic. Risk rates were calculated and obtained using a random-effects model (DerSimonian and Laird). Four studies were found suitable for the final analysis, including 588 patients. Primary endpoint was short-term mortality (in-hospital or 30-day mortality). In a meta-analysis of four studies comparing Impella versus control, Impella was not associated with improved short-term mortality (in-hospital or 30-day mortality; RR 0.84; 95% CI 0.57-1.24; p = 0.38; I² 55%). Stroke risk was not increased (RR 1.00; 95% CI 0.36-2.81; p = 1.00; I²2 0%), but risk for major bleeding (RR 3.11 95% CI 1.50-6.44; p = 0.002; I² 0%) and peripheral ischemia complications (RR 2.58; 95% CI 1.24-5.34; p = 0.01; I² 0%) were increased in the Impella group.

CONCLUSION

In patients suffering from severe CS due to AMI, the use of Impella is not associated with improved short-time survival but with higher complications rates compared to IABP and medical treatment. Better patient selection avoiding Impella implantation in futile situations or in possible lower risk CS might be necessary to elucidate possible advantages of Impella in future studies.

Polyhedral erythrocytes in intracoronary thrombus and their association with reperfusion in myocardial infarction

OBJECTIVE

The tightly packed arrays of polyhedral erythrocytes, polyhedrocytes, formed during thrombus contraction, have been detected in some intracoronary thrombi (ICT) obtained from patients with ST-segment elevation myocardial infarction (STEMI). We sought to investigate determinants of polyhedrocyte content in ICT and its association with reperfusion in STEMI.

METHODS

We assessed the composition of ICT obtained during thrombectomy within 12 h since the symptom onset in 110 STEMI patients, following 300 mg of aspirin (n = 110) and 600 mg of clopidogrel (n = 75). The predominance of fibrin, erythrocytes, polyhedrocytes or platelets was evaluated using scanning electron microscopy.

RESULTS

Polyhedrocytes were found in 34 (30.9%) ICT, in which they covered 20-50% (median 38.8%) fields of view. Patients with polyhedrocytes in ICT had lower median minimal reference infarct-related artery (IRA) diameter by 20% (p < 0.0001) and area by 31% (p < 0.0001) versus those without polyhedrocytes. Time of ischemia showed association with the polyhedrocyte content (r = 0.26, p = 0.007). By multivariate analysis, minimal IRA diameter (β = - 0.50, p < 0.0001) and ischemia time (β = 0.20, p = 0.035) independently affected polyhedrocyte content in ICT (R² = 0.45, p < 0.0001). Patients with ischemia time of > 3 h and polyhedrocytes present in ICT had more frequently TIMI-2/3 flow after thrombus aspiration (96% vs. 67%, p = 0.02) and final TIMI-2/3 myocardial perfusion grade (92% vs. 57%, p = 0.044) versus those without polyhedrocytes.

CONCLUSIONS

Our findings indicate that the presence of polyhedrocytes in ICT, observed in one-third of STEMI patients, is associated with smaller minimal IRA diameter, prolonged ischemia and their formation in late presenters is associated with more effective thrombus aspiration and better myocardial reperfusion.