Left heart Impella-device to bridge acute mitral regurgitation to MitraClip-procedure: a novel implementation of percutaneous mechanical circulatory support

Background

Acute mitral regurgitation (MR) is an emergency, often requiring urgent surgery. Severe acute MR presenting with hemodynamic collapse is usually caused by papillary muscle rupture or dysfunction after acute myocardial infarction (AMI) or chordal rupture, resulting in flail mitral leaflet(s). Preoperative stabilization is complex due to concomitant hemodynamic collapse and hypoxic respiratory failure. Finding the right balance between both preload and inotropic support is challenging. When patients are too sick for immediate surgical intervention, mechanical circulatory support can be considered because of its ability to both unload and reduce of cardiac work while increasing coronary perfusion and cardiac output. Nevertheless, even after initial stabilization, surgical risk remains high in critically ill acute severe MR patients and transcatheter treatments such as MitraClip are increasingly being explored.

Methods

Between August 2017 and September 2019, patients presenting with acute severe mitral regurgitation and considered too ill for immediate surgical intervention (EURO-II score >11.2% plus pulmonary oedema necessitating mechanical ventilation and/or hemodynamic instability), were selected for an Impella-assisted LV unloading technique as bridge to MitraClip-procedure. Five patients were selected for the combined left Impella/MitraClip-procedure in two tertiary cardiac ICUs.

Results

The mean age was 72 years. The cause of MR was ischemic in 20% and all patients presented in cardiogenic shock state, necessitating mechanical ventilation. The overall cardiac operative risk assessment (Euro-II) score predicted a 35% chance of in-hospital mortality. Cardiac output was severely impaired (mean LVOT VTI 8.2 cm). All patients were on inotropic support and supported by an Impella-CP pVAD (mean flow 2.5 Liter per minute; mean 6.3 days of support). In all cases, we managed to reduce the LVEDP below 15 mmHg using the combination of medical therapy (afterload reduction, inotropes), mechanical ventilation and pVAD-therapy. The MR was significantly reduced by a MitraClip-procedure in each Impella supported patient. The overall survival at discharge was 80%. One patient with late referral and multiple organ failure at presentation deceased due to refractory cardiogenic shock. Overall, severe MR was reduced to grade 1+ and all four patients survived 6 months after discharge with only one readmission for decompensated heart failure.

Conclusions

A combined strategy of Impella and MitraClip appears to be a novel, feasible alternative for patients presenting with acute, severe MR unable to proceed to a corrective surgical procedure at presentation due to severe left ventricular forward flow failure. In these cases, the early initiation of pVAD-support may reduce the risk of development of irreversible end- organ damage and dysfunction. Exploration in a larger, randomised population is warranted to investigate this strategy further.

Funding Acknowledgement

Type of funding source: None

P1716Dual antiplatelet therapy on veno arterial ECMO to bleed or not to bleed?

Background

Patients presenting with INTERMACS-1 cardiogenic shock and necessitating VA-ECMO, often undergo coronary angiography and percutaneous coronary intervention (PCI). Therefore, a substantial subset of VA-ECMO patients will have an indication for dual antiplatelet therapy (DAPT) plus unfractionated heparin (UFH). According to atrial fibrillation registry data, bleeding incidence on DAPT combined with oral anticoagulation is significantly higher as compared to anticoagulation alone. Although it has been reported that the addition of low dose aspirin to UFH did not increase bleeding or transfusion in VenoVenous (VV)-ECMO patients, it remains to be elucidated whether the addition of DAPT to UFH on VA-ECMO-therapy enhances bleeding.

Methods

We report single center data for 100 VA-ECMO patients between 2011 and 2019. VA-ECMO-patients post-surgery were excluded. Patient demographics, blood product transfusions and reported/radiographically diagnosed bleeding or thrombotic complications were analysed. All VA-ECMO patients received UFH, aiming for an anti-Xa levels of at least 0,3 U/ml. Targets were hemoglobin 7 g/dl, fibrinogen 100 mg/dl (or 150 mg/dl when active bleeding) and platelet counts above 50/fL. DAPT-patients were on a low dose aspirin plus a P2Y12-inhibitor (clopidogrel or ticagrelor).

Results

51% Of the VA-ECMO-group received DAPT (59% clopidogrel and 41% ticagrelor). UFH-levels were comparable between both groups. Patients on DAPT were significantly older (DAPT 52.8 vs. Control 41.3; p<0.001) and predominantly male (DAPT 76% vs. Control 63%). Total bleedings (DAPT 52% vs. Control 55%; p=0,68) and major bleedings (BARC score of 3 or more; DAPT 41% vs. Control 45%; p=0,71) did not differ significantly. We observed a significant lower number of clinically or radiographically overt arterial/venous thromboses (DAPT 13.7% vs. Control 36.2%; p=0,02) in the DAPT-group. When comparing fresh frozen plasma (FFP), red blood cell and platelet pool transfusions between both groups, only FFP-tranfusion (DAPT 0.47 units/day vs. Control 1.18 units/day; p=0,047) intends to be lower for the DAPT-group.

DAPT (plus UFH) vs control (plus UFH)

Conclusions

Haemorrhage is frequent during extracorporeal support. However, in our cohort, DAPT on top of UFH in the treatment of VA-ECMO-supported ischemic cardiogenic shock does not increase the risk of major bleeding. Therefore, DAPT should not necessarily be witheld in the setting of VA-ECMO. Interestingly, our data support a lower incidence of overt thromboses and a trend towards less FFP-transfusion. These findings suggest DAPT-induced platelet inhibition being protective against both thrombotic events and posibly consumptive coagulopathy without paying a price for major bleeding.

P1718Veno-arterial ECMO versus Left Impella bleeding complications in cardiogenic shock patients on dual antiplatelet therapy

Background

Selective groups of patients, presenting with INTERMACS-1 cardiogenic shock due to acute ischaemic heart failure, may benefit from mechanical circulatory support (MCS). Patients with biventricular failure, severe septic shock or oxygenation problems should be selected for VA-ECMO, although the left Impella-CP heart pump can be considered as a less invasive alternative in supporting predominantly left ventricular failure. Bleeding issues are a major concern in patients on MCS, especially in this group where triple anticoagulation therapy (unfractionated heparin (UFH) for prevention of pump thrombosis and dual antiplatelet therapy (DAPT) after coronary stenting) is necessitated. We aim to investigate the bleeding and transfusion rate in DAPT-patients on VA-ECMO versus Impella.

Methods

We report single center data for 51 VA-ECMO and 8 Impella patients between 2011 and 2019. Indication for MCS was acute ischaemic cardiogenic shock. Patient demographics, transfusions and reported/radiographically diagnosed bleeding (BARC-classification) complications were analyzed. All patients received UFH and low dose aspirin plus clopidogrel or ticagrelor. Impella flow was at least 2.5 L/min. Transfusion targets were Hb >7 g/dl, fibrinogen >100 mg/dl (or >150 mg/dl when active bleeding) and platelet count >50/fL.

Results

Impella patients were significantly older (VA-ECMO 52.8 vs. Impella 62.4; p=0.02) as compared to the VA-ECMO group. Anti-Xa-levels and length of the MCS-run (mean 7.9 VA-ECMO vs. 6.4 days Impella) were comparable in both groups. Occurrences of minor bleeds was comparable between both groups (mainly oozing from the insertion site in the ImpellaTM group 63% vs. VA-ECMO 72%; p>0.05) but major bleedings with BARC score of 3 or more were significantly lower in the Impella group (13% vs. VA-ECMO 65%; p=0.005). Platelet and red blood cell transfusions were significantly lower in the Impella group (0.1 units of platelets per day vs. 1.1 units of platelets per day on VA-ECMO; p=0.002 and 0.8 units of RBCs per day vs. 2.6 units of RBCs per day on VA-ECMO; p=0.02).

Bleeding/transfusion VA-ECMO vs Impella

Conclusions

Bleeding is a frequent complication of MCS. However, in our cohort, triple anticoagulation in acute cardiogenic shock due to ischaemic left ventricle failure resulted in a lower major bleeding rate when support was given by the left Impella device as compared with VA-ECMO therapy group. As a result, platelet and red blood cell transfusions were lower in the Impella group. These findings are likely to be partly explained by the increased number and size of cannulas in VA-ECMO, as well as the increased risk of haemolysis and consumptive coagulopathy due to the complexity and extensive foreign body surface of the ECMO-circuit. We conclude that Impella support should be considered as a safer option than VA-ECMO with regards to bleeding in patients with ischaemic left ventricular failure who require DAPT and MCS as a bridge to recovery or other definitive therapy.

Diagnosis of death using neurological criteria in adult patients on extracorporeal membrane oxygenation: Development of UK guidance

The diagnosis of death using neurological criteria is an important legal method of establishing death in the UK. The safety of the diagnosis lies in the exclusion of conditions which may mask the diagnosis and the testing of the fundamental reflexes of the brainstem including the apnoea reflex. Extracorporeal membrane oxygenation for cardiac or respiratory support can impact upon these tests, both through drug sequestration in the circuit and also through the ability to undertake the apnoea test. Until recently, there has been no nationally accepted guidance regarding the conduct of the tests to undertake the diagnosis of death using neurological criteria for a patient on extracorporeal membrane oxygenation. This article considers both the background to and the process of guideline development.

Leptospirosis presenting as severe cardiogenic shock: A case report

Background

Leptospirosis is a rare infectious illness caused by the Spirochaete Leptospira. It has a wide-varying spectrum of presentation. We present a rare case of severe cardiogenic shock secondary to leptospirosis, in the absence of its common clinical features.

Case presentation

A 36-year-old woman presented to our unit with severe cardiogenic shock and subsequent multi-organ failure. Her clinical course was characterised by ongoing pyrexia of unknown origin with concurrent cardiac failure. She was initially managed with broad-spectrum antibiotics and inotropes. Percutaneous cardiac biopsy excluded major causes of myocarditis. On day 21 after presentation, she was found to be IgM-positive for leptospirosis.

Conclusions

This is a rare case of severe cardiogenic shock secondary to leptospirosis infection. The case also highlights the importance of obtaining a thorough social history when assessing a patient with an unusual presentation, as clues can often be missed.