Intra-aortic balloon pump as a vent in VA-ECMO; lower risk, but beware

Abstract

I read with great interest the recent expert review in which the authors discussed left ventricular (LV) decompression strategies in patients supported by venoarterial extracorporeal membrane oxygenation (ECMO).1Welker CC Huang J Boswell MR et al.Left ventricular decompression in VA ECMO: Analysis of techniques and outcomes.J Cardiothorac Vasc Anesth. 2022; (Accessed date July 22, 2022, [e-pub ahead of print])https://doi.org/10.1053/j.jvca.2022.07.024Abstract Full Text Full Text PDF Scopus (3) Google Scholar Left ventricular decompression is essential for the prevention of increased LV pressure with ensuing stasis, left atrial distention, pulmonary edema, pulmonary hemorrhage, ventricular arrhythmias, and LV and aortic root clot formation.2Cevasco M Takayama H Ando M et al.Left ventricular distension and venting strategies for patients on venoarterial extracorporeal membrane oxygenation.J Thorac Dis. 2019; 11: 1676-1683Crossref PubMed Scopus (66) Google Scholar The LV venting strategies vary by institution, but usually begin with modification of ECMO flows, pharmacologic interventions on preload, contractility and afterload, and changes in positive end-expiratory pressure.3Lorusso R Shekar K MacLaren G et al.ELSO interim guidelines for venoarterial extracorporeal membrane oxygenation in adult cardiac patients.ASAIO J. 2021; 67: 827-844Crossref PubMed Scopus (52) Google Scholar If these methods are unsuccessful, other interventions may be necessary to avoid the complications of LV distention.3Lorusso R Shekar K MacLaren G et al.ELSO interim guidelines for venoarterial extracorporeal membrane oxygenation in adult cardiac patients.ASAIO J. 2021; 67: 827-844Crossref PubMed Scopus (52) Google Scholar Of particular interest and controversy as a venting strategy is the intra-aortic balloon pump (IABP). As stated by the authors, the IABP is placed through a small arteriotomy, is rapidly deployable, and has the added benefit of not being intraventricular.4Erdogan HB Goksedef D Erentug V et al.In which patients should sheathless IABP be used? An analysis of vascular complications in 1211 cases.J Cardiac Surgery. 2006; 21: 342-346Crossref PubMed Scopus (55) Google Scholar The IABP is a potentially ideal method of mechanical LV decompression in patients who have mechanical aortic valves or LV thrombus burden, situations in which Impella use is contraindicated.5Kaluski E Khan SU Sattur S et al.Impella CP dislodgment, swap, or removal: current practices.J Invasive Cardiol. 2019; 31: 36-40PubMed Google Scholar,6Santana JM Dalia AA Newton M et al.Mechanical circulatory support options in patients with aortic valve pathology.J Cardiothorac Vasc Anesth. 2022; 36: 3318-3326Abstract Full Text Full Text PDF PubMed Scopus (2) Google Scholar It is important to remember that some intrinsic LV function must be present for the IABP to provide support. This contrasts to transvalvular LV assist devices (ie, Impella), which do not require intrinsic myocardial function to decompress the LV. This is especially important in a patient supported by venoarterial-ECMO, because an IABP will give the appearance of pulsatility on an arterial pressure waveform regardless of whether the aortic valve is opening.7Donker DW Meuwese CL Braithwaite SA et al.Echocardiography in extracorporeal life support: a key player in procedural guidance, tailoring and monitoring.Perfusion. 2018; 33: 31-41Crossref PubMed Scopus (22) Google Scholar Thus, it is important to be vigilant for increases in pulmonary capillary wedge pressure, pulmonary edema, and ventricular arrhythmias as clues for insufficient venting. One method of quickly deciding if the aortic valve is opening is very briefly setting the IABP to standby and examining the arterial pressure waveform for pulsatility.7Donker DW Meuwese CL Braithwaite SA et al.Echocardiography in extracorporeal life support: a key player in procedural guidance, tailoring and monitoring.Perfusion. 2018; 33: 31-41Crossref PubMed Scopus (22) Google Scholar If the arterial pressure waveform is flat with the IABP on standby, and the patient is otherwise optimized, suspicion should be high for inadequate venting of the LV (or impending worsening LV failure), and echocardiographic assessment should be considered with the IABP active to assess for aortic valve opening, LV stasis, and aortic root thrombus. Importantly, if the aortic valve is only opening with IABP use, it may be wise to upgrade support to avoid further myocardial decompensation and subsequent LV stasis. None. Left Ventricular Decompression in VA-ECMO: Analysis of Techniques and OutcomesJournal of Cardiothoracic and Vascular AnesthesiaVol. 36Issue 11PreviewAFTERLOAD MISMATCHING during venoarterial extracorporeal membrane oxygenation (VA-ECMO) can result in left ventricular (LV) distention, which may increase patient mortality, morbidity, extracorporeal membrane oxygenation (ECMO) duration, and duration of mechanical ventilation. Less- invasive therapies to alleviate LV distention include decreasing ECMO flows, inotropes, vasodilators, diuretics, increasing positive end-expiratory pressure, improving venous drainage by repositioning cannulae, and placing an intra-aortic balloon pump (IABP). Full-Text PDF