Table 6.7. Recommendation for left ventricular venting in patients receiving extracorporeal membrane oxygenation (ECMO).

Recommendations	Class	LE	Comments	Table 2018	Ref.
Consider strategies for left ventricular venting in patients receiving mechanical circulatory support via peripheral venoarterial ECMO, evidence of ventricular distension associated with severe hypocontractility and pulmonary congestion.	IIa	C	NEW: The current recommendation reflects data from observational studies and meta-analyses.	New	69–73
The use of peripheral venoarterial extracorporeal membrane oxygenation (ECMO) is characterized by an increase in LV afterload caused by blood flow from the arterial return cannula, which can worsen cardiac hypocontractility, causing ventricular distension and pulmonary congestion. In many cases, the reduction in ECMO flow combined with inotropic therapy may be sufficient to decompress the LV.74 However, in refractory cases, other methods of venting may be used, including atrial septostomy; surgical implantation of a transapical catheter; percutaneous pulmonary artery venting through the jugular vein; and mechanical circulatory support device (MCSD), such as the intra-aortic balloon pump (IABP), Impella®, or CentriMag®. In observational studies, LV venting has been associated with reduced mortality, increased myocardial recovery, and shorter weaning time from ECMO in patients with CS treated with peripheral venoarterial ECMO.69–72 Each venting technique presents inherent risks that must be considered individually according to the etiology of the underlying disease, limitations of the access site, presence of coagulopathies, availability of MCSDs and experience of each center.75 Despite known limitations, IABPs remain the most commonly used devices, with a recent meta-analysis suggesting lower risk of complications such as stroke, peripheral ischemia, and hemolysis from decompression by IABP as compared to other methods, at the cost of increased bleeding.73 However, no randomized clinical trial has been conducted to date to establish the ideal LV venting method, and prospective studies are needed. There is also no consensus on whether LV venting should be performed preventively or as a rescue measure. Known indications for LV venting include elevated PCWP, distended and hypocontractile LV, LV with echocardiographic evidence of blood stasis, decreased aortic valve opening during the cardiac cycle, hypoxemia, progressive pulmonary edema, and refractory ventricular arrhythmia.

CS: cardiogenic shock; ECMO: extracorporeal membrane oxygenation; LV: left ventricle; MCSD: mechanical circulatory support device; PCWP: pulmonary capillary wedge pressure.