Table S1. Summary of adult studies on LV decompression in VA ECMO.
| Author | Decompression technique(s) | Year | Sample | VA-ECMO type | Diagnosis/indication for LV decompression | Results and learning points |
|---|---|---|---|---|---|---|
| Abu Saleh | Impella 5.0 | 2015 | 1 | Central | On POD5—increased CV and PA pressures, TEE showing LV dilatation with 10% EF | Successful LV unloading, bridged to Impella, weaned off all supports |
| Alhussein | Atrial balloon septostomy with transseptal needle | 2017 | 7 | Peripheral | TEE with LV dilatation and echo contrast ‘smoke’, ‘evidence of pulmonary edema despite medical therapy’ | Prior attempted medical therapy - inotropes, diuresis/dialysis. All initially improved with CXR. Procedural success 100%. 5/7 survived to hospital discharge, only 1 completely recovered biventricular function. A further 2 were transplanted, 1 received an LVAD, and 1 received a CentriMag VAD |
| Alkhouli | Transseptal LV cannula +/− balloon septostomy via femoral catheterisation |
2016 | 4 | Peripheral | Persistent pulmonary edema | Reduced PCWP and resolved pulmonary edema in all patients. 2/4 survived to discharge. Residual ASD underwent patch repair or monitored with plan for closure |
| Cheng | Impella 2.5 | 2013 | 5 | Peripheral | TEE with enlarged and dysfunctional LV with EF <20%; evidence of LV stasis with echo ‘smoke’; intermittent or absent opening of AV; PCWP >18 mmHg | Successful LV unloading in 4/5 patients and transition to long term LVAD. 1 death from progressive multiorgan failure. No major complications from Impella |
| Avalli | Percutaneous pulmonary artery cannulation, connected to venous ECMO limb. IABP later added | 2011 | 1 | Peripheral | Prior to ECMO institution—TEE showing large LV thrombus. LV venting done to prevent thromboembolism | Advantages of this approach include fewer complications compared to blade septostomy or transseptal stenting, less expensive than axial pump, and easier and faster to perform |
| Barbone | TEE-guided percutaneous transaortic LV pigtail catheter | 2011 | 3 | Peripheral | Inserted in catheterisation lab at the same time as ECMO initiation; evidence of LV dilatation and pre-ECMO LV thrombus reported in 1 patient | LV volume overload can be worsened in peripheral versus central ECMO |
| Bernhardt | TEE- and fluoroscopic-guided percutaneous transseptal TandemHeart cannula inserted into LA | 2017 | 1 | Peripheral | Preexisting LV thrombus and closed AV despite inotropes | Recovered and weaned without neurological sequelae, stably impaired LV and stable LV thrombus, nil ASD |
| Centofanti | Minimally invasive (thoracotomy) transapical LV vent and IABP | 2017 | 24 | Peripheral | To ‘relieve LV distention, pulmonary congestion, and avoid LV thrombosis’ | 15/24 patients survived to 30 days. Immediate haemodynamic improvement post transapical vent, shown by increased ECMO output, reduced CVP, increased MAP, and increased SvO2. 2/24 patients required surgical revision for chest wall bleeding from transapical cannula |
| Chocron | Percutaneous (via right subclavian artery) LV vent, connected to venous ECMO limb | 2013 | 1 | Peripheral | TEE with LV dilatation with grade 2 MV regurgitation | Weaned from ECMO but developed postanoxic coma and died 2 months later |
| Dahdouh | Percutaneous blade and balloon atrial septostomy | 2012 | 1 | Peripheral | Right heart catheterisation showing high LV filling pressures and stagnant contrast in pulmonary arteries | Immediately improved pulmonary edema and reduced LA pressures, improved ECMO output, survived to discharge |
| Dahdouh | Percutaneous blade and balloon atrial septostomy | 2013 | 1 | Peripheral | Right heart catheterisation showing high LV filling pressures and stagnant contrast in pulmonary arteries | Immediately improved pulmonary edema and reduced LA pressures, improved ECMO output, no neurologic sequelae and LVEF improved to 75% with non-significant residual shunt by discharge |
| Eliet | Impella 2.5 and 5.0 | 2018 | 11 | Peripheral | Severe LV overload with severe pulmonary edema, echo showing heavy spontaneous contrast in left heart, or loss of LV ejection (aortic velocity-time integral <5 cm, or pulse pressure <10 mmHg) including loss of AV opening | Proportional increases in pulmonary velocity-time integral and EtCO2, and decrease in LVEDD during Impella flow increase |
| Eudailey | Transdiaphragmatic LV vent (emergent incision made intraoperatively for manual cardiac massage post arrest) | 2015 | 1 | Peripheral | TEE showing LV distention, dysfunction, and stasis | TEE showing complete LV decompression, clinical improvement with decreased vasopressor requirements and normalisation of LVEF. Repaired diaphragm via patch cruroplasty |
| Guirgis | Minimally invasive (subxiphoid) apical LV vent | 2010 | 1 | Peripheral | Severe pulmonary edema, acutely elevated CVP, echo showing akinetic LV | Lack of proper equipment (e.g., specialised catheters, hybrid theatre) and trained staff precluded percutaneous decompression. Improvement of pulmonary edema post decompression, weaned to LVAD |
| Haynes | Percutaneous pulmonary venous puncture, with balloon-expandable stent placed across atrial septum under fluoroscopic and echo guidance |
2009 | 1 | Peripheral. Two venous cannulae in femoral and right internal jugular vein. | Haemorrhagic pulmonary edema, echo showing LV distention and spontaneous contrast in LA, low mixed venous saturation of 20% | Adults can have a thickened atrial septum, more difficult to penetrate and not suitable for pigtail catheters. Improved mixed venous saturations and reduced left heart size. Patient died 9 hours post decompression however (brain death), authors believe likely due to original arrest |
| Hong | TTE guided percutaneous transaortic catheter vent into LV. IABP inserted into 1 of 7 patients |
2016 | 7 | Peripheral | LV dysfunction with LVEF <25%, persistent pulmonary edema on CXR, or LV asystole on TTE | Nil procedural complications, 4/7 patients survived to discharge. Significant reduction in LVED and improved LVEF, and increased MAP in survivors |
| Hu | IABP | 2015 | 2 | Peripheral | LV dilatation, reduced LVEF, ventricular tachycardia | Improved LVEF and pulse pressure, nil recurrence of ventricular tachycardia, improved lactate. 1/2 patients survived |
| Jumean | Fluoroscopy-guided percutaneous transseptal TandemHeart cannula inserted into LA | 2015 | 1 | Peripheral | Preexisting LV thrombus, TEE showing LV distention, recurrent ventricular arrythmias | Reduced biventricular filling pressures, improved distention, resolution of refractory ventricular arrhythmias. Bridged to LVAD, but developed new right heart thrombus and died 2 weeks later from cardiogenic shock |
| Keenan | Minimally invasive (right minithoracotomy) LV vent, TEE-guided. One patient had preexisting IABP | 2016 | 3 | Peripheral | Severe pulmonary edema with LV dysfunction | Improved LV function and haemodynamics in one patient; 1/3 patients survived. Potential complications include mediastinitis and bleeding |
| Koeckert | Impella 2.5 | 2011 | 1 | Peripheral | Severe pulmonary edema and LV distention | Improved pulmonary edema on CXR and reduced LVEDD. Survived to discharge home |
| Lee | Percutaneous balloon atrial septostomy | 2017 | 1 | Peripheral | Worsening pulmonary edema and TTE showing LV distention | Improved pulmonary edema and LV distention; reduced cardiac enzymes. Survived to discharge |
| Lim | Impella CP | 2017 | 6 | Peripheral | NR | Reduced PAWP and PVR. 2/6 patients had complications from Impella - haemolysis, bleeding from insertion site |
| Lin | Fluoroscopic-guided percutaneous balloon atrial septostomy | 2017 | 15 | Peripheral | Refractory pulmonary edema | Failed transseptal puncture in 1/15 patients (kinking of device and cannula); repeat procedure required in 1/15 patients. 8/15 patients survived. Improved pulmonary edema on imaging |
| Litwinski | Fluoroscopic-guided percutaneous balloon atrial septostomy | 2017 | 1 | Central | Refractory pulmonary edema, echo showing distended and akinetic LV with lack of AV opening | Nil procedural complications. Improved ECMO output and resolution of pulmonary edema. Survived to discharge |
| Moazzami | Impella 2.5. 5/10 patients had prior IABP | 2017 | 10 | Peripheral (8/10), central (2/10) | NR | Immediate reduction in RA pressure and PCWP, decreased LVEDD. 5/10 survivors. 1/10 had fatal device malfunction and 1/10 had severe bleeding from Impella insertion site |
| Pappalardo | Impella 2.5 and CP. IABP use in a minority was adjusted for in propensity matching | 2017 | 157 (VA-ECMO and Impella, n= 34; VA-ECMO only, n=123) | Peripheral | Echo showing impaired LV unloading or stasis; 'impending' LV thrombosis, pulmonary edema, and/or significant aortic regurgitation | Greater rates of haemolysis and need for haemodialysis, and longer duration of VA-ECMO and ventilation in Impella and VA-ECMO group. Reduced mortality, higher rate of bridging to recovery or next therapy with Impella and VA-ECMO group |
| Peterss | Percutaneous Brockenbrough needle and balloon atrial septostomy | 2013 | 1 | Peripheral | LV dysfunction and refractory pulmonary edema | Immediate improvement in pulmonary edema on CXR, bridged to transplant and survived to discharge and at 6-month follow-up |
| Schmack | Right pulmonary vein puncture with cannula inserted into LV | 2017 | 48 | Peripheral (without LV vent, n=10), central (with LV vent, n=20; without, n=18) | NR, LV vent placed at same time as central ECMO | Improved 30-day survival in central ECMO with LV vent but nil difference in long term |
| Sidebotham | Percutaneous atrial septostomy (technique NS) | 2012 | 1 | Peripheral | Within 5 minutes of starting ECMO, TEE showing severe LV distention, loss of AV closure, and clinical evidence of pulmonary edema | Nil procedural complications. LV remained distended however with open AV and evidence of LV thrombus. Patient died |
| Tepper | Impella 2.5, 5.0, or CP (n=23), versus LV vent (n=22) placed through LV apex/right pulmonary vein/pulmonary artery | 2017 | 45 | Peripheral (n=18), central (n=27) |
NR. 1 patient had simultaneous ECMO and Impella placement, and 3 had preexisting Impella | CVP and LFTs significantly reduced in Impella, but not LV vent group. PADP significantly reduced post 48 h in both groups. Pulmonary edema on CXR improved in 13/20 surviving Impella patients, and 5/16 surviving vent patients. Similar 48 h survival and ICU discharge |
| Truby | Impella 2.5 and CP. IABP prior to VA-ECMO in 40% of patients | 2017 | 121 (19 decompressed) | Peripheral | Subclinical LVD: pulmonary edema on CXR and PADBP >25 mmHg within first 2 h of VA-ECMO; clinical LVD: requirement for immediate LV decompression due to pulmonary edema, refractory ventricular arrythmia, or significant stagnation of blood in LV | Reduced PADP, LVED in LVD patients. Similar survival. Lower rate of myocardial recovery and increased need for device transition in surviving LVD patients |
| Weymann | LV vent via right pulmonary vein | 2014 | 12 | Central | Elective | Overall survival to end of study 58.3% |
POD, postoperative day; CV, central venous; PA, pulmonary artery; TEE, transesophageal echocardiography; LV, left ventricle; CXR, chest X-ray; LVAD, left ventricular assist device; VAD, ventricular assist device; PCWP, pulmonary capillary wedge pressure; ASD, atrial septal defect; EF, ejection fraction; AV, aortic valve; ECMO, extracorporeal membrane oxygenation; IABP, intra-aortic balloon pump; SvO2, venous oxygen saturation; MV, mitral valve; LA, left atrium; LVEF, left ventricular ejection fraction; EtCO2, end tidal carbon dioxide; LVED, left ventricular end diastolic diameter; TTE, transthoracic echocardiography; NR, not reported; RA, right atrium; LFTs, liver function tests; PADP, pulmonary artery diastolic pressure; ICU, intensive care unit; LVD, left ventricular distention.