What is intra-aortic balloon pump? | Balloon that controls coronary artery perfusion in case of heart failure, inflates to stop flow and deflates to continue
Effects: lower LV afterload, enhances coronary perfusion during diastole.
Indications: acute coronary syndrome, unstable angina, early stage heart failure
CI: severe aortic valvular insufficiency, aortic dissection |
What is extra-corporeal membrane oxygenation? | Modification of heart-lung machine, ECMO for respiratory failure, ECLS for heart failure.
Drains venous blood, parallel circulation [mechanical pump] gas exchange in oxygenator, blood returns into artery/vein
Indication: Acute ischemic HF, acute HF after open heart surgery, acute or chronic graft failure after heart transplant, pulmonary embolism, acute viral myocarditis w/HF, intoxication, hypothermia, drowning
Requirements: pump, console, disposables, tubes, canulae [arterial and venous]
Can be central or peripheral (femoral arteries and veins) circulatory support |
How are peripheral implantations of ECMO? | • Quick installation.
• Using femoral vessels (at the groin).
• Takes 30 minutes from start until bypass instauration.
• Possible during CP resuscitation
• Impaired limb perfusion (reperfusing canula).
• Lung edema if absent cardiac flow (up to 20%).
• Low cerebral O2 saturation if persistent cardiac flow (competitive flow between the heart and the machine pump) |
What are cons of peripheral implantation of ECMO? | • Lung edema if absent cardiac flow (up to 20%).
• Low cerebral O2 saturation if persistent cardiac flow (competitive flow between the heart and the machine pump) |
How are central implantations of ECMO? | • Adequate cerebral oxygenation.
• Prevents lung edema (placing a left atrial Vent connected to venous canula)
• More invasive (usually used after a fresh sternotomy). |
What are considerations to institute ECMO therapy? | • Likelihood of organ recovery: appropriate if disease process is reversible with therapy and rest on ECMO.
• Cardiac recovery: to either wait for
- cardiac recovery (bridge to recovery)
- implanting a longer-lasting device (LVAD: bridge to therapy)
- transplantation (bridge to transplantation)
• Disseminated malignancy.
• Advanced age.
• Graft vs. host disease.
• Known severe brain injury.
• Unwitnessed cardiac arrest or cardiac arrest of prolonged duration. |
What are CI of ECMO? | • Aortic valve regurgitation or aortic dissections.
• Useless in ruptured aortic dissections.
• DIC.
• Thrombolysis |
What are ECMO complications? | • Limb ischemia.
• Embolic events (clots, air).
• Consumption of coagulating factors.
• Hemorrhage (cerebral)
Impossinle Weaning: Heart
• Heart transplantation.
• Ventricular Assistance Devices (VAD): Bridge to transplantation.Destination therapy if transplantation is contra-indicated.
• Death |
What is indication for respiratory support ECMO? | • Acute onset of ARDS (bird flu).
• Single lung pneumonia (after a surgical pneumonectomy).
• Acute or chronic graft failure after lung transplantations
Veno-venous connection (dual cannulae or single cannulae)
New insights: percutaneous RB shortcut
Impossible weaning: Lung
Lung transplant/death |
What is LVAD? | External pneumatic ventricle, Axial pump (percutaneous), Centrifugal pump, axial mini-pump, post-auricular connector, future is 15 mm Jarvik/wireless |
What is RVAD? | Indications: • In chronic diseases, RVAD is exceptional if
isolated, usually combined to LVAD or during a TAH.
• Mainly in acute right ventricular failure.
- Acute phase after a cardiac surgery.
- Acute Pulmonary Hypertension (ARDS, Cor pulmonale, etc…
Principles: • Use an LVAD device and implant it on the right side.
• No true apex of the RV, the inlet has to be implanted in the RA with the exit vascular graft connected to the PA.
New Insight: percutaneous RV shortcut/ with RV venting |
What is BiVAD? | External pneumatic ventricles, Total artificial heart “Biological” Total artificial heart, |
Conclusion of ECMO, IABP, VAD? | • IABP is efficient for the treatment of angina, and to a lesser extent for heart failure.
• ECMO is the treatment of choice in acute severe heart failure.
• LVAD is mainly used as a bridge to transplantation or as a destination therapy
• BiVAD should be used whenever there is a biventricular heart failure mainly as a bridge to transplantation or as a destination therapy.
• Newly totally artificial hearts are expected to have a longer survival period and lower incidence of complications. It is hoped to replace heart transplantations |