5- Treatment of end-stage heart failure with mechanical circulatory support.

define end stage chronic HF

• NYHA IV- unable to carry out any physical activity without discomfort + symptoms at rest

• due to ischemic DCM, HCM, congenital heart disease

what is mechanical circulatory support

• any device that contributes to the pump function of the heart

what are the different strategies for short term support

• bridge to recovery

  • support heart until it recovers to function on its own

  • eg AMI, myocarditis, post cartiotomy syn, primary graft failure

• bridge to decision or bridge to bridge

  • support while deciding long term plan

  • temporary device to upgrade to a more durable one

  • eg cardiogenic shock, imminent multiorgan failure

what are the short term mechnical supports

• intraaortic balloon pump

• ECMO

• Levitronix centrimag

what are the basic mechanisms of intra aortic balloon pumping

• placed in thoracic aorta balloon inflated during diastole

  • increasing aortic pressure during diastole and incrasing coronary blood flow

• balloon deflated prior to and during early left ventricular ejection

  • reduces aortic pressure + afterload

what are the indications of intra aortic balloon pumping

• bridge therapy in conditions with reduced CO → prevents cardiogenic shock

• unstable coronary state

• pump failure

• acute mitral regurgitation

what are the beneficial effects of intra aortic balloon pumping

• reduces cardiac work by decreasing afterload

• increases coronary blood flow

• cheap and easily accessible

what are the disadvantages of intraaortic balloon pumps

• not reducing volume overload of LV

• risk of critical limb ischemia

• full anticoagulation is needed

what is the ECMO

• heart lung machine that can be used outside the OR

• suck blood out of bore canula that is in the IVC → oxygenator + pump → gas exchange → arterialises blood → back to patient with another canula in femoral artery

• fix perfusion first

what are the advantages of ECMO

• easy insertion

• feasible for patient transport

• full circulatory support and oxygenation

• peripheral canullation

  • femoral a, v

what are the disadvantages of ECMO

• short term support max 1 week

• limited lifetime of membrane

• need for thermoregulation

• possible limb ischemia

  • distal canulla should be considered

what are the complications of ECMO

• coagulation disorders vWF, bleeding

• haemolysis, thrombocytopenia

• thromboembolic events

• infection/ sepsis

what is the difference between VA and VV ECMO

• Venous- arterial

  • suck out of femoral vein → oxygenate → descending aorta

• Venous-venous

  • blood sucked out → into venous system

what is Levitronix centrimag

• similar to ECMO- but no gas excahnge

• implanted surgically to the large arteries or atria → supprots left and right heard

what is the use of Levitronix centrimag

• BIVAD therapy- for 1-2 months until they are fit enough to be disconnected or heart transplant

what are the long term strategies for long term support

• bridge to transplant or bridge to candidacy

  • most frequent due to long waiting lists

• destination therapy

  • pts inelegible for heart Tx, support the heart long term

what are the long term mechanical supports

• Berlin Heart EXCOR

• Heart Mate 2

• HeartMate 3

what is BerlinHeartEXCOR

• pneumatic, pulsatile flow pump

• long term full cardiac support

• high thombotic and bleeding risk

  • strong anticoagulation is needed because of large surface and mechanical valves

• LVAD, RVAD, BIVAD setting is available

• can use for kids

what is the Abbott HeartMate 3

• 2rd gen continuous flow centrifugal pump

• only left ventricular support

• 5-10l/min pump flow

• optimal bleeding and thrombotic profile

• long term therapy possible

• patients can be discharged home

what does the patient have to do at home with the Abbott HeartMate 3

• Charging and changing of batteries

• Aseptic treatment of driveline exit site

• Immobilisation of percutaneous cable

• Daily cleaning activities (shower bag)

• Anticoagulation - Accucheck INR

• Patient diary: body weight, INR OAC

• dose, temperature, device parameters

• Regular follow up monthly

what are the complications of LVADs

• GI bleeding
• RV failure
• driveline infection
• sepsis
• bleeding
• pump pocket infection
• intracranial haemorrhage

what is observable during examination in patients with LVADs

• no palpable peripherial pulse
• false data during pulsoximetry
• BP measurement is problematic
• doppler pressure measurement is problematic
• doppler method recommended

what should you check for during physical exam in LVADs

• look for signs of good perdusion
  • adequate capillary filling
  • lack of cianosis or HF symtpoms
  • condciousness

how do you check if the LVAD is functioning

• easy with stethoscope- buzzing sound over the left side of chest
• pump stop is a catastrophic condition → cardiogenic shock, deat