Ventricular assist devices (VADs) are mechanical pumps that help the failing heart pump blood. There are two main types - pulsatile VADs that pump blood in pulses and continuous flow VADs that pump blood continuously. VADs are used as a bridge to heart transplant, to help the heart recover, or as destination therapy for those not eligible for transplant. They are implanted using cardiopulmonary bypass to connect the inflow cannula in the left ventricle to the outflow cannula in the aorta. VADs improve heart function and quality of life for patients with heart failure.

1. Ventricular Assist Devices
Dr.Elamaran.E
Senior Resident
Dept. of CTVS

2. Mechanical circulatory
support (MCS) is a means
of imparting energy for
forward flow of blood in
the body by manmade
devices.

3. History

4. 0 In the presence of prolonged cardiac unloading with
an LVAD, myocyte size and myocardial collagen
content and collagen production (fibrosis) generally
decline.
0 On an anatomic and functional level, chronic LVAD
support generally results in reduction in left
ventricular mass as well as left ventricular end-
systolic and end-diastolic volume - improvement in
left ventricular ejection fraction

5. Indications
Duration of use
0 Bridge to recovery
Postcardiotomy cardiogenic shock.
Post acute-myocardial infarction (MI) cardiogenic shock.
Myocarditis-induced cardiogenic shock
Support during medical or ablative therapy for
intractable dysrhythmias.
0 Bridge to Transplant
0 Bridge to Destination Therapy

7. Indications
1. NYHA functional class IV symptoms
2. Life expectancy < 2 years
3. Not a candidate for heart transplantation
4. Failure to respond to optimal medical management for at
least 60 of the last 90 days
5. Left ventricular ejection fraction 25%
6. Refractory cardiogenic shock or cardiac failure
7. Continued need for intravenous inotropic therapy limited by
symptomatic hypotension, decreasing renal function, or
worsening pulmonary congestion
8. Body surface area > 1.5 m2
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8. Contraindications
0 Age > 65 years, unless minimal or no other clinical risk factors
0 Chronic kidney disease with serum creatinine level 3.0 mg/dL
0 Severe chronic malnutrition (BMI < 21 kg/m2 in males and
< 19 kg/m2 in females)
0 Morbid obesity (BMI 40 kg/m2)
0 Mechanical ventilation
0 Recent or evolving stroke
0 Neurological deficits impairing the ability to manage device
0 Coexisting terminal condition (eg, metastatic cancer, cirrhosis)
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9. 0 Abdominal aortic aneurysm > 5 cm
0 Biventricular failure in patients older than 65 years
0 Active systemic infection or major chronic risk for infection
0 Fixed pulmonary or portal hypertension
0 Severe pulmonary dysfunction (eg, FEV1 < 1 L)
0 Impending renal or hepatic failure
0 Multisystem organ failure
0 Heparin-induced thrombocytopenia
0 Significant underlying psychiatric illness or lack of social support
that may impair ability to maintain and operate VAD
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10. Design of Ventricular Assist Device
Basic Components of VAD
1. Blood pump
2. Controller
3. Power source
4.Inflow cannula
5.Outflow cannula

11. Krishnamani, R. et al. (2010) Emerging ventricular assist devices for long-
term cardiac support
Nat. Rev. Cardiol. doi:10.1038/nrcardio.2009.222

12. Pulsatile VAD

13. Continuous flow VAD

16. Technique of Insertion
0 Pulmonary artery catheter
0 Intraoperative TEE
 assessment of biventricular function
evaluation of aortic insufficiency
presence of a patent foramen ovale
identification of intracardiac and aortic air bubbles
during implantation and subsequent de-airing
maneuvers
assessment of inflow cannula position within the left
ventricle.

17. 0 Device pocket creation
0 CPB established
0 Heart is maintained in a continuously beating state
without cardioplegic arrest
0 Left ventricular apex is displaced, and an opening is
created in the left ventricle for insertion of the apical
cannula
0 Deairing of the device

18. 0 End-to-side anastomosis is then constructed to the
right lateral aspect of the ascending aorta
0 Drive line is brought out through a long subcutaneous
tunnel and passed off the surgical field and connected
to the pump console
0 Full pumping is established, and CPB is discontinued
with continued surveillance by TEE for air and right
ventricular function