- Mechanical circulatory support devices are mechanical pumps designed to assist or replace the function of the heart. The intra-aortic balloon pump (IABP) is the most widely used circulatory support device. - An IABP consists of a dual lumen catheter and console. It inflates during diastole to increase blood flow to the heart and deflates during systole to reduce workload on the heart. - Indications for IABP include cardiogenic shock, intractable angina, and as a bridge to recovery, transplant, or further therapy. Contraindications include aortic regurgitation and significant aortic disease. Complications can include limb ischemia, bleeding

1. Intra-Aortic Balloon
Pump &
Mechanical Circulatory
Support Devices
Dr. Suheil Dhanse

2. What we’re going to discuss here
▪ What are Mechanical Circulatory Support Devices?
▪ What is IABP?
– Indications
– Contraindications
– Placement
– Hemodynamic Effects
▪ What are some other circulatory support devices?
▪ Summary

3. ▪ Mechanical circulatory support (MCS) devices are
mechanical pumps
designed to assist or replace the function of
either the left or the right ventricle, or both ventricles, of the heart
Mechanical Circulatory Support Devices

4. 1. Location of the pumping chamber
2. Specific ventricle(s) supported
3. Pumping mechanism
4. Indicated duration of support
– Temporary (days to weeks)
– Long-term (months to years)
Important characteristics of MCS devices

6. Indications for MCS
▪ Bridge to recovery
▪ Bridge toTransplantation
▪ Destination therapy
▪ ?Bridge to Bridge

7. Indications for MCS
▪ Bridge to recovery
▪ Bridge toTransplantation
▪ Destination therapy
▪ ?Bridge to Bridge
▪ Bridge to recovery (BTR) refers to the use of MCS devices in
– patients with acute cardiogenic shock or ADHF
– that is refractory to optimal medical management (OMM)
– also there must be a reasonable expectation that the myocardial injury
is reversible and that myocardial function will recover during a short
period of temporary MCS
▪ Eg.;Acute MI, acute myocarditis, and postcardiotomy cardiogenic
shock
▪ Devices like
Intra-aortic balloon pumps (IABP)
surgically and percutaneously placed
extracorporeal/paracorporeal ventricular assist
devices (VADs)

13. Indications for MCS
▪ Bridge to recovery
▪ Bridge toTransplantation
▪ Destination therapy
▪ ?Bridge to Bridge
▪ Assumption that myocardial injury is reversible may not be
applicable in all clinical situations
▪ Temporary MCS may be started with expectation of
improvement only to realise that recovery is unlikely to occur
▪ Temporary MCS can be continued as a bridge to placement of
a long-term, implantableVAD (bridge to bridge [BTB]
application), or as a bridge to heart transplantation
▪ As a rule, patients should be excluded from consideration for
temporary MCS if myocardial recovery is unlikely and the option
of heart transplantation or implantation of a long-term, durable
VAD is not feasible.

14. Indications for MCS
▪ Bridge to recovery
▪ Bridge toTransplantation
▪ Destination therapy
▪ ?Bridge to Bridge
▪ Applies to patients in cardiogenic shock or DHF refractory to
OMM in whom recovery is unlikely (e.g., longstanding
ischemic, valvular, or idiopathic cardiomyopathy; severe AMI
or myocarditis)
and who are considered eligible for heart transplantation
▪ Durable, implantable MCS devices designed for long-term use
that permit untethered patient mobility and discharge from
the hospital are appropriate devices for this (BTT) indication
▪ Usually major procedure, including cardiopulmonary bypass is
required for placement in most patients
▪ Ideally are placed in patients with significant symptoms of
HF either on inotropes or who are not on inotropes but
have limiting symptoms at rest,
and in whom hemodynamics are stable and end-organ
function is preserved or slowly deteriorating

18. Indications for MCS
▪ Bridge to recovery
▪ Bridge toTransplantation
▪ Destination therapy
▪ ?Bridge to Bridge
▪ Refers to use of implantable MCS devices as a permanent
alternative to heart transplantation
▪ Used in chronic refractory symptoms of advanced HF that
result from irreversible forms of either non-ischemic or
ischemic cardiomyopathy and who are ineligible for heart
transplantation

19. IABP

20. Intra-Aortic Balloon Pump (Counter-
pulsation)
▪ Most widely used circulatory assist device
▪ IABP counter-pulsation system is composed of two principal parts:
– Dual lumen Flexible catheter
▪ 1 lumen allows for
either distal aspiration/flushing
or pressure monitoring
▪ Another lumen permits the periodic delivery and removal of helium gas to a closed
balloon (sizes between 20 and 50 cc)
– Mobile console that contains the system for helium transfer
as well as computer control of the inflation and deflation cycle
▪ HOMEWORK :Why is helium used for IABP and not other gases?

25. Technique of Placement
▪ Evaluation of the iliac and femoral arteries recommended to exclude significant
arterial disease
▪ Access in the common femoral artery is obtained via the Seldinger technique
▪ The balloon can be inserted through an 8- or a 9-Fr sheath or directly in a
sheathless fashion
▪ Before insertion, all the air in the balloon should be evacuated with a large syringe
attached to the one-way valve to maintain the lowest possible profile during
insertion
▪ Balloon catheter is advanced under fluoroscopic guidance over a stiff 0.021-inch
guidewire until the radiopaque tip marker reaches a level just distal to the left
subclavian artery
▪ After removal of the guidewire, the central lumen is flushed and connected to a
pressure transducer

26. Technique of Placement
▪ The balloon is then connected to the console, the system is purged with helium,
and counter-pulsation is started
▪ Proper placement and inflation of the balloon should be done fluoroscopically
▪ Timing of inflation and deflation should be optimized by either the surface
electrocardiogram (ECG) or the transduced pressure tracing to achieve optimal
hemodynamic support
▪ Newer IABP algorithms and software upgrades allow for auto-inflation and more
precise timing
▪ Vascular complications such as thromboembolism and stroke should be kept in
mind while considering the use of IABP
▪ Severe peripheral vascular disease or aortoiliac disease increases the risk of
vascular complications

28. Routine Care
▪ The following routine care measures likely decrease complication
rates
– A chest radiograph should be obtained after initial insertion and daily to
document the position of the catheter tip, which should be at the level of
bifurcation of left and right main bronchi
– Documentation of the distal pulses should occur before, after, and three times
every day
– Pressure wave form should be evaluated twice daily
– Daily measurement of the hematocrit, platelet count, and creatinine
– Anticoagulation. Fully effective heparin anticoagulation, monitored by activated
clotting time, during active IABP use
– Prompt assessment and troubleshooting in case of alarms

29. Counter-Pulsation
▪ Pumping is initiated and controlled by the console using input from
Aortic pressure AND/OR Electrocardiogram
▪ Trigger selection can be as desired or as appropriate
– Internal pressures (as detected by the catheter) for example during CPR
– ECG driven
▪ Augmentation can be as frequent as desired 1:1, 1:2, 1:3 etc
depending on the vendors available settings

30. Timing and Triggering
▪ IABP is often timed and triggered to the surface ECG
– Inflates at the end ofT wave
▪ corresponds to the dicrotic notch and beginning of diastole
– Deflates at the peak of R wave
▪ corresponds to the beginning of the isovolumic contraction
▪ The IABP can be triggered every QRS (1:1 inflation) or every other QRS (1:2, 1:3)
▪ Timing is adjusted to achieve the optimal waveform
▪ Best done under 1:2 or 1:3 pumping mode
– so that arterial tracings from consecutive beats with and without assistance can be compared
▪ Adjustment of timing is rarely necessary with the current generation of IABP
system
– these systems look at the tip pressure and automatically fine- tune the timing to achieve the
best arterial waveform

34. (A)The timing of balloon inflation is
adjusted until it occurs late in diastole,
uncovering the dicrotic notch.
Subsequently, inflation timing is moved
earlier in the cardiac cycle until the
dicrotic notch on the central aortic
tracing just disappears (beat #4).The
augmented pressure will rise as inflation
timing is moved earlier.
(B) Deflation knob is moved toward the
right (later in the cardiac cycle) until the
end diastolic dip is 10 to 15 mmHg below
the patient's unassisted diastolic
pressure.This will produce a maximal
lowering of the patient's unassisted
systolic pressure.
(C)The balloon console is triggering on
an atrial pacing artifact.This is corrected
by changing the console to a mode that
will discriminate between a pacing spike
and an R wave.

36. Hemodynamic Effects of IABP
▪ Inflation and deflation of the balloon has two major consequences:
– Blood is displaced to the proximal aorta by inflation during diastole.
– Aortic volume (and thus afterload) is reduced during systole through a vacuum
effect created by rapid balloon deflation.
▪ Effects may be quite variable and depend upon
– the volume of the balloon
– its position in the aorta
– heart rate, rhythm, the compliance of the aorta

37. Hemodynamic Effects of IABP
▪ Despite this variability, expected changes in the hemodynamic
profile in most patients with cardiogenic shock include
– 20% decrease in SBP
– 30% increase in DBP - may increase coronary blood flow to territory perfused by
a vessel with a critical stenosis
– Increase in MAP, especially in shock due to an acute mechanical abnormality
such as mitral regurgitation (MR) or ventricular septal defect (VSD) or to
improvement in perfusion of a territory resulting in overall improved ventricular
function
– Heart rate reduction by 20%
– 20% decrease in PCWP
– 2% elevation in the cardiac output

39. Indications for IABP
▪ Cardiogenic shock (left ventricular failure or mechanical complications of an
acute myocardial infarction)
▪ Intractable angina
▪ Low cardiac output after cardiopulmonary bypass
▪ Adjunctive therapy in high risk or complicated angioplasty
▪ Prophylaxis in patients with severe left main coronary arterial stenosis in
whom surgery is pending
▪ Intractable myocardial ischemia awaiting further therapy
▪ Refractory heart failure as a bridge to further therapy
▪ Intractable ventricular arrhythmias as a bridge to further therapy

40. Contraindications
▪ Significant aortic regurgitation since the degree of aortic
regurgitation will be increased
▪ Aortic dissection or clinically significant aortic aneurysm
▪ Uncontrolled sepsis
▪ Uncontrolled bleeding disorder
▪ Severe peripheral artery disease that cannot be pre-treated with
stenting

41. Duration of Use
▪ Generally used until benefits outweigh the risks
▪ Care of catheter is of utmost importance
– Regular flushing with heparinized saline
– If occluded arterial port, do not flush, remove and change
– Systemic anticoagulation if not contraindicated
▪ Remove as soon as patient stabilizes

42. Complications
▪ Factors associated with higher rate of complications
– Peripheral artery disease
– Older age
– Female sex
– Diabetes mellitus
– Hypertension
– Prolonged support
– Larger catheter size (>9.5 French)
– Body surface area <1.8 m2
– Cardiac index <2.2 L/min/m2

43. Complications
▪ Vascular Complications (6-25%)
– Limb (and visceral) ischemia
– Vascular laceration necessitating surgical repair
– Major haemorrhage
▪ Other
– Cerebrovascular accident is a rare complication of IABP
▪ If catheter placed too proximally
– Sepsis
– Balloon rupture
– Cholesterol embolisation

44. Thank You for Listening