Mechanical Therapies for Heart Failure

2020 Annual Chattanooga Cardiovascular SymposiumAlan Simeone, MD, FACS

Nothing to Disclose

What’s on the Agenda?

Acute Systolic Heart Failure

• Intra-aortic Balloon Pump

• Impella

• Extra Corporeal Membrane

Oxygenation (ECMO)

Chronic End-stage Systolic Heart Failure

• Key Concepts• Implantable Devices• Bridge vs Destination

• LV Failure • Implantable LVAD

• Bi-Ventricular Failure• Bi-VAD• Total Artificial Heart

Cardiogenic Shock

First Step is RecognitionArterial Access > Acid/Base, Lactate

Venous Access > PA Catheter

Additional Data

Cardiac Power Output

(MAP x CO)/451

Pulmonary Artery Pulsatility Index

(sPAP – dPAP )/CVP

Intra Aortic Balloon Pump

First used in 1967

Counterpulsation device most commonly inserted via femoral artery

7 to 9F catheter, 30, 40 or 50 cc Helium driven balloon

Inflates in Diastole, deflates prior to Systole

Timing by ECG or Arterial pressure tracing

Increases Diastolic Coronary Perfusion Pressure

Decreases LV Afterload

IABP Waveform

IABP

• Falling out of Favor in Cardiogenic Shock after Acute Myocardial Infarction

• Difficult to study – small numbers, many variables

• Newer percutaneous devices offer more quantifiable levels of support

• IABP remains very beneficial in the End-Stage chronic heart failure population

• Specifically, those failing on Inotropic support who are potential Transplant or Implantable Device Candidates

• Also useful as a temporary adjunct to medical therapy in Acutely Decompensated Chronic Heart Failure

• Remains useful in Post-Cardiotomy Shock

Impella

Miniature Axial Flow Pump mounted on a Catheter

Impella

• Impella 2.5• About 2.5 L/min, Femoral, 14F Sheath

• Impella CP• About 4 L/min, Femoral, 14F Sheath

• Impella 5.0• About 5 L/min, Cut-down, 23F Sheath

• Impella LD• About 5 L/min, Open Chest Asc. Aorta

• Impella 5.5• About 6 L/min, Cut-down, 23F Sheath

• Impella RP• About 4 L/min, Femoral VEIN, 23F Sheath

Impella Pros and Cons

• A True Mechanical Blood Pump

• Provides Forward Flow

• Can Decompress the LV• Reduces LVEDP

• - LA and Pulmonary Venous Pressure

• Reduce Wall Tension and O2 Demand

• Can Be a Percutaneous Option

• Expensive – Impella 2.5 20k to 23k

• Relatively large sheaths

• Malpositioning not unusual

• Hemolysis

• Short-term

• Good Evidence Still Sparse

Veno-Arterial Extra Corporeal Membrane OxygenationV-A ECMO

• Portable, Miniaturized Cardiopulmonary Bypass

• Venous Drainage Cannula

• Circuit Tubing

• Centrifugal Pump

• Oxygenator

• Arterial Return Cannula

V-A ECMOAdvantages

• Full Support of Perfusion – Flows depend on Cannula size assuming constant preload and afterload

• Support for Pulmonary Dysfunction

• Permits Recovery of Organ Function and Diuresis

• Hardware and Circuit can be inexpensive

• Can be instituted Quickly

Disadvantages• Bleeding

• Clotting

• Bleeding and Clotting

• Inflammatory Response

• Perfusion at the expense of LV Unloading

• Limb Malperfusion

• Limited Duration

• Personnel and Expertise required

• Exit Strategy essential

V-A ECMO

• Outcomes Depend on Patient Characteristics• Age

• Presence of Acute complications of Low Pressure/Low Flow

• Chronic Disease Burden

• Etiology and potential for recovery

• Downtime prior to initiation of support

• Suitability for more durable method of support

• An Excellent bridge to Durable Mechanical Support or Transplant in Patients with Decompensated End-Stage Heart Failure

How bad can living with end-

stage heart failure be?

It can’t be worse than a

VAD!Right?

Classification - Heart Failure

New York Heart Association (NYHA) Heart Failure Symptom Classification System

• I: No symptom limitation with ordinary physical activity

• II: Ordinary physical activity somewhat limited by dyspnea (e.g., long-distance walking, climbing two flights of stairs)

• III: Exercise limited by dyspnea with moderate workload (e.g., short-distance walking, climbing one flight of stairs)

• IV: Dyspnea at rest or with very little exertion

American College of Cardiology-American Heart Association Classification of Chronic Heart Failure

• A: High risk for developing heart failure: Hypertension, diabetes mellitus, CAD, family history of cardiomyopathy

• B: Asymptomatic heart failure: Previous MI, LV dysfunction, valvular heart disease

• C: Symptomatic heart failure: Structural heart disease, dyspnea and fatigue, impaired exercise tolerance

• D: Refractory end-stage heart failure: Marked symptoms at rest despite maximal medical therapy

550,000 Americans Hospitalized yearly despite best medical therapy

When Hospitalization Required

• 30 to 50% re-admitted within the first 6 months

One Year Mortality

Class II: 10 - 15%

Class III: 15 – 25%

Class IV: 30 – 50%

Inotrope-Dependent Advanced Heart Failure:

70 – 90% one-year mortality

• Transplant Effective but limited, prior to early 80’s was discarded

• Devices for Mechanical Support have existed since the early 1960’s

• Emphasis shifted from heart replacement to Ventricular Assistance• TAH has lingered – Current SynCardia TAH began life as the Jarvik-7

• Progress has seen transition from bulky, pulsatile mechanical pumps with complex moving parts to small, continuous-flow devices

• Compared to Medical Therapy, LVADs have significantly improved survival, Quality of Life and Functional Status since the landmark study in 2001.

Durable Mechanical Support Devices

HeartMate II HeartMate 3

• HeartMate II• Axial Flow

• Continuous Flow

• Mechanical Bearings

• Driveline

• External Battery Power

• Bridge to Transplant

• Destination Therapy

• HeartMate 3• Centrifugal Flow

• Continuous Flow, Pulsatility from algorithmic speed changes

• No Mechanical Bearings –Magnetically Levitated

• Modular Driveline

• External Battery Power

• Bridge to transplant

• Destination Therapy

• Two Year Survival 82%

• Any Stroke 9%

• Pump Thrombosis 1%

n engl j med 380;17 nejm.org April 25, 2019

LVAD - Not Perfect

• Require Anticoagulation• Bleeding

• Thrombosis

• Acquired von Willebrand’s syndrome

• Infection – Driveline is the Achilles Heel

• Aortic Regurgitation

• The Right Ventricle

Biventricular Failure

• Most Common Cause of RV Failure is LV Failure

• RV can usually recover with temporary medical and mechanical support• Centrimag RVAD

• Impella RP

Total Artificial Heart

• SynCardia TAH approved as a Bridge to Transplant

• A descendant of the Jarvik 7

• Pneumatically Driven, 4 valves• Intractable Arrhythmia

• Restrictive Cardiomyopathy

• ?Cardiac Tumor

• Mechanical Complication of MI

• Heart Failure in Adult Congenital

Biventricular Failure

• Magnitude of the problem dependent on potential for Transplant

• In a patient who is not a candidate for transplant >

• No good options for long-term support

• BiVAD implantable VADs have been used

• The RV VAD requires modification

The Future?

• Bivacor

• Investigational

• Centrifugal total artificial heart with a single magnetically levitated double-sided impeller

Thank You