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Megan Shifrin, RN, MSN, ACNP-BC Vanderbilt University. Advanced Heart Failure and the Role of Mechanical Circulatory Support. Objectives. Review current recommendations for advanced heart failure management Identify the different types of VADs currently in use
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Megan Shifrin, RN, MSN, ACNP-BC Vanderbilt University Advanced Heart Failure and the Role of Mechanical Circulatory Support
Objectives • Review current recommendations for advanced heart failure management • Identify the different types of VADs currently in use • Identify the indications and contraindications for placement • Overview of immediate post-operative management and potential complications
Why Should I Care About Heart Failure or LVADs? • Prevalence – According to the American Heart Association, there are close to 6 million Americans living with heart failure. • Incidence – Almost 550,000 new cases are diagnosed annually. • About 300,000 people die each year of heart-failure related causes. • Heart failure is the single most common cause of hospitalization in the United States for people over the age of 65. • In 2012 alone, there were 2,066 permanent LVADs placed in patients. • These patients live in your community.
The Cost of Heart Failure Management in the United States Total Cost $39.2 billion Hospitalization$20.9 53.3% Nursing Home$4.7 11.9% 6.4% 10.5% Physicians/Other Professionals$2.5 8.2% Lost Productivity/Mortality* $4.1 9.7% Drugs/Other Medical Durables$3.2 Home Healthcare$3.8 Heart Disease and Stroke Statistics—2010 Update: A Report From the AHA Circulation, Feb 2010; 121: e46 - e215
Etiologies of Heart Failure Ischemic cardiomyopathy • Hypertension • Coronary artery disease • Myocardial infarction • Non-ischemic cardiomyopathy • Valvular disease • Viral/bacterial cardiomyopathy • Peripartum cardiomyopathy • Idiopathic/familial cardiomyopathy • Myocarditis • Connective tissue disorders • Drugs/Toxins • Alcohol
New York Heart Association Functional Classification of Heart Failure Increasing Severity Class I Class II Class IIIa and IIIb Class IV • Mild symptoms (mild shortness of breath and/or angina) • Slight limitation during ordinary activity • Cardiac disease • No symptoms • No limitation in ordinary physical activity • Marked limitation in activity due to symptoms • Comfortable only at rest • Severe limitations • Symptoms even while at rest • Mostly bedbound patients
Goals of Heart Failure Management • Improving symptoms and quality of life 2. Slowing the progression or reversing cardiac and peripheral dysfunction 3. Reducing mortality
Addressing Heart Failure in 2013 Katz AM Heart Failure
Evidence of Progressing Heart Failure • Decreased end organ perfusion • Renal function • Liver function • Pulmonary function We need more support!
Ventricular Assist Device (VAD) A mechanical circulatory device used to partially or completely replace the function of either the left ventricle (LVAD); the right ventricle (RVAD); or both ventricles (BiVAD) Long-Term LVAD Implanted surgically with the intention of support for months to years Short-Term LVAD Utilized for urgent/ emergent support over the course of days to weeks
Things to Consider Before Placing ANY type of VAD Support • Are there any contraindications to VAD support? • End-stage lung, liver, or renal disease • Metastatic disease • Medical non-adherence or active drug addiction • Active infectious disease • Inability to tolerate systemic anticoagulation (recent CVA, GI bleed, etc.,) • Moderate to severe RV dysfunction for some LVADs • What are our other issues in this particular patient? • What are the patient’s goals? What are our goals? • What happens if we don’t meet our goals?
INTERMACS SCORE Interagency Registry for Mechanically Assisted Circulatory Support Long-Term LVAD Ideal candidates are INTERMACS classes 3-4 Short-Term LVAD Candidates are INTERMACS classes 1-2 Not a LVAD Candidate INTERMACS 1 or those with multisystem organ failure Lietz and Miller CurrOpinCardiol 2009, 24:246–251
Destination Therapy vs. Bridge to Transplantation Long-term placement • Destination Therapy (DT) • Not a heart transplant candidate • NYHA IV • LVEF <25% • Maximized medical therapy >45 of 60 days; IABP for 7 days • Functional limitation with a peak oxygen consumption of less than or equal to 14 ml/kg/min • Life expectancy < 2 years • Bridge to Transplantation (BTT) • Patient is approved and currently listed for transplant • NYHA IV • Failed maximized medical therapy http://www.cms.gov/medicare-coverage-database
Adult FDA Approved LVADs Destination Therapy (DT) HeartMate II (Thoratec) Bridge to Transplantation (BTT) HeartMate II (Thoratec) HeartWare (HeartWare) PVAD (Thoratec) IVAD (Thoratec)
Basics of HM II Pump Speed (RPM) – How quickly the pump rotates Pump Power (Watts) – Measure of motor voltage and current Pump Flow (L/min) - Estimated value of the volume running through the pump Pulsitility Index – The measure of the left ventricular pressure during systole
Management Considerations • Typically pulseless • Afterload sensitive • Preload sensitive • Anticoagulation • Should not receive chest compressions during an arrest • Patients still have heart failure
Potential Device Complications Outflow graft (kink , leak) Inflow cannula (poor position, obstruction) Drive line infection / fracture Pump/rotor dysfunction (thrombus) Controller malfunction Battery dysfunction
Hematologic Long-Term Complications • GI bleed • 13-40% of LVAD patients • Constitute 9.8% of LVAD readmissions • CVA (embolic and hemorrhagic) • 17% of patients who survived 24 months post-implant • Hemolysis • Increases rate of mortality by 25% over six months
“However beautiful the strategy, you should occasionally look at the results.” Winston Churchill
Medical Management vs. LVAD Rose, EA; et al NEJM 2001; 345:1435-1443
Survival Rates Kirkland, JK, et. al JHLT 2013; 32:141-156
ADLs of DT Patients Kirkland, JK, et. al JHLT 2013; 32:141-156
What Happens to These Patients? • Shock Team Evaluation for mechanical circulatory support (MCS) • Try to avoid the bridge to decision or the bridge to nowhere
Variations of Short-Term VADs • Impella5.0 • Tandem Heart • CentriMag • ECMO (V-A)
Impella5.0 • Utilized for LV support only; not appropriate to use with RV failure • Impella5.0 inserted via femoral or axillary artery cut down; provides up to 5L of flow • The catheter is advanced through the ascending aorta into the left ventricle • Pulls blood from an inlet near the tip of the catheter and expels blood into the ascending aorta • FDA approved for support of up to 6 hours
TandemHeartpVAD • Used for LV support; not appropriate in RV failure • Cannulas are inserted percutaneously through the femoral vein and advanced across the intraatrial septum into the left atrium • The pump withdraws oxygenated blood from the left atriumand returns it to the femoral arteries via arterial cannulas • Provides up to 5L/min of flow • Can be used for up to 14 days
CentriMag • Can be used for LV and/or RV support • Cannula are typically inserted via a midline sternotomy • Capable of delivering flows up to 9.9 L/min • Can be used for up to 30 days
ECMO (V-A) • Used for patients with a combination of acute cardiac and respiratory failure • A cannula takes deoxygenated blood from a central vein or the right atrium, pumps it past the oxygenator, and then returns the oxygenated blood, under pressure, to the arterial side of the circulation • Can be used for days to weeks
Summary • The management of advanced heart failure is a dynamic process that requires frequent re-evaluation • Timing of LVAD placement is critical • LVADs for DT have been shown to improve mortality rates and quality of life • There are short-term VAD options available for emergent situations
Case Study LN is a 34 year old female with a past medical history of peripartum cardiomyopathy following the vaginal delivery of her first child nine months ago. Her LVEF is 20%, and she has NYHA class IV symptoms. She has been on optimal medical therapy including carvedilol, captopril, aldactone, and lasix. In addition, she was started on an outpatient milrinone infusion at 0.25 mcg/kg/min one month ago. She has been listed for heart transplantation, but due to her blood type of A- and her body habitus, it is unlikely that a donor heart will be found quickly.
Case Study Based on the cast study presented, LN’s peripartum cardiomyopathy would fall into which of the following categories: A) Ischemic cardiomyopathy B) Non-ischemic cardiomyopathy
Case Study LN is undergoing evaluation for LVAD placement. Based on the case study, LN would fall into which LVAD category? A) Destination therapy B) Bridge to transplantation C) Bridge to nowhere D) Bridge to decision
Case Study LN asks about the benefits of having an LVAD placed. Which of the following statements is TRUE regarding LVAD placement as a bridge to transplantation? A) Patients are guaranteed a transplant if they get a LVAD B) Most LVAD patients see an improvement in their ability to carry out their usual activities of daily living C) A LVAD will make her heart failure resolve D) She will be able to stop all of her heart failure medication shortly after LVAD placement
Case Study Some of the long-term risks associated with LVAD placement include which of the following: A) Infection B) GI bleed C) CVA D) All of the above
Case Study As the ACNP preparing to care for LN in the immediate post-operative period, you recognize that the following issues will likely be present: A) LN may be afterload sensitive B) LN may be preload sensitive C) LN will likely be pulseless due to her continuous flow LVAD D) All of the above
Case Study True/False: If LN’s heart failure continues to advance, you know that it’s an easy decision to throw her on a short-term VAD such as a TandemHeart or CentriMag. • True • False