Page 404 - fbkCardioDiabetes_2017

380 Mechanical Circulatory Support for
Advanced Heart Failure

aorta). However, the axial and centrifugal pumps to heart-kidney transplantation), biopsy proven liver
differ in their hydrodynamic performance, as char- cirrhosis,active or recent history (within 3 months)
acterized by the relation between flowrate and head of heparin induced thrombocytopenia, irreversible
pressure. Axial flow pumps have a steep and inverse- cognitive dysfunction (as established by formal neu-
linear relationship between flow and head pressure, rocognitive testing) andmarked frailty. Patients are
while in centrifugal pumps this relationshipis flatter also deemed to not be good candidates for implan-
and more susceptible to head pressure changes tationif they lack social support or have a recent or
(i.e., more sensitive topre-load and afterload). Due to active history of significant alcoholor illicit substance
these hydrodynamic characteristics, with the same use. Older patients (older than 80 years) or morbidly
change in pressure, centrifugal pumps generate larg- obesepatients (body mass index above 45 kg/m2)
er changes in flow and yield more pulsatile wave- should be evaluated on case-by-case basis.
forms, more accurate flow estimation, and have a
lower risk of suction events (insetting of dehydration, Current Clinical Results with Continuous
arrhythmias, or right ventricular failure), but are more Flow Pumps
dependenton the loading conditions when compared
with axial flow pumps. Several modern trials with ventricular assist devices
have been presented in the lastdecade, with one-year
survival ranging from 68% (in the initial Abbott Heart-
Patient Selection
Mate II bridge to transplant and destination therapy
The patients most likely to benefit from long-term trials and Medtronic HVAD destination therapy trial)
use of ventricular assist devices are patients with ad- to 86% (Medtronic HVAD bridge to transplant trial,
vanced heart failure,preferably INTERMACS profiles Abbott HeartMate II post approval studies). Asdis-
3-4, where the surgical risk of implantation is fairly cussed before, patients with INTERMACS profiles
small (in-hospital mortality less than 3-5 %). Patients 3-7 had better survival,slightly greater than 90% at
with INTERMACSprofiles 1-2 should be bridged with one year.
temporary mechanical circulatory supportdevices
and their end-organ function and nutritional status The use of ventricular assist devices has been ham-
improved significantly or normalized in order to de- pered by the relatively high probability of device re-
crease the surgical mortality and morbidity associat- lated adverse events (rates per 100 patient-months):
ed withthe durable ventricular assist devices implant. bleeding– mainly gastrointestinal (early [within first
Ideal candidates are patients with large left ventri- 90 days post implant] of 19.6 andlate [90 days to
cles, relatively preserved rightventricular function, 24 months post implant] of 3.25); infections – mainly
elevated left ventricular filling pressures and low driveline infections (early of 16.95 and late of 4.06),
cardiac output,with competent aortic valve, without strokes (early of 4.64 and late of 1.21); and pump
history of gastrointestinal bleeding, compliant,with thrombosis or mechanical failure (early of 2.79 and
adequate social support, and with few extracardiac late of 1.53). In addition, significant right heart failure
comorbidities that could limit the long-term benefit of can occur in up to 30% of patients,and 5-10 % require
ventricular assist devices. Carefully selected patients insertion of a temporary or permanent right ventric-
with restrictive cardiomyopathy, incessant ventricular ular assist device. Up to 30% of patients will develop
tachycardia or congenital heart disease could also over time aortic insufficiency,which may be related
benefit from ventricular assist device implantation. to the degree of opening allowed by the ongoing
ventricular assist device settings. The hospitalization
The absolute medical contraindications to implanta- rates for device related complications are high,with
tion include recent stroke (within 3 months), active reportedly up to 70% of patients being hospitalized
systemic infection, uncorrectable peripheralvascular at least once during thefirst year on support. Howev-
disease or aortic disease, severe irreversible lung dis- er, as shown in the ROADMAP trial, the implantation
ease (forced expiratory volume in first second less of less sick patients, may lead to lower complication
than 1 L or diffusing capacity of the lungs for car- rates and allow for betterhospital free survival.
bonmonoxide less than 35 % of predicted values),
severe cardiac cachexia (body massindex below 19 In Hospital Management
kg/m2, serum albumin level below 2.5 g/dL, or se-
rum pre-albuminlevel below 15 mg/dL), end stage Once the patient is deemed to be a suitable candi-
renal disease on dialysis or with high likelihood of date for ventricular assist device implantation, preop-
needing dialysis post implant (e.g. creatinine above erative optimization using a multi-systems approach
3 mg/dL, unless the patient is considered as bridge prepares the patient for thebest chance of a suc-
cessful outcome. Although several risk scores have

GCDC 2017