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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 27, No 4, July/August 2016



velocity was 0.9


0.2 (0.8–1.2) m/s, and aortic valve opening was

observed every one-to-one cycle or one-to-three cycle.

Since eight patients had ischaemic cardiomyopathy and

one had had coronary artery bypass grafting (CABG) 10

years earlier, remission of their end-stage heart failure was

not expected. All our patients had had automated internal

cardioverter defibrillator (AICD) and cardiac resynchronisation

therapy (CRT-D) implantation prior to the LVAD implantation.

One patient had a ventricular fibrillation (VF) event in the ward

and had cardiopulmonary resuscitation. He had his AICD-

CRT-D implanted prior to the LVAD surgery. Two patients

had experienced ventricular tachycardia (VT) at home due to

dehydration during the summer, and their AICD had been

interrupted during the attacks.

There were a few hospitalisations because of minor

complications. One patient complained of a coffee-grinding

noise coming from his pump three months post-implant, and

the remote monitoring system also documented frequent excess

current alarms and increased power at different hours of the day.

The patient was hospitalised for possible thrombus formation

or device malfunction. The data were analysed at Micromed

Cardiovascular Inc, Houston, Texas. The coagulation profile was

in the normal range for a LVAD patient, his INR was 3.2, and

his lactate dehydrogenase level was 606 U/l, which was gradually

elevated up to 120 days after LVAD implantation.

Serial echocardiographic studies were done weekly to rule out

possible thrombus formation in the left ventricle, the orifice of

the inflow cannula, outflow conduit and aortic valve cusps. The

patient received heparin infusion with close monitoring of his

coagulation profile. There was no absolute finding in the echo

studies to confirm thrombus formation or determine the reason

for the coffee-grinding noise, since we were not able to visualise

the titanium impeller. We guessed that there may have been a

blood clot there, which caused the increased power. The noise

stopped after the fifth day of heparin infusion.

A female patient had uncontrolled diabetes, she had gradually

gained 7 kg by the sixth month post-operatively, and suffered

from recurrent urinary tract infections. She was admitted with

fever, tachycardia, post-diabetic ketoacidosis and documented

urinary tract infection. Her echocardiographic study was done

in a sub-optimal position due to her tachycardia. She received

anti-arrhythmic and antibiotic regimens, and a few days later she

was in sinus rhythm, her heart rate was 89–95 beats per minute,

and her fever was gone. Her echo studies were repeated and

LVAD optimisation was done. She was discharged from hospital

with 9 500 rpm, her CO was 4.7 l/min and the pulsality index

was 2.31 m/s.

Four patients were followed up for more than two years, and

two for more than a year. Three patients died due to multi-organ

failure. One international patient had heart transplantation in

the Republic of China. The longest supported patient was for

more than three years, with a good quality of life.


All data for each patient had been collected in each portable

console, Heart Attendant (Micromed Cardiovascular Inc,

Houston, TX), so with the universal serial bus (usb) connection,

all the data could be downloaded and could be easily analysed.

Online connection of the Heart Attendant to the internet assists

in patient care and provides 24 hours a day, seven days a week

monitoring of the LVAD patient. This technology decreases

hospital admissions for each alarm detection, as the clinicians

can track the patient with the remote monitoring system and

help him/her by phone.

This technology differentiates Heart Assist 5 LVAD from

other continuous-flow pumps. The implantable flow probe

also helps to assess even minor dehydration problems, which

can be solved without admission to hospital. We experienced

low-flow alarms during the summer months and suggested our

patients take in extra fluid during summer.


Fine-tuning of

the Heart Assist 5 LVAD with the implantable flow probe and

portable console was convenient, and the LVAD speed change

echo studies enabled easy optimisation of the device during

in-hospital echocardiographic studies.

There are reports of large single-centre echocardiographic

studies of other continuous-flow and centrifugal pumps in the



These pumps have been approved by the United

Fig. 5.

Evaluation of aortic valve opening times with M mode


Fig 6.

Left ventricular inflow cannula visualisation with 3D