Case Report:
A 61-year-old woman presenting with dyspnea and acute chest pain on an
emergency base rapidly was diagnosed with anterolateral ST-elevation
myocardial infarction (Creatinin kinase (CK); 2498 U/l, CK-MB; 173U/l,
Troponin T; 5668 ng/l). Coronary angiography revealed long segment
severe stenosis of left anterior descending (LAD), severe stenosis in
the proximal marginal branch of circumflex artery (RM), and segment 2 of
the right coronary artery (Fig 1). Due to CS, Impella CP (by Abiomed)
was implanted in the cath lab through the right femoral artery as
”bridge therapy,” and the patient was immediately transferred to undergo
CABG. Salvage on-pump CABG was performed with coronary bypasses to the
LAD by the left mammary artery, to RM and posterior descending artery by
a saphenous vein segment. In order to avoid damage to the Impella during
aortic cross clamping and proximal anastomosis of the bypass grafts
Impella CP was removed. Due to severe LV dysfunction venous-arterial
extracorporeal membrane oxygenation (va-ECMO; Centrimag, by Abbott) via
the right femoral vessels was inserted. Myocardial markers showed a
satisfactory course 6 hours after CABG with clear drop in CK (1504 U/l)
and CK-MB (58U/l).
On 7th postoperative day (POD), however, transthoracic
echocardiography (TTE) showed still severely impaired systolic LV
function with global hypokinesia and moderate distention (ejection
fraction; EF 20%), while respiratory function showed no signs of
impairment. Therefore, it was decided to attempt a switch from va-ECMO
to isolated temporary left ventricular support and unloading by Impella
5.0 in the intention of downgrading the level of support. In the
operation room, a 10mm vascular graft was anastomosed to the right
axillary artery. However, under transesophageal echocardiography (TEE)
as well as fluoroscopic control the Impella 5.0 could not be introduced
beyond the subclavian artery. In this situation, the strategy was
changed, and the arterial line of the va-ECMO was first transferred from
the femoral artery to the axillary artery via already existing
prosthesis. Then a further 10mm silver-coated prostheses was sewn on the
right common femoral artery, and Impella 5.0 was successfully implanted.
Nevertheless, the weaning of va-ECMO was impossible with maximum flow
rates through Impella 5.0 ranging 2.0-2.5 L/min under P3-4 and
additional va-ECMO support of ca. 2.5 L/min (Fig. 2a) . The
patient was transferred to the ICU and demonstrated signs of right
ventricle (RV) failure with central venous pressure 23 mmHg when va-ECMO
weaning below 1.5 l/min was attempted. Therefore, a percutaneous RV
assisted device (Tandem-Heart ProtekDuo by LivaNova; run by Centrimag
pump) with integrated oxygenator was implanted via the right internal
jugular vein on 10th POD, allowing termination of
va-ECMO therapy and enabling Impella 5.0 flows reaching a full range of
5.0 L/min for the first time (Fig. 2b) .
On 14th POD, TEE demonstrated an external compression
of RA and RV. After hematoma removal via re-sternotomy TEE showed
sufficient recovery of LV and Impella could be removed. The oxygenator
was withdrawn from the RVAD support on 27th POD. TTE
demonstrated LVEF recovered to 50% with hypokinesis at the septal and
posterior wall, mild mitral regurgitation, mild to moderately depressed
RV function. After pharmacological conditioning with Levosimendan,
Tandem-Heart was successfully removed on 31st POD. Due
to wound healing disorders a further treatment by plastic and
reconstructive surgery became necessary and the patient was finally
discharged for rehabilitation on the 160thpostoperative day.