acute right ventricular ( rv ) failure is associated with significant morbidity and mortality , which may develop as a consequence of acute myocardial infarction , pulmonary embolism , myocarditis , ventricular septal defect or post - cardiotomy [ 2 , 3 ] . despite optimal medical management
the rv may exhibit a greater capacity for rapid recovery compared with the left ventricle .
recent studies suggests that most of the patients recover sufficient function to allow explantation of the impella recovery right direct ( irrd ) or right peripheral was reported .
herein we report a case of successful implantation of the irrd in a patient with acute rv failure after previous aortic valve ( av ) replacement despite cabg , maximal medical therapy , intra - aortic balloon counterpulsation ( iabp ) and extracorporeal membrane oxygenation ( ecmo ) .
a 58-year - old woman was admitted in our division due to severe av stenosis with a mean transaortic gradient of 53 mmhg .
on the second postoperative day the patient referred a sharply chest pain , fatigue , vomitus and sweating .
the coronaro - angiography demonstrated a normal visualization of the left coronary and absence of visualization of the right coronary artery .
iabp was placed immediately and an emergent off - pump coronary revascularization consisting in a vein graft to the right coronary artery was performed .
five hours later , the hemodynamic was unstable , and symptoms of tamponade were present , despite maximum medical therapy and iabp .
the patients was sent into the operating room . even with an open sternum , the rv insufficiency was not improved .
ecmo was implanted and with an open sternum the patient was sent into the icu .
then we decided to support the rv with irrd ( abiomed , danvers , ma ) .
purse string suture was made around the right atrial appendage and the inflow cage was introduced to the right atrium and fixed . in the pulmonary artery ( pa ) a purse string suture was made in the middle of distance between the pulmonary valve and division of pulmonary branch .
the tip of the cannula ( outflow tract ) was inserted into the pa ( fig .
the pump was started with slow rotational speed and flow was adjusted to 3.5 l / min .
the thorax was left open because of a large edema of the rv and to sustain this we used a plastic spacer in both margin of the sternum . to cover the wound we employed povidone 
the activated clotting time was maintained between 180 and 200 s. daily the sternal wound was revised .
starting from the second day the pump flow was reduced half litre every day controlling rv function by transesophageal echocardiography and monitoring hemodynamic conditions .
after 9 days of irrd the rv was recovered . the decision to remove the device
4 ) . we examinated the inner surface of the graft after removal and a thin epithelized layer of the inner surface was found without any thrombus formation ( fig .
four days later the patient was extubated and 16 days after irrd explanted the patient was discharged in good clinical conditions . 

figure 1:schematic presentation of the impella right direct implantation.figure 2:the impella right direct implanted.figure 3:removal of the outflow tip of the device.figure 4:removal of the inflow tip of the device.figure 5:there are no thrombus inside the device.figure 6:the outflow tip of the impella device.figure 7:the inflow tip of the device.figure 8:after removal of the device .
acute rv failure is an increasingly common clinical problem and despite optimal medical management , some patients fail to improve and require implantation of a rv assist device , which improves end - organ perfusion and provides an opportunity for reversal of multisystem organ failure .
schmidt et al .   first described its use in 2003 , employing such a device in 8 patients and later christiansen et al .  
subsequently , the device has been used post - cardiotomy , post - transplant , and post left ventricular assist device implantation .
we have described the employment of the irrd in a patient with rv failure due to myocarcial infarction post av replacement , unresponsive to cabg .
there is growing evidence to suggest that the irrd can be successfully used for the treatment of refractory acute rv failure .
the reasons why we choose this device were : ( i ) easy to insert , ( ii ) accommodates patients of all size ( flow rate up to 5.5 l ) , ( iii ) minimal anticoagulation , ( iv ) minimal hemodilution , ( v ) minimal destruction of blood or plasma components , ( vi ) possibility of sternal closure and ( vii ) reduction of myocardial workload and oxygen consumption .
important aspects of blood pumps are lifetime , costs , adaptability to diverse applications and patient requirements , rapid and easy deployment , thrombogenicity , flow characteristics and blood damage .
the major advantages of the irrd are its small size , the simple design , the low energy requirements , and the avoidance of a priming volume .
these figures lead to a reliable pump function without technical failures and may result in a reduced number of transfusion requirements which is reported to be excessively high in patients with ecmo support .
flow and pressure characteristics , shear stress , blood exposure times to artificial surfaces and the size of the pump are important factors contributing to hemolysis .
some studies demonstrated beneficial effects of pulsatile flow , others could not confirm these results .
this might be due to release of endothelium - derived relaxing factor by rhythmic stimulation of endothelial cells through oscillating changes in vessel wall shear stress .
this effect of pulsatile flow does not appear to improve pulmonary gas exchange , peak inspiratory pressure , mean pa pressure , oxygenation capacity and development of pulmonary edema .
it seems to be justified to support the rv with non - pulsatile flow devices , especially when support duration is limited to a few days as in patients with post - cardiotomy failure .
the main disadvantage of the irrd is that implantation requires a sternotomy and direct cannulation of the right atrium and pa .
this increases the risk of bleeding and infection and necessitates an additional operation for device explantation .
these risks are not insignificant , considering that patients requiring implantation of an rv assist device are frequently critically ill with multisystem organ failure and may be coagulopathic due to hepatic congestion and/or the presence of anti - platelet medications .
the impella right peripheral is an alternative to irrd which allows the percutaneous implantation of the device .
the margey et al .   used this device for temporary rv mechanical circulatory support in a similar patient presenting with an inferoposterior st - segment elevation myocardial infarction , who despite revascularization , optimized medical therapy , iabp , remained in profound cardiogenic shock .
we have described the clinical outcome in our patient with refractory acute rv failure supported with the irrd .
our findings suggest that implantation of these devices is clinically feasible , associated with hemodynamic improvement , and facilitate successful bridge - to - recovery in most patients with post - cardiotomy rv failure due to myocardial infarction unresponsive to cabg , maximal medical therapy , iabp and ecmo .
the authors declare that there is no conflict of interest regarding the publication of this article .
 abstracta 58-year - old woman underwent aortic valve replacement . on the second postoperative day the patient referred a sharply chest pain , and an emergent coronary angiography revealed total occlusion of the right coronary artery . 
 an intra - aortic ballon pump was placed and the patient underwent emergent off - pump coronary revascularization of the right coronary artery . 
 five hours later , due to unstable hemodynamic the extracorporeal membrane oxygenation was implanted without improvement of the right ventricular ( rv ) function . 
 then we decided to implant the impella right direct ( rd ) . 
 after 9 days of impella s insertion the rv was recovered and the device was successfully explanted . after 16 days of impella explanted the patient was discharged . 
 this case suggest that implantation of impella rd is clinically feasible , associated with hemodynamic improvement , and facilitate successful bridge - to - recovery in patients with post - cardiotomy rv failure due to myocardial infarction unresponsive to coronary artery bypass grafting , maximal medical therapy , contrapulsation and extracorporeal membrane oxygenation . 
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