Marketing

Biventricular cannulation for the thoratec ventricular assist device

Description
The Thoratec biventricular assist device has been used extensively as a bridge to heart transplantation. Right atrial cannulation has always been used during right ventricular support, however diminished filling and output of the right ventricular
Categories
Published
of 2
All materials on our website are shared by users. If you have any questions about copyright issues, please report us to resolve them. We are always happy to assist you.
Related Documents
Share
Transcript
  Biventricular Cannulation for the ThoratecVentricular Assist Device Francisco A. Arabı´a,  MD  , Venki Paramesh,  MD  , Bruce Toporoff,  MD  ,David A. Arzouman,  MD  , Gulshan K. Sethi,  MD  , and Jack G. Copeland,  MD Section of Cardiovascular and Thoracic Surgery, University of Arizona Health Science Center, Tucson, Arizona The Thoratec biventricular assist device has been usedextensively as a bridge to heart transplantation. Rightatrial cannulation has always been used during rightventricular support, however diminished filling and out-put of the right ventricular assist device have beennoticed when compared with filling and output of theleft ventricular assist device. We describe a technique todirectly cannulate the right ventricle to maximize fillingand output of the right ventricular assist device.(Ann Thorac Surg 1998;66:2119–20)© 1998 by The Society of Thoracic Surgeons T he Thoratec (Berkeley, CA) ventricular assist device(VAD), is a pneumatically driven paracorporealprosthetic ventricle. This system has been used success-fully as a bridge to recovery or transplantation [1, 2].Inflow to the device is obtained from atrial cannulae thatare placed in either the left atrium, right atrium, or both,as dictated by the clinical condition of the patient. Theoutflow conduits are anastomosed to the ascending aorta,pulmonary artery, or both, via a Dacron graft. However,superior VAD filling and output are obtained if the leftpump inflow cannula srcinates from the patient’s leftventricular apex. A special left apical cannula is availablefor this purpose. Inflow cannulation for the right VADhas always required the use of a right atrial cannula. Ourexperience has shown that usually the left VAD canprovide adequate output in this configuration but thatthe right VAD sometimes demonstrates impaired fillingand a compromised output. We describe a technique thatuses an apical cannula in the right ventricle (RV) tomaximize right VAD filling and output.The Thoratec system can be installed in different con-figurations as a single VAD or as a biventricular assistdevice. The outflow cannulae are anastomosed to thegreat vessels, which sometimes can be accomplishedwithout cardiopulmonary bypass. When the device isintended as a bridge to transplant, it is recommendedthat the inflow cannula to the device be anastomosed tothe left ventricular apex. Cardiopulmonary bypass isrequired when the left ventricular apical cannula andright ventricular cannulation are used. Technique The ascending aorta is cannulated with a conventionalcanola and the right atrium is cannulated with a two-stage cannula. The left ventricle can be decompressedwith a right superior pulmonary vent. The outflow con-duits (aorta and pulmonary artery) are tunneled underthe skin into the mediastinum and anastomosed to itsrespective great vessel by using 4-0 polypropylene. Car-diopulmonary bypass is then initiated and the apex of theheart is lifted. Six to eight interrupted pledgeted sutures(2-0 blue braided polyester fiber) are placed around thecircumference of the apex. The apex is cored out. Thediameter of the core is approximately 1 cm. The leftventricular beveled apical cannula is tunneled under theskin and brought into the pericardial space. The cannulais now inserted in the left ventricular apex, and thesutures are passed through the felt ring and tightened(Fig 1). The left ventricular cannula is now passedthrough the tunnel and clamped above the skin.Transesophageal echocardiography can be helpful indetermining the best location to place the right ventric-ular cannula. The cannula enters the right ventricle Accepted for publication June 17, 1998.Address reprint requests to Dr Arabı´a, Cardiovascular and ThoracicSurgery, College of Medicine, University of Arizona Health SciencesCenter, PO Box 245071, Tucson, AZ 85724-5071.  Fig 1. Left ventricular apical cannulation. © 1998 by The Society of Thoracic Surgeons 0003-4975/98/$19.00Published by Elsevier Science Inc PII S0003-4975(98)01085-6  though the diaphragmatic wall, superior to the posteriordescending artery. The beveled end of the cannula isplaced facing the tricuspid valve to optimize inflow intothe right VAD. Six to eight pledgeted sutures (2-0 bluebraided polyester fiber) are placed on the diaphragmaticsurface of the right ventricle (Fig 2). A purse-string suturecan be placed through the peldgets to provide additionalhemostasis, as the right ventricle is thin in this location. Asmall core of right ventricular wall is removed, and thecannula is placed in the area between the pledgets. In asimilar fashion, the pledgeted sutures are placed throughthe felt ring and tightened. The purse-string suture thatwas placed through the pledgets is now tightened. Suturereinforcement of the right ventricular cannula might berequired to secure hemostasis.Once all the inflow and outflow cannulae are anasto-mosed to the heart and great vessels, they are connectedto the VADs (Fig 3). Air is then removed from the system,the patient is placed in the Trendelenberg position. Thepatient is weaned from cardiopulmonary bypass by al-lowing the VAD or biventricular VADs to take over thecirculation by increasing the its rate and decreasing thecardiopulmonary bypass flow rate. Comment This new arrangement of cannulae might provide supe-rior flows for the Thoratec biventricular assist device. Itcould allow for faster postoperative recovery in thepatients who have advanced manifestations of end-organdysfunction. References 1. Arabia FA, Copeland JG, Larson DF, Smith RG, CleavingerMR. Circulatory assist devices: applications for ventricularrecovery or bridge to transplant. In: Gravlee GP, Davis RF,Utley JR, eds. Cardiopulmonary bypass: principles and prac-tice. Baltimore: Williams & Wilkins, 1993:693–712.2. Hill JD, Farrar DJ. The Thoratec VAD system: patient selec-tion and clinical results in bridging to transplantation. In:Lewis T, Graham TR, eds. Mechanical circulatory support.London: Edward Arnold, 1995:169–75.  Fig 2. Right ventricular cannulation. Fig 3. Relative positions of cannulae with biventricular cannulation. 2120  HOW TO DO IT ARABI´A ET AL Ann Thorac SurgBIVENTRICULAR CANNULATION 1998;66:2119–20
Search
Similar documents
View more...
Tags
Related Search
We Need Your Support
Thank you for visiting our website and your interest in our free products and services. We are nonprofit website to share and download documents. To the running of this website, we need your help to support us.

Thanks to everyone for your continued support.

No, Thanks
SAVE OUR EARTH

We need your sign to support Project to invent "SMART AND CONTROLLABLE REFLECTIVE BALLOONS" to cover the Sun and Save Our Earth.

More details...

Sign Now!

We are very appreciated for your Prompt Action!

x