Apico-Biaxillary Bypass for an Aortic Stenosis Patient With Severe Calcification of the Entire Aorta
A 70-year-old man with severe aortic stenosis was referred with repeated hospitalization for congestive heart failure for 1 year and a 1-month history of serious hypotension during every hemodialysis. He had been treated for diabetes mellitus for 28 years and had been undergoing hemodialysis for 5 years. Medical history included iliac and femoral arterial atherosclerosis treated with catheter and surgical interventions. Transthoracic echocardiography showed elevation of the systolic aortic transvalvular gradient (peak gradient, 67 mm Hg; mean gradient, 42 mm Hg), aortic valve area of 0.8 cm2 measured by the continuity equation, and mild aortic regurgitation (Figure 1, Movie I in the online-only Data Supplement). Coronary angiography demonstrated 75% stenosis of the left anterior descending artery. Computed tomography revealed severe calcification of arterial system, particularly of the entire aorta, except for the bilateral axillary arteries (Figure 2). Conventional aortic valve replacement was regarded as a difficult procedure because of the necessity for aortic cannulation, aortic cross-clamp, and aortotomy.
We considered a modification of apico-aortic bypass (AAB) as a surgical treatment. AAB connects the apex of the left ventricle (LV) to the descending aorta with an artificial graft containing a bioprosthetic valve through a left thoracotomy. In our AAB procedure, the apico-aortic conduit had been divided into 3 pieces: the first piece of the conduit for the apical anastomosis, the second piece as the composite graft containing a bioprosthetic valve, and the third piece for the distal anastomosis to the descending aorta. We decided to change the third piece of the conduit into a Y-shaped artificial graft and to perform an “apico-biaxillary” bypass through a median sternotomy without any manipulation of the aorta. After a standard median sternotomy, the pericardium and bilateral pleural cavity were opened to provide for the conduit of the apico-biaxillary bypass. A 10 mm ring-reinforced artificial graft (Gelsoft ERS; Vascutek, Renfrewshire, Scotland) was anastomosed end to side to the bilateral axillary arteries. This artificial graft was connected to the arterial lines of the cardiopulmonary bypass. A 22 mm artificial graft (Gelseal; Vascutek, Renfrewshire, Scotland) as the first conduit was anastomosed directly to the apex of the LV under mild hypothermia of 28°C and ventricular fibrillation. After defibrillation, a 22 mm artificial graft containing a 19 mm bioprosthetic valve (Perimount Magna; Edwards Lifesciences, Irvine, Calif.) as the second conduit was anastomosed to the first graft. The proximal portion of a Y-shaped artificial graft (Hemashield; Maquet Cardiovascular LLC, Wayne, N.J.) as the third conduit was anastomosed to the second graft. The 10 mm ring-reinforced artificial graft that was anastomosed to the left axillary artery was disconnected from the arterial line and led into the left pleural cavity through the second intercostal space. This graft was anastomosed to a distal portion of the Y-shaped graft. Concomitant coronary artery bypass grafting was done with the anastomosis of the left internal mammary artery to the left anterior descending coronary artery under on-pump beating fashion. After termination of the cardiopulmonary bypass, the right-side 10 mm graft was anastomosed to the other distal portion of the Y-shaped graft with the same procedure as the left side for completion of the apico-biaxillary bypass. The patient’s hemodynamic conditions were improved dramatically, and he recovered uneventfully. Postoperative 3-dimensional reconstructed computed tomography showed the valved conduit connecting the apex of the LV to the bilateral axillary artery without angulations (Figure 3). Magnetic resonance imaging showed bidirectional ejection from the LV to the ascending aorta and the conduit (Figure 4, Movie II in the online-only Data Supplement). Magnetic resonance phase-contrast flow measurement (Achieva 1.5T magnetic resonance scanner; Philips Medical Systems, Best, the Netherlands) revealed a 2.12 L/min (56%) forward flow at the ascending aorta and a 1.66 L/min (44%) forward flow at the straight portion of the composite graft (Figure 5).
There is only 1 case report on apico-biaxillary bypass,1 in which a patient with aortic stenosis was operated through a median sternotomy with a plan to perform conventional aortic valve replacement. However, severe calcification of the ascending aorta was observed during the operation, and an apico-biaxillary bypass instead of AAB was performed because the anastomosis of the distal graft to the descending aorta is difficult through a median sternotomy, not because of the calcified descending aorta. Because AAB requires the distal anastomosis to the descending aorta, a patient with a calcified descending aorta is excluded due to the indication of AAB.2 Thus, apico-biaxillary bypass is a feasible option for patients with severe aortic stenosis with severe calcification of the entire aorta.
The online-only Data Supplement is available with this article at http://circ.ahajournals.org/cgi/content/full/121/24/e447/DC1.
Chiu KM, Lin TY, Chen JS, Li SJ, Chan CY, Chu SH. Left ventricle apical conduit to bilateral subclavian artery in a patient with porcelain aorta and aortic stenosis. Circulation. 2006; 113: e388–e389.
Gammie JS, Krowsoski LS, Brown JM, Odonkor PN, Young CA, Santos MJ, Gottdiener JS, Griffith BP. Aortic valve bypass surgery: midterm clinical outcomes in a high-risk aortic stenosis population. Circulation. 2008; 118: 1460–1466.