A total of 640 patients were enrolled in the study. The characteristics of all patients are summarized in Table 1. The patients were categorized into groups according to their age; 573 patients were in the younger group (age > 70 years old) and 67 patients were in the older group (age > 70 years). The mean ages of patients in the younger and older groups were 45.3 ± 9.6 years old and 73.5 ± 3.0 years old, respectively. The mean weight of patients in the older group was lower than that of the younger group. The incidence of diabetes in the younger group (9.2%) were lower than that of the older group (16.4%), but the difference was not statistically significant. The younger group had higher incidence of moderate or severe aortic regurgitation than that of the older group (30.7% vs 17.9%, p < 0.05). The incidences of hypertension, preoperative stroke, chronic lung disease, renal dysfunction, peripheral vascular disease, Marfan syndrome, prior cardiac surgery, and malperfusion syndrome were not significant different between these two groups. In addition, no significant differences were observed between the two groups for left ventricular ejection fraction and end-diastolic dimension detected by echocardiography.
Table 1
The preoperative characters of patients underwent TBSG implantation
Demographics | Total (n = 640) | Younger group (n = 573) | Older group (n = 67) | P value |
Age, y | 52.9 ± 11.3 | 45.3 ± 9.6 | 73.5 ± 3.0 | < 0.001 |
Weight, kg | 72.3 ± 14.6 | 76.5 ± 17.3 | 61.4 ± 9.9 | < 0.001 |
Male, n (%) | 491(76.7) | 446 (77.8) | 45 (67.2) | 0.051 |
Hypertension, n (%) | 521(81.5) | 462 (80.6) | 59 (88.1) | 0.139 |
Diabetes, n (%) | 64(10.0) | 53 (9.2) | 11 (16.4) | 0.064 |
Preoperative stroke, n (%) | 35 (5.5) | 29 (5.1) | 6 (0.9) | 0.185 |
Chronic lung disease (moderate or greater), n (%) | 42 (6.6) | 35 (6.1) | 7(10.4) | 0.185 |
Renal dysfunction, n (%) | 86 (13.4) | 77 (13.4) | 9 (13.4) | 0.999 |
Peripheral vascular disease, n (%) | 46 (7.2) | 40 (7.0) | 6 (0.9) | 0.794 |
Marfan Syndrome, n (%) | 38 (6.8) | 38 (6.6) | 0 | N/A |
Prior cardiac surgery, n (%) | 43(6.7) | 42 (7.3) | 1 (1.5) | 0.282 |
Moderate AR or greater, n (%) | 178(27.9) | 176 (30.7) | 12 (17.9) | 0.029 |
LVEF, % | 62.8 ± 8.1 | 62.7 ± 9.2 | 61.9 ± 8.1 | 0.619 |
LVED, mm | 48.5 ± 7.9 | 48.8 ± 8.4 | 49.0 ± 7.8 | 0.877 |
Malperfusion syndromes, n (%) | | | | |
Cerebral | 32 (5.0) | 29 (5.1) | 3 (4.5) | 0.951 |
Myocardial | 26(4.1) | 23 (4.0) | 3 (4.5) | 0.885 |
Renal | 74(11.5) | 68 (11.9) | 6 (9.0) | 0.481 |
Lower extremity | 29(4.5) | 25 (4.4) | 4 (6.0) | 0.773 |
TBSG: triple branched stent graft; LVEF: left ventricular ejected fraction; LVED: left ventricular end diastolic diameter. |
Surgical data of the patients are shown in Table 2. Patients in the two groups received comparable aortic valve or root procedure, coronary artery bypassing graft, and mitral surgery. The mean durations for CPB, aortic cross-clamp, SCP, and total circulation arrest in the younger group were 145.9 ± 36.3 minutes, 53.8 ± 22.5 minutes, 12.2 ± 4.5 minutes, and 4.6 ± 3.0 minutes, respectively, which were comparable with those in the older group (139.5 ± 26.4 minutes, 47.9 ± 15.7 minutes, 11.7 ± 4. 7 minutes, and 3.7 ± 23 minutes, p > 0.05, respectively).
Table 2
The surgical data of patients underwent TBSG implantation
Demographics | Total (n = 640) | Younger group (n = 573) | Older group (n = 67) | P value |
Aortic valve or root surgery, n (%) | 562 (87.8) | 503 (87.8) | 59 (88.1) | 0.949 |
Aortic valve replacement | 116 (18.1) | 101 (17.6) | 15 (22.4) | 0.338 |
Bentall procedure | 115 (18.0) | 101 (17.6) | 14 (20.9) | 0.51 |
Reconstruction of the sinus of Vaslava | 300 (46.9) | 272 (47.5) | 28 (41.8) | 0.378 |
Valve-sparing root replacement | 31 (4.8) | 29 (5.1) | 2 (3.0) | 0.654 |
Comitant surgery | | | | |
CABG, n (%) | 22 (3.4) | 20 (3.5) | 2 (3.0) | 0.889 |
Mitral surgery, n (%) | 15 (2.3) | 14 (2.4) | 1 (1.5) | 0.952 |
CPB time, min | 145.9 ± 35.6 | 145.9 ± 36.3 | 139.5 ± 26.4 | 0.343 |
Crossclamp time, min | 52.4 ± 20.2 | 53.8 ± 22.5 | 47.9 ± 15.7 | 0.147 |
Selected cerebral perfusion time, min | 12.0 ± 4.5 | 12.2 ± 4.5 | 11.7 ± 4.7 | 0.658 |
Circulation arrest time, min | 4.3 ± 2.8 | 4.6 ± 3.0 | 3.7 ± 23 | 0.111 |
TBSG: triple branched stent graft; CABG: coronary artery bypass grafting; CPB: cardiopulmonary bypass. |
The total drainage volume after surgery (532.9 ± 341.3 mL in younger group vs. 514.7 ± 276.7 mL in older group, p = 0.675) and ventilation time (18.7 ± 7.4 hours in younger group vs. 20.3 ± 10.8 hours in older group, p = 0.11) were comparable in the two groups. Furthermore, the incidences of cardiac reoperation, myocardial infarction, sudden cardiac arrest, neurologic dysfunction, pneumonia, acute respiratory distress syndrome, acute kidney injury, gastrointestinal hemorrhage, sepsis, and sternal infection or dehiscence were similar between the two groups. Patients in the older group had higher incidence of dialysis for acute kidney injury compared with that of the younger group (26.9% vs. 15.2%, p = 0.015), which may result in prolonged ICU stay (67.5 ± 22.0 hours vs. 87.8 ± 33.1 hours, p < 0.05). However, the incidence of 30-day mortality (5.1% in younger group vs. 7.5% in older group, p = 0.407) and length of hospital stay (18.2 ± 11.9 days in younger group vs. 19.6 ± 13.6 days in older group, p = 0.786) were comparable between the two groups.(Table 3)
Table 3
The postoperative data of patients underwent TBSG implantation
Demographics | Total (n = 640) | Younger group (n = 573) | Older group (n = 67) | P value |
The total drainage volume, ml | 541.5 ± 356.6 | 532.9 ± 341.3 | 514.7 ± 276.7 | 0.675 |
Ventilation time, h | 19.0 ± 10.2 | 18.7 ± 7.4 | 20.3 ± 10.8 | 0.11 |
ICU stay, h | 70.4 ± 30.7 | 67.5 ± 22.0 | 87.8 ± 33.1 | 0.028 |
Hospital stay, d | 18.3 ± 14.9 | 18.2 ± 11.9 | 19.6 ± 13.6 | 0.786 |
Cardiac reoperation, n (%) | 9 (1.4) | 8 (1.4) | 1 (1.5) | 0.628 |
Myocardial infarction, n (%) | 8 (1.3) | 7 (1.2) | 1 (1.5) | 0.695 |
Sudden Cardiac arrest, n (%) | 18 (2.8) | 16 (2.8) | 2 (3.0) | 0.764 |
Neurologic dysfunction, n (%) | | | | |
Temporary | 20 (3.1) | 18 (3.1) | 2 (3.0) | 0.763 |
Permanent | 13 (2) | 11 (1.9) | 2 (3.0) | 0.899 |
Pneumonia, n (%) | 430(67.2) | 383 (66.8) | 47 (70.1) | 0.585 |
ARDS, n (%) | 16 (2.5) | 14 (2.4) | 2 (3.0) | 0.885 |
Tracheotomy, n (%) | 56 (8.8) | 49 (8.6) | 7 (10.4) | 0.603 |
AKI, n (%) | 177(27.7) | 152 (26.5) | 25 (37.3) | 0.062 |
AKI required dialysis, n (%) | 105(16.4) | 87 (15.2) | 18 (26.9) | 0.015 |
Gastrointestinal hemorrhage, n (%) | 14 (2.2) | 12 (2.1) | 2 (3.0) | 0.976 |
Sepsis, n (%) | 54(8.5) | 47 (8.2) | 7 (10.4) | 0.532 |
Sternal infection or dehiscence, n (%) | 4 (0.6) | 3 (0.5) | 1 (1.5) | 0.894 |
30-d mortality, n (%) | 34(5.3) | 29 (5.1) | 5 (7.5) | 0.407 |
ICU: intensive care unit; ARDS: acute respiratory distress syndrome; AKI: acute kidney injury. |
Comments
Aortic arch surgery requires transient cerebral circulatory arrest with or without hypothermia, leading to inevitable ischemic injury in the brain or organs 8, 9. The procedure for TAR is more complicated compared with that of a hemiarch repair. Therefore, TAR is associated with higher incidences of death and neurological adverse events (NAE) than those of a hemi-arch repair, especially in an older cohort. Thus, a hemiarch repair is the preferred surgical procedure in an older cohort with ATAAD. However, aortic arch involvement was associated with higher incidences of rupture and reintervention 10–13. The present study showed similar incidences of in-hospital death and major complications between different age groups. This promising outcome suggested that the older cohort, specifically those above 70 years old, may benefit from several advantages of the TBSG technique.
First, the open arch technique could facilitate the implantation of TBSG. All the arch vessel orifices and true lumen of the descending aorta could be easily identified through the arch incision, which resulted in fast and safe implantation of the TBSG. Therefore, the duration of circulatory arrest was short. Second, the short duration of the TBSG implantation allowed for TAR to be performed under moderate hypothermia circulatory arrest; thus, avoiding the potential risk of bleeding and inflammatory response caused by deep hypothermia circulatory arrest. Third, bilateral cerebral perfusion was possible, which provided more physiological and effective cerebral protection during circulatory arrest; thus, the circle of Willis does not need to be considered in this case. Furthermore, TAR only required a single anastomose, resulting in less branched vessels manipulation and reduced the difficulty of achieving hemostasis, which theoretically decreased the incidences of NAE and anastomotic oozing.
Endoleak development might occur after a TBSG implantation, but the incidence was low. This satisfactory result can be attributed to various reasons. First, the diameter of the stented elephant trunk was 10–20% larger than that of the proximal descending aorta, which could effectively prevent retrograde flow from the descending aorta. Second, the main graft portion was anastomosed to the native arch, which serves as the neo-intima of the arch. Third, the proximal end of the main tube graft was directly anastomosed to the Dacron graft, preventing an endoleak from the proximal end of the main tube graft. Furthermore, the base of the brachiocephalic vessels was stitched to prevent the migration of the TBSG. Finally, banding at the bases of the arch vessels was routinely applied when size of the sidearm stent graft was smaller than that of the corresponding arch vessel, which effectively prevented retrograde endoleak from the arch vessels.
Previous studies have reported that organ malperfusion is an independent risk of mortality 14, 15. The distal part of the TBSG served as a stented elephant trunk, which could secure the tear located in the descending aorta, reverse the perfusion of the true lumen, and induce thrombosis in the false lumen of the downstream descending aorta, resulting in reperfusion of the ischemic organs. Reperfusion of organs could improve the perioperative outcomes.