Surgical Repair for Acute Type A Aortic Dissection in Octogenarians Division of Thoracic and Cardiovascular Surgery, Johann Wolfgang Goethe University, Frankfurt am Main, Germany

Background. Despite limited data, the necessity for immediate surgical intervention in octogenarians with acute type A aortic dissection (AAD) has recently been questioned because the surgical risk may outweigh its potential benefits. At the same time, evolving stent graft technologies are pushing in the market for pathology within the ascending aorta, even for treatment of AAD. Against this background, we analyzed our institutional experience in this patient cohort during the last 8 years. Methods. Between October 2005 and October 2013, 39 patients aged older than 80 years (82 ± 2 years) underwent surgical repair for AAD, of which 29 patients (74%) were men. Owing to patient age and comorbidities, we aimed to limit the operation to supracoronary hemiarch replacement whenever possible. Clinical data were prospectively entered into our institutional database. Late follow-up was 3.6 ± 2.8 years and was 100% complete. Results. Hemiarch replacement was performed in 32 patients (82%), and full arch replacement was necessary in the remaining 7. In 31 patients (79%), the aortic

root could be glued and reconstructed or remained untouched. The remaining 8 patients (21%) underwent the bio-Bentall procedure. Mean ventilation time was 46 ± 23 hours, and the intensive care unit stay was 5 ± 9 days. We observed new postoperative permanent neurologic deficits in 2 patients (5%) and transient neurologic deficits in 3 (8%). The 30-day mortality was 26% (n [ 10). Kaplan-Meier estimates for late survival were 46% ± 16% at 5 years. Conclusions. Given the guidelines regarding the predicted risk of death in patients with untreated AAD, current data suggest a survival benefit with immediate open surgical intervention even in octogenarians. Similarly to the early days of transcatheter-based aortic valve implantation, open surgical reference data are warranted to set the bar for upcoming endovascular treatment of AAD in octogenarians.


aortic valve implantation, evolving, less invasive procedures for AAD will first be justified in elderly high-risk patients with a prohibitive risk of open surgical repair and have to withstand the comparison with the established gold standard. Data on outcomes in octogenarians after repair of AAD are limited. Thus, the purpose of the current investigation was to report our institutional experience in this particular patient cohort during the past 8 years applying our institutional perfusion and temperature management protocol.

ife expectancy is steadily increasing and will be accompanied by a higher incidence of cardiovascular diseases, including acute type A aortic dissection (AAD) [1]. Recent data of the Statistical Office of the European Union revealed that the portion of octogenarians grew from 1.5% in 1960 to 4.8% in 2007 and will reach 7.4% in 2030 [2]. Open surgical treatment of AAD remains a challenging task, especially in elderly high-risk patients. At the same time, untreated AAD has a high mortality rate that reaches approximately 7% within 1 hour after the onset of symptoms and can rise to more than 90% within 24 hours [3–5]. The first endovascular attempts to treat AAD in octogenarians have recently been presented with the aim of reducing perioperative and postoperative complications [6–9]. However, more routine clinical implementation of thoracic endovascular aortic repair (TEVAR) for treatment of AAD in the ascending aorta, with its unique anatomic restrictions, will likely remain under development for some more years. Similarly to transcatheter

Accepted for publication Aug 6, 2014. Address correspondence to Dr Zierer, Division of Thoracic and Cardiovascular Surgery, Johann Wolfgang Goethe University, Theodor Stern Kai 7, 60590 Frankfurt am Main, Germany; e-mail: [email protected].

Ó 2015 by The Society of Thoracic Surgeons Published by Elsevier

(Ann Thorac Surg 2015;99:547–51) Ó 2015 by The Society of Thoracic Surgeons

Material and Methods Between October 2005 and October 2013, 39 consecutive patients aged older than 80 years underwent emergency operations for AAD at the Division of Thoracic and Cardiovascular Surgery, Johann Wolfgang Goethe University, Frankfurt am Main, Germany. The Institutional Review Board approved the study, and individual patient consent for the study was waived. Relevant clinical characteristics of our patients, consisting of 29 (74%) men and 10 (26%) women, are summarized in Table 1. Mean age was 82  2 years. All patients demonstrated substantial comorbidities. Three 0003-4975/$36.00


Ali El-Sayed Ahmad, MD, Nestoras Papadopoulos, MD, Faisal Detho, MD, Edin Srndic, MD, Petar Risteski, MD, Anton Moritz, MD, and Andreas Zierer, MD



Ann Thorac Surg 2015;99:547–51

Table 1. Patient Characteristics


Characteristic Age, y Male Acute type A dissection Coronary artery disease Aortic valve regurgitation >2 degree Aortic valve stenosis Arterial hypertension Intubated pre-op neurologic dysfunction Chronic obstructive pulmonary disease Renal failure requiring hemodialysis Previous cardiac operation

No. (%) or Mean  SD (N ¼ 39) 82  2 29 (74) 39 (100) 15 (38) 12 (31) 4 (10) 28 (72) 7 (18) 21 (54) 14 (36) 2 (5)

SD ¼ standard deviation.

patients were referred to our center intubated with unknown neurologic status. Two of these patients were admitted to the operating room in coma in unstable hemodynamic condition with continuous cardiopulmonary resuscitation, and both died during the initial hospitalization. Another 4 patients were primary symptomatic with a neurologic disorder consisting of dysarthria (n ¼ 1) or hemiplegia (n ¼ 3). Arterial hypertension was the most prevalent comorbidity (72%), followed by chronic obstructive pulmonary disease (54%) and concomitant aortic valve pathology (regurgitation, 31%; stenosis, 10%). Two patients had undergone previous coronary artery bypass grafting. An iatrogenic AAD occurred in 2 patients during coronary angiography, and they underwent complete myocardial revascularization during the operation. Contrast computed tomography scans were available in all patients and transesophageal echocardiography was routinely performed in the operating theater for confirmation of diagnosis, to detect pericardial effusion, and to assess aortic valve pathology and cardiac function. According to our institutional policy as an aortic referral center, no patient was refused surgical intervention simply because of age or concomitant diseases during the study period.

temperature management protocol as previously described in detail [10–15]. Briefly, the left radial artery and one of the femoral arteries was cannulated for continuous blood pressure monitoring. Temperature probes were placed for esophagopharyngeal and rectal or bladder temperature monitoring. We used a rectal temperature probe until 2007 and replaced it by bladder temperature monitoring thereafter. The patient was positioned supine on the operating table. The right axillary artery was directly cannulated with an 18F to 22F flexible arterial cannula (Edwards Lifesciences, Irvine, CA) whenever possible (n ¼ 34 [87%]), followed by cannulation of the right atrium in a standard fashion. Alternatively, cardiopulmonary bypass (CPB) was established through femoral artery cannulation. The acid-base balance was maintained using the alpha-stat method. CPB was started, and cooling was limited to 28  1 C (range, 26 to 29 C) by rectal temperature, depending on the expected time of arch repair according to the findings on the preoperative computed tomography scan. The innominate and left carotid artery were snared with silicone elastomer loops and occluded at the initiation of selective antegrade cerebral perfusion (ACP). After opening the aortic arch, the left subclavian artery was blocked by insertion of a Fogarty catheter (Edwards Lifesciences). At that point, the elastomer loop snared around the left common carotid artery was temporarily loosened, and an arterial catheter was placed inside the vessel for bilateral ACP. This arterial catheter was simply connected as a side branch to the arterial CPB cannula. Bilateral ACP was the method of choice between 2005 and 2010. After 2010, there was a trend toward unilateral ACP to avoid the potential risk of creating cerebral emboli while manipulating the arch vessels during insertion of the second arterial inflow cannula [15]. Selective ACP was conducted with a perfusate temperature of 28 C in a pressure-controlled manner. The perfusion pressure was controlled on the pump unit and kept at 75 to 85 mm Hg, allowing for a mean flow of 1.2  0.3 L/min. At that point, the arch resection or repair was performed according to our routine protocol [10–15]. Associated coronary artery grafting procedures, if necessary, were conducted after the aortic repair. Neurovascular monitoring consisted of cerebral saturation assessment using near-infrared spectroscopy.

Follow-Up Clinical data from the initial hospitalization were prospectively entered into our institutional database. Discharged patients were assessed directly in our outpatient clinic after 6 months and yearly thereafter or were contacted by mail or telephone interview during a 2-month late closing interval ending in October 2013. Resulting late follow-up was 3.6  2.8 years and was 100% complete.

Operative Technique Since 2005 all attending surgeons at our unit follow the institutional surgical as well as perfusion and

Statistical Analysis All perioperative data were collected prospectively. For the purpose of this study, temporary neurologic dysfunction (TND) was defined as the presence of reversible postoperative motor deficit, confusion, agitation, or transient delirium. The computed tomography findings were required to be normal, with resolution of all symptoms before discharge. Permanent neurologic deficit (PND) was defined as the presence of new focal (stroke) or global (coma), and was confirmed by means of computed tomographic scanning or magnetic resonance imaging of the brain. Thirty-day mortality was defined as

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Results Mean CPB time was 163  47 minutes, and the mean myocardial ischemic time was 103  36 minutes. ACP was used in 39 patients (100%). Isolated cerebral perfusion time was 37  19 minutes. Replacement of the ascending aorta and the proximal aortic arch was performed in 32 patients (82%), and total replacement of the aortic arch was performed in 7 (18%). The aortic root in 31 patients (79%) was glued and reconstructed or remained untouched. The bio-Bentall procedure was performed in the remaining 8 patients (21%). Coronary artery bypass grafting was necessary in 2 patients (5%; Table 2). Mean ventilation time was 46  23 hours. Mean intensive care unit stay was 5  9 days. Mean chest tube drainage within first 24 hours was 760  250 mL. Reexploration for bleeding or tamponade had to be performed in 5 patients (13%). Median hospital length of stay among surviving patients was 15  6 days. The right axillary artery was directly cannulated in 34 patients (87%). Cannulation of the femoral artery was Table 2. Perioperative Results and Surgical Procedures Variable Cardiopulmonary bypass time, min Cross-clamp time, min Isolated cerebral perfusion time, min Core temperature,  C Cerebral perfusion flow, mL/min Ascending and hemiarch Aortic root reconstruction Aortic root untouched Aortic valve conduit Coronary artery bypass grafting Intensive care unit stay, d Ventilation time, h Post-op renal failure requiring hemofiltration Chest tube drainage, mL/24 h Reexploration for bleeding Transient neurologic deficit Permanent neurologic deficit Thirty-day mortality SD ¼ standard deviation.

No. (%) or Mean  SD (N ¼ 39) 163  47 103  36 37  19 28  1 1,190  260 32 22 9 8 2

(82) (56) (23) (21) (5)

59 46  23 5 (13) 760  250 5 (13) 3 (8) 2 (5) 10 (26)

performed in 5 patients (13%). Direct cannulation of the axillary artery did not result in malperfusion or compartment syndrome of the arm in our patient cohort. New postoperative neurologic complications, such as PND, occurred in 2 patients (5%), and TND was detected in 3 (8%). Of the 2 patients with PND, a focal stroke occurred in 1 and coma developed in 1. Most of the TNDs in the present series were temporary delirium (n ¼ 2). A transient motor deficit isolated to the right arm developed in 1 patient as a result of intraoperative constriction of the brachial plexus. All of these TNDs resolved completely at discharge from the hospital. The 30-day mortality was 26% (10 patients). Table 3 contains all causes of death. The Kaplan-Meier estimate for late survival at 5 years was 46%  16%. Figure 1 shows the Kaplan-Meier survival curve. During the follow-up, no patient required reoperation on the proximal or distal aorta. Of the 26 patients, 22 (85%) were discharged to rehabilitation hospitals for 3.6  1.3 weeks and returned back to normal life thereafter. “Normal life” means living at home (18 of 26 [69%]) or in nursing homes (4 of 26 [15%]). Only 4 patients experienced an impaired way of life after the operation: 2 had to move from their own homes to nursing homes, and another 2 moved from nursing homes to long-term care facilities.

Comment Cardiovascular surgery today is facing an increasing number of elderly patients due to steadily rising life expectancy. The population in the United States will include more than 25 million people older than 80 years in 2050 [16]. That increased age is associated with adverse outcome after cardiovascular interventions [17–19], including operations for AAD, is common sense and has been demonstrated in various publications [20–22]. With no doubt AAD is one of the most lethal emergencies in cardiovascular surgery, especially in the elderly. Despite technical improvements in surgical strategies as well as in perioperative and postoperative management options for AAD, these emergency procedures are still associated with a high incidence of postoperative complications and considerable operative mortality rates ranging from 10% to 67% [4, 5, 23, 24]. In the face of such a high risk of morbidity and death, we may consider that octogenarians should potentially be declined for immediate surgical intervention for AAD.

Table 3. Causes of In-Hospital Death Cause of Death Multiorgan failure Respiratory failure Stroke Gastrointestinal bleeding Low output syndrome

No. (%) (N ¼ 39) 5 2 1 1 1

(50) (20) (10) (10) (10)


death during the initial hospitalization or within 30 days postoperatively for discharged patients. Data are presented as mean  standard deviation. Actuarial survival curves were estimated with the standard nonparametric Kaplan-Meier method. All statistical analyses were performed with StatView 5.0 software (SAS Institute, Inc, Cary, NC).





Fig 1. Kaplan-Meier survival curve of all patients with surgical treatment of acute type A dissection in octogenarians and the number of patients (Pts) at risk.

Isolated medical management for AAD is ineffective and carries a high risk of aortic rupture [3, 25]. Mortality rates of medical management for AAD have been reported to reach 20% at 24 hours after presentation and may be as high as 50% at 1 month [26]. Trimarchi and associates [27] showed that medical management for octogenarians is rather widespread yet still associated with a higher in-hospital mortality rate than surgical management for AAD patients (55% vs 38%; p ¼ 0.188). Recently, first reports of successful cases of endovascular approaches for AAD have been introduced as less invasive alternative to open operations to reduce postoperative complications and mortality rates [6–9]. These technologies might be particularly appealing in elderly and high-risk patients. Different reports have demonstrated the feasibility and success of TEVAR for various ascending aortic pathologies, including AAD [28–31]. To date, however, this technique has various limitations because of the complex anatomic features of the ascending aorta and the aortic arch [7]. The application of this evolving technology within this delicate anatomic region has been limited due to proximity of the supraaortic vessels, anatomic curvature of the aorta, and unique flow dynamics in this vascular region. Furthermore, this technique depends on the pathologic pattern of the acute dissection and cannot be performed if the aortic valve and the coronary arteries are involved [32]. Currently, long-term follow-up data of TEVAR for this indication are missing, and it is too soon to draw any conclusions on the long-term durability, efficacy, and safety of this approach. Yet, TEVAR is rapidly evolving, and there is a great interest to expand its indications also to AAD. Similarly to the early days of transcatheter-based aortic valve implantation, innovative technologies are first being used in elderly high-risk patients unsuitable for routine operations. For this reason we believe that the time has come to gather data on surgical outcomes after treatment of AAD to set the bar for upcoming results after TEVAR for AAD in octogenarians.

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Until then, conventional operations with CPB will remain the gold standard to treat AAD by replacement of the dissected ascending aorta and the aortic arch, including the primary intimal tear. If total arch replacement is required, this is frequently accompanied by a higher incidence of morbidity and death compared with isolated ascending or hemiarch replacement alone [23, 33]. In 2012 we reported, in cooperation with colleagues from Bad Neustadt, a series of 1,002 patients in whom we found that the technique of selective ACP during moderate hypothermic circulatory arrest, according to the standardized surgical protocol applied in the two centers, was safe to manage complex aortic arch pathologies [10]. In the present study, the 30-day mortality was 26% (n ¼ 10) after emergency operations for AAD in octogenarians. This mortality rate can be considered good compared with the data presented from the German Registry for Acute Aortic Dissection Type A (GERAADA) and the International Registry of Aortic Dissection (IRAD) [25, 34]. These relatively good results may be partly attributable to our restrictive policy regarding the extent of aortic replacement in these elderly patients. This way, 82% of patients had hemiarch replacement only. Similarly, the aortic root it remained untouched in 23% of patients, could be glued and reconstructed in 56%, and replacement (bio-Bentall procedure) was only required in the remaining 21%. The incidence of postoperative neurologic complications after surgical treatment of AAD has been reported in the literature to be as low as 20% and as high as 37% [35–37]. A lower incidence of postoperative neurologic disorders was observed in our series, with TND occurring in 3 patients (8%) and PND in 2 (5%). The IRAD registry reported that more than 20% of patients with AAD are refused surgical repair because they are considered at high-risk for an open approach [25]. Our study demonstrates reasonable outcomes in a selected high-risk cohort of elderly patients. Furthermore, octogenarians who survive the initial emergency surgical intervention for AAD face an acceptable neurologic outcome and midterm survival. We conclude that facing the natural history of patients with untreated AAD, current data suggest a survival benefit with acute surgical intervention even in octogenarians. Comprehensive open surgical reference data are warranted to set the bar for upcoming reports of TEVAR for AAD in octogenarians.

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Surgical repair for acute type A aortic dissection in octogenarians.

Despite limited data, the necessity for immediate surgical intervention in octogenarians with acute type A aortic dissection (AAD) has recently been q...
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