European Journal of Cardio-Thoracic Surgery Advance Access published October 15, 2014
Acute type A aortic dissection: characteristics and outcomes comparing patients with bicuspid versus tricuspid aortic valve Christian D. Etza,†, Konstantin von Asperna,†*, Alexandro Hoyera, Felix F. Girrbachb, Sergey Leontyeva, Farhad Bakhtiarya, Martin Misfelda and Friedrich W. Mohra a b
Department of Cardiac Surgery, University of Leipzig, Heart Center Leipzig, Leipzig, Germany Department of Anaesthesiology and Intensive Care Medicine, University Hospital Leipzig, Leipzig, Germany
* Corresponding author. Department of Cardiac Surgery, Heart Center Leipzig, Struempellstrasse 39, 04289 Leipzig, Germany. Tel: +49-341-865251065; fax: +49-341-8652409; e-mail: [email protected] (K. von Aspern). Received 29 May 2014; received in revised form 30 August 2014; accepted 9 September 2014
Abstract OBJECTIVES: The aim of this study is to investigate the clinical characteristics and postoperative outcome of patients with a bicuspid aortic valve (BAV) suffering acute dissection in comparison with their tricuspid peers. METHODS: Between 1995 and 2011, 460 consecutive patients underwent emergency repair for acute type A aortic dissection. In 379 patients without connective tissue disease, the aortic valve morphology could clearly be specified (91.6% tricuspid and 8.4% bicuspid). RESULTS: At the time of dissection, patients with a bicuspid valve were younger (46.7 ± 13 vs 61.6 ± 12 years, P < 0.001) with the entry tear more often located in the root compared with those with a tricuspid valve (bicuspid: 31.3% vs tricuspid: 6.3%, P < 0.001). Consequently, surgical repair warranted root replacement in 93.8% of bicuspid vs 28.8% of tricuspid valve patients (P < 0.001). The leading pathology was medial necrosis/degeneration in bicuspid and atherosclerosis in tricuspid patients (P = 0.166). Hospital mortality was 20.3% and not significantly different between the two valve morphologies, even despite the younger age of bicuspid patients: 28.1% among bicuspids vs 19.6% among tricuspids (P = 0.255). Survival after discharge was 63.3% at 10 years for all patients. BAV patients had a significantly better survival with 100% at 10 years compared with 60.2% in tricuspid valve patients (P = 0.011). Mean follow-up among survivors was comparable for bicuspid and tricuspid patients (3.7 and 4.1 years, respectively). CONCLUSIONS: Patients with BAV have a distinctive dissection pattern with the entry tear frequently located in the aortic root and— despite their younger age—are subject to substantial hospital mortality. For bicuspid patients suffering from dissection, composite root replacement yields an excellent outcome equal to an age- and gender-matched normal population. Keywords: Acute aortic dissection • Stanford type A • Bicuspid aortic valve
INTRODUCTION A causative relationship between bicuspid aortic valve (BAV), the most common congenital abnormality of the heart affecting up to 2% in the general population, and acute type A aortic dissection (ADA) has been known for decades [1]. BAV predisposes to the development of ascending/root dilatation, which may be associated with dissection and rupture of the aorta, even in the absence of marked aortic valve dysfunction [2]. Flow architecture through the anomalous BAV has been suggested to impose abnormal local stress on the aortic wall responsible for an increased risk of dissection and aneurysm formation [3]. Bicuspid patients have also been proposed to exhibit a lower aortic distensibility and greater stiffness, both potentially increasing the risk of dissection, particularly during episodes of acutely elevated blood pressure [4]. Analyses on the large cohort of the International Registry of Acute Aortic Dissection (IRAD) suggest major clinical differences between †
The first two authors contributed equally to this study.
patients with tricuspid aortic valve (TAV) versus BAV [5]. These differences are emphasized in a recent observational study comparing patients with native TAV versus BAV suffering from acute type A dissection [6]. The authors found BAV patients to be younger, presenting more often with medial degeneration as an underlying pathology. This retrospective single-centre analysis focuses on the clinical characteristics, dissection pattern and outcome of patients with BAV in comparison with their tricuspid peers after ADA.
MATERIALS AND METHODS A review of the institutional database disclosed 460 consecutive patients who underwent emergent surgery for ADA from March 1995 to July 2011. Dissections were diagnosed preoperatively on the basis of contrast-enhanced computed tomography (CT) or echocardiography and were verified intraoperatively. Patients with congenital connective tissue disease (4%, N = 18;
© The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
AORTIC SURGERY
ORIGINAL ARTICLE
European Journal of Cardio-Thoracic Surgery (2014) 1–9 doi:10.1093/ejcts/ezu388
C.D. Etz et al. / European Journal of Cardio-Thoracic Surgery
2
Marfan = 15, Ehlers–Danlos-Disease type IV = 3, all TAV), iatrogenic dissection (10%, N = 48; TAV = 45, BAV = 3) and unknown valve morphology (3%, N = 15) were excluded from analysis to allow for non-confounded comparison with regard to short- and long-term outcomes. The remaining 379 patients (mean age: 60.3 ± 13, range: 23–85 years, male: 244) were used for analysis, of which 91.6% carried a TAV (TAV = 347, male = 221) and 8.4% a BAV (BAV = 32, male = 23). In the case of previous aortic valve replacement, valve morphology was classified according to previous OR reports. The maximum ascending aortic diameter was measured either intraoperatively or via preoperative CT, if applicable. The aortic valve morphology of bicuspid patients was not known prior to admission. The institutional review board approved this research; additional patient consent was not required.
Patient demographics and surgical technique The clinical characteristics and operative details are summarized in Tables 1 and 2.
Cannulation site and cerebral protection. In the majority of patients, arterial access for cardiopulmonary bypass (CPB) was established via the right axillary artery (N = 288, 76%). The femoral artery was used for cannulation in 20.1% (N = 76) and direct aortic cannulation in 4%. Patients in critical condition prior to surgery accounted for 17% of patients with antegrade perfusion (N = 51, axillary and direct aortic) and 11% with retrograde perfusion (N = 8, femoral). A total of 25 patients needed cardiopulmonary resuscitation before reaching the OR. Venous drainage was usually
Table 1: Patient characteristics Variable Clinical characteristics N (%) Number of patients Age (years, mean ± SD, CI) Male gender Risk factors History of hypertension Diabetes type 2 Smoker Hyperlipoproteinaemia Coronary artery disease Chronic haemodialysis COPD Aortic coarctation Pregnancy Previous aortic proceduresb Preoperative CPR Malperfusion Preoperative CVA (cerebral) Myocardial ischaemia (coronary) Visceral ischaemia (including renal) Extremity ischaemia (peripheral) Aortic pathology Aortic regurgitation (≥II°) +Aortic stenosis (≥II°) Isolated aortic stenosis (≥II°) Aorta ascendens diameterc (mm, mean ± SD, CI) Dissection characteristics Primary dissection entry verified Root Ascending aorta Aortic arch Descending aorta/not identified DeBakey classification Type I Type II Type III b retrograde Not classified Distal extension of dissection Ascending aorta Aortic arch Thoracic descending Abdominal aorta Unknown
All
TAV
BAV
P-value
379 (100) 60.3 ± 13 (58.9–61.7) 244 (64.4)
347 (91.6) 61.6 ± 12 (60.2–62.9) 221 (63.7)
32 (8.4) 46.7 ± 13 (42.2–51.2) 23 (71.9)
Acute type A aortic dissection: characteristics and outcomes comparing patients with bicuspid versus tricuspid aortic valve Christian D. Etza,†, Konstantin von Asperna,†*, Alexandro Hoyera, Felix F. Girrbachb, Sergey Leontyeva, Farhad Bakhtiarya, Martin Misfelda and Friedrich W. Mohra a b
Department of Cardiac Surgery, University of Leipzig, Heart Center Leipzig, Leipzig, Germany Department of Anaesthesiology and Intensive Care Medicine, University Hospital Leipzig, Leipzig, Germany
* Corresponding author. Department of Cardiac Surgery, Heart Center Leipzig, Struempellstrasse 39, 04289 Leipzig, Germany. Tel: +49-341-865251065; fax: +49-341-8652409; e-mail: [email protected] (K. von Aspern). Received 29 May 2014; received in revised form 30 August 2014; accepted 9 September 2014
Abstract OBJECTIVES: The aim of this study is to investigate the clinical characteristics and postoperative outcome of patients with a bicuspid aortic valve (BAV) suffering acute dissection in comparison with their tricuspid peers. METHODS: Between 1995 and 2011, 460 consecutive patients underwent emergency repair for acute type A aortic dissection. In 379 patients without connective tissue disease, the aortic valve morphology could clearly be specified (91.6% tricuspid and 8.4% bicuspid). RESULTS: At the time of dissection, patients with a bicuspid valve were younger (46.7 ± 13 vs 61.6 ± 12 years, P < 0.001) with the entry tear more often located in the root compared with those with a tricuspid valve (bicuspid: 31.3% vs tricuspid: 6.3%, P < 0.001). Consequently, surgical repair warranted root replacement in 93.8% of bicuspid vs 28.8% of tricuspid valve patients (P < 0.001). The leading pathology was medial necrosis/degeneration in bicuspid and atherosclerosis in tricuspid patients (P = 0.166). Hospital mortality was 20.3% and not significantly different between the two valve morphologies, even despite the younger age of bicuspid patients: 28.1% among bicuspids vs 19.6% among tricuspids (P = 0.255). Survival after discharge was 63.3% at 10 years for all patients. BAV patients had a significantly better survival with 100% at 10 years compared with 60.2% in tricuspid valve patients (P = 0.011). Mean follow-up among survivors was comparable for bicuspid and tricuspid patients (3.7 and 4.1 years, respectively). CONCLUSIONS: Patients with BAV have a distinctive dissection pattern with the entry tear frequently located in the aortic root and— despite their younger age—are subject to substantial hospital mortality. For bicuspid patients suffering from dissection, composite root replacement yields an excellent outcome equal to an age- and gender-matched normal population. Keywords: Acute aortic dissection • Stanford type A • Bicuspid aortic valve
INTRODUCTION A causative relationship between bicuspid aortic valve (BAV), the most common congenital abnormality of the heart affecting up to 2% in the general population, and acute type A aortic dissection (ADA) has been known for decades [1]. BAV predisposes to the development of ascending/root dilatation, which may be associated with dissection and rupture of the aorta, even in the absence of marked aortic valve dysfunction [2]. Flow architecture through the anomalous BAV has been suggested to impose abnormal local stress on the aortic wall responsible for an increased risk of dissection and aneurysm formation [3]. Bicuspid patients have also been proposed to exhibit a lower aortic distensibility and greater stiffness, both potentially increasing the risk of dissection, particularly during episodes of acutely elevated blood pressure [4]. Analyses on the large cohort of the International Registry of Acute Aortic Dissection (IRAD) suggest major clinical differences between †
The first two authors contributed equally to this study.
patients with tricuspid aortic valve (TAV) versus BAV [5]. These differences are emphasized in a recent observational study comparing patients with native TAV versus BAV suffering from acute type A dissection [6]. The authors found BAV patients to be younger, presenting more often with medial degeneration as an underlying pathology. This retrospective single-centre analysis focuses on the clinical characteristics, dissection pattern and outcome of patients with BAV in comparison with their tricuspid peers after ADA.
MATERIALS AND METHODS A review of the institutional database disclosed 460 consecutive patients who underwent emergent surgery for ADA from March 1995 to July 2011. Dissections were diagnosed preoperatively on the basis of contrast-enhanced computed tomography (CT) or echocardiography and were verified intraoperatively. Patients with congenital connective tissue disease (4%, N = 18;
© The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.
AORTIC SURGERY
ORIGINAL ARTICLE
European Journal of Cardio-Thoracic Surgery (2014) 1–9 doi:10.1093/ejcts/ezu388
C.D. Etz et al. / European Journal of Cardio-Thoracic Surgery
2
Marfan = 15, Ehlers–Danlos-Disease type IV = 3, all TAV), iatrogenic dissection (10%, N = 48; TAV = 45, BAV = 3) and unknown valve morphology (3%, N = 15) were excluded from analysis to allow for non-confounded comparison with regard to short- and long-term outcomes. The remaining 379 patients (mean age: 60.3 ± 13, range: 23–85 years, male: 244) were used for analysis, of which 91.6% carried a TAV (TAV = 347, male = 221) and 8.4% a BAV (BAV = 32, male = 23). In the case of previous aortic valve replacement, valve morphology was classified according to previous OR reports. The maximum ascending aortic diameter was measured either intraoperatively or via preoperative CT, if applicable. The aortic valve morphology of bicuspid patients was not known prior to admission. The institutional review board approved this research; additional patient consent was not required.
Patient demographics and surgical technique The clinical characteristics and operative details are summarized in Tables 1 and 2.
Cannulation site and cerebral protection. In the majority of patients, arterial access for cardiopulmonary bypass (CPB) was established via the right axillary artery (N = 288, 76%). The femoral artery was used for cannulation in 20.1% (N = 76) and direct aortic cannulation in 4%. Patients in critical condition prior to surgery accounted for 17% of patients with antegrade perfusion (N = 51, axillary and direct aortic) and 11% with retrograde perfusion (N = 8, femoral). A total of 25 patients needed cardiopulmonary resuscitation before reaching the OR. Venous drainage was usually
Table 1: Patient characteristics Variable Clinical characteristics N (%) Number of patients Age (years, mean ± SD, CI) Male gender Risk factors History of hypertension Diabetes type 2 Smoker Hyperlipoproteinaemia Coronary artery disease Chronic haemodialysis COPD Aortic coarctation Pregnancy Previous aortic proceduresb Preoperative CPR Malperfusion Preoperative CVA (cerebral) Myocardial ischaemia (coronary) Visceral ischaemia (including renal) Extremity ischaemia (peripheral) Aortic pathology Aortic regurgitation (≥II°) +Aortic stenosis (≥II°) Isolated aortic stenosis (≥II°) Aorta ascendens diameterc (mm, mean ± SD, CI) Dissection characteristics Primary dissection entry verified Root Ascending aorta Aortic arch Descending aorta/not identified DeBakey classification Type I Type II Type III b retrograde Not classified Distal extension of dissection Ascending aorta Aortic arch Thoracic descending Abdominal aorta Unknown
All
TAV
BAV
P-value
379 (100) 60.3 ± 13 (58.9–61.7) 244 (64.4)
347 (91.6) 61.6 ± 12 (60.2–62.9) 221 (63.7)
32 (8.4) 46.7 ± 13 (42.2–51.2) 23 (71.9)
