The increase in the lifespan of the western population

Outcome After Aortic Valve Replacement in Octogenarians Bruno Chiappini, MD, Nicola Camurri, MD, Antonio Loforte, MD, Luca Di Marco, MD, Roberto Di Bartolomeo, MD, and Giuseppe Marinelli, MD Department of Cardiovascular Surgery, University of Bologna, Bologna, Italy Background. The advancing age of the population in the western world and improvements in surgical techniques and postoperative care have resulted in an increasing number of very elderly patients undergoing cardiac operations. Therefore, the aim of this study is to evaluate the surgical outcome in 115 octogenarians after aortic valve replacement. Methods. We retrospectively identified 115 patients (47 men, 68 women) aged 82.3 2.1 years (mean, 80 to 92 years) who underwent aortic valve replacement alone (71 patients, 62.1%) or in combination with coronary artery bypass grafting (44 patients, 37.9%), between January 1992 and April 2003. These patients had significant severe aortic stenosis with a mean valve area of 0.62 0.15 cm 2 and a mean gradient of 88.62 24.06 mm Hg. Results. The in-hospital mortality rate was 8.5%. The late follow-up was 100% complete. Actuarial survival at 1 and 5 years was 86.4% and 69.4%, respectively. Predictors of late mortality were ejection fraction (p < 0.01), preoperative heart failure (p < 0.03), and the type of prosthesis (p < 0.03). Conclusions. The outcome after aortic valve replacement in octogenarians is excellent; the operative risk is acceptable and the late survival rate is good. Therefore, cardiac surgery should not be withheld on the basis of age alone. (Ann Thorac Surg 2004;78:85 9) 2004 by The Society of Thoracic Surgeons The increase in the lifespan of the western population in recent decades has resulted in a significant increase in the number of people more than 80 years of age referred to cardiac surgeons. Based on statistical studies, life expectancy varies from an average of approximately 8.1 years at the age of 80 years to 6 years at the age of 89 years [1]. Some studies have also shown that more than 25% of people who are 80 years or older suffer from a cardiovascular disease [2, 3]. In the Helsinki aging study [4], 17% of patients older than 80 years were observed to have severe aortic valve calcifications. In the cardiovascular health study [5] between 2% and 4% of individuals older than 75 years of age were noted to have severe aortic stenosis on echocardiography. Recent studies have shown that cardiac surgical procedures performed in elderly patients, in otherwise good physical and mental health, can improve the mortality, morbidity, and quality of life of those patients [6, 7 9]. However, results are still incomplete, especially for valve procedures. To analyze these issues, we have reviewed our early and long-term results in patients aged 80 years and older who underwent aortic valve replacement (AVR) alone or combined with coronary artery bypass grafting (CABG) for severe aortic stenosis. Accepted for publication Dec 19, 2003. Address reprint requests to Dr Chiappini, Department of Cardiovascular Surgery, Policlinico S. Orsola-Malpighi, Via Massarenti 3, 40138 Bologna, Italy; e-mail: bruno_chiappini@hotmail.com. Material and Methods Patients Between January 1982 and April 2003, 115 patients 80 years old or older underwent AVR with or without concomitant CABG at the Department of Cardiovascular Surgery of the University of Bologna. Our institutional review board approved this retrospective study. Follow-up information was obtained from all hospital survivors using a telephone interview and it was 100% complete. Mean follow-up time was 37.1 32.4 months (3 to 132 months). All known survivors were questioned to determine general health status, presence or absence of chest pain, angina pectoris, dyspnea, postoperative New York Heart Association (NYHA) functional class, and quality of life. Patient activity level was rated as heavy, defined as running or lifting heavy objects; moderate, defined as the ability to do housekeeping; light, defined as activities of daily living and bedridden. Operation was denied if the patient had severe renal failure, severe pulmonary failure, neurologic impairment, neoplasia, and poor general conditions. Urgent operations were defined as operative procedures performed on patients whose accelerated symptoms prompted urgent hospital admission for evaluation and who were judged to be unstable hemodynamically, needing surgical correction within 5 days. In-hospital mortality was considered to be any death occurring within 30 days after surgery. Perioperative myocardial infarction was defined as either a new Q wave or the elevation of the myocardial fraction of creatinine kinase 2004 by The Society of Thoracic Surgeons 0003-4975/04/$30.00 Published by Elsevier Inc doi:10.1016/j.athoracsur.2003.12.060

86 CHIAPPINI ET AL Ann Thorac Surg AORTIC VALVE REPLACEMENT IN OCTOGENARIANS 2004;78:85 9 in association with persistent ST segment changes. Stroke was defined as any neurologic deficit lasting longer than 24 hours. Postoperative renal failure was defined as an increase in serum creatinine of more than 2.0 g/dl. Carotid artery stenosis ( 70%), diagnosed by echo-color-doppler presented in 5 patients (5.2%) undergoing AVR and 2 undergoing AVR CABG. All procedures were carried out with cardiopulmonary bypass and at least mild systemic hypothermia (32 C). Cardiac arrest was achieved with cold crystalloid cardioplegia. All procedures were performed via the standard median sternotomy. The selection of the prosthesis type was left to the discretion of the operating surgeon and the preference of the patient. Coronary artery bypass grafting was performed whenever occlusive disease involved major epicardial vessels with a stenosis greater than 60%. Statistical Analysis Continuous variables were expressed as mean 1 standard deviation (SD) and were analyzed by using the unpaired two-tailed t test. Categorical variables were presented as percentages and were analyzed with the 2 test or Fischer s exact test when appropriate. All preoperative and intraoperative variables were first analyzed by using univariate analysis to determine whether any single factor influenced hospital mortality and clinical outcome; p less than 0.05 was considered to indicate statistical significance. Variables which achieved a p value of less than 0.05 in the univariate analysis were examined by using multivariate analysis with forward stepwise logistic regression to evaluate independent risk factors for hospital mortality, and neurologic, respiratory, and renal complications. Statistical analysis was performed with SPSS 8.0 statistical software (SPSS, Chicago, IL). Results The population consisted of 115 patients having a mean age of 82.3 2.1 years (min 80, max 92). The clinical characteristics of these patients are listed in Table 1. The most common presenting symptoms were dyspnea in 114 patients, congestive heart failure in 17, and angina in 89. Assessment of the left ventricular function showed that 24 (20.9%) patients had an ejection fraction (EF) of the left ventricle less than 50% (5 patients had an EF between 25% and 35%; 19 patients had an EF between 35% and 50%). The mean valve area was 0.62 0.15 cm 2 (0.32 to 0.98 cm 2 ) at transthoracic echocardiography; the mean maximum valve gradient was 88.61 24.06 mm Hg (40 to 151 mm Hg). Forty-four (37.9%) patients had significant coronary artery disease, requiring CABG (the mean number of bypasses was 1.7/patient). Details of the operative procedures are presented in Table 2. Biological prosthesis predominated and a stentless valve was implanted in 12 (10.3%) patients. Thirtynine percent of the patients more than 80 years received a mechanical prosthesis because of a narrowed aortic annulus or a concomitant atrial fibrillation. The inhospital mortality (30-day) rate was 8.5%. Seven patients Table 1. Clinical Characteristics of Study Population Characteristics Patients No./(%) Age (years) 82.3 2.1 Gender M 47 (40.86) F 68 (59.14) Hypertension 51 (44.9) Dislipidemia 27 (22.2) Diabetes 15 (13.8) Tobacco 11 (9.4) COPD 23 (19.8) TIA 5 (5.2) AF 18 (15.5) HF 17 (14.6) AMI 13 (12.1) Carotid artery stenosis 7 (6.1) Coronary artery atherosclerosis 44 (37.9) EF 50% 24 (20.9) PM 4 (3.4) NYHA I 1 (0.9) NYHA II 23 (19.8) NYHA III 78 (67.2) NYHA IV 13 (12.1) CCS I 26 (22.4) CCS II 51 (44) CCS III 27 (23.3) CCS IV 11 (10.4) AVA (cm 2 ) 0.62 0.15 AF atrial fibrillation; AMI acute myocardial infarction; AVA aortic valve area; CCS Canadian Cardiovascular Society; COPD chronic obstructive pulmonary disease; EF ejection fraction; HF heart failure; PM pacemaker; TIA transient ischemic attack. died from cardiac-related causes (n 4, myocardial infarction; n 3, cardiac failure). Noncardiac causes of death included pneumonia (n 2) and cerebrovascular accident (n 1). Table 3 shows the preoperative variables as predictors of in-hospital death. The mean EF 35% was the determining factor of in-hospital mortality. The length of stay in the intensive care unit was 3.72 days (1 to 57 days). There were no deaths among patients who Table 2. Operative Data Variables Patients No./(%) Elective 99 (85.3) Urgent 16 (14.7) CPBP time (min) 119.6 34.8 CC time (min) 90.03 24.06 Biological prosthesis 71 (61.2) Mechanical prosthesis 32 (27.5) Stentless prosthesis 12 (10.3) CABG AVR 44 (37.9) AVR 71 (62.1) Redo 2 (1.7) AVR aortic valve replacement; CABG coronary artery bypass graft; CC cross clamp; CPBP cardiopulmonary bypass.

Ann Thorac Surg CHIAPPINI ET AL 2004;78:85 9 AORTIC VALVE REPLACEMENT IN OCTOGENARIANS Table 3. Preoperative Predictors of In-Hospital Death at the Univariate Analysis Variable p Value Female gender EF Aortic valve area 0.03 Coronary artery disease Hypertension Hypercholesterolemia Diabetes Smoking history COPD Heart failure Respiratory failure (FEV1 60%) AF AMI Pacemaker Urgent operation Cross-clamp time 0.01 CABG Type of prosthesis AF atrial fibrillation; AMI acute myocardial infarction; CABG coronary artery bypass graft; COPD chronic obstructive pulmonary disease; EF ejection fraction; FEV functional expiratory volume at 1 second. remained hospitalized more than 30 days. The follow-up period was 100% complete and it was carried on by telephone interviews performed by well-trained doctors. The actuarial survival rate was 86.4% at 1 year and 69.4% at 5 years. The actuarial survival rate at 5 years, according to the type of prosthesis, was 81.7% in the bioprosthesis group, 56.7% in the mechanical group, and 66.7% in the stentless group (p 0.02) (Fig 1). These data suggest that the difference in the mortality rates among the three groups of patients is related to the type of prosthesis (bioprosthesis, mechanical, and stentless); the Fig 2. The survival curves according to whether or not concomitant coronary artery bypass grafting (CABG) had been carried out. ( no CABG; Πyes CABG.) mechanical group had a higher mortality rate because of the increased risk of thromboembolic and hemorrhagic events due to the anticoagulant therapy; in the stentless group, 41.6% of the patients underwent a concomitant CABG. Analyzing the survival curves according to whether or not concomitant CABG had been carried out, we found that it was 76.1% in the patients who died and who had not undergone CABG and 68.2% in those patients who had undergone CABG without any significant statistical difference (p 0.7) (Fig 2). Stepwise logistic regression analysis revealed a preoperative ejection fraction (p 0.008), preoperative heart failure (p 0.03), and type of implanted prosthesis (p 0.03) as predictors of late death. Twenty-one (22.1%) patients died: 16 (76.1%) patients from cardiovascular causes and 5 (23.8%) patients from noncardiac causes (n 4 neoplasia, n 1 respiratory failure). Eighty-four long-term survivors responded to telephone interviews regarding their functional status and quality of life. The mean NYHA functional class improved from 2.90 0.6 to 1.6 plusmn; 0.6, with 80 patients (94.1%) in class I or II (p 0.01). Patients rated their activity level as heavy (56.3%) or moderate (44.7%). Among patients who underwent a mechanical prosthesis implantation, 4 (22.2%) experienced valve-related complications, such as thromboembolism (n 2 patients) and bleeding events (n 2 patients), but they did not experience prosthetic valve endocarditis or reoperations. 87 Fig 1. The actuarial survival rates according to the type of prosthesis. Πbioprosthesis; mechanical. Comment The incidence of cardiovascular disease is as high as 40% and it is the leading cause of death among the elderly [10]. Furthermore, these patients often have concomitant diseases, such as renal insufficiency, chronic obstructive pulmonary disease, peripheral vascular disease, prostatic enlargement complicated by urinary retention, and de-

88 CHIAPPINI ET AL Ann Thorac Surg AORTIC VALVE REPLACEMENT IN OCTOGENARIANS 2004;78:85 9 generative cerebral disease [11, 12]. Therefore, despite these comorbidities, the demand for cardiac operations in elderly patients has increased over the last 10 years. Ten years ago, cardiac operations in patients aged 80 years and older were relatively uncommon [13]. Since then, there has been a marked increase in the number of operations performed in this age group. The decision for surgery is complex in this group of patients and we usually take into account several elements, such as the lack of synchronism between physiologic age and chronologic age, the quality of life, and the risk-benefit ratio. This paper, analyzing the postoperative and long-term outcome of 115 octogenarians undergoing aortic valve replacement, is a contribution to aid in the decision-making process,. The main surgical indications at our Institution were the aortic valve area (AVA) less than 1 cm 2 and the onset of symptoms. The contraindications to refuse surgery were: the deficit of the other organs (kidneys, liver, and lungs); an EF less than 25%; a severely calcified ascending aorta; severe coronary artery disease with no indication for surgery; and refusal of surgery by the patient and his relatives. In this study, we defined the risk factors that would be predictors of early death in this elderly population and we identified them by univariate analysis. Emergency admission in the very elderly has been shown to be an independent predictor of early mortality [14]. Our study supports this finding as all early deaths occurred in patients whose admission was classified as urgent. These results suggest that elderly patients should be referred for operation as early as possible to prevent urgent operations or advanced stage disease. Urgent surgery has also been predictive of late mortality in other recent studies [14]. The cumulative survival rate was 73% after a mean follow-up time of 37.1 32.4 months. This survival rate is comparable with other studies and shows good longterm survival despite advanced age [15 17]. In our patients, we implanted 32 mechanical, 71 biological, and 12 stentless valves. We believe that the bioprosthetic valve is the safest cardiac valve substitute for octogenarians. Because systemic anticoagulation is rarely required for a long period, bioprosthetic valves have a reduced incidence of bleeding and thrombotic complications as compared to mechanical valves; actually, the patients stopped warfarin intake three months after surgery, switching to 100 mg/ die of aspirin [18]. In effect, in the study population in our series, the episodes of thromboembolism and hemorrhage occurred in patients who had received a mechanical prosthesis. Furthermore, at survival analysis, we found a statistically significant difference among patients undergoing AVR with a mechanical prosthesis (56.7%) and those receiving a bioprosthesis (81.7%), (log rank, p 0.02). Actually, our policy about the choice of patients is very strict; we prefer to implant the tissue valve in this particular population because we believe the balance risk-benefit is absolutely favorable to biological prosthesis. The indication for implanting a stentless prosthesis Table 4. Postoperative Complications Variable n (%) AF 20 (17.3) Mechanical ventilation 24 hours 6 (5.2) Stroke 1 (0.8) Atrioventricular block (pacemaker) 4 (3.4) Low cardiac output 1 (0.8) AMI 4 (3.8) AF atrial fibrillation; exists in patients with a narrowed annulus without a severely calcified aorta, provided that the ejection fraction and the functional status of the other organs are good and if the lifestyle of the patient is active, requiring a prosthesis with the better hemodynamic performance. In patients with a narrowed annulus, impaired organ function, and atrial fibrillation, we prefer to use a mechanical prosthesis to simplify the surgical act and to shorten the operating time. The perioperative stroke rate is very low (Table 4). This is very interesting because the incidence of stroke after cardiac surgery can be up to 2% of the elderly population without carotid stenosis; but in our study it is 0.8%, which is comparable to that of the younger population. In this type of patient, we avoided manipulating the aorta and we used the atraumatic aortic clamp. We evaluated the patients perception of their activity status as well and we found that 98% of the patients who underwent AVR were satisfied with their choice. In terms of functional status, we found that there was a statistically significant improvement of the NYHA class at follow-up in comparison to the preoperative class (2.9 0.6 vs1.6 0.6, p 0.01). According to our results and those in the literature concerning elective surgery for aortic valve stenosis, the indications for surgery could be extended (ie, in patients with AVA 1.2 to 1.4 cm 2 ), because the clinical history of degenerative aortic stenosis in the elderly has a faster evolution than that of rheumatic aortic valve stenosis and because urgent surgery is the most severe risk factor for death. In summary, we believe that octogenarians with aortic valve disease should not be denied the benefits of surgery if they are reasonably good surgical candidates, are physically and mentally able to stand the stress of surgery, and are motivated to improve their lifestyle. Cardiac surgery can be performed in patients more than 80 years old giving good long-term results, an acceptable mortality, and a good quality of life especially if the indication for surgery is early thus avoiding delays and the risk of impairment of the left ventricular function Table 4. References AMI acute myocardial infarction. 1. Statistical. Abstract of the United States/1991 (111th Ed); Washington DC: Department of Commerce, US Bureau of the Census, 1991:81.

Ann Thorac Surg CHIAPPINI ET AL 2004;78:85 9 AORTIC VALVE REPLACEMENT IN OCTOGENARIANS 2. National Center for Health Statistics. Vital statistics of the United States, 1989: Vital health statistics: vol 2. Washington DC: US Goverment Printing Office. 3. National Center for Health Statistics. Current estimates from the National Health Interview Survey, 1989: Vital health statistics, series 10. Washington DC: US Government Printing Office, 1990:176. 4. Lindroos M, Kupari M, Heikkila J, Tilvis R. Prevalence of aortic valve abnormalities in the elderly: an echocardiographic study of a random population sample. J Am Coll Cardiol 1993;21:d5 1220. 5. Stewart BF, Siscovick D, Lind BK, et al. Clinical factors associated with calcific aortic valve disease. J Am Coll Cardiol 1997;29:630 634. 6. Tsai TP, Nessim S, Kass RM, et al. Morbidity and mortality after coronary artery bypass in octogenarians. Ann Thorac Surg 1991;51:983 6. 7. Culliford AT, Galloway AC, Colvin S, et al. Aortic valve replacement for aortic stenosis in patients aged 80 years and over. Am J Cardiol 1991;67:1256 60. 8. Kleikamp G, Minami K, Breymann T, et al. Aortic valve replacement in octogenarians. J Heart Valve Dis 1992;1:196 200. 9. Statistical. Abstract of the United States/1994 (114th ed.); Washington DC: Department of Commerce, US Bureau of the Census, 1994:84. 10. Edmunds LHJ, Stephenson LW, Edie RN, Ratcliffe MB. Open-heart surgery in octogenarians. N Engl J Med 1988; 319:131 6. 11. Craver JM, Goldstein J, Jones EL, Knapp WA, Hatcher CRJ. Clinical, hemodynamic, and operative descriptors affecting outcome of aortic valve replacement in elderly versus young patients. Ann Surg 1984;199:733 41. 12. The United Kingdom Heart Valve Registry Report 2000. A UK Heart Registry Publication 2002. 13. Akins CW, Daggett WM, Vlahakes GJ, et al. Cardiac operation in patients 80 years old and older. Ann Thorac Surg 1997;64:606 15. 14. Chocron S, Etievent JP, Viel JF, et al. Aortic valve replacement in the elderly: a comparative assay of potential risk factor modification. J Heart Valve Dis 1995;4:268 73. 15. Elayada MA, Hall RJ, Reul RM, et al. Aortic valve replacement in patients 80 years and older: operative risks and long-term results. Circulation 1993;88:11 6. 16. Straumann E, Kiowski W, Langer I, et al. Aortic valve replacement in elderly patients with aortic stenosis. Br Heart J 1994;71:449 53. 17. Borkon AM, Soule LM, Baughman KL, et al. Aortic valve selection in the elderly patient. Ann Thorac Surg 1988;46:270 7. 89 Internet Discussion Forum Each month, we select an article from The Annals of Thoracic Surgery for discussion within the Surgeon s Forum of the CTSNet Discussion Forum Section. The articles chosen rotate among the six dilemma topics covered under the Surgeon s Forum, which include: General Thoracic Surgery, Adult Cardiac Surgery, Pediatric Cardiac Surgery, Cardiac Transplantation, Lung Transplantation, and Aortic and Vascular Surgery. Once the article selected for discussion is published in the online version of The Annals, we will post a notice on the CTSNet home page (http://www.ctsnet.org) with a FREE LINK to the full-text article. Readers wishing to comment can post their own commentary in the discussion forum for that article, which will be informally moderated by The Annals Internet Editor. We encourage all surgeons to participate in this interesting exchange and to avail themselves of the other valuable features of the CTSNet Discussion Forum and Web site. For July, the article chosen for discussion under the Adult Cardiac Surgery Dilemma Section of the Discussion Forum is: Trainees Operating on High-Risk Patients Without Cardiopulmonary Bypass: A High-Risk Strategy? Raimondo Ascione, MD, Barnaby C. Reeves, PhD, Marco Pano, MD, and Gianni D. Angelini, FRCS Tom R. Karl, MD The Annals Internet Editor UCSF Children s Hospital Pediatric Cardiac Surgical Unit 505 Parnassus Ave, Room S-549 San Francisco, CA 94143-0118 Phone: (415) 476-3501 Fax: (212) 202-3622 e-mail: karlt@surgery.ucsf.edu 2004 by The Society of Thoracic Surgeons Ann Thorac Surg 2004;78:89 0003-4975/04/$30.00 Published by Elsevier Inc