Early and long-term results of surgery for aneurysms of the thoracic aorta in septuagenarians and octogenarians.

OBJECTIVE

The purpose of this study was to demonstrate early and long-term results of surgery for thoracic aortic aneurysm in patients over 70 years of age compared with those of patients under 70 years and to clarify the clinical problems peculiar to this subset of patients.

PATIENTS AND METHODS

Of 1157 patients who underwent surgery for thoracic aortic aneurysm from 1978 to December 1997, 261 who were 70 years or older were selected for analysis. Mean age at the time of surgery was 74.4 +/- 3.5 years. Aneurysms were atherosclerotic in 177 patients and aortic dissection in 84. Acute aortic dissection was found in 25 patients and ruptured aneurysm in 44. The control group consisted of 896 patients under 70 years. Preoperative complications such as AAA, peripheral arterial disease, emphysema, and old cerebral infraction were more common in the older group. Operative procedures consisted of replacement of the ascending aorta or hemiarch in 51 patients, total arch replacement in 75, distal arch replacement in 35, descending aorta replacement in 75, replacement of the thoracoabdominal aorta in 28, and extra-anatomical repair and others in 15. The technique of extracorporeal circulation was selective cerebral perfusion in 69 patients, deep hypothermic circulatory arrest in 90, femoro-femoral bypass in 39, left heart bypass in 12, and temporary aorto-arterial bypass in 30, and others in 21.

RESULT

Early mortality was 21% (54 patients), which was greater than that of the control group (113 patients, 13%, P < 0.01). The incidence of postoperative stroke, transient brain dysfunction, and respiratory problems was higher in the study group (P < 0.01 in all). Mean duration in ICU among survivors was 9.3 +/- 20.2 days and that of the control group was 5.9 +/- 2.8 days (P < 0.01). In a recent series (from 1991 to 1997) postoperative mortality improved to 15.6% (30/192 patients) in the study group however this result was still inferior to that of the control group (8.6%, 39/452, P = 0.03) however mortality of emergency surgery during the same periods was still high (31%, 11/35 patients). Logistic regression analysis revealed that significant risk factors for postoperative hospital death were surgery before 1991, age over 70 years, preoperative cardiac problems, aneurysm rupture, postoperative stroke, low output syndrome, bleeding, and acute renal failure. Postoperative follow-up was obtained in 408 patients/year and the longest period was 10.2 years. Late deaths were documented in 31 patients. Five-year and 10-year survival were 61.2 +/- 5.7% and 31.3 +/- 16.4%, respectively. In the control group the 5-year and 10-year survival were 78.0 +/- 2.1% and 62.5 +/- 4.0%, respectively (P = 0.03). However, survival of the early survivors in the study group was similar with that of the age-matched normal population. Aortic reoperation was performed in 13 patients. Freedom from aortic reoperation was 86.7 +/- 4.2% at 5 years and 80.5 +/- 7.1% at 10 years in the study group and 83.4 +/- 1.8% at 5 years and 64.1 +/- 13.3% at 10 years in the control group (P = 0.27).

CONCLUSION

Although recent advances have been achieved, early and long-term results of surgery for thoracic aortic aneurysm in patients older than 70 years were less satisfactory compared with those of patients under 70 years of age, especially in patients who required emergency surgery. Preoperative disorder of the vital organ systems was considered to be the main causative factor for high mortality, however, pertinent surgical strategies are necessary to improve the outcome of elderly patients.