Motomi Ando

Prospective comparative study of brain protection in total aortic arch replacement: deep hypothermic circulatory arrest with retrograde cerebral perfusion or selective antegrade cerebral perfusion

BACKGROUND The purpose of this study was to compare the results of total aortic arch replacement using two different methods of brain protection, particularly with respect to neurologic outcome. METHODS From June 1997, 60 consecutive patients who underwent total arch replacement through a midsternotomy were alternately allocated to one of two methods of brain protection: deep hypothermic circulatory arrest with retrograde cerebral perfusion (RCP: 30 patients) or with selective antegrade cerebral perfusion (SCP: 30 patients). Preoperative and postoperative (3 weeks) brain CT scan, neurological examination, and cognitive function tests were performed. Serum 100b protein was assayed before and after the cardiopulmonary bypass, as well as 24 hours and 48 hours after the operation. RESULTS Hospital mortality occurred in 2 patients in the RCP group (6.6%) and 2 in the SCP group (6.6%). New strokes occurred in 1 (3.3%) of the RCP group and in 2 (6.6%) of the SCP group (p = 0.6). The incidence of transient brain dysfunction was significantly higher in the RCP group than in the SCP group (10, 33.3% vs 4, 13.3%, p = 0.05). Except in patients with strokes, S-100b values showed no significant differences in the two groups (RCP: SCP, prebypass 0.01+/-0.04: 0.05+/-0.16, postbypass 2.17+/-0.94: 1.97+/-1.00, 24 hours 0.61+/-0.36: 0.60+/-0.37, 48 hours 0.36+/-0.45: 0.46+/-0.40 microg/L, p = 0.7). There were no intergroup differences in the scores of memory decline (RCP 0.74+/-0.99; SCP 0.55+/-1.19, p = 0.6), orientation (RCP 1.11+/-1.29; SCP 0.50+/-0.76, p = 0.08), or intellectual function (RCP 1.21+/-1.27; SCP 1.05+/-1.15, p = 0.7). CONCLUSIONS Both methods of brain protection for patients undergoing total arch replacement resulted in acceptable levels of mortality and morbidity. However, the prevalence of transient brain dysfunction was significantly higher in patients with the RCP.

Mortality And Cerebral Outcome In Patients Who Underwent Aortic Arch Operations Using Deep Hypothermic Circulatory Arrest With Retrograde Cerebral Perfusion: No Relation Of Early Death, Stroke, And Delirium To The Duration Of Circulatory Arrest

OBJECTIVE Our goal was to investigate factors for mortality and cerebral outcome in patients with aneurysm of the aortic arch. METHODS From 1993 to 1996, 148 patients with aortic arch aneurysm underwent operations involving deep hypothermic circulatory arrest with retrograde cerebral perfusion. Age was 63.9 +/- 11.6 years (mean +/- standard deviation) and 52 patients were older than 70 years. Twenty-eight had acute aortic dissection. Twelve had ruptured aneurysms. Fourteen had redo operations. Seventy had aortic dissection. The aneurysms were caused by atherosclerosis in 123 patients and by other causes in 25. Median sternotomy was used in 92 and left thoracotomy in 56. Twenty-eight patients underwent replacement of the ascending aorta to the proximal arch, 62 had total arch replacement, 38 had distal arch replacement, 12 had simultaneous replacement of the distal arch and the descending aorta or thoracoabdominal aorta, and 8 had patch repair. RESULTS Fifteen (10.1%) early deaths occurred. New stroke occurred in six (4.0%) patients and transient delirium in 37 (25.0%). The duration of deep hypothermic circulatory arrest plus retrograde cerebral perfusion was 49 +/- 17 minutes, and it was more than 60 minutes in 36 patients. Patients awoke 7.5 +/- 8.2 hours after the operation. Logistic regression analysis demonstrated that risk factors for mortality were ruptured aneurysm, chronic obstructive pulmonary disease, arterial cannulation in the ascending aorta, and stroke. Risks for stroke were ruptured aneurysm and replacement of the distal arch. Risks for delirium were age older than 70 years and atherosclerotic aneurysm. Duration of circulatory arrest plus cerebral perfusion did not correlate with length of time before the patient regained consciousness. No difference was found in mortality, stroke, and delirium between patients with and those without more than 60 minutes of circulatory arrest and cerebral perfusion. CONCLUSION Prolonged (> 60 minutes) deep hypothermic circulatory arrest with retrograde cerebral perfusion was not a risk factor for mortality and stroke in patients who underwent surgery for aneurysms of the aortic arch. However, the prevalence of transient delirium necessitates further investigations.

Percutaneous Transluminal Pulmonary Angioplasty for the Treatment of Chronic Thromboembolic Pulmonary Hypertension

Background—Chronic thromboembolic pulmonary hypertension leads to pulmonary hypertension and right-sided heart failure. The purpose of this study was to investigate the efficacy of percutaneous transluminal pulmonary angioplasty (PTPA) for the treatment of chronic thromboembolic pulmonary hypertension. Methods and Results—Twenty-nine patients with chronic thromboembolic pulmonary hypertension underwent PTPA. One patient had a wiring perforation as a complication of PTPA and died 2 days after the procedure. In the remaining 28 patients, PTPA did not produce immediate hemodynamic improvement at the time of the procedure. However, after follow-up (6.0 ± 6.9 months), New York Heart Association functional classifications and levels of plasma B-type natriuretic peptide significantly improved (both P<0.01). Hemodynamic parameters also significantly improved (mean pulmonary arterial pressure, 45.3 ± 9.8 versus 31.8 ± 10.0 mm Hg; cardiac output, 3.6 ± 1.2 versus 4.6 ± 1.7 L/min, baseline versus follow-up, respectively; both P<0.01). Twenty-seven of 51 procedures in total (53%), and 19 of 28 first procedures (68%), had reperfusion pulmonary edema as the chief complication. Patients with severe clinical signs and/or severe hemodynamics at baseline had a high risk of reperfusion pulmonary edema. Conclusions—PTPA improved subjective symptoms and objective variables, including pulmonary hemodynamics. PTPA may be a promising therapeutic strategy for the treatment of chronic thromboembolic pulmonary hypertension. Clinical Trial Registration—URL: http://www.umin.ac.jp. Unique identifier: UMIN000001572.

Total arch replacement using antegrade selective cerebral perfusion with right axillary artery perfusion

OBJECTIVE Right axillary artery (AxA) perfusion, which can prevent cerebral embolism caused by retrograde perfusion via the femoral artery (FA), was used for selective cerebral perfusion (SCP) as well as cardiopulmonary bypass (CPB) in aortic arch repair. We review the outcome of aortic arch surgery using SCP with right AxA perfusion to clarify its efficacy. METHOD Between 1998 and 2002, 120 patients underwent aortic arch repair using SCP with right AxA perfusion. The mean age was 69+/-10 years. Aneurysms were atherosclerotic in 79, dissecting in 32, and others in nine patients. Twenty of them (16.7%) required emergency surgery. CPB was initiated with right AxA and FA perfusion, and following SCP was established using right AxA and left common carotid artery perfusion. RESULTS With right AxA perfusion, hospital mortality was 5.8%. Multivariate analysis showed only ruptured aneurysm was an independent determinant for hospital mortality. Permanent neurological dysfunction developed in one patient (0.8%), while seven (5.8%) suffered from temporary one. In univariate analysis, SCP time, stenosis of the carotid arteries, past history of cerebrovascular events, and atherosclerotic aneurysm were not related to temporary neurological deficits CONCLUSION Right AxA perfusion in conjunction with SCP is a safe and useful alternative for brain protection in total arch replacement.

Plasma brain natriuretic peptide as a noninvasive marker for efficacy of pulmonary thromboendarterectomy

BACKGROUND Plasma brain natriuretic peptide (BNP), a cardiac hormone secreted mainly by the cardiac ventricles, has been shown to increase in proportion to the degree of cardiac overload. However, whether plasma BNP may serve as a marker for the efficacy of pulmonary thromboendarterectomy in patients with chronic thromboembolic pulmonary hypertension remains unknown. METHODS Plasma BNP level was measured in 34 patients with chronic thromboembolic pulmonary hypertension before and 1 month after pulmonary thromboendarterectomy. Right heart catheterization was also performed before and 1 month after the operation. RESULTS Preoperative plasma BNP level was significantly elevated in patients with chronic thromboembolic pulmonary hypertension compared with control patients (246 +/- 40 vs 13 +/- 2 pg/mL; p < 0.001; n = 34) and was positively correlated with total pulmonary resistance (r = 0.57; p < 0.001). After pulmonary thromboendarterectomy, plasma BNP level in survivors markedly decreased (220 +/- 31 to 54 +/- 9 pg/mL; p < 0.001; n = 32) in association with a reduction of total pulmonary resistance (15.6 +/- 1.0 to 4.5 +/- 0.3 Wood units; p < 0.001). The change in plasma BNP level was closely correlated with that in total pulmonary resistance (r = 0.63; p < 0.001). Importantly, a sustained elevation of plasma BNP (> or = 50 pg/mL) indicated the presence of residual pulmonary hypertension (> or = 5 Wood units) after operation (sensitivity = 73%; specificity = 81%). CONCLUSIONS Plasma BNP level was strongly associated with the severity of pulmonary hypertension in patients with chronic thromboembolic pulmonary hypertension and thereby may serve as a noninvasive marker for the efficacy of pulmonary thromboendarterectomy.

Predictive Factors for Mortality and Cerebral Complications in Arteriosclerotic Aneurysm of the Aortic Arch

BACKGROUND The incidence of cerebral complications is high in patients with aortic arch aneurysm. METHODS Between December 1977 and December 1995, 246 patients with arteriosclerotic arch aneurysm underwent operation. Thirty-nine patients had an aneurysm involving the entire arch, 193 had only distal arch aneurysm, and 14 had arch aneurysm extending to the descending aorta. Eighty-seven patients underwent replacement of the total arch, 85 had replacement of only the distal arch, 14 had simultaneous replacement of the descending aorta, 45 had patch repair, and 15 had thromboexclusion. Selective cerebral perfusion was used in 112 patients and partial bypass in 58 in the earlier series of patients, but deep hypothermic circulatory arrest with retrograde cerebral perfusion technique was exclusively applied in the most recent 76 patients. RESULTS There were 50 (20%) early deaths and 37 (19%) late deaths. Postoperative stroke was found in 26 (11%) patients of which 13 (50%) died. Mutual predictive factors for postoperative mortality and stroke were earlier series, preoperative chronic renal failure, ruptured aneurysm, arch clamping during procedure, and using partial cardiopulmonary bypass. Among 129 patients operated on during the most recent 5 years, early mortality and incidence of stroke decreased to 14.7% and 6.9%, respectively. CONCLUSIONS Results of operations for arteriosclerotic aneurysms of the transverse aortic arch in 246 patients during a period of 17 years have been improving but are still not satisfactory.

Simultaneous graft replacement of the ascending aorta and total aortic arch for type A aortic dissection

We performed simultaneous graft replacement of the total aortic arch and ascending aorta for type A aortic dissection with a patent false lumen extending through the arch into the descending or abdominal aorta. During the past 7 years, this procedure was performed in 42 patients (28 men and 14 women), aged 20 to 72 years (mean age, 50 years). Nineteen patients underwent the procedure during the acute period, and 23 during the chronic period. The site of the initial intimal tear was the ascending aorta in 17 patients and the transverse aortic arch in 25 patients. Artificial graft replacement was initially accomplished by proximal anastomosis, followed by open distal anastomosis, and finally by anastomosis of each of the three arch vessels. There were 3 hospital deaths (7.1%), 1 resulting from acute dissection (5.3%) and 2 from chronic dissection (8.7%). Among the type A dissections, total arch graft replacement has been indicated in the setting of rupture of the aortic arch, arch dissection, and Marfans syndrome. However, with increasing experience in arch reconstructions and improvement in outcome, the indications could be expanded to include all type A aortic dissections with a patent false lumen in the descending aorta.

Preoperative demonstration of the Adamkiewicz artery by magnetic resonance angiography in patients with descending or thoracoabdominal aortic aneurysms

OBJECTIVE Investigating the possibility of magnetic resonance angiography (MRA) to visualize the Adamkiewicz artery of as a preoperative study of thoracic aortic aneurysms. METHODS From February 1998 to March 1999, 26 consecutive patients who had aneurysms of the thoracoabdominal or descending aorta underwent preoperative MRA to visualize the Adamkiewicz artery. Mean age was 60.5+/-11.5 years. Fifteen patients had non-dissecting aneurysm and 11 had aortic dissections. Nineteen patients underwent replacement of the aneurysms, four patients underwent endovascular stent-graft repair, and three patients were discharged without treatment of aneurysm. MRA was performed on a 1.5-T system (Magnetom, Siemens) and data acquisition was repeated two times following injection of gadolinium-DTPA. Source images were reconstructed with multiplanar reconstruction and maximum intensity projection. Criteria for the Adamkiewicz artery of were that the artery ascends from the dorsal branch of the intercostal or lumbar artery to the anterior mid-sagital surface of the spinal cord in the early phase. RESULTS The Adamkiewicz arteries were demonstrated in 18 patients (69%). These arteries were originated from the left intercostal or lumbar arteries in 13 (72.2%) patients and from the right in 5 (27.8%) and from the Th8 branch in three, Th9 in seven, Th10 in two, Th11 in four, and L1 in two. All patients had graft replacement of the aorta using a partial bypass. All intercostal or lumber arteries, which were visualized as the origin of the Adamkiewicz artery, were reattached to the grafts. No spinal cord injury occurred. CONCLUSION Preoperative detection the Adamkiewicz artery was possible by MRA and was very useful to reduce the incidence of ischemic injury of the spinal cord during surgery of the thoracoabdominal or descending aorta.

Evolving arch surgery using integrated antegrade selective cerebral perfusion: impact of axillary artery perfusion.

OBJECTIVE The study objective was to determine the impact of integrated antegrade selective cerebral perfusion with right axillary artery perfusion during arch surgery. METHODS All surgeries were performed through a median sternotomy. Direct cannulation of the right axillary artery in the axilla was used for cardiopulmonary bypass and antegrade selective cerebral perfusion under hypothermia. In addition, ascending aortic or femoral artery perfusion was used. The clinical records of 531 patients (median age, 72 years) between 1999 and 2006 were reviewed, of whom 137 patients (25.8%) underwent emergency surgery. There were 164 dissecting and 367 nondissecting aortic lesions. The surgeries included total arch replacement in 431 patients, partial arch replacement in 9 patients, and hemiarch replacement in 91 patients. RESULTS The early mortality rate was 4.0% (2.3% of 30-day mortality and 1.7% of in-hospital mortality). The incidence of permanent neurologic dysfunction was 2.9% in all (3.3% in total arch replacement and 1.0% in hemiarch or partial arch replacement). The incidence of temporary dysfunction was 9.9% in all (10.6% in total arch replacement and 7.0% in hemiarch or partial arch replacement). Multivariate analysis demonstrated that the risk factors for early mortality were chronic renal failure, ruptured nondissecting aneurysm, and prolonged surgery. The midterm survival was 87.2% +/- 1.7% at 3 years and 80.5% +/- 2.6% at 5 years. CONCLUSION Right axillary artery perfusion is an advantageous adjunct to cardiopulmonary bypass and antegrade selective cerebral perfusion in arch surgery.

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.