Tetsuro Morota

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.

Left ventricular mechanical support with Impella provides more ventricular unloading in heart failure than extracorporeal membrane oxygenation.

The Impella microaxial-flow pump can directly unload left ventricle (LV) in cases of acute heart failure. Extracorporeal membrane oxygenation (ECMO) is widely used for circulatory support. Although the clinical effectiveness of ECMO has been demonstrated, insufficient LV loading reduction may not be advantageous for myocardial recovery. The objective was to compare ventricular loading reduction and reversibility of ventricular fibrillation (VF) with either Impella or ECMO. Six dogs were used. Extracorporeal membrane oxygenation was established by the femoral artery and right atrium. The Impella LD was inserted in LV by the ascending aorta. An acute failing heart was created by sequential coronary artery ligations. Pressure–volume (PV) relationships were acquired without a device and with ECMO or Impella. When VF occurred, direct cardioversion was performed while supported by either ECMO or Impella. The PV area, which is a measure of ventricular unloading and is correlated with myocardial oxygen consumption, decreased more with Impella than with ECMO. Successful defibrillation was achieved more effectively while under Impella support. Superior ventricular unloading with the Impella device may provide higher recovery potential to damaged hearts than ECMO and may have a significant impact not only on intensive care of patients with heart failure but also on resuscitation.

Elephant trunk procedure for surgical treatment of aortic dissection

BACKGROUND In surgical intervention for aortic dissection, a highly radical operation can be performed by distal anastomosis with a true lumen resulting in thrombotic closure of the dissecting lumen. In this anastomosis, the elephant trunk procedure, in which a graft is inserted into the distal true lumen, prevents blood flow leakage into the dissecting lumen at the anastomosis site and also strengthens this area. METHODS We performed this procedure in 15 patients (8 men and 7 women). Acute aortic dissection was observed in 9 patients and chronic dissection in 6. Stanford type A dissection was diagnosed in 10 patients and type B in 5. RESULTS Graft replacement of the ascending aorta and total aortic arch was performed in 10 patients and descending aortic replacement in 5. A graft with a diameter of 16 to 24 mm was inserted into the true lumen of the descending aorta, and the false lumen was closed. Subsequently, distal anastomosis was performed on the true lumen. There were two hospital deaths. Postoperative digital subtraction angiography showed good results in living patients, and computed tomographic scanning showed thrombotic closure in the dissecting lumen of the descending aorta. CONCLUSIONS The elephant trunk procedure is useful for closing the false lumen of the distal aorta.

Open stent-grafting for aortic arch aneurysm is associated with increased risk of paraplegia

BACKGROUND Open surgery using the endovascular stent-graft is a novel technique that lessens the invasiveness of surgery for the aortic arch. However, the outcome of this procedure remains uncertain. METHODS Between November 1996 and July 2000, a total of 19 patients underwent open surgery using an endovascular stent-graft for thoracic aortic aneurysms. There were 15 men (78.9%) and 4 women (21.1%). Patient age ranged from 29 to 82 years (mean 69.3 years, median 74 years). Atherosclerotic thoracic aortic aneurysms were present in 17 patients (89.4%) and aortic dissection in 2 patients (10.5%). RESULTS Two patients (10.5%) died in the hospital and 4 patients (21.1%) presented with paraplegia postoperatively. Among the 4 patients with postoperative paraplegia, 1 case was complicated with intraoperative aortic dissection. The other 3 patients with paraplegia had spinal cord ischemic time of more than 60 minutes and intraoperative body weight gain of more than 4 kg. Of these 3 patients, hemodynamic instability after cardiopulmonary bypass was observed in 1 patient and cholesterin embolus in the anterior spinal artery was found at autopsy in another. On univariate analysis, age greater than 75 years was the only risk factor associated with paraplegia (p < 0.05). Autopsy findings for the 2 patients showed that the Adamkiewicz arteries were not blocked by the stent-graft in either patient. CONCLUSIONS Intraoperative aortic dissection, embolization of the intercostal arteries, long ischemic time of the spinal cord, and excessive weight gain during operation may have been associated with the high incidence of paraplegia after open surgery using the endovascular stent-graft.

Predictive factors for postoperative cerebral complications in patients with thoracic aortic aneurysm

OBJECTIVE Perioperative factors affecting the outcomes of postoperative brain function in patients with thoracic aortic aneurysm were demonstrated. PATIENTS AND METHODS From December 1977 to September 1994, 745 patients with thoracic aortic aneurysm underwent 846 operations. The mean age at surgery was 57.1 +/- 14.2 years old. Four hundred seventy-four patients had true aneurysm and 372 had aortic dissection. Two hundred forty-four patients underwent repair in the ascending aorta, 189 arch repair, 242 repair in the descending aorta. 79 replacement of the thoracoabdominal aorta, and 92 extra-anatomical bypass or thrombo-exclusion of the aorta. Conventional cardiopulmonary bypass was used in 297 patients, partial cardiopulmonary bypass through femoral access in 167, selective cerebral perfusion in 253, deep hypothermic circulatory arrest and retrograde cerebral perfusion in 50, temporary shunt in 29, and no circulatory support was applied in 50. Postoperative cerebral complications were divided into permanent cerebral dysfunction. RESULTS The early mortality rate was 15.5% (131 patients). Incremental risk factors for hospital mortality were non-preexisting cardiac lesions, ruptured aneurysm, postoperative cerebral complications, sepsis, bleeding, low output syndrome and renal failure. Cerebral complications occurred in 81 patients (9.6%), involving 47 permanent and 34 transient sequelae. The early mortality rate in patients with postoperative brain damage was 42.0%. The etiologies of the brain damage diagnosed by computed tomography were embolism in 41 patients, cerebral hypoperfusion in 16 and unknown in 24. Incremental risk factors for postoperative cerebral complications were: operation early in the series advanced age at surgery, preoperative renal failure, aortic arch lesions, atherosclerotic aneurysm, aortic arch procedures and clamping of the aortic arch. CONCLUSIONS Although there was an increased incidence of advanced age and complex lesions in patients with aortic aneurysm, an improvement in surgical results has recently been achieved using advanced diagnostic and surgical techniques.

Repair for aneurysms of the entire descending thoracic aorta or thoracoabdominal aorta using a deep hypothermia

OBJECTIVE Replacement of the entire descending aorta or of the thoracoabdominal aorta still has a significant risk for postoperative paraplegia. Surgical strategies using a deep hypothermia to protect the spinal cord or viscera are discussed. METHODS From April 1994, 25 patients underwent graft replacement of the entire descending aorta (13 patients) or thoracoabdominal aorta (12 patients) using a deep hypothermia. Five patients had atherosclerotic aneurysms and 20 had aortic dissection. There were 20 males and 5 females, whose age ranged from 26 to 72 years old, 47 years old in average. Surgery consisted with proximal anastomosis using deep hypothermia (18 degrees C) with retrograde cerebral perfusion by elevating central venous pressure to 20 mmHg, reconstruction of the intercostal arteries, and distal open anastomosis, while perfusing the brain and heart. Proximal open anastomosis was used with retrograde cerebral perfusion technique in 18 patients. Averaged number of reconstructed intercostal arteries was 2.1 for each patient. RESULTS No early mortality was found and one patient died of respiratory failure 6 months after surgery. One patient had a postoperative stroke and one had a delayed onset of paraplegia 2 days after operation. The cause of paraplegia was secondary hypoxemia and hypotension due to pneumonia. CONCLUSION Utilization of the deep hypothermia in surgery for aneurysms of the entire descending aorta or of the thoracoabdominal aorta provided an adequate protection of the spinal cord as well as the abdominal viscera, eliminated clamp injury or cerebral embolization of debris or thrombi, and afforded excellent surgical exposures.

Surgical strategies in managing organ malperfusion as a complication of aortic dissection.

Between December 1978 and March 1994, 48 of 312 patients who underwent surgery for aortic dissection were diagnosed with major vascular complications. There were 18 patients with type A dissection and 30 patients with type B. In 23 patients with acute dissection, the site of vascular obstruction was the abdominal aorta in 12 patients, brachiocephalic artery in 7, iliac artery in 4, left common carotid artery in 3 and thoracic aorta in 2. In 26 patients with chronic dissection, the site of vascular obstruction was the abdominal aorta in 13 patients, brachiocephalic artery in 10, renal artery in 5, iliac artery in 4, superior mesenteric artery in 2, left common carotid artery in 2 and celiac artery in 1. Fifteen patients underwent proximal repair of the aorta during the acute stage, including the ascending aorta in 6 patients, from ascending aorta to arch in 7, arch to descending aorta in 1, thoracoabdominal aorta in 1, and entry closure in 1. In the acute stage, eight patients had palliative surgery, including aortic fenestration in four patients, axillo-femoral bypass in two, cross-over bypass to the iliac or femoral artery in one, bypass to superior mesenteric artery in one, bypass to the renal artery in one, and ileum resection in one. During the chronic phase, seven patients with type B dissection, who had malperfused unilateral renal artery, underwent proximal aortic repair.(ABSTRACT TRUNCATED AT 250 WORDS)

Utilization of Triple‐Lumen Balloon Catheter for Occlusion of the Ascending Aorta During Distal Aortic Arch Surgery with Hypothermic Retrograde Cerebral Circulation TechniqueThrough Left Thoracotomy

A technique of using a triple‐lumen balloon catheter for occlusion of the ascending aorta in patients with distal aortic arch aneurysm during open proximal anastomosis utilizing hypothermic retrograde cerebral circulation technique through left thoracotomy was described. The balloon greatly facilitated (1) occlusion of the ascending aorta without cross clamping, (2) delivery of cardioplegic solution, (3) suctioning blood pooled in the aortic arch, and (4) prevention of entrance of debris into the left ventricle or coronary arteries.

Surgery for aortic dissection with intimal tear in the transverse aortic arch.

OBJECTIVES This study reports surgical experience of 72 cases of aortic dissection with intimal tear in the transverse aortic arch. METHODS Of 325 patients with aortic dissection, 72 (22.2%) had a tear in the arch, including 27 with acute dissection and 45 with chronic dissection. Mean age at surgery was 60.8 +/- 14.1 years. The dissection was localized from the ascending aorta to the arch in 30 patients and extensive from the ascending aorta to the descending aorta in 42. Surgeries consisted of total arch replacement in 50 patients, hemiarch replacement in 20, and extra-anatomical bypass in 1. In the initial series, cardiopulmonary bypass for brain protection during arch procedures was selective cerebral perfusion (61 patients), but since July 1993 deep hypothermic circulatory arrest with retrograde cerebral perfusion was exclusively utilized (8 patients). RESULTS Hospital mortality was 9.7%, 11.1% of the patients who had acute dissection and 8.8% with chronic dissection. There has been no mortality since February 1993. The mean follow-up period was 51 +/- 37 months, and there were 3 late deaths. The 5 and 10 year survival rate was 85.3 +/- 4.8 in all patients, 84.3 +/- 8.9% with acute dissection, and 85.5 +/- 5.7% with chronic dissection. The 5 and 10 year survival was 79.8 +/- 7.1 with extensive dissection, and 93.5 +/- 6.5% with localized dissection. During follow-up, 6 patients underwent subsequent aortic surgeries. The freedom from reoperation at 5 years and at 10 years was 91.4 +/- 4.8% and 65.6 +/- 14.4%, respectively. In patients with acute dissection it was 92.3 +/- 7.4% and 61.5 +/- 25.6% at 5 years and 10 years, while with chronic dissection it was 87.0 +/- 7.0% and 44.0 +/- 17.3% at 5 years and 10 years, respectively (n.s.). The freedom from subsequent reoperation for the aorta in all patients was 91.4 +/- 4.8% at 5 years and 10 years was 65.6 +/- 14.4%. With acute dissection it was 92.3 +/- 7.4% at 5 years and 61.5 +/- 25.6% at 10 years, while that with chronic dissection it was 91.3 +/- 5.9% and 65.7 +/- 16.8% at 5 years and 10 years respectively (n.s.). The freedom from all reoperations with extensive dissection at 5 years and 10 years was 86.6% +/- 7.2% and 34.2 +/- 17.3%, respectively, moreover, the freedom from reoperations with localized dissection at 5 and at 10 years was 90.0 +/- 9.5% (n.s.). However, the freedom from subsequent aorta reoperation with extensive dissection at 5 years and 10 years was 86.6 +/- 7.2% and 56.0 +/- 16.0%, respectively, while with localized dissection it was 100% at 10 years (P < 0.01). CONCLUSION Early and late surgical result for arch dissection was satisfactory with a surgical principle of resecting the aortic segment that contains the initial intimal tear and graft replacement.

Evaluating Japanese patients with the Marfan syndrome using high-throughput microarray-based mutational analysis of fibrillin-1 gene.

Marfan syndrome (MS) is an inherited connective tissue disorder, and detailed evaluations of multiple organ systems are required for its diagnosis. Genetic testing of the disease-causing fibrillin-1 gene (FBN1) is also important in this diagnostic scheme. The aim of this study was to define the clinical characteristics of Japanese patients with MS and enable the efficient and accurate diagnosis of MS with mutational analysis using a high-throughput microarray-based resequencing system. Fifty-three Japanese probands were recruited, and their clinical characteristics were evaluated using the Ghent criteria. For mutational analysis, an oligonucleotide microarray was designed to interrogate FBN1, and the entire exon and exon-intron boundaries of FBN1 were sequenced. Clinical evaluation revealed more pulmonary phenotypes and fewer skeletal phenotypes in Japanese patients with MS compared to Caucasians. The microarray-based resequencing system detected 35 kinds of mutations, including 23 new mutations. The mutation detection rate for patients who fulfilled the Ghent criteria reached 71%. Of note, splicing mutations accounted for 19% of all mutations, which is more than previously reported. In conclusion, this comprehensive approach successfully detected clinical phenotypes of Japanese patients with MS and demonstrated the usefulness and feasibility of this microarray-based high-throughput resequencing system for mutational analysis of MS.