[Sweet's syndrome after off-pump coronary artery bypass grafting].

We report a 73-year-old man with myelodysplastic syndrome (MDS) who developed Sweet's disease after off-pump coronary artery bypass grafting (OPCAB). Coronary angiography showed severe 3 vessel disease. We conducted OPCAB on triple vessels using bilateral internal thoracic artery and saphenous vein grafts. He had a high fever and rubor around the median skin incision on 5 postoperative day. Skin biopsy demonstrated acute febrile neutrophilic dermatitis (Sweet's disease). The cutaneous lesions improved gradually by corticosteroids. A careful attention should be paid postoperatively in a patient with hematological disorders such as MDS, aplastic anemia, and malignancy.

[Aortic valve replacement through right anterolateral thoracotomy for aortic stenosis after mediastinal radiation therapy].

A 76-year-old woman had severe aortic stenosis on transthoracic echocardiography [aortic valve area (AVA): 0.7 cm2, max pressure gradient (PG): 108 mmHg]. Since she was on radiation therapy for breast cancer, we considered that median sternotomy was a risk factor for mediastinitis, and right thoracotomy was chosen for aortic valve replacement. The operation was performed through a right anterolateral thoracotomy. Cardiopulmonary bypass was established with right femoral artery cannulation, right atrial cannulation, and right superior pulmonary vein cannulation for venting. The patient's postoperative course was uneventful. This method appears to be an alternative approach for aortic valve replacement in patients that are not suitable candidates for median sternotomy.

Endovascular treatment of experimental cerebral aneurysms using thermoreversible liquid embolic agents.

SUMMARY: We have developed a new embolic agent, thermoreversible gelation polymer (TGP). This polymer is unique in that solidification occurs at body temperature. The utility of this new liquid embolic agent for the treatment of large experimental aneurysms was evaluated angiographically. TGP remains liquid at temperatures below the sol-gel transition temperature (TT) and becomes gelatinous above the TT. TGP can also be used to slowly deliver biologically active substances such as growth factors or engineered cells. In this study, TGP was mixed with radiopaque material without solvent. Bilateral common carotid arteries of swine (n=5) were used for surgical creation of lateral aneurysms, then 1 aneurysm in each animal was embolized using TGP without any protection device. The remaining untreated aneurysm in each animal was used as a control. All aneurysms were successfully embolized using TGP. No distal migration of TGP was observed when aneurysms were embolized without using protection devices. TGP can be safely used to embolize experimental aneurysms. Embolization of aneurysms with a protection device needs to be evaluated. Further modifications such as mechanical stability and use as a drug delivery system will be necessary prior to the clinical application of TGP.

[Aortic root reconstruction in elderly patients].

Operative indications for aortic root reconstruction generally include aortic root aneurysm, root destruction in acute dissection, extensive annular abscess in infective endocarditis, and small aortic annuls. In elderly patients, Bentall operation with bioprosthesis should be one of the standard operation because bioprosthesis in aortic position demonstrated excellent long-term valve durability. Freestyle aortic bioprosthesis has been increasingly implanted as a full root replacement in elderly patients with small aortic annuls and carcified aortic root. When aortic valve is nearly normal, valve-sparing aortic root replacement can be an ideal operation without need for prosthetic valve. Indication for valve-sparing operation should be considered when the patient is physically and socially active and does not carry significant comorbidity.

[Novel strategy for thoracoabdomianl aortic aneurysm repair; intraoperative selective perfusion of the Adamkiewicz artery].

We report our method for delineating the Adamkiewicz artery using multidetector row computed tomography (MDCT) with selective perfusion using a distal perfusion cannula that is clinically available for off-pump coronary artery bypass (OPCAB). The tip of a distal perfusion catheter (Medtronic Quickflow, Minneapolis) designed for OPCAB was applicable for selective perfusion of the segmental arteries. The femoro-femoral venoarterial bypass was branched off into selective perfusion of the segmental arteries, using an independent roller pump and heat exchanger. Our method of visualization of the Adamkiewicz artery was MDCT scanning with injection of contrast medium directly into the proximal descending aorta: namely, "CT during aortography". Lower descending aorta to abdominal aorta (the range involving the aneurysm) was scanned in a cephalad-to-caudal direction using a detector collimation of 4 x 1.25 mm with a table speed of 9.4 mm/sec, pitch of 6, and image thickness of 1.25 mm. All images were reviewed on a workstation to investigate the continuity between the Adamkiewicz artery and its proximal segmental artery with paging, mulitplanar reformation and curved planar reformation. Distal perfusion cannulae of 2.0 mm in diameter were inserted into the respective intercostal arteries. 4-0 polyethylene sutures were placed to tourniquet the catheters. Segmental arteries were perfused with total flow of approximately 80 ml/min at a circuit pressure of 120 mmHg. Reattachment of the ninth intercostal arteries related to the Adamkiewicz artery was carried out. A total of 6 consecutive 6 patients with thoracoabdominal aortic aneurysm (TAAA) have undergone graft replacement by the methods described, since April 2002. All patients survived surgery without any neurological complications. This method is expected to minimize the ischemic time of the spinal cord and attenuate the reperfusion injury.

Angiogenesis after sintered bone implantation in rat parietal bone.

We studied the effect of bone substitutes on revascularization and the restart of blood supply after sintered bone implantation in comparison with synthetic hydroxyapatite implantation and fresh autogenous bone transplantation (control) in rat parietal bones. Methods for the study included the microvascular corrosion cast method and immunohistochemical techniques were also used. The revascularization of the control group was the same as that for usual wound healing in the observations of the microvascular corrosion casts. The sintered bone implantation group was quite similar to that of the control group. In the synthetic hydroxyapatite group, immature newly-formed blood vessels existed even on the 21st day after implantation and the physiological process of angiogenesis was interrupted. Immunohistochemically, vascular endothelial growth factor (VEGF), which activates angiogenesis, appeared at the early stages of both the control group and the sintered bone implantation group. VEGF reduced parallel with the appearance of the transforming growth factor factor-beta-1 (TGF-beta-1), which obstructs angiogenesis, and the angiogenesis passed gradually into the mature stage. In the hydroxyapatite implantation group, TGF-beta-1 appeared at the early stage of the implants. The appearance of VEGF lagged and it existed around the pores of hydroxyapatite even on the 21st day of the implantation. Proliferation and wandering of endothelial cells continued without any maturing of the vessels. These findings suggest that the structure and the components of the implant material affect angiogenesis after implantation as well as new bone formation.

[Combined carotid endarterectomy and off-pump coronary artery bypass grafting].

Patients with angina undergoing carotid endarterectomy have a high mortality. A 74-yaer-old man who has severe carotid stenosis was performed combined carotid endarterectomy and off-pump coronary artery bypass grafting successfully. At first, carotid endarterectomy was performed with Jamieson's specially designed dissector, which allow simultaneous dissection and removal blood from the surgical field. Secondly, then off-pump CABG was performed. Skeletonized internal mammary artery was harvested with ultrasound dissector. The advantage of that the dissected artery is not only long and greater blood flow, but also less damage to sternal blood flow which prevent infection and complications. Then internal mammary artery was anastomosed to left anterior discending artery with Octopus II stabilizer. After the operation, he recovered uneventfully without neurological complication. Combined single staged carotid endarterectomy and off-pump CABG appears to be a safe method.

Leukocyte-depleted reperfusion after long cardioplegic arrest attenuates ischemia-reperfusion injury of the coronary endothelium and myocardium in rabbit hearts.

OBJECTIVE: Cardiopulmonary bypass activates leukocytes, which should injure the coronary endothelium and myocardium during reperfusion especially after long cardioplegic arrest with long cardiopulmonary bypass time. The present study was designed to determine the protective efficacy of leukocyte-depleted reperfusion in blood-perfused parabiotic isolated rabbit hearts as a surgically relevant model with long cardioplegic arrest. METHODS: Each isolated rabbit heart, with a latex balloon inserted in the left ventricle, was parabiotically blood-perfused using a modified Langendorff column. The left ventricular developed pressure (DP), rate of pressure development (dP/dT), and coronary flow with a left ventricular end-diastolic pressure of 10 mmHg were measured before ischemia and after 15, 30, 45, and 60 min reperfusion after 4 h cardioplegic arrest kept at 20 degrees C (control, n=10). Leukocyte-depleted reperfusion was done in the test group (n=10). The endothelium of the coronary artery was observed by scanning electron microscopy (SEM) with percent injured area of endothelial cells measured to evaluate the extent of endothelial ischemia-reperfusion injury. RESULTS: The control hearts showed 53.3, 54.3, 48.4, and 39.0% recovery of DP compared to the pre-ischemia baseline data at 15, 30, 45, and 60 min after reperfusion began respectively. Leukocyte-depleted reperfusion enhanced the recovery of DP at 45 min (81.3%, P=0.0021) and 60 min (85.8%, P=0.0005) after reperfusion compared with that in the control group. The control hearts revealed 58.8%, 59.8%, 52.6%, and 43.4% recovery of dP/dT compared to the pre-ischemia baseline data at 15, 30, 45, and 60 min after reperfusion began, respectively. Leukocyte-depleted reperfusion also enhanced the recovery of dP/dT at 45 min (93.2%, P=0.0071) and 60 min (98.8%, P=0.0011) after reperfusion compared with that in the control group. There was also improvement of the recovery of coronary flow by leukocyte-depleted reperfusion (97.2%) compared with that in the control group (58.3%) after 60 min reperfusion (P=0.0121). Scanning electron microscopy showed that 69. 7% of coronary endothelial cells were morphologically injured in the control group. In contrast, leukocyte-depleted reperfusion prevented the extent of coronary endothelial damage with less injured area (0. 5%, P=0.0002). CONCLUSIONS: Leukocyte-depleted reperfusion improved functional recovery with reduced coronary endothelial injury after long cardioplegic arrest.

Successful valve-sparing in aortic root reconstruction under endoscopic guidance.

OBJECTIVE: Aortic insufficiency (AI) associated with ascending aneurysm can be corrected by valve-sparing aortic root reconstruction ('David' reimplantation, 'Yacoub' remodeling). Intraoperative endoscopic evaluation in the aortic root may help to clarify the procedure and to access competence of the preserved valve. METHODS: Following cross-clamping of the ascending aorta, an endoscopy was inserted into the proximal aortic root. Perfusion of crystalloid cardioplegia enabled the visualization of the pressure-loaded valve in the closed position. Conventional macroscopic evaluation would have overlooked valve prolapse because of a release from perfusion pressure. Valve coaptation was imaged directly before and after the valve-sparing procedure. A total of 17 patients underwent aortic root reconstruction under endoscopic guidance. Indications of the valve-sparing were determined with endoscopic findings. The degree of AI before and after the surgery was evaluated by aortography and scored (0, none; 1 trivial; 2, mild; 3, moderate; 4, severe). RESULTS: Remodeling was employed to eight patients and reimplantation to four. The other five patients were replaced with prosthetic valved-conduit. There was no early and late mortality. Before and after the valve-sparing surgery, grades of AI were significantly reduced. Three patients who underwent reimplantation procedure required late valve replacement for late progression of AI, however, none of the patients with remodeling required reoperation. CONCLUSION: Introduction of an endoscopy successfully reduced postoperative AI and clarified indications and limitations of valve-sparing aortic root operations.

[Influence of acute aortic dissection on long-term results of aortic root reconstruction in patients with Marfan's syndrome].

Objective of this study is to evaluate influence of acute aortic dissection on long-term results of aortic root reconstruction in patients with Marfan's syndrome. 19 patients who underwent consecutive aortic root reconstruction between 1985 May to 1998 February were retrospectively reviewed. Patients who associated acute aortic dissection at the time of operation (group D, n = 7) were compared long-term results with those who did not (group non-D, n = 12). Mean follow-up period was 5.1 +/- 3.2 years and longest follow-up term was 12.5 years. In each group early postoperative death was found in one patient. In-hospital mortality in each group were respectively; 14.2% and 8.3%. Late deaths were found in four patients who all belonged to group D, respectively caused by; rupture of thoracoabdominal aneurysm, DIC after subsequent thoracoabdominal surgery, sepsis due to prosthetic valve endocarditis, and sudden death. Actuarial overall survival rate including operative death in D and non-D group were respectively; 0.0 +/- 0% at 6.6 years and 91.1 +/- 8.0% at 12 years. Overall cumulative survival rate was 56.6 +/- 14.0%. Freedom from cardiovascular events, in D and non-D group were respectively; 0.0 +/- 0% at 6.6 years and 60.0 +/- 25.3%, and freedom free form dilatation of residual aorta were respectively; 0.0 +/- 0% at 6.6 years and 100.0 +/- 0% at 12 years. Freedom from subsequent cardiovascular surgery in group D, group non-D and over-all patients were respectively; 0.0 +/- 0% at 6.6 years, 60.0 +/- 25.3% at 12 years and 42.6 +/- 20.2%. In this study, acute aortic dissection in Marfan's syndrome significantly increased late cardiovascular events including dilatation of residual aorta, subsequent aortic surgery and late mortality. On the other hand, excellent long-term results after aortic root reconstruction were found in non-dissection Marfan's syndrome. Considering high incidence of late dilatation of residual aorta, simultaneous total arch replacement with aortic root reconstruction is recommended in acute dissecting Marfan's syndrome. Whereas, preventive simultaneous arch replacement is not required in non-dissecting Marfan's syndrome because of less postoperative vascular events.

[A case of fulminant myocarditis treated by ABIOMED BVS 5000 biventricular support].

Reported is a case of acute fulminant myocarditis with profound circulatory compromise. The patient was supported with biventricular assist devices (BVS 5000 ; ABIOMED Inc., Danvers, Mass.). The patient had remarkable recovery of ventricular function, which allowed for the removal of the device after 269 hours of support and the recovery to the normal quality of life. This case shows the success of mechanical support to treat potentially fatal disease process.

[Reoperation after aortic valve replacement and root reconstruction].

Between 1984 and 1997, 127 patients in our institution underwent single aortic valve replacement (AVR) with the St. Jude Medical valve (group S) and 11 patients with a porcine pericardial valve (group T). In the same period, 45 patients underwent aortic root reconstruction, among which 39 patients underwent the Bentall procedure using Carrel patch coronary reanastomosis (group B). The other 6 patients were treated with valve-sparing aortic root reconstruction (group V), among which the reimplantation method was used in 4 patients and the remodeling method in 2. The mean and total follow-up periods of the AVR and aortic root reconstruction groups were 6.9 +/- 1.9 year/735 patient-years and 4.9 +/- 3.9/years/196 patient-years respectively. The actuarial overall survival rates in group S and T at 10 years were; 73.8 +/- 7.0% and 85.7 +/- 13.0%, respectively The probabilities of freedom from reoperation at 12 years in group S and T were 97.7 +/- 2.3% and 62.5 +/- 21.3%, respectively. Only one patient in group S required reoperation because of valve thrombosis, while 2 patients in group T underwent reoperation for prosthetic valve endocarditis. The actuarial overall survival rate after aortic root reconstruction at 10 years was 62.6 +/- 9.6%, while that of patients with acute aortic dissection and those who did not were 44.4 +/- 15.7% and 71.7 +/- 11.5%, respectively. The event-free rate at 12 years after aortic root reconstruction (group V+B) was 79.1% +/- 20/9%. The reason for reoperation in the 2 patients who underwent the Bentall procedure were prosthetic valve endocarditis in one and psuedoaneurysm at the right coronary anastomosis in the other. The reason for reoperation in one patient who formed a pseudoaneurysm was likely due to an oversized conduit hole for the Carrel patch coronary anastomosis. One patient in whom the native valve was preserved using the David reimplantation procedure required reoperation because of valve degeneration 17 months after the initial surgery, possibly due to valve rubbing on the vascular conduit because of a modified geometry of the Valsalva sinuses. In conclusion, because of the low rate of long-term mortality and reoperation, the St. Jude Medical valve is an excellent prosthesis for AVR. AVR with a porcine pericardial valve yields favorable results in terms of the low long-term mortality although the incidence of reoperation remains high. Aortic root reconstruction with the Bentall procedure using the Carrel patch method yields acceptable results in terms of long-term mortality and low rate of reoperation, although acute aortic dissection is an incremental preoperative risk factor. The early results of aortic valve-sparing root reconstructive surgery are encouraging, with excellent clinical outcomes and patient quality of life. Nevertheless, the indications for the procedure must be carefully considered.

[Initial clinical experiences of the ABIOMED BVS SYSTEM 5000 in Japan].

The initial clinical experience of the ABIOMED BVS SYSTEM 5000 in Japan is reported. The system is a paracorporeal pulsatile assist device intended for temporary ventricular support. It consists of a pneumatic drive console, a blood pump, and the atrial and arterial cannulas. The pump is of a dual chamber design, with the upper chamber as a passive, gravity filled resevoir and the lower chamber as a pumping chamber. Since the system is designed to be simple, safe and automatically controlled, no additional personnel is required to control perfusion. This report describes our initial clinical experiences with the ABIOMED BVS SYSTEM 5000 in Japan. This device was used in three patients with post cardiotomy cardiogenic shock and fulminant myocarditis. The first patient developed acute occlusion of left main coronary artery who required emergent surgical revascularization following PTCA and stent implantation. He couldn't wean from CPB and required the insertion of an LVAD. The second case suffered from a cardiac arrest after CABG and could not be resuscitated. The ABIOMED BVS 5000 was inserted and the patient successfully weaned from support. The third patient developed fulminant myocarditis and was supported with the system for 269 hours and was successfully weaned after near complete myocardial recovery. Our initial experience with the ABIOMED BVS SYSTEM 5000 indicates that the system can provide complete cardiac support allowing full recovery from a cardiac variety of causes of dysfunction. The device has the potential to improve the survival rate of patients with severe acute recoverable myocardial damage. It is expected that this device can be a viable tool for treatment of intractable heart diseases.

Initial experience with the Nikkiso centrifugal pump during thoracoabdominal aortic aneurysm repair.

PURPOSE: Several centers use atriodistal bypass (ADB) as a protective adjunct against distal ischemia during extensive thoracoabdominal aortic aneurysm (TAAA) repair. Most current ADB circuits use indirect-drive centrifugal pumps. The purpose of this report is to describe our initial clinical experience with the Nikkiso pump, a more compact direct-drive centrifugal pump recently developed at Baylor, for ADB during TAAA repair. METHODS: The Nikkiso pump was used for ADB perfusion in 10 consecutive patients during graft repair of TAAAs (six Crawford extent I and four extent II). Two patients had aortic dissection. In the four patients who had extent II repairs, selective renal and visceral perfusion was also performed with the Nikkiso pump. RESULTS: No mechanical pump malfunctions or adverse events related to the device occurred. All 10 patients survived and were discharged from the hospital. No patient had paraplegia after surgery. Two patients had delayed lower extremity weakness after undergoing extent I repairs; both recovered and were ambulating at the time of discharge. No complications were associated with bleeding or cerebral, respiratory, renal, or hepatic function. CONCLUSIONS: Our initial experience with the Nikkiso centrifugal pump during TAAA repair demonstrated excellent pump function that provided sufficient flow for both distal aortic and selective organ perfusion. The prevention of permanent spinal cord injury and distal organ failure was successful in this group.

Recent advances in the gyro centrifugal ventricular assist device.

The gyro pump was developed as an intermediate-term assist pump (C1E3) as well as a long-term centrifugal ventricular assist device (VAD). The antithrombogenic design concept of this pump was confirmed throughout three 1 month ex vivo studies. The normalized index of hemolysis (NIH) of this gyro C1E3 model was lower than that of the BP-80. In the next step, a miniaturized centrifugal blood pump (The Gyro permanently implantable model PI-601) has been developed for use as a permanently implantable device after design optimization. A special motor design of the magnet circuit was utilized in this system in collaboration with the University of Vienna. The priming volume of this pump is 20 ml. The overall size of the pump actuator package is 53 mm in height, 65 mm in diameter, 145 ml of displacement volume, and 305 g in weight. This pump can provide 5 L/min against 120 mm Hg total pressure head at 2,000 rpm. The NIH value of this pump was comparable to that of the BP-80. The gyro PI-601 model is suitable for a VAD. The expected life from the endurance study is approximately 8 years. The evolution from C1E3 to the PI-601 converts this pump to a totally implantable centrifugal pump. Recent technologic advances in continuous flow devices are likely to realize a miniaturized and economical totally implantable VAD.

Therapeutic and physiological artificial heart: future prospects.

Current left ventricular assist devices (LVADs) have demonstrated admirable results. However, approximately one-fourth of the patients who require LVADs suffer from right heart failure and require additional right ventricular (RV) assist devices (RVADs). The RV failure impairs the splanchnic circulation, subsequently developing into multiorgan failure (MOF). An aggressive application of a biventricular assist device (BVAD) is the best way to avoid and treat MOF because the BVAD reduces splanchnic congestion. Also, because the BVAD allows retention of the natural heart, recovery of the heart function can be expected after long-term assist. This benefit cannot be expected from conventional total artificial hearts. Although there are no implantable clinical BVAD systems in existence today, present advanced technologies in rotary blood pumps can enable these systems to be totally implantable. So, we should focus on developing a totally implantable BVAD system. The implantable BVAD will be a therapeutic and physiological total artificial heart, and it will be a common home health care device in the near future.