Masanori Ogiwara

Successful bridge to resynchronization therapy with a left ventricular assist system in a patient with idiopathic dilated cardiomyopathy

Implantation of a left ventricular assist system (LVAS) in patients with idiopathic dilated cardiomyopathy (DCM) may improve cardiac function and allow explantation of the device. Generally, an ejection fraction of more than 40% is considered necessary for successful weaning from an LVAS, but less than 10% of DCM patients with an LVAS can achieve such a significant recovery of cardiac function. Cardiac resynchronization therapy, or atrial-synchronized biventricular pacing, has been found to treat congestive heart failure and ventricular dyssynchrony effectively. Here we report on a patient with an LVAS, in whom enough functional recovery could be obtained with resynchronization therapy for the device to be explanted successfully. A 32-year-old man was implanted with a Toyobo-NCVC paracorporeal LVAS to treat his intractable heart failure caused by idiopathic dilated cardiomyopathy. While on the LVAS for 8 months, his cardiac function recovered to some extent. The ejection fraction of his left ventricle (LVEF) improved from 9% to 41%. He chose explantation of the device rather than heart transplantation. Because he occasionally showed a wide QRS pattern on his ECG, epicardial biventricular pacing leads as well as a biventricular pacemaker were implanted on LVAS explantation surgery. An echocardiogram 2 weeks after explantation showed a marked difference in his LVEF by switching his biventricular pacing on and off (40% with biventricular pacing on and 29% with it off). Biventricular pacing may help recovery of cardiac function in selected LVAS patients and contribute to the increase in bridge to recovery cases.

Fifteen-month circulatory support for sustained ventricular fibrillation by left ventricular assist device

1. Pennington DG, McBride LR, Peigh PS, Miller LW, Swartz MT. Eight years’ experience with bridging to cardiac transplantation. J Thorac Cardiovasc Surg. 1994;107:472-81. 2. Peterze B, Lonn U, Jansson K, Rutberg H, Casimir-Ahn H, Nylander E. Long-term follow-up of patients treated with an implantable left ventricular assist device as an extended bridge to heart transplantation. J Heart Lung Transplant. 2002;21:604-7. 3. Bank AJ, Mir SH, Nguyen DQ, Bolman RM 3rd, Shumway SJ, Miller LW, et al. Effects of left ventricular assist devices on outcomes in patients undergoing heart transplantation. Ann Thorac Surg. 2000;69: 1369-75. 4. Sun BC, Catanese KA, Spanier TB, Flannery MR, Gardocki MT, Marcus LS, et al. 100 long-term implantable left ventricular assist devices: the Columbia Presbyterian interim experience. Ann Thorac Surg. 1999;68:688-94. 5. Massad MG, McCarthy PM, Smedira NG, Cook DJ, Ratliff NB, Goormastic M, et al. Does successful bridging with the implantable left ventricular assist device affect cardiac transplantation outcome? J Thorac Cardiovasc Surg. 1996;112:1275-83.

Severe pulmonary stenosis and aortopulmonary fistula caused by a dissecting aneurysm in the ascending aorta

Discussion Surgical repair of aortic coarctation has expanded to include resection with end-to-end anastomosis, prosthetic patch aortoplasty, subclavian flap aortoplasty, and aortic resection with graft replacement. Because further aortic growth is not a problem in adult patients, graft replacement or bypass is often used and produces the best results. As the aortic wall in the portion of coarctation was thought to be fragile in our case because of the median necrosis, we used an open proxymal anastomosis technique to avoid possible aortic injury caused by crossclamping. The central cannulation technique is preferred for correction of postductal coarctation of the aorta to secure sufficient cerebral perfusion. In our case, this technique also had the advantage of preventing scattering of debris by the blood jet in an aortic aneurysm to cerebral blood flow. We prefer insertion of a venous cannula into the right atrium through the right femoral vein rather than insertion into the main pulmonary artery, as originally reported by Westaby and colleagues, because we have sometimes found that the wall of the main pulmonary artery is very fragile and thus susceptible to injury. We routinely insert a double-staged venous cannula through the right femoral vein in operations for descending aortic aneurysms and have experienced no technical problems. In conclusion, our “modified” central cannulation technique and open proxymal anastomosis technique seem to be safe. This is an appropriate approach for surgical correction, and we recommend it as the standard approach for the coarctation of the aorta in adults.

Lethal thrombus in the carotid artery during operation for acute aortic dissection with cerebral malperfusion.

A drowsy patient with acute type A aortic dissection and cerebral malperfusion required emergency operation. Because the right carotid artery was totally obstructed, cerebral perfusion was first restored by cannulating it and the left femoral artery before midline sternotomy. However, a long fresh thrombus was found flowing backward from the obstructed carotid artery. This thrombus was removed, and both arteries were connected through a Y-shaped extracorporeal circulation circuit to reperfuse the brain. During the subsequent aortic procedure, both arteries were used for arterial inflow. Such thrombi can cause grave postoperative neurologic dysfunction. Carotid artery cannulation is mandatory in such cases.

Combined coronary artery bypass grafting and abdominal aortic aneurysm repair.

The purpose of this paper was to assess the results and feasibility of simultaneous coronary artery bypass grafting and abdominal aortic aneurysm repair. Twenty nine patients with a mean age of 65 years underwent simultaneous coronary artery bypass grafting and abdominal aortic aneurysm repair between June 1990 and March 2002. All patients had significant coronary artery disease and were considered as indicated for coronary artery bypass grafting. This was performed first in 28 patients and simultaneously with abdominal aortic aneurysm repair in one, with a mean number of grafts of 2.5, a mean aortic cross-clamp time of 40 minutes, and a mean bypass time of 115 minutes. Eight straight and 21 bifurcated grafts were employed. The total operating time averaged 400 minutes. The median postoperative hospital stay was 18 days. One patient died of stroke and mediastinitis, for a mortality rate of 3.5%. This experience suggests that combined coronary artery bypass grafting and abdominal aortic aneurysm repair is both safe and effective.

Human serum induces apoptosis of xenogeneic cardiomyocytes in vivo and in vitro

Abstract: Discordant xenotransplantation is complicated by delayed xenograft rejection (DXR). Previous studies have demonstrated that anti‐apoptotic genes are protective against DXR. This study examines the hypothesis that apoptosis plays a role in human anti‐xenograft responses. C57BL/6 mice and NOD SCID mice were given a single intravenous injection of either a lethal dose (LD, survival < 30 min) or a sublethal dose (SLD) of human serum, and isolated pig and mouse rod‐shaped cardiomyocytes were exposed to human serum in vitro. In situ detection of apoptotic cells in mouse hearts was assessed using a terminal deoxynucleotidyl transferase‐mediated dUTP nicked‐end labeling assay. Mice transfused with human serum had approximately a 10‐fold increased percentage of apoptotic cells after SLD 18 h post‐injection compared with animals given saline, and a fourfold increase over LD. Administration of cobra venom factor (CVF) decomplemented SLD 18 h did not significantly (P > 0.05) alter the percentage apoptosis. The addition of 20 mM Gal‐α‐1,3‐Gal to SLD 18 h significantly (P < 0.05) reduced percentage apoptosis to levels comparable to saline treated control animals. In vitro using mouse and pig cardiomyocytes demonstrated parallel results as in vivo experiments.

Allograft pulmonary artery root replacement for refractory isolated pulmonic valve endocarditis.

Abstract A 45-year-old diabetic woman was subjected to percutaneous cardiopulmonary support for a life-threatening pulmonary embolism. One month later, she developed isolated pulmonic valve endocarditis. The causative organism was methicillin-resistant Staphylococcus aureus. Because of the uncontrollable infection and residual pulmonary hypertension, she underwent pulmonary artery root replacement with a cryopreserved pulmonary allograft. The postoperative course was very good. In this case, allograft implantation with a full root played a very important role because this method permitted thorough resection of the infected tissues and reconstruction which is highly resistant to infection.

Active Cerebral Perfusion during Carotid Endarterectomy

A patient with critical stenoses in the bilateral internal carotid arteries (ICA) required multivessel coronary revascularization. The diameter of the left ICA was far greater than the right, which strongly suggested that the cerebral circulation was highly dependent on the left. During left ICA endarterectomy, active cerebral perfusion of 300 mL·min−1 at 23°C using an extracorporeal circulation was employed through the ICA under repair. Subsequently, coronary bypass was performed on-pump with the heart beating. The postoperative course was very good.

Efficacy of Preoperative Antibiotic Therapy for the Treatment of Vascular Graft Infection

Objective: We aimed to assess the efficacy of preoperative antibiotic therapy for the treatment of prosthetic graft infection. Materials and Methods: We retrospectively analyzed the treatment strategies used for managing patients with prosthetic vascular graft infections between 2000 and 2016. The patients were divided into two groups: early antibiotic (EA) group, those who were administered with antibiotics ≥2 weeks preoperatively and late antibiotic (LA) group, those who were administered with antibiotics <2 weeks preoperatively. We evaluated the outcomes including surgical procedures, length of hospital stay, and surgical revision. Results: All the surgical procedures performed in the EA group were elective surgeries. Three of the 11 surgeries performed in the LA group were emergency surgeries (P=0.16). No significant differences were observed in the operative procedure (P=0.64), operation time (P=0.37), and blood loss (P=0.63) of the two groups. Although the length of postoperative hospital stay did not significantly differ (P=0.61), the total length of hospital stay was longer in the EA group (P=0.02). Surgical revisions were performed for five patients in the LA group and for none in the EA group (P=0.04). Conclusion: Preoperative antibiotic therapy provided excellent outcomes in terms of avoiding surgical revisions in the treatment of vascular graft infection.

Idiopathic radial artery true aneurysm

A 67-year-old woman presented with an 8-mm-diameter pulsatile mass in her right forearm. The mass had been present for a year and has increased in size. She had a negative relevant medical history and no history of trauma, intervention, or venipuncture on the right arm. She did not complain of pain, numbness, or functional deficit of the arm or hand. Computed tomography angiography revealed a saccular aneurysm in the middle portion of the right radial artery (RA), and the aneurysm was filled with thrombus (A/Cover). Computed tomography angiography demonstrated no aneurysmal change in the aorta and the iliac or visceral arteries. A surgical repair was indicated for the aneurysm because the patient recently noted an increase in the size. We made a longitudinal skin incision above the aneurysm. The aneurysm was markedly eccentric in shape; however, the arterial wall structure in the opposite wall of the aneurysm seemed normal (B). After dissection, a 15-mm segment of the RA with the saccular aneurysm was resected. The RA was simply reconstructed by end-to-end anastomosis. The distal perfusion of the anastomosis was satisfactory; there was a palpable radial pulse distal to the reconstruction, and the artery had forward flow. She was discharged 3 days after surgery. Pathologic examination revealed the three-layer structure of the saccular aneurysmal wall, indicating a true aneurysm (C). Ultrasound examination 4 months after surgery confirmed forward flow in the RA. The patient’s consent to publish the case report was obtained.