Successful Reversal of Delayed Postoperative Paraplegia Complicating Emergency Total Arch Replacement for Type A Dissection / 日本心臓血管外科学会雑誌

We report a rare case of paraplegia after emergency total arch replacement for type A acute aortic dissection. A 52-year-old man was referred to our hospital for acute aortic dissection. Contrast-enhanced computed tomography showed a type A aortic dissection extending from the aortic root into the right iliac arteries. The true lumen of the descending and abdominal aorta was collapsed and blood flow to the right lower limb had decreased. Large entry and re-entry tears were revealed in the ascending and distal arch aorta, respectively. His preoperative consciousness was clear, hemodynamics were stable, and there was no evidence of paraplegia or paraparesis. Extracorporeal circulation was established by femoral artery and right atrium cannulation. Total arch replacement was performed under moderate hypothermic circulatory arrest (lowest bladder temperature : 21.9°C). The postoperative course was uneventful and he was extubated 6 h postoperatively. Postoperative hemodynamic parameters were stable, the mean blood pressure was maintained at around 70 mmHg, and limb movements were confirmed at that time. Although there was no abnormality of lower limb movement until the following morning, paraplegia occurred about 17 h after surgery. While maintaining a mean blood pressure of over 90 mmHg, urgent cerebrospinal drainage was immediately performed and combined with steroid treatment and a continuous infusion of naloxone. The neurological defect was resolved immediately after cerebrospinal drainage, and neurological function steadily improved through rehabilitation. He was discharged 20 days after surgery with no neurological defects. Late paraplegia after total replacement for type A acute aortic dissection is a rare complication. From our experience, it is suggested that early diagnosis and treatment are important for improving paraplegia.

Aortic Valve Repair for Infective Endocarditis of an Aortic Valve / 日本心臓血管外科学会雑誌

Infective endocarditis of the aortic valve tends to cause structural damage such as aortic root abscess, and aortic valve replacement is the standard treatment. However, there have been several reports on aortic valve repair for the treatment of infective endocarditis, and it has subsequently emerged as a feasible alternative to aortic valve replacement in selected patients. We report a case of aortic valve repair for infective endocarditis of the aortic valve caused by α-hemolytic Streptococcus. A 50-year-old man was admitted to our hospital with a two-month history of fever of unidentified origin. Transthoracic echocardiography revealed infective endocarditis of the aortic valve. Transesophageal echocardiography confirmed vegetation in the right coronary and non-coronary cusps, and mild aortic regurgitation. Although infection was controlled by approximately one month of antibiotic treatment, there was markedly more severe aortic regurgitation compared to the previous examination. These findings were confirmed on transesophageal echocardiography, and residual vegetation on the right coronary cusp as well as a perforation in the non-coronary cusp were confirmed. Intraoperative findings revealed a perforation in the non-coronary cusp and dehiscence, with vegetation on the right coronary cusp. The vegetation was carefully removed, the non-coronary cusp perforation was repaired with a pericardium patch, and the defect on the right coronary cusp was directly sutured with 6-0 polypropylene. Intraoperative transesophageal echocardiography revealed trivial aortic regurgitation. The postoperative course was uneventful and the patient was discharged 7 days after surgery without any complications. Antibiotics were prescribed for 3 months, and transthoracic echocardiography was performed 5 days, 1 month, and 3 months after surgery. No evidence of recurrence of aortic regurgitation or infection of the aortic valve was observed.

Beating Heart Mitral Valve Replacement via Right Thoracotomy for Ischemic Mitral Valve Regurgitation after Coronary Artery Bypass Surgery / 日本心臓血管外科学会雑誌

Reoperative valve surgery is known to be more complex and associated with increased morbidity and mortality, especially for patients with patent coronary artery bypass grafts. A 69-year old man with a history of coronary artery bypass grafting was referred to our hospital with breathing difficulties and a heart murmur. Bypass grafts were all patent, but due to severe ischemic mitral valve regurgitation, we performed beating heart mitral valve replacement via right thoracotomy. The procedure was performed with video assistance, and both the anterior and the posterior chordae tendineae were preserved. The postoperative course was uneventful. He was discharged 7 days after surgery without any complications. This technique is a safe and feasible option for a mitral valve reoperation that avoids graft injuries, minimizes the risks of bleeding, and shortens the operative time.

A Case of Mitral Valve Revision Surgery Necessitated by Systolic Anterior Motion of the Mitral Valve after Initial Repair / 日本心臓血管外科学会雑誌

<p>Systolic anterior motion (SAM) is a common complication of mitral valve repair surgery and occasionally requires further treatment. A 56-year-old woman with severe mitral regurgitation accompanied by posterior leaflet prolapse underwent mitral valve plasty including hour-glass-shaped resection, chordal replacement, and interrupted commissural band annuloplasty. The mitral valve was exposed via a right-sided left atriotomy. We found a large thick P2-3 scallop (27 mm in height) with ruptured and elongated chordae. After repair, transesophageal echocardiography (TEE) revealed SAM of the anterior mitral leaflet and severe mitral regurgitation upon weaning from the cardiopulmonary bypass. Although catecholamine was discontinued and volume loading applied, the SAM did not improve. We decided to revise the mitral plasty. Therefore, although the height of the P3 scallop after resection remained 17 mm, neochordae were placed once more on the basal side of the posterior leaflet, and the leaflet was shortened by placing a continuous suture near the annulus. This reduced the height of the posterior leaflet and moved the co-aptation line posteriorly. After this repair, TEE showed that the SAM had disappeared. Thus, repositioning the neochordae and shortening the posterior leaflet by applying a continuous suture effectively and rapidly eliminated the problem.</p>

Unilateral Selective Cerebral Perfusion during Aortic Valve Replacement in Patients with a Compromised Aorta / 日本心臓血管外科学会雑誌

<b>Background</b> : Aortic valve stenosis may be complicated by atherosclerotic lesions in the ascending aorta, which may cause cerebral infarction due to intraoperative dispersion of atheromas. We describe herein a safe aortic cross-clamping technique after removal of the sclerotic lesion in the ascending aorta during short-term unilateral selective cerebral perfusion and mild hypothermic circulatory arrest. <b>Methods</b> : From January 2006 to March 2014, a total of 144 patients underwent aortic valve replacement (AVR) for treatment of aortic valve stenosis. Patients who required ascending aorta replacement surgery, had infective endocarditis, or required emergency surgery were excluded. Five patients underwent AVR using unilateral selective cerebral perfusion and mild hypothermic circulatory arrest due to the presence of atherosclerotic plaques or severe calcification of the ascending aorta (Compromised Aorta group), and 139 patients underwent AVR using ascending aortic perfusion and clamping (Control group). Cardiopulmonary bypass using the right axillary and femoral arteries was started and cooled to a pharyngeal temperature of 34°C in the Compromised Aorta group. During hypothermic circulatory arrest, the brachiocephalic artery was clamped and unilateral selective cerebral perfusion was administered from the right axillary artery. The perfusion volume was adjusted to 500 to 800 ml while using the cerebral oxygen saturation monitor. After transection of the ascending aorta, the atheroma and suture line calcification were removed. A suitable site for cross-clamping was identified under direct vision, and the aorta was carefully cross-clamped. <b>Results</b> : The patients in the Compromised Aorta group required a mean circulatory arrest period of 3.8 min (range, 3.0-5.5 min). The mean minimum value of the left-side cerebral oxygen saturation was 52.0% (range, 45-58%). No patients in the Compromised Aorta group died or developed cerebral complications (95% confidence interval (CI) 0.000-0.522). Complications in the Control group included in-hospital mortality (3/140, 2.2% ; 95%CI : 0.003-0.046 ; <i>p</i>=0.899), stroke (2/139, 1.4% ; <i>p</i>=0.932), transient neurologic deficits (4/139, 2.9% ; <i>p</i>=0.867), and total cerebral complications (6/139, 4.3% ; 95%CI : 0.009-0.077 ; <i>p</i>=0.806). Additionally, there were no significant differences between the Compromised Aorta and Control groups in the operative time (345.8±71.8 vs. 333.6±85.4 min, respectively ; <i>p</i>=0.754), cardiopulmonary bypass time (196.4±63.6 vs. 199.2±50.0 min, respectively ; <i>p</i>=0.902), and aortic cross-clamp time (132.0±44.1 vs. 124.8±36.3 min, respectively ; <i>p</i>=0.666). <b>Conclusion</b> : Short-term unilateral selective cerebral perfusion and mild hypothermic circulatory arrest is a safe strategy in patients undergoing AVR with a severely atherosclerotic aorta. The outcomes of this strategy were equivalent to those in the Control group, which had fewer atherosclerotic lesions in the ascending aorta.