Masataka Yamazaki

Use of Hemoglobin Vesicles During Cardiopulmonary Bypass Priming Prevents Neurocognitive Decline in Rats

Background— Homologous blood use is considered to be the gold standard for cardiopulmonary bypass (CPB) priming in infants despite exposure of the patient to potential cellular and humoral antigens. However, the use of hemoglobin vesicles (HbVs), artificial oxygen carriers that encapsulate a concentrated hemoglobin solution within phospholipid bilayer membranes, for CPB priming may prevent neurocognitive decline in infants. The goal of this study was to determine whether HbV use offsets hemodilution caused by patient/priming volume-mismatched CPB and thereby prevents the development of postoperative neurocognitive deficits. Methods and Results— CPB was established in 28 male Sprague-Dawley rats (age, 14 to 16 weeks; weight, 450 grams) after cannulation of the tail artery and right atrium. The animals were randomly assigned to 1 of 3 groups: sham surgery (n=9), HbV (−) prime (n=10), or HbV (+) prime (n=9). CPB was conducted for 90 minutes at 200 mL/kg per minute. The hematocrit during CPB was 10.0±1.2% in the HbV (+) prime group and 9.9±1.3% in the HbV (−) prime group (P=not significant). Learning and memory function were evaluated using 2 different maze tests (Maze-1 and Maze-2, in which the arrival times to the target were measured on the first, third, fifth, and seventh postoperative days). Learning and memory function were significantly better in the HbV (+) prime group than in the HbV (−) prime group (Maze-1, P=0.012; Maze-2, P=0.042); there was no difference between the HbV (+) prime and the sham surgery group. Conclusions— The use of HbV for CPB priming may serve as a substitute for homologous blood to prevent the unacceptable hemodilution and contribute to maintenance of intact neurocognitive function.

Intraoperative Endoscopic Resection of Left Ventricular Tumors

Two cases involving patients who underwent a successful endoscopic resection of a left ventricular tumor are presented herein. One was an 82-year-old woman with a left ventricular papillary fibroelastoma, who underwent previous coronary artery bypass grafting. In an attempt to make the procedure less invasive, we used an endoscope. With a full sternotomy, cardiopulmonary bypass, and cardioplegic protection, the endoscope was inserted into the left ventricular cavity through the mitral valve. The other patient was a 63-year-old man with left ventricular papillary fibroelastoma, in whom we performed an endoscopic transaortic resection. The endoscope provided an excellent view, and the tumors were easily extracted in both cases without any complications.

Extensive total arch replacement via clamshell incision in a patient with aortic arch aneurysm and Stanford type B aortic dissection

The utility of the clamshell approach, namely, a bilateral anterior thoracotomy incision for treating extensive thoracic aortic disease was described by Kouchoukos et al. in 2001 and by Doss et al. in 2003. We describe the utility of this approach for treating aortic arch aneurysm with Stanford type B aortic dissection.

Ten-Year Experience of Coronary Endarterectomy for the Diffusely Diseased Left Anterior Descending Artery

BACKGROUND Coronary endarterectomy (CE) is a surgical option for a diffusely diseased coronary artery. This study evaluated the clinical and angiographic outcomes of CE for a diffusely diseased left anterior descending artery (LAD) using the internal thoracic artery (ITA). METHODS From September 2004 to September 2014, 188 patients (163 men; mean age, 66.1 years) underwent coronary artery bypass grafting with CE for a diffusely diseased LAD. Forty patients (21.3%) had unstable angina, and 55 (29.3%) were at Canadian Cardiovascular Society class 3 or 4. Mean ejection fraction was 0.55. Endarterectomy was performed under direct vision through a long arteriotomy in all patients. Angiographic evaluation was performed before discharge and at 1 year after the operation. RESULTS Mean arteriotomy length was 6.1 ± 1.8 cm. The endarterectomized LAD was reconstructed using the left ITA in 179 (95.2%) or the right ITA in 9 (4.8%). The operation was conducted off pump in 185 patients (98.4%). The 30-day mortality was 1.1%. Perioperative myocardial infarction occurred in 17 patients (9.0%). The patency rate of the ITA and LAD at early postoperative and follow-up angiography was 91.6% and 96.6%, respectively. Optical coherence tomography performed in 8 patients revealed that the endarterectomized LAD was completely endothelialized and that the surface of the reconstructed lumen had become homogeneous within 1 year after the operation. The median follow-up period was 5.8 years. At 5 years, freedom from all-cause death was 89.3% ± 2.4% and freedom from major adverse cardiac and cerebrovascular events was 74.0% ± 3.3%. CONCLUSIONS CE for a diffusely diseased LAD using the ITA provides satisfactory clinical outcomes with favorable rates of angiographic patency.

Comparison of aortic arch repair using the endovascular technique, total arch replacement and staged surgery

OBJECTIVES We evaluated the operative and long-term outcomes of various approaches for aortic arch repair. METHODS A total of 436 consecutive patients who underwent aortic arch repair from January 2001 to March 2016 in our centre were evaluated. Of these, 276 underwent conventional total arch replacement (TAR), and 118 underwent thoracic endovascular repair (TEVAR). The remaining 42 patients underwent staged thoracic endovascular repair (STEVAR). A total of 72 patients in the TEVAR group were matched to 72 patients who underwent open surgery including TAR or STEVAR by using propensity score analysis. RESULTS Surgical outcomes showed shorter ICU and hospital stay in the TEVAR group ( P  < 0.001 and P  < 0.001, respectively). The 30-day mortality and neurologic dysfunction showed no significant difference among the three groups (2.8 and 5.4% in TAR group, 1.7 and 8.5% in TEVAR group and 0 and 2.4% in STEVAR group; P  = 0.500 and P  = 0.297, respectively). Long-term survival was not significantly different among the three groups (78% in TAR group, 67% in TEVAR group and 81% in STEVAR group at 5 years; P  = 0.123). Freedom from aortic reintervention was lower in the TEVAR group than in other groups (98% in TAR, 92% in TEVAR and 97% in STEVAR at 5 years, P  = 0.040). CONCLUSIONS Operative outcomes showed no significant differences between the groups except for early recovery after TEVAR. Long-term survival was similar between groups; however, TEVAR had inferior reintervention free rate.

Surgical Treatment of Patent Multilocular Saphenous Vein Graft Aneurysms After Coronary Artery Bypass Grafting.

A 75-year-old man with previous mitral valve plasty and saphenous vein–posterolateral branch grafting 19 years earlier complained of 48-hour frequent resting chest pain. Computed tomographic images demonstrated partially thrombosed 34 41mm, 34 38mm, and 38 41mmmultilocular aneurysmswithin the body of the saphenous vein graft to the posterolateral artery and coronary angiography revealed three-vessel disease and severely degenerated multilocular saphenous vein graft aneurysms with diminished graft flow (Fig. 1 and Supplementary Video V1). Aneurysm ligation and excisionwith simultaneous revascularizationwas performed (Fig. 2 and Supplementary Video V2).

Causes of repair failure for degenerative mitral valve disease and reoperation outcomes

OBJECTIVES This study aimed to evaluate the causes of initial mitral valve (MV) repair failure, the details of reoperation and the long-term outcomes of mitral valve re-repair (Re-MVP). METHODS We retrospectively reviewed 86 patients who underwent reoperation after MV repair for MR due to degenerative disease from October 1991 to December 2015. First, we analysed the initial MV repair data, causes of MV repair failure, reoperation data and long-term outcomes including survival. Second, the patients were classified into 2 groups based on valve related failure or procedure related failure , and the differences between the groups were analysed. RESULTS Leaflet prolapse at the initial operation affected the bilateral leaflets in 37 (43%) patients, the anterior leaflet in 30 (35%) patients and the posterior leaftlet in 19 (22%) patients. Median duration from first operation to reoperation was 47.5 (interquartile range 4.8-85.8) months. Reoperation indication included recurrent mitral regurgitation alone in 59 patients, haemolysis combined with recurrent mitral regurgitation in 15 patients, infectious endocarditis combined with recurrent mitral regurgitation in 8 patients, mitral stenosis in 2 patients and left ventricular pseudoaneurysm in 2 patients. The cause of MV repair failure was valve-related in 61 (71%) patients, procedure-related in 20 (23%) patients and both in 5 (6%) patients. Re-MVP was successful in 23 (27%) patients. Re-MVP was more common in patients with procedure-related failure, which occurred earlier than valve-related failure. Freedom from all-cause death was significantly better after Re-MVP. The 5-year freedom from reoperation after Re-MVP was 95.7%. CONCLUSIONS Re-MVP was more common in patients with procedure-related failure, which occurred earlier than valve-related failure. Durability of re-repaired MVs and survival of re-repaired patients were acceptable.

Stonehenge technique is associated with faster aortic clamp time in group of minimally invasive aortic valve replacement via right infra-axillary thoracotomy

BackgroundTrans-right axillary aortic valve replacement (TAX-AVR) remains uncommon. We developed a special method to pull the heart closer to the right chest wall to make the surgery as easy and safe as aortic valve replacement via median sternotomy. Because the retraction sutures lifting the ascending aorta and aortic root are arranged circularly around the wound, we named this technique “Stonehenge technique”.MethodsWe examined 47 patients who underwent aortic valve replacement through a small right infra-axillary thoracotomy as the initial surgical therapy. These patients were divided into two groups: the conventional TAX-AVR group that underwent AVR via the conventional small right axillary incision approach (n = 20) and the TAX-AVR with SH group that underwent AVR with the Stonehenge technique (n = 27).ResultsThe aortic cross-clamp and the extracorporeal circulation time were significantly shorter in the TAX-AVR with SH group than in the conventional TAX-AVR group (conventional TAX-AVR group: 125.5 ± 47.9; TAX-AVR with SH group: 96.0 ± 14.0, p = 0.004, and conventional TAX-AVR group: 163.8 ± 55.9; TAX-AVR with SH group: 140.0 ± 16.8, p = 0.04).ConclusionThe outcomes of this technique depend on the site of the retraction sutures in the opened pericardium, direction of pull, amount of force applied, and precautions taken. If performed correctly, the ascending aorta and the root can be pulled from the wound to within the surgeon’s fingers’ reach, thereby reducing aortic cross-clamp and extracorporeal circulation times in group of minimally invasive aortic valve replacement via right infra-axillary thoracotomy.

Thoracic Endovascular Aortic Repair for Pseudoaneurysm after Interrupted Aortic Arch Repair

Here we describe the case of a 33-year-old woman who was diagnosed with interrupted aortic arch (IAA) type A and who underwent radical surgery in her infancy. She developed a 42-mm anastomotic pseudoaneurysm in the distal aortic arch. We decided to perform thoracic endovascular aortic repair because of the patient’s special request to avoid open surgery. We selected a reversed taper-type leg stent graft for the iliac artery and successfully implanted it without problems. However, the long-term outcomes of the stent graft in young people remain unclear, and careful regular follow-up for a long period is mandatory.