Rapid anticalcification treatment for glutaraldehyde-fixed autologous tissue in cardiovascular surgery.

BACKGROUND: Glutaraldehyde (GA)-fixed autologous tissues, including the pericardium, are widely used as patches and valve substitutes in cardiovascular surgery. However, GA treatment causes tissue calcification. No rapid anticalcification method has been established for use during surgery. Here, we aimed to establish a rapid anticalcification method using ethanol, as has already been demonstrated for bioprosthetic valves. METHODS: Thoracic aorta tissues were first fixed with GA for 3 min and then treated with ethanol for 0 (group 2), 10 (group 3), 20 (group 4), and 30 (group 5) min; untreated tissues (group 1) served as the control. The treated tissues were subdermally implanted into 3-week-old male Wistar rats and kept in place for 28 days. The calcification in each explant was semiquantitatively evaluated by annotating and measuring the area using virtual slides, and the data obtained were statistically analyzed. RESULTS: Semiquantitative analysis revealed that calcification of the implants from the untreated group (group 1; P = 0.0014) and groups 4 (P = 0.0014) and 5 (P = 0.0031) was significantly lower than that of implants from group 2. Moreover, implants from group 3 showed a tendency toward decreased calcification, although it was not significant (P = 0.0503). CONCLUSIONS: A rapid ethanol treatment prevents calcification of GA-fixed tissues in a rat model of subdermal implantation. This method may facilitate effective and rapid anticalcification of autologous tissues for use during cardiovascular surgery.

Low hematocrit levels: a risk factor for long-term outcomes in patients requiring prolonged mechanical ventilation after cardiovascular surgery. A retrospective study.

While low-risk patients who undergo elective surgery can tolerate low hematocrit levels, the benefits of higher hematocrit levels might outweigh the risk of transfusion in high-risk patients. Therefore, this study aimed to evaluate the effects of perioperative hematocrit levels on mortality in patients requiring prolonged mechanical ventilation (PMV) after a cardiovascular surgery. This single-center retrospective cohort study was conducted on 172 patients who underwent cardiovascular surgery with cardiopulmonary bypass or off-pump coronary artery bypass grafting and required PMV for ≥72 hours in the intensive care unit (ICU) from 2008 to 2012 at the Yokohama City University Medical Center in Yokohama, Japan. Patients were classified according to hematocrit levels on ICU admission: high (≥30%) and low (<30%) groups. Of 172 patients, 86 were included to each of the low-hematocrit and high-hematocrit groups, with median hematocrit levels (first to third quartiles) of 27.4% (25.4%-28.7%) and 33.0% (31.3%-35.5%), respectively. The difference in survival rates was significant between the two groups using the log-rank test (HR 0.55, 95% CI 0.32 to 0.95, p=0.033). Cox regression analysis revealed that ≥30% increase in hematocrit levels on ICU admission was significantly associated with decreased long-term mortality (HR 0.40, 95% CI 0.20 to 0.80, p=0.0095). Lower hematocrit levels on ICU admission was a risk factor for increased long-term mortality, and higher hematocrit levels might outweigh the risk of transfusion in patients requiring PMV after a cardiovascular surgery.

Priming and replenishment in cardiopulmonary bypass with hydroxyethyl starch 130/0.4 decreases fluid overbalance without renal dysfunction or bleeding in adult valve surgery.

The best priming and replenishment solution in cardiopulmonary bypass remains unknown, and the efficacy and drawbacks of artificial colloid are controversial. We retrospectively compared consecutive patients undergoing elective adult valve surgery in cases wherein cardiopulmonary bypass was primed and replenished with hydroxyethyl starch 130/0.4 (n = 12) or crystalloid solution (n = 11). The fluid overbalance during cardiopulmonary bypass was much lower in the hydroxyethyl starch 130/0.4 group (mean ± standard deviation, + 95 ± 1241 mL) than in the crystalloid solution group (+ 2921 ± 1984 mL) (P < 0.001). Renal function, intraoperative and postoperative bleeding, and blood products did not deteriorate with the use of hydroxyethyl starch 130/0.4. The postoperative intubation time was shorter in the hydroxyethyl starch 130/0.4 group (16.0 ± 2.6 h) than in the crystalloid solution group (18.7 ± 2.6 h) (P = 0.018). Although prospective randomized trials are needed to verify our findings, the impact of fluid balance differences requires serious consideration.

De-airing an open stent graft to potentially reduce spinal cord injury.

We have occasionally observed a bubble leaving the suture line of an open stent graft; hence, we hypothesized that de-airing an open stent graft could potentially reduce spinal cord injury. Postoperative computed tomography often showed residual air in thoracic aortic aneurysms, confirmed by the presence of a certain amount of air in an open stent graft in a dry lab. We filled CO2 in the sterilized package of an open stent graft and subsequently filled it with saline, which absorbed the CO2 and entered into the gap of the graft. The clinical benefit of de-airing an open stent graft to reduce the incidence of spinal cord injury needs to be evaluated.

Efficacy of Glutaraldehyde-Treated Leaflets for Mitral Valve Repair to Treat Active Infective Endocarditis: A Case Report.

We report the use of glutaraldehyde (GA) in a case of valve repair for mitral valve prolapse associated with active infective endocarditis. GA scrubbed at the site of infection decontaminates and reinforces infected fragile tissue, avoids excessive debridement, and strengthens the edges of valve leaflets to facilitate suturing.

Pitfalls for the "Sandwich technique" via a right ventricular incision to repair post-infarction ventricular septal defects.

BACKGROUND: We have reported "sandwich technique," via a right ventricular incision, to treat a post-infarction ventricular septal defect (VSD). This technique involves the placement of patches on both the left and right sides of the septum, pinching the VSD sealed with surgical adhesive between the two patches. In this study, we analyzed factors influencing 1-year mortality to determine the pitfalls in our procedure. METHODS: We evaluated 24 consecutive patients with post-infarction VSD who underwent the "sandwich technique" via a right ventricular incision. One-year survival and major residual leak were used as the criteria for the analysis of survival and technical success, respectively. In protocol 1, clinical variables were evaluated as predictors of one-year mortality. In protocol 2, surgical techniques were evaluated as predictors of major residual leak, which was found to be related to one-year mortality in protocol 1. RESULTS: In protocol 1, the one-year mortality was higher in patients with major residual leak (75 %, 3/4) than in those without (15 %, 3/20) (p = 0.035). In protocol 2, the patients with major residual leak had smaller patches than those without (41.9 ± 3.8 vs. 47.8 ± 4.8 mm, p = 0.031) and a smaller size difference between the patches and the VSD (22.5 ± 6.5 vs. 30.0 ± 5.7 mm, p = 0.028). CONCLUSION: For the "sandwich technique" via a right ventricular approach to treat post-infarction VSD, the choice of patch size according to VSD size is an important variable for reducing major residual leak.

Pathophysiology and Surgical Treatment of Type A Acute Aortic Dissection.

Objectives: We report the pathophysiology and treatment results of type A acute aortic dissection from our 20-year experience. METHODS: We studied 673 patients with type A acute aortic dissection who underwent initial treatment from 1994 through July 2014. We divided these patients into two groups. The former group comprised 448 patients from 1994 through 2008, and the latter group comprised 225 patients from 2009 onward, when the current strategy of initial treatment and surgical technique including the early organ reperfusion therapies were established. Results: Women were significantly often presented than men in patients over 60 years of age. Thrombosed-type dissection accounted for more than half in patients over 70 years, and significantly often complicated pericardial effusion and cardiac tamponade than patent type. Malperfusion occurred in 26% of patients. Central repair operations were performed in 579 patients. In-hospital mortality for all patients was 15%, and for the patients who underwent central repair operations was 10%. Former period of operation, malperfusion, and preoperative cardiopulmonary arrest were significant risk factor of in-hospital death. Preoperative left main trunk (LMT) stents were placed in eight patients and superior mesenteric artery (SMA) intervention was performed in five, they were effective to improve the outcome. From 2009 onward, in-hospital mortality was 5.0% and there was no significant risk factor. Conclusion: Surgical results of type A acute aortic dissection were dramatically improved in the past 20 years. Early reperfusion strategy for the patients with malperfusion improved the outcomes. (This article is a translation of Jpn J Vasc Surg 2015; 24: 127-134.).

Heparin-Induced-Thrombocytopenia Causing Massive Aortic Thrombosis after Ascending Aortic Replacement for Type A Acute Aortic Dissection.

A 77-year-old woman underwent emergency ascending aortic replacement for type A acute aortic dissection. Fifteen days after the operation, she had motor and sensory disturbances in the lower limbs. Computed tomography revealed multiple aortic thrombi and disrupted blood flow in the right external iliac and left common iliac arteries. She underwent an emergency thrombectomy for acute limb ischemia. Because heparin-induced-thrombocytopenia (HIT) was suspected to have caused the multiple aortic thrombi, we postoperatively changed the anticoagulant therapy from heparin to argatroban. Seventeen days after the first operation, gastrointestinal bleeding developed, and the patient died of mesenteric ischemia caused by HIT. Arterial embolization caused by HIT after cardiovascular surgery is a rare, but fatal event. To avoid fatal complications, early diagnosis and early treatment are essential. Use of a scoring system would probably facilitate early diagnosis.

"Pouch Technique" Makes Proximal Anastomosis of Free Internal Thoracic Artery Graft to Ascending Aorta Easy and Safe in Coronary Artery Bypass Surgery.

PURPOSE: The proximal anastomosis of free right internal thoracic artery to ascending aorta is technically difficult when the caliber is not enough. METHODS: We incise the proximal stump of the graft longitudinally for 10 mm. One side of start point of longitudinal incision is sewn to the end point of incision by 7-0 polypropylene. The folded sideline (5 mm length) is then closed with a running suture, then formation of pouch like anastomotic end is accomplished. RESULTS: We used this technique in consecutive 34 patients who underwent coronary artery bypass surgery including revascularization to circumflex arteries. Postoperative angiography revealed 97% patency. It does not need another graft material like saphenous vein or radial artery, and possible not only in on pump surgery but also in off pump. CONCLUSION: This new "Pouch technique" will make it easy to use right internal thoracic artery as a free graft in coronary artery bypass surgery.

"Sandwich Technique" via a Right Ventricle Incision to Repair Postinfarction Ventricular Septal Defects.

BACKGROUND: Residual shunting and mortality are problems associated with the current surgical repair techniques for postinfarction ventricular septal defects (VSD). We developed the "sandwich technique" via a right ventricle incision and assessed the surgical outcome of 13 years of experience with this technique. METHODS: Between June 2001 and March 2013, 25 consecutive patients with postinfarction VSD underwent surgical repair using this technique. This technique includes the following: Application of direct ultrasonography to the right ventricular (RV) wall enables the surgeon to visualize the lesion, perform an appropriate incision into the RV, and perform a trabecular resection. One patch is placed on the left ventricular (LV) side and the other on the RV side of the VSD. The VSD is sealed with gelatin-resorcin-formalin (GRF) glue between the two patches. RESULTS: Thirty-day mortality was 0% (0/25 case). A postoperative major shunt occurred in three patients (12%, 3/25) and two of them required reoperation (8%, 2/25). Hospital mortality was 28% (seven patients). Mean follow-up period was 4.2 ± 3.7 years. The overall survival at one, five, and 10 years was 71 ± 9%, 65 ± 10%, and 56 ± 12%, respectively. There was no cardiac death during follow-up in the patients who survived for six months after the surgery. No tissue degeneration related to GRF glue was noted. CONCLUSION: The "sandwich technique" via a right ventricle incision results in a low incidence of postoperative leak and good short- and mid-term survival.

A stepwise aortic clamp procedure to treat porcelain aorta associated with aortic valve stenosis and hemodialysis.

A 62-year-old man was referred for an aortic-valve surgery because of severe aortic stenosis. Thirty years ago, he had undergone a mitral valve commissurotomy and after 9 years, the valve had been replaced by a mechanical valve. He had been undergoing hemodialysis for the past 8 years. A computed tomographic (CT) scan of the chest and abdomen showed a dense circumferential calcification in the wall of the entire thoracic and abdominal aorta, pulmonary artery, and left and right atrium. A conventional aortic-valve replacement was performed. To avoid an embolic event, a "stepwise aortic clamp" procedure was attempted and involved the following: (1) brief circulatory arrest and aortotomy during moderate hypothermia; (2) balloon occlusion at the ascending aorta during low-flow cardiopulmonary bypass (CPB); (3) endoarterectomy by using an ultrasonic surgical aspirator to enable aortic cross-clamping; and (4) a cross-clamp reinforced with felt and full-flow CPB. The patient recovered without any thromboembolic events. Using this procedure to treat a porcelain aorta seemed to reduce the time limit and reduced the risk of brain injury during cardiac surgery.

Off-pump multilayered sutureless repair for a left ventricular blowout rupture caused by myocardial infarction in the second diagonal branch territory.

A left ventricular (LV) free wall rupture is a highly lethal condition. A 78-year-old female, who collapsed while riding a bike, was admitted to our emergency service 7 days after experiencing chest pain. During admission, she had cardiopulmonary arrest. Though cardiopulmonary resuscitation was successful, computed tomography (CT) showed cardiac tamponade. Emergency surgery was then performed. Pericardiotomy revealed a postinfarction blowout rupture of an aneurysm (2 × 3 × 1 cm) on the anterolateral wall of the LV. The top of the aneurysm had a 2-mm wide blowing blood column. Intra-aortic balloon pumping was initiated. An off-pump multilayered sutureless repair using squares of collagen fleece with fibrinogen-based impregnation (i.e., TachoComb) and gelatin-resorcin-formalin glue (GRF glue) was performed. Postoperative coronary angiography revealed occlusion of the second diagonal branch. The patient was free from re-rupture or aneurysm enlargement. An LV blowout rupture, which was caused by myocardial infarction with a limited tear and necrotic area at the second diagonal branch territory, was successfully treated with an off-pump multilayered sutureless repair by using a TachoComb and GRF glue patch. The thickness of the hemostatic material seemed to help control the bulging of the aneurysm and to prevent further LV aneurysm enlargement and re-rupture.

A case report of pulmonary thromboendarterectomy for chronic thromboembolism in a patient with protein C deficiency.

The patient was a 41-year-old female with chronic thromboembolism. She was admitted to an affiliated hospital with exertional dyspnea, leg swelling, and hemoptysis, and she was treated medically with tissue plasminogen activator and warfarin therapy. When transferred to our hospital, she was oxygen-dependent with severe dyspnea. A pulmonary arteriogram showed occlusion and stenosis of the pulmonary arteries. Cardiac catheterization revealed marked pulmonary hypertension. The lung perfusion scintigram showedmultiple defects in the right and left lungs. Preoperative laboratory data showed a markedly decreased protein C antigen level. Magnetic resonance angiography showed that a myoma uteri compressed the pelvic vein and that she had deep vein occlusion of the left leg. After the administration of an epoprostenol infusion and the insertion of an inferior vena cava filter, she underwent an operation. Under deep hypothermia, the bilateral pulmonary artery was opened and an endarterectomy was performed during intermittent circulatory arrest. After surgery, her pulmonary vascular resistance was in the normal range. Her New York Heart Association functional classification changed from class IV to class I. She has been in good condition for 7 years since the surgery.

Occupational true aneurysm of the ulnar artery: a case report of hypothenar hammer syndrome.

A 32-year-old male patient was admitted to the hospital with a pulsing mass of the right palm. He was an electrical construction engineer who frequently used a screwdriver. Computed tomography (CT) examination revealed a 22- × 30-mm saccular aneurysm of the right ulnar artery. The ulnar artery aneurysm was resected, and we could perform direct anastomosis of the ulnar artery. The dilated true aneurysm was compatible with a traumatic origin. A postoperative enhanced CT examination showed smooth reconstruction of the palmar arch. An occupational true aneurysm of the ulnar artery could be treated by resection and direct anastomosis.

Surgical repair of postinfarction ventricular septal defects-2013 update.

Treatment for postinfarction ventricular septal defect has been improving for several decades. Aggressive resection of the infarcted myocardium (infarctectomy and closure technique) and preserving infarcted myocardium (infarct exclusion technique) have been technically modified. Recent improvement includes use of surgical glue, using an additional patch for infarct exclusion, septal exclusion, sandwich technique via right or left ventricular approach, and endovascular repair. This field still has room for cardiac surgeons to improve surgical strategy and technique.