Experimental right heart bypass operations have influenced the evolution of current application of the Fontan procedure. In this review, we summarize the evolution and progress of the experimental Fontan operation (FO) and discuss the questions raised so far. The evolution and progress of the experimental FO is analyzed in this review by collecting data retrieved from English literature research. The establishment of Fontan circulation on an experimental animal model is extremely difficult and until today, a chronic experimental model has never been described. Computational fluid dynamics (CFD) has played a significant role in the investigation of the hemodynamic characteristics of the FO and has been applied to the design and integration of the procedure. CFD was also employed to evaluate the performance of assisted Fontan circulation. Accumulated experience from the experimental studies and clinical practice, in combination with the cooperation of different fields in medicine and positive sciences, are definitely expected to help the evolution furthermore.

View full abstract

Background: Oxidative stress due to reactive oxygen species (ROS) is thought to play a considerable role in ischemia/reperfusion (I/R) injury that impairs cardiac function. The present study examined oxidative damage in I/R injury and investigated the correlation between oxidative stress and impaired cardiac function after I/R injury of the isolated rat heart.
Methods: Hearts isolated from male Sprague-Dawley rats were mounted on a Langendorff apparatus. Hearts arrested using St. Thomas cardioplegic solution and then they were reperfused. The hearts were divided into three groups depending on the frequency (0-2) of I/R. After I/R, left ventricular developed pressure (LVDP), left ventricular end-diastolic pressure (LVEDP), positive maximum left ventricular developing pressure (max LV dP/dt) and coronary flow (CF) were measured. Creatine kinase (CK) was measured in the coronary effluent and 8-hydroxy-2’deoxyguanosine (8OHdG), a marker of oxidative DNA damage, was measured. Adenosine triphosphate (ATP) was measured from frozen myocardial tissue after experiment.
Results: We immunohistochemically demonstrated and quantified levels of 8-OHdG after I/R injury of the heart. The frequency of I/R injury and cardiac dysfunction significantly and negatively correlated. The ATP products were similar among the three groups. The incidence of ventricular arrhythmias was not by affected oxidative stress.
Conclusion: The frequency of I/R injury had more of an effect on 8-OHdG products and on impaired cardiac function with less myocyte damage than ischemic duration within 30 minutes of ischemia.

View full abstract

Objectives: Reduction of cognitive function is a possible side effect after cardiac surgery. We investigated the effect of transfemoral versus conventional aortic valve replacement on cognitive performance early after surgery.
Methods: 50 patients with transfemoral, catheter-based aortic valve implantations were compared to 50 patients with conventional surgical aortic valve replacement. Six neuropsychological subtests from the Syndrom Kurz Test and Alzheimer’s Disease Assessment Scale were performed preoperatively and on the third postoperative day in a double blind fashion. To assess the overall cognitive function and the degree of cognitive change across all tests after surgery we combined the six test-scores by principal component analysis.
Results: The preoperative (S_pre), as well as postoperative (S_post) overall cognitive function scores, were not significantly different between the groups and showed deterioration within both groups (S_pre conv. 0.2 ± 1.0 vs S_post conv. -0.6 ± 1.1, p <0.0005 and S_pre transfem. -0.2 ± 1.0 vs S_post transfem. -0.6 ± 1.1, p = 0.002). This decline (S_pre -S_post) was not associated with the type of operation (p = 0.1).
Conclusion: Transfemoral aortic valve implantation has no cerebroprotective advantage since it leads also to an early postoperative decline of neuropsychological abilities, which is comparable to conventional aortic valve replacement.

View full abstract

Purpose: to assess the early hemodynamic changes after elective mitral valve replacement (MVR) in patients with severe and mild pulmonary arterial hypertension (PAH).
Methods: a total of 45 consecutive patients, who were candidate for elective MVR, were enrolled in this prospective observational study. Patients were divided into two groups based on the absence (group A, 20 patients) or presence (group B, 25 patients) of severe pulmonary artery hypertension (PAH) defined as systolic pulmonary artery pressure ≥50 mmHg measuring by catheterization. MVR was performed using standard cardiopulmonary bypass (CBD) technique. The hemodynamic and arterial blood gas assessments were carried out at baseline before the induction of general anesthesia, in the operating room immediately after MVR, and then continued after stabilization of hemodynamic status with 2 hr interval up to 24 hours.
Results: The mean CPB and aortic cross-clamp times were similar in two groups (95.3 ± 49.5 and 61.8 ± 36.3 minutes in group A and 103.1 ± 34.7and 61.9 ± 20.0 minutes in group B). In group A, the mean PAP showed an increase immediately after the operation (from 40.4 ± 7.3 to 43.10 ± 6.2 mmHg) and then decreased significantly to 32.5 ± 3.9 mmHg (P <0.05). In group B, the mean PAP showed no significant reduction immediately after MVR, but it decreased significantly below the range of severe PAP over the first 24 hours.
Conclusion: MVR is safe and effective even in patients with severe PAH. The anesthetic technique and postoperative cares can be useful in improving the outcome in such patients.

View full abstract

Purpose: This study examines the efficacy of warfarin in preventing ischemic stroke due to paroxysmal atrial fibrillation (PAF) after coronary artery bypass grafting (CABG).
Methods: Postoperative PAF occurred in 151(33.5%) of 447 patients undergoing conventional CABG. The patients were divided into two groups: group I consisting of 93 patients administered two types of antiplatelet agents and group II consisting of 58 patients treated with a single antiplatelet agent and warfarin. We compared the two groups in terms of CHADS2 score, incidence of ischemic stroke, and independent risk for stroke associated with post-CABG PAF.
Results: The group I CHADS2 score (2.24 ±1.67) was significantly lower than the group II score (2.64 ± 1.22), p = 0.0452. However, 12 patients in group I (12.9%) suffered postoperative ischemic stroke, a rate significantly higher than that of group II (1 patient, 1.7%; p = 0.0173). Any recurrence of PAF or atrial fibrillation with bradycardia was assessed at the time of stroke onset. Logistic regression analysis showed that the absence of warfarin therapy constituted a risk factor for post-CABG stroke associated with PAF (Odds 13.04, p = 0.027).
Conclusion: Warfarin therapy administered concomitantly with an antiplatelet agent dramatically reduced the incidence of ischemic stroke associated with postoperative PAF.

View full abstract

Purpose: Primary spontaneous pneumothorax is believed to result from blebs, or from other abnormalities of the pleural surface. There is no consensus as to whether a change in weather conditions can precipitate spontaneous pneumothorax. The aim of the present study was to investigate the influence of weather conditions on the onset of primary spontaneous pneumothorax.
Methods: The case histories of 1051 inpatients with primary spontaneous pneumothorax treated at Nissan Tamagawa Hospital between January 2006 and December 2011 were analyzed retrospectively. Data on weather conditions were collected daily throughout the 6-year period. The data were analyzed to determine differences in weather conditions between days on which primary spontaneous pneumothorax occurred and those on which it did not.
Results: Primary spontaneous pneumothorax occurred on 819 (37.3%) of 2191 study days. On days before and the day of primary spontaneous pneumothorax onset, the difference in mean atmospheric pressure was 0.6 hPa lower than on days in which no primary spontaneous pneumothorax occurred. This difference was statistically significant (P = 0.015). There was no statistical difference in mean, maximum, and minimum temperature, hours of sunshine, amount of precipitation, and mean and minimum humidity between days with and those without primary spontaneous pneumothorax.
Conclusion: This largest study of the literature showed decreased atmospheric pressure might play an important role in the occurrence of primary spontaneous pneumothorax.

View full abstract

Purpose: Surgical correction of the partial anomalous pulmonary venous connection (PAPVC) draining into the superior vena cava (SVC) has been associated with sinus node dysfunction and venous return obstruction, postoperatively. We present the results of our lateral cavoatriotomy approach with little modifications to avoid injury to the sinus node and its artery.
Methods: 32 patients who underwent surgical repair of PAPVC to SVC with modified lateral cavoatriotomy in our clinic between January 2003 and January 2009 were evaluated retrospectively.
Results: Median age was 6 years (2-32 years). The mean follow-up time was 65.8 ± 23.7 months (36-111 months). There were no early or late deaths. No patients required reoperation. New onset of arrhythmia had developed in two patients and resolved before hospital discharge. Stenosis of the SVC in one patient had developed 11 months after the operation and was treated with balloon angioplasty, successfully. No sinus node dysfunction or venous return obstruction was detected in their last follow-up.
Conclusion: Cavoatrial incision for repair of PAPVC to SVC may become a safer surgical technique with some modifications.

View full abstract

A 32-year-old man was urgently referred to our hospital with severe tricuspid insufficiency following a car accident. The completely flail anterior leaflet, due to the rupture of the papillary muscles, was revealed by a two-dimensional transthoracic echocardiography. In the operation, we also detected a tear on the anterior leaflet and the rupture of numerous chordae tendineae of the other leaflets. Valve repair was not considered feasible, therefore the tricuspid valve was replaced with a 31 mm mechanical prosthesis. The patient's recovery from surgery was uneventful, and he was discharged on the seventh postoperative day.

View full abstract

We here present the case of a 35-year-old man with mitral valve paravalvular abnormal tunnel with mitral regurgitation caused by anterior chest trauma. The abnormal tunnel is between left ventricular and left artrial. We sutured the tunnel with a patch from the left atrial side. Meanwhile, we performed the mitral valve annuoplasty because of the mitral regurgitation accompanied. The postoperation and the 12th month follow up were uneventful.

View full abstract

We present a case of spontaneous retroperitoneal hemorrhage secondary to anticoagulant therapy. A 41-year-old woman who underwent aortic valve replacement due to infective endocarditis 2 months ago was admitted for evaluation of dizziness and fatigue. Physical examination revealed the abdomen to be distended. Blood work showed a hemoglobin 4.5 and INR 3.5. Abdominal CT showed a huge intra-abdominal hematoma with right internal iliac artery rupture. In abdominal aortic angiography, rupture of right internal iliac artery was confirmed and treated with embolization. Bleeding stopped after embolization, but she developed acute renal failure secondary to a huge hematoma. On POD#4, she underwent a laparotomy and the hematoma was evacuated. The patient had an uneventful recovery and was discharged from the hospital with no further bleeding episodes.

View full abstract

A 56-year-old man had left nephrectomy and resection of a cavoatrial tumor thrombus under a cardiopulmonary bypass assist for left renal cell carcinoma. An intraoperative bipolar temporary epicardial atrial pacing wire was removed on postoperative day 8. The patient collapsed on postoperative day 15. Emergent transthoracic echocardiography and computed tomography scanning with contrast media detected cardiac tamponade. The three-dimensional volume-rendering images from the multislice computed tomography scan demonstrated bleeding from the aortic root. Upon emergency operation, active arterial bleeding from the aortic root distal to the sites of cannulation and cardioplegia was confirmed, and hemostasis with sutures was completed. It is well known that the intraoperative temporary epicardial pacing wire can cause bleeding or arrhythmia, especially when the wire is being removed. However, bleeding usually occurs from the inserted epicardial point of the pacing wire soon after removal of the wire. To our knowledge, this late bleeding complication of the pacing wire is a previously unreported serious iatrogenic complication after cardiac surgery.

View full abstract

An 82-year-old-man with a previous history of atrial fibrillation was admitted with acute limb ischemia. Emergent embolectomy was performed, but after the operation, the patient suffered from recurrent ischemic pain. Peripheral angiography revealed thrombosis of the distal popliteal artery due to pre-existing peripheral arterial occlusive disease. Bypass surgery of the popliteal artery and posterior tibial artery was then performed. Although peripheral blood flow was restored after the operation, he suffered from compartment syndrome the next day. The patient was treated with an emergent bed-side fasciotomy using a small incision, achieving full recovery of blood flow to the distal artery. The wound closed secondarily without surgical closure. In a patient with peripheral arterial occlusive disease, fasciotomy should be performed at a lower compartment pressure due to a lack of peripheral perfusion pressure. Emergent small incision fasciotomy was effective in this patient with an acute compartment syndrome and an ischemic limb.

View full abstract

An infected aortic arch aneurysm is a rare but life-threatening condition. Moreover, surgical treatment for patients with severe calcified aorta is challenging and needs a well-planned strategy. We report a patient with an infected aortic arch aneurysm concomitant with severe calcification of the aorta in whom good results were obtained with open stent grafting in combination with a trifurcated graft.

View full abstract

Background: Currently, thoracoscopic surgery is replacing thoracotomy for an ever increasing number of indications, even in pediatric surgery. However, there are few reports describing thoracoscopic plication (TP) for diaphragmatic eventration in children, particularly in neonates. We report a case of TP under single-lung ventilation in a neonate with diaphragmatic eventration.
Case Report: A 10-day-old boy was referred for surgical management of right diaphragmatic eventration. Birth was at term, following an uncomplicated pregnancy and delivery. Shortness of breath, labored respiration and chest retraction presented soon after birth, necessitating mechanical ventilation. Chest radiography and computed tomography revealed an elevated right hemidiaphragm. Attempted weaning off mechanical ventilation failed with persistence of respiratory symptoms, requiring nasal directional positive airway pressure. However, because there was no resolution of symptoms, TP was performed using a 3 port technique under single-lung ventilation on day 17 of life. The postoperative course was excellent with complete resolution of respiratory symptoms with no recurrence for 9 months.
Conclusion: To the best of our knowledge, this is the youngest case of TP for diaphragmatic eventration performed under single-lung ventilation. TP is safe, effective and minimally invasive and should be considered actively for the treatment of symptomatic diaphragmatic eventration even in neonates.

View full abstract

Patients with Sjögren’s syndrome frequently have pulmonary involvement, but the involvement of nodular pulmonary lesions, including pulmonary amyloidosis, is rare. Most cases of pulmonary amyloidosis involve multiple nodules; solitary pulmonary nodular amyloidosis, as an associated condition of Sjögren’s syndrome, is very rare.
In our report, we present the case of an 80-year-old female with Sjögren’s syndrome who was incidentally found to have a small solitary pulmonary nodule. The nodule showed high fluorodeoxyglucose uptake and contained areas of calcification. Because the probability that the nodular lesion was malignant could not be excluded, the tumor was excised using a thoracoscopic procedure; the final diagnosis was pulmonary nodular amyloidosis.
Although most cases of pulmonary amyloidosis involve multiple nodules, amyloidosis should be considered in the differential diagnosis for a solitary pulmonary nodule in patients with Sjögren’s syndrome.

View full abstract

Chondromyxoid fibroma (CMF) is a rare, benign cartilaginous tumor, comprising less than 1% of primary bone tumors, and usually occurs in the metaphysis of a long tubular bone around the knee. We report a rare case of CMF of the rib. The patient was a 25-year-old man who visited the hospital for left upper back pain. Roentgenography revealed an 8-cm mass in the left upper lung field; computed tomography revealed a large multicystic tumor with aneurysmal bone cyst (ABC)-like features in the posterior mediastinum. ABCs are also a rare benign tumor representing 2.5% of primary bone tumors, and most of ABCs are located in the metaphysis of long bones and vertebrae. To the best of my knowledge, there is no report of CMF with secondary ABC of the rib. We performed total resection of the tumor. Complete tumor resection may be the best treatment option for a cure.

View full abstract

Here, we report a case of hepatoblastoma metastasis to the left pulmonary artery which was resected by left lingular segmentectomy plus left lower lobectomy in 5-year-old girl. She had previously undertaken right upper lobectomy and multiple lung partial resections on bilateral lungs as hepatoblastoma metastatectomies. Prediction of postoperative pulmonary function based on perfusion scan merged with CT image and the measurement by CT volumetry, showed that left lingular segmentectomy plus left lower lobectomy could preserve 78% of the preoperative functional values and resection was done. Three weeks after the operation, her condition recovered to the preoperative level. Pathological examination showed that the metastasis was tumor embolism of hepatoblastoma which extended into the pulmonary arterial wall, which to our knowledge, has not been previously reported.

View full abstract

Purpose: To retrospectively evaluate endovascular aortic repair after hybrid open arch repair using the frozen elephant trunk technique for extended thoracic aneurysm.
Methods: Thoracic endovascular aortic repair was performed in 10 of 227 patients (4.4%) who had previously undergone treatment by use of the frozen elephant trunk technique. Six patients had extended thoracic aorta, and 4, complicated aortic dissection. Surgery was scheduled at an early stage in 5 patients; the remaining 5 underwent repair for a new lesion that had developed during the chronic period. The interval between 2 stages was 0 to 86 months (mean, 24 months). The distal landing zone was at the level of thoracic vertebra 10 level in 2 patients; 11, in 4; 12, in 2; and lumbar vertebra 1, in 2. All patients underwent preoperative cerebrospinal fluid drainage.
Results: None of the patients died, nor did any have spinal cord injuries. An Endoleak of the stent graft with shrinkage of aneurysm was not observed. The mean follow-up period was 18 months (range, 5–53 months). No deaths or aortic events occurred after the second-stage operation.
Conclusions: The frozen elephant trunk technique reduced the incidence of second-stage thoracic endovascular aortic repair for extended thoracic aorta and also made the procedure easy and safe.

View full abstract