Hypothermic circulatory arrest at 20 ℃ does not deteriorate coagulopathy compared to 28 ℃ in a pig model.

It is believed that a lower temperature setting of hypothermic circulatory arrest (HCA) in thoracic aortic surgery causes coagulopathy, resulting in excessive bleeding. However, experimental studies that eliminate clinical factors are lacking. The objective of this study is to investigate the influence of the temperature setting of HCA on coagulation in a pig model. Ten pigs were divided into the following two groups: moderate temperature at 28 °C (group M, n = 5) or lower temperature at 20 °C (group L, n = 5). Two hours of HCA during a total of 4 h of cardiopulmonary bypass (CPB) were performed. Blood samples were obtained at the beginning (T1) and the end (T2) of the surgery, and coagulation capability was analyzed through standard laboratory tests (SLTs) and rotational thromboelastometry (ROTEM). In SLTs, hemoglobin, fibrinogen, platelet count, prothrombin time, and activated partial thromboplastin time were analyzed. In ROTEM analyses, clotting time and clot formation time of EXTEM, maximum clot firmness (MCF), and maximum clot elasticity (MCE) of EXTEM and FIBTEM were analyzed. Fibrinogen decreased significantly in both groups (group M, p = 0.008; group L, p = 0.0175) at T2, and FIBTEM MCF and MCE also decreased at T2. There were no differences regarding changes in parameters of SLTs and ROTEM between groups. CPB decreases coagulation capacity, contributed by fibrinogen. However, a lower temperature setting of HCA at 20 °C for 2 h did not significantly affect coagulopathy compared to that of HCA at 28 °C after re-warming to 37 °C.

Hypothermic circulatory arrest does not induce coagulopathy in vitro.

Hypothermic circulatory arrest (HCA) is an essential procedure during aortic surgery to protect organs; however, hypothermia is believed to cause coagulopathy, which is a major fatal complication. This study aimed to clarify the impact of hypothermia on coagulation by eliminating clinical biases in vitro. In the hypothermic storage study, blood samples from five healthy volunteers were stored at 37 â„ƒ (group N) for 3 h or at 20 â„ƒ for 2 h, followed by 1 h of rewarming at 37 â„ƒ (group H). Thromboelastography was performed before and after 3 h of storage. In the mock circulation loop (MCL) study, blood samples were placed in the MCL and (a) maintained at 37 â„ƒ for 4 h (group N, n = 5), or (b) cooled to 20 â„ƒ to simulate HCA with a 0.1 L/min flow rate for 3 h and then rewarmed to 37 â„ƒ (group H, n = 5). The total MCL duration was 4 h, and the flow rate was maintained at 1 L/min, except during HCA. Blood samples collected 15 min after the beginning and end of MCL were subjected to standard laboratory tests and rotational thromboelastometry analyses. Hypothermia had no impact on coagulation in both the hypothermic storage and MCL studies. MCL significantly decreased the platelet counts and clot elasticity in the INTEM and EXTEM assays; however, there was no effect on fibrinogen contribution measured by FIBTEM. Hypothermia does not cause irreversible coagulopathy in vitro; however, MCL decreases coagulation due to the deterioration of platelets.

Proximalized Total Arch Replacement Can Be Safely Performed by Trainee.

BACKGROUND: The aim of the present study was to validate safety of total arch replacement (TAR) using a novel frozen elephant trunk device, operated by trainees as surgical education. METHODS: Sixty-four patients including 19 patients (29.6%) with acute aortic dissection type A (AADA) underwent TAR in our institute between April 2014 and March 2019 were retrospectively analyzed. Twenty-nine patients were operated by trainees (group T) and 35 patients were operated by attending surgeons (group A). RESULTS: Patient characteristics did not differ between groups. Operative time (409.4 ± 87.8 vs. 468.6 ± 129.6 minutes, p = 0.034), cardiopulmonary bypass time (177.7 ± 50.4 vs. 222.9 ± 596.7 minutes, p = 0.019), and hypothermic circulatory arrest time (39.5 ± 13.4 vs. 54.5 ± 18.5 minutes, p = 0.001) were significantly shorter in group A than in group T, but aortic clamping time did not differ between groups (115.3 ± 55.7 vs. 114.2 ± 35.0 minutes, p = 0.924) because the rate of concomitant surgery was higher in group A (37.1 vs. 10.3%, p = 0.014). Thirty-day mortality was 3.1% in the entire cohort. Although operation time was longer in group T, there were no significant difference in postoperative results between the groups, and the experience levels of the main operator were not independent predictors for in-hospital mortality + major postoperative complications. There was no difference in late death and aortic events between groups. CONCLUSIONS: The present study demonstrated that TAR can be safely performed by trainees, and suggests TAR as a possible and safe educational operation.

Serum Neuron-Specific Enolase Level as Predictor of Neurologic Outcome after Aortic Surgery.

BACKGROUND: This study aimed to evaluate the significance of serum neuron-specific enolase (NSE) level as a predictor of neurologic injury in thoracic aortic surgery. METHODS: We neurologically assessed 60 consecutive patients who underwent thoracic aortic surgery for thoracic aortic aneurysm (n = 26) and aortic dissection (n = 34). Using moderate hypothermic circulatory arrest with antegrade cerebral perfusion, total arch replacement and hemiarch replacement were performed in 37 and 23 patients, respectively. Serum NSE levels in venous blood samples drawn before surgery and at 1 day after surgery were measured. Severity of neurologic injury was categorized as either uncomplicated (n = 48), temporary neurologic dysfunction (TND, n = 5), or permanent neurologic dysfunction (PND, n = 7). The extent of stroke was estimated on computed tomography or magnetic resonance imaging. RESULTS: The NSE level significantly differed among the three groups (PND > TND > uncomplicated) on the first postoperative day. Receiver-operating characteristic curve analysis showed that the cutoff value of NSE level was 34.14 ng/mL for neurologic injury (sensitivity, 0.769; specificity, 0.851) and 43.56 ng/mL for PND (sensitivity, 1.000; specificity, 0.963). The NSE level significantly correlated with the extent of stroke (r = 0.61, p < 0.001). CONCLUSION: Serum NSE level is a significant predictor of adverse neurologic outcomes and extent of stroke after thoracic aortic surgery.

Examination of Anterior Leaflet Pseudoprolapse Causing Severe Mitral Regurgitation and Its Ideal Surgical Procedure.

BACKGROUND: The aim of this study is to evaluate severe mitral regurgitation caused by so called atrial leaflet "pseudoprolapse" and verify the effect of simple annular stabilization. METHODS: One-hundred-twenty-two patients underwent surgery for severe mitral regurgitation at our institute between January 2015 to July 2018. Of those, 32 cases diagnosed as anterior leaflet prolapse that underwent mitral repair were analyzed. Ten cases with pseudoprolapse, which is defined as anterior leaflet prolapse without dropping into the left atrium beyond the annular line causing eccentric regurgitation flow directed to the posterior atrium, were classified as the Pseudoprolapse Group. The other 22 cases had obvious anterior leaflet prolapse dropping into the left atrium; these cases were classified as the True Prolapse Group. We compared clinical findings between the 2 groups and reviewed pseudoprolapse cases. RESULTS: Patients in the Pseudoprolapse Group had lower ejection fraction and lower regurgitation volume than those in the True Prolapse Group. A2 lesion as main inflow of regurgitation was more included in the Pseudoprolapse Group. All but one patient in the Pseudoprolapse Group received only simple annuloplasty, and all patients in the True Prolapse Group received leaflet repair and annuloplasty. In both groups, mid-term regurgitation grade and the reoperation rate were satisfactory. In the Pseudoprolapse Group, 6 cases were clarified as atrial functional mitral regurgitation, and 4 cases were considered to have focal posterior leaflet tethering. CONCLUSIONS: Pseudoprolapse cases could be characterized by low ejection fraction, low regurgitation volume, and A2 prolapse. For most cases with pseudoprolapse, simple annuloplasty may be enough, however further study is needed.

[Tricuspid Valve Aneurysm Preoperatively Diagnosed with Right Atrial Tumor;Report of a Case].

A 79-year-old woman visited a hospital with coronary vasospastic angina and supraventricular tachycardia. Periodic inspection of echocardiography suggested a right atrial tumor which was not pointed out 6 months ago, but magnetic resonance imaging suggested a valve aneurysm. These findings were contradictory. We preoperatively diagnosed a cardiac tumor because of its new onset and mobility. Tumor resection and valve repair was planned in consideration of the risk of embolism. As a result, we finally diagnosed tricuspid valve aneurysm from the intraoperative findings and histopathological findings. We assumed that valve aneurysm was formed in the healing process of subclinical infective endocarditis. It was inferred that preoperative diagnosis of valve aneurysm is very difficult.

Combining aortic arch dissection stent implantation and root surgery for aortic dissection type A.

BACKGROUND: Acute aortic dissection type A (AADA) is associated with high perioperative morbidity and mortality. A novel non-covered hybrid prosthesis (AMDS, CryoLife, Kennesaw, USA) can be easily implanted to stabilize the true lumen. However, the role of AMDS for patients requiring additional aortic root surgery has not been described. METHODS: Between 2010 and 2020 a total of n = 370 patients underwent surgery for AADA in our department. Of those, n = 120 underwent treatment for aortic root in addition to proximal arch replacement without resection of the aorta beyond the innominate artery (Control, n = 111) and were compared to patients who received additional AMDS implantation (AMDS, n = 9). RESULTS: Aortic valve repair was performed in 48.6% (Control) and in 55.6% of AMDS patients. Cardiopulmonary bypass (Control: 248 ± 76 min, AMDS: 313 ± 53 min, P < 0.01) time as well as circulatory arrest time of the lower body (Control: 30 ± 15 min, AMDS: 52 ± 12 min, P < 0.01) was prolonged in the AMDS group. Nevertheless, postoperative in-hospital morbidity such as dialysis (Control: 22.4%, AMDS: 11.1%, P = 0.68) and stroke (Control: 17.0%, AMDS: 22.2%, P = 0.65) were comparable. In-hospital death (Control: 21.8%, AMDS: 11.1%, P = 0.68) and the compound end-point MACCE (Control: 38.7%, AMDS: 44.4%, P = 0.74) did also not differ. CONCLUSIONS: Addressing the arch by implantation of AMDS prolongs cardiopulmonary bypass and circulatory arrest time, however without relevant impairments of short-term outcome. Combining root surgery with replacement of the proximal aortic arch and AMDS implantation seems feasible and safe as it did not impair the early postoperative outcome.

Recombinant Activated Factor VII in Aortic Surgery for Patients Under Hypothermic Circulatory Arrest.

Purpose: We aimed to identify the risk factors of critical bleeding and investigate the safety of recombinant activated factor VII (rFVIIa) in aortic surgery under hypothermic circulatory arrest (HCA). Patients and Methods: The present single-center retrospective study compared the baseline characteristics of 144 patients who underwent aortic surgery under HCA at our institute. Among the total cohort of 144 patients, 42 received rFVIIa (rFVIIa group), while the remaining 102 patients did not (non-rFVIIa group). Perioperative bleeding and transfusions, postoperative 30-day mortality, and adverse events (AEs) were analyzed in 29 propensity score-matched pairs. Results: Before surgery, the rFVIIa group demonstrated a greater number of shocks (p=0.019), higher JapanSCORE II mortality rate (p=0.033), low platelet count (p=0.015) and fibrinogen (p<0.001) level, prolonged activated partial thromboplastin time (aPTT) (p=0.005) and prothrombin time international normalized ratio (PT-INR) (p=0.006), and longer aortic cross clamp time (p=0.049). Postoperative bleeding, transfusion, 30-day mortality, and AEs were comparable between the groups both in the entire-unmatched cohort and propensity score matching cohort. Conclusion: Preoperative shock, higher JapanSCORE II mortality rates, low platelet and fibrinogen levels, prolonged aPTT and PT-INR, and longer aortic clamping time might be risk factors for excessive bleeding and indicate the need for rFVIIa treatment. The present study suggests that rFVIIa can be safely used to address critical and continuous bleeding in spite of adequate transfusion and supplementation of other coagulation factors in aortic surgery under HCA, without an increase in 30-day mortality and AEs.

The Impact of Chronic Limb-Threatening Ischemia on Cardiac Surgery.

Purpose: The effect of chronic limb threatening ischemia (CLTI) on advanced cardiac disease, which requires surgical treatment, has rarely been reported. The purpose of this study was to review the outcomes of cardiac surgery in patients with CLTI and determine the risk factors, with a particular focus on the severity of CLTI. Patients: The baseline characteristics and outcomes of 33 patients who were treated for CLTI and underwent cardiac surgery were retrospectively analyzed. The states of CLTI were evaluated based on the Wound, Ischemia, and foot Infection (WIfI) classification system, and 33 patients were divided into the low-WIfI group (stages 1-2, n = 13) and high-WIfI group (stages 3-4, n = 20). Results: The in-hospital mortality rate was 0% in low-WIfI group and 35% in high-WIfI group (p = 0.027). Postoperative complications, particularly severe infections, occurred more frequently among high-WIfI group than low-WIfI group (70.0% vs. 23.1%, p < 0.01). Multivariable analysis identified foot infection grade as a WIfI classification factor and lower albumin levels as factors significantly associated with postoperative complications. The 1-year and 2-year survival rates were 84.6% and 67.7% in low-WIfI group and 45% and 28.1% in high-WIfI group, respectively (p = 0.011). Conclusions: Cardiac surgery in patients with high WIfI stage was an extremely high-risk procedure. In such patients, lowering the WIfI stage by lower extremity revascularization and/or debridement of diseased parts prior to cardiac surgery can be considered.

Transplantation after Mustard operation for transposition of the great arteries.

As long-term outcomes of congenital heart diseases improve, the probability of adult patients presenting for heart transplantation for late failure of congenitally corrected heart disease also increases. In patients with dextro-transposition of the great arteries (d-TGA) who were initially treated in the era of Mustard or Senning procedures and before Jatene procedure was introduced, progressive systemic right ventricular failure represents a problem in the very long-term follow-up. We report a rare case of heart transplantation as a third operation 36 years after Mustard procedure in a patient with d-TGA experiencing late failure of the systemic right ventricle.

A Clampless Aortoprosthetic End to Side Anastomotic Device with Large Diameter Aortic Puncher.

INTRODUCTION: To facilitate safe anastomosis of a vascular prosthesis onto the proximal ascending aorta without side clamping, a clampless anastomotic device with large diameter aortic puncher was developed. REPORT: First, a vascular prosthesis is anastomosed onto the aorta without making a hole, then the aortic wall within the prosthesis is punched out using the device. DISCUSSION: After further refinement of the present device, endovascular surgery with debranching could be performed more safely and quickly.

Routine postoperative computed tomography is superior to cardiac ultrasonography for predicting delayed cardiac tamponade.

Delayed cardiac tamponade (DCT) can be a fatal complication after cardiac surgery, but its early diagnosis and/or prediction is sometimes difficult. This study aimed to confirm the efficacy of postoperative computed tomography (CT) as routine examination compared with transthoracic echocardiography (TTE) for predicting DCT after cardiac surgery. This study was a retrospective single-center analysis of 485 consecutive patients undergoing cardiac surgery from January 2016 to July 2018 in our department. Among them, 237 patients were enrolled in this analysis after application of the exclusion criteria: minimally invasive surgery via small thoracotomy, death in the acute phase, and no CT 7 ± 3 days after surgery. Pericardial effusion (PE) was measured at the thickest part using CT and TTE. DCT was found in nine enrolled patients (3.8%). The mean PE on CT was 7.7 ± 5.5 mm in the no event group and 23.4 ± 5.7 mm in the DCT group (p = 0.026), whereas the mean PE on TTE was 6.2 ± 4.5 mm in the no event group and 10.8 ± 4.4 mm in the DCT group (p = 0.170). On multivariate analysis, PE greater than 20 mm on CT (Odds ratio, 13.93; 95% confidence interval 2.57-75.46; p = 0.002) was a significant predictor of DCT. The present study suggested that postoperative CT examination is superior to TTE for predicting DCT. If PE is less than 20 mm on CT, it could be treated conservatively; otherwise, preventive/therapeutic intervention should be considered.

Hypothermic circulatory arrest induced coagulopathy: rotational thromboelastometry analysis.

OBJECTIVES: Hypothermic circulatory arrest (HCA) has been considered to cause coagulopathy during cardiac surgery. However, coagulopathy associated with HCA has not been understood clearly in details. The objective of this study is to analyze the details of coagulopathy related to HCA in cardiac surgery by using rotational thromboelastometry (ROTEM). METHODS: We retrospectively analyzed 38 patients who underwent elective cardiac surgery (HCA group = 12, non-HCA group = 26) in our hospital. Blood samples were collected before and after cardiopulmonary bypass (CPB). Standard laboratory tests (SLTs) and ROTEM were performed. We performed four ROTEM assays (EXTEM, INTEM, HEPTEM and FIBTEM) and analyzed the following ROTEM parameters: clotting time (CT), clot formation time (CFT), maximum clot firmness (MCF) and maximum clot elasticity (MCE). The amount of perioperative bleeding, intraoperative transfusion and perioperative data were compared between the HCA and non-HCA group. RESULTS: Operation time and hemostatic time were significantly longer in the HCA group, whereas CPB time had no difference between the groups. The amount of perioperative bleeding and intraoperative transfusion were much higher in the HCA group. SLTs showed no difference between the groups both after anesthesia induction and after protamine reversal. In ROTEM analysis, MCE contributed by platelet was reduced in the HCA group, whereas MCE contributed by fibrinogen had no difference. CONCLUSION: Our study confirmed that the amount of perioperative bleeding and intraoperative transfusion were significantly higher in the HCA group. ROTEM analysis would indicate that clot firmness contributed by platelet component is reduced by HCA in cardiac surgery.

Correction to: Hypothermic circulatory arrest induced coagulopathy: rotational thromboelastometry analysis.

The article "Hypothermic circulatory arrest induced coagulopathy: rotational thromboelastometry analysis", written by Hayato Ise, Hiroto Kitahara, Kyohei Oyama, Keiya Takahashi, Hirotsugu Kanda, Satoshi Fujii, Takayuki Kunisawa, Hiroyuki Kamiya, was originally published electronically on the publisher's internet portal on 7 June 2020 without open access.

Pulmonary artery banding for initial treatment of ventricular septal rupture.

Ventricular septal rupture (VSR) is a serious and fatal mechanical complication after acute myocardial infarction. Emergent or urgent, surgical/transcatheter intervention is necessary to treat VSR, though the outcome is not favorable. We performed temporary pulmonary artery banding (PAB) in an 85-year-old man who presented with chest pain to adjust the shunt flow through the VSR, which prevented further pulmonary edema and delayed the timing of surgical repair. There has been no report showing successful PAB performed for VSR after myocardial infarction.

Manual repositioning of lung hernia after minimally invasive cardiac surgery.

Minimally invasive cardiac surgery has recently become widespread because it has few disadvantages. However, lung hernia has been reported as a rare complication of minimally invasive cardiac surgery (MICS), and normally requiring additional surgical procedures. We describe herein a case of manual repositioning of lung hernia after MICS.

Open brachiocephalic artery stent for static obstruction caused by acute type A aortic dissection.

Brachiocephalic artery dissection complicated by acute type A aortic dissection occasionally causes cerebral malperfusion. Although immediate central aortic repair has been the standard treatment for aortic dissection, dissection in supra-aortic vessels frequently remains after the surgery. The residual brachiocephalic artery dissection is reported to be associated with late neurological events. Therefore, additional intervention for brachiocephalic artery dissection during central aortic repair should be considered in selected cases. In this report, we describe two cases requiring open brachiocephalic artery stenting simultaneous with central aortic repair. There were no neurological or stent induced complications at latest follow-up.

Cerebral Circulation During Retrograde Cerebral Perfusion: Evaluation Using Laser Speckle Flowgraphy.

BACKGROUND: The cerebroprotective effect of retrograde cerebral perfusion (RCP) and selective antegrade cerebral perfusion (SCP) still remains controversial. Laser speckle flowgraphy has shown much promise for novel perioperative neuromonitoring by assessing blood flow of the optic nerve head. This study aimed to evaluate the cerebral microcirculation in humans using laser speckle flowgraphy during simple circulatory arrest, RCP, and SCP under moderate hypothermia and to investigate whether RCP under moderate hypothermia is a reliable method of cerebral protection. METHODS: A total of 23 consecutive patients who underwent a scheduled aortic arch or hemiarch surgical procedure on thoracic aorta aneurysm were enrolled. The laser speckle flowgraphy measurement that calculates mean blur ratio, a parameter of cerebral circulation, was obtained 6 times: after induction of anesthesia, baseline (T1), after initiation of cardiopulmonary bypass with cardiac arrest (T2), simple circulatory arrest (T3), RCP (T4), SCP (T5), and after the termination of cardiopulmonary bypass (T6). RESULTS: Both mean blur ratios of simple circulatory arrest and RCP were significantly decreased compared with baseline. In contrast, no significant differences were observed between simple circulatory arrest and RCP. The mean blur ratio of SCP was significantly increased compared with both simple circulatory arrest and RCP. CONCLUSIONS: In conclusion, no significant difference was observed in the cerebral circulation between RCP and simple circulatory arrest without adjunctive strategy under moderate hypothermia. In contrast, the cerebral circulation during SCP was significantly higher than simple circulatory arrest and RCP. These results suggest that cerebral microcirculation may not be adequate during RCP compared with SCP under moderate hypothermia.

Dramatic improvement of left ventricular function after switching the ventricular pacing site from the right ventricular apex to the left ventricular free wall via a left mini thoracotomy: a case report.

The case of a patient with pacemaker-induced cardiomyopathy in whom left ventricular (LV) function was dramatically improved after switching the ventricular pacing site from the right ventricular apex to the LV free wall via a left mini thoracotomy due to pacemaker-associated infective endocarditis (PAIE) is presented. Our experience suggests that a surgically implanted epicardial LV lead on the LV lateral wall can be a good alternative pacing site that preserves LV function, especially in patients with PAIE.

Failed transcatheter pulmonary artery embolization in a patient suffering from massive hemoptysis after thoracic endovascular aortic repair.

An emergency thoracic endovascular aortic repair (TEVAR) with zone 2 landing without revascularization of the left subclavian artery was performed due to the impending rupture of a distal arch aneurysm in an old patient presenting hemoptysis. Two months later, the patient had recurrent massive hemoptyses and continued after additional zone 0 TEVAR. The lung parenchyma was considered to be the bleeding source and transcatheter pulmonary artery embolization was performed, and the episodes of massive hemoptysis appeared to have ceased. However, the patient died of sudden recurrent massive hemoptysis 40 days later. Inflammation and/or infection of the lung parenchyma adjunct to the aortic aneurysm could be cause of fatal hemoptysis, and aggressive therapy such as lung resection should be considered in such patients.