Outcomes of 881 Consecutive Coronary Artery Bypass Graft Patients Using Heartstring Device.

BACKGROUNDS: One of the strategies to prevent stroke after coronary artery bypass grafting (CABG) may be the use of a device for proximal anastomosis without partial clamp of the ascending aorta. METHODS: We retrospectively investigated early and late outcomes in consecutive 881 patients undergoing isolated CABG using Heartstring for proximal anastomosis from January 2008 to December 2022, to reveal the validity to use it. All patients underwent preoperative imaging workups to evaluate neurovascular atherosclerosis. RESULTS: The mean age of the patients was 68.9 years, 20% were female and 13% had previous history of stroke. CABG was on-pump beating heart (52.2%) or off-pump (47.8%) with a mean number of distal anastomoses of 3.38 ± 0.93, using 1.62 ± 0.53 Heartstring devices under different aortic manipulations. In-hospital mortality was 2.0% and perioperative stroke rate was 0.9%, none of them died during hospital stay. During the follow-up period of 70 ± 47 months, the overall actuarial survival rates were 86 and 66%, and major adverse cardiac and cerebrovascular events (MACCEs)-free rates were 86 and 70% at 5 and 10 years, respectively. On multivariable analysis, risk factors for late death included male, previous history of stroke, postoperative sternomediastinitis, late new-onset stroke, and MACCEs, but did not include the perioperative stroke. CONCLUSION: Low stroke rate, as low as 0.9%, after CABG using Heartstring for proximal anastomosis, although under a variety of aortic manipulations, may contribute to the improved long-term prognosis.

Optimal timing of SARS-CoV-2 vaccination prior to cardiovascular surgery under cardiopulmonary bypass.

BACKGROUND: mRNA vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) became common. We investigated the optimal timing for inoculation against SARS-COV-2 in the candidates for cardiac surgery under cardiopulmonary bypass (CPB). METHODS: In 100 patients with preoperative vaccination, who underwent CPB surgery between July 2021 and February 2022, the IgG against the receptor binding domain (RBD-IgG), with a threshold of >100 binding antibody unit (BAU)/mL for adequate immunity, was measured. RESULTS: The vaccines, including 87 BNT162b2 (Pfizer/BioNTech) and 13 mRNA-1273 (Moderna), were inoculated at 98.8 ± 59.4 days before surgery. The median RBD-IgG titers before surgery, 1 day after surgery, and 1 month after surgery were 166.8, 100.0, and 84.0 BAU/mL, respectively. The standby interval (SBI) from the vaccination to the surgery showed a significantly negative correlations with the RBD-IgG titer before the surgery (p < 0.001). A cut-off SBI for RBD-IgG >100 BAU/mL before surgery was <81 days with a sensitivity of 76%, specificity of 62%, and area under ROC value of 0.73 (p = 0.03). The patients with SBI <81 days (n = 48) had significantly higher RBD-IgG (>100 BAU/mL) than those with SBI ⩾81 days (n = 52) at all perioperative periods. CONCLUSIONS: Although 40% of the RBD-IgG titers reduce 1 day after CPB surgery, the patients who received the SARS-COV-2 vaccination within an 81-day window prior to the surgery maintained a desirable RBD-IgG level, even up to 1 month after surgery. It may be important to schedule the surgery no later than 81 days after the vaccination.

Contributing factors to heparin resistance during cardiopulmonary bypass.

Since the risk factors for heparin resistance (HR) before cardiopulmonary bypass (CPB) have not been fully clarified, this study investigated the contributing factors for HR after the initial unfractionated heparin (UFH) dose of 500 IU/kg. We retrospectively analyzed the data of 371 patients who underwent CPB surgery, with the initial UFH dose of 500 IU/kg, between May 2017 and December 2021. We defined HR as the failure to achieve activated clotting time (ACT) of > 480 s after the initial UFH dose of 500 IU/kg. HR was observed in 36 patients (9.7%) (HR group), while HR was not observed in 335 patients (control group). The HR group included significantly more patients with preoperative use of UFH, with significantly higher white blood cell counts, fibrinogen, fibrinogen degradation products, D-dimer, and C-reactive protein, and lower hemoglobin and albumin. The multivariable logistic regression analysis identified albumin (OR: 3.09, 95% CI 1.3504-7.0845, p = 0.0075) and fibrinogen (OR: 0.99, 95% CI 0.9869-0.9963, p = 0.0003) as independent predictors for HR. Using the Youden index, the cutoffs of albumin and fibrinogen were calculated as 3.8 g/dL and 303 mg/dL, respectively. The receiver operating characteristic curves showed the predictive performance of albumin (area under the curve (AUC): 0.78, sensitivity: 65%, specificity: 81%) and fibrinogen (AUC: 0.77, sensitivity: 56%, specificity: 88%). The incidence of HR after the initial UFH dose of 500 IU/kg was 9.7%. The preoperative albumin < 3.8 g/dL and fibrinogen > 303 mg/dL were independent predictors for HR.

Comparison between Off-Pump and On-Pump Beating Heart Coronary Artery Bypass Grafting.

BACKGROUND: Although coronary artery bypass grafting (CABG) is performed via three different techniques, conventional, on-pump beating heart CABG (ONBHCAB), or off-pump CABG (OPCAB), data are limited to compare ONBHCAB with OPCAB. METHODS: We retrospectively investigated the postoperative cardiac biomarkers, creatine kinase-MB (CK-MB), and troponin I (cTnI), and early and late outcomes in 806 patients undergoing isolated ONBHCAB or OPCAB between February 2008 and September 2022. To eliminate the bias between different groups, propensity score matching was conducted to validate the findings. RESULTS: After matching, the number of each study group totaled 270 patients. In both complete and matched cohorts, early outcomes, including morbidities and mortalities, were similar. However, cTnI and CK-MB levels were significantly higher after ONBHCAB than after OPCAB with median peak cTnI of 9.85 versus 4.60 ng/mL and median peak CK-MB of 48.45 versus 17.10 ng/mL in the matched cohort, which were quite low, below the threshold for values defining perioperative myocardial infarction. At follow-up of 73 ± 45 months, the overall actuarial survival rates were similar between the ONBHCAB and OPCAB patients (86 vs. 87% at 5 years and 64 vs. 68% at 10 years, respectively, in the matched cohort). CONCLUSION: ONBHCAB may be a comparable alternative to OPCAB with similar early and late outcomes, despite higher elevation of postoperative cardiac biomarkers. ONBHCAB provides more efficient hemodynamic support, providing a better surgical visual field, than OPCAB while reducing the risk of incomplete revascularization.

Fecal Occult Blood Screening before Cardiac Surgery.

BACKGROUND: Concerns of gastrointestinal (GI) bleeding after cardiac surgery are increasing with increased use of antiplatelets and anticoagulants. We investigated the roles of preoperative screening for fecal occult blood by fecal immunochemical test (FIT) widely used to detect GI bleeding and cancer. METHODS: A retrospective review was done in 1,663 consecutive patients undergoing FIT before cardiac surgery between years 2012 and 2020. One or two rounds of FIT were performed 2 to 3 weeks before surgery, when antiplatelets and anticoagulants were not suspended yet. RESULTS: Positive FIT (> 30 µg of hemoglobin/g of feces) was observed in 227 patients (13.7%). Preoperative risk factors for positive FIT included age > 70 years, anticoagulants, and chronic kidney disease. Of those with positive FIT, 180 patients (79%) received preoperative endoscopy, including gastroscopy (n = 139), colonoscopy (n = 9), and both (n = 32), with no findings of bleeding. The most common finding of gastroscopy was atrophic gastritis (36%) while early gastric cancer was detected in 2 patients. The most common finding of colonoscopy was colon polyps (42%) while colorectal cancer was detected in 5 patients. Of 180 FIT-positive patients receiving endoscopy, 8 (4.4%) underwent preoperative GI treatment, while postoperative GI events were documented in 28 (15.6%). Of 1,436 with negative FIT, 21 (1.5%) presented GI complications after surgery. CONCLUSION: Preoperative FIT, which is influenced by anticoagulant use, has little impacts on identification of GI bleeding sites. However, it may be useful to detect GI malignant lesions, potentially impacting operative risks, surgical strategies, and postoperative management.

Flow characteristics of in-situ internal thoracic artery graft with competitive flow.

We report flow characteristics of an in-situ internal thoracic artery (LITA) graft with angiographically competitive flow to the left anterior descending artery (LAD), based upon intraoperative transit-time flow measurement (TTFM) during coronary artery bypass grafting with aortic valve replacement (AVR) and during re-AVR seven years later. Although intraoperative TTFM of the graft showed lower mean flow and higher pulsatility index, suggesting inadequate anastomosis, fast Fourier transform (FFT) analysis of TTFM waveforms presented gradual waning of the amplitude, as shown in patent grafts. FFT analysis of the TTFM waveforms is helpful to judge the patency of LITA to LAD, even with competitive flow. Learning objective: The internal thoracic artery (LITA) graft to left anterior descending artery (LAD) with angiographically competitive flow shows gradual waning of the amplitude on fast Fourier transform (FFT) analysis of the transit-time flow measurement (TTFM) waveforms, although lower mean graft flow, higher pulsatility index, and higher systolic reversal flow may suggest inadequate anastomosis. FFT analysis of the TTFM waveforms is useful to judge the patency of LITA to LAD, even with competitive flow.

Effects of Fractional Flow Reserve on Coronary Artery Bypass Graft Flow to Left Anterior Descending Artery.

BACKGROUND: The relationships between preoperative fractional flow reserve (FFR) values of the left anterior descending artery (LAD), FFRLAD, and intraoperative transit time flow measurement (TTFM) variables in coronary artery bypass grafting (CABG) remain unclear.Methods and Results: We retrospectively collected data for 74 in situ left internal thoracic artery (LITA) grafts and 27 saphenous vein grafts (SVGs) to the LAD that were shown to be patent on postoperative angiography. Spearman correlation coefficients were determined between FFRLADand TTFM parameters of the LITA graft, as follows: maximum flow (Qmax), -0.22 (P=0.077); minimum flow (Qmin), -0.40 (P=0.014); mean flow (Qm), -0.35 (P=0.039); pulsatility index (PI), 0.33 (P=0.008); diastolic filling (DF): 0.01 (P=0.83); and systolic reverse flow (SRF), 0.37 (P=0.002). Spearman correlation coefficients between FFRLADand TTFM parameters of the SVG to LAD were: Qmax, -0.65 (P=0.004); Qmin, -0.43 (P=0.044); Qm, -0.75 (P=0.001); PI, 0.53 (P=0.033); DF, 0.14 (P=0.48); and SRF, 0.61 (P=0.009). CONCLUSIONS: Both LITA grafts and SVGs to the LAD show negative correlations for FFRLADwith Qminand Qm, but positive correlations for FFRLADwith PI and SFR. These relationships between FFRLADand TTFM variables of CABG grafts to the LAD should be recognized.

Surgical repair of mitral valve regurgitation with anomalous unilateral single pulmonary vein.

We report a case of surgically repaired symptomatic mitral valve regurgitation (MR) in a 61-year-old woman with anomalous unilateral single pulmonary vein. A two-staged surgery was scheduled; first a catheter embolization of anomalous vessel to avoid recirculation of the blood into the left atrium during cardiopulmonary bypass, and second a mitral valve repair via right lateral thoracotomy. Learning objective: Scimitar sign is a horn-like shape on plain chest radiograph. One of the possible diagnoses is partial anomalous pulmonary venous return (APVR), which often requires surgical interventions due to comorbidities of congenital heart disease and recurrent pneumonia [1-3]. Another is anomalous unilateral single pulmonary vein (AUSPV), which is generally asymptomatic, and therefore, requires no medical interventions. This case addresses the advantage of multidetector computed tomography (CT) and the safety of two-staged strategy.

Mortality trends of aortic stenosis in high-income countries from 2000 to 2020.

OBJECTIVE: The purpose of this study is to describe recent mortality trends from aortic stenosis (AS) among eight high-income countries. METHODS: We analysed the WHO mortality database to determine trends in mortality from AS in the UK, Germany, France, Italy, Japan, Australia, the USA and Canada from 2000 to 2020. Crude and age-standardised mortality rates per 100 000 persons were calculated. We calculated age-specific mortality rates in three groups (<64, 65-79 and ≥80 years). Annual percentage change was analysed using joinpoint regression. RESULTS: During the observation period, the crude mortality rates per 100 000 persons increased in all the eight countries (from 3.47 to 5.87 in the UK, from 2.98 to 8.93 in Germany, from 3.84 to 5.52 in France, from 1.97 to 4.33 in Italy, from 1.12 to 5.49 in Japan, from 2.14 to 3.38 in Australia, from 3.58 to 4.22 in the USA and from 2.12 to 5.00 in Canada). In joinpoint regression of age-standardised mortality rates, trend changes towards a decrease were observed in Germany after 2012 (-1.2%, p=0.015), Australia after 2011 (-1.9%, p=0.005) and the USA after 2014 (-3.1%, p<0.001). Age-specific mortality rates in age group ≥80 years had shifts towards decreasing trends in all the eight countries in contrast to other younger age groups. CONCLUSIONS: While crude mortality rates increased in the eight countries, shifts towards decreasing trends were identified in age-standardised mortality rates in three countries and in the elderly aged ≥80 years in the eight countries. Further multidimensional observation is warranted to clarify the mortality trends.

Cardiac recovery from COVID-19-associated fulminant myocarditis by extracorporeal biventricular assist.

We report a case of cardiac recovery from coronavirus disease 2019 (COVID-19)-associated fulminant myocarditis in a 48-year-old woman diagnosed with COVID-19 infection 4 days before, whose hemodynamic collapse were resuscitated first with venoarterial extracorporeal membranous oxygenation, followed by escalation to extracorporeal biventricular assist devices (ex-BiVAD) using two centrifugal pumps and an oxygenator. She was likely to be multisystem inflammatory syndrome in adults (MIS-A) negative. Cardiac contractility gradually recovered after the 9th day of ex-BiVAD support, and the patient was successfully weaned from ex-BiVAD on the 12th day of support. Due to postresuscitation encephalopathy, she was transferred to the referral hospital for rehabilitation with recovered cardiac function. The histopathology of the myocardial tissue showed smaller amounts of lymphocytes and more infiltration of macrophages. It is important to recognize two phenotypes of MIS-A+ or MIS-A-, with distinct manifestations and outcomes. It is also important to refer urgently such patients with COVID-19-associated fulminant myocarditis, showing different histopathology from usual viral myocarditis, with evolution toward refractory cardiogenic shock to a center with capability for advanced mechanical support to avoid a too-late cannulation. Learning objective: We should recognize the clinical course and histopathology of the multisystem inflammatory syndrome in adults phenotype of coronavirus disease 2019-associated fulminant myocarditis. We should urgently refer such patients with evolution toward refractory cardiogenic shock to a center with capability for advanced mechanical support, such as venoarterial extracorporeal membrane oxygenation, Impella (Abiomed, Danvers, MA, USA), and extracorporeal biventricular assist devices.

Mid-term results of distal anastomosis to the true lumen for chronic type B aortic dissection.

We investigated whether distal anastomosis to the true lumen in open surgical repair of descending aorta for chronic type B aortic dissection improved the long-term outcomes with aortic remodeling. We retrospectively reviewed 71 patients with chronic type B aortic dissection, excluding those with connective tissue disorder, from October 2001 to June 2021. The patients who underwent distal true lumen anastomosis (group T, n = 36) were compared to those with both lumens' anastomosis (group B, n = 35), regarding survival, overall and distal aortic events. The growth rates of the distal aorta (maximum diameter in descending thoracic, suprarenal and infrarenal abdominal aorta) were also investigated. Median age was significantly higher in group T (T; 66 vs B; 60, P = .001). Group T had significantly higher rates of complete and partial thrombosis formation in the false lumen than group B postoperatively (26.9 vs 0%, P = .01 for complete, 65.4 vs 3.9%, P < .0001 for partial, respectively). At median follow-up for 6.8 years of 63 patients (88.7%), survival, overall and distal aortic event-free rates, and the growth rates of the distal aorta were not significantly different between the groups. Distal anastomosis to the true lumen did not improve mid-term survival, aortic event-free rates and the growth rates of the distal aorta compared with that of both lumens for chronic type B aortic dissection.

Early Sternal Bone Healing after Thermoreactive Nitinol Flexigrip Sternal Closure.

PURPOSE: Thermoreactive nitinol Flexigrip has been developed to ensure better fixation than conventional wire closure. To verify the advantage of Flexigrip over the conventional wiring, we compared early sternal bone healing on computed tomography (CT). METHODS: A prospective cohort study enrolled the first consecutive 80 patients with wiring and the second consecutive 44 patients undergoing Flexigrip sternal closure. The primary endpoint was sternal healing evaluated quantitatively using a 6-point scale and measured gaps/offsets of the sternal halves at 6 levels on CT scans on the 14th postoperative day. Secondary endpoints included pain scores and sternal complications 1 month after surgery. RESULTS: Compared with the patients of wiring, those who received Flexigrips showed higher 6-point scores at most sternum levels, less frequent gaps (52% vs 70%, p = 0.04), lower offsets (3.3 ± 0.9 mm vs 4.3 ± 0.7 mm, p <0.001) at the manubrium, and less frequent gaps (25% vs 43%, p = 0.04) and offsets (2.3% vs 24%, p = 0.002) at the middle of sternum. The pain scores and sternal complication rates were similar between both groups. CONCLUSION: CT evaluation 2 weeks after surgery revealed that Flexigrip sternal closure showed less gaps and offsets of the sternal halves, suggesting faster sternal bone union when compared to the wiring.

Thrombosed stuck mitral valve during advanced mechanical circulatory support for post-cardiotomy shock.

We report a case of mechanical prosthetic mitral valve thrombosis in a 52-year-old woman with previous diagnosis of dilated cardiomyopathy, who was supported with advanced mechanical circulatory support after urgent mechanical mitral valve replacement (MVR) and tricuspid annuloplasty. Difficult weaning from cardiopulmonary bypass needed support with veno-arterial extracorporeal membranous oxygenation and Impella (Abiomed Inc, Danvers, MA, USA), so-called ECPELLA. Temporary discontinuation of heparin and massive blood transfusion were necessary due to four times of reoperation for bleeding during ECPELLA support. Poor recovery of cardiac function needed escalation from ECPELLA to extracorporeal biventricular assist device (ex-BiVAD) using two centrifugal pumps on Day 12. After gradual decrease in the left ventricular assist device flow, transesophageal echocardiography and fluoroscopic images revealed the stuck leaflets of the mitral prosthesis. Therefore, the patient underwent re-MVR with a bioprosthesis on Day 18, followed by continued assistance with ex-BiVAD. The patient was finally weaned from ex-BiVAD on Day 28 and was transferred to the referral hospital for rehabilitation. She was alive in good general condition at 2-year follow-up. It is important to balance the effects of anticoagulation on advanced mechanical circulatory support with ECPELLA, against the side effects of bleeding, especially in post-cardiotomy patients with bleeding tendency. .

Effects of cardiopulmonary bypass on immunoglobulin G antibody titres after SARS-CoV2 vaccination.

OBJECTIVES: Patients with cardiovascular disease are vulnerable to severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) infection. Although SARS-CoV2 vaccination may be effective, its impact on surgical patients is not well studied. We investigated the effects of cardiovascular surgery, especially under cardiopulmonary bypass (CPB), on the antibody titres after SARS-CoV2 vaccination. METHODS: A prospective observational study was designed for patients undergoing surgery between July and November 2021. The immunoglobulin G against the receptor-binding domain was measured and antibody preserved rate (APR) was calculated from perioperative titres comparison. RESULTS: Enrolled 63 study patients were divided into 39 undergoing surgery with CPB (Group CPB) and 24 without CPB (Group None). Preoperative vaccines were BNT162b2 (Pfizer/BioNTech) (n = 58, 92%) and mRNA-1273 (Moderna) (n = 5, 8%). While immunoglobulin G against the receptor-binding domain titres did not significantly decrease after surgery in Group None, they decreased significantly in Group CPB from 21.80 [11.15, 37.85] to 11.95 [6.80, 18.18] U/ml (P < 0.001) a day after surgery, 11.40 [7.85, 22.65] U/ml (P < 0.001) 14 days after surgery and 7.60 [4.80, 17.60] U/ml (P < 0.001) a month after surgery. The APRs a day after the surgery were significantly lower in Group CPB (0.46 [0.41, 0.60]) than in Group None (0.80 [0.68, 0.87]) (P < 0.001). CONCLUSIONS: The SARS-CoV2 antibody titres significantly decreased with lower APRs immediately after surgery under CPB. Based on our informative results, careful considerations of vaccination schedule might be required for surgery under CPB.

Impact of supra-aortic vessel dissection on the neurological outcome in surgery for acute type A aortic dissection.

We investigated whether supra-aortic vessel (SAV)s dissection is a risk factor for neurological dysfunction (ND) after surgical repair for type A acute aortic dissection (TAAAD). A retrospective review was done in 178 patients with TAAAD undergoing aortic repair between 2015 and 2019, comparing those with SAV dissection to those without it. Preoperatively, 93 patients (54.4%) had SAV dissection. Postoperatively, ND occurred in 26 patients (14.6%), 17 of whom (65.4%) already had been present with preoperative ND. Patients with SAV dissection were more likely to have postoperative ND than those without it (21.5% vs 7.7%; p = 0.02). The severity of preoperative dissection-related stenosis in common carotid artery significantly related to postoperative ND (right; p =0.0071, left; p < 0.0001). Multivariable analysis showed dissection-related stenosis of > 75% in brachiocepharic and left common carotid arteries, and thrombosed false lumen in common carotid arteries were independent risk factors for postoperative ND. However, SAV dissection was not related to new onset of ND. Dissection with stenosis of > 75% in SAVs were significantly decreased after aortic repair and even after ascending aorta/hemiarch replacement. In conclusion, ND after surgical repair for TAAAD is closely related to SAV dissection, especially to stenosis of > 75% and thrombosed false lumen in common carotid arteries. Aortic repair significantly decreased SAV dissection and severity of stenosis.

Hybrid repair for Kommerell's diverticulum and right aortic arch with aberrant right vertebral artery.

Kommerell's diverticulum (KD) is a rare aneurysm of the origin of an aberrant subclavian artery. Hybrid aortic arch repair for KD is being performed more often. We report hybrid arch repair for KD in a 63-year-old man with a right aortic arch and aberrant right vertebral artery, an extremely rare variant. We performed total arch replacement to completely reconstruct the five cervical arteries with elephant trunk to create an adequate landing zone, followed by second-stage endovascular stent-grafting from the ascending aorta to the proximal descending aorta.

Prophylactic use of vacuum-assisted closure system for cannula sites: A case of extracorporeal biventricular assist devices for 295 days.

We report wound management using a vacuum-assisted closure (VAC) system for the cannula sites of extracorporeal biventricular assist devices (BiVADs) for 295 days in a 23-year old Chinese female patient with fulminant giant cell myocarditis, who finally underwent heart transplantation. When the cannula sites appeared necrotic 3 months after BiVADs placement, she received negative pressure wound therapy prophylactically for four cannula sites, using a VAC system for 3 months, followed by no infections. Such prophylactic VAC therapy, using the skin barrier paste usually used for the ostomy pouching system to create a flatter surface and airtightness, may be useful to avoid cannula site infections, which is still a fatal complication causing sepsis, especially in patients with extracorporeal BiVADs.

Two-staged surgical treatment for Kommerell diverticulum with a right aortic arch and an aberrant left subclavian artery.

Kommerell diverticulum (KD) is an aneurysm of the orifice of an aberrant subclavian artery (SCA) from the descending aorta or aortic arch. We have performed two-staged surgical strategy for the treatment of KD with right aortic arch. The first step was the bypass grafting between the left common carotid artery and the aberrant left SCA with occlusion of the distal side of KD with the plug. The second step was the descending aorta replacement through the right thoracotomy. Four patients underwent these operations. No hospital deaths or major complications were observed. All four patients were discharged and have been alive for 1-6 years without any health problems. Two of four patients had symptoms of dysphagia preoperatively, and it resolved postoperatively in both patients. No hoarseness occurred after surgery, and 1-6 years of CT observation showed no recanalization of the vascular plug.