Hemodynamic management during off-pump coronary artery bypass surgery: a narrative review of proper targets for safe execution and troubleshooting / 대한마취과학회지

Off-pump coronary surgery requires mechanical cardiac displacement, which results in bi-ventricular systolic and diastolic dysfunction. Although transient, subsequent hemodynamic deterioration can be associated with poor prognosis and, in extreme cases, emergency conversion to on-pump surgery, which is associated with high morbidity and mortality. Thus, appropriate decision-making regarding whether the surgery can be proceeded based on objective hemodynamic targets is essential before coronary arteriotomy. For adequate hemodynamic management, avoiding myocardial oxygen supply-demand imbalance, which includes maintaining mean arterial pressure above 70 mmHg and preventing an increase in oxygen demand beyond the patient’s coronary reserve, must be prioritized. Maintaining mixed venous oxygen saturation above 60%, which reflects the lower limit of adequate global oxygen supply-demand balance, is also essential. Above all, severe mechanical cardiac displacement incurring compressive syndromes, which cannot be overcome by adjusting major determinants of cardiac output, should be avoided. An uncompromising form of cardiac constraint can be ruled out as long as the central venous pressure is not equal to or greater than the pulmonary artery diastolic (or occlusion) pressure, as this would reflect tamponade physiology. In addition, transesophageal echocardiography should be conducted to rule out mechanical cardiac displacement-induced ventricular interdependence, dyskinesia, severe mitral regurgitation, and left ventricular outflow tract obstruction with or without systolic motion of the anterior leaflet of the mitral valve, which cannot be tolerated during grafting. Finally, the ascending aorta should be carefully inspected for gas bubbles to prevent hemodynamic collapse caused by a massive gas embolism obstructing the right coronary ostium.

Bilateral versus Single Internal Thoracic Artery Grafting Strategies Supplemented by Radial Artery Grafting

Purpose@#It is unclear if a second or third arterial graft can improve clinical outcomes in coronary artery bypass graft surgery. We compared the outcomes of bilateral internal thoracic artery (BITA) plus radial artery (RA) grafting versus left internal thoracic artery (LITA) plus RA grafting after off-pump coronary artery bypass grafting. @*Materials and Methods@#Between January 2009 and December 2020, a total of 3007 patients with three-vessel coronary artery disease who underwent off-pump coronary artery bypass were analyzed. Among them, 971 patients received total arterial grafting using LITA. We divided the patients into two groups [group A, BITA+RA grafting (n=227) and group B, LITA+RA grafting (n=744)], and compared the survival and major adverse cardiac and cerebrovascular event (MACCE) rates between the two groups at 10 years. @*Results@#After risk adjustment with inverse probability treatment weighting methods, the freedom from all-cause mortality was 93.1% and 88.3% in groups A and B, respectively (p=0.140). The freedom from MACCE rates were 68.3% and 89.0%, respectively (p<0.0001). LITA plus RA grafting [hazard ratio (HR): 1.3, 95% confidence interval (CI): 1.05–2.37, p=0.025] and incomplete revascularization (HR 1.2, 95% CI: 0.70–2.15, p=0.046) were significant risk factors for MACCEs in multivariable Cox regression analysis. @*Conclusion@#The rates of MACCEs were lower with LITA plus RA grafting than with BITA plus RA grafting in total arterial revascularization. Furthermore, complete revascularization improved long-term outcomes following total arterial grafting.

Clinical Outcomes of Endoscope-Assisted Pulmonary Endarterectomy for Chronic Thromboembolic Pulmonary Hypertension

Purpose@#Pulmonary thromboembolism is a potentially life-threatening condition in patients with heart disease; however, limited studies discussing long-term outcomes exist. This study aimed to investigate the long-term outcomes of pulmonary endarterectomy (PEA) in patients with chronic thromboembolic pulmonary hypertension (CTEPH), focusing on the improvement of functional class and right ventricular (RV) pressure. @*Materials and Methods@#Clinical data of patients with CTEPH were obtained from Yonsei Hospital between May 2012 and December 2021, and reviewed retrospectively. Twenty-six patients underwent endoscope-guided PEA during the study period, and the mean follow-up duration was 24.8±23.4 months. @*Results@#After PEA, most patients (88.5%) were weaned from inotropes without extracorporeal membrane oxygenation support during the first few days. Two patients (7.6%) had cerebrovascular accidents without neurological deficits. On echocardiography, the RV systolic pressure and tricuspid regurgitation grades significantly improved (p<0.001). Furthermore, the mean left ventricle end-diastolic diameter was significant increased (p=0.003), and the left ventricular end-systolic diameter increased (p<0.001). The median intensive care unit stay was 3.0±9.4 days, and median hospital stay 16.0±26.5 days. The 5-year survival rate was 95.5%, and the 5-year freedom rate of cardiac death was 100%. There was a marked improvement in New York Heart Association (NYHA) status (p<0.001). Cox regression suggested that the main pulmonary artery (MPA) involvement is a significant predictor of nonimprovement in functional class post-PEA. @*Conclusion@#Mortality rates are low and patients experience a marked improvement in NYHA class and health status after PEA. Moreover, MPA involvement may affect functional outcomes.

Outcome of Extracorporeal Ventricular Assist Device for Cardiogenic Shock as a Bridge to Transplantation

Background@#The extracorporeal ventricular assist device (e-VAD) system is designed for left ventricular support using a permanent life support console. This study aimed to determine the impact of temporary e-VAD implantation bridging on posttransplant outcomes. @*Methods@#We reviewed the clinical records of 6 patients with the Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) profile 1, awaiting heart transplantation, who were provided with temporary e-VAD from 2018 to 2019. The circuit comprised a single centrifugal pump without an oxygenator. The e-VAD inflow cannula was inserted into the apex of the left ventricle, and the outflow cannula was positioned in the ascending aorta. The median follow-up duration was 8.4±6.9 months. @*Results@#After e-VAD implantation, lactate dehydrogenase levels significantly decreased, and Sequential Organ Failure Assessment scores significantly improved. Bedside rehabilitation was possible in 5 patients. After a mean e-VAD support duration of 14.5±17.3 days, all patients were successfully bridged to transplantation. After transplantation, 5 patients survived for at least 6 months. @*Conclusion@#e-VAD may reverse end-organ dysfunction and improve outcomes in INTERMACS I heart transplant patients.

Concomitant Wrapping of a Moderately Dilated Ascending Aorta during Aortic Valve Replacement: Postoperative Remodeling of a Distinctive Aorta

Bioptome Perforation at Superior Vena Cava Anastomosis Site in Transplanted Heart

No abstract available.

Effect of Patient-Prosthesis Mismatch in Aortic Position on Late-Onset Tricuspid Regurgitation and Clinical Outcomes after Double Valve Replacement

PURPOSE: Significant late-onset tricuspid regurgitation (TR) is unfortunately common after double valve replacement (DVR); however, its underlying factors remain undefined. We evaluated the effect of aortic patient-prosthesis mismatch (PPM) on late-onset TR and clinical outcomes after DVR. MATERIALS AND METHODS: Of the 2392 consecutive patients who underwent aortic valve replacement between January 1990 and May 2014 at our institution, we retrospectively studied 462 patients who underwent DVR (excluding concomitant tricuspid valvular annuloplasty or replacement). Survival and freedom from grade >3 TR were compared between PPM (n=152) and non-PPM (n=310) groups using the Kaplan-Meier method. RESULTS: Although the overall survival rates were similar between the two groups at 5 and 10 years (95%, 91% vs. 96%, 93%, p=0.412), grade >3 TR-free survival was significantly lower in the PPM group (98%, 91% vs. 99%, 95%, p=0.014). Small body-surface area, atrial fibrillation, PPM, and subaortic pannus were risk factors for TR progression. However, aortic prosthesis size and trans-valvular pressure gradient were not significant factors for either TR progression or overall survival. CONCLUSION: Aortic PPM in DVR, regardless of mitral prosthesis size, was associated with late TR progression, but was not significantly correlated with overall survival. Therefore, we recommend careful echocardiographic follow-up for the early detection of TR progression in patients with aortic PPM in DVR.

Effect of Rosuvastatin on Bovine Pericardial Aortic Tissue Valve Calcification in a Rat Subdermal Implantation Model

BACKGROUND AND OBJECTIVES: There are pathophysiologic similarities between calcification and atherosclerosis because both are the product of an active inflammatory process. The aim of this study was to examine the effects of statin treatment on calcification in bovine pericardial tissue valves. MATERIALS AND METHODS: Forty Sprague-Dawley rats were randomly divided into 4 groups according to hypercholesterolemia induction and statin intake (Group 1, n=10: normal diet without statin treatment, Group 2, n=10: normal diet with statin treatment, Group 3, n=10: high fat diet without statin treatment, Group 4, n=10: high fat diet with statin treatment). Serum lipid levels were measured just before the experiment and after 4 and 12 weeks. Bovine pericardial tissue valve cusps were surgically implanted in rat dorsal subcutis at 4 weeks. After the surgery, statin was administered daily to Groups 2 and 4. Serum interleukin-6 (IL-6) level was measured at 5 weeks. Cusps were explanted at 12 weeks and calcium levels were determined by atomic absorption spectroscopy. RESULTS: Mean IL-6 was significantly higher in Group 3 at 5 weeks (7.14, 2.03, 31.70, and 6.90 pg/dL for each group, respectively). Mean calcium level in Group 3 was significantly higher among groups but Group 4 was significantly lower compared to Group 3 and was similar to Group 1, 2 (1.86, 1.92, 2.55, and 1.80 mg/g for each group, respectively, p<0.01). CONCLUSION: Hypercholesterolemia may be a significant risk factor for bovine pericardial valve calcification. Statin treatment significantly attenuated calcification of bovine pericardial valve tissue in a rat subdermal implantation model and might prolong the durability of bioprostheses.

Combined Bilateral Lung Transplantation and Off-Pump Coronary Artery Bypass

Coronary artery disease has historically been a contraindication to lung transplantation. We report a successful combined bilateral lung transplantation and off-pump coronary artery bypass in a 62-year-old man. The patient had a progressive decline in lung function due to idiopathic pulmonary fibrosis and a history of severe occlusive coronary artery disease.

Chondrosarcoma of the Heart

Chondrosarcoma is a rare entity of malignant tumor which arises from cartilaginous tissue, and the literatures on this disease are scarce. The first-line of treatment for cardiac chondrosarcoma is surgery. Due to early local recurrence and distant metastasis, the prognosis is poor even after complete surgical excision. We present a case of chondrosarcoma in the left atrium causing functional mitral stenosis which required urgent surgical intervention, and the successful treatment outcome.

Endovascular Repair versus Open Repair for Isolated Descending Thoracic Aortic Aneurysm

PURPOSE: To compare the outcomes of thoracic endovascular aortic repair (TEVAR) with those of open repair for descending thoracic aortic aneurysms (DTAA). MATERIALS AND METHODS: We compared the outcomes of 114 patients with DTAA and proximal landing zones 3 or 4 after TEVAR to those of 53 patients after conventional open repairs. Thirty-day and late mortality were the primary endpoints, and early morbidities, aneurysm-related death, and re-intervention were the secondary endpoints. RESULTS: The TEVAR group was older and had more incidences of dissecting aneurysm. The mean follow-up was 36+/-26 months (follow-up rate, 97.8%). The 30-day mortality in the TEVAR and open repair groups were 3.5% and 9.4% (p=0.11). Perioperative stroke and paraplegia incidences were similar between the groups [5.3% vs. 7.5% (p=0.56) and 7.5% vs. 3.5% (p=0.26), respectively]. Respiratory failure occurred more in the open repair group (1.8% vs. 26.4%, p<0.01). The incidence of acute kidney injury requiring dialysis was higher in the open repair group (1.8% vs. 9.4%, p<0.01). The cumulative survival rate was higher in the TEVAR group at 2 to 5 years (79.6% vs. 58.3%, p=0.03). The free from re-intervention was lower in the TEVAR group (65.3% vs. 100%, p=0.02), and the free from aneurysm-related death in the TEVAR and open repair groups were 88.5% and 86.1% (p=0.45). CONCLUSION: TEVAR is safe and effective for treating DTAAs with improved perioperative and long-term outcomes compared with open repair.

Early and Midterm Outcome of Redo Coronary Artery Bypass Grafting: On-Pump versus Off-Pump Bypass

BACKGROUND: Redo coronary artery bypass grafting (CABG) is still associated with increased morbidity and mortality as compared to the first-time operation. Further, the application of the off-pump technique to redo CABG is limited due to technical difficulties. The aim of this retrospective study was to analyze early and midterm results after redo CABG and compare the outcome of redo on-pump and off-pump CABG. METHODS: From June 1996 to October 2011, elective redo CABG was performed in 32 patients. Mean age was 64.8 years (on pump 64.3 years vs. off pump 65.5 years; p=0.658), and 21 patients were male. Among these patients, 14 (43.8%) underwent on-pump CABG, and 18 (56.2%) underwent off-pump CABG. RESULTS: Internal thoracic artery was used in 22 patients (68.8%), and total arterial revascularization was achieved in 17 patients (53.1%). The average number of distal anastomoses was 2.13, and the rate of incomplete revascularization was 43.8%. The rate of total arterial revascularization was higher in the off-pump group (14.3% vs. 83.3%, p<0.001), and the use of saphenous vein graft was more in the on-pump group (78.6% vs. 16.7%, p<0.001). Overall hospital mortality was 3.1% (n=1) and was comparable in both groups (on pump 7.1% vs. off pump 0%; p=0.249). Postoperative complications occurred in 9 patients (64.2%), and the rate of complications was high in the on-pump group without statistical significance (64.2% vs. 33.3%, p=0.082). The mean follow-up duration was 5.4 years, and overall survival at 10 years was 86.0%+/-10.5%. There was no significant difference in the 10-year survival rate between the two groups (79.6% vs. 100%, p=0.225). CONCLUSION: Redo CABG can be safely performed with acceptable mortality. Redo off-pump coronary artery bypass is feasible with low mortality and morbidity, comparable target vessel bypass grafting, and long-term survival. The off-pump technique might be considered a safe option for redo CABG in high-risk patients.

Effects of Some Pesticides on Development of Ascaris suum Eggs

To evaluate the effects of pesticides to parasite eggs, Ascaris suum eggs were incubated with 5 different pesticides (1:1,500-1:2,000 dilutions of 2% emamectin benzoate, 5% spinetoram, 5% indoxacarb, 1% deltamethrin, and 5% flufenoxuron; all v/v) at 20degrees C for 6 weeks, and microscopically evaluated the egg survival and development on a weekly basis. The survival rate of A. suum eggs incubated in normal saline (control eggs) was 90+/-3% at 6 weeks. However, the survival rates of eggs treated with pesticides were 75-85% at this time, thus significantly lower than the control value. Larval development in control eggs commenced at 3 weeks, and 73+/-3% of eggs had internal larvae at 6 weeks. Larvae were evident in pesticide-treated eggs at 3-4 weeks, and the proportions of eggs carrying larvae at 6 weeks (36+/-3%-54+/-3%) were significantly lower than that of the control group. Thus, pesticides tested at levels similar to those used in agricultural practices exhibited low-level ovicidal activity and delayed embryogenesis of A. suum eggs, although some differences were evident among the tested pesticides.

Effect of Postoperative Constrictive Physiology on Early Outcomes after Off-Pump Coronary Artery Bypass Grafting

BACKGROUND: Constrictive pericarditis after coronary artery bypass surgery has been known to affect cardiac output by limiting diastolic ventricular filling. We aimed to assess the influence of postoperative constrictive physiology on the early outcomes of patients undergoing off-pump coronary artery bypass grafting (OPCAB). MATERIALS AND METHODS: Between January 2008 and July 2011, 903 patients underwent an isolated OPCAB and postoperative transthoracic-echocardiography. The patient cohort was classified into two groups: group A, constrictive physiology and group B, control group without constrictive physiology. Early outcomes were analyzed between the two groups. RESULTS: Of the total 903 patients, group A consisted of 153 patients (16.9%). The amount of blood loss in group A during the postoperative 24 hours was greater than that of group B, but this was not statistically significant (p=0.20). No significant differences were found in the mortality rates (group A, 0.6%; group B, 1.4%; p=0.40) and 30-day major adverse cardiac and cerebrovascular events (MACCEs; group A, 3.3%; group B, 6.1%; p=0.42). CONCLUSION: Postoperative constrictive physiology does not affect 30-day MACCEs or other major complications after OPCAB. The results of this study suggest that patients with early postoperative constrictive physiology do not need medical or surgical treatment, and that conservative care is sufficient.

Comparison of Radial Artery and Saphenous Vein Composite Y Grafts during Off-pump Coronary Artery Bypass

BACKGROUND: The safety and efficacy of arterial composite grafts for total arterial revascularization have been demonstrated. The saphenous vein (SV) is a widely used graft because of its accessibility, sufficient length, and ease of manipulation. Our aim was to compare mid-term outcomes of saphenous vein Y-grafts with radial artery Y-grafts joined by anastomosis to the left internal thoracic artery. MATERIALS AND METHODS: Records of off-pump coronary artery bypass grafting with composite Y-grafts based on the left internal thoracic artery technique in 552 patients were analyzed retrospectively. After propensity score matching, 79 radial arterial (RA) composite grafts (RA group) and 79 saphenous vein composite grafts (SV group) were compared. The duration of mean follow-up was 24.6+/-14.6 months (range, 1 to 55 months). RESULTS: There were no differences in surgical mortality, all-cause mortality, or morbidity among the groups. Rates of 4-year survival were 91.7% and 96.3% in the RA and SV groups, respectively (p=0.519). The coronary reintervention-free survival rate and freedom from major adverse cardiovascular or cerebrovascular events were similar in the two groups (p=0.685, p=0.564). CONCLUSION: Construction of composite Y-grafts using the radial artery or saphenous vein showed similar mid-term results. Long-term follow-up and randomized trials will be needed to confirm our present conclusions.

Primary Cardiac Angiofibroma

Cardiac Angiofibroma is an uncommon intracardiac tumor. Thus far, only 4 cases of the rare intracardiac tumor have been reported. The present case-report describes an intracardiac angiofibroma in a 57-year-old healthy female. The patient was incidentally diagnosed with a left ventricle mass during echocardiography. We performed cardiac imaging, surgical excision and histological evaluation of the mass. The angiofibroma demonstrated features different from the relatively common cardiac tumors such as fibroma, myxoma and angiosarcoma. The cardiac MRI showed slightly high signal intensity on both T1 and T2, with the central core of lower signal intensity. The resected tumor was a whitish and rubbery mass. Histologically, the tumor showed the benign vascular proliferations associated with the surrounding collagen deposition.

Clinical Experience with the Bentall Procedure: 28 Years

PURPOSE: We retrospectively analyzed 28 years of experience with the Bentall procedure in patients with aortic valve, aortic root, and ascending aortic disease. MATERIALS AND METHODS: Between March 1982 and December 2010, a total of 218 patients underwent the Bentall procedure using a composite valved conduit. The "inclusion technique" was used in 30 patients (13.8%), the "open-button technique" in 181 patients (83.0%), and the Cabrol technique in 7 patients (3.2%). RESULTS: The early mortality rate was 5.5% (12/218). The mean follow-up duration was 108.0+/-81.0 months (range: 1-329 months). Seven patients required re-operation, and 1 patient required stent graft insertion at the descending thoracic aorta for progression of aortic arch or descending thoracic aortic dissection or aneurysm after the first operation, and 5 of them had Marfan syndrome. Kaplan-Meier estimated survival rates at 1, 5, 10, 20, and 25 years were 90.4%, 82.7%, 77.6%, 65.3%, and 60.3%, respectively. Freedom from reoperation rates at 1, 5, 10, 20, and 25 years were 99.0%, 98.3%, 95.5%, 90.8%, and 90.8%, respectively. CONCLUSION: In our experience, the Bentall procedure provided optimal survival with improved functional status. The disease of the aorta may progress, especially in patients with Marfan syndrome. Therefore, careful follow-up with regular computed tomography angiograms should be performed in these patients.

Long Term Results of ST-Segment Elevation Myocardial Infarction versus Non-ST-Segment Elevation Myocardial Infarction after Off-Pump Coronary Artery Bypass Grafting: Propensity Score Matching Analysis

There is no consensus as to which acute myocardial infarction subtype poses a greater risk after coronary artery bypass grafting (CABG). We compared the early and the long term results of off-pump coronary artery bypass grafting (OPCAB) between patients with STEMI (group I, n = 83), and NSTEMI (group II, n = 237). Group I had higher EuroSCORE, prevalence of emergency surgery, preoperative intra-aortic balloon pump use, preoperative emergency percutaneous transluminal coronary angioplasty, and preoperative thrombolytic use than group II. There were no significant differences in 30-day mortality and major adverse cardiac and cerebrovascular event (MACCE) between groups. Overall 8-yr survival was 93% and 87% in groups I and II, respectively. Freedom from MACCE after 8 yr was 92% and 93% in groups I and II, respectively. After propensity score matching analysis, there were no significant differences in preoperative parameters, postoperative in-hospital outcomes, and long-term clinical outcomes. Surgical results of OPCAB in patients with acute myocardial infarction show good results in terms of long-term survival and freedom from MACCE, with no significant differences in clinical outcomes between STEMI and NSTEMI groups.

Quantitative Evaluation of Viability- and Apoptosis-Related Genes in Ascaris suum Eggs under Different Culture-Temperature Conditions

Ascaris suum eggs are inactivated by composting conditions; however, it is difficult to find functional changes in heat-treated A. suum eggs. Here, unembryonated A. suum eggs were incubated at 20degrees C, 50degrees C, and 70degrees C in vitro, and the gene expression levels related to viability, such as eukaryotic translation initiation factor 4E (IF4E), phosphofructokinase 1 (PFK1), and thioredoxin 1 (TRX1), and to apoptosis, such as apoptosis-inducing factor 1 (AIF1) and cell death protein 6 (CDP6), were evaluated by real-time quantitative RT-PCR. No prominent morphological alterations were noted in the eggs at 20degrees C until day 10. In contrast, the eggs developed rapidly, and embryonated eggs and hatched larvae began to die, starting on day 2 at 50degrees C and day 1 at 70degrees C. At 20degrees C, IF4E, PFK1, and TRX1 mRNA expression was significantly increased from days 2-4; however, AIF1 and CDP6 mRNA expression was not changed significantly. IF4E, PFK1, and TRX1 mRNA expression was markedly decreased from day 2 at 50degrees C and 70degrees C, whereas AIF1 and CDP6 mRNA expression was significantly increased. The expressions of HSP70 and HSP90 were detected for 9-10 days at 20degrees C, for 3-5 days at 50degrees C, and for 2 days at 70degrees C. Taken together, incremental heat increases were associated with the rapid development of A. suum eggs, decreased expression of genes related to viability, and earlier expression of apoptosis-related genes, and finally these changes of viability- and apoptosis-related genes of A. suum eggs were associated with survival of the eggs under temperature stress.

Two Cases of Ascending Aortic Intramural Hematoma Combined with Cardiac Tamponade Treated with Different Strategies

Aortic intramural hematoma (IMH) is classically defined as a variation of aortic dissection where blood collects within the aortic media without the presence of an intimal flap. Ascending IMH is known to have worse clinical outcomes than IMH of the descending aorta or aortic arch. Therefore, some patients with higher risk of disease progression require surgical corrections. However, the indications and the benefits of surgical management of ascending IMH, compared with medical treatment only, have not yet been established. We present two cases of IMH in the ascending aorta that presented with cardiac tamponade; patients were treated differently according to risk factors.