Changes in aortic growth rate and factors influencing aneurysmal dilatation after uncomplicated acute type B aortic dissection.

OBJECTIVES: The aim of this study was to evaluate changes in aortic growth rate and factors influencing aneurysmal dilatation after uncomplicated acute type B aortic dissection (ABAD). METHODS: Medically treated patients with uncomplicated ABAD between September 2004 and January 2020 were retrospectively reviewed. Diameters of 6 different sites in the descending aorta were measured and aortic growth rate was calculated according to the time interval. Factors associated with aneurysmal changes were also investigated. RESULTS: This study enrolled a total of 105 patients who underwent >2 serial computed tomography with a mean follow-up duration of 35.4 (12.1-77.4) months. The mean overall growth rates of the proximal descending thoracic aorta (DTA), mid-DTA, distal DTA, proximal abdominal aorta, maximal DTA and maximal abdominal aorta were 0.6 (1.9), 2.9 (5.2), 2.1 (4.0), 1.2 (2.2), 3.3 (5.6) and 1.4 (2.5) mm/year, respectively. The growth rate was higher at the early stage. It decreased over time. Growth rates of proximal DTA, mid-DTA, distal DTA, proximal abdominal aorta, maximal DTA, and maximal abdominal aorta within 3 months after dissection were 1.3 (9.6), 12.6 (18.2), 7.6 (11.7), 5.9 (7.5), 16.7 (19.8) and 6.8 (8.9) mm/year, respectively. More than 2 years later, they were 0.2 (0.6), 1.6 (1.6), 1.2 (1.3), 0.9 (1.4), 1.7 (1.9) and 1.2 (1.7) mm/year, respectively. Factors associated with aneurysmal changes after uncomplicated ABAD included an elliptical true lumen (odds ratio = 3.16; 95% confidence interval: 1.19-8.41; P = 0.021) and a proximal entry >10 mm (odds ratio = 3.08; 95% confidence interval: 1.09-8.69; P = 0.034) on initial computed tomography imaging. CONCLUSIONS: The aortic growth rate was higher immediately after uncomplicated ABAD but declined eventually. Patients with an elliptical true lumen and a large proximal entry might be good candidates for early endovascular intervention after uncomplicated ABAD.

Zone 2 hybrid thoracic endovascular aortic repair: Is it a good option for all types of thoracic aortic disease?

BACKGROUND: Zone 2 thoracic endovascular aortic repair (TEVAR) is performed for the treatment of various thoracic aortic diseases involving the left subclavian artery. This study aimed to analyze the late clinical outcomes of zone 2 hybrid TEVAR according to the various indications. METHODS: A total of 48 patients who underwent zone 2 TEVAR at our institution between December, 2010 and July, 2020 were enrolled. The indications were aortic aneurysm (AA, n = 15), acute type B aortic dissection (AD, n = 14), penetrating aortic ulcer (PAU, n = 8), traumatic aortic injury (TAI, n = 8), and others (n = 3). The clinical outcomes including early complications and mid-term aortic measurements were retrospectively reviewed. RESULTS: The technical success rate was 100% and in-hospital mortality occurred in one patient. The early postoperative complications included stroke (n = 1), transient spinal cord ischemia (n = 1), neck wound hematoma (n = 1), and left phrenic or vagus nerve injury (n = 9). In patients with AD, positive remodeling was observed in ten patients (76.9%) (false lumen regression in the entire or thoracic aorta [n = 9], false lumen thrombosis in the thoracic aorta [n = 1]). However, in patients with AA, increased aneurysm was found in six patients (40%). Persistent aneurysmal growth was found in patients with a maximal aortic diameter of > 60 mm on initial imaging (4/6, 50%). No aortic expansion was observed in those with TAI or PAU. Endoleak was noted in five patients (10.4%), and among them, aortic reintervention was required only in patients with large AAs. CONCLUSIONS: Zone 2 hybrid TEVAR was associated with an acceptable early complication rate and provided acceptable mid-term aortic results for patients with AD, PAU, and TAI. However, patients with large AAs were at increased risk of aortic reintervention. In cases of large AA, clinicians should carefully consider whether zone 2 hybrid TEVAR or open surgical repair will be more effective for the patient.

Influence of Ipsilateral Graft Inflow to Arteriovenous Fistula for Hemodialysis in Coronary Bypass Surgery.

In coronary artery bypass grafting (CABG) for patients on hemodialysis, there has been concern about "coronary steal". This study aims to evaluate the influence of using an in situ internal thoracic artery (ITA) ipsilateral to a preexisting arteriovenous fistula (AVF) in dialysis-dependent patients undergoing CABG. Between 2004 and 2018, dialysis-dependent patients with AVFs who underwent CABG were enrolled. According to the locational relationship of AVFs and in situ ITA grafts, the patients were divided into the ipsilateral group (n = 22) and the contralateral group (n = 21). Inverse probability weighting analysis was used to estimate and compare the late clinical outcomes. The late cardiac-related adverse events were not significantly different between the two groups: "major adverse cardiovascular and cerebrovascular events (MACCE)" (p = 0.090), "composite outcome of recurrent angina and coronary re-intervention" (p = 0.600). The in situ ITA graft of CABG on the ipsilateral side to AVF was not a significant risk factor for MACCE or the composite outcome of recurrent angina and coronary re-intervention. There was no statistically significant difference in the graft patency between the groups. Therefore, it might not be necessary to avoid using an in situ ITA on the ipsilateral side of an upper-arm AVF for optimal coronary artery bypass grafting in dialysis-dependent patients.

Robot-Assisted Repair of Atrial Septal Defect: A Comparison of Beating and Non-Beating Heart Surgery.

BACKGROUND: Robot-assisted repair of atrial septal defect (ASD) can be performed under either beating-heart or non-beating-heart conditions. However, the risk of cerebral air embolism (i.e., stroke) is a concern in the beating-heart approach. This study aimed to compare the outcomes of beating- and non-beating-heart approaches in robot-assisted ASD repair. METHODS: From 2010 to 2019, a total of 45 patients (mean age, 43.4±14.6 years; range, 19-79 years) underwent ASD repair using the da Vinci robotic surgical system. Twenty-seven of these cases were performed on a beating heart (beating-heart group, n=27) and the other cases were performed on an arrested or fibrillating heart (non-beating-heart group, n=18). Cardiopulmonary bypass (CPB) was achieved via cannulation of the femoral vessels and the right internal jugular vein in all patients. RESULTS: Complete ASD closure was verified using intraoperative transesophageal echocardiography in all patients. Conversion to open surgery was not performed in any cases, and there were no major complications. All patients recovered from anesthesia without any immediate postoperative neurologic symptoms. In a subgroup analysis of isolated ASD patch repair (beating-heart group: n=22 vs. non-beating-heart group: n=5), the operation time and CPB time were shorter in the beating-heart group (234±38 vs. 253±29 minutes, p=0.133 and 113±28 vs. 143±29 minutes, p=0.034, respectively). CONCLUSION: Robot-assisted ASD repair can be safely performed with the beating-heart approach. No additional risk in terms of cerebral embolism was found in the beating-heart group.

Diameter change in completely remodelled proximal descending aorta after acute type I dissection repair: implications for estimating the pre-dissection size.

OBJECTIVES: Pre-dissection diameter of the proximal descending thoracic aorta (p-DTA), if available, would be the reference for determining the size of the stent graft or elephant trunk. Acute type B dissection is known to increase p-DTA diameter by 23% (Rylski factor). This study aimed to investigate the accuracy of estimating post-remodelling diameter of the p-DTA based on the Rylski factor and other post-dissection morphological parameters in acute type I dissection, based on the assumption that the post-remodelling diameter is similar to the pre-dissection diameter. METHODS: In 60 patients with acute type I dissection showing complete remodelling of the p-DTA false lumen after surgical repair, preoperative and post-remodelling computed tomography scans were reviewed. Parameters, including maximal true lumen diameter (TLDmax) and aortic area-derived diameter divided by the Rylski factor (AoDRylski), were measured at the p-DTA. RESULTS: After complete remodelling, p-DTA diameter decreased by 4.1 mm (P < 0.001). The equivalent to the Rylski factor was 15%. Both TLDmax and AoDRylski frequently showed ≥2 mm discrepancy from post-remodelling aortic diameter (36.7% and 48.3%, respectively, P = 0.30). When 2 parameters coincided within 2 mm, two-third of their estimations were accurate. AoDRylski was more accurate than TLDmax in patients with a large extent of circumferential dissection, and vice versa with less circumferential dissection (P = 0.027). CONCLUSIONS: Prediction of post-remodelling aortic diameter relying on a single morphologic parameter carries a substantial risk of overestimation and underestimation. Evaluation based on the extent of circumferential dissection together with the 2 parameters may provide a more reliable estimation.

Clinical Outcomes of Surgical Repair with a Composite Graft for Abdominal Aortic Aneurysm Accompanied by Iliac Artery Aneurysm.

BACKGROUND: Iliac artery aneurysm is frequently found in patients undergoing surgical repair of an abdominal aortic aneurysm. The use of commercial bifurcated grafts is insufficient for aorto-biiliac replacement with complete iliac artery aneurysm resection. We evaluated the effectiveness of handmade composite grafts for this purpose. METHODS: A total of 233 patients underwent open surgery for abdominal aortic aneurysm between 2003 and 2019, including 155 patients (67%) treated with commercial grafts and 78 patients (33%) treated with handmade composite grafts. Their operative characteristics, postoperative outcomes, and late outcomes were retrospectively reviewed. RESULTS: The early mortality rate did not differ significantly between the groups. On average, the handmade composite graft technique took approximately 15 minutes longer than the commercial graft technique (p=0.037). Among patients who underwent elective surgery, no significant differences between the conventional and composite groups were observed in the major outcomes, including red blood cell transfusion volume (2.8±4.7 units vs. 3.1±4.7 units, respectively; p=0.680), reoperation for bleeding (2.7% vs. 3.1%, respectively; p>0.999), bowel ischemia (0% vs. 1.6%, respectively; p=0.364), and intensive care unit stay duration (1.9±6.6 days vs. 1.6±2.4 days, respectively; p=0.680). The incidence of target vessel occlusion also did not differ significantly between groups. CONCLUSION: The increased technical demand involved with handmade composite grafting did not negatively impact the outcomes. This technique may be a viable option because it overcomes problems associated with commercial grafts.

The Impact of an Attending Intensivist on the Clinical Outcomes of Patients Admitted to the Cardiac Surgical Intensive Care Unit after Coronary Artery Bypass Grafting.

BACKGROUND: We aimed to investigate the associations of critical care provided in a cardiac surgical intensive care unit (CSICU) staffed by an attending intensivist with improvements in intensive care unit (ICU) quality and reductions in postoperative complications. METHODS: Patients who underwent elective isolated coronary artery bypass grafting (CABG) between January 2007 and December 2012 (the control group) were propensity-matched (1:1) to CABG patients between January 2013 and June 2018 (the intensivist group). RESULTS: Using propensity score matching, 302 patients were extracted from each group. The proportion of patients with at least 1 postoperative complication was significantly lower in the intensivist group than in the control group (17.2% vs. 28.5%, p=0.001). In the intensivist group, the duration of mechanical ventilation (6.4±13.7 hours vs. 13.7±49.3 hours, p=0.013) and length of ICU stay (28.7±33.9 hours vs. 41.7±90.4 hours, p=0.018) were significantly shorter than in the control group. The proportions of patients with prolonged mechanical ventilation (2.3% vs. 7.6%, p=0.006), delirium (1.3% vs. 6.3%, p=0.003) and acute kidney injury (1.3% vs. 5.3%, p=0.012) were significantly lower in the intensivist group than in the control group. CONCLUSION: A transition from an open ICU model with trainee coverage to a closed ICU model with attending intensivist coverage can be expected to yield improvements in CSICU quality and reductions in postoperative complications.

Frailty Index is Associated with Adverse Outcomes after Aortic Valve Replacement in Elderly Patients.

BACKGROUND: This study was conducted to evaluate the prognostic value of the frailty index based on routine laboratory data (FI-L) in elderly patients who underwent surgical aortic valve replacement (SAVR). METHODS: A total of 154 elderly patients (≥ 75 years) (78.7 ± 3.6 years; men:women = 78:76) who underwent aortic valve replacement with stented bioprosthesis between 2001 and 2018 were enrolled. The FI-L was calculated as the proportion of abnormal results out of 32 items based on laboratory tests, pulse rate and blood pressure. The primary outcome was all-cause mortality. Secondary outcomes included operative mortality and aortic valve-related events (AVREs) during follow-up. The predictive values of FI-L for the early and late outcomes were evaluated using logistic regression and Cox proportional hazards models, respectively. The median follow-up duration was 40 months (interquartile, 15-74). RESULTS: The operative mortality rate was 3.9% (n = 6). Late death occurred in 29 patients. The overall survival (OS) rates at 5, 10, and 15 years were 83.3%, 59.0%, and 41.6%, respectively. The AVREs occurred in 28 patients and the freedom rates from AVREs at 5, 10, and 15 years were 79.4%, 72.7%, and 52.9%, respectively. Multivariable analyses demonstrated that FI-L was a significant factor for OS (hazard ratio, 1.075; 95% confidence interval, 1.040-1.111). A minimal P value approach showed that a FI-L of 25% was the best cutoff value to predict OS after SAVR. CONCLUSION: The FI-L is significantly associated with early and long-term outcomes after SAVR in elderly patients. Frailty rather than a patient's age should be considered in the decision-making process for SAVR in elderly patients.

Partial Sternectomy to Prevent Rastelli Conduit Compression in Patients With Conotruncal Anomalies.

This report describes 2 cases of redo cardiac surgery in adult patients with conotruncal anomalies (double-outlet right ventricle and transposition of the great arteries) with pulmonary stenosis who underwent the Rastelli procedure in childhood. Although the Rastelli operation is one of the best options for the patients, conduit stenosis has occasionally developed secondary to compression by the anterior chest wall. To prevent compression by the sternum, partial sternectomy with Rastelli conduit change was performed in these 2 patients.

Cardiopulmonary Bypass Strategies to Maintain Brain Perfusion during Lung Transplantation in a Patient with Severe Hypercapnia.

Herein, we report a case of lung transplantation in a patient with profound preoperative hypercapnia, focusing on the cardiopulmonary bypass strategy used for brain perfusion during the operation. We applied the pH-stat method for acid-base regulation, and thereby achieved the desired outcome without any neurologic deficit.

Aortic Valve Replacement for Aortic Stenosis in Elderly Patients (75 Years or Older).

BACKGROUND: This study evaluated the early and long-term outcomes of surgical aortic valve replacement (AVR) in elderly patients in the era of transcatheter aortic valve implantation. METHODS: Between 2001 and 2018, 94 patients aged ≥75 years underwent isolated AVR with stented bioprosthetic valves for aortic valve stenosis (AS). The main etiologies of AS were degenerative (n=63) and bicuspid (n=21). The median follow-up duration was 40.7 months (range, 0.6-174 months). RESULTS: Operative mortality occurred in 2 patients (2.1%) and paravalvular leak occurred in 1 patient. No patients required permanent pacemaker insertion after surgery. Late death occurred in 11 patients. The overall survival rates at 5 and 10 years were 87.2% and 65.1%, respectively. The rates of freedom from valve-related events at 5 and 10 years were 94.5% and 88.6%, respectively. The Society of Thoracic Surgeons (STS) score (p=0.013) and chronic kidney disease (p=0.030) were significant factors affecting long-term survival. The minimal p-value approach demonstrated that an STS score of 3.5% was the most suitable cut-off value for predicting long-term survival. CONCLUSION: Surgical AVR for elderly AS patients may be feasible in terms of early mortality and postoperative complications, particularly paravalvular leak and permanent pacemaker insertion. The STS score and chronic kidney disease were associated with long-term outcomes after AVR in the elderly.

Lung Volume Reduction Surgery for Respiratory Failure in Infants With Bronchopulmonary Dysplasia.

Lung volume reduction surgery (LVRS) can be performed in patients with severe emphysematous disease. However, LVRS in pediatric patients has not yet been reported. Here, we report our experience with 2 cases of pediatric LVRS. The first patient was a preterm infant girl with severe bronchopulmonary dysplasia, pulmonary hypertension, and hypothyroidism. The emphysematous portion of the right lung was removed via sternotomy and right hemiclamshell incision. The patient was discharged on full-time home ventilator support for 3 months after the surgery. Since then, her respiratory function has improved continuously. She no longer needs oxygen supplementation or ventilator care. Her T-cannula was removed recently. The second patient was also a preterm infant girl with bronchopulmonary dysplasia. She was born with pulmonary hypertension and multiple congenital anomalies, including an atrial septal defect. Despite receiving the best supportive care, she could not be taken off the mechanical ventilator because of severe hypercapnia. We performed LVRS on the right lung via thoracotomy. She was successfully weaned off the mechanical ventilator 1 month after the surgery. She was discharged without severe complications at 3 months after the operation. At present, she is growing well with the help of intermittent home ventilator support. She can now tolerate an oral diet. Our experience shows that LVRS can be considered as a treatment option for pediatric patients with severe emphysematous lung. It is especially helpful for discontinuing prolonged mechanical ventilator care for patients with respiratory failure.

Epicardial permanent pacemaker implantation in the retrosternal space of a 2.3-kg infant.

Permanent pacemaker implantation in small infants can be challenging because of patient size and expected somatic growth. In our case, we used the retrosternal space as a generator pocket for an extremely low-birth-weight premature baby with autoantibody-associated congenital heart block born to a systemic lupus erythematosus mother.