Surgical 5-year Outcomes of Extra-Anatomical Bypass for Middle Aortic Syndrome: A Case Series.

BACKGROUND: Middle aortic syndrome is a rare disease. Several surgical treatments are available; however, the optimal treatment strategy and long-term outcomes remain unelucidated. We herein report the 5-year outcomes of six patients treated with extra-anatomical bypass surgery for middle aortic syndrome. CASE PRESENTATIONS: Between 2013 and 2016, six patients underwent extra-anatomical bypass for middle aortic syndrome at our institute: three had Takayasu's arteritis, one had vessel vasculitis, and two had middle aortic hypoplastic syndrome of unknown origin. The patients included five women and one man, with a mean age of 59.7 years. Four patients had uncontrolled hypertension and were receiving antihypertensive medications. The mean ankle-brachial pressure index was .61. The three patients with Takayasu's arteritis were hospitalized for congestive heart failure. These patients underwent bypass surgery from the descending aorta to the infrarenal abdominal aorta, and one also underwent concomitant heart surgery. The patient with microscopic polyangiitis underwent Y-grafting with an aortic aneurysmectomy. Subsequently, bypass surgery was performed from the descending aorta to the graft via the diaphragm. The two patients with unknown causes underwent bypass surgery from the proximal descending aorta to the distal descending thoracic aorta. There were no early or late deaths at the 5-year follow-up. We did not observe any changes in anastomotic site stenosis or new aneurysmal changes during the follow-up period. The number of antihypertensive medications was reduced in all cases, and critical symptoms, including headache, severe abdominal pain, claudication, and heart failure, improved in all patients. The ankle-brachial pressure index increased to 1.11 and did not change for five years. Renal function remained stable, and the brain natriuretic peptide level decreased from 302.8 to 74.5 pg/mL at follow-up. CONCLUSION: Extra-anatomical bypass for middle aortic syndrome is safe and effective, and can help prevent renal failure, and relieve critical ischemic symptoms.

Rapid decline in cardiac function in diabetic patients with calcified coronary artery disease undergoing hemodialysis: two case reports.

BACKGROUND: Clinical symptoms of patients on dialysis do not match the signs of coronary disease progression, making the prediction of the true progression of their medical condition in clinical settings difficult. Emergency and concomitant surgeries are significant risk factors of mortality following open-heart surgery in patients on hemodialysis. CASE PRESENTATION: We report two cases of successful coronary artery bypass grafting (CABG) in patients on dialysis with a history of cardiac surgery. The first case describes a 65-year-old woman who had undergone aortic valve replacement 2 years ago and was hospitalized urgently, because of a sudden decline in heart function and hypotension. She had moderate mitral regurgitation with right ventricular pressure of 66 mmHg and poor left ventricular function [left ventricular ejection fraction (LVEF), 40%]. Cineangiography revealed an increase in the rate of stenosis in the left main trunk, from 25 to 99% at admission, in addition to 100% occlusion in proximal left anterior descending artery (LAD) and 99% stenosis in the proximal left circumflex artery (LCX). We inserted an intra-aortic balloon pump preoperatively and performed emergency surgery (Euro II risk score, 61.7%; Society of Thoracic Surgeons (STS) risk score, 56.3%). The second case described a 78-year-old man who had undergone surgery for left atrial myxoma 4 years ago and was hospitalized urgently due to dyspnea, chest discomfort, and an LVEF of 44% (Euro II risk score, 40.7%; STS risk score, 33.2%). Cineangiography revealed an increase in the rate of stenosis in the proximal LAD, from 25% (4 years ago) to 90% at admission, in addition to 99% stenosis in proximal LCX and 95% stenosis in the posterolateral branch of LCX. Both patients underwent emergency CABG due to unstable hemodynamics and decreased left ventricular function despite regular dialysis. The surgeries were successful, and the patients were discharged without any complications. CONCLUSIONS: In patients with multiple comorbidities and those who undergo dialysis treatment, calcified lesions in coronary arteries can progress severely and rapidly without any symptoms, including chest pain. Close outpatient management involving nephrologists and the cardiovascular team is necessary for patients on dialysis.

Rapid-Deployment Aortic Valve Replacement for a Hemodialysis Patient with Prior Coronary Artery Bypass Grafting.

BACKGROUND: Aortic valve reoperation increases the risk of mortality and morbidity. The 2017 European Society of Cardiology guidelines for managing valvular heart disease with a previous heart surgery and intact bypass grafts consider patients with high surgical risk to be injury-prone during sternotomy. In high-risk patients with prior coronary artery bypass grafting, several authors have reported the noninferiority or superiority of transcatheter aortic valve replacement (TAVR) compared with surgical aortic valve replacement; however, in Japan, TAVR cannot be performed for patients on hemodialysis. In this study, we report a case of successful implantation of the new rapid-deployment bioprosthesis in a 65-year-old Japanese man on dialysis with prior coronary artery bypass grafting. METHODS: The rapid-deployment aortic valve system has demonstrated excellent hemodynamic performance, durability, and safety. However, implantation requires specific training and the analysis of preoperative 3D computed tomographic imaging. The cineangiography revealed patency of all grafts, and the saphenous vein graft (SVG) had overlapped the planned aortotomy position. By avoiding the anastomotic part of the SVG, we could perform rapid-deployment aortic valve replacement efficiently even if the aortic incision was repositioned, and the incision was smaller than planned. RESULTS: We used the 23-mm Intuity valve without an additional stitch, and the cardiopulmonary bypass and aortic cross-clamp times were only 52 and 39 minutes, respectively. CONCLUSION: This novel valve may be beneficial in complex combinational procedures for hemodialysis patients with prior coronary artery bypass grafting.

A new technique that prevents paravalvular leakage after aortic valve replacement using a rapid-deployment valve system.

BACKGROUND: We report our 1-year single-center experience of a new technique of aortic valve replacement using a rapid-deployment valve (RD-AVR) to avoid postoperative complications. We also report the unexpected pitfalls and handling techniques that we have seen in past cases. METHODS: We performed aortic valve replacement on 38 patients between May 2019 and April 2020. Their mean age was 74 years. The primary outcomes were in-hospital mortality and short-term results during a 1-year follow-up period, while the secondary outcomes were related to prosthetic valve function, especially paravalvular leakage (PVL). We further analyzed the relationship between the new technique and its outcomes. RESULTS: The mean operative time was 196 min. There were no in-hospital deaths, and the mean duration of postoperative hospital stay was 11.8 days. Valvular measurements using three-dimensional computed tomography were larger and more accurate than those measured using ultrasonic echocardiography. Postoperative RD-AVR prosthetic valve function was excellent. However, PVL occurred in four cases 1 week and 1 year postoperatively and regurgitation did not improve. A gap associated with PVL was identified below the right-noncoronary commissure. To prevent PVL, we additionally stitched this gap in the later 18 cases; there was no case of PVL and no new pacemaker implantation in these cases. CONCLUSIONS: PVL is more likely to occur if there is a gap below the R-N commissure, especially in cases with a large annulus; therefore, applying an additional stitch to the R-N commissure is extremely useful.

Comparison of modern risk scores in predicting operative mortality for patients undergoing aortic valve replacement for aortic stenosis.

BACKGROUND: The aim of our study was to examine and compare the predictive value of operative mortality of the European System for Cardiac Operative Risk Evaluation (EuroSCORE) II, the Society of Thoracic surgeons (STS) score, the Ambler score, and the Japan score in patients undergoing aortic valve replacement (AVR) for aortic stenosis (AS). METHODS: A total of 406 patients undergoing AVR with or without coronary artery bypass grafting (CABG, n=139) at our institution from August 2002 to December 2013 were enrolled in this cohort study. Accuracy of calibration and discrimination performance of four risk scores was assessed in the overall patient population and quartiles of each risk score. RESULTS: Operative mortality was 3.4% (n=14). The mean EuroSCORE II, STS score, Ambler score, and the Japan score were 3.1%, 4.9%, 5.7%, and 3.2%, respectively, giving observed-to-expected (O/E) ratio of 1.09, 0.69, 0.59, and 1.06. The C-statistics for operative mortality were 0.704 (EuroSCORE II), 0.781 (STS score), 0.709 (Ambler score), and 0.771 (Japan score). In the last quartile, the EuroSCORE II demonstrated excellent calibration (O/E ratio=0.97) and discrimination (C-statistic=0.904), and the STS score (O/E ratio=0.86, C-statistic=0.779) and the Japan score (O/E ratio=1.14, C-statistic=0.80) showed reasonable correlation. However, the risk calibration by the Ambler score in the last quartile was unacceptable (O/E ratio=0.60). CONCLUSIONS: The EuroSCORE II and the Japan score showed superior ability of calibration, but the STS score and the Ambler score overestimated the risk. However, the discrimination power was similar among the four risk scores. In the last quartile of risk, the EuroSCORE II gave an excellent predictive performance.

Should we consider surgical intervention for spinal cord ischemia due to acute type B aortic dissection?

We present a 46-year-old man with a sudden onset of severe back pain following leg pain. An emergent computed tomography showed acute type B aortic dissection. The true lumen was almost completely occluded because of compression of a massive thrombus in the false lumen. The patient developed paraplegia by the time he was taken into the operation room. After induction of anesthesia, partial cardiopulmonary bypass was initiated, and then the chest was opened via left thoracotomy. The entry was found in the distal aortic arch and was successfully repaired. The descending aorta was replaced with a Dacron graft and antegrade re-perfusion was established in the descending aorta three hours after the onset of paraplegia. The patient recovered uneventfully without any neurological deficit. Paraplegia caused by acute type B aortic dissection is a rare complication. Usually it is treated medically. However, if the true lumen is occluded due to a massive thrombus in the false lumen, multiple malperfusion of the distal organs may occur. In such a case, surgical intervention should be considered to resume antegrade perfusion in the descending aorta as soon as possible.