Yuji Sekine

Left atrial appendage contributes to left atrial booster function after the maze procedure: quantitative assessment with multidetector computed tomography

OBJECTIVE Although the left atrial appendage (LAA) is excised to prevent thrombosis in the maze procedure, it remains unclear whether LAA is retained in expectation of LAA booster function. Therefore, we quantitatively assessed LAA size and function after the maze procedure in patients with chronic atrial fibrillation (AF) and mitral valve disease (MVD), and compared with those in patients with sinus rhythm after coronary artery bypass grafting (CABG). METHODS We studied 23 patients (maze group: 65.0 + or - 9.2 (SD) years) undergoing the maze procedure for chronic AF and mitral valve surgery and 16 patients having sinus rhythm after CABG (CABG group: 66.5 + or - 9.3 years). The maze procedure was conducted by radiofrequency (RF) ablation and LAA was preserved in all cases. Left atrium (LA) and LAA volume and booster function were quantitatively evaluated by multidetector computed tomography (MDCT) at 11.7 + or - 10.4 months (maze group) and 16.8 + or - 19.9 months (CABG group) after the surgery. RESULTS In all 23 patients of the maze group, sinus rhythm was well restored. LAA was clearly visualised without thrombi in all 39 patients. The maximal LA volume in the maze group was 128.8 + or - 54.6 ml, being larger than 105.3 + or - 36.1 ml in the CABG group. LA ejection fraction (EF) in the maze group was 16.1 + or - 7.0%, being significantly lower than 26.8 + or - 8.7% in the CABG group. Meanwhile, the maximal LAA volume in the maze group was significantly larger (16.9 + or - 7.3 ml vs 8.4 + or - 4.7 ml), but LAA EF (34.1 + or - 12.8% vs 36.1 + or - 7.4%) was comparable in the two groups. CONCLUSION LAA largely contributes to LA booster function, particularly in the maze group, because LA booster function is deteriorated in this group of patients.

Haemolytic anaemia resulting from the surgical repair of acute type A aortic dissection

OBJECTIVES Haemolytic anaemia after acute aortic dissection surgery is extremely rare. We report 4 cases of haemolytic anaemia with different aetiologies. METHODS Four patients underwent emergency operation for acute type A aortic dissection and subsequently developed haemolytic anaemia. RESULTS Case 1: a 41-year old man underwent hemiarch replacement. We performed total arch replacement 3 years postoperatively, which revealed that haemolytic anaemia was induced by proximal anastomotic stenosis caused by inverted internal felt strip. Case 2: a 28-year old man diagnosed with Marfan syndrome underwent total arch replacement. Five months postoperatively, we noted severe stenosis at the previous distal anastomotic site, which caused the haemolytic anaemia, and performed descending thoracic aortic replacement for a residual dissecting aneurysm. Case 3: a 49-year old man underwent hemiarch replacement. Three years postoperatively, we performed total arch replacement for a residual dissecting aortic arch aneurysm and repaired a kinked graft responsible for haemolytic anaemia. Case 4: a 42-year old man underwent total arch replacement. Eighteen months later, we performed descending thoracic aortic replacement. We repaired a portion of the ascending aorta as haemolityc anaemia was induced by kinking of a total arch replacement redundant graft. CONCLUSIONS All the haemolityc anaemia patients were successfully released after surgical reintervention.

Predictors of paraplegia with current thoracoabdominal aortic aneurysm repair.

Background Although the results of surgical repair of thoracoabdominal aortic aneurysm continue to improve, the incidence of paraplegia remains within a wide range depending on each institution. The purpose of this study was to find predictors of paraplegia following thoracoabdominal aortic aneurysm repair in our institute, using the current spinal cord protection strategies. Methods From January 2007 to December 2011, 200 consecutive patients underwent thoracoabdominal aortic aneurysm repair. Of these, 24 (12%) had Crawford extent I repair, 82 (41%) had extent II, 51 (25.5%) had extent III, 10 (5%) had extent IV, and 33 (16.5%) had extent V (modified by Safi). Aortic dissection was present in 101 (50.5%) patients. Adjuncts used during the procedures included left heart bypass in all patients, cerebrospinal fluid drainage in 164 (82%), and intercostal artery reimplantation in 76 (38%). Results There were 20 (10%) hospital deaths including 6 (3%) within 30 days; hospital mortality was 8.8% in elective operations. Postoperative complications included paraplegia in 17 (8.5%) patients, stroke in 5 (2.5%), and acute renal failure requiring dialysis in 5 (2.5%). Logistic regression analysis revealed that significant factors for the development of paraplegia were preoperative hypotension (p = 0.005, odds ratio 18.5), intraoperative hypotension (p = 0.001, odds ratio 77.6), and an open distal anastomosis technique (p = 0.012, odds ratio 4.6). Conclusions The predictors of postoperative paraplegia in our institution were perioperative hypotension and an open distal anastomosis technique. Avoidance of these risk factors might diminish the incidence of postoperative paraplegia.

Hybrid procedure for a Kommerell's diverticulum in a right-sided aortic arch.

A rare case of an aneurysmal Kommerells diverticulum in a right-sided aortic arch was successfully treated using a hybrid procedure comprising total arch replacement and percutaneous stent grafting. A 65-year-old man with dysphagia was diagnosed with an ectatic right-sided aortic arch and a saccular aneurysm of the Kommerells diverticulum. Since its radical resection during a single surgery was unfeasible because of its complex configuration, a 2-stage procedure was adopted.

Surgical strategy for Kommerell’s diverticulum with aberrant subclavian artery: Reply

We appreciate the insightful comments of Saeed and colleagues and the opportunity to clarify a number of points about our work. As Saeed and colleagues point out, it is very important to determine the surgical indications for Kommerell’s diverticulum (KD) with an aberrant subclavian artery. Determining the surgical indications based solely on symptoms or the maximum aneurysm diameter is very difficult because KD remains rare. Because of the absence of prospective natural history studies in KD patients, we can only refer to a few retrospective surgical case reports. Therefore, we disagree that our surgical approach was an over-indication just because our patients were asymptomatic and had maximum diameters less than 50mm. Surgery has been indicated for fusiform aneurysms with maximum diameters >50mm, or saccular aneurysms, even if patients are asymptomatic. Our series included 6 fusiform aneurysms with maximum diameters >50mm and 3 saccular aneurysms <50mm. Consensus on surgical strategy requires a prospective study of KD patients with long-term follow-up. Nine of our cases did not have the usual laterality of the aortic arch. However, the distribution of the laterality of the aortic arch cannot be explained statistically. Further, we should accumulate worldwide data on KD patients, because only a few cases may be encountered in single institution. Funding

Immunoglobulin G4-related large thoraco-abdominal aortic aneurysm

We report a case of immunoglobulin G4-related large thoraco-abdominal aortic aneurysm in a 38-year old man. Preoperative contrast-enhanced computed tomography revealed that the mid-descending thoracic aorta was extremely enlarged and the maximum diameter of the aneurysm was 92 mm. The patient underwent thoraco-abdominal aortic replacement through a thoraco-abdominal incision under left heart bypass. The postoperative pathological examination diagnosed immunoglobulin G4-related aortic aneurysm.

Beveled reversed elephant trunk procedure for complex aortic aneurysm.

The reversed elephant trunk procedure uses an inverted graft for distal aortic replacement before aortic arch replacement in patients with mega aorta, to reduce the risk in the second stage. However, the conventional technique restricts the maximum diameter of the inverted graft to the aortic graft diameter. We employed a beveled reversed elephant trunk procedure to overcome the discrepancy between graft diameters in a 54-year-old woman with a severely twisted ascending aortic graft and enlarging chronic dissection of the aortic arch and descending thoracic aorta. The patient was discharged with a satisfactory repair and no neurologic deficit.