Surgical management of calcific valvular and coronary disease in a patient with alkaptonuria: a case report.

Background: Alkaptonuria is a rare metabolic disease that causes an increase in homogentisic acid (HGA) due to a lack of enzymatic activity. Commonly, accumulation of HGA presents with dark discoloration of skin and other tissues, also known as ochronosis. Additionally, alkaptonuria can result in other clinical manifestations, including arthritis and cardiac disease. This case highlights alkaptonuria-related cardiac disease and challenges that cardiac surgery teams may face when treating this patient population. Case summary: A 62-year-old male with a history of alkaptonuria, Hodgkin's lymphoma treated with chemoradiation, hypertension, and hyperlipidaemia originally presented with shortness of breath in the setting of known cardiac disease. Cardiac work-up demonstrated aortic stenosis, mitral stenosis, and multivessel coronary artery disease requiring aortic valve replacement, mitral valve replacement, and coronary artery bypass grafting. During the operation, significant discoloration of tissue was observed. This correlated with areas of severe calcification, which was noted throughout both valves. Extensive debridement was required prior to proceeding to valve replacements. Additionally, near-infrared spectroscopy failed to provide accurate measurements of cerebral oxygenation. Discussion: Alkaptonuria is correlated with cardiovascular disease, particularly valvular disease. Intraoperatively, these patients may exhibit noticeable discoloration and severe calcification of various tissues. Additionally, traditional infrared-based methods of cerebral oxygenation monitoring may not be reliable; however, other options of cerebral monitoring may be feasible. With proper pre-operative planning, however, patients with alkaptonuria may safely undergo cardiac surgery.

Novel mesh suture may resist bone cutting seen with wire-based sternal closures.

Objective: Sternal dehiscence is frequently associated with wire-based closures cutting through fragile bone, allowing sternal motion, separation, and infection. We investigated whether bone cutting could be limited by using a newly available mesh suture with improved force distribution. Methods: Five sternal models were closed using 8 interrupted single sternal wires, double sternal wires, braided poly(ethylene terephthalate) sutures, single-wrapped mesh sutures, or double-wrapped mesh sutures. To simulate chest-wall forces, closed sternal models were pulled apart using 1020 N of axial force applied incrementally. Double sternal wire and double-wrapped mesh suture were further compared by closing 3 new models with each material and subjecting these models to cyclic loading cycles, simulating breathing and coughing. Image analysis of needle hole size measured "bone cutting" by each closure material and sternal distraction as a function of force. Results: All models exhibited maximal separation at the xiphoid. During axial loading, needle hole size increased 7.2% in the double-wrapped mesh suture model and 9.2% in the double-wire model. Single-wrapped mesh suture, single wires, and braided poly(ethylene terephthalate) extended needle hole size by 6.7%, 47.0%, and 168.3% of original size, respectively. The double-wire model resisted sternal distraction best, separating 0.285 cm at the xiphoid. During cyclic loading, mesh suture exhibited significantly less bone cutting (P = .02) than double wire, with comparable levels of sternal separation (P = .07). Conclusions: Mesh suture may resist bone cutting seen in sternal wire closure in bone models with comparable distraction to currently used sternal closure methods.

Conformational changes during in vitro balloon fracture of internal aortic annuloplasty ring.

Objective: HAART 300 300 (BioStable Science and Engineering, Inc) aortic annuloplasty rings restore physiologic annular geometry during aortic valve repair. Transcatheter valve-in-ring implantation is appealing for recurrent valve dysfunction but may necessitate balloon fracture of downsized annuloplasty rings. We characterized the feasibility of ring fracture and changes in ring geometry preceding fracture. Methods: The 19-mm, 21-mm, and 23-mm HAART 300 annuloplasty rings were obtained, and 23-mm, 24-mm, 25-mm, and 26-mm valvuloplasty balloons were obtained. Under continuous fluoroscopy and video recording, a 23-mm balloon was inflated within a 19-mm ring at 1 atm/s until ring fracture or balloon failure occurred. If balloon failure occurred, experiments were sequentially repeated with 1-mm upsized balloons until ring fracture occurred or no larger-sized balloons were available. Results: Upon balloon inflation, all rings exhibited an irreversible conformational change from an elliptical, annular geometry to a circular shape with ring posts flaring outward. A 23-mm balloon burst at 21 atm without fracturing the 19-mm ring. The 24-mm balloon fractured the 19-mm ring at 15 atm. Likewise, a 24-mm balloon ruptured at 18 atm without fracturing the 21-mm annuloplasty ring. A 25-mm balloon fractured the 21-mm ring at 18 atm. Finally, a 26-mm balloon burst at 20 atm without fracturing a 23-mm annuloplasty ring, but it did elicit the confirmational changes described. All fractures occurred along the upslope of a ring post. The exposed metal frame was visible after the 21-mm ring fracture. Conclusions: Fracture of HAART 300 aortic annuloplasty rings is possible with an oversized, high-pressure balloon. However, the geometrical changes in the ring and subsequent rupture of its fabric covering may be obstacles to safe, in vivo ring fracture.

The Unfulfilled Need for Technical Skill Assessments Among Academic Cardiothoracic Surgeons.

Technical skill is a proven predictor of surgical outcomes, yet no platform exists for continual technical skill development following training. We aim to characterize the perceived need for feedback on technical skill among practicing thoracic surgeons. Under the Thoracic Education Cooperative Group, a panel of cardiothoracic surgeons and trainees developed and distributed an online survey for cardiothoracic surgery faculty in the Thoracic Surgery Directors Association database. The survey solicited demographics, perceived need for constructive feedback, barriers to sharing critiques, and preferences of desired peer reviewers. One hundred forty surgeons responded to our survey (response rate: 19.6% [140/713]). Most respondents had practiced for greater than 15 years (49.3%, 69/140). About 76.4% (107/140) of responders agreed or strongly agreed receiving feedback on their technical skills would help them improve, and 71.5% (100/140) desired individualized skills feedback. While 61.4% (86/140) of surgeons received meaningful technical skill feedback as attending surgeons, this was infrequent, with 63.3% (88/139) last receiving feedback over 12 months prior. Commonly cited barriers to sharing feedback included lack of common practice, time constraints, and hierarchical barriers. About 66.2% (92/139) of participants would spend at least 10 minutes providing peer feedback to receive feedback on their own skills, while 45.3% (63/139) would spend greater than 20 minutes. Attending thoracic surgeons identify an unmet desire for ongoing, constructive feedback on their technical skills following training. Surgeons feel critique fosters improvement and would devote significant time to engaging in peer feedback. A platform for exchange of technical skill feedback is warranted.

Double Aortic Arch With Kommerell Diverticulum.

BACKGROUND: Vascular rings with a Kommerell diverticulum (KD) most commonly occur in patients with a right aortic arch. We report on a less commonly seen subset of vascular ring patients-those with a double aortic arch and a KD. METHODS: Between 2002 and 2017, 66 patients underwent an operation for a double aortic arch. Ten of those patients also had excision of a KD. We performed a retrospective medical record review of these patients to characterize their demographics and outcomes. RESULTS: All 10 patients (7 male, 3 female) had a double aortic arch that was right dominant and also had a KD. The patients were a mean age of 4.9 ± 4.3 years (range, 6 months to 29 years), and median age was 4 years. All patients had preoperative computed tomographic angiography or magnetic resonance imaging and mean compression of the distal trachea of 63% ± 12% (range, 40% to 80%). The distal left arch was atretic in all patients. All patients underwent division of their left aortic arch, division of the ligamentum, and resection of the KD. The left subclavian artery was transferred to the left carotid artery in 2 patients. The mean size of the diverticulum was 9 × 10 mm. There were no major postoperative complications or readmissions. The postoperative length of stay was 3.1 ± 0.8 days. Five of the patients reported no related persisting symptoms. The remaining 5 patients reported substantial symptomatic relief with only minor respiratory symptoms. CONCLUSIONS: Vascular ring patients with a double aortic arch can also have a KD. In addition to dividing the smaller aortic arch and the ligamentum, we recommend excision of the KD.