Darrin M. Payne

Infectious endocarditis of a Chiari network

We present the case of a 62-year-old man with infectious endocarditis in a Chiari network. Chiari networks are present in 1.5% to 3% of the population. Although Chiari networks are usually clinically insignificant, they are associated with a number of conditions, including patent foramen ovale, thromboembolism, atrial aneurysm, and cardiac arrhythmias. Although there are rare reports of patients with a Chiari network who had endocarditis develop, this is the first report of a patient who had endocarditis develop solely within a Chiari network.

Hemodynamic Performance of Stentless Versus Stented Valves: A Systematic Review and Meta-Analysis

Abstract  Background: Several trials have compared stentless with stented valves following aortic valve replacement (AVR). The goal of this review was to systematically locate, critically appraise, and quantitatively combine results to determine if stentless valves improve cardiac hemodynamics. Methods: We performed an unrestricted search of Pubmed Medline, EMBASE, CINAHL, the Cochrane databases, and EBM reviews. Article reference lists and online abstracts from major North American conferences were also searched. We included randomized trials of adults undergoing AVR that compared stentless and stented valves. Blinded reviewers performed assessment of trials for inclusion and trial quality. Two individuals performed data extraction independently. Kappa statistics were used to assess reviewer agreement. A random effects model was employed for statistical analyses. Assessments were made for postoperative, early, and late outcomes. Heterogeneity was explored with sensitivity analyses. Results: Eight studies were identified for inclusion in the primary analysis, with four others included in sensitivity analyses. Baseline comparisons between groups revealed no differences. Our primary analyses revealed no differences between groups for assessments of LV mass or mean transvalvar gradients. Secondary analyses showed stentless valves to have lower peak gradients. Sensitivity analyses were supportive of our primary results. Heterogeneity was observed in some comparisons and sensitivity analyses failed to completely explain this heterogeneity. Conclusions: Stentless valves did not display hemodynamic benefit in terms of LV mass regression or postoperative mean gradients, but do appear to display superior hemodynamics in terms of peak gradients. Further well‐designed and adequately powered trials are required to fully address this question.

Epidemiology and management of thoracic aortic dissections and thoracic aortic aneurysms in Ontario, Canada: A population-based study

Objectives: To determine hospital incidence, mortality, and management for thoracic aortic dissections and aneurysms. Methods: A population‐based retrospective cohort study of anonymously linked data for residents of Ontario, Canada, was carried out. Incident cases of thoracic aortic dissections and aneurysms were identified between 2002 and 2014. Treatment and mortality trends were assessed. Results: There were 5966 aortic dissections (Type A n = 2289 [38%] and Type B n = 3632 [61%]). Overall incidence proportion for aortic dissections was 4.6 per 100,000. There were 9392 thoracic aortic aneurysms with an overall incidence proportion of 7.6 per 100,000. The incidence for both dissections and aneurysms significantly increased over the 12‐year study. Only 53% (1204 out of 2289) of Type A dissections underwent surgery. Type B dissection treatment was 83% (3000 out of 3632) medical, 10% (370 out of 3632) surgery, and 7% (262 out of 3632) endovascular. Thoracic aortic aneurysm treatment was 53% (4940 out of 9392) surgery, 44% (4129 out of 9392) medical, and 3% (323 out of 9392) endovascular. Thirty‐five percent of known descending thoracic aortic aneurysms (323 out of 924) received a stent graft. Cardiac surgeons performed 87% of the open surgical repairs. Vascular surgeons performed 91% of the endovascular procedures. All‐cause 3‐year mortality significantly decreased for both aortic dissections (44% to 40%) and aneurysms (30% to 22%). All‐cause hospital mortality also decreased. Women had worse outcomes than men. Conclusions: The incidence of thoracic aortic dissections and aneurysms increased over time but all‐cause hospital and late outcomes improved. Gender differences exist. Men incur more disease but women have higher hospital mortality. Surgery was primarily referred to cardiac surgeons. Endovascular therapy was primarily referred to vascular surgeons.

Successful Management of Cold-Induced Urticaria During Hypothermic Circulatory Arrest

Cold-induced urticaria (CIU) is a potentially life-threatening immunologic disorder characterized by swelling and edema of exposed tissue in response to a cold stimulus. We describe the successful management of a patient with a history of severe CIU who required coronary bypass and repair of an ascending aortic aneurysm using hypothermic circulatory arrest.

Prominent Septal Hypertrophy: A Contra-Indication for Transapical Aortic Valve Implantation?

Abstract  We report a case of transapical aortic valve implantation in a patient with severe left ventricular hypertrophy. The valve was deployed but failed to attain stable seating because of a hypertrophied septal ridge encroaching on the landing zone. Moderate perivalvar insufficiency was also noted. A second valve was deployed in an attempt to achieve stable seating and correct the perivalvar leak. This was unsuccessful and the two‐valve complex embolized into the ascending aorta. The valves were moved and seated in the proximal descending thoracic aorta. The technical issues of transapical aortic valve implantation in patients with severe left ventricular hypertrophy are reviewed.

The histology of human right atrial tissue in patients with high-risk Obstructive Sleep Apnea and underlying cardiovascular disease: A pilot study

Background Obstructive Sleep Apnea (OSA) results in intermittent hypoxia leading to atrial remodeling, which, among other things, facilitates development of atrial fibrillation. While much data exists on the macrostructural changes in cardiac physiology induced by OSA, there is a lack of studies looking for histologic changes in human atrial tissue induced by OSA which might lead to the observed macrostructural changes. Methods A case control study was performed. Patients undergoing coronary artery bypass grafting (CABG) were evaluated for OSA and categorized as high-risk or low-risk. The right atrial tissue samples were obtained during CABG and both microscopic histological analysis and Sirius Red staining were performed. Results 18 patients undergoing CABG were included; 10 high-risk OSA and 8 low-risk OSA in evenly matched populations. No statistically significant difference between the two groups was observed in amount of myocytolysis (p = 0.181), nuclear hypertrophy (p = 0.671), myocardial inflammation (p = n/a), amyloid deposition (p = n/a), or presence of thrombi (p = n/a), as measured through routine H&E staining. As well, no statistically significant difference in interstitial and epicardial collagen was observed, as measured by Sirius Red staining (for total tissue: p = 0.619: for myocardium: p = 0.776). Conclusions In this pilot study there were no observable histological differences in human right atrial tissue from individuals at high- and low-risk for OSA. Further investigation would be required for more definitive results.

Intraoperative diagnosis of unroofed coronary sinus after aortic valve replacement.

A patient with combined aortic insufficiency and stenosis underwent aortic valve replacement. After weaning off cardiopulmonary bypass, a new shunt into the left atrium was noted that had not been apparent on multiple previous echocardiographs. Using an agitated saline test, we confirmed a shunt between the coronary sinus and left atrium. The assumption was made that there had been an iatrogenic fistula created with placement of the retrograde catheter; however, upon opening the left atrium it was realized that the patient had a previously undiagnosed, congenitally unroofed coronary sinus. It was repaired primarily and the patient had an uneventful recovery.

Remote Ischemic Preconditioning in High-risk Cardiovascular Surgery Patients: A Randomized-controlled Trial

Remote ischemic preconditioning (RIPC) may reduce biomarkers of ischemic injury after cardiovascular surgery. However, it is unclear whether RIPC has a positive impact on clinical outcomes. We performed a blinded, randomized controlled trial to determine if RIPC resulted in fewer adverse clinical outcomes after cardiac or vascular surgery. The intervention consisted of 3 cycles of RIPC on the upper limb for 5 minutes alternated with 5 minutes of rest. A sham intervention was performed on the control group. Patients were recruited who were undergoing (1) high-risk cardiac or vascular surgery or (2) cardiac or vascular surgery and were at high risk of ischemic complications. The primary end point was a composite outcome of mortality, myocardial infarction, stroke, renal failure, respiratory failure, and low cardiac output syndrome, and the secondary end points included the individual outcome parameters that made up this score, as well as troponin-I values. A total of 436 patients were randomized and analysis was performed on 215 patients in the control group and on 213 patients in the RIPC group. There were no differences in the composite outcome between the 2 groups (RIPC: 67 [32%] and control: 72 [34%], relative risk [0.94 {0.72-1.24}]) or in any of the individual components that made up the composite outcome. Additionally, we did not observe any differences between the groups in troponin-I values, the length of intensive care unit stay, or the total hospital stay. RIPC did not have a beneficial effect on clinical outcomes in patients who had cardiovascular surgery.

Management of supravalvar aortic stenosis and severely depressed left ventricular function in a neonate with Williams syndrome

We report an interesting case of a patient with Williams syndrome who presented with moderate supravalvar aortic stenosis and bilateral pulmonary artery stenosis at one week of age. The supravalvar aortic stenosis became severe by the age of one month with severe depression of left ventricular function. The patient had a difficult postoperative course, developed an acquired aortic arch hypoplasia and required multiple interventions during the first two months of life with an excellent outcome. The management of this difficult patient is discussed with focus on the importance of close follow-up, early diagnosis and early surgical intervention in improving the outcome in this difficult group of patients.

Atypical localization of a left atrial myxoma at the free edge of mitral valve

Myxomas represent more than 50% of benign cardiac neoplasm and are the most frequent cardiac tumors (1). Recent studies showed these neoplasms are commonly located in the left atrium (>90%), usually as a pedicled mass arising from the inter-atrial septum at the border of the fossa ovalis (2). Intra-cardiac masses should be differentiated as they could potentially represent a primary or secondary metastatic mass or endocarditis vegetations. We present a case of an exceedingly rare myxoma location, arising from the free-edge of the posterior mitral valve (MV) leaflet, which was incidentally identified in a 20-year-old female investigated for recent onset shortness of breath.