Risk Factors for Postrepair Elevated Mitral Gradient: A Post-hoc Analysis of a Randomized Trial.

BACKGROUND: Predischarge elevated mean mitral gradients (>5 mm Hg) may occur after repair for degenerative mitral regurgitation. We sought to identify risk factors associated with elevated gradients and to evaluate its impact on functional outcomes at 12 months in this subanalysis of the Canadian Mitral Research Alliance CardioLink-2 trial. METHODS: One hundred four patients with degenerative mitral regurgitation undergoing mitral repair were randomized to either a leaflet resection or preservation strategy. Logistic regression was used to identify risk factors associated with an elevated gradient. Functional outcomes at 12 months were compared between participants with and without elevated gradients. RESULTS: Elevated gradients was identified in 15 participants (14.4%), which was not significantly different based on allocation to each repair strategy (P = .10). Patients with elevated gradients were more likely to be women (odds ratio [OR], 4.28; 95% confidence interval [CI], 1.29-14.19; P = .02) and to have a lower preoperative hemoglobin level (OR, 0.93; 95% CI, 0.89-0.98; P = .01) and smaller intercommissural diameter (OR, 0.86; 95% CI, 0.76-0.97; P = .02) and mitral annuloplasty size (OR, 0.71; 95% CI, 0.57-0.87; P = .001). The ratio of intercommissural diameter-to-annuloplasty size was similar between those with and without elevated gradients (both 0.8 ± 0.1, P = .69). At 12 months those with elevated gradients had a worse New York Heart Association functional status (P = .0001), lower peak oxygen saturation in exercise test (P = .01), smaller body weight-walk distance product (P = .02), and higher Borg scale (P = .01) in the 6-minute walk test. CONCLUSIONS: Female gender, smaller mitral anatomy sizes, and lower preoperative hemoglobin levels were associated with postoperative elevated mitral gradients, which was in turn were associated with reduced functional status. Further research is warranted to investigate these potential risk factors.

Leaflet Resection vs Preservation for Degenerative Mitral Regurgitation: Functional Outcomes and Mitral Stenosis at 12 Months in a Randomized Trial.

BACKGROUND: Mitral valve repair is the gold standard treatment for degenerative mitral regurgitation (MR). The Canadian Mitral Research Alliance (CAMRA) CardioLink-2 trial showed no significant association between repair strategy, that is, leaflet resection vs preservation, and risk of functional mitral stenosis. In this subanalysis, we compared outcomes and functional tests at 12 months. METHODS: CAMRA CardioLink-2 was a multicentre randomized controlled trial that allocated patients with degenerative MR and posterior leaflet prolapse to leaflet resection (n = 54) or preservation (n = 50). Stress echocardiography and functional status assessments, including the 6-minute walk test, were compared 12 months after repair. RESULTS: Baseline demographics, stress echocardiographic findings, and mitral annuloplasty prosthesis size (33.0 ± 3.0 vs 33.6 ± 3.4 mm; P = 0.4) were similar between the two groups. There were no readmissions for heart failure or deaths during the follow-up period. At 12 months, a larger percentage of patients were in NYHA functional class ≥ 2 in the resection group compared with the preservation group (P = 0.01). Exercise capacity, rate-pressure product, 6-minute walk distance, and mean mitral valve gradients were not significantly different between the groups at 12 months. A more prominent increase in mean mitral gradient with smaller annuloplasty sizes was observed in the resection group at both rest (P = 0.03) and peak exercise (P = 0.005) in the linear regression model. CONCLUSIONS: At 12 months, there were no significant differences in mitral valve gradient, exercise capacity, and 6-minute walk test between repair strategies. Leaflet preservation may offer a larger mitral valve orifice with improved gradients in patients requiring smaller annuloplasty sizes.

Empagliflozin Reduces Myocardial Extracellular Volume in Patients With Type 2 Diabetes and Coronary Artery Disease.

OBJECTIVES: This study sought to evaluate the effects of empagliflozin on extracellular volume (ECV) in individuals with type 2 diabetes mellitus (T2DM) and coronary artery disease (CAD). BACKGROUND: Empagliflozin has been shown to reduce left ventricular mass index (LVMi) in patients with T2DM and CAD. The effects on myocardial ECV are unknown. METHODS: This was a prespecified substudy of the EMPA-HEART (Effects of Empagliflozin on Cardiac Structure in Patients with Type 2 Diabetes) CardioLink-6 trial in which 97 participants were randomized to receive empagliflozin 10 mg daily or placebo for 6 months. Data from 74 participants were included: 39 from the empagliflozin group and 35 from the placebo group. The main outcome was change in left ventricular ECV from baseline to 6 months determined by cardiac magnetic resonance (CMR). Other outcomes included change in LVMi, indexed intracellular compartment volume (iICV) and indexed extracellular compartment volume (iECV), and the fibrosis biomarkers soluble suppressor of tumorgenicity (sST2) and matrix metalloproteinase (MMP)-2. RESULTS: Baseline ECV was elevated in the empagliflozin group (29.6 ± 4.6%) and placebo group (30.6 ± 4.8%). Six months of empagliflozin therapy reduced ECV compared with placebo (adjusted difference: -1.40%; 95% confidence interval [CI]: -2.60 to -0.14%; p = 0.03). Empagliflozin therapy reduced iECV (adjusted difference: -1.5 ml/m2; 95% CI: -2.6 to -0.5 ml/m2; p = 0.006), with a trend toward reduction in iICV (adjusted difference: -1.7 ml/m2; 95% CI: -3.8 to 0.3 ml/m2; p = 0.09). Empagliflozin had no impact on MMP-2 or sST2. CONCLUSIONS: In individuals with T2DM and CAD, 6 months of empagliflozin reduced ECV, iECV, and LVMi. No changes in MMP-2 and sST2 were seen. Further investigation into the mechanisms by which empagliflozin causes reverse remodeling is required. (Effects of Empagliflozin on Cardiac Structure in Patients With Type 2 Diabetes [EMPA-HEART]; NCT02998970).

Peripheral artery disease among Indigenous Canadians: What do we know?

Indigenous Canadians experience a disproportionate burden of chronic atherosclerotic diseases, including peripheral artery disease (PAD). Despite an estimated prevalence of 800 000 patients with PAD in Canada, the burden of the disease among Indigenous Canadians is unclear. Available evidence suggests that this population has a higher prevalence of several major risk factors associated with PAD (diabetes, smoking and kidney disease). Unique socioeconomic, geographic and systemic obstacles affecting Indigenous Canadians' health and health care access may worsen chronic disease outcomes. Little is known about the cardiovascular and limb outcomes of Indigenous peoples with PAD. A novel approach via multidisciplinary vascular health teams engaging Indigenous communities in a culturally competent manner may potentially provide optimal vascular care to this population. Further research into the prevalence and outcomes of PAD among Indigenous Canadians is necessary to define the problem and allow development of more ffective initiatives to alleviate the disease burden in this marginalized group.

Au Canada, les membres des communautés autochtones sont affectés de manière disproportionnée par les maladies athéroscléreuses chroniques, y compris par l'artériopathie périphérique (AP). Malgré une prévalence estimée de 800 000 patients atteints d'AP au Canada, on ignore quel est le fardeau de la maladie chez les membres des communautés autochtones. Selon les données accessibles, cette population présente une prévalence plus élevée de plusieurs facteurs de risque majeurs associé à l'AP (diabète, tabagisme et maladie rénale). Certains obstacles socioéconomiques, géographiques et systémiques particuliers nuisent aussi à leur santé et leur compliquent l'accès aux soins de santé, ce qui pourrait aggraver les répercussions des maladies chroniques. On en sait peu sur l'issue des problèmes cardiovasculaires et circulatoires périphériques chez les membres des communautés autochtones touchés par l'AP. Une approche nouvelle, impliquant les communautés concernées et offerte de manière culturellement compétente par des uipes de santé vasculaire multidisciplinaires, serait propice à la prestation de soins vasculaires optimaux. Il faudra approfondir la recherche sur la prévalence et l'issue de l'AP chez les membres des communautés autochtones pour cerner le problème et permettre la mise en place d'initiatives plus efficaces afin d'alléger le fardeau de la maladie dans ce groupe marginalisé.

Sutureless aortic valves: who is the right patient?

PURPOSE OF REVIEW: Sutureless aortic valve replacement (AVR) has emerged as an alternative to traditional AVR for patients with aortic stenosis who present a higher surgical risk, such as the elderly, or those with small or highly calcified aortic roots. With transcatheter aortic valve implantation - the other major AVR alternative - being used in increasingly lower-risk patients, the place of sutureless valves in the AVR landscape needs to be defined. In this review, we discuss recent data and expert opinion as it pertains to the subject of sutureless AVR. RECENT FINDINGS: Several recent studies have evaluated the performance of sutureless valves in a variety of clinical contexts, including minimally invasive operations and high-risk surgical procedures. The optimal surgical technique for sutureless AVR has been refined through the publication of several reports addressing technical considerations. Reduction in operative times represents the main advantage of sutureless valves over conventional surgical prostheses, and the possibility of complete annular decalcification - and hence a reduced incidence of paravalvular leak - is the primary advantage over TAVI. SUMMARY: Sutureless valves have emerged as an attractive option for high-risk patients or for complex surgeries where a minimization of bypass time is critical. However, there is limited data regarding long-term outcomes, durability or reoperation.

Dual antiplatelet therapy use by Canadian cardiac surgeons.

BACKGROUND: Dual antiplatelet therapy is the cornerstone treatment for patients with acute coronary syndrome. Recent Canadian Guidelines recommend the use of dual antiplatelet therapy for 1 year after coronary artery bypass grafting in patients with acute coronary syndrome, but considerable variability remains. METHODS: We performed a survey of 75 Canadian cardiac surgeons to assess the use of dual antiplatelet therapy. RESULTS: Whereas 58.6% of respondents indicated that the benefits of dual antiplatelet therapy were seen irrespective of how patients were managed after acute coronary syndrome, 36.2% believed that the benefits of dual antiplatelet therapy were limited to those treated medically or percutaneously. In regard to the timing of dual antiplatelet therapy administration, 57% of respondents indicated that dual antiplatelet therapy should be given upstream in the emergency department, whereas 36.2% responded that dual antiplatelet therapy should be given only once the coronary anatomy has been defined. The majority surveyed (81%) weighed bleeding risk as being more important than ischemic risk reduction. In stable patients after acute coronary syndrome, the majority of surgeons would wait approximately 4 days after the last dose of P2Y12 antagonist before coronary artery bypass grafting. Only 44.6% indicated that they routinely use dual antiplatelet therapy postrevascularization in the setting of acute coronary syndrome. Rather, most surgeons use dual antiplatelet therapy for select patients, such as those with a stented vessel without a bypass graft, endarterectomy, or off-pump coronary artery bypass grafting. CONCLUSIONS: Cardiac surgeons exhibit variation in their attitudes and practice patterns toward dual antiplatelet therapy after coronary artery bypass grafting, and in approximately half of cases, their practice does not adhere to current guideline recommendations. New trials focusing on coronary artery bypass grafting cases in their primary analysis and educational initiatives for surgeons that focus on guideline recommendations may be warranted.