Vascular Regenerative Cell Deficiencies in South Asian Adults.

BACKGROUND: South Asian individuals shoulder a disproportionate burden of cardiometabolic diseases. OBJECTIVES: The purpose of this study was to determine if vascular regenerative cell content varies significantly between South Asian and White European people. METHODS: Between January 2022 and January 2023, 60 South Asian and 60 White European adults with either documented cardiovascular disease or established diabetes with ≥1 other cardiovascular risk factor were prospectively enrolled. Vascular regenerative cell content in venous blood was enumerated using a flow cytometry assay that is based on high aldehyde dehydrogenase (ALDHhi) activity and cell surface marker phenotyping. The primary outcome was the difference in frequency of circulating ALDHhi progenitor cells, monocytes, and granulocytes between the 2 groups. RESULTS: Compared with White European participants, those of South Asian ethnicity were younger (69 ± 10 years vs 66 ± 9 years; P < 0.05), had lower weight (88 ± 19 kg vs 75 ± 13 kg; P < 0.001), and exhibited a greater prevalence of type 2 diabetes (62% vs 92%). South Asian individuals had markedly lower circulating frequencies of pro-angiogenic ALDHhiSSClowCD133+ progenitor cells (P < 0.001) and ALDHhiSSCmidCD14+CD163+ monocytes with vessel-reparative capacity (P < 0.001), as well as proportionally more ALDHhi progenitor cells with high reactive oxygen species content (P < 0.05). After correction for sex, age, body mass index, and glycated hemoglobin, South Asian ethnicity was independently associated with lower ALDHhiSSClowCD133+ cell count. CONCLUSIONS: South Asian people with cardiometabolic disease had less vascular regenerative and reparative cells suggesting compromised vessel repair capabilities that may contribute to the excess vascular risk in this population. (The Role of South Asian vs European Origins on Circulating Regenerative Cell Exhaustion [ORIGINS-RCE]; NCT05253521).

Temporal trends in mortality of aortic dissection and rupture in the UK, Japan, the USA and Canada.

OBJECTIVE: Aortic dissection and aortic aneurysm rupture are aortic emergencies and their clinical outcomes have improved over the past two decades; however, whether this has translated into lower mortality across countries remains an open question. The purpose of this study was to compare mortality trends from aortic dissection and rupture between the UK, Japan, the USA and Canada. METHODS: We analysed the WHO mortality database to determine trends in mortality from aortic dissection and rupture in four countries from 2000 to 2019. Age-standardised mortality rates per 100 000 persons were calculated, and annual percentage change was estimated using joinpoint regression. RESULTS: Age-standardised mortality rates per 100 000 persons from aortic dissection and rupture in 2019 were 1.04 and 1.80 in the UK, 2.66 and 1.16 in Japan, 0.76 and 0.52 in the USA, and 0.67 and 0.81 in Canada, respectively. There was significantly decreasing trends in age-standardised mortality from aortic rupture in all four countries and decreasing trends in age-standardised mortality from aortic dissection in the UK over the study period. There was significantly increasing trends in mortality from aortic dissection in Japan over the study period. Joinpoint regression identified significant changes in the aortic dissection trends from decreasing to increasing in the USA from 2010 and Canada from 2012. In sensitivity analyses stratified by sex, similar trends were observed. CONCLUSIONS: Trends in mortality from aortic rupture are decreasing; however, mortality from aortic dissection is increasing in Japan, the USA and Canada. Further study to explain these trends is warranted.

Race and Ethnicity in Cardiac Surgery: A Missed Opportunity?

BACKGROUND: Patients' race and/or ethnicity are increasingly being associated with differential surgical access and outcomes in cardiac surgery. However, deriving evidence-based conclusions that can inform surgical care has been difficult because of poor diversity in study populations and conflicting research methodology and findings. Using a fictional patient example, this review identifies areas of concern in research engagement, methodology, and analyses, as well as potential steps to improve race and ethnicity considerations in cardiac surgical research. METHODS: A narrative literature review was performed using the PubMed/MEDLINE and Google Scholar databases, with a combination of cardiac surgery, race, ethnicity, and disparities keywords. RESULTS: Less than half of the published cardiac surgery randomized control trials report the race and/or ethnicity of research participants. Racial and/or ethnic minorities make up <20% of most study populations and are significantly underrepresented relative to their proportions of the general population. Further, race and/or ethnicity of research participants is variably categorized based on ancestry, geographic regions, cultural similarities, or minority status. There is growing consideration of analyzing interrelated and confounding variables, such as socioeconomic status, geographic location, or hospital quality, to better elucidate racial and/or ethnic disparities; however, intersectionality considerations remain limited in cardiac surgery research. CONCLUSIONS: Racial and/or ethnic disparities are increasingly being reported in research engagement, cardiac pathologies, and surgical outcomes. To promote equitable surgical care, tangible efforts are needed to recruit racially and/or ethnically minoritized patients to research studies, be transparent and consistent in their groupings, and elucidate the impact of their intersectional social identities.

2023 Update on equity, diversity, and inclusion in Canadian cardiac surgery.

PURPOSE OF REVIEW: Despite efforts to diversify the medical field, cardiac surgery remains amongst the least diverse specialties. Specifically, the percentage of women and racial minorities has remained low in past few decades. This may impact prospective trainee recruitment and surgical care. This paper highlights recent efforts that aim to promote diversity and inclusion of the Canadian cardiac surgical workforce. RECENT FINDINGS: Formal programs have been established to support students at different stages of training. In 2022, the Canadian Society for Cardiac Surgery has released an equity, diversity, and inclusion statement to summarize the current state and the strategic goals to accomplish a more just working environment. At the local level, the University of Toronto Next Surgeon high school pilot program, provided low-income, women, and racial minority students mentorship and experiential exposure to our field. Also, the University of Toronto, scholarships funded summer research with cardiac surgeons for women, as well as Black and Indigenous medical students. SUMMARY: Tangible efforts that target high school, undergraduate, and medical students are underway to promote equity and diversity of cardiac surgeons in Canada. Future studies that evaluate the gaps and identify bottlenecks could better guide interventions at institutions across the country.

Wellness and burnout in cardiac surgery: not black and white.

PURPOSE OF REVIEW: Despite a growing emphasis on burnout in medicine, there remains a paucity of data in cardiac surgery. Herein, we summarize recent data on cardiac surgeon well being and identify factors for consideration in future burnout inquiries and management. RECENT FINDINGS: Overall, 70-90% of cardiothoracic surgeons report job satisfaction in the United States. However, 35-60% still endorse burnout symptoms, and the specialty reports some of the highest rates of depression (35-40%) and suicidal ideation (7%). Such negative experiences are greater among early-stage and female surgeons and may be addressed through targeted, program-specific wellness policies. Canada's single-payer healthcare system might exacerbate surgeon burnout due to lower financial compensation and job autonomy. SUMMARY: Cardiothoracic surgeons appear simultaneously burnt out and professionally fulfilled. They report a high incidence of depression and clock in the most hours, yet the majority would choose this specialty again. These findings reveal a more nuanced state of well being than previously appreciated and speak to ambiguities in how burnout is conceived and measured. A broader examination across surgical and social contexts highlights the hierarchical nature of burnout factors and potential ways forward. Collectively, these insights can inform assessments of burnout in Canadian cardiac surgery that remain absent to date.

Wearable Cardiac Rhythm Monitoring Device for Detection of Postoperative Atrial Fibrillation.

PURPOSE: This study evaluated the use of a wearable, patch-based cardiac rhythm monitoring device in detecting postoperative atrial fibrillation (POAF) among cardiac surgical patients within 30 days after hospital discharge. DESCRIPTION: From the SEARCH-AF (The Post-Surgical Enhanced Monitoring for Cardiac Arrhythmias and Atrial Fibrillation) CardioLink-1 trial, this study examined rates of POAF according to surgery type and the incremental value of continuous cardiac rhythm monitoring among patients who underwent valve surgery. The primary outcome was cumulative atrial fibrillation or atrial flutter lasting for ≥6 minutes detected by continuous monitoring or atrial fibrillation or atrial flutter documented by a 12-lead electrocardiogram within 30 days of randomization. EVALUATION: The primary outcome occurred in 8.2%, 13.5%, and 21.2% of patients who underwent isolated coronary artery bypass grafting (CABG), isolated valve surgery, and combined CABG and valve surgery. Relative to patients who underwent isolated CABG, those patients who had valve surgery were more likely to experience POAF. A higher diagnostic yield was obtained when the patch-based cardiac rhythm monitor was applied in patients who underwent valve surgery. CONCLUSIONS: Use of a wearable, patch-based cardiac monitoring device was an effective detection strategy among patients undergoing valve surgery, given their higher risk of developing POAF.

High sensitivity troponin-I threshold to predict perioperative myocardial infarction.

BACKGROUND: High-sensitivity Troponin I (hs-cTnI) has largely replaced conventional troponin assays in an effort to improve detection of myocardial infarction. However, the mean displacement of hs-cTnI following coronary artery bypass graft (CABG) and the optimal threshold to detect perioperative myocardial infarction (MI) is unclear. Our objective is to describe mean hs-cTnI values at 6-12 h post-CABG and to determine the highest specificity while maintaining 100% sensitivity hs-cTnI cut-off values for diagnosis of perioperative or type-5 MI. METHODS: Between 2016 and 2018, 374 patients underwent non-emergent, isolated CABG. Pre-operative and 6 h post-operative hs-cTnI values were recorded as well as ECG, echocardiographic and angiographic data. RESULTS: Of 374 patients, 151 (40.3%) had normal and 224 (59.7%) had elevated preoperative hs-cTnI. Patients with normal preoperative hs-cTnI had a mean 6 h hs-cTnI of 9193 ng/l or 270X the upper normal value. Eleven patients (7.3%) presented with post-operative MI with a mean 6 h hs-cTnI of 50,218 ng/l or 1477X the upper normal value. Patients with elevated preoperative hs-cTnI had a mean 6 h hs-cTnI of 9449 ng/l or 292X the upper normal value. Eleven patients (4.9%) who presented with post-operative MI had a mean 6 h hs-cTnI of 26,823 ng/l or 789X the upper normal value. CONCLUSIONS: We suggest hs-cTnI threshold of 80-fold in patients with normal pre-operative hs-cTnI and 2.7-fold in patients with elevated pre-operative hs-cTnI. These results have important implications for perioperative care and for surgical trial reporting.

Mortality trends of aortic stenosis in high-income countries from 2000 to 2020.

OBJECTIVE: The purpose of this study is to describe recent mortality trends from aortic stenosis (AS) among eight high-income countries. METHODS: We analysed the WHO mortality database to determine trends in mortality from AS in the UK, Germany, France, Italy, Japan, Australia, the USA and Canada from 2000 to 2020. Crude and age-standardised mortality rates per 100 000 persons were calculated. We calculated age-specific mortality rates in three groups (<64, 65-79 and ≥80 years). Annual percentage change was analysed using joinpoint regression. RESULTS: During the observation period, the crude mortality rates per 100 000 persons increased in all the eight countries (from 3.47 to 5.87 in the UK, from 2.98 to 8.93 in Germany, from 3.84 to 5.52 in France, from 1.97 to 4.33 in Italy, from 1.12 to 5.49 in Japan, from 2.14 to 3.38 in Australia, from 3.58 to 4.22 in the USA and from 2.12 to 5.00 in Canada). In joinpoint regression of age-standardised mortality rates, trend changes towards a decrease were observed in Germany after 2012 (-1.2%, p=0.015), Australia after 2011 (-1.9%, p=0.005) and the USA after 2014 (-3.1%, p<0.001). Age-specific mortality rates in age group ≥80 years had shifts towards decreasing trends in all the eight countries in contrast to other younger age groups. CONCLUSIONS: While crude mortality rates increased in the eight countries, shifts towards decreasing trends were identified in age-standardised mortality rates in three countries and in the elderly aged ≥80 years in the eight countries. Further multidimensional observation is warranted to clarify the mortality trends.

The Impact of Statins on Postdischarge Atrial Fibrillation After Cardiac Surgery: Secondary Analysis from a Randomized Trial.

Background: Whether statins reliably reduce the risk of postoperative atrial fibrillation (POAF) in patients undergoing cardiac surgery remains controversial. We sought to determine the impact of statin use on new-onset postdischarge POAF in the Post-Surgical Enhanced Monitoring for Cardiac Arrhythmias and Atrial Fibrillation (SEARCH-AF) CardioLink-1 randomized controlled trial. Methods: We randomized 336 patients with risk factors for stroke (CHA2DS2-VASc score ≥ 2) and no history of preoperative atrial fibrillation (AF) to 30-day continuous cardiac rhythm monitoring after discharge from cardiac surgery with a wearable, patched-based device or to usual care. The primary endpoint was the occurrence of cumulative AF and/or atrial flutter lasting for ≥ 6 minutes detected by continuous monitoring, or AF and/or atrial flutter documented by a 12-lead electrocardiogram within 30 days of randomization. Results: The 260 patients (77.4%) discharged on statins were more likely to be male (P = 0.018) and to have lower CHA2DS2-VASc scores (P = 0.011). Patients treated with statins at discharge had a 2-fold lower rate of POAF than those who were not treated with statins in the entire cohort (18.4% vs 8.1%, log-rank P = 0.0076). On multivariable Cox regression including the CHA2DS2-VASc score adjustment, statin use was associated with a lower risk of POAF (hazard ratio 0.43, 95% confidence interval: 0.25-0.98, P = 0.043). Use of statins at a higher intensity was associated with lower risk of POAF, suggestive of a dose-response effect (log-rank P trend = 0.0082). Conclusions: The use of statins was associated with a reduction in postdischarge POAF risk among patients undergoing cardiac surgery. The routine use of high-intensity statin to prevent subacute POAF after discharge deserves further study.

Contexte: L'efficacité des statines dans la réduction du risque de fibrillation auriculaire postopératoire (FAPO) chez les patients ayant subi une chirurgie cardiaque ne fait pas l'unanimité. Nous avons tenté de déterminer l'effet de l'utilisation des statines sur la survenue d'une FAPO inaugurale consécutive au congé de l'hôpital dans l'essai SEARCH-AF CardioLink-1, un essai contrôlé à répartition aléatoire sur le suivi étroit en postopératoire des arythmies cardiaques et de la fibrillation auriculaire. Méthodologie: Nous avons réparti aléatoirement 336 patients présentant des facteurs de risque d'AVC (score CHA2DS2-VASc ≥ 2) sans antécédents de fibrillation auriculaire (FA) préopératoire dans deux groupes : les patients du premier groupe étaient équipés d'un dispositif portable sous forme de timbre pour la surveillance continue du rythme cardiaque pendant 30 jours après la sortie de l'hôpital suivant une chirurgie cardiaque; les patients du second groupe étaient suivis de façon conventionnelle. Le critère d'évaluation principal était la survenue cumulative de FA et/ou de flutter auriculaire durant ≥ 6 minutes détecté par la surveillance continue, ou la FA et/ou le flutter auriculaire confirmé par un électrocardiogramme à 12 dérivations dans les 30 jours suivant la répartition aléatoire. Résultats: Les 260 patients (77,4 %) prenant des statines à leur congé de l'hôpital étaient plus susceptibles d'être des hommes (p = 0,018) et d'avoir un score CHA2DS2-VASc plus faible (p = 0,011). Les patients traités par des statines à leur congé de l'hôpital avaient deux fois moins de risques de présenter une FAPO que les patients ne recevant pas de statines dans l'ensemble de la cohorte (18,4 % contre 8,1 %, valeur de p calculée selon le test de Mantel-Haenszel = 0,0076). Dans une régression de Cox multivariable incluant l'ajustement du score CHA2DS2-VASc, l'utilisation des statines a été associée à un risque moindre de FAPO (rapport des risques instantanés : 0,43, intervalle de confiance à 95 % de 0,25 à 0,98; p = 0,043). L'utilisation de statines à plus fortes doses a été associée à un risque moindre de FAPO, ce qui laisse croire à un effet dose-réponse (valeur de p de tendance selon le test de Mantel-Haenszel = 0,0082). Conclusions: L'utilisation de statines est associée à une réduction du risque de FAPO après le congé de l'hôpital chez les patients ayant subi une chirurgie cardiaque. L'utilisation systématique de statines à fortes doses pour prévenir la FAPO subaiguë après le congé d'hôpital mérite une étude plus approfondie.

Age period cohort analysis of rheumatic heart disease in high-income countries.

INTRODUCTION: Rheumatic heart disease is considered well-controlled in high-income countries; however, its actual trends in mortality remain unclarified. We analyzed trends in mortality from rheumatic heart disease in association with age, period, and birth cohort. METHODS: We analyzed the WHO mortality database to determine trends in mortality from rheumatic heart disease in the UK, Germany, France, Italy, Japan, Australia, USA, and Canada from 2000 to 2020. We used age-cohort-period modeling to estimate cohort and period effects. Net drift (overall annual percentage change), local drift (annual percentage change in each age group) and heterogeneity were calculated. RESULTS: In the most recent year, crude mortality rates and age-standardized mortality rates ranged from 1.10 in the USA to 6.17 in Germany, and 0.32 (95% CI 0.31-0.34) in Japan and 1.70 (95% CI 1.65-1.75) in Germany, respectively. During the observation period, while Germany had a constant trend in overall annual percentage change, all the other countries had significant decreasing trends (p < 0.0001, respectively). Annual percent change was not homogeneous across each group in all 8 countries (pheterogeneity < 0.0001), with 2 peaks in the younger and older age categories. In Germany, Italy, Australia, and Canada, we found increasing mortality rates among older patients. Improving period and cohort risks for rheumatic heart disease mortality were generally observed, excluding Germany where the period effect was worsening and the cohort effect was constant. CONCLUSIONS: Mortality trends from rheumatic heart disease were decreasing in the study high-income countries except for Germany where higher mortality and two peaks in annual percentage change in younger and older age groups warrant further investigation.

Combined Minimally Invasive Surgical and Percutaneous Catheter Ablation of Atrial Fibrillation: JACC Review Topic of the Week.

Hybrid ablation is a novel therapy in the invasive management of patients with atrial fibrillation (AF) which combines minimally invasive surgical and percutaneous catheter-based techniques. The evidence is mainly based on observational studies from experienced centers, with success rates of approximately 70% and risks that are 2.0-fold to 3.6-fold higher than catheter-based ablation. Hybrid ablation is offered typically to patients with persistent or longstanding persistent AF which, by design, requires 2 procedures (epicardial surgical and endocardial catheter-based ablation). One randomized trial demonstrated that hybrid ablation was more effective than catheter-based ablation, but with higher complication rates. The incidence of the most serious complications has decreased in contemporary studies of hybrid ablation. At present, hybrid ablation should be performed by experienced centers on selected patients with persistent or longstanding persistent AF. Additional randomized trials are needed to define the risks, benefits, and cost effectiveness of hybrid ablation to identify its most appropriate application in clinical practice.

Predictors of mitral valve haemodynamics after mitral valve repair for degenerative mitral regurgitation.

OBJECTIVE: Intraoperative predictors of functional mitral valve (MV) stenosis after surgical repair of mitral regurgitation (MR) caused by prolapse remain poorly characterised. This study evaluated the effect of annuloplasty size on postoperative MV haemodynamics during exercise and evaluated predictors of MV hemodynamics. METHODS: 104 patients were randomly assigned to leaflet resection or preservation for surgical repair of MR in the Canadian Mitral Research Alliance CardioLink-2 study. In this post hoc analysis, we compared MV haemodynamics between the two surgical groups and examined the relationship between annuloplasty size and MV haemodynamics 1 year after repair in the combined groups. Echocardiograms were performed at baseline and intraoperatively. Exercise transthoracic echocardiography was performed 1 year postoperatively. Multivariable linear regression analysis was used to identify predictors of exercise MV gradients at follow-up. RESULTS: Mean age of participants was 65±10 years, and 83% were male. Median annuloplasty size was 34 (IQR 32-36). Dividing by the median, 48 (46%) had annuloplasty size of <34 mm and 56 (54%) had ≥34 mm. Mean and peak exercise gradients at 1 year were 11±5 mm Hg and 22±9 mm Hg in <34, and 6±3 mm Hg and 14±5 mm Hg in ≥34 (p<0.001). Rate of residual MR was similar in both groups. In multivariable analyses, annuloplasty size of ≥34 mm was associated with lower mean and peak exercise gradients at 12 months, after adjustment for repair type, age, sex, heart rate and body surface area (ß -4.1, 95% CI -6 to -3, p<0.001, and ß -7 95% CI -10 to -4, p<0.001, respectively). Intraoperative mean and peak MV gradients by transesophageal echocardiography independently predicted mean and peak resting and exercise gradients at follow-up (p<0.001). Similar results were obtained in both leaflet resection and preservation. CONCLUSION: Annuloplasty size of ≥34 mm is associated with a 4 and 7 mm Hg reduction in mean and peak exercise MV gradients, respectively, 1 year post MV repair regardless of the repair strategy used. Intraoperative TEE MV gradients predict exercise MV gradients 1 year post repair. TRIAL REGISTRATION NUMBER: NCT02552771.

Engaging medical students in cardiac surgery: a focus on equity, diversity, and inclusion.

PURPOSE OF REVIEW: The Coronavirus Disease 2019 pandemic prohibited Canadian medical students from in-person observerships. This may be particularly detrimental to under-represented groups that may consider surgical subspecialties. To address the unprecedented need for alternative surgical career exploration and diversity within the profession, The University of Toronto Cardiac Surgery Interest Group and Division of Cardiac Surgery collaborated on virtual experiential programming. RECENT FINDINGS: Medical students were invited to virtual (1) observerships of a cardiac bypass case, (2) mentorship sessions with surgeons, (3) resident teaching sessions, (4) multidisciplinary case-based Heart Team discussions to further their understanding of the scope of Cardiac surgery, and (5) a virtual coronary anastomosis training program. Additionally, a comprehensive virtual program was spearheaded to increase interest in Cardiac surgery among low-income Black high school students. SUMMARY: Trainee response to the virtual education, mentorship, and skill acquisition was positive. Trainees reported high levels of interest in the profession, particularly among females and under-represented minorities, supporting the principles of equity diversity, and inclusion in Cardiac surgery.

Generalizability of the REDUCE-IT trial to South Asians with cardiovascular disease.

BACKGROUND: South Asians (SAs) represent ∼25% of the world's population and account for >50% of global cardiovascular (CV) deaths, yet they continue to be underrepresented in contemporary clinical trials. The REDUCE-IT study demonstrated in a high-risk and predominantly White population that icosapent ethyl (IPE) lowered major adverse cardiovascular events by 25%. We sought to determine the generalizability of these results to a high-risk population of SAs with established CV disease living in Canada. METHODS: This was a cross-sectional observational study of 200 statin-treated SAs (≥45 years) with atherosclerotic CV disease (ASCVD) (NCT05271591). SA ethnicity was self-identified as being of Anglo-Indian, Bangladeshi, Bengali, Bhutanese, Goan, Gujarati, Indian, Jatt, Kashmiri, Maharashtrian, Malayali, Nepali, Pakistani, Punjabi, Sindhi, Sinhalese, Sri Lankan, Tamil, Telugu, or other SA. ASCVD was defined as the presence of coronary, carotid, or peripheral atherosclerosis. FINDINGS: Mean age of the cohort was 67 years, where 82% were men and 57% had diabetes. The predominant ASCVD phenotype was coronary artery disease (94%). Mean (SD) baseline LDL-C and triglycerides were 1.70 (0.8) mmol/L and 1.42 (1.0) mmol/L, respectively. Three-quarters were on high-intensity statin therapy. According to the Health Canada/Canadian Cardiovascular Society Guidelines and FDA-approved indication, 33% and 25% of the participants were, respectively, eligible for IPE. CONCLUSIONS: A large proportion of high-intensity, statin-treated, high-risk patients with ASCVD and of self-reported SA ethnicity are eligible for IPE. These data have important translational implications for SAs who are at a disproportionately higher risk of CV morbidity and mortality. FUNDING: This study was funded by an unrestricted grant provided by HLS Therapeutics Inc, Canada.