Machine learning derived echocardiographic image quality in patients with left ventricular systolic dysfunction: insights on the echo views of greatest image quality.

We sought to determine the cardiac ultrasound view of greatest quality using a machine learning (ML) approach on a cohort of transthoracic echocardiograms (TTE) with abnormal left ventricular (LV) systolic function. We utilize an ML model to determine the TTE view of highest quality when scanned by sonographers. A random sample of TTEs with reported LV dysfunction from 09/25/2017-01/15/2019 were downloaded from the regional database. Component video files were analyzed using ML models that jointly classified view and image quality. The model consisted of convolutional layers for extracting spatial features and Long Short-term Memory units to temporally aggregate the frame-wise spatial embeddings. We report the view-specific quality scores for each TTE. Pair-wise comparisons amongst views were performed with Wilcoxon signed-rank test. Of 1,145 TTEs analyzed by the ML model, 74.5% were from males and mean LV ejection fraction was 43.1 ± 9.9%. Maximum quality score was best for the apical 4 chamber (AP4) view (70.6 ± 13.9%, p<0.001 compared to all other views) and worst for the apical 2 chamber (AP2) view (60.4 ± 15.4%, p<0.001 for all views except parasternal short-axis view at mitral/papillary muscle level, PSAX M/PM). In TTEs scanned by professional sonographers, the view with greatest ML-derived quality was the AP4 view.

Incidence and Predictors of Adverse Events Among Initially Stable ST-Elevation Myocardial Infarction Patients Following Primary Percutaneous Coronary Intervention.

Background Cardiac intensive care units were originally created in the prerevascularization era for the early recognition of ventricular arrhythmias following a myocardial infarction. Many patients with stable ST-segment-elevation myocardial infarction (STEMI) are still routinely triaged to cardiac intensive care units after a primary percutaneous coronary intervention (pPCI), independent of clinical risk or the provision of critical care therapies. The aim of this study was to determine factors associated with in-hospital adverse events in a hemodynamically stable, postreperfusion population of patients with STEMI. Methods and Results Between April 2012 and November 2019, 2101 consecutive patients with STEMI who received pPCI in the Vancouver Coastal Health Authority were evaluated. Patients were stratified into those with and without subsequent adverse events, which were defined as cardiogenic shock, in-hospital cardiac arrest, stroke, re-infarction, and death. Multivariable logistic regression models were used to determine predictors of adverse events. After excluding patients presenting with cardiac arrest, cardiogenic shock, or heart failure, the final analysis cohort comprised 1770 stable patients with STEMI who had received pPCI. A total of 94 (5.3%) patients developed at least one adverse event: cardiogenic shock 55 (3.1%), in-hospital cardiac arrest 42 (2.4%), death 28 (1.6%), stroke 21 (1.2%), and re-infarction 5 (0.3%). Univariable predictors of adverse events were older age, female sex, prior stroke, chronic kidney disease, and atrial fibrillation. There was no significant difference in reperfusion times between those with and without adverse events. Following multivariable adjustment, moderate to severe chronic kidney disease (creatinine clearance <44 mL/min; 13% of cohort) was associated with adverse events (odds ratio 2.24 [95% CI, 1.12-4.48]) independent of reperfusion time, age, sex, smoking status, hypertension, diabetes, and prior myocardial infarction/PCI/coronary artery bypass grafting. Conclusions Only 1 in 20 initially stable patients with STEMI receiving pPCI developed an in-hospital adverse event. Moderate to severe chronic kidney disease independently predicted the risk of future adverse events. These results indicate that the majority of patients with STEMI who receive pPCI may not require routine admission to a cardiac intensive care unit following reperfusion.

Incidentally identified left ventricular apical aneurysm in a patient with Fabry disease.

Fabry disease is a rare X-linked lysosomal storage disorder caused by a deficiency in the lysosomal enzyme, galactosidase A, that can result in a progressive increase in the left ventricle (LV) wall thickness from glycosphingolipid deposition leading to myocardial fibrosis, conduction abnormalities, arrhythmias, and heart failure. We present a case of a patient with advanced Fabry cardiomyopathy, in whom a small LV apical aneurysm was incidentally discovered on abdominal imaging, which could have easily evaded detection on standard transthoracic echocardiography. The LV apex should be thoroughly interrogated in patients with Fabry cardiomyopathy, as the finding of LV aneurysm could have important management implications with respect to the prevention of stroke and sudden cardiac death.

The Cardiovascular System in Heat Stroke.

In June 2021, western Canada experienced an unprecedented heat wave, breaking dozens of temperature records. As a result, the region had a significant uptick in sudden deaths, emergency department visits, and hospital admissions. Under thermal stress, the human body achieves heat dissipation through evaporation of sweat and increased cutaneous blood flow. When these mechanisms are overwhelmed, the core body temperature rises, which leads to heat stroke, a life-threatening syndrome of hyperthermia and central nervous system dysfunction in the setting of an environmental thermal load. Heat dissipation relies on an intact cardiovascular system to dilate cutaneous vasculature and increase cardiac output. Individuals with impaired cardiovascular function have a limited ability to increase stroke volume, cardiac output, and blood flow to the skin, increasing the risk of heat stroke. In turn, these patients, whose cardiac condition is already compromised, are susceptible to cardiovascular complications of heat stroke, including arrhythmias, myocardial ischemia, heart failure, shock, and sudden death. Indeed, the majority of excess deaths during heat waves are cardiovascular in origin, highlighting the impact the cardiovascular system has on the development of heat stroke, and vice versa. This review summarizes the current understanding of the interaction between the cardiovascular system and heat stroke, including the pathophysiology, cardiovascular complications, and treatment.

En juin 2021, l'Ouest canadien a connu une vague de chaleur sans précédent, au cours de laquelle des dizaines de records de température ont été battus. La région a de ce fait connu une augmentation significative des morts subites, des consultations aux urgences et des hospitalisations. En cas de stress thermique, le corps humain dissipe la chaleur par l'évaporation de la sueur et l'augmentation du flux sanguin cutané. Lorsque ces mécanismes sont dépassés, la température corporelle centrale augmente ce qui entraîne un coup de chaleur, un syndrome potentiellement mortel associant une hyperthermie et une dysfonction du système nerveux central dans un contexte de charge thermique exogène. La dissipation de la chaleur repose sur la dilatation des vaisseaux sanguins cutanés et l'augmentation du débit cardiaque qui sont possibles lorsque le système cardiovasculaire est intact. Chez les personnes atteintes d'insuffisance cardiovasculaire, la capacité à augmenter le volume d'éjection, le débit cardiaque et le flux sanguin vers la peau est limitée, ce qui augmente le risque de coup de chaleur. Ainsi, ces patients dont la santé cardiaque est déjà compromise sont sensibles aux complications cardiovasculaires du coup de chaleur, dont les arythmies, l'ischémie myocardique, l'insuffisance cardiaque, l'état de choc et la mort subite. En effet, la surmortalité observée durant les vagues de chaleur est principalement d'origine cardiovasculaire, ce qui met en lumière l'effet du système cardiovasculaire sur la survenue des coups de chaleur, et vice versa. Le présent article résume la compréhension actuelle de l'interaction entre le système cardiovasculaire et le coup de chaleur, notamment pour ce qui est de la physiopathologie, des complications cardiovasculaires et des traitements.

Deliver Cardiac Virtual Care: A Primer for Cardiovascular Professionals in Canada.

The COVID-19 pandemic, with its need for distancing, has necessitated the use of virtual care in never-before-seen volumes. This review article aims to provide a primer on virtual care for cardiovascular professionals in Canada. The technology to facilitate remote patient interactions is already available, but barriers exist. Adequate and effective cardiac virtual care must be further developed given the need for rapid evaluation and close ongoing follow-up of patients, as seen in the areas of management of heart failure, cardiac rehabilitation, electrophysiology, and hypertension. Many Canadian organizations have published resources to assist health care providers and patients navigate the unfamiliar virtual care landscape. Although there are concerns surrounding issues such as patient privacy, access to technology, language discrepancies, and billing, these deficits provide opportunities for growth by health care organizations and technology companies. The integration of virtual care, home-based devices, and disruptive technologies emphasize the trend toward virtualization of health care, with the potential for greater personalization of health care interactions and continuity of care. Funding models were rapidly developed at the beginning of the COVID-19 pandemic, and although some provinces have deemed these changes as permanent, the status from other provinces remains unknown. The foundations to support virtual care as a key modality for health care delivery in Canada have been built, and further developments may strengthen its viability as a long-term option.

Dans le contexte de la pandémie de COVID-19 et de la distanciation sociale qu'elle impose, le recours aux soins de santé virtuels a atteint des sommets historiques. Le présent article de synthèse est une introduction aux soins de santé virtuels destinée aux professionnels de la santé cardiovasculaire du Canada. La technologie permettant de faciliter les interactions à distance avec les patients existe déjà, mais il y a des obstacles à sa mise en œuvre. Des soins de santé virtuels adéquats et efficaces doivent être développés davantage en cardiologie compte tenu de la nécessité d'une évaluation rapide et d'un suivi étroit et continu des patients, notamment quand il est question de prise en charge de l'insuffisance cardiaque, de réadaptation cardiaque, d'électrophysiologie ou d'hypertension. De nombreux organismes canadiens ont publié des ressources pour aider les fournisseurs de soins et les patients à trouver leurs repères dans l'univers peu connu des soins de santé virtuels. Les questions telles que la protection des renseignements personnels des patients, l'accès à la technologie, les différences linguistiques et la facturation soulèvent des préoccupations. Néanmoins, les lacunes constituent des possibilités de croissance pour les organismes de soins de santé et les entreprises technologiques. L'intégration des soins de santé virtuels, des dispositifs à domicile et des technologies perturbatrices met en lumière la tendance à la virtualisation des soins de santé, allant de pair avec la possibilité d'accroître la personnalisation des interactions et la continuité des soins. Des modèles de financement ont été rapidement élaborés au début de la pandémie de COVID-19. Bien que certaines provinces aient reconnu le caractère permanent des changements; la position des autres provinces demeure inconnue. Les conditions de base sont réunies pour que les soins de santé virtuels soient reconnus en tant que modalités clés de la prestation des soins de santé au Canada, et d'autres développements pourraient en renforcer la viabilité en tant qu'option à long terme.

Prevalence of left ventricular systolic dysfunction by single echocardiographic view: towards an evidence-based point of care cardiac ultrasound scanning protocol.

Limited views are often obtained in the setting of cardiac ultrasound, however, the likelihood of missing left ventricular (LV) dysfunction based on a single view is not known. We sought to determine the echo views that were least likely to miss LV systolic dysfunction in consecutive transthoracic echocardiograms (TTEs). Structured data from TTEs performed at 2 hospitals from September 25, 2017, to January 15, 2019, were screened. Studies of interest were those with reported LV dysfunction. Views evaluated were the parasternal long-axis (PLAX), parasternal-short axis at mitral (PSAX M), papillary muscle (PSAX PM), and apical (PSAX A) levels, apical 2 (AP2), apical 3 (AP3), and apical 4 (AP4) chamber views. The probability that a view contained at least 1 abnormal segment was determined and analyzed with McNemar's test for 21 adjusted pair-wise comparisons. There were 4102 TTE studies included for analysis. TTEs on males comprised 72.7% of studies with a mean LV ejection fraction of 42.8 ± 9.7%. The echo view with the greatest likelihood of encompassing an abnormal segment was the AP2 view with a prevalence of 93.4% (p < 0.001, compared to all other views). The PLAX view performed the worst with a prevalence of 82.5% (p < 0.015, compared to all other views). The best parasternal view for the detection of abnormality was the PSAX PM view at 90.4%. In conclusions, a single echo view will contain abnormal segments > 82% of the time in the setting of LV systolic dysfunction, with a prevalence of up to 93.4% in the apical windows.

Long COVID-19: A Primer for Cardiovascular Health Professionals, on Behalf of the CCS Rapid Response Team.

It is now widely recognized that COVID-19 illness can be associated with significant intermediate and potentially longer-term physical limitations. The term, "long COVID-19" is used to define any patient with persistent symptoms after acute COVID-19 infection (ie, after 4 weeks). It is postulated that cardiac injury might be linked to symptoms that persist after resolution of acute infection, as part of this syndrome. The Canadian Cardiovascular Society Rapid Response Team has generated this document to provide guidance to health care providers on the optimal management of patients with suspected cardiac complications of long COVID-19.

The Need for Telemedicine Integration Into Adult Cardiology Training Curricula in Canada.

COVID-19 brought telemedicine to the forefront of clinical cardiology. We aimed to examine the extent of trainees' involvement in and comfort with telemedicine practices in Canada with the use of a web-based self-administered survey. Eighty-six trainees from 12 training programs completed the survey (65% response rate). Results showed that before COVID-19, 39 trainees (45%) had telemedicine exposure, compared with 67 (78%) after COVID-19 (P < 0.001). However, only 44 trainees (51%) reported being comfortable or very comfortable with the use of telemedicine. Of the 67 trainees who were involved in telemedicine, 4 (6%) had full supervision during virtual visits, 13 (19%) had partial supervision, and 50 (75%) had minimal or no supervision. Importantly, 67 trainees (78%) expressed the need for telemedicine-specific training and 64 (74%) were willing to have their virtual visits recorded for the purpose of evaluation and feedback. Furthermore, 47 (55%) felt strongly or very strongly positive about incorporating telemedicine into their future practice. The main perceived barriers to telemedicine use were concerns about patients' engagement, fear of weakening the patient-physician relationship, and unfamiliarity with telemedicine technology. These barriers, together with training in virtual physical examination skills and medicolegal aspects of telemedicine, are addressed in several established internal medicine telemedicine curricula that could be adapted by cardiology programs. In conclusion, while the degree of telemedicine involvement since COVID-19 was high, the trainees' comfort level with telemedicine practice remains suboptimal likely due to lack of training and inadequate staff supervision. Therefore, a cardiology telemedicine curriculum is needed to ensure that trainees are equipped to embrace telemedicine in cardiovascular clinical care.

Cardiovascular Care Delivery During the Second Wave of COVID-19 in Canada.

Hospitals and ambulatory facilities significantly reduced cardiac care delivery in response to the first wave of the COVID-19 pandemic. The deferral of elective cardiovascular procedures led to a marked reduction in health care delivery with a significant impact on optimal cardiovascular care. International and Canadian data have reported dramatically increased wait times for diagnostic tests and cardiovascular procedures, as well as associated increased cardiovascular morbidity and mortality. In the wake of the demonstrated ability to rapidly create critical care and hospital ward capacity, we advocate a different approach during the second and possible subsequent COVID-19 pandemic waves. We suggest an approach, informed by local data and experience, that balances the need for an expected rise in demand for health care resources to ensure appropriate COVID-19 surge capacity with continued delivery of essential cardiovascular care. Incorporating cardiovascular care leaders into pandemic planning and operations will help health care systems minimise cardiac care delivery disruptions while maintaining critical care and hospital ward surge capacity and continuing measures to reduce transmission risk in health care settings. Specific recommendations targeting the main pillars of cardiovascular care are presented: ambulatory, inpatient, procedural, diagnostic, surgical, and rehabilitation.

Automated estimation of echocardiogram image quality in hospitalized patients.

We developed a machine learning model for efficient analysis of echocardiographic image quality in hospitalized patients. This study applied a machine learning model for automated transthoracic echo (TTE) image quality scoring in three inpatient groups. Our objectives were: (1) Assess the feasibility of a machine learning model for echo image quality analysis, (2) Establish the comprehensiveness of real-world TTE reporting by clinical group, and (3) Determine the relationship between machine learning image quality and comprehensiveness of TTE reporting. A machine learning model was developed and applied to TTEs from three matched cohorts for image quality of nine standard views. Case TTEs were comprehensive studies in mechanically ventilated patients between 01/01/2010 and 12/31/2015. For each case TTE, there were two matched spontaneously breathing controls (Control 1: Inpatients scanned in the lab and Control 2: Portable studies). We report the overall mean maximum and view specific quality scores for each TTE. The comprehensiveness of an echo report was calculated as the documented proportion of 12 standard parameters. An inverse probability weighted regression model was fit to determine the relationship between machine learning quality score and the completeness of a TTE report. 175 mechanically ventilated TTEs were included with 350 non-intubated samples (175 Control 1: Lab and 175 Control 2: Portable). In total, the machine learning model analyzed 14,086 echo video clips for quality. The overall accuracy of the model with regard to the expert ground truth for the view classification was 87.0%. The overall mean maximum quality score was lower for mechanically ventilated TTEs (0.55 [95% CI 0.54, 0.56]) versus 0.61 (95% CI 0.59, 0.62) for Control 1: Lab and 0.64 (95% CI 0.63, 0.66) for Control 2: Portable; p = 0.002. Furthermore, mechanically ventilated TTE reports were the least comprehensive, with fewer reported parameters. The regression model demonstrated the correlation of echo image quality and completeness of TTE reporting regardless of the clinical group. Mechanically ventilated TTEs were of inferior quality and clinical utility compared to spontaneously breathing controls and machine learning derived image quality correlates with completeness of TTE reporting regardless of the clinical group.

Impact of the updated diastolic function guidelines in the real world.

BACKGROUND: Echocardiographic assessment of diastolic function is complex but can aid in the diagnosis of heart failure, particularly in patients with preserved ejection fraction. In 2016, the American Society of Echocardiography (ASE) and European Association of Cardiovascular Imaging (EACVI) published an updated algorithm for the evaluation of diastolic function. The objective of our study was to assess its impact on diastolic function assessment in a real-world cohort of echo studies. METHODS: We retrospectively identified 71,727 consecutive transthoracic echo studies performed at a tertiary care center between February 2010 and March 2016 in which diastolic function was reported based on the 2009 ASE Guidelines. We then programmed a software algorithm to assess diastolic function in these echo studies according to the 2016 ASE/EACVI Guidelines. RESULTS: When diastolic function assessment based on the 2009 guidelines was compared to that using the 2016 guidelines, there were significant differences in proportion of studies classified as normal (23% vs. 32%) or indeterminate (43% vs. 36%) function, and mild (23% vs. 23%), moderate (10% vs. 8%), or severe (1% vs. 2%) diastolic dysfunction, with poor agreement between the two methods (Kappa 0.323, 95% CI 0.318-0.328). Furthermore, within the subgroup of studies with preserved ejection fraction and no evidence of myocardial disease, there was significant reclassification from mild diastolic dysfunction to normal diastolic function. CONCLUSION: The updated guidelines result in significant differences in diastolic function interpretation in the real world. Our findings have important implications for the identification of patients with or at risk for heart failure.

Guiding Cardiac Care During the COVID-19 Pandemic: How Ethics Shapes Our Health System Response.

The COVID-19 pandemic has raised ethical questions for the cardiovascular leader and practitioner. Attention has been redirected from a system that focuses on individual patient benefit toward one that focuses on protecting society as a whole. Challenging resource allocation questions highlight the need for a clearly articulated ethics framework that integrates principled decision making into how different cardiovascular care services are prioritized. A practical application of the principles of harm minimisation, fairness, proportionality, respect, reciprocity, flexibility, and procedural justice is provided, and a model for prioritisation of the restoration of cardiovascular services is outlined. The prioritisation model may be used to determine how and when cardiovascular services should be continued or restored. There should be a focus on an iterative and responsive approach to broader health care system needs, such as other disease groups and local outbreaks.

Cardiac Rehabilitation During the COVID-19 Era: Guidance on Implementing Virtual Care.

Cardiac rehabilitation programs across Canada have suspended in-person services as a result of large-scale physical distancing recommendations designed to flatten the COVID-19 pandemic curve. Virtual cardiac rehabilitation (VCR) offers an alternate mechanism of care delivery, capable of providing similar patient outcomes and safety profiles compared with centre-based programs. To minimize care gaps, all centres should consider developing and implementing a VCR program. The process of this rapid implementation, however, can be daunting. Centres should initially focus on the collation, utilization, and repurposing of existing resources, equipment, and technology. Once established, programs should then focus on ensuring that quality indicators are met and care processes are protocolized. This should be followed by the development of sustainable VCR solutions to account for care gaps that existed before COVID-19, and to improve cardiac rehabilitation delivery, moving forward. This article reviews the potential challenges and obstacles of this process and aims to provide pragmatic guidance to aid clinicians and administrators during this challenging time.