Variations and inequities in access to cardiac diagnostic services in Ontario Canada.

OBJECTIVES: Echocardiography is an essential diagnostic modality known to have wide regional utilization variations. This study's objectives were to quantify regional variations and to examine the extent to which they are explained by differences in population age, sex, cardiac disease prevalence (CDP), and social determinants of health (SDH) risk. METHODS: This is an observational study of all echocardiography exams performed in Ontario in 2019/20 (n = 695,622). We measured regional variations in echocardiography crude rates and progressively standardized rates for population age, sex, CDP, and SDH risk. RESULTS: After controlling for differences in population age, sex, and CDP, Ontario's highest rate regions had echocardiography rates 57% higher than its lowest rate regions. Forty eight percent of total variation was not explained by differences in age, sex, and CDP. CDP increased with SDH risk. Access to most cardiac diagnostics was negatively correlated with SDH risk, while cardiac catheterization rates were positively correlated with SDH risk. CONCLUSION: Variations analysis that adjusts for age and sex only without including clinical measures of need are likely to overestimate the unwarranted portion of total variation. Substantial variations persisted despite a mandatory provider accreditation policy aimed at curtailing them. The associations between variations and SDH risks imply a need to redress access and outcome inequities.

Chest Pain Evaluation: Diagnostic Testing.

Chest pain/discomfort (CP) is a common symptom and can be a diagnostic dilemma for many clinicians. The misdiagnosis of an acute or progressive chronic cardiac etiology may carry a significant risk of morbidity and mortality. This review summarizes the different options and modalities for establishing the diagnosis and severity of coronary artery disease. An effective test selection algorithm should be individually tailored to each patient to maximize diagnostic accuracy in a timely fashion, determine short- and long-term prognosis, and permit implementation of evidence-based treatments in a cost-effective manner. Through collaboration, a decision algorithm was developed (www.chowmd.ca/cadtesting) that could be adopted widely into clinical practice.

La douleur ou la gêne thoracique sont des symptômes fréquents qui peuvent poser un dilemme diagnostique pour de nombreux médecins. Les erreurs de diagnostic d'une cause aiguë ou chronique progressive d'origine cardiaque peuvent d'ailleurs entraîner un risque considérable de morbidité et de mortalité. La présente synthèse porte sur les différentes options et modalités d'établissement du diagnostic et de la gravité d'une coronaropathie. Un algorithme efficace pour le choix des tests doit être adapté à chaque patient afin de maximiser l'exactitude diagnostique dans les plus brefs délais, de déterminer le pronostic à court et à long terme, et de permettre une mise en œuvre de traitements fondés sur des données probantes tout en tenant compte des coûts. Un algorithme décisionnel a donc été conjointement mis au point (www.chowmd.ca/cadtesting) et pourrait être largement adopté dans la pratique clinique.

Impact of a Mandated Accreditation Process on 1,045 Registered Echocardiographic Service Providers in a Previously Unregulated, Publicly Funded Environment.

BACKGROUND: This review was undertaken to examine the impact of a standards-based, mandated accreditation process on several aspects of echocardiographic service delivery in a single-payer, previously unregulated environment. METHODS: In the province of Ontario, virtually all echocardiographic services are funded by the Ministry of Health and Long Term Care. The Echocardiography Quality Improvement (EQI) process was introduced in 2012 and subsequently linked formally to reimbursement in 2016. Previously, payment for echocardiographic services in Ontario was unregulated. The impact of EQI on the number of facilities, echocardiographic volumes, costs, quality standards, and physician service provision were compared before and after implementation. RESULTS: Of the initial 1,045 registrants, 604 (57.8%) have been accredited or accreditation is expected having successfully resolved identified deficiencies. The remaining registrants were either never functionally operating (323 [30.9%]) or have withdrawn services (118 [11.3%]) since mandatory registration became a requirement for reimbursement. A number of factors identified facilities that were able to most promptly meet EQI standards, including hospital-based, academic, and multiple-physician facilities. The average annual increase in the utilization of echocardiographic services before EQI was 6.7%, decreasing to 2.7% since. The proportion of repeat examinations decreased in community-based facilities. Since 2013, costs for echocardiographic services have totaled about $92.3 million less than predicted by pre-2012 trends. To address standards, some small, more isolated facilities sought out alliances with larger facilities, particularly those affiliated with academic hospitals. CONCLUSIONS: EQI is demonstrably a means for improving quality while reducing the rate of growth and repeat examinations.

Mitral chordal-leaflet-myocardial interactions in mitral valve prolapse.

BACKGROUND: The submitral apparatus maintains annular-papillary continuity and myocardial geometry. In mitral valve prolapse (MVP), elongated chords and redundant leaflets can interact at the region of myocardial attachment, leading to apparent discordant motion of the basal inferolateral wall. The aim of this study was to test the hypothesis that basal inferolateral wall inward motion would occur later in MVP and that this delay is associated with MVP severity. METHODS: Thirty consecutive patients with MVP and matched controls underwent stress echocardiography. Time to peak transverse displacement (TPD) of the inferolateral wall compared with the anteroseptal wall was measured using speckle-tracking echocardiography. The time difference was analyzed as raw data, normalized to the RR interval, and as a percentage of the time to maximal displacement of the anteroseptal segment(s). RESULTS: Compared with controls, TPD was delayed in patients with MVP both at rest and at peak stress, when evaluating basal segments or basal-mid segments as a unit, both in real time and, more importantly, when correcting for anteroseptal TPD. In patients compared with controls, observed delay at rest and at peak stress was 50 ± 90 versus -30 ± 90 msec (P = .006) and 70 ± 80 versus -30 ± 60 msec (P < .0001), respectively; relative to TPD of the anteroseptal segment, the observed delay at rest and at peak stress was 117 ± 24% versus 97 ± 22% (P = .007) and 144 ± 68% versus 95 ± 21% (P = .003), respectively. Similar significant findings were observed in basal-mid segments. TPD results were not statistically significant when stratified by prolapse severity. Intraclass correlation coefficients were 0.88 and 0.93, and two-tailed t tests indicated good interobserver and intraobserver variability. CONCLUSIONS: Inferolateral wall TPD is delayed in MVP. TPD is a novel method to characterize chordal-leaflet-myocardial interactions in patients with MVP. Prolapse severity does not predict TPD, likely because of the timing of prolapse and dynamic loading conditions. Implications of this observation include attribution of a perceived wall motion abnormality in MVP during stress echocardiography to a physiologic state and new mechanistic insights into mitral valve physiology.

Development and evaluation of methodologies for teaching focused cardiac ultrasound skills to medical students.

BACKGROUND: Handheld ultrasound is emerging as an important tool for point-of-care cardiac assessment. Although cardiac ultrasound skills are traditionally introduced during postgraduate training, the optimal time and methodology to initiate training in focused cardiac ultrasound (FCU) are unknown. The objective of this study was to develop and evaluate a novel curriculum for training medical students in the use of FCU. METHODS: The study was conducted in two phases. In the first phase, 12 first-year medical students underwent FCU training over an 8-week period. In the second phase, 45 third-year medical students were randomized to one of three educational programs. Program 1 consisted of a lecture-based approach with scan training by a sonographer. Program 2 coupled electronic education modules with sonographer scan training. Program 3 was fully self-directed, combining electronic modules with scan training on a high-fidelity ultrasound simulator. Image interpretation skills and scanning technique were evaluated after each program. RESULTS: First-year medical students were able to modestly improve interpretation ability and acquire limited scanning skills. Third-year medical students exhibited similar improvement in mean examination score for image interpretation whether a lecture-based program or electronic modules was used. Students in the self-directed group using an ultrasound simulator had significantly lower mean quality scores than students taught by sonographers. CONCLUSIONS: Third-year medical students were able to acquire FCU image acquisition and interpretation skills after a novel training program. Self-directed electronic modules are effective for teaching introductory FCU interpretation skills, while expert-guided training is important for developing scanning technique.

Standards for provision and accreditation of echocardiography in Ontario.

In March of 2010, the Ontario Ministry of Health and Long-term Care and Ontario Medical Association jointly commissioned a Working Group to make recommendations regarding the provision and accreditation of echocardiographic services in Ontario. That commission undertook a process to examine all aspects of the provision, reporting and interpretation of echocardiographic examinations, including the echocardiographic examination itself, facilities, equipment, reporting, indications, and qualifications of personnel involved in the acquisition and interpretation of studies. The result was development of a set of 54 performance standards and a process for accreditation of echocardiographic facilities, initially on a voluntary basis, but leading to a process of mandatory accreditation. This article, and its accompanying Supplemental Material, outline the mandate, process undertaken, standards developed, and accreditation process recommended.

A post-myectomy heart: 20 years later.

We present the case of a 20-year old male that underwent a surgical ventricular septal myectomy at 8 months of age for symptomatic and drug-refractory obstructive hypertrophic cardiomyopathy (HCM). Though he has remained asymptomatic since the operation, he now demonstrates findings of cardiac arrhythmia and left ventricular dysfunction. His case is of particular interest as it represents a detailed and lengthy follow-up from early childhood to adulthood. Recognizing the post-myectomy state as a potentially separate entity from non-operated HCM can promote an individualized approach to long-term medical management.

Primary cardiac diffuse large B cell lymphoma presenting with superior vena cava syndrome.

Primary cardiac lymphomas are rare extranodal lymphomas that should be distinguished from secondary cardiac involvement by disseminated non-Hodgkin's lymphoma. Cardiac lymphomas often mimic other cardiac neoplasms, including myxomas and angiosarcomas, and often require multimodality cardiac imaging, in combination with endomyocardial biopsy, excisional biopsy or pericardial fluid cytology, to establish a definitive diagnosis. A 60-year-old immunocompetent man who presented with superior vena cava syndrome secondary to a right atrial, primary cardiac diffuse large B cell lymphoma (non-Hodgkin's lymphoma) is described in the present article. The patient had no clinical evidence of disseminated lymphoma and was successfully treated with prompt surgical excision of his atrial mass, followed by anthracycline-based chemotherapy. The patient required multi-modality cardiac imaging to accurately identify and plan surgical excision of his cardiac lymphoma. The therapeutic management and clinical and radio-logical features of primary cardiac lymphoma are reviewed.

Effect of long-term aspirin use on embolic events in infective endocarditis.

BACKGROUND: In a recent clinical trial, aspirin therapy was initiated approximately 34 days after the onset of symptoms but did not reduce the risk of embolism in patients with endocarditis. However, it is possible that aspirin used early in the course of the disease may be beneficial. The purpose of the study is to assess the effect of long-term daily aspirin use on the risk of embolic events in patients with infective endocarditis. METHODS: The clinical characteristics and outcomes of patients excluded from the Multi-Centre Aspirin Trial in Infective Endocarditis because of long-term aspirin use (n = 84) were compared with the data for patients randomized to the placebo arm (n = 55). The former patients took aspirin before and during the early stages of infective endocarditis, whereas the latter patients were not exposed to aspirin before and during the entire hospitalization. Logistic modeling was used to assess the effect of long-term aspirin use on embolism and bleeding. RESULTS: There was a trend toward excess bleeding in long-term aspirin recipients, compared with placebo recipients (P = .065). Logistic modeling revealed that long-term aspirin use may be associated with excess bleeding (unadjusted odds ratio, 2.35 [P = .059]; adjusted odds ratio, 2.08 [P = .118]), but it had no impact on the risk of embolic events in either model. CONCLUSIONS: In patients with endocarditis, long-term daily use of aspirin does not reduce the risk of embolic events but may be associated with a higher risk of bleeding. In the acute phase of endocarditis, aspirin should be used with caution.

Guidelines for the provision of echocardiography in Canada: recommendations of a joint Canadian Cardiovascular Society/Canadian Society of Echocardiography Consensus Panel.

Recognizing the central role of echocardiographic examinations in the assessment of most cardiac disorders and the need to ensure the provision of these services in a highly reliable, timely, economical and safe manner, the Canadian Cardiovascular Society and Canadian Society of Echocardiography undertook a comprehensive review of all aspects influencing the provision of echocardiographic services in Canada. Five regional panels were established to develop preliminary recommendations in the five component areas, which included the echocardiographic examination, the echocardiographic laboratory and report, the physician, the sonographer and indications for examinations. Membership in the panels was structured to recognize the regional professional diversity of individuals involved in the provision of echocardiography. In addition, a focus group of cardiac sonograhers was recruited to review aspects of the document impacting on sonographer responsibilities and qualification. The document is intended to be used as a comprehensive and practical reference for all of those involved in the provision of echocardiography in Canada.

Stress echocardiography in the evaluation of women presenting with chest pain syndrome: a randomized, prospective comparison with electrocardiographic stress testing.

OBJECTIVE: To evaluate the relative value of three stress testing modalities for establishing the presence of coronary artery disease in women presenting with chest pain. BACKGROUND: Echocardiographic testing modalities have the potential to be more effective than standard electrocardiographic stress testing (EST), but they require prospective evaluation. METHODS: Patients with no cardiac history and at least two cardiac risk factors were randomly assigned to one of three initial diagnostic strategies: treadmill EST (n=54), treadmill echocardiographic stress testing (ExE) (n=57) or dobutamine stress echocardiography (DSE) (n=47). Patients were followed prospectively for 28.1+/-14.2 months. The nature of the presenting chest pain was established clinically. RESULTS: Twelve patients (7.6%) were determined to have had cardiac chest pain, 128 patients (81.0%) received a diagnosis of noncardiac chest pain and 18 patients (11.4%) had indeterminate results. The echocardiographic testing modalities were associated with fewer indeterminate results than was EST (two of 104 [1.9%] versus 13 of 54 [24.1%]). All modalities were highly effective in excluding cardiac chest pain, with negative predictive values of 91.3%, 83.7% and 88.4%, respectively, for EST, DSE and ExE. The proportion of cases for which both definitive and accurate results were provided was 92.9% for DSE, 82.4% for ExE and 67.3% for EST. CONCLUSIONS: The results support the favourable prognosis of women presenting with chest pain syndrome and the reliability of negative results obtained with any of the testing modalities. Echocardiographic testing modalities are more likely than EST to provide both definitive and accurate results and would, therefore, seem to be the superior primary noninvasive testing modality in this patient population.

Defining low risk for coronary heart disease among women with chest pain syndrome: a prospective evaluation.

BACKGROUND: A better understanding of the clinical manifestations of coronary disease in women may lead to earlier recognition and better outcomes. METHODS: One hundred fifty-eight women coming to primary care physicians, emergency rooms, or cardiology clinics with undefined chest pain and at least two risk factors underwent detailed clinical evaluation of risk factor profile and symptom characteristics as well as stress testing. The significance of the presenting symptoms was evaluated on the basis of clinical events during an average 26.2 months of follow-up. Noncardiac pain was diagnosed on the basis of spontaneous resolution of symptoms, establishment of an alternative diagnosis, or negative coronary angiography. Cardiac chest pain was established by the development of cardiac clinical events or angiographic demonstration of coronary disease. RESULTS: Noncardiac chest pain was established in 128 (81%) patients. The remaining 30 (19%) either were found to have had cardiac chest pain or remain symptomatic without definitive diagnosis. Multivariate analysis revealed that noncardiac chest pain was best predicted by a combination of nondiabetic status and negative stress testing. The clinical characteristics of the chest pain syndrome were not significant contributors. CONCLUSIONS: In nondiabetic women with chest pain syndrome and at least two other cardiac risk factors, a negative stress test predicts a benign course in over 2 years of follow-up.

A randomized trial of aspirin on the risk of embolic events in patients with infective endocarditis.

OBJECTIVES: This study examined the effect of aspirin on the risk of embolic events in infective endocarditis (IE). BACKGROUND: Embolism is a major complication of IE, and studies in animal models have shown that platelet inhibition with aspirin can lead to more rapid vegetation resolution and a lower rate of embolic events. METHODS: We conducted a randomized, double-blinded, placebo-controlled trial of aspirin treatment (325 mg/day) for four weeks in patients with IE to test the hypothesis that the addition of aspirin would reduce the incidence of clinical systemic embolic events. Patients with perivalvular abscess were excluded. Serial cerebral computed tomograms and transesophageal echocardiograms were obtained in a subset of patients. RESULTS: During the four-year study period, 115 patients were enrolled: 60 assigned to aspirin and 55 assigned to placebo. Embolic events occurred in 17 patients (28.3%) on aspirin and 11 patients (20.0%) on placebo, with an odds ratio (OR) of 1.62 (95% confidence interval [CI] 0.68 to 3.86, p = 0.29). There was a trend toward a higher incidence of bleeding in the patients taking aspirin versus placebo (OR 1.92, 95% CI 0.76 to 4.86, p = 0.075). Development of new intracranial lesions was similar in both groups. Aspirin had no effect on vegetation resolution and valvular dysfunction. CONCLUSIONS: In endocarditis patients already receiving antibiotic treatment, the addition of aspirin does not appear to reduce the risk of embolic events and is likely associated with an increased risk of bleeding. Aspirin is not indicated in the early management of patients with IE.