Adult Congenital Heart Disease Care in Canada: Has Quality of Care Improved in the Last Decade?

BACKGROUND

Patients with adult congenital heart disease (ACHD) are at increased risk of comorbidity and death compared with the age-matched population. Specialized care is shown to improve survival. The purpose of this study was to analyze current measures of quality of care in Canada compared with those published by our group in 2012.

METHODS

A survey focusing on structure and process measures of care quality in 2020 was sent to 15 ACHD centres registered with the Canadian Adult Congenital Heart Network. For each domain of quality, comparisons were made with those published in 2012.

RESULTS

In Canada, 36,708 patients with ACHD received specialized care between 2019 and 2020. Ninety-five cardiologists were affiliated with ACHD centres. The median number of patients per ACHD clinic was 2000 (interquartile range [IQR]: 1050, 2875). Compared with the 2012 results, this represents a 68% increase in patients with ACHD but only a 19% increase in ACHD cardiologists. Compared with 2012, all procedural volumes increased with cardiac surgeries, increasing by 12% and percutaneous intervention by 22%. Wait time for nonurgent consults and interventions all exceeded national recommendations by an average of 7 months and had increased compared with 2012 by an additional 2 months. Variability in resources were noted across provincial regions.

CONCLUSIONS

Over the past 10 years, ACHD care gaps have persisted, and personnel and infrastructure have not kept pace with estimates of ACHD population growth. Strategies are needed to improve and reduce disparity in ACHD care relative to training, staffing, and access to improved care for Canadians with ACHD.

The Impact of the COVID-19 Pandemic Restrictions on the Provision of Adult Congenital Heart Disease Care Across Canada: A National Survey

Background

The COVID-19 pandemic significantly impacted health care access across Canada with the reduction in in-person evaluations. The aim of the study was to examine the effects of the COVID-19 pandemic on access to health care services among the Canadian population with adult congenital heart disease (ACHD).

Methods

All Canadian adult congenital heart affiliated centres were contacted and asked to collect data on outpatient clinic and procedural volumes for the 2019 and 2020 calendar years. A survey was sent detailing questions on clinic and procedural volumes and wait times before and after pandemic restrictions. Descriptive statistics were used with the Student t-test to compare groups.

Results

In 2019, there were 19,326 ACHD clinic visits across Canada and only 296 (1.5%) virtual clinic visits. However, during the first year of the pandemic, there were 20,532 clinic visits and 11,412 (56%) virtual visits (P < 0.0001). There were no differences in procedural volumes (electrophysiology, cardiac surgery, and percutaneous intervention) between 2019 and 2020. The mean estimated wait times (months) before the pandemic vs the pandemic were as follows: nonurgent consult 5.4 ± 2.6 vs 6.6 ± 4.2 (P = 0.65), ACHD surgery 6.0 ± 3.5 vs 7.0 ± 4.6 (P = 0.47), electrophysiology procedures 6.3 ± 3.3 vs 5.7 ± 3.3 (P = 0.72), and percutaneous intervention 4.6 ± 3.9 vs 4.4 ± 2.3 (P = 0.74).

Conclusions

During the pandemic and restrictions of social distancing, the use of virtual clinic visits helped to maintain continuity in ACHD clinical care, with 56% of ACHD visits being virtual. The procedural volumes and wait times for consultation and percutaneous and surgical interventions were not delayed.

Neurophysiological mechanisms of exertional dyspnea in post-pulmonary embolism syndrome

Following pulmonary embolism (PE), a third of patients develop persistent dyspnea, which is commonly termed the post-PE syndrome. The neurophysiological underpinnings of exertional dyspnea in patients with post-PE syndrome without pulmonary hypertension (PH) are unclear. Thus, the current study determined if abnormally high inspiratory neural drive (IND) due, in part, to residual pulmonary gas-exchange abnormalities, was linked to heightened exertional dyspnea and exercise limitation, in such patients. Fourteen participants with post-PE syndrome (without resting PH) and 14 age-, sex-, and body mass index-matched healthy controls undertook pulmonary function testing and a symptom-limited cycle cardiopulmonary exercise test with measurements of IND (diaphragmatic electromyography), ventilatory requirements for CO₂ (V̇e/V̇co₂), and perceived dyspnea intensity (modified Borg 0-10 scale). Post-PE (vs. control) had a reduced resting transfer coefficient for carbon monoxide (K_CO: 84 ± 15 vs. 104 ± 14%pred, P < 0.001) and peak oxygen uptake (V̇o_2peak) (76 ± 14 vs. 124 ± 28%pred, P < 0.001). IND and V̇e/V̇co₂ were higher in post-PE than controls at standardized submaximal work rates (P < 0.05). Dyspnea increased similarly in both groups as a function of increasing IND but was higher in post-PE at standardized submaximal work rates (P < 0.05). High IND was associated with low K_CO (r = -0.484, P < 0.001), high V̇e/V̇co₂ nadir (r = 0.453, P < 0.001), and low V̇o_2peak (r = -0.523, P < 0.001). In patients with post-PE syndrome, exercise IND was higher than controls and was associated with greater dyspnea intensity. The heightened IND and dyspnea in post-PE, in turn, were strongly associated with low resting K_CO and high exercise V̇e/V̇co₂, which suggest important pulmonary gas-exchange abnormalities in this patient population.NEW & NOTEWORTHY This study is the first to show that increased exertional dyspnea in patients with post-pulmonary embolism (PE) syndrome, without overt pulmonary hypertension, was strongly associated with elevated inspiratory neural drive (IND) to the diaphragm during exercise, compared with healthy controls. The greater IND was associated with impairments in pulmonary gas exchange and significant deconditioning. Our results help to explain why many patients with post-PE syndrome report significant dyspnea at relatively low levels of physical activity.

Cardiovascular/Stroke Risk Assessment in Patients with Erectile Dysfunction-A Role of Carotid Wall Arterial Imaging and Plaque Tissue Characterization Using Artificial Intelligence Paradigm: A Narrative Review

PURPOSE

The role of erectile dysfunction (ED) has recently shown an association with the risk of stroke and coronary heart disease (CHD) via the atherosclerotic pathway. Cardiovascular disease (CVD)/stroke risk has been widely understood with the help of carotid artery disease (CTAD), a surrogate biomarker for CHD. The proposed study emphasizes artificial intelligence-based frameworks such as machine learning (ML) and deep learning (DL) that can accurately predict the severity of CVD/stroke risk using carotid wall arterial imaging in ED patients.

METHODS

Using the PRISMA model, 231 of the best studies were selected. The proposed study mainly consists of two components: (i) the pathophysiology of ED and its link with coronary artery disease (COAD) and CHD in the ED framework and (ii) the ultrasonic-image morphological changes in the carotid arterial walls by quantifying the wall parameters and the characterization of the wall tissue by adapting the ML/DL-based methods, both for the prediction of the severity of CVD risk. The proposed study analyzes the hypothesis that ML/DL can lead to an accurate and early diagnosis of the CVD/stroke risk in ED patients. Our finding suggests that the routine ED patient practice can be amended for ML/DL-based CVD/stroke risk assessment using carotid wall arterial imaging leading to fast, reliable, and accurate CVD/stroke risk stratification.

SUMMARY

We conclude that ML and DL methods are very powerful tools for the characterization of CVD/stroke in patients with varying ED conditions. We anticipate a rapid growth of these tools for early and better CVD/stroke risk management in ED patients.

Cardiovascular/Stroke Risk Stratification in Parkinson's Disease Patients Using Atherosclerosis Pathway and Artificial Intelligence Paradigm: A Systematic Review

Parkinson’s disease (PD) is a severe, incurable, and costly condition leading to heart failure. The link between PD and cardiovascular disease (CVD) is not available, leading to controversies and poor prognosis. Artificial Intelligence (AI) has already shown promise for CVD/stroke risk stratification. However, due to a lack of sample size, comorbidity, insufficient validation, clinical examination, and a lack of big data configuration, there have been no well-explained bias-free AI investigations to establish the CVD/Stroke risk stratification in the PD framework. The study has two objectives: (i) to establish a solid link between PD and CVD/stroke; and (ii) to use the AI paradigm to examine a well-defined CVD/stroke risk stratification in the PD framework. The PRISMA search strategy selected 223 studies for CVD/stroke risk, of which 54 and 44 studies were related to the link between PD-CVD, and PD-stroke, respectively, 59 studies for joint PD-CVD-Stroke framework, and 66 studies were only for the early PD diagnosis without CVD/stroke link. Sequential biological links were used for establishing the hypothesis. For AI design, PD risk factors as covariates along with CVD/stroke as the gold standard were used for predicting the CVD/stroke risk. The most fundamental cause of CVD/stroke damage due to PD is cardiac autonomic dysfunction due to neurodegeneration that leads to heart failure and its edema, and this validated our hypothesis. Finally, we present the novel AI solutions for CVD/stroke risk prediction in the PD framework. The study also recommends strategies for removing the bias in AI for CVD/stroke risk prediction using the PD framework.

Automated deep learning-based paradigm for high-risk plaque detection in B-mode common carotid ultrasound scans: an asymptomatic Japanese cohort study

BACKGROUND

The death due to stroke is caused by embolism of the arteries which is due to the rupture of the atherosclerotic lesions in carotid arteries. The lesion formation is over time, and thus, early screening is recommended for asymptomatic and moderate-risk patients. The previous techniques adopted conventional methods or semi-automated and, more recently, machine learning solutions. A handful of studies have emerged based on solo deep learning (SDL) models such as UNet architecture.

METHODS

The proposed research is the first to adopt hybrid deep learning (HDL) artificial intelligence models such as SegNet-UNet. This model is benchmarked against UNet and advanced conventional models using scale-space such as AtheroEdge 2.0 (AtheroPoint, CA, USA). All our resultant statistics of the three systems were in the order of UNet, SegNet-UNet, and AtheroEdge 2.0.

RESULTS

Using the database of 379 ultrasound scans from a Japanese cohort of 190 patients having moderate risk and implementing the cross-validation deep learning framework, our system performance using area-under-the-curve (AUC) for UNet, SegNet-UNet, and AtheroEdge 2.0 were 0.93, 0.94, and 0.95 (p<0.001), respectively. The coefficient of correlation between the three systems and ground truth (GT) were: 0.82, 0.89, and 0.85 (p<0.001 for all three), respectively. The mean absolute area error for the three systems against manual GT was 4.07±4.70 mm2, 3.11±3.92 mm2, 3.72±4.76 mm2, respectively, proving the superior performance SegNet-UNet against UNet and AtheroEdge 2.0, respectively. Statistical tests were also conducted for their reliability and stability.

CONCLUSIONS

The proposed study demonstrates a fast, accurate, and reliable solution for early detection and quantification of plaque lesions in common carotid artery ultrasound scans. The system runs on a test US image in < 1 second, proving overall performance to be clinically reliable.

Right Atrial Collision Time (RACT): a novel marker of propensity for typical atrial flutter

Background

The risk of typical atrial flutter (AFL) is increased by factors that increase right atrial (RA) size or cause scarring to reduce conduction velocity. These characteristics ensure the macro re-entrant wave front does not meet its refractory tail. The time taken to traverse the circuit would take account of both of these characteristics (being equal to distance divided by velocity), and may provide a superior marker of propensity to develop AFL.

Purpose

To investigate right atrial collision time (RACT) as a marker of typical AFL.

Methods

This single centre, prospective study recruited consecutive typical AFL ablation cases that were in sinus rhythm. Controls were consecutive cases other than atrial fibrillation and &gt;50 years of age. Exclusion criteria for both groups were a prior ablation in the RA and class I and III antiarrhythmics. While pacing the coronary sinus ostium at 600 ms, a local activation time map was created to locate the latest collision point on the anterolateral wall, excluding the RA appendage (Figure 1). This RACT approximates half a revolution.

Results

The AFL group's (n=34) mean RACT was 132.5±15.06 vs 98.7±12.23ms in the controls (n=40) (p&lt;0.01). No significant difference was observed for age (mean 65.6 vs 62.6 (p=0.18)), male (68.8% vs 60% (p=0.59)), body surface area (mean 2.1 vs 2.03 m2 (p=0.24)). The RACT also proved to be a superior marker than the echocardiographic measurement of right atrial area in an apical four chamber view (mean 17.8 vs 16.3 cm2 (p=0.21).A ROC curve indicated an AUC of 0.97 (95% CI: 0.93–1.0, p&lt;0.01). A RACT cut-off of 120 ms had a specificity of 99% and a sensitivity of 75%.

Conclusion

RACT is a novel and promising marker of propensity for typical AFL. The ability to predict AFL would be of significant clinical value given the risk of stroke and frequent need for ablation.

Funding Acknowledgement

Type of funding source: None

1681 Carotid screening prior to stress echocardiography, an opportunity to assess cardiovascular risk?

BACKGROUND

Screening for atherosclerosis is an important method for assessing cardiovascular (CV) risk. Our data with carotid imaging shows a normal a carotid is associated with a very low 10-year CV risk of 1.6%. Even a low risk carotid still predicts a favourable outcome, 5.6-7.0% CV risk over 10 years. Increasing plaque burden as assessed by either total plaque area (&gt;25mm2) or plaque score (&gt;1) is associated with increasing CV risk, ranging from 20% to &gt;30% over 10 years.

PURPOSE

This analysis was performed to estimate the prevalence and severity of carotid disease in men and women presenting for stress ECHO, with no prior documented evidence of CV disease.

METHODS

Data was collected from October 3, 2011 to January 22, 2019. Male patients aged 40-70yrs and female patients aged 50-75yrs undergoing stress ECHO underwent a screening carotid examination prior to the test. This involves only 2-3 images on each side to include, the CCA, carotid bulb and ICA. Maximal CCA IMT is measured using an automatic edge detection method, plaque score is calculated using the Rotterdam method and plaque area is measured in the carotid bulb and ICA bilaterally. Total plaque area being the sum of all area measurements. Apart from age criteria, patients were also excluded if they were diabetic, already taking a statin, or had a previous history of any vascular disease. A low-risk carotid was defined as a maximal CCA IMT &lt;1.00m,with a plaque score of "0" or "1" providing the total plaque area was &lt;25mm2. An unpaired t-test was used to detect differences between means and the Fisher’s exact test was used to detect differences between proportions. A p value of &lt;0.05 was considered statistically significant.

RESULTS

There were 1683 patients, 1175 females and 508 males with a mean age of 60.9 ± 7.4 years. Of the 1683 patients 1058 had evidence of carotid plaque (62.9%), 368 males (72.4%) and 690 females (58.7%). 726 patients were classified as low-risk and 957 patients were classified as high-risk. See Table 1.

CONCLUSIONS

A brief screening carotid examination prior to stress ECHO reveals a large percentage of both men and women who have evidence of atherosclerosis, of which 56.9% are high-risk. These patients could be identified while in the ECHO laboratory. The patients could then be offered guideline therapy with statin therapy and low dose ASA.

Table 1. Number Age CCA IMT PS 0-1 PS 2-3 PS 4-6 Low-risk High-risk Males 508 58.4 ± 7.8 1.14 ± 0.47 138 213 56 161 347 Females 1175 62.0 ± 7.0 0.99 ± 0.49 726 395 54 565 610 P value &lt;0.0001 &lt;0.0001 &lt;0.0001 &lt;0.005 &lt;0.0001 &lt;0.0001 &lt;0.0001 PS = Plaque score.

P4402Effect of carnitine supplementation on progression of carotid plaque in the metabolic syndrome: the ECoM study

Background/Introduction

L-carnitine (L-C) has been investigated as a potential therapy for cardiovascular (CV) disease, but its direct effects on human atherosclerosis are unknown. Epidemiological studies suggest a possible reduction of CV risk factors following treatment, whereas animal studies have shown that L-C may increase pro-atherogenic metabolites.

Purpose

The purpose of this study was to determine whether L-C therapy led to atherosclerosis progression or regression by direct quantification of carotid atherosclerotic lesions in patients with metabolic syndrome (MetS).

Methods

This study was a Phase 2, prospective, parallel, double blinded, randomized, placebo-controlled, two-center trial. MetS was defined according to the International Diabetes Federation harmonized definition, where presence of any 3 of the 5 following risk factors constituted a diagnosis: elevated waist circumference; elevated triglycerides; reduced HDL or treated; elevated blood pressure or treated; elevated glucose or HbA1c or treated. Participants with a baseline carotid total plaque volume (TPV) ≥50 mm3 were randomized to placebo or 2 g L-C daily for 6 months. Plaque progression was quantified by 3D carotid ultrasound for change in TPV and reduction in vessel lumen area (% area stenosis, Fig. 1). Absolute differences were assessed on the raw scale, while percent change on the log scale. Analysis of covariance (ANCOVA) was used to assess within- and between-arm differences.

Results

Of the 177 participants randomized, 157 completed the study (L-C n=76, placebo n=81). No statistically significant difference between arms was found in the primary outcome (TPV). However, there was progression of plaque stenosis in the treatment arm: the L-C group had an increase in stenosis of 9.8% (p=0.01) higher than the placebo arm, and a 2.7% (p=0.03) greater absolute change. Total cholesterol and LDL levels (0.10 mmol/L and 0.05 mmol/L, respectively) were higher in the intervention arm compared to the placebo arm (−0.06 mmol/L and −0.07 mmol/L).

Figure 1

Conclusions

We observed progression of atherosclerosis with L-C therapy compared to placebo in patients with MetS. The clear lack of benefit of L-C therapy in this population raises serious concerns for its further use as a potential therapy. Given its association with pro-atherogenic metabolites our study offers further understanding of the atherosclerotic process.

Acknowledgement/Funding

Heart and Stroke Foundation of Canada

3042Gender differences in the prevalence of a normal IMT with increasing severity of carotid disease

Background

The ARIC group has shown that increasing IMT is only predictive of increased cardiovascular (CV) risk in males (M). Plaque is predictive of increased CV risk in both M and females (F).

Purpose

To determine the prevalence of a normal IMT (<1.00mm) in M and F with evidence of carotid plaque. Plaque score (PS) was used as a measure of severity of disease.

Methods

Our database was searched for patients with all the required data, IMT, PS and plaque area. IMT was measured with automatic edge detection software, PS was calculated using the Rotterdam method and plaque area was measured in the carotid bulb and ICA bilaterally. Only the first carotid study was used in the analysis. PS of 0–6 were used to estimate plaque severity. ANOVA and the Fisher's exact test were used to detect differences between groups. A p value of <0.05 was considered significant.

Results

There were 5981 patients, 3062 M and 2919 F with an average age of 62.1±11.3 years. Table I. indicates that with increasing PS, age, IMT and plaque area all increase, with a reciprocal decrease in the proportion of patients with a normal IMT. Of 3829 patients with carotid plaque 1355 (35.4%) had an IMT <1.00mm. There were clear gender differences with a much higher prevalence of a normal IMT in F with carotid plaque than M, 776 of 1772 (43.8%) versus 579 of 2057 (28.1%), p<0.0001, Fisher's exact test. This gender difference applies to most groups with increasing plaque burden except those with the most severe disease (PS “5–6”).

Table 1 PS “0” PS “1” PS “2” PS “3” PS “4” PS “5–6” N 2152 896 1209 792 562 370 ANOVA Age 57.6±12.2 60.4±9.2 63.0±9.5 66.5±9.3 67.8±8.9 71.5±8.8 <0.0001 IMT 0.94±0.32 1.00±0.23 1.08±0.29 1.30±0.55 1.51±0.75 2.77±0.88 <0.0001 Plaque area 0 16.5±11.6 35.1±20.0 58.6±29.9 91.0±43.1 130.4±61.3 <0.0001 Males 1005 424 627 422 331 253 IMT <1.00mm 671 222 226 77 50 4 Percentage 66.8% 52.4% 36.0% 18.2% 15.1% 1.6% Females 1147 472 582 370 231 117 IMT <1.00mm 879 293 288 136 57 2 Percentage 76.6% 62.1% 49.5% 36.8% 24.6% 1.7% Fisher's test <0.0001 <0.005 <0.0001 <0.0001 <0.0001 NS PS = Carotid ÷ 6 segments, assigned “0” or “1” if plaque is absent or present.

Conclusions

Significantly more women with carotid plaque have a normal IMT. This may explain why IMT fails to be predictive of CV risk in women.

Association Between Transthoracic Echocardiography Appropriateness and Echocardiographic Findings

BACKGROUND

The association between appropriate use criteria and echocardiographic findings in patients with chronic cardiovascular diseases is unknown.

METHODS

As a substudy of the Echo WISELY (Will Inappropriate Scenarios for Echocardiography Lessen Significantly) trial, 9,230 transthoracic echocardiographic (TTE) examinations from six Ontario academic hospitals were linked to a registry of echocardiographic findings. The TTE studies were rated appropriate), rarely appropriate, or may be appropriate according to the 2011 appropriate use criteria. TTE findings of appropriately ordered examinations were compared with those of rarely appropriate examinations for specific disease subsets, including heart failure and valvular heart disease.

RESULTS

There were 7,574, 1,087, and 569 TTE examinations ordered for appropriate, rarely appropriate, and may be appropriate indications, and of the 7,574 appropriate studies, 6,399 were ordered for specific indications and 1,175 for general indications. TTE examinations ordered for general indications had lower rates of left ventricular dysfunction (19.6% vs 9.1%, P < .001) and moderate to severe aortic stenosis (15.5% vs 2.6%, P < .001). Of the 2,395 TTE examinations ordered for patients with heart failure, appropriately ordered studies were more likely to result in left ventricular segmental abnormality (37.0% vs 24.9%, P = .012) but similar rates of right ventricular dilatation (15.4% vs 14.7%, P = .79), right ventricular dysfunction (14.8% vs 11.3%, P = .22), and moderate to severe mitral regurgitation (12.1% vs 9.2%, P = .35). Of the 2,859 studies ordered to assess valvular heart disease, appropriately ordered studies were significantly more likely to find moderate to severe valvular pathology, including aortic stenosis (30.4% vs 24.6%, P = .008), aortic regurgitation (8.9% vs 1.6%, P < .001), mitral stenosis (6.7% vs 3.1%, P = .002), and mitral regurgitation (16.1% vs 6.1%, P < .001), but similar rates of tricuspid regurgitation (11.2% vs 13.0%, P = .60).

CONCLUSIONS

Overall, appropriately ordered TTE examinations for heart failure and valvular heart disease were significantly more likely to have abnormal findings than rarely appropriate examinations. TTE studies ordered for general indications had fewer, although still a significant proportion, of abnormalities compared with studies ordered for specific indications.

Design and methods of the Echo WISELY (Will Inappropriate Scenarios for Echocardiography Lessen SignificantlY) study: An investigator-blinded randomized controlled trial of education and feedback intervention to reduce inappropriate echocardiograms

BACKGROUND

Appropriate use criteria (AUC) for transthoracic echocardiography (TTE) were developed to address concerns regarding inappropriate use of TTE. A previous pilot study suggests that an educational and feedback intervention can reduce inappropriate TTEs ordered by physicians in training. It is unknown if this type of intervention will be effective when targeted at attending level physicians in a variety of clinical settings.

AIMS

The aim of this international, multicenter study is to evaluate the hypothesis that an AUC-based educational and feedback intervention will reduce the proportion of inappropriate echocardiograms ordered by attending physicians in the ambulatory environment.

METHODS

In an ongoing multicentered, investigator-blinded, randomized controlled trial across Canada and the United States, cardiologists and primary care physicians practicing in the ambulatory setting will be enrolled. The intervention arm will receive (1) a lecture outlining the AUC and most recent available evidence highlighting appropriate use of TTE, (2) access to the American Society of Echocardiography mobile phone app, and (3) individualized feedback reports e-mailed monthly summarizing TTE ordering behavior including information on inappropriate TTEs and brief explanations of the inappropriate designation. The control group will receive no education on TTE appropriate use and order TTEs as usual practice.

CONCLUSIONS

The Echo WISELY (Will Inappropriate Scenarios for Echocardiography Lessen Significantly in an education RCT) study is the first multicenter randomized trial of an AUC-based educational intervention. The study will examine whether an education and feedback intervention will reduce the rate of outpatient inappropriate TTEs ordered by attending level cardiologists and primary care physicians (www.clinicaltrials.gov identifier NCT02038101).