Macrotroponin in the COVID-19 Era: An Under-Recognised Cause of Persistent Troponin Elevation

Troponin is an important diagnostic tool, however, as the assay sensitivity and frequency of testing has increased in the COVID-19 era, a new cohort of patients with persistently elevated troponin has emerged. Interfering antibodies should be considered in patients with persistent and stable troponin elevation, where there is no ongoing cause.

Strain Assessment in Aortic Stenosis: Pathophysiology and Clinical Utility

Contemporary echocardiographic criteria for grading aortic stenosis severity have remained relatively unchanged, despite significant advances in noninvasive imaging techniques over the last 2 decades. More recently, attention has shifted to the ventricular response to aortic stenosis and how this might be quantified. Global longitudinal strain, semiautomatically calculated from standard two-dimensional echocardiographic images, has been the focus of extensive research. Global longitudinal strain is a sensitive marker of subtle hypertrophy-related impairment in left ventricular function and has shown promise as a relatively robust prognostic marker, both independently and when added to severity classification systems. Herein we review the pathophysiological basis underpinning the potential utility of global longitudinal strain in the assessment of aortic stenosis, as well as its potential role in quantifying myocardial recovery and prognostic discrimination following aortic valve replacement.

Advanced Proteomics and Cluster Analysis for Identifying Novel Obstructive Sleep Apnea Subtypes before and after Continuous Positive Airway Pressure Therapy

Rationale: Studies have shown elevated inflammatory biomarkers in obstructive sleep apnea (OSA), but data after continuous positive airway pressure (CPAP) treatment are inconsistent. Objectives: We used the Olink proteomics panel to identify unique OSA clusters on the basis of inflammatory protein expression and assess the impact of CPAP therapy. Methods: Adults with newly diagnosed OSA had blood drawn at baseline and three to four months after CPAP. Samples were analyzed using the Olink proteomics platform, which measures 92 prespecified inflammatory proteins using proximity extension assay. Linear mixed-effects models were used to model changes in protein expression during the period of CPAP use, adjusting for batch, age, and sex. Unsupervised hierarchical clustering was performed to identify unique inflammatory OSA clusters on the basis of inflammatory biomarkers. Within-cluster impact of CPAP on inflammatory protein expression was assessed. Results: Among 46 patients, the mean age was 46 ± 12 years (22% women), mean body mass index was 31 ± 5 kg/m2, and mean respiratory disturbance index was 33 ± 17 events/hour. Unsupervised cluster and heatmap analysis revealed three unique proteomic clusters, with low (n = 21), intermediate (n = 19), and high (n = 6) inflammatory protein expression. After CPAP, there were significant within-cluster differences in protein expression. The low inflammatory cluster had a significant increase in protein expression (16%; P = 0.02), and the high inflammatory cluster had a significant decrease in protein expression (-20%; P = 0.003), more significant among those compliant with CPAP in the low (25%; P = 0.04) and high (-22%; P = 0.01) clusters. Conclusions: We identified three unique inflammatory clusters in patients with OSA using plasma proteomics, with a differential response to CPAP by cluster. Our results are hypothesis generating and require further investigation in larger longitudinal studies for enhanced cardiovascular risk profiling in OSA.

O036 Does Cxbladder accurately exclude bladder urothelial cell malignancy on diagnostic and surveillance cystoscopy? a prospective multi-centre study

Introduction and Objectives

Health systems incur significant costs from bladder cancer. Diagnostic and surveillance protocols are intensive. Urine cytology and Computed tomography (CT) have low sensitivity as screening and surveillance tools. Cxbladder is a non-invasive urinary biomarker approved for use in Australia, with high reported sensitivity in bladder cancer detection. The purpose of this study was to determine the accuracy of Cxbladder as a screening and surveillance tool in patients with suspected and established bladder cancer, respectively.

Methods

A prospective trial (88 participants) was performed at Gosford and North Gosford Hospitals (New South Wales, Australia). Inclusion criteria were: patients undergoing investigation for macroscopic haematuria or bladder cancer surveillance. Patients were asked to perform a Cxbladder test prior to either flexible or rigid cystoscopy. Exclusion criteria were: patients aged < 18 years, or patients that had undergone transurethral resection of the bladder within five months. Testing kits were supplied at no cost by Pacific Edge Ltd. Cxbladder results were then compared with cystoscopic findings, the prevailing gold-standard for bladder cancer diagnosis.

Results

Sensitivity and specificity of Cxbladder for detection of bladder cancer were 76.5% and 45.1% respectively. Positive and negative predictive values (PPV/NPV) were 31.7% and 85% respectively. False negative cases comprised low-grade papillary tumours only. Cxbladder had 100% NPV in detection of high-risk bladder cancer.

Conclusion

There is evidence to support Cxbladder as a screening tool in the detection of high-risk bladder cancer. Further studies involving larger populations are required to validate its accuracy.

Take-home message

The purpose of this study was to determine the accuracy of Cxbladder as a screening and surveillance tool in patients with suspected and established bladder cancer, respectively. Sensitivity and specificity of Cxbladder for detection of bladder cancer were 76.5% and 45.1% respectively, whilst a 100% negative predictive value was obtained in detection of high-risk bladder cancer.

Spontaneous Coronary Artery Dissection (SCAD) and a family history of aortic artery dissection, a case series

Background/Introduction

SCAD typically affects women in their fifth or sixth decade with a paucity of cardiovascular risk factors.(1) It is caused by a coronary artery intramural haematoma with or without intimal tear. Resultant luminal occlusion manifests as myocardial ischaemia/infarction or death.

There are two published sporadic cases of SCAD who developed iatrogenic aortic dissection with coronary angiography.(2, 3) We are not aware of any SCAD cases with intercurrent or historical spontaneous aortic dissection. There is a published SCAD case with a familial history of aortic dissection, in her mother.(4) None of these cases reported a connective tissue disorder.

Methods

We searched our database of 338 SCAD cases, recruited via social media or cardiologist referral, for cases with a family history of aortic dissection. SCAD diagnosis was confirmed by review of coronary angiogram images by an expert interventional cardiologist blinded to the genetic analysis.

Genomic DNA was extracted from buccal cells collected using a cheek swab or mouthwash sample. Whole genome sequencing was performed using the Illumina HiSeq X Ten platform with 30x coverage.

These data are being analysed for rare variants in genes associated with familial aortopathies or connective tissue disorders (e.g. FBN1, COL3A1, TGFbR-1/2, SMAD3), as well as for novel gene associations with aortic dissection and/or SCAD.

Results

We identified 12 cases with a first- or second-degree relative with aortic dissection. Of these SCAD cases, 11 were female whereas 10 of 12 relatives with aortic dissection were male. In one instance, a maternal uncle, but not the index SCAD case, had Marfan's syndrome.

Whole genome sequencing has been performed on the 12 SCAD cases, 2 living relatives with aortic dissection and 2 relatives linking the SCAD and aortic dissection cases.

Conclusions

Coronary and aortic dissections have serious consequences and in some families there may be a genetic association between the two conditions. Early identification of variant carriers is critical for disease prevention.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): This work was supported in part by grants from the Cardiac Society of Australia and New Zealand, the National Health and Medical Research Council, Australia (APP1161200), the St Vincent's Clinic Foundation, the Catholic Archdiocese of Sydney, Perpetual Philanthropy, NSW Health and SCAD Research Inc. LMC is funded by a University Postgraduate Scholarship through University of NSW and a grant from the Avant Foundation.

Prognostic Impact of High-Sensitivity C-Reactive Protein in Patients Undergoing Percutaneous Coronary Intervention According to BMI

OBJECTIVES

The aim of this study was to determine the prevalence and prognostic implications of elevated high-sensitivity C-reactive protein (hsCRP) in patients undergoing percutaneous coronary intervention (PCI) according to body mass index (BMI).

BACKGROUND

Whereas elevated hsCRP predicts adverse clinical outcome after PCI in the general population, the impact of BMI on its prognostic utility remains unclear.

METHODS

Data from 14,140 patients who underwent PCI between January 2009 and June 2017 at a large tertiary care center were analyzed. Patients were divided into 4 BMI categories: normal (BMI 18.5 to <25 kg/m², n = 2,808), overweight (BMI 25 to <30 kg/m², n = 6,015), obese (BMI 30 to <35 kg/m², n = 3,490), and severely obese (BMI ≥35 kg/m², n = 1,827). Elevated hsCRP was defined as >3 mg/l. The primary endpoint of interest was the occurrence of major adverse cardiac events (MACE; defined as death, myocardial infarction, or target vessel revascularization) within 1 year after PCI.

RESULTS

Elevated hsCRP was present in 18.9%, 23.6%, 33.3%, and 47.7% of the normal, overweight, obese, and severely obese groups, respectively. MACE rates were consistently higher in patients with elevated hsCRP across all BMI categories (normal, 13.4% vs. 8.3%; overweight, 11.2% vs. 7.2%; obese, 10.6% vs. 7.5%; severely obese, 11.9% vs. 6.5%; p < 0.01 for all). After multivariate adjustment, hsCRP elevation remained significantly associated with MACE independent of BMI (hazard ratios: normal, 1.43 [95% confidence interval: 1.04 to 1.95]; overweight, 1.56 [95% confidence interval: 1.21 to 1.88]; obese, 1.40 [95% confidence interval: 1.06 to 1.84]; severely obese, 1.92 [95% confidence interval: 1.35 to 2.75]; p < 0.05 for all).

CONCLUSIONS

Among patients undergoing PCI, the prevalence of hsCRP elevation progressively increased with higher BMI. Measurement of hsCRP facilitates prognostic risk assessment for adverse outcome after PCI across a broad range of BMI.

Spontaneous Coronary Artery Dissection and Fibromuscular Dysplasia: Vasculopathies With a Predilection for Women

The burden of cardiovascular disease in women is being increasingly appreciated. Nevertheless, both clinicians and the general public are largely unaware that cardiovascular disease is the leading cause of death worldwide in women in all countries and that outcomes after a heart attack are worse for women than men. Of note, certain types of cardiovascular disease have a predilection for women, including spontaneous coronary artery dissection (SCAD) and fibromuscular dysplasia (FMD). Although uncommon, SCAD is being increasingly recognised as the cause of an acute coronary syndrome (ACS) and can recur. It is a potentially fatal, under-diagnosed condition that affects relatively young women, who often have few traditional risk factors, and is the commonest cause of a myocardial infarction associated with pregnancy. In contrast, FMD often remains silent but when manifested can also cause major sequelae, including renal infarction, stroke, cervical artery dissection and gut infarction. Here we provide an update on the diagnosis, aetiology and management of these important disorders that overwhelmingly affect women.

Non-coding RNA in endothelial-to-mesenchymal transition

Endothelial-to-mesenchymal transition (EndMT) is the process wherein endothelial cells lose their typical endothelial cell markers and functions and adopt a mesenchymal-like phenotype. EndMT is required for development of the cardiac valves, the pulmonary and dorsal aorta, and arterial maturation, but activation of the EndMT programme during adulthood is believed to contribute to several pathologies including organ fibrosis, cardiovascular disease, and cancer. Non-coding RNAs, including microRNAs, long non-coding RNAs, and circular RNAs, modulate EndMT during development and disease. Here, we review the mechanisms by which non-coding RNAs facilitate or inhibit EndMT during development and disease and provide a perspective on the therapeutic application of non-coding RNAs to treat fibroproliferative cardiovascular disease.

Impact of Diabetes Mellitus on Ischemic Events in Men and Women After Percutaneous Coronary Intervention

Studies have shown worse outcome for women compared with men after percutaneous coronary intervention (PCI), especially in the presence of diabetes mellitus (DM). We aimed to investigate the risk of ischemic events after PCI in women versus men stratified by the presence or absence of DM. A total of 17,154 consecutive patients from a single-center PCI registry enrolled from January 2009 to December 2014 were categorized accordingly: female/non-DM, female/DM, male/non-DM, and male/DM. End points included death and myocardial infarction (MI) at 1 year. Of the overall population, 15% (n = 2,631) were female/non-DM, 17% (n = 2,891) were female/DM, 38% (n = 6,483) were male/non-DM, and 30% (n = 5,149) were male/DM. Within the 4 study groups, female/DM had the highest risk, whereas female/non-DM and male/DM showed similar risks and male/non-DM showed lowest risk for death (4.64% vs 3.08% vs 2.93% vs 2.31%; p-trend <0.0001 over all groups and p = 0.69 between female/non-DM and male/DM, respectively) and MI (4.15% vs 3.99% vs 3.71% vs 2.55%; p trend <0.0001 over all groups and p = 0.97 between female/non-DM and male/DM, respectively). After multivariate adjustment findings were largely unchanged suggesting highest risk for adverse events in diabetic women compared with other groups and comparable risks for death and MI in nondiabetic women compared with diabetic men. In conclusion, these findings highlight the combined influence of DM and female gender as strong determinants of post-PCI risk while also illustrating "risk equivalence" between nondiabetic women versus diabetic men.