Impact of the COVID-19 pandemic on provision of interventional cardiology and cardiac surgery services in Australia: a review of Medicare claims data.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has significantly impacted healthcare service provision worldwide. There is limited information on changes in invasive cardiovascular services during the pandemic, particularly in Australia. AIM: We sought to assess temporal trends on the use of interventional cardiology and cardiac surgery services before and following the COVID-19 pandemic in Australia. METHODS: Medicare Benefits Schedule items data from the Australian Government Services Australia on outpatient and private hospital interventional cardiology procedures (coronary angiogram, percutaneous coronary intervention and transcatheter aortic valve implantation) and cardiac surgery procedures (coronary artery bypass grafting [CABG] and surgical valve replacement, repair and annuloplasty) were analysed from March 2019 to 2021. This was superimposed on monthly COVID-19 case data obtained from the Australian Department of Health and Aged Care epidemiology reports. RESULTS: A sustained reduction in CABG (-10.1%) and surgical valve intervention (-11.1%) was appreciated from March 2019-2020 to March 2020-2021, in the first year of the COVID-19 pandemic. During this period, an overall increase (+25.9%) in the use of transcatheter aortic valve implantation was observed. Following the initial period of mandated isolation in March-April 2020, a reduction in coronary angiography (-29.1%) and percutaneous coronary intervention (-19.5%) was observed in comparison to March-April 2019; however, this was largely attenuated over time. CONCLUSIONS: The COVID-19 pandemic has resulted in reductions in the use of interventional cardiology and cardiac surgery services, with cardiac surgery most affected. However, an increase in uptake of transcatheter aortic valve implantation has been observed during the pandemic. This may have implications for future planning and resource allocation in the aftermath of the pandemic.

Association between vessel-specific coronary Aggregated plaque burden, Agatston score and hemodynamic significance of coronary disease (The CAPTivAte study).

Background: CT coronary angiography (CTCA) is a guideline-endorsed assessment for patients with stable angina and suspected coronary disease. Although associated with excellent negative predictive value in ruling out obstructive coronary disease, there are limitations in the ability of CTCA to predict hemodynamically significant coronary disease. The CAPTivAte study aims to assess the utility of Aggregated Plaque Burden (APB) in predicting ischemia based on Fractional Flow Reserve (FFR). Methods: In this retrospective study, patients who had a CTCA and invasive FFR of the LAD were included. The entire length of the LAD was analyzed using semi-automated software which characterized total plaque burden and plaque morphological subtype (including Low Attenuation Plaque (LAP), Non-calcific plaque (NCP) and Calcific Plaque (CP). Aggregated Plaque Burden (APB) was calculated. Univariate and multivariate analysis were performed to assess the association between these CT-derived parameters and invasive FFR. Results: There were 145 patients included in this study. 84.8 % of patients were referred with stable angina. There was a significant linear association between APB and FFR in both univariate and multivariate analysis (Adjusted R-squared = 0.0469; p = 0.035). Mean Agatston scores are higher in FFR positive vessels compared to FFR negative vessels (371.6 (±443.8) vs 251.9 (±283.5, p = 0.0493). Conclusion: CTCA-derived APB is a reliable predictor of ischemia assessed using invasive FFR and may aid clinicians in rationalizing invasive vs non-invasive management strategies. Vessel-specific Agatston scores are significantly higher in FFR-positive vessels than in FFR-negative vessels. Associations between HU-derived plaque subtype and invasive FFR were inconclusive in this study.

Aortic Stenosis and Renal Function: A Bidirectional Mendelian Randomization Analysis.

BACKGROUND: Large observational studies have demonstrated a clear inverse association between renal function and risk of aortic stenosis (AS). Whether this represents a causal, reverse causal or correlative relationship remains unclear. We investigated this using a bidirectional 2-sample Mendelian randomization approach. METHODS AND RESULTS: We collected summary statistics for the primary analysis of chronic kidney disease (CKD) and AS from genome-wide association study meta-analyses including 480 698 and 653 867 participants, respectively. We collected further genome-wide association study summary statistics from up to 1 004 040 participants for sensitivity analyses involving estimated glomerular filtration rate (eGFR) derived from creatinine, eGFR derived from cystatin C, and serum urea nitrogen. Inverse-variance weighted was the primary analysis method, with weighted-median, weighted-mode, Mendelian randomization-Egger, and Mendelian randomization-Pleiotropy Residual Sum and Outlier as sensitivity analyses. We did not find evidence of a causal relationship between genetically predicted CKD liability as the exposure and AS as the outcome (odds ratio [OR], 0.94 per unit increase in log odds of genetic liability to CKD [95% CI, 0.85-1.04], P=0.26) nor robust evidence of AS liability as the exposure and CKD as the outcome (OR, 1.04 per unit increase in log odds of genetic liability to AS [95% CI, 0.97-1.12], P=0.30). The sensitivity analyses were neutral overall, as were the analyses using eGFR derived from creatinine, eGFR derived from cystatin C, and serum urea nitrogen. All positive controls demonstrated strong significant associations. CONCLUSIONS: The present study did not find evidence of a substantial effect of genetically predicted renal impairment on risk of AS. This has important implications for research efforts that attempt to identify prevention and treatment targets for both CKD and AS.