Publications by Year: 2022

BACKGROUND: Aortic stenosis is the most common cardiac valve disorder requiring clinical management. However, there is little evidence on the societal cost of progressive aortic stenosis. We sought to quantify the societal burden of premature mortality associated with progressively worse aortic stenosis.

METHODS: In this observational clinical cohort study, we examined echocardiograms on native aortic valves of 98 565 men and 99 357 women aged 65 years or older across 23 sites in Australia, from Jan 1, 2003, to Dec 31, 2017. Individuals were grouped according to their peak aortic valve velocity in 0·50 m/s increments up to 4·00 m/s or more (severe aortic stenosis), using 1·00-1·99 m/s (no aortic stenosis) as the reference group. Sex-specific premature mortality and years of life lost during a 5-year follow-up were calculated, along with willingness-to-pay to regain quality-adjusted life years (QALYs).

FINDINGS: Overall, 20 701 (21·0%) men and 18 576 (18·7%) women had evidence of mild-to-severe aortic stenosis. The actual 5-year mortality in men with normal aortic valves was 32·1% and in women was 26·1%, increasing to 40·9% (mild aortic stenosis) and 52·2% (severe aortic stenosis) in men and to 35·9% (mild aortic stenosis) and 55·3% (severe aortic stenosis) in women. Overall, the estimated societal cost of premature mortality associated with aortic stenosis was AU$629 million in men and $735 million in women. Per 1000 men and women investigated, aortic stenosis was associated with eight more premature deaths in men resulting in 32·5 more QALYs lost (societal cost of $1·40 million) and 12 more premature deaths in women resulting in 57·5 more QALYs lost (societal cost of $2·48 million) when compared with those without aortic stenosis.

INTERPRETATION: Any degree of aortic stenosis in older individuals is associated with premature mortality and QALYs. In this context, there is a crucial need for cost-effective strategies to promptly detect and optimally manage this common condition within our ageing populations.

FUNDING: Edwards LifeSciences, National Health and Medical Research Council of Australia, and the National Heart, Lung, and Blood Institute.

BACKGROUND: Administrative claims for aortic stenosis (AS) regurgitation may be useful, but their accuracy and ability to identify individuals at risk for valve-related outcomes have not been well characterized.

METHODS: Using echocardiographic (transthoracic echocardiogram [TTE]) reports linked to US Medicare claims, 2017 to 2018, the performance of candidate International Classification of Diseases, Tenth Revision claims to ascertain AS/aortic regurgitation was evaluated. The optimal performing algorithm was tested against outcomes at 1-year after TTE in a separate 100% sample of US Medicare claims, 2017 to 2019.

RESULTS: Of those included in the derivation (N=5497, mean age 74.4±11.0 years, 49.7% female), any AS or aortic regurgitation was present in 24% and 38.8%, respectively. The sensitivity and specificity of International Classification of Diseases, Tenth Revision code I35.0 for identification of any AS was 53.1% and 94.8%, respectively. Among those with an I35.0 code, 40.3% had severe AS. Claims were unable to distinguish disease severity (ie, severe versus nonsevere) or subtype (eg, bicuspid or rheumatic AS), and were insensitive and nonspecific for aortic regurgitation of any severity. Among all beneficiaries who received a TTE (N=4 033 844), adjusting for age, sex, and 27 comorbidities, those with an I35.0 code had a higher adjusted risk of all-cause mortality (adjusted hazard ratio, 1.33 [95% CI, 1.31-1.34]), heart failure hospitalization (adjusted hazard ratio, 1.37 [95% CI, 1.34-1.41]), and aortic valve replacement (adjusted hazard ratio, 34.96 [95% CI, 33.74-36.22]).

CONCLUSIONS: Among US Medicare beneficiaries receiving a TTE, International Classification of Diseases, Tenth Revision claims, though identifying a population at significant greater risk of valve-related outcomes, failed to identify nearly half of individuals with AS and were unable to distinguish disease severity or subtype. These results argue against the widespread use of International Classification of Diseases, Tenth Revision claims to screen for patients with AS and suggests the need for improved coding algorithms and alternative systems to extract TTE data for quality improvement and hospital benchmarking.

PURPOSE OF REVIEW: Ultrasound enhancing agents (UEAs), microbubbles which are composed of lipid or albumin shells containing high molecular weight gases with nonlinear acoustic properties in the ultrasound field, are important components of the diagnostic armamentarium in echocardiography. This review highlights the substantial value of UEAs in delineating endocardial border definition and influencing downstream decision-making in cardiovascular ultrasound.

RECENT FINDINGS: In this article, we review recent updates to the clinical applications of UEAs, special circumstances regarding use, the impact of use on downstream testing and cost-effectiveness, and recommended approaches for optimizing workflow in the echocardiography laboratory with UEAs.

SUMMARY: In multiple studies, UEAs have been identified as a useful tool in echocardiography, improving study accuracy and reader confidence, while reducing downstream testing and procedures and resulting in significant changes in clinical management. Despite their proven efficacy and cost-effectiveness, recent studies have suggested utilization remains low, in part due to perceived concerns and workflow issues that impair uptake. With an increasingly broader list of indications for echocardiography, UEAs will continue to play an important role in the diagnosis and management of patients with cardiovascular and noncardiovascular diseases.

The association of mitral regurgitation (MR) severity and mortality in heart failure with preserved ejection fraction (HFpEF) is uncertain. We sought to evaluate the relation between MR severity on transthoracic echocardiography (TTE) and subsequent all-cause mortality in Medicare beneficiaries with HFpEF. We linked 57,608 patients referred for TTE at Beth Israel Deaconess Medical Center to Medicare inpatient claims from 2003 to 2017. In those with a history of HF and a physician-reported left ventricular ejection fraction ≥50%, we evaluated the relation of MR severity and time to the primary end point of all-cause mortality using Kaplan-Meier methods. A total of 7,778 individuals (14.5%) met inclusion criteria (mean age 75.5 years ± 11.9, 55.9% female). Over a median follow-up of 8.1 years, 2,016 (25.9%) died at a median (interquartile range) of 1.7 (0.3 to 4.1) years. At 1 year, 15.8% with 3 to 4+ MR had died versus 10.5% with 0 to 2+ MR (hazard ratio 1.54, 95% confidence interval 1.22 to 1.95, p <0.001). After multivariable adjustment, 3 to 4+ MR continued to be associated with increased all-cause mortality (hazard ratio 1.48, 95% confidence interval 1.14 to 1.94, p = 0.004) except in the subset with atrial fibrillation (interaction p = 0.03) or recent (<3 months) HF hospitalization (p = 0.54). In conclusion, in this large, single-institution retrospective study of Medicare beneficiaries with HFpEF who underwent TTE, moderate-to-severe and severe MR were significantly associated with an increased risk of all-cause mortality after multivariable adjustment, except in those with atrial fibrillation or recent HF. Prospective studies are needed to assess the role of MR reduction in mitigating this risk.

AIMS: Prediction of mitral (MR) and tricuspid (TR) regurgitation progression on transthoracic echocardiography (TTE) is needed to personalize valvular surveillance intervals and prognostication.

METHODS AND RESULTS: Structured TTE report data at Beth Israel Deaconess Medical Center, 26 January 2000-31 December 2017, were used to determine time to progression (≥1+ increase in severity). TTE predictors of progression were used to create a progression score, externally validated at Massachusetts General Hospital, 1 January 2002-31 December 2019. In the derivation sample (MR, N = 34 933; TR, N = 27 526), only 5379 (15.4%) individuals with MR and 3630 (13.2%) with TR had progression during a median interquartile range) 9.0 (4.1-13.4) years of follow-up. Despite wide inter-individual variability in progression rates, a score based solely on demographics and TTE variables identified individuals with a five- to six-fold higher rate of MR/TR progression over 10 years (high- vs. low-score tertile, rate of progression; MR 20.1% vs. 3.3%; TR 21.2% vs. 4.4%). Compared to those in the lowest score tertile, those in the highest tertile of progression had a four-fold increased risk of mortality. On external validation, the score demonstrated similar performance to other algorithms commonly in use.

CONCLUSION: Four-fifths of individuals had no progression of MR or TR over two decades. Despite wide interindividual variability in progression rates, a score, based solely on TTE parameters, identified individuals with a five- to six-fold higher rate of MR/TR progression. Compared to the lowest tertile, individuals in the highest score tertile had a four-fold increased risk of mortality. Prediction of long-term MR/TR progression is not only feasible but prognostically important.

BACKGROUND: In response to COVID-19 pandemic state restrictions, our institution deferred elective procedures from 3/15/2020 to 6/13/2020, and removed cardiology fellows from the echocardiography rotation to staff clinical services. We assessed the impact of the COVID-19 pandemic on fellow education and echocardiography volumes.

METHODS: Our institutional database was used to examine volumes of transthoracic (TTE), stress (SE), and transesophageal echocardiograms (TEE) from 7/1/2018 to 10/10/2020. Study volumes were compared in three intervals: pre-pandemic (7/1/2018- 3/14/2020), pandemic (3/15/2020-6/13/2020), and pandemic recovery (6/14/2020-10/10/2020). We examined weekly number of TTEs performed or interpreted by cardiology fellows during the study period, and compared these to the two previous academic years.

RESULTS: Weekly TTE volume declined by 54% during the pandemic, and increased by 99% during pandemic recovery, (p < 0.05). SE and TEE revealed similar trends. A strong correlation between weekly TTE volume and inpatient admissions was observed during the study period (rs=0.67, p < 0.05). Weekly fellow TTE scans declined by 78% during the pandemic, with a 380% increase during pandemic recovery (p < 0.05). Weekly fellow TTE interpretations declined by 56% during the pandemic, with a 76% increase during pandemic recovery (p < 0.05).

CONCLUSION: COVID restrictions between 3/15/2020- 6/14/2020 coincided with a marked decline in TTE, SE, and TEE volumes, with an increase similar to near pre-pandemic volumes during the pandemic recovery period. A similar decline with the onset of COVID restrictions, and increase to pre-restriction volumes thereafter was observed with fellow scans and interpretations, but total academic year fellow training volumes remained depressed. With the ongoing COVID-19 pandemic and rise of multiple variants, training programs may need to adjust fellows' clinical responsibilities so as to support achievement of echocardiography training certification.