Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

Performance of Computed Tomographic Angiography–Based Aortic Valve Area for Assessment of Aortic Stenosis

Background A total of 40% of patients with severe aortic stenosis (AS) have low‐gradient AS, raising uncertainty about AS severity. Aortic valve calcification, measured by computed tomography (CT), is guideline‐endorsed to aid in such cases. The performance of different CT‐derived aortic valve areas (AVAs) is less well studied. Methods and Results Consecutive adult patients with presumed moderate and severe AS based on echocardiography (AVA measured by continuity equation on echocardiography <1.5 cm2) who underwent cardiac CT were identified retrospectively. AVAs, measured by direct planimetry on CT (AVACT) and by a hybrid approach (AVA measured in a hybrid manner with echocardiography and CT [AVAHybrid]), were measured. Sex‐specific aortic valve calcification thresholds (≥1200 Agatston units in women and ≥2000 Agatston units in men) were applied to adjudicate severe or nonsevere AS. A total of 215 patients (38.0% women; mean±SD age, 78±8 years) were included: normal flow, 59.5%; and low flow, 40.5%. Among the different thresholds for AVACT and AVAHybrid, diagnostic performance was the best for AVACT <1.2 cm2 (sensitivity, 85%; specificity, 26%; and accuracy, 72%), with no significant difference by flow status. The percentage of patients with correctly classified AS severity (correctly classified severe AS+correctly classified moderate AS) was as follows; AVA measured by continuity equation on echocardiography <1.0 cm2, 77%; AVACT <1.2 cm2, 73%; AVACT <1.0 cm2, 58%; AVAHybrid <1.2 cm2, 59%; and AVAHybrid <1.0 cm2, 45%. AVACT cut points of 1.52 cm2 for normal flow and 1.56 cm2 for low flow, provided 95% specificity for excluding severe AS. Conclusions CT‐derived AVAs have poor discrimination for AS severity. Using an AVACT <1.2‐cm2 threshold to define severe AS can produce significant error. Larger AVACT thresholds improve specificity

Cardiac Magnetic Resonance Feature Tracking Global Longitudinal Strain and Prognosis After Heart Transplantation

Objectives: This study determined the long-term prognostic significance of GLS assessed using CMR-FT in a large cohort of heart transplant recipients. Background: In heart transplant recipients, global longitudinal strain (GLS) assessed using echocardiography has shown promise in the prediction of clinical outcomes. We hypothesized that CMR feature tracking (CMR-FT) GLS is independently associated with long-term outcomes in heart transplant recipients. Methods: In a cohort of consecutive heart transplant recipients who underwent routine CMR for clinical surveillance, CMR-FT GLS was calculated from 3 long-axis cine CMR images. Associations between GLS and a composite endpoint of death or major adverse cardiac events (MACE), including retransplantation, nonfatal myocardial infarction, coronary revascularization, and heart failure hospitalization, were investigated. Results: A total of 152 heart transplant recipients (age 54 ± 15 years; 29% women; 5.0 ± 5.4 years after heart transplantation) were included. The median GLS was&nbsp;-11.6% (interquartile range:&nbsp;-13.6% to&nbsp;-9.2%). Over a median follow-up of 2.6 years, 59 recipients reached the composite endpoint. On Kaplan-Meier analyses, recipients with GLS worse than the median had a higher estimated cumulative incidence of the composite endpoint compared with recipients with GLS better than the median (log rank p&nbsp;=&nbsp;0.004). On multivariate Cox proportional hazards regression, GLS was independently associated with the composite endpoint after adjustment for cardiac allograft vasculopathy, history of rejection, left ventricular ejection fraction (LVEF), right ventricular EF, and presence of myocardial fibrosis, with a hazard ratio of 1.15 for every 1% worsening in GLS (95% confidence interval: 1.06 to 1.24; p&nbsp;&lt;&nbsp;0.001). Similar results were seen in subgroups of recipients with LVEF &gt;50% and with no myocardial fibrosis. GLS provided incremental prognostic value over other variables in the multivariate model as determined by the log-likelihood chi-squared test. Conclusions: In a large cohort of heart transplant recipients, CMR-FT GLS was independently associated with the&nbsp;long-term risk of death or MACE

Safety and prognostic value of regadenoson stress cardiovascular magnetic resonance imaging in heart transplant recipients

Abstract Background There is a critical need for non-invasive methods to detect coronary allograft vasculopathy and to risk stratify heart transplant recipients. Vasodilator stress testing using cardiovascular magnetic resonance imaging (CMR) is a promising technique for this purpose. We aimed to evaluate the safety and the prognostic value of regadenoson stress CMR in heart transplant recipients. Methods To evaluate the safety, we assessed adverse effects in a retrospective matched cohort study of consecutive heart transplant recipients who underwent regadenoson stress CMR matched in a 2:1 ratio to age- and gender-matched non-heart transplant patients. To evaluate the prognostic value, we compared the outcomes of patients with abnormal vs. normal regadenoson stress CMRs using a composite endpoint of myocardial infarction, percutaneous intervention, cardiac hospitalization, retransplantation or death. Results For the safety analysis, 234 regadenoson stress CMR studies were included - 78 performed in 57 heart transplant recipients and 156 performed in non-heart transplant patients. Those in heart transplant recipients were performed at a median of 2.74 years after transplantation. Thirty-four (44%) CMR studies were performed in the first two years after heart transplantation. There were no differences in the rates of adverse effects between heart transplant recipients and non-heart transplant patients. To study the prognostic value of regadenoson stress CMRs, 20 heart transplant recipients with abnormal regadenoson stress CMRs were compared to 37 with normal regadenoson stress CMRs. An abnormal regadenoson stress CMR was associated with a significantly higher incidence of the composite endpoint compared with a normal regadenoson stress CMR (3-year cumulative incidence estimates of 32.1% vs. 12.7%, p = 0.034). Conclusions Regadenoson stress CMR is safe and well tolerated in heart transplant recipients, with no incidence of sinus node dysfunction or high-degree atrioventricular block, including in the first two years after heart transplantation. An abnormal regadenoson stress CMR identifies heart transplant recipients at a higher risk for major adverse cardiovascular events