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

Širdies adrenerginės inervacijos vaizdinimas širdies nepakankamumui prognozuoti

Summary of doctoral dissertatio

Cardiac adrenergic innervation imaging for prediction heart failure

Doctoral dissertatio

Ischemic Muscle Necrosis of Lower Extremities in Peripheral Arterial Disease: The Impact of 99mTc-MDP Scintigraphy on Patient Management

Background and objectives: The objective of this study was to assess the value of a whole-body bone scintigraphy using 99m technetium labelled-methyl diphosphonate (99mTc-MDP) for the diagnosis and the assessment of grades of muscle damage after prolonged acute or chronic obstruction of the main arteries in lower extremities. Material and Methods: Fifty consecutive patients were selected for the study. The patients’ condition had not improved after primary peripheral arterial reconstruction operation or limb amputation and after conservative treatment. The clinical suspicion was of arterial obstruction and muscle necrosis. All the patients underwent whole-body scintigraphy with 99mTc-MDP. Muscle necrosis was identified as an increased soft tissue uptake of 99mTc-MDP. Results: Forty-five patients had gross muscle necrosis detected on whole-body scintigraphy with 99mTc-MDP and were histologically confirmed after repeated surgery (necrectomy or amputation) or by muscle biopsy, if only fasciotomy was performed. The location and extent of muscle injury were assessed preoperatively and the findings were confirmed in all 45 patients. Twelve patients with clinically suspected minor muscle damage, which was confirmed as relatively minor muscle necrosis on 99mTc-MDP scintigraphy, were treated conservatively. The clinical outcome of all 50 patients was favorable. The 99mTc-MDP scintigraphy, in detection of muscular necrosis, demonstrated sensitivity, specificity, and accuracy of 97.3% (95% confidence interval (CI) 85.4 to 99.3%), 30.77% (95% confidence interval (CI) 9.09 to 61.43%), and 80% (95% confidence interval (CI) 66.28 to 89.97%), respectively. Conclusion: The 99mTc-MDP scintigraphy is a valuable tool in the detection of muscular necrosis. It is able to define location, extent, and grade of involvement. Therefore, it has a clinical impact in patient management, allowing clinicians to select adequate treatment policy and specify the scope of necrectomy.</jats:p

Ischemic muscle necrosis of lower extremities in peripheral arterial disease: the impact of 99mTc-MDP scintigraphy on patient management

Background and objectives: The objective of this study was to assess the value of a wholebody bone scintigraphy using 99m technetium labelled-methyl diphosphonate (99mTc-MDP) for the diagnosis and the assessment of grades of muscle damage after prolonged acute or chronic obstruction of the main arteries in lower extremities. Material and Methods: Fifty consecutive patients were selected for the study. The patients’ condition had not improved after primary peripheral arterial reconstruction operation or limb amputation and after conservative treatment. The clinical suspicion was of arterial obstruction and muscle necrosis. All the patients underwent whole-body scintigraphy with 99mTc-MDP. Muscle necrosis was identified as an increased soft tissue uptake of 99mTc-MDP. Results: Forty-five patients had gross muscle necrosis detected on whole-body scintigraphy with 99mTc-MDP and were histologically confirmed after repeated surgery (necrectomy or amputation) or by muscle biopsy, if only fasciotomy was performed. The location and extent of muscle injury were assessed preoperatively and the findings were confirmed in all 45 patients. Twelve patients with clinically suspected minor muscle damage, which was confirmed as relatively minor muscle necrosis on 99mTc-MDP scintigraphy, were treated conservatively. The clinical outcome of all 50 patients was favorable. The 99mTc-MDP scintigraphy, in detection of muscular necrosis, demonstrated sensitivity, specificity, and accuracy of 97.3% (95% confidence interval (CI) 85.4% to 99.3%), 30.77% (95% confidence interval (CI) 9.09% to 61.43%), and 80% (95% confidence interval (CI) 66.28% to 89.97%), respectively. Conclusion: The 99mTc-MDP scintigraphy is a valuable tool in the detection of muscular necrosis. It is able to define location, extent, and grade of involvement. [...]

Comparative Analysis of Cardiac SPECT Myocardial Perfusion Imaging: Full-Ring Solid-State Detectors Versus Dedicated Cardiac Fixed-Angle Gamma Camera

Background and Objectives: Single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) is a well-established technique for evaluating myocardial perfusion and function in patients with suspected or known coronary artery disease. While conventional dual-detector SPECT scanners have limitations in spatial resolution and photon detection sensitivity, recent advancements, including full-ring solid-state cadmium zinc telluride (CZT) detectors, offer enhanced image quality and improved diagnostic accuracy. This study aimed to compare the performance of Veriton-CT, a full-ring CZT SPECT system, with GE Discovery 530c, a dedicated cardiac fixed-angle gamma camera, in myocardial perfusion imaging and their correlation with coronary angiography findings. Materials and Methods: This was a prospective study that analyzed 21 patients who underwent MPI at the Department of Nuclear Medicine, Lithuanian University of Health Sciences, Kauno Klinikos. A one-day stress&ndash;rest protocol using 99mTc-Sestamibi was employed, with stress testing performed via bicycle ergometry or pharmacological induction. MPI was first conducted using GE Discovery 530c (GE Health Care, Boston, MA, USA), followed by imaging on Veriton-CT, which included low-dose CT for attenuation correction. The summed stress score (SSS), summed rest score (SRS), and summed difference score (SDS) were analyzed and compared between both imaging modalities. Coronary angiography results were retrospectively collected, and lesion-based analysis was performed to assess the correlation between imaging results and the presence of significant coronary artery stenosis (&ge;35% and &ge;70% narrowing). Image quality and the certainty of distinguishing the inferior myocardial wall from extracardiac structures were also evaluated by two independent researchers with differing levels of experience. Results: Among the 14 patients included in the final analysis, Veriton-CT was more likely to classify MPI scans as normal (64.3%) compared to GE Discovery 530c (28.6%). Additionally, Veriton-CT provided a better assessment of the right coronary artery (RCA) basin, showing greater agreement with coronary angiography findings than GE Discovery 530c, although the difference was not statistically significant. No significant differences in lesion overlap were observed for the left anterior descending artery (LAD) or left circumflex artery (LCx) basins. Furthermore, the image quality assessment revealed slightly better delineation of extracardiac structures using Veriton-CT (Spectrum Dynamics Medical, Caesarea, Israel), particularly when evaluated by an experienced researcher. However, no significant difference was observed when assessed by a less experienced observer. Conclusions: Our findings suggest that Veriton-CT, with its full-ring CZT detector system, may offer advantages over fixed-angle gamma cameras in improving image quality and reducing attenuation artifacts in MPI. Although the difference in correlations with coronary angiography findings was not statistically significant, Veriton-CT showed a trend toward better agreement, particularly in the RCA basin. These results indicate that full-ring SPECT imaging could improve the diagnostic accuracy of non-invasive MPI, potentially reducing the need for unnecessary invasive angiography. Further studies with larger patient cohorts are required to confirm these findings and evaluate the clinical impact of full-ring SPECT technology in myocardial perfusion imaging

Assessing Liver Fibrosis Using 2D-SWE Liver Ultrasound Elastography and Dynamic Liver Scintigraphy with 99mTc-mebrofenin: A Comparative Prospective Single-Center Study

Background and Objectives: Many quantitative imaging modalities are available that quantify chronic liver disease, although only a few of them are included in clinical guidelines. Many more imaging options are still competing to find their place in the area of diagnosing chronic liver disease. We report our first prospective single-center study evaluating different imaging modalities that stratify viral hepatitis-associated liver fibrosis in a treatment-naïve patient group. Materials and Methods: The aim of our study is to compare and to combine already employed 2D shear wave elastography (2D-SWE) with dynamic liver scintigraphy with 99mTc-mebrofenin in chronic viral hepatitis patients for the staging of liver fibrosis. Results: Seventy-two patients were enrolled in the study. We found that both 2D-SWE ultrasound imaging, with dynamic liver scintigraphy with 99mTc-mebrofenin are able to stratify CLD patients into different liver fibrosis categories based on histological examination findings. We did not find any statistically significant difference between these imaging options, which means that dynamic liver scintigraphy with 99mTc-mebrofenin is not an inferior imaging technique. A combination of these imaging modalities showed increased accuracy in the non-invasive staging of liver cirrhosis. Conclusions: Our study presents that 2D-SWE and dynamic liver scintigraphy with 99mTc-mebrofenin could be used for staging liver fibrosis, both in singular application and in a combined way, adding a potential supplementary value that represents different aspects of liver fibrosis in CLD.</jats:p

Quantitative Assessment of Liver Impairment in Chronic Viral Hepatitis with [99mTc]Tc-Mebrofenin: A Noninvasive Attempt to Stage Viral Hepatitis-Associated Liver Fibrosis

Background and objectives&mdash;Chronic viral hepatitis B and C infections are one of the leading causes of chronic liver impairment, resulting in liver fibrosis and liver cirrhosis. An early diagnosis with accurate liver fibrosis staging leads to a proper diagnosis, thus tailoring correct treatment. Both invasive and noninvasive techniques are used in the diagnosis and staging of chronic liver impairment. Those techniques include liver biopsy, multiple serological markers (as either single tests or combined panels), and imaging examinations, such as ultrasound or magnetic resonance elastography. Nuclear medicine probes may also be employed in staging liver fibrosis, although the literature scarcely reports this. The purpose of our study was to investigate whether a dynamic liver scintigraphy with [99mTc]Tc-mebrofenin has any value in staging or grading chronic liver damage. Materials and Methods&mdash;We prospectively enrolled patients with chronic viral hepatitis B and C infection referred for liver biopsy. All patient underwent dynamic liver scintigraphy with 99mTc-mebrofenin prior to liver biopsy. Dynamic liver scintigraphy was performed immediately after intravenous tracer injection for 30 min scanning time. Multiple scintigraphy parameters were calculated (whole liver lobe and focal area time to peak (TTP), 30 min to peak ratio (30/peak), whole lobe and focal area slope index in 350 s (slope_350). Liver biopsy took place shortly after imaging. Results&mdash;We found that many dynamic scintigraphic parameters are positively or negatively associated with different stages of liver fibrosis. The main parameters that showed most value are the ratio between 30 min and the peak of the dynamic curve (30/peak_dex (ratio)), and liver clearance corrected for body surface area and liver area (LCL_m2_dm2 (%/min/m2/dm2)). Conclusions&mdash;Our present study proves that conducting dynamic liver scintigraphies with [99mTc]Tc-mebrofenin has potential value in staging liver fibrosis. The benefits of this method, including whole liver imaging and direct imaging of the liver function, provide an advantage over presently used quantitative imaging modalities