scholarly journals Lactate Stress Testing in 155 Patients with Mitochondriopathy

Author(s):  
Josef Finsterer ◽  
Erika Milvay

Objective:Few data are available about the diagnostic yield of the lactate stress test (LST) in a large group of patients with mitochondriopathy (MCP).Methods:Serum lactate was determined once before, three times during, and once after a 15-minute, constant 30W workload on a bicycle in 62 controls, aged 17 to 84 years, 155 patients with MCP, aged 17 to 87 years, and 31 patients with neurological disorders other than MCP.Results:Lactate's upper reference limits at rest, 5, 10, 15 minutes after starting, and 15 minutes after finishing the exercise were 2.0, 2.1, 2.1, 2.1 and 1.8 mmol/l respectively. The test was regarded abnormal if more than two of the five lactate values exceeded the cut-off levels. Among the 103 patients with abnormal LST, 64 (62 %) had normal resting lactate. The sensitivity of the test was 67% and the specificity 94%.Conclusion:The LST proved to have a high sensitivity and specificity in the detection of patients with MCP, being thus a simple but powerful tool to assess the impaired oxidative metabolism in MCP patients.

Circulation ◽  
2020 ◽  
Vol 142 (13) ◽  
pp. 1249-1260 ◽  
Author(s):  
Michela Casella ◽  
Antonio Dello Russo ◽  
Marco Bergonti ◽  
Valentina Catto ◽  
Edoardo Conte ◽  
...  

Background: Electroanatomic voltage mapping (EVM) is a promising modality for guiding endomyocardial biopsies (EMBs). However, few data support its feasibility and safety. We now report the largest cohort of patients undergoing EVM-guided EMBs to show its diagnostic yield and to compare it with a cardiac magnetic resonance (CMR)–guided approach. Methods: We included 162 consecutive patients undergoing EMB at our institution from 2010 to 2019. EMB was performed in pathological areas identified at EVM and CMR. CMR and EVM sensitivity and specificity regarding the identification of pathological substrates of myocardium were evaluated according to EMB results. Results: Preoperative CMR showed late gadolinium enhancement in 70% of the patients, whereas EVM identified areas of low voltage in 61%. Right (73%), left (19%), or both ventricles (8%) underwent sampling. EVM proved to have sensitivity similar to CMR (74% versus 77%), with specificity being 70% and 47%, respectively. In 12 patients with EMB-proven cardiomyopathy, EVM identified pathological areas that had been undetected at CMR evaluation. Sensitivity of pooled EVM and CMR was as high as 95%. EMB analysis allowed us to reach a new diagnosis, different from the suspected clinical diagnosis, in 39% of patients. The complications rate was low, mostly related to vascular access, with no patients requiring urgent management. Conclusions: EVM proved to be a promising tool for targeted EMB because of its sensitivity and specificity for identification of myocardial pathological substrates. EVM was demonstrated to have accuracy similar to CMR. EVM and CMR together conferred a positive predictive value of 89% on EMB.


Author(s):  
Mouin Abdallah ◽  
John Spertus ◽  
Nestor Mercado ◽  
Brahmajee Nallamothu ◽  
Kevin Kennedy ◽  
...  

Background: Many patients undergoing elective percutaneous coronary intervention (PCI) do not have prior stress testing. It is unknown if these patients have more severe angina or obstructive coronary artery disease (CAD), whereby proceeding directly to PCI would represent sound clinical judgment and efficient use of resources. Methods: We identified elective PCIs performed between 1/1/09 - 3/31/11 in the NCDR CathPCI Registry ® and assessed for differences in angina (CCS class) and severity of CAD in those with and without pre-procedural stress testing. To further understand whether proceeding to PCI without prior stress testing could be justified because of a high pre-test probability for obstructive CAD (e.g., >70% stenosis in an epicardial coronary artery), we evaluated cardiac catheterizations performed within the registry during the same period to assess the diagnostic yield of obstructive CAD in patients with and without prior stress testing. Results: Of 246,629 elective PCIs, 89,084 (36.1%) were performed without prior stress testing. A substantial proportion of both groups undergoing PCI were asymptomatic (no stress test group: 28.9% vs. stress test group: 30.7%), with only a modest difference in the frequency of CCS class III/IV angina (16.2% vs. 11.9%; Table). No meaningful differences in the frequency of proximal LAD (29.7 % vs. 29.9%), left main (5.6% vs. 7.2%) or 3-vessel coronary artery disease (21.1% vs. 19.5%) were observed in the 2 PCI groups. Moreover, the diagnostic yield for obstructive CAD on cardiac catheterization for patients without prior stress testing (n=462,611) was 35.4%, as compared with 58.0%, 38.8%, and 24.1% for those with severe, moderate, and mild ischemia, on pre-procedural stress testing. Conclusion: For elective PCI, the current practice of proceeding to coronary angiography and PCI without prior stress testing does not identify higher risk coronary anatomy or more symptomatic patients and may not improve diagnostic yield.


2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
J T Neumann ◽  
A Gossling ◽  
N Soerensen ◽  
T Zeller ◽  
S Blankenberg ◽  
...  

Abstract Objective In patients with suspected coronary artery disease (CAD) and intermediate pretest probability non-invasive stress-testing is recommended in current guidelines. However, sensitivity and specificity of these tests are limited. We aimed to investigate the additional diagnostic value of high-sensitivity troponin I concentrations measured before and after stress-testing. Methods We included patients undergoing non-invasive stress-testing in a prospective cohort study. All patients provided written informed consent, were at least 18 years old and underwent either stress-echocardiography, stress-MRI or myocardial perfusion scintigraphy. Baseline parameters were collected by questionnaire and chart review. Blood samples were collected before, and one hour after the stress-test. Troponin was measured using the Abbott Architect high-sensitivity troponin I (hs-TnI) assay. The diagnostic performance to predict a pathological stress-test was evaluated by calculation of the area under the ROC curve (AUC) using baseline hs-TnI concentrations and the absolute change after one hour. An optimal cutoff was determined by maximization of the Youden Index. Univariate odds ratios (OR) were calculated to identify predictors for a pathological stress-test. Additionally ORs for the optimal hs-TnI cutoff were calculated in a multivarite regression with adjustment for baseline variables. Results In total 391 patients with a median age of 70 years were included. 66.8% were males, 83.4% had prevalent hypertension, 55.9% had dyslipidemia and 55.4% had a prior history of CAD. A pathological stress-test was reported in 21.5% and these patients had a higher cardiovascular risk profile, compared to patients with a non-pathological stress-test. The baseline hs-TnI concentrations were 4.7 ng/L in the overall population, 4.2 ng/L in patients with a non-pathological stress-test and 8.4 ng/L (p<0.001) in patients with a pathological stress-test. There was no significant hs-TnI changes one hour after stress-testing. The AUC for the baseline hs-TnI was 0.65 and the optimal cutoff was determined at 7.7 ng/L. Most cardiovascular risk factors were predictors for a pathological stress-test. The OR for an elevated hs-TnI above the optimized cutoff was 3.34 (95% CI 2.03, 5.52). In a multivariate model a baseline hs-TnI above 7.7 ng/L showed an OR of 2.07 (95% CI 1.04, 4.12; p-value 0.039) Conclusion In patients undergoing non-invasive stress-testing, hs-TnI concentrations did not significantly change one hour after exercise. However, an elevated troponin concentration is an independent predictor for a pathological stress-test.


Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Stephanie Hong ◽  
Getu Teressa

Introduction: Noninvasive diagnostic testing serves as gatekeepers to invasive cardiac catheterization. Computed tomography coronary angiogram (CTCA) has been shown to have high sensitivity and negative predictive value in the diagnosis of coronary artery disease (CAD). However, the temporal trend of CTCA compared to functional tests and the differential downstream impact on cardiac catheterization is unknown. Objective: This study aimed to investigate the temporal trend of the use in CTCA for the evaluation of patients with chest pain and how it compares to the temporal trend of stress testing. The secondary aim was to investigate the temporal pattern in the cardiac catheterization rate and how it varies between CTCA and stress testing. Methods: We performed a retrospective review of 65,686 patients who presented to a large academic medical center with chest pain between 2012 and 2019. We identified those who received CTCA testing or stress testing as the initial diagnostic testing for diagnosing suspected CAD and collected data on downstream cardiac catheterization. We calculated the testing rate per 1000 for each year. Results: Of the patient who received noninvasive imaging (n=18,843), more CTCA was performed (18.6%) compared to stress test (10.1%). After an initial upward trend in CCTA use and a downward trend in stress test use between 2012 and 2014, the trend reversed for both modalities after 2015. The rate of cardiac catheterization increased after 2014, mirroring an increase in stress test utilization. Patients who had stress test first have increased odds of undergoing catheterization compared to those who had CTCA first, even after adjusting for risk factors. However, compared to CTCA, stress test shows a relative decline in the odds of catheterization (Relative adjusted Odd Ratio: 5.6 in 2012 down to 2.8 in 2019) Conclusion: In this large single-center study of chest pain patients, stress-testing leads to increased odds of cardiac catheterization compared to CCTA. However, the relative odds of undergoing catheterization following stress testing show a declining trend.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Camila Lema ◽  
Mireia Andrés ◽  
Santiago Aguadé-Bruix ◽  
Marta Consegal ◽  
Antonio Rodriguez-Sinovas ◽  
...  

Abstract Cardiovascular diseases are the leading cause of death worldwide. Changes in lifestyle and/or pharmacological treatment are able to reduce the burden of coronary artery diseases (CAD) and early diagnosis is crucial for the timely and optimal management of the disease. Stress testing is a good method to measure the burden of CAD but it is time consuming and pharmacological testing may not fully mimic exercise test. The objectives of the present project were to characterize the metabolic profile of the population undergoing pharmacological and exercise stress testing to evaluate possible differences between them, and to assess the capacity of 1H NMR spectroscopy to predict positive stress testing. Pattern recognition was applied to 1H NMR spectra from serum of patients undergoing stress test and metabolites were quantified. The effects of the stress test, confounding variables and the ability to predict ischemia were evaluated using OPLS-DA. There was an increase in lactate and alanine concentrations in post-test samples in patients undergoing exercise test, but not in those submitted to pharmacological testing. However, when considering only pharmacological patients, those with a positive test result, showed increased serum lactate, that was masked by the much larger amount of lactate associated to exercise testing. In conclusion, we have established that pharmacological stress test does not reproduce the dynamic changes observed in exercise stress. Although there is promising evidence suggesting that 1H NMR based metabolomics could predict stress test results, further studies with much larger populations will be required in order to obtain a definitive answer.


2010 ◽  
Vol 48 (08) ◽  
Author(s):  
A Rosenthal ◽  
H Köppen ◽  
R Musikowski ◽  
R Schwanitz ◽  
J Behrendt ◽  
...  

2010 ◽  
pp. 61-81 ◽  
Author(s):  
O. Solntsev ◽  
A. Pestova ◽  
M. Mamonov

The article analyzes factors that affect growth of the share of non-performing loans in the loan portfolio of Russian banks and proposes approaches for this share forecasting on the basis of dynamics of macroeconomic indicators. It also deals with methodological issues of remote stress-test of lending agencies. Using the results of conducted stress-test of Russian banks the authors assess their perspective capital needs in 2010 and estimate the share of government assistance in capital injections. Furthermore, the authors define the scale of vulnerable banks groups in the Russian banking sector.


2019 ◽  
Vol 26 (11) ◽  
pp. 1946-1959 ◽  
Author(s):  
Le Minh Tu Phan ◽  
Lemma Teshome Tufa ◽  
Hwa-Jung Kim ◽  
Jaebeom Lee ◽  
Tae Jung Park

Background:Tuberculosis (TB), one of the leading causes of death worldwide, is difficult to diagnose based only on signs and symptoms. Methods for TB detection are continuously being researched to design novel effective clinical tools for the diagnosis of TB.Objective:This article reviews the methods to diagnose TB at the latent and active stages and to recognize prospective TB diagnostic methods based on nanomaterials.Methods:The current methods for TB diagnosis were reviewed by evaluating their advantages and disadvantages. Furthermore, the trends in TB detection using nanomaterials were discussed regarding their performance capacity for clinical diagnostic applications.Results:Current methods such as microscopy, culture, and tuberculin skin test are still being employed to diagnose TB, however, a highly sensitive point of care tool without false results is still needed. The utilization of nanomaterials to detect the specific TB biomarkers with high sensitivity and specificity can provide a possible strategy to rapidly diagnose TB. Although it is challenging for nanodiagnostic platforms to be assessed in clinical trials, active TB diagnosis using nanomaterials is highly expected to achieve clinical significance for regular application. In addition, aspects and future directions in developing the high-efficiency tools to diagnose active TB using advanced nanomaterials are expounded.Conclusion:This review suggests that nanomaterials have high potential as rapid, costeffective tools to enhance the diagnostic sensitivity and specificity for the accurate diagnosis, treatment, and prevention of TB. Hence, portable nanobiosensors can be alternative effective tests to be exploited globally after clinical trial execution.


Author(s):  
Hala T. Salem ◽  
Eman A.S. Sabek

Aim and Objective: To estimate the relationship between Coronary Calcium Scoring (CCS)and presence of different degrees of obstructive coronary artery disease (CAD) to avoid unnecessary examinations and hence unnecessary radiation exposure and contrast injection. Background: Coronary Calcium Scoring (CCS) is a test uses x-ray equipment to produce pictures of the coronary arteries to determine the degree of its narrowing by the build-up of calcified plaques. Despite the lack of definitive data linking ionizing radiation with cancer, the American Heart Association supports widely that practitioners of Computed tomography Coronary Angiography (CTCA) should keep “patient radiation doses as low as reasonably achievable but consistent with obtaining the desired medical information”. Methods: Data obtained from 275 CTCA examinations were reviewed. Radiation effective doses were estimated for both CCS and CTCA, measures to keep it as low as possible were presented, CCS and Framingham risk estimate were compared to the final results of CTCA to detect sensitivity and specificity of each one in detecting obstructive lesions. Results: CCS is a strong discriminator for obstructive CAD and can with high sensitivity and specificity and correlates well with the degree of obstruction even more than Framingham risk estimate which has high sensitivity and low specificity. Conclusion: CCS helps reducing the effective radiation dose if properly evaluated to skip unnecessary CTCA if obstructive lesions was unlikely, and as a test does not use contrast material, harmful effect on the kidney will be avoided as most of coronary atherosclerotic patients have renal problems.


2021 ◽  
Author(s):  
Birgid Schömig-Markiefka ◽  
Alexey Pryalukhin ◽  
Wolfgang Hulla ◽  
Andrey Bychkov ◽  
Junya Fukuoka ◽  
...  

AbstractDigital pathology provides a possibility for computational analysis of histological slides and automatization of routine pathological tasks. Histological slides are very heterogeneous concerning staining, sections’ thickness, and artifacts arising during tissue processing, cutting, staining, and digitization. In this study, we digitally reproduce major types of artifacts. Using six datasets from four different institutions digitized by different scanner systems, we systematically explore artifacts’ influence on the accuracy of the pre-trained, validated, deep learning-based model for prostate cancer detection in histological slides. We provide evidence that any histological artifact dependent on severity can lead to a substantial loss in model performance. Strategies for the prevention of diagnostic model accuracy losses in the context of artifacts are warranted. Stress-testing of diagnostic models using synthetically generated artifacts might be an essential step during clinical validation of deep learning-based algorithms.


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