Myocardial Perfusion Abnormalities in Patients with Hereditary Hypertrophic Cardiomyopathy: A Study of Three Cases and Review of the Literature

Introduction: Hypertrophic cardiomyopathy (HCM) belongs to the very heterogeneous group of cardiomyopathies. This study aimed to study myocardial perfusion abnormalities on scintigraphy and assess the risk of sudden death from ventricular arrhythmia in hereditary sarcomeric HCM. Patients and Methods: This is a retrospective and prospective descriptive study over 18 months (January 01, 2021, to July 31, 2022) on the records of patients over 18 with the diagnosis of hypertrophic sarcomeric cardiomyopathy with or without ventricular rhythm disorders and who have undergone myocardial scintigraphy. Results: Three patients were included. The average age of our patients was 66 years old. Dyspnea is the primary symptomatology found in our patients. One patient presented with syncope and unsustained ventricular tachycardia. His risk score for sudden death from ESC at five years is estimated at 6.45%, and the patient received an ICD in primary prevention. The average sudden death risk score of our patients was 3.78%. The mean LV wall thickness was 20 mm. The mean maximum left intraventricular gradient was 39 mmHg. Myocardial fibrosis was present in all our patients. Myocardial scintigraphy was normal in all cases. Conclusion: Hypertrophic cardiomyopathy is a very heterogeneous group of cardiomyopathies. The rhythmic risk is multifactorial and constitutes a significant prognostic factor.

Comparison between multiple logistic regression and machine learning methods in prediction of abnormal thallium scans in type 2 diabetes

BACKGROUND The prevalence of type 2 diabetes(T2D)has been increasing dramatically in recent decades,and 47.5%of T2D patients will die of cardiovascular disease.Thallium-201 myocardial perfusion scan(MPS)is a precise and noninvasive method to detect coronary artery disease(CAD).Most previous studies used traditional logistic regression(LGR)to evaluate the risks for abnormal CAD.Rapidly developing machine learning(Mach-L)techniques could potentially outperform LGR in capturing non-linear relationships.AIM To aims were:(1)Compare the accuracy of Mach-L methods and LGR;and(2)Found the most important factors for abnormal TMPS.METHODS 556 T2D were enrolled in the study(287 men and 269 women).Demographic and biochemistry data were used as independent variables and the sum of stressed score derived from MPS scan was the dependent variable.Subjects with a MPS score≥9 were defined as abnormal.In addition to traditional LGR,classification and regression tree(CART),random forest,Naïve Bayes,and eXtreme gradient boosting were also applied.Sensitivity,specificity,accuracy and area under the receiver operation curve were used to evaluate the respective accuracy of LGR and Mach-L methods.RESULTS Except for CART,the other Mach-L methods outperformed LGR,with gender,body mass index,age,low-density lipoprotein cholesterol,glycated hemoglobin and smoking emerging as the most important factors to predict abnormal MPS.CONCLUSION Four Mach-L methods are found to outperform LGR in predicting abnormal TMPS in Chinese T2D,with the most important risk factors being gender,body mass index,age,low-density lipoprotein cholesterol,glycated hemoglobin and smoking.

Cardiac Amyloidosis: A Case Report of Seven Patients

Introduction: Cardiac amyloidosis is a rare and under-diagnosed disease. The objective of this study was to collect cases of cardiac amyloidosis in patients hospitalized in the cardiology department of the Centre Hospitalier Intercommunal Alençon-Mamers (CHICAM). Patients and Methods: This was a retrospective descriptive study of the records of patients diagnosed with cardiac amyloidosis. The study took place in the cardiology department of the CHICAM over 12 months (from January 1, 2020 to December 31, 2020). We included the files of patients in whom the diagnosis of cardiac amyloidosis was confirmed on the basis of clinical, echocardiographic, biological, scintigraphic and cardiac MRI evidence. Results: Seven patients were included. The mean age was 86.71 years. Six men for one woman. Most of the patients were in heart failure. There was one case of periorbital ecchymosis. Troponinemia was increased in three patients, NTproBNP was always high with a mean of 1000 ng/L. Cardiac echography showed a hyperbright septum in four cases, concentric hypertrophy of the left ventricle with a mean interventricular septum in diastole of 13.85 mm. Six cases were senile transthyretin amyloidosis (TTR), one case was mutated transthyretin amyloidosis (TTRm). Two cases of death were noted. Conclusion: Cardiac amyloidosis has a poor prognosis due to delayed diagnosis.

Long-term prognostic value of analysis of sympathetic drive by myocardial 123I-metaiodobenzylganidine scintigraphy in chronic heart failure

Background The over increase of sympathetic drive in chronic heart failure （CHF） is with main responsibility for the deterioration and mortality of the disease.Myocardial 123I-metaiodobenzylganidine （MIBG） scintigraphy is a non-invasive convenient method to assess sympathetic dysfunction in patients with CHF.The aim of the study was to detect if sympathetic antidrive analysed through myocardial MIBG scintigraphy plays a crucial role in long-term prognosis in CHF.Methods Sixty-four enrolled patients underwent myocardial MIBG scintigraphy, and their plasma concentration of brain natriuretic peptide （BNP）, myocardial contractile reserve （MCR）, rest left ventricular ejection fraction （rest LVEF）and New York Heart Association （NYHA） function class were assessed.They were separated into groups according to median of above parameters.Endpoint was cardiac death and it was recorded in each group during average 54 months＇ follow-up.Results At the end of follow-up, group with lower ratio of heart/mediastinum （H/M） had more death events （P=0.001）,and its BNP level was higher and MCR level was lower （P=0.003 and 0.001, respectively）; but its rest LVEF and NYHA function class were not significantly different.H/M, MCR and BNP correlated closely with death （P=0.000, 0.000 and 0.001, respectively）.Among the three indicators the death risk ratio （RR） of H/M was 4.66, more than MCR and BNP （1.88 and 2.56, respectively）.However, rest LVEF and NYHA function class did not correlate with death （P=0.652 and 0.384, respectively）.The group with lower H/M and MCR, higher BNP had much more death than that with higher H/M and MCR, lower BNP, the RR being 12.8.Conclusions Myocardial MIBG scintigraphy is a long-term prognostic marker in CHF.BNP, MCR are also excellent predictors of long-term prognosis in CHF, but not stronger than myocardial MIBG scintigraphy.If the three indicators were joined together, the prediction would become most powerful.Rest LVEF and NYHA have no significance in long-term prediction of CHF.

Reduced Heart Rate Response during Drug-Induced Stress Is Related to the Severity of Perfusion Defect

Introduction: During the pharmacological stress test with dipyridamole, a normal hemodynamic response is slightly reduced blood pressure and raised heart rate (HR). However, sometimes the HR response is reduced. This study investigated the relationship between the HR response during the dipyridamole stress test and the severity of the perfusion defects using Thallium 201 myocardial perfusion imaging. Methods: We enrolled 50 patients undergoing dipyridamole stress at the nuclear cardiology Lab, Main University Hospital of Alexandria. Standard dipyridamole protocol (infusion over 4 min) and standard thallium 201 protocol (2 min after dipyridamole infusion) were followed. If the heart rate (HR) ratio (peak HR/rest HR) was 1.20 or less, it was considered a reduced response. Total perfusion defect (TPD), summed stress score (SSS), summed rest score (SRS), and summed difference score (SDS) for myocardial perfusion were calculated. Patients with reduced HR response and normal HR responses were compared and independent predictors of reduced HR response were determined. Results: About 56% of patients had reduced HR response;which included a high number of patients with a history of dyslipidemia and diabetes mellitus. The reduced HR response group showed lower SSS, SRS. The analysis showed that the independent predictors of reduced HR response were rest HR, SSS, and diabetes mellitus. Conclusions: Reduction in the HR response during the dipyridamole-induced stress test is related to the severity of perfusion defect, diabetes mellitus, and Dyslipidemia.

Imaging biomarkers in Parkinson’s disease and Parkinsonian syndromes:current and emerging concepts

Two centuries ago in 1817,James Parkinson provided the first medical description of Parkinson’s disease,later refined by Jean-Martin Charcot in the mid-to-late 19th century to include the atypical parkinsonian variants(also termed,Parkinson-plus syndromes).Today,Parkinson’s disease represents the second most common neurodegenerative disorder with an estimated global prevalence of over 10 million.Conversely,atypical parkinsonian syndromes encompass a group of relatively heterogeneous disorders that may share some clinical features with Parkinson’s disease,but are uncommon distinct clinicopathological diseases.Decades of scientific advancements have vastly improved our understanding of these disorders,including improvements in in vivo imaging for biomarker identification.Multimodal imaging for the visualization of structural and functional brain changes is especially important,as it allows a‘window’into the underlying pathophysiological abnormalities.In this article,we first present an overview of the cardinal clinical and neuropathological features of,1)synucleinopathies:Parkinson’s disease and other Lewy body spectrum disorders,as well as multiple system atrophy,and 2)tauopathies:progressive supranuclear palsy,and corticobasal degeneration.A comprehensive presentation of wellestablished and emerging imaging biomarkers for each disorder are then discussed.Biomarkers for the following imaging modalities are reviewed:1)structural magnetic resonance imaging(MRI)using T1,T2,and susceptibilityweighted sequences for volumetric and voxel-based morphometric analyses,as well as MRI derived visual signatures,2)diffusion tensor MRI for the assessment of white matter tract injury and microstructural integrity,3)proton magnetic resonance spectroscopy for quantifying proton-containing brain metabolites,4)single photon emission computed tomography for the evaluation of nigrostriatal integrity(as assessed by presynaptic dopamine transporters and postsynaptic dopamine D2 receptors),and cerebral perfusion,5)positron emission tomography for gauging nigrostriatal functions,glucose metabolism,amyloid and tau molecular imaging,as well as neuroinflammation,6)myocardial scintigraphy for dysautonomia,and 7)transcranial sonography for measuring substantia nigra and lentiform nucleus echogenicity.Imaging biomarkers,using the‘multimodal approach’,may aid in making early,accurate and objective diagnostic decisions,highlight neuroanatomical and pathophysiological mechanisms,as well as assist in evaluating disease progression and therapeutic responses to drugs in clinical trials.