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Sarcoidosis is a multi-system inflammatory disease characterized by the development of inflammation and noncaseating granulomas that can involve nearly every organ system, with a predilection for the pulmonary system. Cardiac involvement... more
Sarcoidosis is a multi-system inflammatory disease characterized by the development of inflammation and noncaseating granulomas that can involve nearly every organ system, with a predilection for the pulmonary system. Cardiac involvement of sarcoidosis (CS) occurs in up to 70% of cases, and accounts for a significant share of sarcoid-related mortality. The clinical presentation of CS can range from absence of symptoms to conduction abnormalities, heart failure, arrhythmias, valvular disease, and sudden cardiac death. Given the significant morbidity and mortality associated with CS, timely diagnosis is important. Traditional imaging modalities and histologic evaluation by endomyocardial biopsy often provide a low diagnostic yield. Cardiac positron emission tomography (PET) has emerged as a leading advanced imaging modality for the diagnosis and management of CS. This review article will summarize several aspects of the current use of PET in CS, including indications for use, patient ...
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The above position statement originally published containing errors in the author metadata; specifically, the Expert Content Reviewers-Andrew Einstein, Raymond Russell and James R. Corbett-were tagged as full authors of the paper. The... more
The above position statement originally published containing errors in the author metadata; specifically, the Expert Content Reviewers-Andrew Einstein, Raymond Russell and James R. Corbett-were tagged as full authors of the paper. The article metadata has now been corrected to remove Drs. Einstein, Russell and Corbett from the author line, and the PubMed record has been updated accordingly.
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The current diagnosis of infective endocarditis (IE) is based on the modified Duke criteria, which has approximately 80% sensitivity for the diagnosis of native valve endocarditis (NVE), with lower sensitivity for the diagnosis of... more
The current diagnosis of infective endocarditis (IE) is based on the modified Duke criteria, which has approximately 80% sensitivity for the diagnosis of native valve endocarditis (NVE), with lower sensitivity for the diagnosis of prosthetic valve endocarditis (PVE) and culture-negative endocarditis. There is preliminary evidence that 18F-FDG PET/CT is an adjunctive diagnostic test with high accuracy reported in small studies to date. We therefore performed a meta-analysis of studies evaluating the use of PET/CT in the diagnosis of IE to establish a more precise estimate of accuracy. PubMed, Embase, Cochrane library, CINAHL, Web of Knowledge, and www.clinicaltrials.gov were searched from January 1990 to April 2017 for studies evaluating the accuracy of PET/CT for the evaluation of possible IE. We identified 13 studies involving 537 patients that were included in the meta-analysis. The pooled sensitivity of PET/CT for diagnosis of IE was 76.8% (95% CI 71.8-81.4%; Q = 39.9, P < 0.0...
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Background: The diagnostic yield of combined cardiopulmonary exercise testing (CPET) and myocardial perfusion imaging (MPI) has received limited study. Methods: We included consecutive patients who underwent combined CPET-MPI at a single... more
Background: The diagnostic yield of combined cardiopulmonary exercise testing (CPET) and myocardial perfusion imaging (MPI) has received limited study. Methods: We included consecutive patients who underwent combined CPET-MPI at a single tertiary referral center. An abnormal CPET test was defined
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Radionuclide imaging provides both established and emerging diagnostic and prognostic tools to assist clinicians in the management of patients with ischemic cardiomyopathy, cardiac sarcoidosis, and cardiac amyloidosis. This review... more
Radionuclide imaging provides both established and emerging diagnostic and prognostic tools to assist clinicians in the management of patients with ischemic cardiomyopathy, cardiac sarcoidosis, and cardiac amyloidosis. This review highlights the underlying pathophysiology of each entity and associated diagnostic and clinical challenges, and describes the available radionuclide imaging techniques. Specific protocols, advantages and disadvantages, comparison with other noninvasive imaging modalities, and discussion of the evolving role of hybrid imaging are also included.
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The diagnostic yield of combined cardiopulmonary exercise testing (CPET) and myocardial perfusion imaging (MPI) in patients referred for stress testing has received limited study. We evaluated consecutive patients who underwent combined... more
The diagnostic yield of combined cardiopulmonary exercise testing (CPET) and myocardial perfusion imaging (MPI) in patients referred for stress testing has received limited study. We evaluated consecutive patients who underwent combined CPET-MPI at a single tertiary referral center between 2011 and 2015. An abnormal CPET was defined as any of the following: reduced oxygen consumption, cardiac output impairment, or pulmonary impairment. Normal MPI was defined as the absence of resting or stress perfusion defect. The primary study outcome was change in clinical decision-making after CPET-MPI including management of pulmonary disease, management of deconditioning, heart failure management, and referral for cardiac catheterization. Outcomes of patients with normal and abnormal MPI were presented based on the specific CPET abnormality. 415 patients were included in the study. Of the 269 patients that had normal MPI, 206 (77%) had abnormal CPET. Patients with abnormal CPET and normal MPI,...
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Research Interests: Magnetic Resonance Imaging, MRI, Risk assessment, Positron Emission Tomography, Medicine, and 15 morePET, Heart Failure, Humans, Female, Male, Diagnostic Imaging, Aged, Middle Aged, Risk Assessment, Sensitivity and Specificity, LVEF, Randomized Controlled Trials as Topic, Myocardial Ischemia, Cardiovascular medicine and haematology, and Coronary Artery Bypass
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Research Interests: Magnetic Resonance Imaging, Medicine, Humans, Hemodynamics, Animals, and 15 moreMale, Technique, Clinical Sciences, European, Middle Aged, Single Photon Emission Computed Tomography, Myocardial Infarction, Swine, Positron, Radiopharmaceuticals, X ray Computed Tomography, Heart Ventricles, Radioisotope, Case Control Studies, and Myocardial Ischemia
Research Interests: Positron Emission Tomography, Medicine, Humans, Blood Glucose, Insulin, and 15 moreGlucose Metabolism, Male, Heart, Body Mass Index, Clinical Sciences, Middle Aged, Myocardium, Blood Flow, Coronary Circulation, Glucose Uptake, Healthy Subjects, Blood Flow Velocity, Patient selection, Myocardial Blood Flow, and Paediatrics and reproductive medicine
Clustering of classical cardiovascular risk factors is insufficient to account for the excess coronary artery disease (CAD) of patients with diabetes, and chronic hyperglycemia and insulin resistance (IR) are obvious culprits. Whole-body... more
Clustering of classical cardiovascular risk factors is insufficient to account for the excess coronary artery disease (CAD) of patients with diabetes, and chronic hyperglycemia and insulin resistance (IR) are obvious culprits. Whole-body and skeletal muscle IR is characteristic of patients with type 2 diabetes, but whether it extends to the normally contracting cardiac muscle is controversial. We investigated whether type 2 diabetes is associated with myocardial IR independent of CAD in a case-control series (n = 55) of male nondiabetic and diabetic (type 2 and type 1) patients with or without angiographically documented CAD. Baseline blood flow (15O-water) and insulin-stimulated glucose uptake (18F-fluoro-deoxyglucose) during euglycemic (5.6 mmol/l), physiological hyperinsulinemia (40 mU · min−1 · m−2 insulin clamp) were measured by positron emission tomography in skeletal muscle and normally contracting myocardium. Skeletal muscle glucose uptake was reduced in association with bot...
Research Interests: Cardiology, Diabetes, Medicine, Insulin Resistance, Complication, and 15 moreHumans, Internal Medicine, Hyperglycemia, Insulin, Diabetes mellitus, Female, Male, Association, Aged, Middle Aged, Adult, Coronary Circulation, Coronary Artery Disease, Case Control Studies, and Medical and Health Sciences
BACKGROUND Previous studies suggested the presence of myocardial ischemia in symptomatic patients with hypertrophic cardiomyopathy. Positron emission tomography, a technique that can identify metabolic consequences of ischemia in coronary... more
BACKGROUND Previous studies suggested the presence of myocardial ischemia in symptomatic patients with hypertrophic cardiomyopathy. Positron emission tomography, a technique that can identify metabolic consequences of ischemia in coronary artery disease, permits the noninvasive measurements of regional myocardial blood flow and glucose metabolism. This new quantitative imaging approach should therefore be suitable for detecting a possible enhancement of glucose utilization in myocardium of patients with hypertrophic cardiomyopathy and thus may help to elucidate the pathomechanism of ischemia in this disease. METHODS AND RESULTS In 13 symptomatic patients with hypertrophic cardiomyopathy, myocardial blood flow and glucose utilization were measured with intravenous N-13-ammonia and F-18 deoxyglucose at rest and, in four patients, again during supine bicycle exercise. At rest, blood flow was significantly lower in hypertrophied than in normal myocardium (0.78 +/- 0.19 versus 0.99 +/- 0...
Research Interests: Cardiology, Aging, Medicine, Electrocardiography, Echocardiography, and 15 moreHumans, Internal Medicine, Blood Glucose, Glucose Metabolism, Female, Male, Clinical Sciences, Aged, Adult, Blood Flow, Circulation, Coronary Circulation, Hypertrophic Cardiomyopathy, Glucose Uptake, and Cardiovascular medicine and haematology
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Obstructive sleep apnea (OSA) is associated with adverse cardiovascular outcomes, including myocardial infarction and stroke. Atherosclerosis is a key mechanism for these cardiovascular events. Recent cross-sectional studies showed the... more
Obstructive sleep apnea (OSA) is associated with adverse cardiovascular outcomes, including myocardial infarction and stroke. Atherosclerosis is a key mechanism for these cardiovascular events. Recent cross-sectional studies showed the presence of early signs of atherosclerosis in patients with OSA who were free of comorbidities. To determine the impact of treatment with continuous positive airway pressure (CPAP) on atherosclerosis. We randomly assigned 24 patients with severe OSA (age, 46 +/- 6 yr) who were free of comorbidities to receive no treatment (control, n = 12) or CPAP (n = 12) for 4 months. Carotid intima-media thickness, arterial stiffness (evaluated by pulse-wave velocity), carotid diameter, 24-hour blood pressure monitoring, C-reactive protein, and catecholamines were determined at baseline and after 4 months. At baseline, all measurements were similar in both groups and did not change in the control group after 4 months. In contrast, a significant decrease occurred in carotid intima-media thickness (707 +/- 105 vs. 645 +/- 95 microm, P = 0.04), pulse-wave velocity (10.4 +/- 1.0 vs. 9.3 +/- 0.9 m/s, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001), C-reactive protein (3.7 +/- 1.8 vs. 2.0 +/- 1.2 mg/L, P = 0.001), and catecholamines (365 +/- 125 vs. 205 +/- 51 ng/ml, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001) after 4 months of CPAP. Carotid diameter did not change significantly. Regarding the whole group, changes in carotid intima-media thickness were correlated with changes in catecholamines (r = 0.41, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05). Changes in pulse-wave velocity were correlated with changes in C-reactive protein (r = 0.58, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01) and catecholamines (r = 0.54, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01). The treatment of OSA significantly improves early signs of atherosclerosis, supporting the concept that OSA is an independent risk factor for atherosclerosis. Clinical trial registered with www.clinicaltrials.gov (NCT 00400543).
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Research Interests: Medicine, Electrocardiography, Humans, Hypertension, MPI, and 12 moreBlood Pressure, Female, Male, Aged, Prevalence, Middle Aged, Single Photon Emission Computed Tomography, Public health systems and services research, Retrospective Studies, Coronary Artery Disease, Exercise Test, and Cardiovascular medicine and haematology
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Using X-ray CT or magnetic resonance imaging (MRI), fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) studies were performed in 28 patients with parotid lesions. All lesions except two showed higher accumulation of... more
Using X-ray CT or magnetic resonance imaging (MRI), fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) studies were performed in 28 patients with parotid lesions. All lesions except two showed higher accumulation of FDG than normal parotid gland. High accumulation was found in all of 5 carcinomas, all of 6 Warthin's tumors, and 8 of 12 pleomorphic adenomas, with standardized uptake values (SUVs) over 3.0. The mean SUVs of carcinomas, Warthin's tumors, and pleomorphic adenomas were 5.92 +/- 2.05, 7.03 +/- 2.49, and 4.07 +/- 1.55, respectively. On the other hand, all 5 inflammatory lesions demonstrated low accumulation, with mean SUVs of 1.66 +/- 0.89. It is thus difficult to differentiate malignant from benign parotid lesions by SUV on FDG-PET.
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Research Interests: Medicine and Sarcoidosis
1Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota; 2Division of Cardiology, Department of Medicine, University of Ottawa Heart Institute, Ottawa, Canada; 3Department of Diagnostic Radiology and Nuclear Medicine,... more
1Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota; 2Division of Cardiology, Department of Medicine, University of Ottawa Heart Institute, Ottawa, Canada; 3Department of Diagnostic Radiology and Nuclear Medicine, University of Maryland School of Medicine, Baltimore, Maryland; 4Division of Nuclear Medicine, Brigham and Women’s Hospital, Boston, Massachusetts; 5Section of Cardiovascular Medicine, Yale University, New Haven, Connecticut; 6Division of Cardiovascular Medicine, University of Michigan, Ann Arbor, Michigan; 7School of Medicine, Johns Hopkins University, Baltimore, Maryland; 8Department of Cardiovascular Medicine, Mayo Clinic, Jacksonville, Florida; 9Division of Cardiology, University of Chicago Medicine, Chicago, Illinois; 10Division of Pulmonary Medicine, University of Michigan, Ann Arbor, Michigan; 11Department of Radiology and Nuclear Medicine, Duke University, Durham, North Carolina; and 12Department of Radiology, Mallinckrodt Institute of Radiolo...
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Myocardial viability assessment is typically reserved for patients with coronary artery disease and significant left ventricular dysfunction. In this setting, there is myocardial adaptation to an altered physiological state that is... more
Myocardial viability assessment is typically reserved for patients with coronary artery disease and significant left ventricular dysfunction. In this setting, there is myocardial adaptation to an altered physiological state that is potentially reversible. Imaging can characterize different parameters of cardiac function; however, despite previously published appraisals of different imaging modalities, there is still uncertainty regarding the role of these tests in clinical practice. The purpose of this review is to reflect on the physiological basis of myocardial viability, discuss the imaging tests available that characterize myocardial viability, and summarize the current published reports on the use of these tests in clinical practice.
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Myocarditis is a recognized but underdiagnosed cause of cardiomyopathy due to its wide clinical spectrum and nonspecific presentation. Accurate diagnosis is important because 25% of patients with acute myocarditis develop cardiomyopathy,... more
Myocarditis is a recognized but underdiagnosed cause of cardiomyopathy due to its wide clinical spectrum and nonspecific presentation. Accurate diagnosis is important because 25% of patients with acute myocarditis develop cardiomyopathy, and of those, approximately 5% per year require heart transplantation or die. Current guidelines for the recognition and treatment of the inflammatory cardiomyopathies are limited. The gold standard for diagnosis, endomyocardial biopsy, has low sensitivity, and thus, multimodality imaging of inflammation plays a crucial role in defining the cardiac abnormalities and in assisting with diagnosis and management. The literature on inflammatory cardiomyopathies is limited to small studies of selected populations due to the diverse etiologies and inherent difficulties in definitive diagnosis. This review focuses on the current and projected use of various imaging modalities, including echocardiography, cardiac magnetic resonance, and nuclear imaging to be...
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To examine the impact of time to thrombolytic treatment on multiple acute outcome variables in a single trial of thrombolysis in acute myocardial infarction. Mortality and reinfarction rate were measured in 2770 patients with acute... more
To examine the impact of time to thrombolytic treatment on multiple acute outcome variables in a single trial of thrombolysis in acute myocardial infarction. Mortality and reinfarction rate were measured in 2770 patients with acute myocardial infarction who received thrombolysis within 12 hours in CORE, an international, dose ranging trial of poloxamer 188. Tc-99m sestamibi infarct size and radionuclide angiographic ejection fraction substudies included 1099 and 1074 patients, respectively. Time to thrombolysis, subgrouped by intervals (< 2, 2-4, > or = 4-6, and > or = 6 hours), was significantly associated with infarct size (median 15.0%, 18.5%, 22.0%, 18.5% of left ventricle; p = 0.033), mean (SD) ejection fraction (51.5 (12.0)%, 48. 3 (13.9)%, 48.2 (13.3)%, 48.2 (15.0)%; p = 0.006), 35 day mortality (5.7%, 7.1%, 7.9%, 12.5%; p = 0.0004), six month mortality (7.3%, 8. 6%, 10.4%, 15.5%; p < 0.0001), and 35 day reinfarction rate (6.1%, 3. 2%, 4.0%, 0.9%; p = 0.0001). In ...
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The Bypass Angioplasty Revascularization Investigation trial demonstrated that symptomatic diabetics with multivessel coronary artery disease had a survival advantage with initial coronary artery bypass grafting (CABG) versus percutaneous... more
The Bypass Angioplasty Revascularization Investigation trial demonstrated that symptomatic diabetics with multivessel coronary artery disease had a survival advantage with initial coronary artery bypass grafting (CABG) versus percutaneous coronary intervention (PCI). No published study has examined different treatments and outcome in asymptomatic diabetics. This study group consisted of 826 asymptomatic diabetics (age 62+/-12 years; 76% men) without known coronary artery disease who had abnormal myocardial perfusion during stress single photon emission computed tomography (SPECT). SPECT images were classified as low-, intermediate-, and high-risk. Early revascularization (CABG or PCI < or =4 months after SPECT) was performed in 76 patients. Survival (follow-up, 5.3+/-3.3 years) was compared in patients treated with CABG, PCI, or medical therapy. Revascularization (CABG or PCI) was performed in 54 of 261 patients with high-risk scans and was independently associated with improved ...
Research Interests: Risk, Survival Analysis, Mortality, Humans, Female, and 16 moreMale, Clinical Sciences, Aged, Middle Aged, Coronary Angiography, Single Photon Emission Computed Tomography, Coronary heart disease, Public health systems and services research, Retrospective Studies, Prognosis, Circulation, Coronary artery bypass surgery, Type 2 Diabetes Mellitus, Exercise Test, Proportional Hazards Models, and Life tables
Research Interests: Algorithms, Cardiology, Risk, MRI, Treatment Outcome, and 14 morePositron Emission Tomography, PET, CAD, Humans, Myocardial Revascularization, Left Ventricular Dysfunction, Diagnostic Imaging, HF, Single Photon Emission Computed Tomography, Public health systems and services research, Cardiomyopathies, Ejection Fraction, LVEF, and Myocardial Ischemia
This study attempted to determine the relation between infarct size after acute myocardial infarction and subsequent left ventricular remodeling using precise clinical measurements. Animal studies have demonstrated that the degree of left... more
This study attempted to determine the relation between infarct size after acute myocardial infarction and subsequent left ventricular remodeling using precise clinical measurements. Animal studies have demonstrated that the degree of left ventricular remodeling after myocardial infarction is linearly related to infarct size. Clinical studies have not clearly replicated these results because of imprecise measurements and failure to adjust for patency of the infarct-related artery. Infarct size was measured from technetium-99m (Tc-99m) sestamibi perfusion images in 14 patients (12 with an anterior, 2 with an inferior infarction) by a threshold method previously described and expressed as percent of the left ventricle (32 +/- 17% left ventricle [mean +/- SD], range 6% to 58%). Absolute end-systolic volume, end-diastolic volume and ejection fraction were determined by electron beam computed tomographic images performed at discharge and at 6 weeks, 6 months and 1 year after myocardial infarction. All patients had documented infarct-related artery patency after reperfusion therapy. At hospital discharge, there was no correlation between infarct size and end-systolic and end-diastolic volumes or ejection fraction. There was significant left ventricular dilation in the study group over the next year. As remodeling progressed, there was closer correlation between infarct size and ejection fraction and end-systolic volume measures (infarct size vs. end-systolic volume, from r = 0.43 at discharge to r = 0.80 at 1 year; infarct size vs. ejection fraction, from r = -0.39 at discharge to r = -0.84 at 1 year). There was a strong inverse correlation between infarct size at discharge and subsequent changes over the next year in end-systolic volume (r = 0.63, p = 0.02) and ejection fraction (r = -0.66, p = 0.01). Infarct size as measured by Tc-99m sestamibi at hospital discharge after an index infarction is predictive of subsequent change in left ventricular volume and function in the year after myocardial infarction. Patients with a large infarct demonstrated the greatest degree of dilation in the setting of patency of the infarct-related artery.