Blankstein, Ron

BACKGROUND: Although the prognostic utility of positron emission tomography (PET) myocardial flow reserve (MFR) is well established, emerging data suggest that reduced subendocardial flows also predict adverse outcomes. However, the incremental value of subendocardial MFR (MFR SE ) beyond transmural MFR (MFR TM ) remains unclear. METHODS: We studied patients in a multicenter PET registry with normal perfusion on stress/rest Rb-82 PET, excluding those with a previous history of coronary artery bypass surgery, heart transplantation, or left ventricular ejection fraction <40%. The optimal MFR SE cutoff for predicting major adverse cardiovascular events (MACEs; death, myocardial infarction [MI], revascularization, or heart failure [HF] hospitalization) was determined using Youden’s index. Patients were stratified into 3 groups: concordant-normal (MFR TM ≥2.0; MFR SE ≥2.1), discordant (low-MFR SE , normal MFR TM ), and abnormal MFR TM . Clinical outcomes were compared by MFR groups. RESULTS: Among 6603 patients (normal N=4103; discordant N=885; abnormal N=1615) the mean age was 66.3±12.4 years, and 54% were women. Compared with the concordant-normal group, patients with discordant low-MFR SE were older and more likely to have hypertension, diabetes, peripheral artery disease, and previous percutaneous coronary intervention. The median MFR TM for normal, discordant, and abnormal groups were 2.86, 2.15, and 1.72, respectively. Over a median follow-up of 4.9 years, 1661 MACE events occurred. Discordant low-MFR SE patients had a higher risk of MACE (hazard ratio [HR], 1.41; 95% CI, 1.22–1.64) and all-cause mortality (HR, 1.36; 95% CI, 1.14–1.61) compared with concordant-normal patients. The discordant group had an intermediate absolute risk of MACE, with an adjusted annualized event rate of 5.79% (95% CI, 5.10–6.49) compared with 3.99% (95% CI, 3.67–4.30; P <0.001) in the concordant-normal group and 8.35% (95% CI, 7.71–9.00; P <0.001) in the abnormal MFR TM group. CONCLUSIONS: Subendocardial MFR reveals clinically meaningful risk heterogeneity among patients with preserved transmural flow reserve, helping refine risk stratification beyond traditional PET metrics.

Innovations in cardiac imaging have fundamentally advanced the understanding and treatment of cardiovascular disease. These advances in noninvasive cardiac imaging have also expanded the role of the cardiac imager and dramatically increased the demand for imagers who are cross-trained in multiple modalities. However, we hypothesize that there is significant variation in the availability of cardiac imaging expertise and a disparity in the adoption of advanced imaging technologies across the United States. To evaluate this, we have brought together the leaders of cardiovascular imaging societies, imaging trainees, as well as collaborated with national imaging accreditation commissions and imaging certification boards to assess the state of cardiac imaging and the diversity of the imaging workforce in the United States. Aggregate data confirm the presence of critical gaps, such as limited access to imaging and imaging expertise in rural communities, as well as disparities in the imaging workforce, notably among women and underrepresented minorities. Based on these results, we have proposed solutions to promote and maintain a robust and diverse community of cardiac imagers and improve equity and accessibility for cardiac imaging technologies.

Abstract Introduction Sarcoidosis is a multisystem disorder characterized by an autoimmune response to an unidentified antigen in genetically susceptible persons. Despite clinically detectable cardiac manifestations of sarcoidosis occurring in approximately 5% of patients, recent studies have revealed cardiac involvement to be at 25% in patients with the disease, highlighting the fact that cardiac involvement in sarcoidosis is much more common than was once thought to be. Purpose With cardiac involvement in sarcoidosis being increasingly recognized due to the availability of advanced cardiac imaging, large scale data regarding in-hospital mortality and clinical outcomes of patients admitted with cardiac sarcoidosis (CS) is lacking. Our study aimed to fill this knowledge gap by analyzing demographics and in-hospital outcomes of a large cohort of patients admitted with CS across the United States (US). Methods We analyzed data from the national inpatient sample (NIS) database between October 2015 to December 2018 to identify patients who had been admitted with primary and secondary diagnoses of CS. The NIS is an administrative database sponsored by the Agency for Healthcare Research and Quality consisting of data from 46 participating states, representing more than 95% of the US population and providing nationwide estimates of over 35 million hospitalizations annually. The NIS uses de-identified hospital discharges as samples and hence no additional ethical committee approval was required. International Classification of Diseases, 10th Revision, Clinical Modification (ICD-10-CM) code D86.85 was used to identify hospitalizations with CS in patients aged 18 years or older. SAS 9.4 (SAS Institute, Inc, Cary, NC) was used for statistical analyses. Results A total of 4275 patients were included in the analysis. A higher proportion of patients with CS were females (62.43% vs. 37.57%). Hypertension was the most common comorbidity (43.99%), followed by hyperlipidemia (39.21%) and chronic kidney disease (26.95%). All-cause in-hospital mortality was 2.57%. Atrial fibrillation (AF) was the most common arrhythmia (28.12%), followed by ventricular tachycardia (VT) (22.52%). About 16% of CS patients underwent implantable cardioverter-defibrillator (ICD) implantation during hospital stay. About 42% of patients had concurrent heart failure, out of whom 33.84% had heart failure with reduced ejection fraction (HFrEF). Mean length of hospital stay was 5 days (3–8 days), and the mean cost of hospitalization was $14,177 ($7,121–35,993). Conclusion Given the low prevalence of CS, most of the available studies have been retrospective in nature, based on small sample sizes. Despite being retrospective and cross-sectional, our study has the advantage of being based on a nationally representative sample population, providing key formation on the demographics and in-hospital outcomes of patients with CS. Funding Acknowledgement Type of funding sources: None.

Cardiac sarcoidosis is a component of an often multiorgan granulomatous disease of still uncertain cause. It is being recognized with increasing frequency, mainly as the result of heightened awareness and new diagnostic tests, specifically cardiac magnetic resonance imaging and 18 F-fluorodeoxyglucose positron emission tomography scans. The purpose of this case-based review is to highlight the potentially life-saving importance of making the early diagnosis of cardiac sarcoidosis using these new tools and to provide a framework for the optimal care of patients with this disease. We will review disease mechanisms as currently understood, associated arrhythmias including conduction abnormalities, and atrial and ventricular tachyarrhythmias, guideline-directed diagnostic criteria, screening of patients with extracardiac sarcoidosis, and the use of pacemakers and defibrillators in this setting. Treatment options, including those related to heart failure, and those which may help clarify disease mechanisms are included.