Goldkorn, Ronen

Background Although endothelial function is a marker for cardiovascular risk, endothelial dysfunction assessment is not routinely used in daily clinical practice. A growing challenge has emerged in identifying patients prone to cardiovascular events. We aim to investigate whether abnormal endothelial function may be associated with adverse 5-year outcomes in patients presenting to a chest pain unit (CPU). Methods Following endothelial function testing using EndoPAT 2000 in 300 consecutive patients without a history of coronary artery disease, patients underwent coronary computerized tomographic angiography (CCTA) or single-photon emission computed tomography according to availability. Results Mean 10-year Framingham risk score (FRS) was 6.6 ± 5.9%; mean 10-year atherosclerotic cardiovascular disease (ASCVD) risk was 7.1 ± 7.2%; median reactive hyperemia index (RHI) as a measure of an endothelial function 2.0 and mean was 2.0 ± 0.4. During a 5-year follow-up, the 30 patients who developed major adverse cardiovascular events (MACE), including all-cause mortality, nonfatal myocardial infarction, hospitalization for heart failure or angina pectoris, stroke, coronary artery bypass grafting, and percutaneous coronary interventions, had higher 10-year FRS (9.6 ± 7.8 vs. 6.3 ± 5.6%; P = 0.032), higher 10-year ASCVD risk (10.4 ± 9.2 vs. 6.7 ± 6.9%; P = 0.042), lower baseline RHI (1.6 ± 0.5 vs. 2.1 ± 0.4; P < 0.001) and a greater degree of coronary atherosclerotic lesions (53 vs. 3%, P < 0.001) on CCTA compared with patients without MACE. Multivariate analysis demonstrated that RHI below the median was an independent predictor of 5-year MACE (odds ratio 5.567, 95% confidence interval 1.955–15.853; P = 0.001). Conclusion Our findings suggest that noninvasive endothelial function testing may contribute to clinical efficacy in triaging patients in the CPU and in predicting 5-year MACE. Clinical Trials.gov Identifier NCT01618123

Background Detecting significant coronary artery disease (CAD) in the general population is complex and relies on combined assessment of traditional CAD risk factors and noninvasive testing. We hypothesized that a CAD‐specific heart rate variability (HRV) algorithm can be used to improve detection of subclinical or early ischemia in patients without known CAD. Methods and Results Between 2014 and 2018 we prospectively enrolled 1043 patients with low to intermediate pretest probability for CAD who were screened for myocardial ischemia in tertiary medical centers in the United States and Israel. Patients underwent 1‐hour Holter testing, with immediate HRV analysis using the HeartTrends DyDx algorithm, followed by exercise stress echocardiography (n=612) or exercise myocardial perfusion imaging (n=431). The threshold for low HRV was identified using receiver operating characteristic analysis based on sensitivity and specificity. The primary end point was the presence of myocardial ischemia detected by exercise stress echocardiography or exercise myocardial perfusion imaging. The mean age of patients was 61 years and 38% were women. Myocardial ischemia was detected in 66 (6.3%) patients. After adjustment for CAD risk factors and exercise stress testing results, low HRV was independently associated with a significant 2‐fold increased likelihood for myocardial ischemia (odds ratio, 2.00; 95% CI, 1.41–2.89 [ P =0.01]). Adding HRV to traditional CAD risk factors significantly improved the pretest probability for myocardial ischemia. Conclusions Our data from a large prospective international clinical study show that short‐term HRV testing can be used as a novel digital‐health modality for enhanced risk assessment in low‐ to intermediate‐risk individuals without known CAD. Clinical Trial Registration URL: http://www.ClinicalTrials.gov . Unique identifiers: NCT01657006, NCT02201017).