Quyyumi, Arshed A.

Background: The gap between artificial intelligence-derived age (ECG-Age) and chronological age has been validated as a strong predictor of increased cardiovascular morbidity and mortality, independent of age, and is a potential biomarker of biological aging. Acute stress may cause real-time, transient changes in autonomic function via electrophysiological signals that, when repeated over time, may contribute to biological aging and represent mechanisms linking stress and Major Adverse Cardiovascular Events (MACE). We hypothesized that acute mental stress induced in a laboratory is associated with increased ECG and that this increase is associated with a higher risk of MACE among individuals with stable coronary heart disease (CHD). Methods: We pooled two prospective cohorts of participants with stable CHD from a university-based hospital network in Atlanta. Stress was induced using a standardized mental stress test (public speaking task) and measured 12-lead ECGs during rest, mental stress, and recovery periods. To measure ECG-age, we utilized a published algorithm using a neural network on >500,000 independent patients. The study endpoint was MACE including nonfatal myocardial infarction, hospitalization for heart failure, or cardiovascular death. The difference in ECG-Age between resting and acute mental stress was used to define the stress Age-Gap. Cox proportional hazard regression modeled the association of stress Age-Gap operationalized as tertiles adjusting for chronological age, sex, race, cardiovascular risk factors, and baseline Cohen perceived stress scale. Results: 442 participants in the total sample pool (38% women). Over a 5-year median follow-up, 95 participants (21%) experienced MACE. At rest, the mean chronologic age was 55.7±9.9 years, and ECG-Age was 57.1 ±10.7 years, with rest Age-Gap of 0. 9±9.6 (p=0.16). During stress, the stress Age-Gap of 1.95±9.8 (p<0.0001), while recovery Age-Gap was 1.1±10.3 (p=0.13). Those that demonstrated the largest ECG-Age positive change between rest and stress by ECG (top tertile) had a higher risk for MACE when compared to those with the lowest or negative ECG age change (bottom tertile), see Figure. Conclusion: Among patients with stable CHD, acute mental stress caused changes in biological age as measured by AI-ECG consistent with accelerated biological aging. Such changes were associated with MACE. These results uncover accelerated biological aging as a mechanism linking acute stress to CVD outcomes.

Background: Collateral blood flow, modulated by inflammation and arteriogenesis, alters ischemic injury in intracranial atherosclerosis. We investigated the potential link between several inflammatory and arteriogenic biomarkers with angiographic findings at enrollment in BIOSIS/SAMMPRIS. Methods: Baseline angiography and blood biomarkers of BIOSIS/SAMMPRIS, which included subjects with stroke or TIA due to 70-99% intracranial stenosis were analyzed. Collateral blood flow status at angiography was categorized by the combination of antegrade flow (TICI) and corresponding extent of collaterals (ASITN/SIR). Collateral status was analyzed with respect to blood progenitor cell markers (CD34) at baseline and inflammatory biomarkers (Plasminogen Activator Inhibitor-1 (PAI-1), E-selectin, high sensitivity C-reactive protein (hsCRP) and Lipoprotein-associated phospholipase A2 (Lp-PLA 2 ) activity and concentrations) at baseline, 30 days and 4 months. Results: 376 subjects (mean age 60.44 years SD 11; 149/376 (39.6%) women) enrolled in BIOSIS/SAMMPRIS had angiography of collaterals and biomarker data. Collateral perfusion was impaired in 71 (19%) and intermediate in 188 (50%), with robust collaterals in 117 (30%) subjects. Better collateral status was associated with younger age (p=0.001), male sex (p=0.029) and greater baseline physical activity (p=0.007). Baseline blood progenitor cell (CD34+) counts were unrelated to angiographic features at enrollment, whereas inflammatory Lp-PLA 2 activity was linked (p=0.059) with blood flow categories, and lower hsCRP (p=0.025) with better collaterals. Lp-PLA 2 activity was lowest in those with robust collaterals at 30 days (p=0.070) and 4 months (p=0.120). Those with robust collaterals had the greatest decrease in Lp-PLA 2 activity (p=0.021) and concentration (p=0.027) by 30 days, with a continued decline of Lp-PLA 2 activity (p=0.037) to 4 months. Disparate trends in inflammatory markers were seen in the medical and stenting arms. Conclusions: Inflammatory biomarkers are linked with collateral blood flow status in intracranial atherosclerosis. The impact of physical activity, medications and other therapeutic investigations may disclose important mechanisms to avert ischemia.

Background: Prior studies suggest an association between naturally high circulating levels of CD34+ cells (CD34) and better outcomes following ischemic events. Pts in the treatment arm of the PreSERVE-AMI study were infused with all CD34 yielded from their bone marrow harvest, resulting in pts with naturally higher CD34 cell counts being infused with a higher cell dose. To determine whether selection bias may have influenced results, we performed an analysis of the relationship between BM CD34 content and outcomes in PreSERVE-AMI. Methods: PreSERVE-AMI is a Phase 2, randomized, double-blind, placebo-controlled trial of autologous, BM derived CD34 (CLBS10) in pts with LV dysfunction (LVEF ≤48% by MRI) ≥4 days post-STEMI. All pts underwent mini BM harvest and were randomized 1:1 to intracoronary infusion of CD34 (minimum dose 10M±20% cells) or placebo (cell diluent). Primary safety endpoints included AEs, SAEs and MACE (CV mortality, HF hospitalization, reinfarction, revascularization). Secondary endpoints included LVEF change from baseline. Regression analyses were performed to assess the influence of BM CD34 content on outcomes. Results: 161 patients were randomized and received intracoronary infusion (Jan 2013-Dec 2014). Mean age was 57±10 and 82% were men. Mean follow-up time was 18 mo, and safety data are accruing. BM CD34 content was not associated with differences in baseline characteristics with the exception of diabetes prevalence being higher in those with higher BM CD34 count (p=0.03). In controls, regression analyses showed no association of BM CD34 content with rates of MACE (p=0.2), SAEs (p=0.4), or change in LVEF (p=0.9). However, in CD34 treated pts, there was a dose-dependent improvement in LV function (p=0.045) and dose-dependent trends in MACE and SAE reduction compared to controls. As previously reported SPECT perfusion improved to a similar degree in control and treated pts. Conclusions: These data suggest that intracoronary infusion of CD34 cells, rather than BM CD34 cell content, is responsible for the benefit observed in the CD34 treatment group. The finding of a dose-response relationship is an important advance for defining the CD34 as an active agent for tissue repair. Future studies will further define CD34 dosimetry.

Background: Microvascular dysfunction is known to play a key role in patients with angina and nonobstructive coronary artery disease. We investigated the impact of ranolazine among patients with angina and nonobstructive coronary artery disease. Methods: In this randomized, double-blinded, placebo-controlled pilot trial, 26 patients with angina once weekly or more, abnormal stress test, and nonobstructive coronary artery disease (<50% stenosis by angiography and fractional flow reserve >0.80) were randomized 1:1 to ranolazine or placebo for 12 weeks. Primary end point was ΔSeattle Angina Questionnaire (SAQ) angina frequency score. Baseline and 3 months follow-up SAQ, Duke Activity Status Index scores along with invasive fractional flow reserve, coronary flow reserve (CFR), hyperemic myocardial resistance, and cardiopulmonary exercise testing measurements were performed. Results: No significant differences in ΔSAQ angina frequency scores ( P =0.53) or Duke Activity Status Index ( P =0.76) were observed between ranolazine versus placebo, although patients on ranolazine had lesser improvement in SAQ physical limitation scores ( P =0.02) compared with placebo at 3 months. There were no significant differences in ΔCFR or Δhyperemic myocardial resistance between ranolazine and placebo groups. Patients treated with ranolazine, compared with placebo, had no significant improvement in maximum rate of oxygen consumption measured during incremental exercise (VO 2 max) and peak metabolic equivalents of task. Interestingly, in the ranolazine group, patients with baseline CFR<2.0 demonstrated greater gain in CFR compared with those with baseline CFR≥2.0 ( P =0.02). Conclusions: Ranolazine did not demonstrate improvement in SAQ angina frequency score, invasive microvascular function, or peak metabolic equivalent compared with placebo at 3 months. Registration: URL: https://www.clinicaltrials.gov . Unique identifier: NCT02147067.