Aging leads to increased cellular senescence and is associated with decreased potency of tissue‐specific stem/progenitor cells. Here, we have done an extensive analysis of cardiac progenitor cells (CPCs) isolated from human subjects with cardiovascular disease, aged 32–86 years. In aged subjects (>70 years old), over half of CPCs are senescent (p16INK4A, SA‐β‐gal, DNA damage γH2AX, telomere length, senescence‐associated secretory phenotype [SASP]), unable to replicate, differentiate, regenerate or restore cardiac function following transplantation into the infarcted heart. SASP factors secreted by senescent CPCs renders otherwise healthy CPCs to senescence. Elimination of senescent CPCs using senolytics abrogates the SASP and its debilitative effect in vitro. Global elimination of senescent cells in aged mice (INK‐ATTAC or wild‐type mice treated with D + Q senolytics) in vivo activates resident CPCs and increased the number of small Ki67‐, EdU‐positive cardiomyocytes. Therapeutic approaches that eliminate senescent cells may alleviate cardiac deterioration with aging and restore the regenerative capacity of the heart.

Aging leads to increased cellular senescence and is associated with decreased potency of tissue-specific stem/progenitor cells. Here we have done an extensive analysis of cardiac progenitor cells (CPCs) isolated from human subjects with cardiovascular disease (n=119), aged 32-86 years. In aged subjects (>74 years old) over half of CPCs are senescent (p16INK4A, SA-β-gal, DNA damage γH2AX, telomere length, Senescence-Associated Secretory Phenotype (SASP)), unable to replicate, differentiate, regenerate or restore cardiac function following transplantation into the infarcted heart. SASP factors secreted by senescent CPCs renders otherwise healthy CPCs to senescence. Elimination of senescent CPCs using senolytics abrogates the SASP and its debilitative effect in vitro. Global elimination of senescent cells in aged mice (INK-ATTAC or wildtype mice treated with D+Q senolytics) in vivo activates resident CPCs (0.23±0.06% vs. 0.01±0.01% vehicle; p<0.05) and increased the number of small, proliferating Ki67-, EdU-positive cardiomyocytes (0.25±0.07% vs. 0.03±0.03% vehicle; p<0.05). Therapeutic approaches that eliminate senescent cells may alleviate cardiac deterioration with aging and rejuvenate the regenerative capacity of the heart.

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The current evolving global pandemic caused by coronavirus disease‐2019 (COVID‐19) has dramatically impacted global health care systems, resulting in governments taking unprecedented measures to contain the spread of the infection, with adaptations by health care organizations. Research into understanding the pathophysiology behind this virus, to ascertain best medical management and treatment, has been accelerated to keep up with the rapidly evolving situation. There has been redeployment of medical and nursing staff to the frontlines and redistribution of health care resources. In addition, the cancellation of elective surgery and centralization of services to treat high‐risk surgical cases will all, undeniably, have an impact on current surgical training with possible future implications. We aim to explore the impact COVID‐19 is having on cardiac surgical training in the UK and what future implications this may have.

Key PointsQuestionIs transcatheter aortic valve implantation (TAVI) noninferior to surgical aortic valve replacement (surgery) in patients aged 70 years or older with severe, symptomatic aortic stenosis and moderately increased operative risk?FindingsIn this randomized clinical trial that included 913 patients at moderately increased operative risk due to age or comorbidity, all-cause mortality at 1 year was 4.6% with TAVI vs 6.6% with surgery, a difference that met the prespecified noninferiority margin of 5%.MeaningAmong patients aged 70 years or older with severe, symptomatic aortic stenosis and moderately increased operative risk, treatment with TAVI was noninferior to surgery with respect to all-cause mortality at 1 year.