iPSC microtissue gives clues to heart disease

Researchers at Leiden University Medical Center have developed a three cell type microtissue from human induced pluripotent stem cells (iPSCs) that increased the maturation of iPSC-derived heart muscle cells, and afforded the researchers new insights into how different heart cell types communicate in healthy and diseased heart tissue. Heart muscle cells, or cardiomyocytes, can be developed from iPSCs to a point, but such cells do not mature fully. The authors sought to help their development by co-culturing them with other cell types, which has improved the realism of cell cultures in organoid models. The team separately derived heart muscle cells, fibroblasts and endothelial cells, which allowed them to investigate the consequences of genetic mutations specifically in one cell type. They found that microtissues made from healthy heart muscle cells, but fibroblasts derived from iPSCs of patients with arrhythmogenic cardiomyopathy “strikingly recapitulated features of the disease,” the authors wrote. “Our [microtissue] model is thus a simple and versatile platform for modeling multicellular cardiac diseases that will facilitate industry and academic engagement in high-throughput molecular screening.” Their work appeared in the May 26, 2020, issue of Cell Stem Cell.

Two paths for helping patients with heart stents

There appears to be a better option than aspirin alone for patients who have had an angioplasty with a stent in terms of better health outcomes. That's according to a recent study by a team of cardiologists at the University of Alberta and Mazankowski Alberta Heart Institute, led by Kevin Bainey, an interventional cardiologist and associate professor. Their work builds on the COMPASS study that followed 27,400 people globally with stable coronary or peripheral artery disease. It showed that the combination of a small dose of the blood thinner rivaroxaban twice daily plus 100 mg of aspirin once daily was significantly better than only one or the other in preventing heart attacks, strokes and death. "There are a lot of patients with stable coronary disease who have stents in their heart arteries. Most commonly, the only blood thinner they are taking is aspirin," Bainey said. So, would a dual pathway prove better? To answer this question, the team focused on a subgroup of nearly 10,000 COMPASS participants who had undergone an angioplasty with a stent. Results showed that the treatment led to better health outcomes in that group, reducing heart attacks, strokes and deaths. "It didn't matter if a patient had a stent a year ago or 10 years ago; with this dual pathway strategy you still see an improvement in outcomes and, most importantly, an improvement in survival," he said. Health Canada has approved the dual-pathway treatment for use in patients with chronic coronary or peripheral disease. Bainey hopes his research will encourage more cardiologists and physicians to prescribe it to patients with or without a prior stent. The findings appeared March 17, 2020, in Circulation.

COVID-19 hits stroke patients

Findings that appear in the Journal of NeuroInterventional Surgery show ischemic stroke patients are arriving to hospitals and treatment centers an average of 160 minutes later during the COVID-19 pandemic vs. a similar time frame last year. This is affecting survival and recovery. Neurointerventionalists with the Get Ahead of Stroke campaign say that in the case of emergent large vessel occlusions, for example, up to 2 million brain cells die each minute. That can have a profound impact on patients. In addition, for every minute lost, there is an associated medical cost of $1,000 for short- and long-term care. That means a 160-minute delay leads to the loss of 320 million brain cells and $160,000 in additional medical costs. "When it comes to stroke treatment, every minute counts. My colleagues and I have been devastated to see patients arriving at the hospital too late for us to help them," said the study's lead author Clemens Schirmer, who is based at Geisinger Medical Center in Danville, Pa. "Our findings indicate a dire need for public education to address COVID-19 related fears to ensure people with stroke symptoms seek the lifesaving care they need without delay." Their findings appeared May 28, 2020.

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