American Heart Association Identifies the Year's Top Cardiovascular and Stroke Research

The American Heart Association recently released its annual list of the top 10 advances in heart disease and stroke research, identifying “resuscitation, cell regeneration, a new high blood pressure treatment and developments in devices for treating stroke” as being among “the key scientific findings that make up this year’s top cardiovascular and stroke research.”

Here are several of the studies identified by the AHA:

Duration of Resuscitation Efforts and Survival after In-Hospital Cardiac Arrest: An Observational Study

Published in The Lancet in October 2012, the authors of this study concluded that “Duration of resuscitation attempts varies between hospitals. Although we cannot define an optimum duration for resuscitation attempts on the basis of these observational data, our findings suggest that efforts to systematically increase the duration of resuscitation could improve survival in this high-risk population.

Heart Repair by Reprogramming Non-Myocytes with Cardiac Transcription Factors

Published in Nature in May 2012, the authors wrote that “four transcription factors, GATA4, HAND2, MEF2C and TBX5, can cooperatively reprogram adult mouse tail-tip and cardiac fibroblasts into beating cardiac-like myocytes in vitro. Forced expression of these factors in dividing non-cardiomyocytes in mice reprograms these cells into functional cardiac-like myocytes, improves cardiac function and reduces adverse ventricular remodelling following myocardial infarction. Our results suggest a strategy for cardiac repair through reprogramming fibroblasts resident in the heart with cardiogenic transcription factors or other molecules.”

In Vivo Reprogramming of Murine Cardiac Fibroblasts into Induced Cardiomyocytes

Published in Nature in April 2012, the authors of this article demonstrated that “resident non-myocytes in the murine heart can be reprogrammed into cardiomyocyte-like cells in vivo by local delivery of GMT after coronary ligation. Induced cardiomyocytes became binucleate, assembled sarcomeres and had cardiomyocyte-like gene expression. Analysis of single cells revealed ventricular cardiomyocyte-like action potentials, beating upon electrical stimulation, and evidence of electrical coupling. In vivo delivery of GMT decreased infarct size and modestly attenuated cardiac dysfunction up to 3 months after coronary ligation. Delivery of the pro-angiogenic and fibroblast-activating peptide, thymosin β4, along with GMT, resulted in further improvements in scar area and cardiac function. These findings demonstrate that cardiac fibroblasts can be reprogrammed into cardiomyocyte-like cells in their native environment for potential regenerative purposes.”

Intracoronary cardiosphere-derived cells for heart regeneration after myocardial infarction (CADUCEUS)

Published in The Lancet in February 2012, this study looked at the effects of treating patients with myocardial infarction (with left ventricular ejection fraction rate of 25-45%) with either cardiosphere-derived cells (CDCs) or standard care. Patients treated with CDCs also had autologous cells grown from endomyocardial biopsy specimens infused into the infarct-related artery 6 weeks to three months post myocardial infarction. The authors reported that six months post-treatment, no patients in either treatment group had died, developed cardiac tumors, or major adverse cardiac events. Patients treated with CDCs showed reductions in scar mass, increases in viable heart mass and regional contractility, and regional systolic wall thickening. The authors reported that changes in end-diastolic volume, end-systolic volume, and left ventricular ejection fraction did not differ between groups. In their discussion of these results, the authors wrote that “intracoronary infusion of autologous CDCs after myocardial infarction is safe, warranting the expansion of such therapy to phase 2 study. The unprecedented increases we noted in viable myocardium, which are consistent with therapeutic regeneration, merit further assessment of clinical outcomes.”

Strategies for Multivessel Revascularization in Patients with Diabetes

Published in November 2012 in NEJM, these results from the FREEDOM trial revealed that “for patients with diabetes and advanced coronary artery disease, CABG was superior to PCI in that it significantly reduced rates of death and myocardial infarction, with a higher rate of stroke.”

Effects of Renal Sympathetic Denervation on Heart Rate and Atrioventricular Conduction in Patients with Resistant Hypertension

Published in August 2012 in the International Journal of Cardiology, this study showed that “renal sympathetic denervation reduced heart rate and the PR interval as indicators of cardiac autonomic activity.” The AHA identified three additional studies that produced intriguing results on the use of renal denervation to lower resistant hypertension, including “Catheter-Based Renal Sympathetic Denervation for Resistant Hypertension Durability of Blood Pressure Reduction Out to 24 Months,” published in Hypertension, which reported that prolonged renal denervation for up to two years “appears to be a potentially useful option for patients with refractory hypertension with an expectation of persistent lowering of BP postprocedure.”

Go here to access the complete AHA list of the top cardiovascular and stroke research, complete with commentary from AHA experts.