Research Spotlight

Posted April 15th 2019

Understanding Social Media: Opportunities for Cardiovascular Medicine.

John P. Erwin III M.D.

John P. Erwin III M.D.

Parwani, P., A. D. Choi, J. Lopez-Mattei, S. Raza, T. Chen, A. Narang, E. D. Michos, J. P. Erwin, 3rd, M. A. Mamas and M. Gulati (2019). “Understanding Social Media: Opportunities for Cardiovascular Medicine.” J Am Coll Cardiol 73(9): 1089-1093.

Full text of this article.

Cardiology professionals have used social media platforms such as Twitter to gain exposure to new research, network with experts, share opinions, and engage in scientific debates. The power of social media to communicate openly, with wide-reaching access worldwide, and at a rate faster than ever before makes it a formidable force and voice. However, evolving individual and institutional use has resulted in uncertainty for all parties on how to optimally advance this newer digital frontier. Thus, the purpose of this paper is to: 1) introduce the basics of social media usage (with the focus on Twitter); 2) provide perspective on best social media practices in academic and clinical cardiovascular medicine; and 3) present a vision for social media and the future of cardiovascular medicine.


Posted April 15th 2019

What Have We Learned From Randomized Controlled Trials of Catheter Ablation for Atrial Fibrillation in Patients With Chronic Heart Failure?

Milton Packer M.D.

Milton Packer M.D.

Packer, M. (2019). “What Have We Learned From Randomized Controlled Trials of Catheter Ablation for Atrial Fibrillation in Patients With Chronic Heart Failure?” Circ Arrhythm Electrophysiol 12(4): e007222.

Full text of this article.

Six trials have evaluated the effects of catheter ablation for atrial fibrillation (AF) in chronic heart failure (HF) (Table). Four compared catheter ablation to medical therapy directed at rate-control. These studies primarily enrolled patients with long-standing AF, and the control groups received atrioventricular nodal blocking drugs. In contrast, 2 trials compared catheter ablation to medical therapy primarily directed at rhythm control. These studies generally enrolled patients with paroxysmal or nonpermanent AF, and the control groups received membrane-active antiarrhythmic drugs . . . The totality of evidence suggests that catheter ablation for AF may have benefits on EF and functional capacity in chronic HF. However, the trials have been small and largely focused on patients with minimal or mild HF and only modest impairment of left ventricle function. In patients with meaningful degrees of HF and low EF, little efficacy has been observed, and the complication rate has been high. Because of the sparse number of events, the large number of patients with excluded or missing data, the lack of balance at randomization, and the use of comparator groups who were treated with cardiotoxic antiarrhythmic drugs to achieve rhythm control, it is not possible to suggest that a benefit of catheter ablation on morbidity and mortality has been demonstrated. Although the results of the 6 randomized trials of catheter ablation have been combined in numerous meta-analyses, summary estimates cannot overcome the inherent limitations of the component trials. Importantly, the available evidence from the 6 trials was not persuasive to the writers of the most recent guideline, which provided its weakest possible positive recommendation for the use of catheter ablation in patients with AF and chronic HF. . . Therefore, additional randomized controlled trials are needed to understand the range of potential responses to this procedure. (Excerpt from text, p. 1, 2-3; no abstract available.)


Posted April 15th 2019

Electrophysiological interventions in the treatment of chronic heart failure: a comparison of the strength of evidence supporting cardiac resynchronization for electrical conduction delay and catheter ablation for atrial fibrillation.

Milton Packer M.D.

Milton Packer M.D.

Packer, M. (2019). “Electrophysiological interventions in the treatment of chronic heart failure: a comparison of the strength of evidence supporting cardiac resynchronization for electrical conduction delay and catheter ablation for atrial fibrillation.” Eur J Heart Fail 21(4): 398-401.

Full text of this article.

In patients with a meaningful electrical conduction delay, the evidentiary support for the benefits of cardiac resynchronization is robust and strikingly consistent and is based on a large number and broad range of patients (n ≅ 10 000) enrolled in definitely‐powered trials. Many of these were specifically designed to evaluate the effects of treatment on morbidity and mortality, and they demonstrated meaningful reductions in the risk of death and hospitalizations for heart failure. In contrast, in patients with atrial fibrillation, the available trials of catheter ablation are small and have reported only sparse data. Reports of favourable effects on exercise tolerance and quality of life are difficult to interpret because of the open‐label design of the studies; changes in ejection fraction have been assessed by unreliable methods and have been inconsistent; and the reported decreases in morbidity and mortality have been observed in trials that had significant methodological limitations and/or used potentially cardiotoxic membrane‐active agents as a comparator. In addition, it is noteworthy that cardiac resynchronization follows a standardized approach, whereas the technique for catheter ablation varies considerably by physician. If catheter ablation is to be adopted as an appropriate therapy for large numbers of patients with chronic heart failure, it is important to develop a persuasive evidentiary base that approaches that of cardiac resynchronization therapy or pharmacological treatments for heart failure. This is particularly true, given its invasive nature and its considerable expense. (Excerpt from text, p. 400; no abstract available.)


Posted April 15th 2019

Quality control project of NGS HLA genotyping for the 17th International HLA and Immunogenetics Workshop.

Charles L. Cowey M.D.

Charles L. Cowey M.D.

Osoegawa, K., T. A. Vayntrub, S. Wenda, D. De Santis, K. Barsakis, M. Ivanova, S. Hsu, J. Barone, R. Holdsworth, M. Diviney, M. Askar . . . and M. A. Fernandez-Vina (2019). “Quality control project of NGS HLA genotyping for the 17th International HLA and Immunogenetics Workshop.” Hum Immunol 80(4): 228-236.

Full text of this article.

The 17th International HLA and Immunogenetics Workshop (IHIW) organizers conducted a Pilot Study (PS) in which 13 laboratories (15 groups) participated to assess the performance of the various sequencing library preparation protocols, NGS platforms and software in use prior to the workshop. The organizers sent 50 cell lines to each of the 15 groups, scored the 15 independently generated sets of NGS HLA genotyping data, and generated “consensus” HLA genotypes for each of the 50 cell lines. Proficiency Testing (PT) was subsequently organized using four sets of 24 cell lines, selected from 48 of 50 PS cell lines, to validate the quality of NGS HLA typing data from the 34 participating IHIW laboratories. Completion of the PT program with a minimum score of 95% concordance at the HLA-A, HLA-B, HLA-C, HLA-DRB1 and HLA-DQB1 loci satisfied the requirements to submit NGS HLA typing data for the 17th IHIW projects. Together, these PS and PT efforts constituted the 17th IHIW Quality Control project. Overall PT concordance rates for HLA-A, HLA-B, HLA-C, HLA-DPA1, HLA-DPB1, HLA-DQA1, HLA-DQB1, HLA-DRB1, HLA-DRB3, HLA-DRB4 and HLA-DRB5 were 98.1%, 97.0% and 98.1%, 99.0%, 98.6%, 98.8%, 97.6%, 96.0%, 99.1%, 90.0% and 91.7%, respectively. Across all loci, the majority of the discordance was due to allele dropout. The high cost of NGS HLA genotyping per experiment likely prevented the retyping of initially failed HLA loci. Despite the high HLA genotype concordance rates of the software, there remains room for improvement in the assembly of more accurate consensus DNA sequences by NGS HLA genotyping software.E


Posted April 15th 2019

Outcomes After Listing for Liver Transplant in Patients With Acute-on-Chronic Liver Failure: The Multicenter North American Consortium for the Study of End-Stage Liver Disease Experience.

Joyce O'Shaughnessy M.D.

Joyce O’Shaughnessy M.D.

O’Leary, J. G., J. S. Bajaj, P. Tandon, S. W. Biggins, F. Wong, P. S. Kamath, G. Garcia-Tsao, B. Maliakkal, J. Lai, M. Fallon, H. E. Vargas, P. Thuluvath, R. Subramanian, L. R. Thacker and K. R. Reddy (2019). “Outcomes After Listing for Liver Transplant in Patients With Acute-on-Chronic Liver Failure: The Multicenter North American Consortium for the Study of End-Stage Liver Disease Experience.” Liver Transpl 25(4): 571-579.

Full text of this article.

Acute-on-chronic liver failure (ACLF) characterized with >/=2 extrahepatic organ failures in cirrhosis carries a high mortality. Outcomes of patients listed for liver transplantation (LT) after ACLF and after LT are largely unknown. The North American Consortium for the Study of End-Stage Liver Disease prospectively enrolled 2793 nonelectively hospitalized patients with cirrhosis; 768 were listed for LT. Within 3 months, 265 (35%) received a LT, 395 remained alive without LT, and 108 died/delisted. Compared with nonlisted patients, those listed were younger and more often had ACLF, acute kidney injury, and a higher admission Model for End-Stage Liver Disease (MELD) score. ACLF was most common in patients who died/delisted, followed by those alive with and without LT respectively, (30%, 22%, and 7%, respectively; P < 0.001). At LT, median MELD was 27.9% and 70% were inpatients; median time from hospitalization to LT was 26 days. Post-LT survival at 6 months was unchanged between those with and without ACLF (93% each at 6 months). There was no difference in 3- and 6-month mean post-LT creatinine in those with and without ACLF, despite those with ACLF having a higher mean pre-LT creatinine and a higher rate of perioperative dialysis (61%). In conclusion, patients with and without ACLF had similar survival after transplant with excellent renal recovery in both groups.