Diseases Commons^™

Effect Of Flecainide And Ibutilide Alone And In Combination To Terminate And Prevent Recurrence Of Atrial Fibrillation, Alexander Burashnikov, José M. Di Diego, Bence Patocskai, Debra S. Echt, Luiz Belardinelli, Charles Antzelevitch

Division of Cardiology Faculty Papers

BACKGROUND: There is a need for improved approaches to rhythm control therapy of atrial fibrillation (AF).

METHODS: The effectiveness of flecainide (1.5 µmol/L) and ibutilide (20 nmol/L), alone and in combination, to cardiovert and prevent AF recurrence was studied in canine-isolated coronary-perfused right atrioventricular preparations. We also examined the safety of the combination of flecainide (1.5 µmol/L) and ibutilide (50 nmol/L) using canine left ventricular wedge preparations.

RESULTS: Sustained AF (>1 hour) was inducible in 100%, 60%, 20%, and 0% of atria in the presence of acetylcholine alone, acetylcholine+ibutilide, acetylcholine+flecainide, and acetylcholine+ibutilide+flecainide, respectively. When used alone, flecainide and ibutilide …

Interplay Of Hypoxia-Inducible Factors And Oxygen Therapy In Cardiovascular Medicine, Yafen Liang, Wei Ruan, Yandong Jiang, Richard Smalling, Xiaoyi Yuan, Holger K Eltzschig

Journal Articles

Mammals have evolved to adapt to differences in oxygen availability. Although systemic oxygen homeostasis relies on respiratory and circulatory responses, cellular adaptation to hypoxia involves the transcription factor hypoxia-inducible factor (HIF). Given that many cardiovascular diseases involve some degree of systemic or local tissue hypoxia, oxygen therapy has been used liberally over many decades for the treatment of cardiovascular disorders. However, preclinical research has revealed the detrimental effects of excessive use of oxygen therapy, including the generation of toxic oxygen radicals or attenuation of endogenous protection by HIFs. In addition, investigators in clinical trials conducted in the past decade have …

Prolylcarboxypeptidase Alleviates Hypertensive Cardiac Remodeling By Regulating Myocardial Tissue Angiotensin Ii, Binh Y Nguyen, Fangchao Zhou, Pablo Binder, Wei Liu, Susanne S Hille, Xiaojing Luo, Min Zi, Hongyuan Zhang, Antony Adamson, Fozia Z Ahmed, Sam Butterworth, Elizabeth J Cartwright, Oliver J Müller, Kaomei Guan, Elizabeth M Fitzgerald, Xin Wang

Journal Articles

Background Prolonged activation of angiotensin II is the main mediator that contributes to the development of heart diseases, so converting angiotensin II into angiotensin 1-7 has emerged as a new strategy to attenuate detrimental effects of angiotensin II. Prolylcarboxypeptidase is a lysosomal pro-X carboxypeptidase that is able to cleave angiotensin II at a preferential acidic pH optimum. However, insufficient attention has been given to the cardioprotective functions of prolylcarboxylpeptidase. Methods and Results We established a CRISPR/CRISPR-associated protein 9-mediated global prolylcarboxylpeptidase-knockout and adeno-associated virus serotype 9-mediated cardiac prolylcarboxylpeptidase overexpression mouse models, which were challenged with the angiotensin II infusion (2 mg/kg …

Targeting Myocardial Equilibrative Nucleoside Transporter Ent1 Provides Cardioprotection By Enhancing Myeloid Adora2b Signaling, Wei Ruan, Jiwen Li, Seungwon Choi, Xinxin Ma, Yafen Liang, Ragini Nair, Xiaoyi Yuan, Tingting W Mills, Holger K Eltzschig

Journal Articles

Previous studies implicate extracellular adenosine signaling in attenuating myocardial ischemia and reperfusion injury (IRI). This extracellular adenosine signaling is terminated by its uptake into cells by equilibrative nucleoside transporters (ENTs). Thus, we hypothesized that targeting ENTs would function to increase cardiac adenosine signaling and concomitant cardioprotection against IRI. Mice were exposed to myocardial ischemia and reperfusion injury. Myocardial injury was attenuated in mice treated with the nonspecific ENT inhibitor dipyridamole. A comparison of mice with global Ent1 or Ent2 deletion showed cardioprotection only in Ent1-/- mice. Moreover, studies with tissue-specific Ent deletion revealed that mice with myocyte-specific Ent1 deletion (Ent1loxP/loxP …