Statin Therapy Significantly Reduces Risk of Ventricular Tachyarrhythmias in Patients With an Implantable Cardioverter Defibrillator

Mechanisms Underlying Antiarrhythmic Properties of Cardioprotective Agents Impacting Inflammation and Oxidative Stress

The prevention of cardiac life-threatening ventricular fibrillation and stroke-provoking atrial fibrillation remains a serious global clinical issue, with ongoing need for novel approaches. Numerous experimental and clinical studies suggest that oxidative stress and inflammation are deleterious to cardiovascular health, and can increase heart susceptibility to arrhythmias. It is quite interesting, however, that various cardio-protective compounds with antiarrhythmic properties are potent anti-oxidative and anti-inflammatory agents. These most likely target the pro-arrhythmia primary mechanisms. This review and literature-based analysis presents a realistic view of antiarrhythmic efficacy and the molecular mechanisms of current pharmaceuticals in clinical use. These include the sodium-glucose cotransporter-2 inhibitors used in diabetes treatment, statins in dyslipidemia and naturally protective omega-3 fatty acids. This approach supports the hypothesis that prevention or attenuation of oxidative and inflammatory stress can abolish pro-arrhythmic factors and the development of an arrhythmia substrate. This could prove a powerful tool of reducing cardiac arrhythmia burden.

Implantable cardioverter defibrillator shocks from ventricular tachyarrhythmias in patients with ischemic heart disease: Preventative measures, shortcomings, cost-effectiveness, and global practice perspectives

Implantable cardioverter defibrillators (ICDs) have proven to be life-saving devices in patients with ischemic cardiomyopathy (ICM) who are prone to develop ventricular tachycardia (VT) and fibrillation (VF). Antiarrhythmic drugs (AADs) are commonly prescribed in many such patients with ICDs to treat and prevent different forms of arrhythmias in clinical practice. When these patients experience recurrent monomorphic VT despite chronic AADs therapy, or when AAD therapy is contraindicated or not tolerated, and VT storm is refractory to AAD therapy, catheter ablation constitute guideline-based class I indication of treatment. However, what should be the most appropriate strategy to prevent first ICD shock or subsequent multiple shocks from VT/VF in patients with ICM who undergo ICD implantation without prior incidence of cardiac arrest, remains debatable. The purpose of this review is to discuss preventative aspects of ICD shocks for VT and the shortcomings of these measures along with the cost-effectiveness and global perspectives based on the current knowledge of the topic.

Lower In-Hospital Ventricular Tachyarrhythmia in Patients With Acute Myocardial Infarction Receiving Prior Statin Therapy

We evaluated whether prior statin therapy reduces in-hospital ventricular tachycardia/ventricular fibrillation (VT/VF) in percutaneous coronary intervention (PCI) patients with acute myocardial infarction (MI). Among the 1177 patients from the Acute Myocardial Infarction Registry-National Institutes of Health (KAMIR-NIH), 823 (70%) patients received prior statin therapy. Prior statin therapy was associated with a reduced risk of VT/VF events in both adjusted propensity score analysis (odds ratio [OR] 0.414, 95% confidence interval [CI], 0.198-0.865, P = .019) and adjusted inverse probability of treatment weight analysis (OR 0.463, 95% CI, 0.216-0.994, P = .048). The risk of in-hospital death did not differ significantly between those with or without prior statin therapy (hazard ratio [HR] 0.416, 95% CI, 0.112-1.548, P = .191). Major adverse cardiac events occurred in 116 (8.9%) patients during follow-up. Prior statin therapy was associated with a lower risk of major adverse cardiac events during the follow-up period (HR 0.486, 95% CI, 0.243-0.974, P = .042); however, this was mainly driven by reduced noncardiac death. Prior statin therapy might reduce the incidence of serious cardiac tachyarrhythmia, such as VT/VF, in patients with MI undergoing PCI. However, the reduction in VT/VF due to prior statin therapy did not improve short- and long-term clinical outcomes.

Defibrillation for Ventricular Fibrillation: A Shocking Update

Cardiac arrest is defined as the termination of cardiac activity associated with loss of consciousness, of spontaneous breathing, and of circulation. Sudden cardiac arrest and sudden cardiac death (SCD) are terms often used interchangeably. Most patients with out-of-hospital cardiac arrest have shown coronary artery disease or symptoms during the hour before the event. Cardiac arrest is potentially reversible by cardiopulmonary resuscitation, defibrillation, cardioversion, cardiac pacing, or treatments targeted at the underlying disease (e.g., acute coronary occlusion). We restrict SCD hereafter to cardiac arrest due to ventricular fibrillation, including rhythms shockable by an automatic external defibrillator (AED), implantable cardioverter-defibrillator (ICD), or wearable cardioverter-defibrillator (WCD). We summarize the state of the art related to defibrillation in treating SCD, including a brief history of the evolution of defibrillation, technical characteristics of modern AEDs, strategies to improve AED access and increase survival, ancillary treatments, and use of ICDs or WCDs.

Impact of statin therapy on all-cause mortality and ICD interventions in heart failure patients - a systematic review

OBJECTIVES

Implantable cardioverter defibrillators (ICDs) have a unique role for the primary and secondary prevention of sudden cardiac death (SCD). The aim of our systematic review is to present the existing data about the impact of statins on all-cause mortality and ICD interventions in heart failure (HF) patients who had an ICD implanted either for primary or for secondary prevention of SCD.

METHODS AND RESULTS

We searched PubMed database and the reference list of the relevant studies for retrieving studies evaluating the effect of statins on all-cause mortality and ICD interventions in HF patients. We finally included 17 relevant studies in our systematic review. Of them, nine studies included data about the impact of statins on all-cause mortality, eight studies about the impact of statins on appropriate ICD interventions and three studies about the impact of statins on inappropriate ICD interventions in HF patients. These data showed that statins seem to have a beneficial role in the reduction of all-cause mortality and ICD interventions in HF patients.

CONCLUSIONS

Statins seem to have a beneficial role in the reduction of all-cause mortality and ICD interventions in HF patients. However, further research about pleiotropic effects of statins is needed as well randomized control trials to elucidate the exact role of statin therapy in ICD outcomes.