Utility of Routine Exercise Testing to Detect Rate-Related QRS Widening in Patients Without Structural Heart Disease on Class Ic Antiarrhythmic Agents (Flecainide and Propafenone)

2024 HRS expert consensus statement on arrhythmias in the athlete: Evaluation, treatment, and return to play

Youth and adult participation in sports continues to increase, and athletes may be diagnosed with potentially arrhythmogenic cardiac conditions. This international multidisciplinary document is intended to guide electrophysiologists, sports cardiologists, and associated health care team members in the diagnosis, treatment, and management of arrhythmic conditions in the athlete with the goal of facilitating return to sport and avoiding the harm caused by restriction. Expert, disease-specific risk assessment in the context of athlete symptoms and diagnoses is emphasized throughout the document. After appropriate risk assessment, management of arrhythmias geared toward return to play when possible is addressed. Other topics include shared decision-making and emergency action planning. The goal of this document is to provide evidence-based recommendations impacting all areas in the care of athletes with arrhythmic conditions. Areas in need of further study are also discussed.

Atrial Fibrillation Management: A Comprehensive Review with a Focus on Pharmacotherapy, Rate, and Rhythm Control Strategies

Atrial fibrillation (AF) is an increasingly common arrhythmia encountered in clinical practice that leads to a substantial increase in utilization of healthcare services and a decrease in the quality of life of patients. The prevalence of AF will continue to increase as the population ages and develops cardiac comorbidities; thus, prompt and effective treatment is important to help mitigate systemic resource utilization. Treatment of AF involves two tenets: prevention of stroke and systemic embolism and symptom control with either a rate or a rhythm control strategy. Historically, due to the safe nature of medications like beta-blockers and non-dihydropyridine calcium channel blockers, used in rate control, it has been the initial strategy used for symptom control in AF. Newer data suggest that a rhythm control strategy with antiarrhythmic medications with or without catheter ablation may lead to a reduction in major adverse cardiovascular events, particularly in patients newly diagnosed with AF. Modulation of factors that promote AF or its complications is another important aspect of the overall holistic management of AF. This review provides a comprehensive focus on the management of patients with AF and an in-depth review of pharmacotherapy of AF in the rate and rhythm control strategies.

Anti-arrhythmic therapy in athletes

The spectrum of arrhythmias that may be encountered in athletes ranges from isolated ectopic beats to ventricular tachycardia, usually in the context of a structurally normal heart. Anti-arrhythmic therapy in these individuals may be particularly challenging because of the young age, the hypervagotonic state, the desire to maintain a high physical performance, the reluctance to take medications and the need to avoid molecules included in the list of prohibited drugs of the World Anti-Doping Agency. Furthermore, the possible serious adverse effects of anti-arrhythmic drugs should be balanced against the benign nature of arrhythmias in patients with no underlying heart disease. The review summarizes the most common arrhythmias of athletes and the possible therapeutic options, including anti-arrhythmic drugs and non-pharmacological interventions. Eligibility criteria according to current guidelines are also addressed.

Atrial Flutter With Exercise-Induced 1:1 Atrioventricular Conduction

Typical atrial flutter is a common atrial tachyarrhythmia. Symptoms are typically related to the rate of ventricular response. Although atrial flutter with 1:1 atrioventricular conduction is rare, it is important to recognize because it may precipitate rapid hemodynamic compromise. The authors present a case of exercise-induced 1:1 atrioventricular conduction in a patient with typical atrial flutter.

Initiation and outcomes with Class Ic antiarrhythmic drug therapy

BACKGROUND

Expert opinion recommends performing exercise testing with initiation of Class Ic antiarrhythmic medication.

OBJECTIVE

To evaluate the rate and reason for discontinuation of Ic agent within the first year of follow up, with particular attention to rate of proarrhythmia and the value of routine treadmill testing.

METHODS

This is a single center retrospective cohort study including consecutive patients with atrial arrhythmias who were initiated on a Class Ic agent from 2011 to 2016. Data was collated from chart review and pharmacy database.

RESULTS

The study population included 300 patients (55% male, mean age 61; mean ejection fraction, 56%) started on flecainide (n = 153; 51%) and propafenone (n = 147; 49%). Drug initiation was completed while hospitalized on telemetry and the staff electrophysiologists directed dosing. There was one proarrhythmic event during initiation (0.3%). The primary reason for not being discharged on Ic agent was due to detection of proarrhythmia (n = 15) or ischemia (n = 1) with treadmill testing (5.3%). Exercise testing was the single significant variable to affect the decision to discontinue Ic drug, p < 0.0001 (95% CI: 1.89-6.08%). During follow up, the primary reason for discontinuation of Ic agent was lack of efficacy, 32%.

CONCLUSIONS

With proper screening, initiation of Class Ic agent is associated with very low rate of proarrhythmia. Treadmill testing is of incremental value and should be completed in all patients after loading Class Ic antiarrhythmic.

Impact of QT interval prolongation following antiarrhythmic drug therapy on left ventricular function

AIM

We assessed whether antiarrhythmic drug-induced QT interval prolongation affects left ventricular function.

METHODS

Study population included 54 patients with symptomatic recent onset atrial fibrillation spontaneously cardioverted to sinus rhythm. Electrocardiographic and echocardiographic studies were done before initiating and after achieving drug's steady state.

RESULTS

Significantly prolonged corrected QT interval (QTc) was noticed following only sotalol and amiodarone. The corrected precontraction time increased after sotalol (p = 0.005) and amiodarone (p = 0.017), not propafenone (p = 0.139). Analysis results between ΔEF and ΔQTc, ΔEF and ΔQTc(p), ΔE/e' and ΔQTc, ΔE/e' and ΔQTc(p) for amiodarone group were (p = 0.66, p = 0.20, p = 0.66, p = 0.33), for sotalol (p = 0.36, p = 0.51, p = 0.44, p = 0.33) and for propafenone (p = 0.38, p = 0.12, p = 0.89, p = 0.61), respectively.

CONCLUSION

QT interval prolongation following antiarrhythmic therapy does not affect significantly left ventricular function.