Mortality associated with antiarrhythmic medication for atrial fibrillation among patients with left ventricular hypertrophy

BACKGROUND

Atrial fibrillation (AF) guidelines recommend amiodarone as the preferred antiarrhythmic medication (AAM) in patients with left ventricular hypertrophy (LVH), due to potential pro-arrhythmic risk with other AAM. However, there are limited data to support this assertion.

METHODS

We retrospectively analyzed the records of 8204 patients who were prescribed AAM for AF and had transthoracic echocardiogram (TTE) at the multicenter, VA Midwest Health Care Network from 2000 to 2021. We excluded patients without LVH (septal or posterior wall dimension ≤1.4 cm). The primary outcome variable was all-cause mortality during antiarrhythmic therapy or within 6 months after stopping it. Propensity-stratified analyses were performed between amiodarone versus non-amiodarone (Vaughan-Williams Class I and III) AAM.

RESULTS

A total of 1277 patients with LVH (mean age 70.2 ± 9.5 years) were included in the analysis. Of these, 774 (60.6%) were prescribed amiodarone. Baseline characteristics of the two comparison groups were similar after propensity adjustment. After a median 1.40 years of follow-up, 203 (15.9%) patients died. Incidence rates per 100 patient-year follow-up was 9.02 (7.58-10.66) for amiodarone and 4.98 (3.91-62.56) for non-amiodarone. In propensity-stratified analysis, amiodarone use was associated with 1.58 times higher risk of mortality (95% CI 1.03-2.44; p = .038). Sub-group analysis in 336 (26.3%) patients with severe LVH showed no difference in mortality (HR 1.41, 95% CI 0.82-2.43, p = .21).

CONCLUSION

Among patients with AF and LVH, amiodarone was associated with a significantly higher mortality risk than other AAM.

Propafenone-associated Gross Hematuria: A Case Report and Review of the Literature

PURPOSE

Propafenone hydrochloride has been widely used for the treatment of supraventricular and ventricular arrhythmias. We present a case report of an 81-year-old patient with propafenone-associated gross hematuria.

METHODS

The Naranjo Adverse Drug Reaction Probability Scale was used to assess causality. We also performed a literature search to find publications that report propafenone-associated gross hematuria.

FINDINGS

The Naranjo scale generated a score of 6, suggesting a probable association between gross hematuria and propafenone therapy. Thirteen publications that reported an association between gross hematuria and propafenone administration were found.

IMPLICATIONS

A probable association exists between gross hematuria and propafenone.

Optimal antiarrhythmic drug therapy for electrical storm

Electrical storm, defined as 3 or more separate episodes of ventricular tachycardia or ventricular fibrillation within 24 hours, carries significant morbidity and mortality. These unstable ventricular arrhythmias have been described with a variety of conditions including ischemic heart disease, structural heart disease, and genetic conditions. While implantable cardioverter defibrillator implantation and ablation may be indicated and required, antiarrhythmic medication remains an important adjunctive therapy for these persons.

Combination drug therapy for patients with intractable ventricular tachycardia associated with right ventricular cardiomyopathy

BACKGROUND

Drug therapy for patients with right ventricular (RV) cardiomyopathy refractory to single-drug therapy and ablation has not been well defined.

METHODS

We reviewed our entire RV cardiomyopathy database (31 patients) and found four patients presenting with ventricular arrhythmias of RV origin refractory to single-drug therapy. These patients underwent complete evaluation for arrhythmogenic right ventricular cardiomyopathy (ARVC).

RESULTS

Following the revised 2010 task force criteria, of these four patients, three were diagnosed with ARVC, and one with cardiac sarcoidosis. These patients proved to be refractory to drug monotherapy and either failed or deemed to not be candidates for endocardial ablation. Their arrhythmias were ultimately controlled with combinations of sotalol, flecainide, and mexiletine.

CONCLUSIONS

In our experience, combination drug therapy is an effective treatment strategy for patients with ventricular tachycardia refractory to monotherapy and, in some cases, ablation. In addition, flecainide appears to be safe and effective for those with RV cardiomyopathy without significant left ventricular dysfunction.