Sinus Rhythm Restoration and Survival in PAH With Atrial Flutter/Fibrillation

Restoration of sinus rhythm is associated with greater functional improvement and survival in patients with pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH) and new-onset atrial flutter (AFL) and atrial fibrillation (AF) compared with rate control. These findings were published in the International Journal of Cardiology.

Researchers used the ASPIRE (Assessing the Spectrum of Pulmonary Hypertension Identified at a Referral Centre) registry to identify patients with PAH and CTEPH who had new-onset AFL or AF diagnosed at the Northern General Hospital, Sheffield, UK, between November 2004 and September 2019.

The participants were assigned to 1 of 3 management strategies: rate control (strategy 1), rhythm control with medications only (strategy 2), or rhythm control with direct current cardioversion (DCCV) with or without medications (strategy 3). Strategy 1 involved treatment with digoxin monotherapy, a nondihydropyridine calcium channel blocker, or a combination of digoxin and a cardioselective β blocker. In strategy 2, participants received amiodarone as monotherapy or combined with a rate control agent. Strategy 3 participants had DCCV with or without rate or rhythm control medications.

The strategy 1 and 2 groups were enrolled from 2009 to 2014, and the strategy 3 group was enrolled from 2014 to 2019. The investigators compared the rates of sinus rhythm restoration among the 3 groups.

A total of 71% patients had AFL and 29% had AF. Of the study cohort, 22% patients (median age at diagnosis, 69 years) received rate control, 26% patients (median age at diagnosis, 61 years) had medical rhythm control, and 52% patients (median age at diagnosis, 66 years) had DCCV. Sinus rhythm restoration was achieved by 33% of patients who received rate control, 59% of patients who had medical rhythm control, and 95% of patients who had DCCV (P <.001).

Restoration of sinus rhythm was associated with greater improvement in functional class and incremental shuttle walk distance (P <.05 for both), and it independently predicted superior survival (3-year survival, 62% vs 23% in participants remaining with AFL/AF; P <.0001).

Functional class III/IV independently predicted increased mortality (hazard ratio, 2.86; P =.007). Right atrial area independently predicted the recurrence of AFL/AF (odds ratio, 1.08; P =.01), and DCCV was generally well tolerated without any immediate major complications.

Study limitations include the retrospective design and heterogeneity of arrhythmia types among the groups. In addition, it is possible that some patients with AFL/AF were missed, and robust estimates of AFL/AF incidence are not possible. The investigators were unable to perform risk stratification, and a limited number of parameters could be assessed in survival analyses owing to the study size.

“…our study suggests that a heart rhythm control strategy is superior to a rate control strategy in patients with PAH/CTEPH, with sinus rhythm restoration being associated with superior survival and functional improvement,” wrote the study authors. “Furthermore, DCCV is generally safe and more effective at restoring sinus rhythm than pharmacological therapy in this patient group.”