Incidence, predictors, and clinical course of atrial tachyarrhythmias in patients with pulmonary hypertension.

Background: The prevalence and predictors of atrial tachyarrhythmias (ATa) in patients with pulmonary hypertension (PH) is less well understood.
Methods: We performed a retrospective study including 311 patients with PH, confirmed by right heart catheterization in our center between 2007 and 2011. Baseline characteristics, clinical, echocardiographic, and hemodynamic data were collected and compared between patients with and without ATa.
Results: The mean age was 61 ± 13 years with 64 % females. The mean pulmonary artery pressure (mPAP) was 46 ± 20 mmHg, mean left ventricular ejection fraction (LVEF) was 55 ± 13 %, and mean pulmonary capillary wedge pressure (PCWP) was 19 ± 9 mmHg. Of the 311 patients with PH, 121 (39 %) patients had ATa. Patients with ATa were older (p<0.001) and were more likely to have systemic hypertension (p=0.03), diabetes (p=0.015), coronary artery disease (p<0.001), heart failure (p<0.001), mitral regurgitation (p=0.001), impaired LVEF (p=0.02), and left atrial enlargement (p<0.001). There was no difference in the prevalence of ATa in mild, moderate, or severe PH. The mean PCWP was higher in patients with ATa (17.9 ± 9 vs 20.3 ± 8; p=0.022). In multivariate analysis using Cox-proportional hazard model, the independent predictors of mortality were age (HR 1.05; p=0.003), coronary artery disease (HR 2.34; p=0.047), LVEF (HR 0.793; p=0.023), and mPAP (HR 1.023; p=0.003).
Conclusion: ATa are common in patients with PH. Left heart disease, left atrial enlargement, and elevated PCWP but not right atrial enlargement or mPAP predict the occurrence of ATa in patients with PH.