Subclinical left atrium remodelling in patients with frequent premature ventricular contractions

Background: Premature ventricular contractions (PVCs) may cause subtle changes in left atrium (LA) structure and function which may not be readily detected by conventional parameters. Aim: To explore the relationship between PVCs and LA shape and size remodelling in patients without known structural heart disease. Methods: PVC frequency per 24 h was divided into tertiles. Echocardiographic measurements included left ventricular ejection fraction (LVEF) and volume, LA volume (LAV), mid-LA transverse diameter (LAt), and basal LA maximal transverse diameter (LAb). Trapezoidal LA shape was defined by LAt less than LAb. The association between PVCs and LA shape was explored by multivariable adjusted logistic regression. Results: The 121 patients had a mean age of 43.1 years (63% male) and mean LVEF of 56%. Mean LAV was 57.7 mL in the lowest PVC tertile, 70.9 mL in the middle, and 87.1 mL in the highest PVC tertile (p < 0.001). Trapezoidal LA shape was documented in 32 patients. Five per cent of patients in the lowest and 65% in the highest PVC tertile had trapezoidal LA shape (p < 0.001). PVC frequency correlated with LAV (r = 0.87, p < 0.001) and LAb (r = 0.56, p < 0.001). Each 10% increase in PVCs was significantly associated with trapezoidal LA shape (OR = 1.32, 95% CI 1.17-1.48), after adjustment for age, sex, mean blood pressure, LVEF, and LV end-diastolic diameter. Conclusions: Frequent PVCs are associated with larger LAV and trapezoidal LA shape in otherwise healthy patients, suggesting LA remodelling in response to increased LV filling pressure.