Left ventricle strength weakens slowly in gout patients, with the first evidence often being left atrial volume enlargement. This appears to correlate with the development of tophi.
Pan KL, Lin JC, Lin CL, et al., The effects of gout on left atrial volume remodelling: a prospective echocardiographic study. Rheumatology (2014) doi: 10.1093/rheumatology/ket444 [e-pub ahead of print January 9, 2014].
The strength of the left ventricle becomes slowly impaired in patients with hyperuricemia and gout, which may appear first as left atrial volume (LAV) enlargement . This appears to be an independent predictor of tophi development, according to a new study from Taiwan.
The researchers assigned 173 patients to four groups according to their gout stage: stage 0 (35 age-matched controls), asymptomatic hyperuricemia (n = 30), gouty arthritis without tophi (n = 58), and gouty tophi (n = 50).
Elevated serum uric acid (UA), hyperuricemia, and left atrial volume index (LAVi) enlargement are both associated with impaired LV function.
Therefore they meaured UA levels for all patients and took Doppler echocardiography images to assess left ventricular (LV) volume and function during contractions and at rest, as well as LAV and function.
Serum UA levels were higher than control levels among patients with asymptomatic hyperuricemia, gouty arthritis without tophi, and gouty tophi -- as was the LV mass index, indicating LV enlargement.
The LAVi also increased progressively from the controls up to those with tophi, with each incremental increase corresponding to a 6.8% greater risk for developing tophi among the gouty arthritis patients.
LAV remodeling, or hypertrophy, puts increased pressure on the left ventricle to fill adequately and, in gout, greater LAV may not only be a predictor of adverse cardiac events but also of tophi, the researchers conclude.