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Odd couple: premature ventricular contractions and heart failure

The interplay between frequent premature ventricular complexes (PVCs) and the development of left ventricular systolic dysfunction (LVSD) and heart failure (HF) is not a simple one. The first described relationship between frequent PVCs and LV dysfunction was in 1998, but importantly this was a description of patients with frequent PVCs and established LVSD, that improved with suppression of PVCs using amiodarone. On the surface, the concept was simple: a high burden of PVCs leads to (or at least contributes to) LVSD and HF. However, the more we learn about PVCs and HF, the more complex the relationship becomes, further highlighted in the current study from Limpitikul and colleagues. The study is an analysis of patients with available raw Holter data nested within the prospective Cardiovascular Health Study (CHS). From the original randomly selected 5201 adults ≥65 years recruited in 1989–1990, 1429 were randomly selected to undergo 24 Holter monitor. After exclusions, 871 participants were available, of whom 316 had ≥10 PVCs on monitoring and form the basis of analysis. A further subgroup of 209 patients underwent both a baseline and 5year echocardiographic evaluation. The association between PVC characteristics and cardiovascular outcomes was examined over a median followup of 11 years.