The heart's natural pacemaker can fail — here's what happens when it does

Both treat electrical problems, but their roles differ significantly — one regulates rhythm, the other stops dangerous ones.
READ NEXT
More on the wire
FROM THE PUBLISHER
Taylor Swift drew attention during the Kansas City Chiefs’ game against the Indianapolis Colts when cameras caught her celebrating Travis Kelce’s first touchdown of the season.
FROM THE PUBLISHER
Atlanta Falcons receiver Drake London addressed a heated sideline confrontation during the Falcons’ 34-3 loss to the Carolina Panthers.
FROM THE PUBLISHER
Watson's second-half performance in Tampa Bay silenced a week's worth of national criticism and quarterback controversy.