HOUSTON (AP) — Nobel Peace Prize winner and former Polish President Lech Walesa was undergoing tests for heart failure and being evaluated as a potential heart transplant recipient, Houston's Methodist DeBakey Heart & Vascular Center said Tuesday.

A brief announcement from the heart center did not detail the extent of the 64-year-old Walesa's condition.

The former electrician at what was then known as the Lenin Shipyards in Gdansk rose to power as the leader of the Solidarity trade union that emerged from a 1980 strike at the shipyard.