Bradycardia can be caused by: 1  Changes in the heart that are the result of aging.  Diseases that damage the heart's electrical system. These include coronary artery disease, heart attack, and infections such as endocarditis and myocarditis.
Portland Weather In May. The highest recorded temperature in May for Portland for the past 70 years was 100 degrees Fahrenheit, most recently measured on May 28, 1983, and the normal high is 67.
Summer temperatures in Eastern Oregon are the hottest in the state, usually into the upper 90's and low 100's. Winter temperatures are the coldest, with minus temps not uncommon. Rainfall is limited, and it is very dry here, although summer thunderstorms can occur.