Regardless of the exercise format, cardiac patients should be aware of four warning signs or symptoms that may indicate a worsening or progression of their heart disease: new onset or recurring anginal pain (chest pain or pressure, an ache in the jaw or neck, discomfort down the left or right arms, pain across the shoulders and back); unaccustomed or unusual shortness of breath; dizziness or lightheadedness; and, heart rhythm abnormalities. In such instances, exercise should be discontinued and medical attention sought.