Upper UTIs are infections of the kidneys. These are potentially life threatening, if bacteria move from the infected kidney into the blood. This condition is called sepsis. Sepsis can cause dangerously low blood pressures, shock, and death.
So whe you hold your breath, you stop getting oxygen in your lungs that go to your heart. The oxygen level in the blood drops, so your muscles need more oxygen, so the heart pumps faster. This is like running, your muscles need more oxygen so heart pumps faster
Second-degree heart block may result in the heart skipping a beat or beats. This type of heart block also can make you feel dizzy or faint. Third-degree heart block limits the heart's ability to pump blood to the rest of the body. This type of heart block may cause fatigue (tiredness), dizziness, and fainting. Third-degree heart block requires prompt treatment because it can be fatal. A medical device called a pacemaker is used to treat third-degree heart block and some cases of second-degree heart block.