NURS 202 Chapter Notes - Chapter 20: Paroxysmal Nocturnal Dyspnoea, Fourth Heart Sound, Pulmonary Valve
Document Summary
The cardiovascular system: heart (muscular pump) + blood vessels (provide pulmonary and systemic circulation through two continuous loops) Left side of heart: blood return thru pulmonic vein l atrium mitral valve l ventricles aortic valve. Aorta out to extremities: heart sounds, the first heart sound (or s1) from closure of av valves. M1 slightly b4 t1 but heard as one sound: the second heart sound (or s2) from closure of the semilunar valves. For all heart sounds, describe their pitch, intensity, duration, and timing. Developmental changes: before birth, the foramen ovale allows oxygenated blood from the placenta to be shunted to the left side of the heart and out to the general circulation. In older adults, the systolic pressure , and the left ventricular wall thickness increases somewhat. The heart has a decreased ability to augment cardiac output with exercise, supraventricular and ventricular arrhythmias are more likely, and some electrocardiographic changes occur.
