Final answer:
Congestive heart failure presents with symptoms like dyspnea, edema, and fatigue. Its pathophysiology includes impaired heart pumping and maladaptive compensatory mechanisms. Factors affecting contractility, stroke volume, and cardiac output are crucial in understanding heart response to changes in blood flow and pressure.
Step-by-step explanation:
Clinical Picture of Congestive Heart Failure
The clinical picture of congestive heart failure (CHF) includes symptoms such as dyspnea (shortness of breath), chronic coughing or wheezing, edema (swelling) in the feet, ankles, legs, or abdomen, fatigue, impaired thinking, and increased heart rate. Patients with CHF may also experience weight gain due to fluid retention and decreased ability to exercise.
General Pathophysiology of Congestive Heart Failure
The pathophysiology of CHF generally entails a complex interplay between decreased cardiac output due to impaired pump function of the heart, and the compensatory mechanisms that the body employs in an attempt to maintain adequate circulation. Over time, these compensatory mechanisms, such as neurohormonal activation and ventricular remodeling, can further damage the heart and exacerbate heart failure.
Factors That Affect Heart Contractility
Positive factors that enhance heart contractility include increased sympathetic stimulation and certain medications. Negative factors include myocardial ischemia and damage from myocardial infarction. Contractility is closely related to stroke volume and cardiac output, where stroke volume refers to the amount of blood ejected by the heart with each beat, and cardiac output is the total volume of blood pumped by the heart per minute.
Cardiac Response to Variations in Blood Flow and Pressure
The heart responds to changes in blood flow and pressure through mechanisms such as the Frank-Starling law of the heart, which states that the stroke volume of the heart increases in response to an increase in the volume of blood filling the heart (the end diastolic volume) when all other factors remain constant.