Which statement is true regarding myocardial functioning in the normal heart, based upon the Frank Starling law?
An increase in afterload results in decreased systolic pressure, which creates a decreased cardiac output.
A decrease in afterload causes the cardiac muscles to hypertrophy, resulting in increased diastolic volume.
An increase in preload results in greater shortening of myocardial fibers, thereby increasing contractility.
A decrease in preload results in increasing diastolic muscle fiber length, which impedes contractility.
The Correct Answer is C
A) An increase in afterload results in decreased systolic pressure, which creates a decreased cardiac output:
This statement is not consistent with the Frank-Starling law. Afterload refers to the resistance against which the heart must pump blood during systole. An increase in afterload typically results in increased systolic pressure, not decreased, as the heart works harder to overcome the increased resistance. However, increased afterload can lead to decreased cardiac output due to the increased work of the heart.
B) A decrease in afterload causes the cardiac muscles to hypertrophy, resulting in increased diastolic volume:
This statement is not consistent with the Frank-Starling law. Afterload refers to the pressure or resistance against which the heart must pump blood during systole. A decrease in afterload typically reduces the workload on the heart, which may lead to reverse remodeling and a reduction in cardiac hypertrophy. Increased diastolic volume may occur due to reduced afterload, but it's not the direct result of hypertrophy.
C) An increase in preload results in greater shortening of myocardial fibers, thereby increasing contractility:
Correct. According to the Frank-Starling law, an increase in preload (end-diastolic volume or stretch of myocardial fibers) leads to greater overlap of actin and myosin filaments within myocardial fibers during systole. This increased overlap results in stronger myocardial contraction (increased contractility), leading to an increased stroke volume and cardiac output.
D) A decrease in preload results in increasing diastolic muscle fiber length, which impedes contractility:
This statement is not consistent with the Frank-Starling law. Preload refers to the degree of stretch of the myocardial fibers at the end of diastole. A decrease in preload would lead to decreased stretch of the myocardial fibers, not increasing diastolic muscle fiber length. Decreased preload typically results in decreased contractility rather than impediment to contractility due to reduced myocardial stretch.
Nursing Test Bank
Naxlex Comprehensive Predictor Exams
Related Questions
Correct Answer is C
Explanation
A) Small, skin-colored, pedunculated papules in areas of skin folds and on other areas as skin tags:
This description is more characteristic of acrochordons (skin tags), which are benign skin growths often found in skin folds. Skin tags are typically not associated with acne vulgaris.
B) Hyperpigmented areas that vary in form and color and are slightly elevated from the skin:
This description may be indicative of post-inflammatory hyperpigmentation, which can occur after resolution of acne lesions. However, it does not represent the primary pathological findings observed in acne vulgaris.
C) Hyperactive sebaceous areas forming comedones, papules, pustules on the face, neck, and upper back:
Correct. Acne vulgaris is characterized by hyperactive sebaceous glands, leading to the formation of comedones (blackheads and whiteheads), papules, and pustules. These lesions commonly occur on the face, neck, and upper back due to the high density of sebaceous glands in these areas.
D) Sharply demarcated silvery scaling plaques with underlying redness on the elbows and knees:
This description is more indicative of psoriasis, a chronic autoimmune skin condition characterized by silvery scaling plaques and inflammation. Psoriasis typically affects extensor surfaces such as the elbows and knees, rather than the areas commonly affected by acne vulgaris.
Correct Answer is B
Explanation
A) Nerve degeneration due to chronic gastric reflux:
Nerve degeneration due to chronic gastric reflux may lead to conditions such as gastroesophageal reflux disease (GERD) or esophagitis, but it is not directly related to the clinical presentation of intestinal obstruction. Symptoms of GERD or esophagitis typically include heartburn, regurgitation, and dysphagia rather than severe, colicky abdominal pain, nausea, vomiting, and abdominal distention.
B) Volvulus that occurred during an appendectomy:
Correct. Volvulus refers to the twisting of a segment of the intestine around its mesentery, leading to obstruction of the bowel lumen and compromising blood flow to the affected area. In this scenario, the client's clinical presentation of severe, colicky abdominal pain, nausea, vomiting, and abdominal distention is consistent with symptoms of intestinal obstruction, which can occur secondary to volvulus. Volvulus may result from various factors, including prior abdominal surgeries, such as an appendectomy, leading to abnormal positioning or adhesions within the abdomen.
C) Esophagitis due to reflux of gastric contents:
Esophagitis due to reflux of gastric contents can cause symptoms such as heartburn, chest pain, and difficulty swallowing, but it is not typically associated with severe, colicky abdominal pain, nausea, vomiting, and abdominal distention characteristic of intestinal obstruction.
D) A history of having Helicobacter pylori infection:
Helicobacter pylori infection is associated with conditions such as peptic ulcer disease and gastritis, but it is not directly related to the clinical presentation of intestinal obstruction. Symptoms of H. pylori infection may include abdominal pain, nausea, and vomiting, but they are not typically colicky and severe as those seen in intestinal obstruction.
Whether you are a student looking to ace your exams or a practicing nurse seeking to enhance your expertise , our nursing education contents will empower you with the confidence and competence to make a difference in the lives of patients and become a respected leader in the healthcare field.
Visit Naxlex, invest in your future and unlock endless possibilities with our unparalleled nursing education contents today
Report Wrong Answer on the Current Question
Do you disagree with the answer? If yes, what is your expected answer? Explain.
Kindly be descriptive with the issue you are facing.
