The nurse is caring for a 24 year old post-partum client with a diagnosis of cardiomyopathy. The nurse understands that which of the following types of cardiomyopathy can be associated with childbirth?

A. Hypermagnesemia: Hypermagnesemia (high magnesium levels) can cause bradycardia, hypotension, and prolonged PR and QRS intervals. While it can affect cardiac rhythm, it's less commonly associated with PVCs. The client's magnesium level of 2.5 mg/dL is within the normal range (1.5-2.5 mg/dL).

B. Hypocalcemia: While the calcium level of 8.0 mg/dL is slightly low (normal: ~8.5–10.5 mg/dL), mild hypocalcemia is less commonly associated with PVCs compared to hypokalemia. It can affect cardiac contractility but is not the most likely cause of these arrhythmias.

C. Hypokalemia: The potassium level is 2.8 mEq/L, which is significantly below normal (normal: 3.5–5.0 mEq/L). Potassium is a crucial electrolyte for maintaining normal cardiac electrical activity. Hypokalemia increases myocardial excitability and can lead to various cardiac dysrhythmias and a known cause of ventricular irritability, including multifocal PVCs, and increases the risk of life-threatening arrhythmias in clients with cardiac or metabolic conditions.

D. Hyperglycemia: The glucose level of 200 mg/dL is elevated but not severely high. While it reflects poor glycemic control, it is not directly linked to the occurrence of PVCs. Electrolyte imbalances, particularly low potassium, are more arrhythmogenic.

A. "All patients with this disorder have a genetic defect which causes it.": Restrictive cardiomyopathy is not primarily a genetic disorder. While there may be rare familial forms, most cases are acquired, often secondary to systemic diseases, making this statement inaccurate and misleading.

B. "There are many theories about its development but amyloidosis in your history is a probable cause.": This is the most accurate response. Restrictive cardiomyopathy is commonly associated with infiltrative diseases such as amyloidosis, hemochromatosis, and sarcoidosis, which impair ventricular filling due to stiff, non-compliant myocardium.

C. "You probably had a silent heart attack which caused this disorder.": Silent myocardial infarctions can contribute to ischemic cardiomyopathy, typically leading to dilated, not restrictive, changes in the myocardium. They are not a primary cause of restrictive cardiomyopathy.

D. "Your long-standing hypertension caused this disorder.": Chronic hypertension more commonly leads to left ventricular hypertrophy and may contribute to diastolic heart failure, but it is not a typical cause of restrictive cardiomyopathy.