Final answer:
Class IV antiarrhythmics, or calcium channel blockers, can cause cardiovascular effects like hypotension, bradycardia, reduced stroke volume, and in extreme cases, cardiac arrest. They can also lead to non-cardiovascular effects such as constipation and dizziness and exacerbate conditions like ALS due to calcium-mediated excitotoxicity.
Step-by-step explanation:
The potential toxicities or adverse effects associated with Class IV antiarrhythmics, commonly known as calcium channel blockers (CCBs), include both cardiovascular and non-cardiovascular outcomes. Among the cardiovascular effects are hypotension (low blood pressure), bradycardia (slow heart rate), and the potential for heart failure due to the negative inotropic effect, which is a reduction in the strength of the heart's contraction. This effect can lead to a decrease in stroke volume (SV). Additionally, high levels of calcium ions (hypercalcemia) can lead to a short QT interval and a widened T wave in an electrocardiogram (ECG), and in extreme cases, cardiac arrest. Non-cardiovascular effects may include constipation, dizziness, headache, and peripheral edema. Furthermore, calcium channel blockers can exacerbate certain conditions, such as amyotrophic lateral sclerosis (ALS) through a mechanism known as calcium-mediated excitotoxicity.