Final answer:
To control tachycardia without medication, Karyn could try meditation and stress reduction techniques, which can lower heart rate by minimizing stress-related autonomic system responses.
Step-by-step explanation:
In managing symptoms of tachycardia associated with congestive heart failure, Karyn might benefit from meditation and stress reduction techniques to help control her rapid heart rate without additional medication. Meditation has been shown to ease anxiety and effectively lower heart rate by reducing the impact of the limbic system, which contributes to higher heart rates during periods of stress. In contrast, increasing caffeine intake could exacerbate tachycardia, as caffeine is a stimulant. Similarly, high-intensity interval training (HIIT) may not be suitable as it is likely to increase heart rate further. Consuming more saturated fats is also not advisable, as it could worsen heart health. Instead, maintaining electrolyte balance, particularly potassium levels, is critical to normal cardiac function and tachycardia management.