Your father's condition of pericardial effusion, which is characterized by fluid accumulation around the heart, indeed raises significant concerns. In Ayurveda, this condition can be viewed through the lens of dosha imbalances, particularly relating to Kapha, since excess fluid is associated with Kapha. However, if inflammation is present, Pitta may also play a role. It's critical to address both the immediate concerns regarding fluid retention and the underlying causes contributing to his cardiovascular issues. To support your father, start with dietary modifications that focus on reducing Kapha and balancing Pitta. Incorporate lighter, well-cooked foods that support digestion, such as whole grains like brown rice or quinoa, and plenty of vegetables, particularly bitter greens like kale and spinach. Use spices like turmeric and ginger to enhance digestion and reduce inflammation. Encourage him to limit salty and processed foods, as they may worsen fluid retention. Herbs you've mentioned are indeed beneficial. Arjuna (Terminalia arjuna) can help strengthen the heart muscle and improve cardiovascular function. Punarnava (Boerhavia diffusa) is excellent for reducing fluid retention and can support kidney function, aiding in the elimination of excess fluids. Garlic (Allium sativum) is well-known for its cardiovascular benefits, including cholesterol management and promoting circulation. For integrating these, a tea made with these herbs or a supplemental extract can be utilized, but dosage should be guided by an Ayurvedic practitioner. In terms of heart tonics, consider a formulation that combines Arjuna and Punarnava, available in health stores or from Ayurvedic practitioners. Daily meditation and gentle yoga can further assist in improving circulation and reducing stress, which can indirectly benefit heart health. Additionally, warm oil massages (Abhyanga) using sesame or coconut oil can help pacify excess Kapha while improving circulation. For detoxification, a supervised Panchakarma, an Ayurvedic cleansing process, can be tremendously beneficial, but it should be carefully planned with a knowledgeable Ayurvedic practitioner. Encourage consistent hydration with warm water to support kidney function, and consider herbal teas such as ginger or fennel that promote digestion and fluid balance. Remember, while implementing these natural strategies, it's crucial to keep in regular contact with your father's healthcare provider to monitor his condition and adjust treatments as necessary. Integrating these Ayurvedic approaches can support his heart health and overall well-being effectively, but they should complement, not replace, conventional medical treatments for pericardial effusion.