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What is According to NYHA grading, Patients with marked limitation to physical activity belongs to and explain in detail?
New York Hea Association Functional Classification of Cardiac diseaseGrade I: Patients have no limitation of physical activityGrade II: Patients have slight limitation of physical activityGrade III: Patients have marked limitation of physical activityGrade IV: Patients have an inability to carry on the physical activity without symptomsReference: Practical Guide to High-Risk Pregnancy and Delivery; Chapter 20; Cardiac Disease and Pregnancy