Specialty DigestSpecialty KnowledgeClear, sourced answers to the terms and ideas you meet in the news, at work and in study.Search Specialty KnowledgeSearchABCDEFGHIJKLMNOPQRSTUVWXYZEntries starting with HHypertensionHypertension is blood pressure that stays too high over time, straining the heart, blood vessels, brain and kidneys.