This patient has the capacity to make a decision about the proposed procedure; therefore, the physician should proceed with coronary angiography. Informed consent includes a discussion of the information that a reasonable patient would want to know about his or her illness (proposed diagnostic and treatment plans, the risks and benefits of the proposed plans, and any alternatives), an assessment of patient understanding, and the acceptance or refusal of the treatment. The patient must have decision-making capacity and make each decision of his or her own free will for consent to be considered valid. A patient (for example, one with mild dementia) may have the capacity to make some decisions but not other more complex ones. The graver the consequences of the decision, the greater the capacity required. Decision-making capacity exists when a patient demonstrates an ability to understand relevant information, appreciate the situation and its possible consequences, manipulate information rationally, and make a reasoned choice. Despite this patient's mild dementia, he fulfills these standards and therefore has the capacity to make a decision regarding the procedure.

There is no need to wait for the patient's wife to consent to the procedure. Indeed, waiting for his wife to arrive and delaying treatment increases the patient's risk for harm.

A Mini-Mental State Examination is unnecessary. It will likely confirm the diagnosis of mild dementia but will not help in assessing the patient's decision-making capacity. A diagnosis of dementia or a mental illness does not necessarily mean that a patient is incapable of making health care decisions. The clinician must assess whether or not the patient's decision appears consistent with his or her values and goals of care. If it does, it can probably be accepted as valid.

It is unnecessary to obtain a second opinion to assess this patient's decision-making capacity. The core components of decision-making capacity are understanding the situation at hand, understanding the risks and benefits of the decision being made, and the ability to communicate a decision. The patient has demonstrated these core elements.