cardiac  function


Cardiovascular system


Symptoms of the following problems must be sought in all patients:

  • ischaemic heart disease;
  • heart failure;
  • hypertension;
  • conduction defects, arrhythmias;
  • peripheral vascular disease.

Patients with a proven history of myocardial infarction (MI) are at a greater risk of perioperative reinfarction, the incidence of which is related to the time interval between infarct and surgery.

This time is variable. In a patient with an uncomplicated MI and a normal exercise test elective surgery may only need to be delayed by 6–8 weeks.

The American Heart Association has produced guidance for perioperative cardiovascular evaluation.


Heart failure is one of the most significant indicators of perioperative complications, associated with increased risk of perioperative cardiac morbidity and mortality.  Its severity is best described using a recognized scale, for example the New York Heart Association classification (image up).


Untreated or poorly controlled hypertension may lead to exaggerated cardiovascular responses during anaesthesia. Both hypertension and hypotension can be precipitated, which increase the risk of myocardial and cerebral ischaemia.


The severity of hypertension will determine the action required:

  • Mild (SBP 140–159mmHg, DBP 90–99mmHg) No evidence that delaying surgery for treatment affects outcome.
  • Moderate (SBP 160–179mmHg, DBP 100–109 mmHg) Consider review of treatment. If unchanged, requires close monitoring to avoid swings during anaesthesia and surgery.
  • Severe (SBP > 180mmHg, DBP > 109mmHg) At this level, elective surgery should be postponed due to the significant risk of myocardial ischaemia, arrhythmias and intracerebral haemorrhage. In an emergency, will require acute control with invasive monitoring.