Perioperative Cardiac Events

Perioperative cardiac events are the acute cardiovascular complications that arise around the time of non-cardiac surgery — including myocardial injury and infarction, arrhythmias, heart failure with low cardiac output, and cardiac arrest. They are among the most frequent serious complications of major surgery and a leading cause of postoperative death, which is why their recognition, surveillance, and risk stratification form a core concern of perioperative medicine.

Definition

Perioperative cardiac events are adverse cardiovascular outcomes occurring during or shortly after surgery, encompassing myocardial injury and infarction, significant arrhythmias, acute heart failure and low cardiac output states, and cardiac arrest; in non-cardiac surgery they are frequently detected through postoperative troponin elevation even when symptoms are absent.

Scope

This entry covers the spectrum of perioperative cardiovascular complications, the concept of myocardial injury after non-cardiac surgery and how troponin surveillance detects it, the mechanisms linking surgical stress to cardiac events, and how cardiac risk is assessed before operation. It treats these events as clinical entities and a reference topic, without providing medication regimens or individualised management instructions.

Core questions

• What is myocardial injury after non-cardiac surgery (MINS) and how is it detected?
• How does the physiological stress of surgery precipitate cardiac events?
• How is preoperative cardiac risk estimated?
• Why are many perioperative myocardial injuries clinically silent?

Key concepts

• Myocardial injury after non-cardiac surgery (MINS)
• Type 1 versus type 2 myocardial infarction
• High-sensitivity troponin surveillance
• Supply-demand mismatch and surgical stress response
• Perioperative arrhythmias and low cardiac output
• Preoperative cardiac risk stratification
• Universal definition of myocardial infarction

Mechanisms

Surgery provokes a stress response — sympathetic activation, inflammation, a prothrombotic shift, fluid and haemodynamic changes, and sometimes anaemia and hypoxaemia — that can tip vulnerable patients into myocardial ischaemia. Events arise both from acute plaque rupture with thrombosis (type 1 infarction) and, more commonly in this setting, from a mismatch between myocardial oxygen supply and demand without acute plaque disruption (type 2 injury). Because patients are sedated, on analgesics, and recovering, ischaemia is often painless, so much perioperative myocardial injury is silent and detected only by routine troponin measurement (Thygesen et al., 2018; VISION Study Investigators, 2017).

Clinical relevance

Perioperative cardiac events illustrate how a complication can be common yet frequently undetected without active surveillance, which has driven interest in postoperative troponin monitoring and structured preoperative risk assessment. They also show the limits of preventive pharmacology, since interventions intended to reduce cardiac events can carry offsetting harms. This entry describes how these events are defined, detected, and studied; it is not a source of perioperative drug or management recommendations.

Epidemiology

Cardiovascular complications are among the most frequent serious adverse events after major non-cardiac surgery and a leading contributor to postoperative mortality, with risk concentrated in older patients and those with established cardiovascular disease. Cohort surveillance shows that postoperative high-sensitivity troponin elevation, often without symptoms, is common and strongly associated with thirty-day mortality, reframing perioperative myocardial injury as a measurable and prognostically important entity (VISION Study Investigators, 2017; Halvorsen et al., 2022).

History

Perioperative cardiac risk moved from a clinical impression to a quantified field through successive risk indices and, later, through large international cohorts and trials. The POISE trial demonstrated that routine perioperative beta-blockade reduced myocardial infarction but increased stroke and death, a landmark caution against assuming benefit. The VISION programme then established the prognostic weight of asymptomatic troponin elevation, and the Universal Definition of Myocardial Infarction provided a shared framework distinguishing infarction subtypes (Devereaux et al., 2008; VISION Study Investigators, 2017; Thygesen et al., 2018).

Debates

Should patients undergo routine perioperative troponin surveillance?

Routine postoperative troponin testing detects prognostically important silent injury, but whether systematic screening improves outcomes — given uncertain treatment options for many such events — remains contested.

What is the role of perioperative beta-blockade?

After the POISE trial showed reduced infarction at the cost of increased stroke and mortality, routine initiation of beta-blockers solely for cardiac protection fell out of favour, and the balance of benefit and harm continues to be debated.

Seminal works

• devereaux-2008-poise
• vision-2017
• thygesen-2018

Frequently asked questions

What is myocardial injury after non-cardiac surgery (MINS)?

MINS refers to myocardial injury, detected by a rise in cardiac troponin judged to be of ischaemic origin, occurring during or shortly after non-cardiac surgery; it is often painless and is associated with increased short-term mortality.

Why are perioperative heart attacks often missed?

Sedation, analgesia, and the postoperative state mean that ischaemia frequently causes no chest pain, so many perioperative myocardial injuries are silent and are only identified through routine troponin measurement.