Characteristics and Outcomes of Type 1 versus Type 2 Perioperative Myocardial Infarction After Noncardiac Surgery

Postoperative Myocardial Infarction after Non-Cardiac Surgery: An Update

Every year, not less than 300 million non-cardiac surgery interventions are performed in the world. Perioperative mortality after non-cardiac surgery is estimated at 2% in patients over 45 years of age. Cardiovascular events account for half of these deaths, and most are due to perioperative myocardial infarction (MINS). The diagnosis of postoperative myocardial infarction, before the introduction of cardiac biomarkers, was based on symptoms and electrocardiographic changes and its incidence was largely underestimated. The incidence of MINS when a standard troponin assay is used ranges between 8 and 19% but increases to 20-30% with high-sensitivity troponin assays. Higher troponin values suggesting myocardial injury, both with or without a definite diagnosis of myocardial infarction, are associated with an increase in 30-day and 1-year mortality. Diagnostic and therapeutic strategies are reported.

Comparison of outcome among type 2 vs type 1 myocardial infarction: a systematic review and meta-analysis

To date, there were limited studies available on myocardial infarction (MI), and consequently, the outcomes of patients with type 1 myocardial infarction (T1MI) compared to type 2 myocardial infarction (T2MI) remained inconclusive. We aimed to compare the outcomes of T1MI and T2MI patients in terms of mortality and adverse cardiovascular outcomes. We performed a systematic literature search on PubMed, Embase, and Scopus for relevant articles from inception until March 20, 2022. 341,049 patients had T1MI, while the remaining 67,537 patients had T2MI. Mean age was similar between both groups (T1MI: 67.3 years, T2MI: 71.03 years), while the proportion of females was lower in T1MI (37.81% vs 47.15%). Our analysis revealed that patients with T1MI had significantly lower odds of all-cause mortality (OR 0.45, 95% CI 0.36-0.56, p < 0.001), in-hospital mortality (OR 0.63, 95% CI 0.46-0.86, p < 0.001), 1-year mortality (OR 0.35, 95% CI 0.25-0.47, p < 0.001), and major adverse cardiovascular events (MACE) (OR 0.59, 95% CI 0.39-0.91, p = 0.02). There was no significant difference in terms of 30-day mortality (OR 0.58, 95% CI 0.25-1.36, p = 0.21), cardiovascular mortality (OR 0.95, 95% CI 0.68-1.32, p = 0.74), all-cause readmission (OR 0.84, 95% CI 0.62-1.14, p = 0.26), and readmission due to MI (OR 1.22, 95% CI 0.66-2.27, p = 0.53) between both groups. Patients with T1MI had favorable outcomes in terms of mortality and MACE compared to that of T2MI patients. Further studies should aim at determining the optimal management strategy for these high-risk patients for better patient outcomes.

Chest pain in patients recovering from noncardiac surgery: A retrospective analysis

STUDY OBJECTIVE

Chest pain is relatively common postoperatively. Myocardial infarction (MI) is one cause of chest pain after surgery, but chest pain also results from less severe conditions. Because of its potential severity, chest pain usually prompts the activation of Rapid Response Systems (RRS). While chest pain is a cardinal symptom of myocardial ischemia in the non-surgical setting, the significance and relevance of chest pain after noncardiac surgery remains unclear.

DESIGN

We conducted a retrospective analysis of noncardiac surgical inpatients for whom postoperative chest pain triggered our multidisciplinary RRS.

SETTING

Surgical wards at Cleveland Clinic, Cleveland, OH.

PATIENTS

Postsurgical patients after noncardiac surgery in whom the RSS system was activated for chest pain.

INTERVENTIONS

RRS specified interventions like ECG readings, troponin measurements, transfer to ICU.

MEASUREMENTS

Our primary outcome was MI. Secondary outcomes included the proportion of patients who had an ECG performed, troponin measurements, echocardiography, cardiac catheterization, and were admitted to the Intensive Care Unit (ICU).

MAIN RESULTS

5850 surgical patients experienced postoperative chest pain and triggered an RRS activation between 2009 and 2019. A total of 3110 patients had troponin T measured within 6 h after RRS activation, and 538 of them (17%) had elevated troponin, meeting the Fourth Universal Definition criteria for MI. Additionally, 2 patients had ST-segment elevation infarction (STEMI) without troponin measurement. Among the 540 patients with MI, only 19 (3.5%) were diagnosed with a STEMI by ECG, 388 (72%) had echocardiography, 43 patients (8%) had cardiac catheterization, 8 patients (1.5%) required emergent cardiac surgery, and 424 (79%) were admitted to an ICU.

CONCLUSION

Chest pain is a serious clinical sign, often indicating a postoperative myocardial infarction, and therefore should be taken seriously. Troponin screening should be routinely considered in postsurgical patients who report chest pain.