The importance of the appropriate perioperative cardiac management in non-cardiac surgery lies in the high number of surgical procedures performed each year and the related cardiac complications, which account for almost half of the perioperative morbidity. The risk of complications in non-cardiac surgery depends on (1) the type, urgency, and duration of the surgery, and (2) the patient risk factors, including the perioperative condition and comorbidities. Perioperative cardiac management is a process of risk stratification and mitigation and not "cardiac clearance" as is often requested by providers.
Type of Surgery
Regarding cardiac risk, surgical and endovascular procedures may be classified into three categories according to the estimated 30-day cardiac event rates (cardiac death and myocardial infarction) without considering the patient's comorbidities:
Low-Risk (Less Than 1%)
Intermediate-Risk (Between 1% to 5%)
High-Risk (Over 5%)
It is worth noting that procedures involving a laparoscopic approach may be associated with cardiovascular complications, so these patients should undergo a preoperative risk assessment.
Evaluation of Patient-Related Risk Factors
The preoperative cardiac evaluation must be tailored to each particular patient, surgical type, and urgency. History-taking and examination as a first step, including the assessment of functional capacity and risk indices, will allow the practitioner to determine the extent of preoperative cardiac evaluation. Bear in mind that ancillary exams should only be requested if the results would influence patient management. Most "low perioperative cardiac risk" patients can undergo low- and intermediate-risk surgery with only a clinical assessment.
Calculation of Surgical Risk
A validated risk-prediction tool can predict the risk of perioperative major adverse cardiac events (MACE) in patients undergoing non-cardiac surgery. Current risk prediction tools used include:
Several studies have examined the potential utility of including biomarkers to improve the prediction of preoperative risk. The following are the most used biomarkers:
The existing preliminary evidence shows that the increase in troponin T in the perioperative period reflects clinically significant myocardial damage associated with poor cardiac prognosis and surgical outcome. Some studies have shown that high preoperative BNP and NT-proBNP values have independent prognostic significance to predict cardiac events and long-term mortality after non-cardiac vascular surgery. Thus, with the current evidence, the preoperative assessment via biomarkers for patients undergoing non-cardiac surgery cannot be recommended for screening in all patients but these can be considered for high-risk patients (functional capacity less than 4 METs or with an RCRI value greater than 1 for vascular surgery and greater than 2 for non-vascular surgery).
Non-Invasive and Invasive Testing
Myocardial ischemia, valvular heart disease, and ventricular dysfunction are known major determinants of surgical risk. Preoperative non-invasive and invasive testing may be helpful for diagnosis in patients with strong clinical suspicion or to improve the condition in patients with known cardiac diseases. The investigation should be carried out as in patients who will not undergo surgery and should only be undertaken if the expected outcome would change perioperative management or help inform the patient about their options.
Risk-Reduction Strategies: Perioperative Medical Therapy
The evidence currently available shows that preoperative use of beta-blockers was associated with a reduction in cardiac events but not in surgical death. In addition, preoperative use was associated with arterial hypotension, bradycardia, and stroke. Therefore, the following recommendations are made:
Perioperative Statin Therapy
Statins, in addition to their effect on lipids, induce coronary plaque stabilization through pleiotropic effects. This may prevent plaque rupture and subsequent myocardial infarction in the perioperative period. Preliminary evidence supports that preoperative statin use in non-cardiac surgery may decrease mortality and myocardial injury. Besides, some studies have shown that the preoperative statin therapy interruption in a patient within 2 years following stent placement or immediately after aortic surgery may increase the mortality and myocardial injury, respectively. Therefore, the following recommendations are made:
Calcium Channel Blockers
Further evidence is needed to define the value of these drugs during the perioperative period of non-cardiac surgery. Calcium channel blockers should be continued during the perioperative period in patients with vasospastic angina. Heart rate-reducing calcium channel blockers may be considered in patients with beta-blockers adverse effects unless use contraindication.
Angiotensin-Converting Enzyme Inhibitors (ACEIs) and Angiotensin-Receptor Blockers (ARBs)
Currently, there is no significant evidence showing the benefit in continuing the administration of ACEIs or ARBs to patients who will undergo a non-cardiac surgery. The perioperative use of ACEIs or ARBs increase the arterial hypotension risk, and a recent cohort study showed that withdrawal before surgery reduced mortality, stroke and myocardial injury. Therefore, whether the preoperative use of these drugs should be continued or discontinued remains debatable until more evidence is available. If discontinued, the morning before surgery is sufficient time, and it could be resumed after surgery as soon as blood volume and pressure are stable.
In patients with coronary stents or those who have suffered acute coronary syndrome (ACS), the early discontinuation of double antiplatelet therapy (DAPT) significantly increases the risk of thrombosis, and therefore, acute coronary events. In patients with a known cardiovascular disease or a high risk to develop it, even if they do not have coronary stents, the withdrawal of antiplatelet therapy may be associated with the appearance of new cardiac events. On the other hand, the risk of perioperative bleeding is greater in patients who continue to receive aspirin and even higher with DAPT. Therefore, the following recommendations are made:
Thromboembolic risk and the risk of bleeding relative to the type of surgery to be performed should be weighed in each patient treated with anticoagulants. In high thromboembolic risk cases with a low risk of surgical bleeding (e.g., skin surgery), anticoagulant therapy may not be discontinued. In surgeries with a high risk of bleeding, anticoagulants therapy should be discontinued. In these cases, if there is a patient with a high risk of thromboembolic complications, the anticoagulants should be dosed so that the effect remains only until a few hours before surgery.
Risk-Reduction Strategies: Preoperative Cardiac Surgery and Endovascular Procedures
Indications for a surgical or endovascular coronary revascularization in the preoperative period of a non-cardiac surgery are like those in the non-surgical setting. Control of myocardial ischemia before non-cardiac surgery is recommended whenever the operation can be delayed at no risk for the patient. Routine myocardial revascularization in patients without myocardial ischemia is not recommended before non-cardiac surgery exclusively to reduce the risk of perioperative cardiac events.
Since the following valvular heart diseases increase the perioperative risk of cardiac events in non-cardiac surgery, it is reasonable to treat them in advance of non-cardiac surgery to reduce the risk whenever the level of severity mentioned below is reached.
The clinical significance of the proper perioperative cardiac management in non-cardiac surgery lies in the high number of surgical procedures performed each year and the related cardiac complications. Before surgery, the health professional must assess the risk of surgery type and the patient's risk. The patient's risk can be specified through history, examination, and non-invasive and invasive tests. The evaluation of functional capacity and the calculation of surgical risk may be useful in this regard. The preventive approach is pivotal, and if the situation warrants it, risk reduction strategies should be implemented with drugs, surgery, or endovascular procedures.
In patients with true life-threatening surgical issues, operative intervention should not be delayed by ticagrelor or extensive perioperative cardiac management. In patients who continue antiplatelet agents or anticoagulants in the perioperative period, a meticulous surgical technique should be employed to minimize the risk of postoperative bleeding complications.
A primary care physician can often do the preoperative clinical evaluation. However, in patients with symptoms or a history of heart disease, who will undergo moderate or high-risk procedures, it will often be necessary for the cardiologist to perform it.
Before the surgery, the doctor frequently must request electrocardiogram, laboratory tests, stress test, echocardiography, etc., so it is important to him keeping in touch with the technicians and physicians who do them to know their details.
The physician who performs perioperative cardiac management should be in communication with the surgeon, the anesthesiologist, the internist, and the intensivist (if the patient requires intensive care) to achieve the best possible results.
Initiation of preoperative high-dose beta-blockers without titration (in other words, to be initiated on the day of surgery) is not safe. (Level I) Ideally, preoperative beta-blockers should be initiated at least 1 week to 1 month before the surgery, be titrated to a resting heart rate of 55 to 70 beats per minute, and be continued for at least 1 month postoperatively.
Management of the perioperative antiplatelet therapy should be determined by a consensus of the interporfesional team including surgeon, anesthesiologist, cardiologist, and patient.