Preoperative cardiac evaluation of the vascular surgery patient--an anesthesia perspective

Endovascular Treatment of Complex Aorto-Iliac Atherosclerotic Occlusive Disease With Chimney Covered Endovascular Reconstruction of Aortic Bifurcation

Treatment of atherosclerotic occlusive disease of the infrarenal aorta poses several challenges. Traditionally, open surgery has been the preferred method of treatment in standard risk patients, although, it is burdened by high morbidity and mortality. There are many classifications to establish the patient risk for surgery. Among the most common is the American College of Cardiology (ACC)/American Heart Association (AHA) classification. ACC/AHA high-risk patients benefit from the increase in endovascular technology and skills. The treatment modality of atherosclerotic aortic disease has shifted towards a minimally invasive approach, including kissing stents, covered endovascular reconstruction of the aortic bifurcation (CERAB) and, aorto-uniiliac stent grafts. When there is an involvement of vital branches such as the inferior mesenteric (with concomitant occluded superior mesenteric artery) or the renal arteries, Chimney- CERAB technique has been successfully utilized to overcome this challenge. We present three patients with aortoiliac occlusive disease (AIOD) successfully treated with the chimney- CERAB technique to preserve a large inferior mesenteric artery in the setting of occlusion/near occlusion of the other mesenteric vessels.

Anesthetic Management for Endovascular Repair of Thoracic and Abdominal Aortic Aneurysms

Aortic aneurysms-both abdominal and thoracic-are a significant cause of death and disability in the United States. Endovascular aneurysm repair has since become the preferred operative treatment of most thoracic and abdominal aneurysms because of a lower rate of complications and better outcomes compared with the open approach. Patients who present for endovascular aneurysm repair often have comorbid conditions related to their aortic pathology. These conditions should be evaluated and optimized before the procedure.

Cholinesterase activity in serum during general anesthesia in patients with or without vascular disease

Maintaining hemodynamic stability during the induction and maintenance of anesthesia is one of the challenges of the anesthesiologist. Patients with vascular disease are at increased risk of instability due to imbalance between the sympathetic and parasympathetic parts of the autonomic nervous system, a balance accessible by serum cholinesterase activity. We aim to characterize the dynamics of cholinesterase activity in patients undergoing general anesthesia (GA) and surgery. This was a prospective study of 57 patients undergoing ambulatory or vascular surgery under GA. Cholinesterase activity was measured before the induction of anesthesia, after 15 min and at the end of surgery by calculating the capacity of serum acetylcholinesterase (AChE) and butyrylcholinesterase to hydrolyze AcetylThioCholine. Data on atherosclerotic disease, anesthesia management were analyzed. Both AChE and total cholinergic status (CS) decreased significantly after GA induction at 15 min and even more so by the end of surgery. Vascular surgery patients had lower baseline cholinesterase activity compared to ambulatory surgery patients. Patients requiring intraoperative administration of phenylephrine for hemodynamic support (21.1%) had a significantly lower level of AChE and CS compared to untreated patients. Our findings serve as a mirror to the sympathetic/parasympathetic imbalance during GA, with a marked decrease in the parasympathetic tone. The data of a subgroup analysis show a correlation between low cholinesterase activity and an increase in the need for hemodynamic support.

Optimal perioperative medical management of the vascular surgery patient

Perioperative medical management of patients undergoing vascular surgery can be challenging because they represent the surgical population at highest risk. β-Blockers should be continued perioperatively in patients already taking them preoperatively. Statins may be used in the perioperative period in patients who are not on statin therapy preoperatively. Institutional guidelines should be used to guide insulin replacement. Recent research suggests that measurement of troponins may provide some risk stratification in clinically stable patients following vascular surgery. Multimodal pain therapy including nonopioid strategies is necessary to improve the efficacy of pain relief and decrease the risk of side effects and complications.

Role of cardiac evaluation before thoracic endovascular aortic repair

BACKGROUND

Patients with thoracic aortic disease undergoing thoracic endovascular aortic repair (TEVAR) often have concomitant coronary artery disease and are at risk for perioperative adverse cardiac events. Despite this risk, the need for and extent of preoperative cardiac workup before TEVAR remain undefined. This study seeks to assess the adequacy of a limited cardiac evaluation before TEVAR, including assessment of cardiac symptoms, resting electrocardiography (ECG), and transthoracic echocardiography (TTE), as well as to estimate the incidence of perioperative cardiac events in patients undergoing TEVAR.

METHODS

Retrospective analysis of a prospectively maintained Institutional Review Board-approved database was performed for all patients undergoing TEVAR at a single referral institution between May 2002 and June 2013. The analysis identified 463 TEVAR procedures. All procedures involving median sternotomy were excluded, and 380 procedures (343 patients) were included in the final analysis. Degree of cardiac workup was classified on the basis of the highest level of preoperative testing: no workup, resting ECG only, resting TTE, exercise/pharmacologic stress testing, or coronary angiography. Standard workup consisted of cardiac symptom assessment along with resting ECG or TTE, with further workup indicated for unstable symptoms, significantly abnormal findings on ECG or TTE, or multiple cardiac risk factors. Categorical and continuous variables were compared by Fisher's exact test and analysis of variance, respectively.

RESULTS

No preoperative cardiac workup was performed for 28 patients (7.4%); 127 patients (33.4%) had resting ECG only, 208 patients (54.7%) had resting echocardiography, 12 patients (3.2%) underwent stress testing, and five patients (1.3%) had coronary angiography. Patients undergoing stress testing or coronary angiography were older and had a higher incidence of known coronary artery disease (P < .01) and prior myocardial infarction (P = .01). Complex hybrid aortic repairs and TEVAR for aneurysmal disease were more likely to have an extensive workup, whereas nonelective procedures more commonly had no workup. A total of nine patients (2.4%) experienced a perioperative cardiac event (myocardial infarction or cardiac arrest), with no significant difference noted among all groups (P = .45), suggesting that the extent of cardiac workup was appropriate. The incidence of 30-day/in-hospital mortality (5.5%) and cardiac-specific mortality (0.8%) was similar among all groups.

CONCLUSIONS

The risk of a postoperative cardiac event after TEVAR is low (2.4%), and initial screening with either resting TTE or ECG, in addition to assessment of cardiac symptom status, appears adequate for most TEVAR patients. As such, we recommend resting TTE or ECG as the initial cardiovascular screening mechanism in patients undergoing TEVAR, with subsequent more invasive studies if initial screening reveals cardiovascular abnormalities.