New-onset atrial dysrhythmias such as atrial fibrillation can occur at any time in the hospital setting and are associated with longer hospital stays and increased mortality. New-onset postoperative atrial dysrhythmias manifest in up to 10% of major noncardiac surgeries. This incidence is even higher after cardiac and thoracic procedures, where the dysrhythmia is often attributed to atrial irritation.1 Many underlying causes can precipitate new-onset atrial fibrillation, including hypertension, coronary and valvular heart disease, heart failure, hypertrophic cardiomyopathy, deep venous thrombosis, pulmonary embolism, and hyperthyroidism.2,3 Every incident of new-onset atrial fibrillation necessitates thorough evaluation. Written consent was obtained from the patient for publication of this case report.
An 82-year-old man presented to the hospital for an elective left total knee replacement. His medical history included hypertension, hyperlipidemia, renal cell carcinoma, and pulmonary embolism. The pulmonary embolism occurred 2 years earlier in the postoperative period after right partial nephrectomy. The patient subsequently received warfarin for 6 months. His surgical history included a right partial nephrectomy, a tonsillectomy, and right total knee replacement.
The patient underwent a preoperative evaluation 2 weeks before the left knee replacement that consisted of a normal electrocardiogram (ECG) and a negative pharmacologic stress test. The only change to the patient’s medication regimen was the discontinuation of his daily 81 mg aspirin 10 days before his scheduled surgery.
On the day of surgery, in the preanesthesia holding unit, the patient was monitored according to our hospital’s standard protocol including 3-lead ECG, noninvasive blood pressure cuff, and pulse oximeter. The anesthesiologist noticed atrial fibrillation on the monitor, which was confirmed by a 12-lead ECG. The ECG is shown in Figure 1. The anesthesiologist contacted the primary care physician who had performed the patient’s preoperative evaluation and confirmed that the patient had no history of atrial fibrillation.
The anesthesiologist and the orthopedic surgeon conferred and agreed to postpone the surgery. The patient was sent promptly to the emergency room, after which he was admitted to a general medical floor where a cardiologist evaluated him. Coagulation studies were performed with the results of prothrombin time 12.3 seconds, international normalized ratio 0.88, and partial thromboplastin time 29.2 seconds. The patient remained asymptomatic throughout the entire process; he did not complain of chest pain or shortness of breath and did not exhibit signs of calf tenderness or lower extremity edema.
A 2-dimensional echocardiogram showed a severely enlarged right ventricle and an acute pulmonary embolus in the right segmental artery, with overall preserved left ventricular systolic function. The echocardiogram is shown in Figure 2. The patient also had a computed tomographic angiography study that confirmed the presence of an acute pulmonary embolus. The patient was subsequently started on heparin and warfarin, with the plan for him to continue lifelong anticoagulation. The patient remained asymptomatic with stable vital signs throughout his inpatient stay and was discharged 3 days after admission. The plan is for the patient to have his originally planned elective left total knee replacement next year.
Venous thromboembolic disease, which includes pulmonary embolism and deep vein thrombosis, is associated with an increased risk of atrial fibrillation. The incidence of atrial fibrillation in patients has been reported to be 10% to 14% in patients with a documented pulmonary embolus.4,5 The mechanism is unknown but has been speculated to be related to atrial strain because of increases in pulmonary vascular resistance and cardiac afterload.6 Pulmonary embolus is associated with significant morbidity and mortality.7,8 For example, the incidence of intraoperative pulmonary embolus in patients undergoing hip surgery is approximately 2%. Pulmonary embolus is associated with a fatal outcome in almost half of those 2% of cases.9
Advanced age is associated with an increased risk of surgical complications, including mortality. Patients older than 80 years have a significantly higher mortality rate than those younger than 80 years for noncardiac surgery. In patients older than 80 years who developed one or more complications, the 30-day mortality rate was 26% vs 4% in patients without a complication.10 A prospective cohort study on surgical outcomes for patients 80 years of age and older determined that for every year >80 there is a 5% increase in 30-day mortality risk.10
This case emphasizes the importance of diligent monitoring and vigilance throughout the entire perioperative process. The preoperative ECG monitoring and diagnosis of atrial fibrillation in this patient led to the discovery and treatment of a pulmonary embolus, thereby avoiding the possibility of significant intraoperative morbidity and mortality. Given that the patient was asymptomatic and had a negative cardiac workup, the atrial fibrillation rhythm easily could have been missed. The problem might have been recognized only after anesthesia was induced, with the patient having an unrecognized pulmonary embolus at a critical juncture. This case also highlights the importance of understanding that a negative cardiac workup does not equal zero cardiac risk. The patient had a negative preoperative workup by his primary care physician, but just 2 weeks later the patient presented with an asymptomatic, new-onset pulmonary embolus. All anesthesiologists must practice with a questioning attitude and perform due diligence throughout all phases of perioperative care. This case reiterates the central role played by the anesthesiologist in the perioperative surgical home model of care.
1. Vaporciyan AA, Correa AM, Rice DC, Roth JA, Smythe WR, Swisher SG, Walsh GL, Putnam JB Jr. Risk factors associated with atrial fibrillation after noncardiac thoracic surgery: analysis of 2588 patients. J Thorac Cardiovasc Surg. 2004;127:779–86
2. Asirvatham SJ, Jiao Z. What causes atrial fibrillation and why do we fail with ablation?: insights from metabolic syndrome. J Am Coll Cardiol. 2012;59:1302–3
3. Chugh SS, Blackshear JL, Shen WK, Hammill SC, Gersh BJ. Epidemiology and natural history of atrial fibrillation: clinical implications. J Am Coll Cardiol. 2001;37:371–8
4. Weber DM, Phillips JH Jr. A re-evaluation of electrocardiographic changes accompanying acute pulmonary embolism. Am J Med Sci. 1966;251:381–98
5. Goldhaber SZ, Visani L, De Rosa M. Acute pulmonary embolism: clinical outcomes in the International Cooperative Pulmonary Embolism Registry (ICOPER) Lancet. 1999;353:1386–9
6. Hald EM, Enga KF, Løchen ML, Mathiesen EB, Njølstad I, Wilsgaard T, Braekkan SK, Hansen JB. Venous thromboembolism increases the risk of atrial fibrillation: the Tromso study. J Am Heart Assoc. 2014;3:e000483
7. Tortosa JA, Hernández-Palazón J. Fatal massive intra-operative pulmonary embolism while placing a patient in the surgical position. Eur J Anaesthesiol. 1999;16:350
8. Chen HL, Wong CS, Ho ST, Chang FL, Hsu CH, Wu CT. A lethal pulmonary embolism during percutaneous vertebroplasty. Anesth Analg. 2002;95:1060–2
9. Koessler MJ, Fabiani R, Hamer H, Pitto RP. The clinical relevance of embolic events detected by transesophageal echocardiography during cemented total hip arthroplasty: a randomized clinical trial. Anesth Analg. 2001;92:49–55
10. Hamel MB, Henderson WG, Khuri SF, Daley J. Surgical outcomes for patients aged 80 and older: morbidity and mortality from major noncardiac surgery. J Am Geriatr Soc. 2005;53:424–9