External validity of a model to predict postoperative atrial fibrillation after thoracic surgery

Abstract

OBJECTIVES A prediction model developed by Passman et al. stratifies patients’ risk of postoperative atrial fibrillation (POAF) after major non-cardiac thoracic surgery using 3 simple factors (sex, age and preoperative resting heart rate). The model has neither undergone external validation nor proven to be relevant in current thoracic surgery practice. METHODS A retrospective single-centre analysis of all patients who underwent major non-cardiac thoracic surgery (2008–2017) with prospective documentation of incidence and severity of POAF was used for external validation of Passman’s derivation sample (published in 2005 with 856 patients). The model calibration was assessed by evaluating the incidence of POAF and patients’ risk scores (0–6). RESULTS A total of 2054 patients were included. Among them, POAF occurred in 164 (7.9%), compared to 147 (17.2%) in Passman’s study. Differences in our sample compared to Passman’s sample included mean heart rate (75.7 vs 73.7 bpm, P < 0.001), proportion of patients with hypertension (46.1 vs 29.4%, P < 0.001), proportion of extensive lung resections, particularly pneumonectomy (6.1 vs 21%, P < 0.001) and proportion of minimally invasive surgeries (56.6% vs 0%). The model demonstrated a positive correlation between risk scores and POAF incidence (risk score 1.2% vs 6.16%). CONCLUSIONS The POAF model demonstrated good calibration in our population, despite a lower overall incidence of POAF compared to the derivation study. POAF rates were higher among patients with a higher risk score and undergoing procedures with greater intrathoracic dissection. This tool may be useful in identifying patients who are at risk of POAF when undergoing major thoracic surgery and may, therefore, benefit from targeted prophylactic therapy.

Resting heart rate as a preoperative predictor of postoperative atrial fibrillation after pulmonary thromboendarterectomy

“…Furthermore, as a marker of the autonomic nervous system, resting heart rate was associated with incident AF, 12,13 which played an important role in the pathological mechanism of AF 31,32 . A predictive model for POAF constituted by three simple parameters, including resting heart rate, showed well efficacy in both internal and external validation cohorts 9,10 . However, the predictive value of resting heart rate for POAF after PTE has not been adequately studied.…”

“…Several risk factors, including age, male sex, and previous history of AAs, have been reported to be associated with AA after PTE 7 . It is well known that the resting heart rate is also a risk factor for POAF 9,10 . However, its role in predicting POAF after PTE has not been well investigated.…”

Prophylaxis for patients at Risk to Eliminate Post-operative Atrial Fibrillation (PREP-AF trial): a protocol for a feasibility randomized controlled study

“…This study is also the first to trial the concept of individualized prophylactic therapy targeted to high-risk individuals. We can identify individuals with a 4-fold increase of POAF who account for 51% of POAF cases using three simple factors available preoperatively [17]. Giving prophylactic amiodarone to only those high-risk individuals demonstrates an opportunity to optimize the benefits of prophylactic amiodarone and avoid unnecessary harm in individuals with low probability of developing POAF.…”

“…In reviewing the literature for risk stratification tools to predict POAF after thoracic surgery, we only identified one which was internally validated for all patients undergoing major thoracic surgery and contained factors obtainable in the preoperative period (resting heart rate, gender, and age) [4,15,16]. After evaluation of this tool at our institution in a sample of 2036 patients undergoing major thoracic surgery between 2008 and 2018, we found it to also be externally valid [17]. To facilitate identifying potential candidates for prophylaxis, we translated this POAF risk model into a designation of high vs low risk.…”

The role of surgery type in postoperative atrial fibrillation and in-hospital mortality in esophageal cancer patients with preserved left ventricular ejection fraction

“…For example, several studies investigating postoperative complications of MIE grouped POAF with other cardiovascular complications together [11][12][13]. Other studies evaluating POAF risk as a single outcome yielded inconsistent results [14][15][16][17]: while one study reported decreased POAF risk after MIE [18], other studies did not find any association between MIE and POAF [16,19]. Another gap in the literature is the lack of consistent short-term mortality rate data after MIE.…”