Heart rate variables in the Vascular Quality Initiative are not reliable predictors of adverse cardiac outcomes or mortality after major elective vascular surgery

Abstract

Objective Heart rate (HR) parameters are known indicators of cardiovascular complications after cardiac surgery, but there is little evidence of their role in predicting outcome after major vascular surgery. The purpose of this study was to determine whether arrival HR (AHR) and highest intraoperative HR are associated with mortality or major adverse cardiac events (MACEs) after elective vascular surgery in the Vascular Quality Initiative (VQI). Methods Patients undergoing elective lower extremity bypass (LEB), aortofemoral bypass (AFB), and open abdominal aortic aneurysm (AAA) repair in the VQI were analyzed. MACE was defined as any postoperative myocardial infarction, dysrhythmia, or congestive heart failure. Controlled HR was defined as AHR <75 beats/min on operating room arrival. Delta HR (DHR) was defined as highest intraoperative HR – AHR Procedure-specific MACE models were derived for risk stratification, and generalized estimating equations were used to account for clustering of center effects. HR, beta-blocker exposure, cardiac risk, and their interactions were explored to determine association with MACE or 30-day mortality. A Bonferroni correction with P < .004 was used to declare significance. Results There were 13,291 patients reviewed (LEB, n = 8155 [62%]; AFB, n = 2629 [18%]; open AAA, n = 2629 [20%]). Rates of any preoperative beta-blocker exposure were as follows: LEB, 66.5% (n = 5412); AFB, 57% (n = 1342); and open AAA, 74.2% (n = 1949). AHR and DHR outcome association was variable across patients and procedures. AHR <75 beats/min was associated with increased postoperative myocardial infarction risk for LEB patients across all risk strata (odds ratio [OR], 1.4; 95% confidence interval [CI], 1.03–1.9; P = .03), whereas AHR<75 beats/min was associated with decreased dysrhythmia risk (OR, 0.42; 95% CI, 0.28–0.63; P = .0001) and 30-day death (OR, 0.50; 95% CI, 0.33–0.77; P = .001) in patients at moderate and high cardiac risk. These HR associations disappeared in controlling for beta-blocker status. For AFB and open AAA repair patients, there was no significant association between AHR and MACE or 30-day mortality, irrespective or cardiac risk or beta-blocker status. DHR and extremes of highest intraoperative HR (>90 or 100 beats/min) were analyzed among all three operations, and no consistent associations with MACE or 30-day mortality were detected. Conclusions The VQI AHR and highest intraoperative HR variables are highly confounded by patient presentation, operative variables, and beta-blocker therapy. The discordance between cardiac risk and HR as well as the lack of consistent correlation to outcome makes them unreliable predictors. The VQI has elected to discontinue collecting AHR and highest intraoperative HR data, given insufficient evidence to suggest their importance as an outcome measure.

Major Cardiac Events in Patients Admitted to Intensive Care After Vascular Noncardiac Surgery: A Retrospective Cohort

“…van Lier et al 1 described tachycardia, anemia, hypoxemia, and hypotension as contributors to myocardial injury because of a supply and demand mismatch. We found mechanical ventilation and heart rate at admission to ICU as independent risk factors for MACE after VS. Scali et al 18 reported less mortality when heart rate was less than 75 beats per minute, but the effect disappeared after controlling for β-blocker therapy. Unfortunately, it was impossible to determine β-blocker therapy in our sample.…”

Systematic Review and Meta-analysis of Factors Influencing Survival Following Abdominal Aortic Aneurysm Repair

“…Sometimes clinical variables collected in operative registries have no clinical value and can lead to incomplete datasets. 60 This analysis has also identified important demographic and clinical factors that influence late survival and such factors should be considered in predictive late survival modelling tools and clinical decision making. 35,54 Varying definitions of major co-morbidities, such as cardiac failure and COPD in published studies, markedly hinder the evaluation of the influence of these conditions on outcomes such as long-term survival after AAA repair.…”

The effects of preoperative cardiology consultation prior to elective abdominal aortic aneurysm repair on patient morbidity

“…16 Additionally, another study suggested that for open AAA repair patients, there was no significant association between arrival heart rate and major adverse cardiac events or 30-day mortality, irrespective of cardiac risk or beta-blocker status. 17 These data call into question whether preoperative cardiology consultation can even modify the factors that have recently been shown to increase perioperative adverse cardiac events and mortality, and that interventions implemented due to cardiology consultation may not benefit patients in this cohort.…”