Preoperative Statin Use Not Associated With Improved Outcomes After Ascending Aortic Repair

Research advances in drug therapy for abdominal aortic aneurysms over the past five years: An updated narrative review

BACKGROUND

Abdominal aortic aneurysms (AAA) rupture can lead to patient death. Surgical treatment is currently the optimal treatment for AAA with large diameter (≥50 mm). For AAA with small diameter (30-50 mm), how to administer effective pharmacological treatment to reduce aneurysm expansion rate and rupture risk is the current focus in the field of vascular surgery. There is still no effective drug for the treatment of asymptomatic AAA.

METHODS

This article searches the PubMed, Web of Science, Embase, and Cochrane databases for clinical studies on the drug treatment of abdominal aortic aneurysms in the past 5 years. The latest progress in the drug treatment of AAA was reviewed, including antibiotics, antihypertensive drugs, antiplatelet drugs, hypoglycemic drugs, hypolipidemic drugs, mast cell inhibitors and corticosteroids.

RESULTS

25 studies were included in this narrative review. Among them, metformin revealed therapeutic effect in 2 prospective cohort study and 3 retrospective cohort study. The therapeutic effect of statins was controversial in 3 retrospective cohort study. However, the definite therapeutic effects of antihypertensive agents, antibiotics, mast cell inhibitors, antiplatelet agents and corticosteroids on abdominal aortic aneurysms have not been verified in prospective studies.

CONCLUSION

Metformin provided a positive effect in reducing expansion rate, rupture risk, and perioperative mortality. The therapeutic effect of statins was controversial, which warrant further validation in prospective cohorts. However, there is still a lack of effective agents for the treatment of AAA based on recent studies.

The effect of preoperative statins on postoperative mortality, renal, and neurological complications in patients undergoing cardiac surgeries: a retrospective cohort study

BACKGROUND

Cardiac surgery is performed worldwide to treat severe cases of cardiovascular diseases. Statins have shown controversial effects on complications after cardiac surgeries. We aimed to investigate the effect of preoperative statin therapy on the frequency of postoperative mortality, renal, and neurological complications.

METHODS

In a retrospective cohort study, the database of patients operated on in two hospitals in southern Iran during 2008-2019 was used to compare preoperative statin use with no use on the composite outcome of mortality, renal, and neurological complications as well as on each component of the composite, separately. Effects of low dose (<40 mg simvastatin equivalence) vs. high dose (≥40 mg) statins were also evaluated. Confounders that could affect the outcomes were considered in the logistic regression model, and multiple imputation techniques were used to categorize patients with unknown statin dose use as either high or low-dose users.

RESULTS

Of total 7329 patients, 17.6% of statin users and 17% of non-statin users developed the composite outcome (P=0.51). Statin use had no statistically significant association with the composite outcome (aRR 1.01 [95% CI: 0.88-1.16]). There was no significant association with mortality [aRR: 0.75 (95% CI: 0.34-1.69)], neurological [aRR: 1.25 (95% CI: 0.77-2.12)], or renal complications [aRR: 1.03 (95% CI 0.90-1.19)] after surgery. Neither low nor high doses had any statistically significant effect on the composite or any of its components.

CONCLUSIONS

In this large study, preoperative statin use, either high dose or low dose, did not affect short-term postoperative mortality, neurological, or renal complications.

Atrial nitroso-redox balance and refractoriness following on-pump cardiac surgery: a randomized trial of atorvastatin

AIMS

Systemic inflammation and increased activity of atrial NOX2-containing NADPH oxidases have been associated with the new onset of atrial fibrillation (AF) after cardiac surgery. In addition to lowering LDL-cholesterol, statins exert rapid anti-inflammatory and antioxidant effects, the clinical significance of which remains controversial.

METHODS AND RESULTS

We first assessed the impact of cardiac surgery and cardiopulmonary bypass (CPB) on atrial nitroso-redox balance by measuring NO synthase (NOS) and GTP cyclohydrolase-1 (GCH-1) activity, biopterin content, and superoxide production in paired samples of the right atrial appendage obtained before (PRE) and after CPB and reperfusion (POST) in 116 patients. The effect of perioperative treatment with atorvastatin (80 mg once daily) on these parameters, blood biomarkers, and the post-operative atrial effective refractory period (AERP) was then evaluated in a randomized, double-blind, placebo-controlled study in 80 patients undergoing cardiac surgery on CPB. CPB and reperfusion led to a significant increase in atrial superoxide production (74% CI 71-76%, n = 46 paired samples, P < 0.0001) and a reduction in atrial tetrahydrobiopterin (BH4) (34% CI 33-35%, n = 36 paired samples, P < 0.01), and in GCH-1 (56% CI 55-58%, n = 26 paired samples, P < 0.001) and NOS activity (58% CI 52-67%, n = 20 paired samples, P < 0.001). Perioperative atorvastatin treatment prevented the effect of CPB and reperfusion on all parameters but had no significant effect on the postoperative right AERP, troponin release, or NT-proBNP after cardiac surgery.

CONCLUSION

Perioperative statin therapy prevents post-reperfusion atrial nitroso-redox imbalance in patients undergoing on-pump cardiac surgery but has no significant impact on postoperative atrial refractoriness, perioperative myocardial injury, or markers of postoperative LV function.

CLINICAL TRIAL REGISTRATION

https://clinicaltrials.gov/ct2/show/NCT01780740.

Statin Therapy in Patients Undergoing Thoracic Aorta Replacement for Aortic Aneurysms

Background  Patients undergoing surgery for thoracic aortic aneurysms receive statin therapy out of proportion to cardiovascular comorbidity. We sought to determine the prevalence of statin use among patients presenting for thoracic aortic aneurysm surgery and investigate its effect on outcomes.

Methods  From January 1, 2005 to January 1, 2011, 1,839 consecutive patients underwent aortic replacement for degenerative thoracic aortic aneurysm at Cleveland Clinic. Of these, 771 (42%) were on statins preoperatively. Statin users (vs. nonstatin users) were older (65 ± 11 vs. 56 ± 16 years) and had more hypertension (78 vs. 59%). Propensity matching based on 56 preoperative variables other than lipid levels was used to compare outcomes among 570 matched patient pairs (74% of possible pairs).

Results  Propensity-matched statin and nonstatin users were aged 64 ± 11 years, 394 (69%) versus 387 (68%) were male, and 437 (77%) versus 442 (78%) had ascending aortic aneurysms, respectively. Overall, 25% of patients were followed for more than 8.2 years and 10% for more than 10 years. Perioperative outcomes were similar, including hospital mortality (11 [1.9%] vs. 5 [0.88%]) and stroke (22 [3.9%] vs. 13 [2.3%]), but 16 statin users (2.8%) versus 5 nonstatin users (0.88%) required temporary dialysis after surgery ( p  = 0.02). At 6 years, 3.7% of statin users versus 5.1% of nonstatin users ( p [log-rank] = 0.5) underwent further aortic surgery, and at 10 years, mortality was 25% in both groups ( p  > 0.5).

Conclusion  Patients presenting for thoracic aortic aneurysm surgery frequently receive unnecessary statins. Additionally, statin use was associated with more postoperative renal failure, but not less intermediate-term risk for aortic reintervention or all-cause mortality after surgery. Therefore, presence of a thoracic aortic aneurysm should not be considered an indication for statin therapy in the absence of well-established indications.

Preoperative statin therapy is associated with higher 5-year survival after thoracic endovascular aortic repair

OBJECTIVE

Statin use is associated with higher long-term survival after abdominal aortic aneurysm repair. However, the association between statin use and survival after thoracic endovascular aortic repair (TEVAR) has not been established.

METHODS

We performed a review of prospectively collected data of all patients who had undergone TEVAR in the Vascular Quality Initiative between 2014 and 2020. We excluded patients aged <18 years, those who had presented with trauma, and those who had received custom-manufactured or physician-modified devices. We evaluated the association between preoperative statin therapy and in-hospital mortality and complications and 5-year mortality. We also analyzed the trend of preoperative statin use in elective cases for the previous 7 years. To account for nonrandom assignment to treatment, we used propensity score matching of patient characteristics, comorbidities, pathology, and urgency for preoperative statin use. We used logistic regression and Cox regression for the short-term and 5-year outcomes, respectively.

RESULTS

Of 6266 patients who had undergone TEVAR and met the inclusion criteria, 3331 (53%) patients had been taking a statin preoperatively, including 1148 of 2267 (64%) treated for aneurysmal disease. After propensity score matching, 1875 patients were in each cohort. Preoperative statin use was associated with lower rates of any perioperative complication (16.7% vs 19.6%; odds ratio, 0.82; 95% confidence interval [CI] 0.69-0.97; P = .022). Overall, preoperative statin use was also associated with lower 5-year mortality (18.8% vs 24.5%; hazard ratio [HR], 0.74; 95% CI, 0.63-0.89; P = .001). When stratified by urgency, preoperative statin use was associated with lower 5-year mortality after elective TEVAR (14.9% vs 22.4%; HR, 0.62; 95% CI, 0.49-0.79; P < .001) but not after urgent or emergent TEVAR (27.4% vs 29.1%; HR, 0.89; 95% CI, 0.70-1.14; P = .37). When stratified by pathology, preoperative statin use was associated with significantly lower 5-year mortality for patients with aneurysms (HR, 0.63; 95% CI, 0.48-0.83; P = .001). Although the mortality was also lower for patients with dissection and "other" pathology, these differences did not reach statistical significance. Between 2014 and 2019, a significant increase had occurred in statin use among patients undergoing elective TEVAR, from 56% in 2014 to 64% in 2019 (P = .007).

CONCLUSIONS

Preoperative statin therapy is associated with lower perioperative complication rates and 5-year mortality for patients undergoing TEVAR. All patients with known thoracic aortic pathology should receive statin therapy unless contraindications for the drug are present. For patients undergoing elective TEVAR, the statin prescription percentage should be considered a quality metric, and further implementation research should occur to improve preoperative statin use.

Early postoperative statin administration does not affect the rate of atrial fibrillation after cardiac surgery

OBJECTIVES

Postoperative atrial fibrillation is the most frequent complication after cardiac surgery, and the use of statins in preventing them is being extensively studied. The aim of this study was to investigate whether a pause in the administration of statins affects the occurrence of atrial fibrillation after cardiac surgery in a prospective randomized and controlled setting.

METHODS

A total of 301 patients without chronic atrial fibrillation with prior statin medication scheduled for elective or urgent cardiac surgery involving the coronary arteries and/or heart valves were prospectively recruited and randomized for statin re-initiation on either the first (immediate statin group) or the fifth (late statin group) postoperative day, using the original medication and dosage. The immediate statin group comprised 146 patients and the late statin group 155 patients. Except for a somewhat higher rate of males (85% vs 73%, P = 0.016) in the immediate statin group, the baseline characteristics and the distribution of procedures performed within the groups were comparable. The occurrence of postoperative atrial fibrillation and the clinical course of the patients were compared between the groups.

RESULTS

The incidence of atrial fibrillation was 46% and the median delay after surgery before the onset of atrial fibrillation was 3 days in both groups (P = NS). No differences were observed in the frequency of the arrhythmia in any subgroup analyses or in other major complications or clinical parameters. No adverse effects related to early statin administration were detected.

CONCLUSIONS

Early re-initiation of statins does not appear to affect the occurrence of postoperative atrial fibrillation.

CLINICAL TRIAL REGISTRATION

European Union Drug Regulating Authorities Clinical Trials Database (EudraCT)-2016-001655-44.

Perioperative Renoprotection: General Mechanisms and Treatment Approaches

In the perioperative setting, acute kidney injury (AKI) is a frequent complication, and AKI itself is associated with adverse outcomes such as higher risk of chronic kidney disease and mortality. Various risk factors are associated with perioperative AKI, and identifying them is crucial to early interventions addressing modifiable risk and increasing monitoring for nonmodifiable risk. Different mechanisms are involved in the development of postoperative AKI, frequently picturing a multifactorial etiology. For these reasons, no single renoprotective strategy will be effective for all surgical patients, and efforts have been attempted to prevent kidney injury in different ways. Some renoprotective strategies and treatments have proven to be useful, some are no longer recommended because they are ineffective or even harmful, and some strategies are still under investigation to identify the best timing, setting, and patients for whom they could be beneficial. With this review, we aim to provide an overview of recent findings from studies examining epidemiology, risk factors, and mechanisms of perioperative AKI, as well as different renoprotective strategies and treatments presented in the literature.

The influence of statins on aortic aneurysm after operation: A retrospective nationwide study

Aortic aneurysm (AA) is a disease with substantially higher health care costs and very high mortality upon rupture. Statins have a non-lipid-lowering pleiotropic mechanism that may be beneficial for AA in disease progression and improvement of AA patient outcomes. Previous studies have been conducted with some limitations and without considering immortal time bias, lag time, and adherence. The aim of our study was to analyze the effect of statin use on AA postoperation after controlling for these factors.All postoperative patients with a diagnosis of AA in Taiwan from 2004 to 2012 were included from the National Health Insurance Research Database. We excluded patients without computed tomography within 1 year after diagnosis and those who died within 30 days after the operation. We also analyzed the medication, medication possession ratio (MPR), immortal time bias, and lag time. Statin users were defined as those using statins for more than 30 days. Primary composite outcomes included mortality, reoperation for AA and rehospitalization for AA during the study period.Among the whole study population (n = 1633), 199/1633 (12.19%) patients were statin users, while the others (n = 1434) were not. Mortality was higher in statin nonusers than in statin users, with a mortality rate of 40% versus 22.61% (P < .0001). There was no significant difference in reoperation or rehospitalization for AA.Statin use may be beneficial for AA patients in our observational study. Prospective randomized controlled studies are needed to define the effect of statin therapy in this population.