Risk factors and outcome of new-onset cardiac arrhythmias in vascular surgery patients

BACKGROUND

The pathophysiology of new-onset cardiac arrhythmias is complex and may bring about severe cardiovascular complications. The relevance of perioperative arrhythmias during vascular surgery has not been investigated. The aim of this study was to assess risk factors and prognosis of new-onset arrhythmias during vascular surgery.

METHODS

A total of 513 vascular surgery patients, without a history of arrhythmias, were included. Cardiac risk factors, inflammatory status, and left ventricular function (LVF; N-terminal pro-B-type natriuretic peptide and echocardiography) were assessed. Continuous electrocardiography (ECG) recordings for 72 hours were used to identify ischemia and new-onset arrhythmias: atrial fibrillation, sustained ventricular tachycardia, supraventricular tachycardia, and ventricular fibrillation. Logistic regression analysis was applied to identify preoperative risk factors for arrhythmias. Cox regression analysis assessed the impact of arrhythmias on cardiovascular event-free survival during 1.7 years.

RESULTS

New-onset arrhythmias occurred in 55 (11%) of 513 patients: atrial fibrillation, ventricular tachycardia, supraventricular tachycardia, and ventricular fibrillation occurred in 4%, 7%, 1%, and 0.2%, respectively. Continuous ECG showed myocardial ischemia and arrhythmias in 17 (3%) of 513 patients. Arrhythmia was preceded by ischemia in 10 of 55 cases. Increased age and reduced LVF were risk factors for the development of arrhythmias. Multivariate analysis showed that perioperative arrhythmias were associated with long-term cardiovascular events, irrespective of the presence of perioperative ischemia (hazard ratio 2.2, 95% CI 1.3-3.8, P = .004).

CONCLUSION

New-onset perioperative arrhythmias are common after vascular surgery. The elderly and patients with reduced LVF show arrhythmias. Perioperative continuous ECG monitoring helps to identify this high-risk group at increased risk of cardiovascular events and death.

Process of care partly explains the variation in mortality between hospitals after peripheral vascular surgery

OBJECTIVES

The aim of this study is to investigate whether variation in mortality at hospital level reflects differences in quality of care of peripheral vascular surgery patients.

DESIGN

Observational study.

MATERIALS

In 11 hospitals in the Netherlands, 711 consecutive vascular surgery patients were enrolled.

METHODS

Multilevel logistic regression models were used to relate patient characteristics, structure and process of care to mortality at 1 year. The models were constructed by consecutively adding age, sex and Lee index, then remaining risk factors, followed by structural measures for quality of care and finally, selected process of care parameters.

RESULTS

Total 1-year mortality was 11%, ranging from 6% to 26% in different hospitals. Large differences in patient characteristics and quality indicators were observed between hospitals (e.g., age>70 years: 28-58%; beta-blocker therapy: 39-87%). Adjusted analyses showed that a large part of variation in mortality was explained by age, sex and the Lee index (Akaike's information criterion (AIC)=59, p<0.001). Another substantial part of the variation was explained by process of care (AIC=5, p=0.001).

CONCLUSIONS

Differences between hospitals exist in patient characteristics, structure of care, process of care and mortality. Even after adjusting for the patient population at risk, a substantial part of the variation in mortality can be explained by differences in process measures of quality of care.

Health-related quality of life predicts long-term survival in patients with peripheral artery disease

We examined whether health-related quality of life (HRQoL) predicts long-term survival in patients with peripheral artery disease (PAD) independent of established prognostic risk factors. In 2004, data on 711 consecutive patients with PAD undergoing vascular surgery were collected from 11 hospitals in The Netherlands. After 1 year, patients were contacted to complete the EuroQol Questionnaire (EQ-5D), of which 503 complied. HRQoL assessed by the EQ-5D was divided into tertiles (i.e. poor, intermediate and good HRQoL). Mortality was subsequently assessed 3 years after surgery. Of the 503 patients, 55 (11%) patients died during follow-up. Mortality was 21% in patients with poor HRQoL, 8% in patients with intermediate HRQoL, and 5% in patients with good HRQoL. Patients with poor HRQoL (HR = 5.4; 95% CI 2.3—12.5) had a worse survival compared to patients with a good HRQoL, after adjusting for established prognostic factors. In conclusion, the study indicates that poor HRQoL predicts long-term survival in patients with PAD, and provides prognostic value above established risk factors.

Single-photon emission computed tomography for assessment of myocardial viability

Left ventricular dysfunction in patients with chronic coronary artery disease may be a result of dysfunctional but viable myocardium due to myocardial hibernation. Coronary revascularisation may substantially improve regional and global left ventricular dysfunction and long-term survival if a substantial amount of dysfunctional but viable myocardium is present. Because coronary revascularisation, by percutaneous coronary intervention or coronary bypass surgery, is associated with an increased periprocedural risk in patients with severe left ventricular dysfunction, careful preprocedural selection is needed. Assessment of myocardial viability with SPECT may facilitate clinical decision making and should be considered in patients with ischaemic left ventricular dysfunction who are eligible for coronary revascularisation. The most frequently used SPECT protocols use thallium-201 (201Tl) rest-redistribution, technetium-99m (99mTc) labelled viability tracers, or 18F-fluorodeoxyglucose (FDG) for assessment of myocardial glucose metabolism. Approximately 50% of the patients with ischaemic left ventricular dysfunction have a substantial amount of dysfunctional but viable myocardium on SPECT and should be considered for coronary revascularisation. The absence of myocardial viability can help to identify patients who will not benefit from high-risk percutaneous coronary interventions or surgery.

Temporary perioperative decline of renal function is an independent predictor for chronic kidney disease

BACKGROUND AND OBJECTIVES

Acute kidney injury is an independent predictor of short- and long-term survival; however, data on the relationship between reversible transitory decline of kidney function and chronic kidney disease (CKD) are lacking. We assessed the prognostic value of temporary renal function decline on the development of long-term CKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

The study included 1308 patients who were undergoing major vascular surgery (aortic aneurysm repair, lower extremity revascularization, or carotid surgery), divided into three groups on the basis of changes in Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) estimated GFR (eGFR) on days 1, 2, and 3 after surgery, compared with baseline: Group 1, improved or unchanged (change in CKD-EPI eGFR+/-10%); group 2, temporary decline (decline>10% at day 1 or 2, followed by complete recovery within 10% to baseline at day 3); and group 3, persistent decline (>10% decrease). Primary end point was the development of incident CKD during a median follow-up of 5 years.

RESULTS

Perioperative renal function was classified as unchanged, temporary decline, and persistent decline in 739 (57%), 294 (22%), and 275 (21%) patients, respectively. During follow-up, 272 (21%) patients developed CKD. In multivariate logistic regression analyses, temporary and persistent declines in renal function both were independent predictors of long-term CKD, compared with unchanged renal function.

CONCLUSION

Vascular surgery patients have a high incidence of temporary and persistent perioperative renal function declines, both of which were independent predictors for development of long-term incident CKD.

Clinical review: practical recommendations on the management of perioperative heart failure in cardiac surgery

Acute cardiovascular dysfunction occurs perioperatively in more than 20% of cardiosurgical patients, yet current acute heart failure (HF) classification is not applicable to this period. Indicators of major perioperative risk include unstable coronary syndromes, decompensated HF, significant arrhythmias and valvular disease. Clinical risk factors include history of heart disease, compensated HF, cerebrovascular disease, presence of diabetes mellitus, renal insufficiency and high-risk surgery. EuroSCORE reliably predicts perioperative cardiovascular alteration in patients aged less than 80 years. Preoperative B-type natriuretic peptide level is an additional risk stratification factor. Aggressively preserving heart function during cardiosurgery is a major goal. Volatile anaesthetics and levosimendan seem to be promising cardioprotective agents, but large trials are still needed to assess the best cardioprotective agent(s) and optimal protocol(s). The aim of monitoring is early detection and assessment of mechanisms of perioperative cardiovascular dysfunction. Ideally, volume status should be assessed by 'dynamic' measurement of haemodynamic parameters. Assess heart function first by echocardiography, then using a pulmonary artery catheter (especially in right heart dysfunction). If volaemia and heart function are in the normal range, cardiovascular dysfunction is very likely related to vascular dysfunction. In treating myocardial dysfunction, consider the following options, either alone or in combination: low-to-moderate doses of dobutamine and epinephrine, milrinone or levosimendan. In vasoplegia-induced hypotension, use norepinephrine to maintain adequate perfusion pressure. Exclude hypovolaemia in patients under vasopressors, through repeated volume assessments. Optimal perioperative use of inotropes/vasopressors in cardiosurgery remains controversial, and further large multinational studies are needed. Cardiosurgical perioperative classification of cardiac impairment should be based on time of occurrence (precardiotomy, failure to wean, postcardiotomy) and haemodynamic severity of the patient's condition (crash and burn, deteriorating fast, stable but inotrope dependent). In heart dysfunction with suspected coronary hypoperfusion, an intra-aortic balloon pump is highly recommended. A ventricular assist device should be considered before end organ dysfunction becomes evident. Extra-corporeal membrane oxygenation is an elegant solution as a bridge to recovery and/or decision making. This paper offers practical recommendations for management of perioperative HF in cardiosurgery based on European experts' opinion. It also emphasizes the need for large surveys and studies to assess the optimal way to manage perioperative HF in cardiac surgery.

Perioperative cardiac damage in vascular surgery patients

BACKGROUND

Patients undergoing vascular surgery are at increased risk for developing cardiac complications. Majority of patients with perioperative myocardial damage are asymptomatic. Our objective is to review the available literature addressing the prevalence and prognostic implications of perioperative myocardial damage in vascular surgery patients.

METHODS

An Internet-based literature search was performed using MEDLINE to identify all published reports on perioperative myocardial damage in vascular surgery patients. Only those studies published from 2000 to 2010 evaluating myocardial damage using troponin I or T, with or without symptoms of angina pectoris were included.

RESULTS

Thirteen studies evaluating the prevalence of perioperative myocardial ischaemia or infarction were included in the study. The incidence of perioperative myocardial ischaemia ranged from 14% to 47% and the incidence of perioperative myocardial infarction ranged from 1% to 26%. In addition, 10 studies evaluating the prognostic value of perioperative myocardial ischaemia towards postoperative mortality or the occurrence of major adverse cardiac events were included. In the retrieved studies, hazard ratios varied from 1.9 to 9.0.

CONCLUSION

The high prevalence and asymptomatic nature of perioperative myocardial damage, combined with a substantial influence on postoperative mortality of vascular surgery patients, underline the importance of early detection and adequate management of perioperative myocardial damage. This article provides an extended overview regarding the prevalence and prognostic value of perioperative myocardial ischaemia and infarction in vascular surgery patients. In addition, treatment options to reduce the risk of perioperative myocardial damage are provided based on the current available literature.

Relation between regional and global systolic function in patients with ischemic cardiomyopathy after beta-blocker therapy or revascularization

BACKGROUND

To assess the relationship between improved regional and global myocardial function in patients with ischemic cardiomyopathy in response to beta-blocker therapy or revascularization.

MATERIALS AND METHODS

Cardiovascular magnetic resonance (CMR) was performed in 32 patients with ischemic cardiomyopathy before and 8 +/- 2 months after therapy. Patients were assigned clinically to beta-blocker therapy (n = 20) or revascularization (n = 12). CMR at baseline was performed to assess regional and global LV function at rest and under low-dose dobutamine. Wall thickening was analyzed in dysfunctional, adjacent, and remote segments. Follow-up CMR included rest function evaluation.

RESULTS

Augmentation of wall thickening during dobutamine at baseline was similar in dysfunctional, adjacent and remote segments in both patient groups. Therefore, baseline characteristics were similar for both patient groups. In both patient groups resting LV ejection fraction and end-systolic volume improved significantly (p < 0.05) at follow-up. Stepwise multivariate analysis revealed that improvement in global LV ejection fraction in the beta-blocker treated patients was significantly related to improved function of remote myocardium (p < 0.05), whereas in the revascularized patients improved function in dysfunctional and adjacent segments was more pronounced (p < 0.05).

CONCLUSION

In patients with chronic ischemic LV dysfunction, beta-Blocker therapy or revascularization resulted in a similar improvement of global systolic LV function. However, after beta-blocker therapy, improved global systolic function was mainly related to improved contraction of remote myocardium, whereas after revascularization the dysfunctional and adjacent regions contributed predominantly to the improved global systolic function.

Elevated preoperative phosphorus levels are an independent risk factor for cardiovascular mortality

BACKGROUND/AIMS

Serum phosphorus levels have been associated with adverse long-term outcome in several populations, however, no prior studies evaluated short-term postoperative outcome. The present study evaluated the predictive value of phosphorus levels on 30-day outcome after vascular surgery.

METHODS

The study included patients scheduled for major vascular surgery (aortic aneurysm repair, lower extremity revascularization or carotid surgery), divided into four quartiles based on the preoperative fasting phosphorus level. The endpoints of the analyses were all-cause and cardiovascular mortality during the first 30 postoperative days and during long-term follow-up (median 3.6 years, interquartile range 1.8-8.0).

RESULTS

Prior to surgery, 1,798 patients were categorized into the following quartiles: <2.9 mg/dl (n = 459), 2.9-3.4 mg/dl (n = 456), 3.4-3.8 mg/dl (n = 444) and >3.8 mg/dl (n = 439), respectively. During the first 30 postoperative days, 81 (4.5%) patients died of which 66 (81%) secondary to a cardiovascular cause. In multivariate analyses, an independent association was observed between phosphorus level >3.8 mg/dl and all-cause (OR 2.53, 95% CI 1.2-5.4) or cardiovascular mortality (OR 2.37, 95% CI 1.1-5.7). Baseline serum phosphorus >3.8 mg/dl was also significantly associated with long-term all-cause mortality (HR 1.38, 95% CI 1.1-1.7).

CONCLUSIONS

Preoperative elevated serum phosphorus demonstrated an independent relationship with the occurrence of all-cause and cardiovascular mortality during the first 30 days after major vascular surgery. In addition, an elevated serum phosphorus was independently associated with long-term mortality.

Impact of prophylactic beta-blocker therapy to prevent stroke after noncardiac surgery

beta Blockers are widely used to improve the postoperative cardiac outcome in patients with coronary artery disease scheduled for noncardiac surgery. However, recently serious concerns regarding the safety of perioperative beta blockers have emerged. To assess the incidence, risk factors, and beta-blocker use associated with postoperative stroke in the Dutch Echocardiographic Cardiac Risk Evaluation Applying Stress Echocardiography (DECREASE) trials, we evaluated all 3,884 patients of the DECREASE trials for postoperative stroke. All cardiac risk factors and medication use were assessed. The incidence of stroke within 30 days after surgery was recorded. The incidence of postoperative stroke in the DECREASE trials was 0.46% (18 of 3,884). For the beta-blocker users, the incidence was 0.5%. All the strokes had an ischemic origin. A history of stroke was associated with a greater incidence of postoperative stroke (odds ratio [OR] 3.79, 95% confidence interval [CI] 1.2 to 11.6). Statins and anticoagulants were not associated with postoperative stroke (OR 0.85, 95% CI 0.3 to 2.4; and OR 1.27, 95% CI 0.4 to 4.6, respectively). No association with bisoprolol therapy was found (OR 1.16, 95% CI 0.4 to 3.4). In conclusion, with a low-dose bisoprolol regimen started > or =30 days before surgery, no association was observed between beta-blocker use and postoperative stroke.