Carotid artery stenosis as an independent risk factor for perioperative strokes following mitral valve surgical intervention

The evolution of technical prerequisites and local boundary conditions for optimization of mitral valve interventions-Emphasis on skills development and institutional risk performance

This viewpoint report describes how the evolution of transcatheter mitral valve intervention (TMVI) is influenced by lessons learned from three evolutionary tracks: (1) the development of treatment from mitral valve surgery (MVS) to transcutaneous procedures; (2) the evolution of biomedical engineering for research and development resulting in predictable and safe clinical use; (3) the adaptation to local conditions, impact of transcatheter aortic valve replacement (TAVR) experience and creation of infrastructure for skills development and risk management. Thanks to developments in computer science and biostatistics, an increasing number of reports regarding clinical safety and effectiveness is generated. A full toolbox of techniques, devices and support technology is now available, especially in surgery. There is no doubt that the injury associated with a minimally invasive access reduces perioperative risks, but it may affect the effectiveness of the treatment due to incomplete correction. Based on literature, solutions and performance standards are formulated with an emphasis in technology and positive outcome. Despite references to Heart Team decision making, boundary conditions such as hospital infrastructure, caseload, skills training and perioperative risk management remain underexposed. The role of Biomedical Engineering is exclusively defined by the Research and Development (R&D) cycle including the impact of human factor engineering (HFE). Feasibility studies generate estimations of strengths and safety limitations. Usability testing reveals user friendliness and safety margins of clinical use. Apart from a certification requirement, this information should have an impact on the definition of necessary skills levels and consequent required training. Physicians Preference Testing (PPT) and use of a biosimulator are recommended. The example of the interaction between two Amsterdam heart centers describes the evolution of a professional ecosystem that can facilitate innovation. Adaptation to local conditions in terms of infrastructure, referrals and reimbursement, appears essential for the evolution of a complete mitral valve disease management program. Efficacy of institutional risk management performance (IRMP) and sufficient team skills should be embedded in an appropriate infrastructure that enables scale and offers complete and safe solutions for mitral valve disease. The longstanding evolution of mitral valve therapies is the result of working devices embedded in an ecosystem focused on developing skills and effective risk management actions.

Role of the mitral valve in left ventricular assist device pathophysiology

Functional mitral regurgitation (MR) in the setting of heart failure results from progressive dilatation of the left ventricle (LV) and mitral annulus. This leads to leaflet tethering with posterior displacement. Contrary to common assumptions, MR often does not resolve with LVAD decompression of the LV alone. The negative impact of significant (moderate-severe) mitral regurgitation in the LVAD setting is becoming better recognized in terms of its harmful effect on right heart function, pulmonary vascular resistance and hospital readmissions. However, controversies remain regarding the threshold for intervention and management. At present, there are no consensus indications for the repair of significant mitral regurgitation at the time of LVAD implantation due to the conflicting data regarding potential adverse effects of MR on clinical outcomes. In this review, we summarize the current understanding of MR pathophysiology in patients supported with LVAD and potential future management strategies.

[Perioperative strokes in cardiac surgery]

The frequency of perioperative stroke in cardiosurgical practice may reach up to 10%. The risk of stroke is especially high after coronary artery bypass surgery and valve replacement. Perioperative stroke is related to embolism with the fragments of atherosclerotic plaque, arterial hypotension, cardiac arrhythmias, hypercoagulation, etc. The likelihood of stroke can be reduced by preoperative assessment of the patient. It is important to control blood pressure and saturation during the surgery. The manipulation on aorta should be minimized in order to reduce the risk of perioperative stroke. Important role belongs to timely identification of those who developed stroke after surgery. The only possible method of reperfusion therapy in perioperative stroke is mechanical thrombectomy.

Cerebral atherosclerosis and early ischemic stroke after left-sided valve replacement surgery

OBJECTIVE

Studies have rarely investigated whether cerebral atherosclerosis increases the risk of stroke after valve replacement surgery. This study evaluated the influence of cerebral atherosclerosis on the risk of stroke after left-sided valve replacement surgery.

METHODS

Between 2005 and 2015, preoperative magnetic resonance angiography was performed for 2085 patients who underwent left-sided valve replacement surgery in a tertiary single center to assess intracranial and extracranial cerebral atherosclerosis. The severity was retrospectively assessed on the basis of the atherosclerosis score, determined by the number of steno-occlusions of the cerebral arteries and the degree of atherosclerosis. Associations between cerebral atherosclerosis and postoperative stroke (within 30 days) were evaluated; the overall influence of total cerebral atherosclerosis, and the individual effects of intracranial and extracranial cerebral atherosclerosis on the risk of postoperative stroke were assessed using multivariable models.

RESULTS

Preoperative cerebral atherosclerosis was identified in 626 (30.0%) patients, whereas intracranial cerebral atherosclerosis and extracranial cerebral atherosclerosis were identified in 367 (17.1%) and 412 (19.8%) patients, respectively. Stroke occurred in 54 (2.6%) patients, and the total cerebral atherosclerosis score was independently associated with an increased risk of stroke (odds ratio, 1.23; 95% confidence interval, 1.06-1.44). The intracranial cerebral atherosclerosis scores (odds ratio, 1.44; 95% confidence interval, 1.16-1.78), but not the extracranial cerebral atherosclerosis scores, independently predicted the incidence of stroke.

CONCLUSIONS

Intracranial cerebral atherosclerosis was an important predictor of postoperative stroke, suggesting the necessity of further studies on the feasibility of preoperative screening for cerebral atherosclerosis in patients undergoing left-sided valve replacement surgery.

Perioperative Stroke

PURPOSE OF REVIEW

This review overviews perioperative stroke as it pertains to specific surgical procedures.

RECENT FINDINGS

As awareness of perioperative stroke increases, so does the opportunity to potentially improve outcomes for these patients by early stroke recognition and intervention. Perioperative stroke is defined to be any stroke that occurs within 30 days of the initial surgical procedure. The incidence of perioperative stroke varies and is dependent on the specific type of surgery performed. This chapter overviews the risks, mechanisms, and acute evaluation and management of perioperative stroke in four surgical populations: cardiac surgery, carotid endarterectomy, neurosurgery, and non-cardiac/non-carotid/non-neurological surgeries.

Prevalence of Carotid Stenosis and Incidence of Ischemic Stroke in Patients Undergoing Non-Coronary Cardiac Surgery

Introduction

Many publications on coronary surgery and carotid stenosis (CS) can be found, but we do not have enough information about the relationship between ischemic stroke, CS and non-coronary cardiac surgery.

Objectives

To evaluate the incidence and risk factors associated with the stroke and CS ≥50% in patients undergoing non-coronary surgeries.

Objectives

We assessed 241 patients, aged 40 years or older, between 2009 and 2016, operated in Santa Casa de Misericórdia de Ponta Grossa-PR, Brazil. We perform carotid Doppler in patients 40 years of age or older before any cardiac surgery as a routine. The incidence and possible risk factors for CS ≥50% and perioperative stroke were analyzed by univariate statistical analysis.

Results

11 patients (4.56%) presented perioperative stroke. The risk factor for stroke was CS ≥50%: OR=5.3750 (1.2909-22.3805), P=0.0208. Eighteen patients (7.46%) had CS ≥50% and their risk factors were extracardiac arteriopathy: OR=18.6607 (6.3644-54.7143), P<0.0001; COPD: OR=3.9040 (1.4491-10.5179), P=0.0071; diabetes mellitus: OR=2.9844 (1.0453-8.5204), P=0.0411; recent myocardial infarction: OR=13.8125 (1.8239-104.6052), P=0.0110; EuroSCORE II higher P=0.0056.

Conclusion

The incidences of stroke and CS ≥50% were 4.56% and 7.46%, respectively. The risk factor for stroke was CS ≥50% and for CS ≥50% were extracardiac arteriopathy, COPD, diabetes mellitus, recent myocardial infarction and higher EuroSCORE II.

Risk and Outcome after Simultaneous Carotid Surgery and Cardiac Surgery: Single Centre Experience

OBJECTIVE

Carotid artery stenosis in patients undergoing open-heart surgery may increase risk and deteriorate outcome. The aim of the study was the analysis of risks and outcome after simultaneous carotid and cardiac surgery.

METHODS

We retrospectively reviewed the medical records of 100 consecutive patients who underwent simultaneous carotid surgery and open-heart surgery during a 5-year period (from 2006 to 2010). Seventy patients were male and 30 female; the mean age was 70.9±7.9 years (median: 71.8 years). Seventy-three patients underwent coronary bypass grafting (CABG), 18 patients combined CABG and valve procedures, 7 patients CABG combined with other procedures, and 3 patients isolated valve surgery. More than half of patients had had bilateral carotid artery pathology (n=51) including contralateral carotid artery occlusion in 12 cases.

RESULTS

Carotid artery patch plasty was performed in 71 patients and eversion technique in 29. In 75 cases an intraluminal shunt was used. Thirty-day mortality rate was 7% due to cardiac complications (n=5), metabolic disturbance (n=1), and diffuse cerebral embolism (n=1). There were no carotid surgery-related deaths. Postoperatively, transient cerebral ischemia occurred in one patient and stroke with mild permanent neurological deficit (Rankin level 2) in another patient.

CONCLUSION

Simultaneous carotid artery surgery and open-heart surgery have low risk. The underlying cardiac disease influences outcome.

Perioperative stroke: pathophysiology and management

Although perioperative stroke is uncommon during low-risk non-vascular surgery, if it occurs, it can negatively impact recovery from the surgery and functional outcome. Based on the Society for Neuroscience in Anesthesiology and Critical Care Consensus Statement, perioperative stroke includes intraoperative stroke, as well as postoperative stroke developing within 30 days after surgery. Factors related to perioperative stroke include age, sex, a history of stroke or transient ischemic attack, cardiac surgery (aortic surgery, mitral valve surgery, or coronary artery bypass graft surgery), and neurosurgery (external carotid-internal carotid bypass surgery, carotid endarterectomy, or aneurysm clipping). Concomitant carotid and cardiac surgery may further increase the risk of perioperative stroke. Preventive strategies should be individualized based on patient factors, including cerebrovascular reserve capacity and the time interval since the previous stroke.