Perioperative Complications in Infective Endocarditis

Infective endocarditis is a challenging condition to manage, requiring collaboration among various medical professionals. Interdisciplinary teamwork within endocarditis teams is essential. About half of the patients diagnosed with the disease will ultimately have to undergo cardiac surgery. As a result, it is vital for all healthcare providers involved in the perioperative period to have a comprehensive understanding of the unique features of infective endocarditis, including clinical presentation, echocardiographic signs, coagulopathy, bleeding control, and treatment of possible organ dysfunction. This narrative review provides a summary of the current knowledge on the incidence of complications and their management in the perioperative period in patients with infective endocarditis.

Anesthesia Considerations in Infective Endocarditis

The management of infective endocarditis is complex and inherently requires multidisciplinary cooperation. About half of all patients diagnosed with infective endocarditis will meet the criteria to undergo cardiac surgery, which regularly takes place in urgent or emergency settings. The pathophysiology and clinical presentation of infective endocarditis make it a unique disorder within cardiac surgery that warrants a thorough understanding of specific characteristics in the perioperative period. This includes, among others, echocardiography, coagulation, bleeding management, or treatment of organ dysfunction. In this narrative review article, the authors summarize the current knowledge on infective endocarditis relevant for the clinical anesthesiologist in perioperative management of respective patients. Furthermore, the authors advocate for the anesthesiologist to become a structural member of the endocarditis team.

Does patent foramen ovale presence procure favourable outcomes in patients with severe rheumatic mitral stenosis?

Mitral stenosis (MS) is tolerated for an extended period in patients with atrial septal defect (ASD) known as Lutembacher syndrome due to depressurizing effect. In a similar way, patients with patent foramen ovale (PFO) may have clinical benefits in severe MS. We aim to evaluate the clinical effects of PFO in rheumatic MS. Transthoracic and transesophageal echocardiography records of the patients with symptomatic severe MS were screened for the period between 2008 and 2019 in a single center. 320 symptomatic patients with severe MS were included and presence of PFO recorded. Left atrial appendix (LAA) thrombotic status was defined as clear, spontaneous echo contrast, and thrombus. Two different statistical models were used to determine the predictors of either smallest (mitral valve area) MVA at symptomatic presentation or more thrombogenic LAA. 34 patients had PFO. Multivariable ordinary least square model demonstrated that increase in systolic pulmonary arterial pressure, ejection fraction and presence of PFO were associated with smaller MVA on presentation. Multivariable proportional odds logistic regression model demonstrated that advanced age, increased left atrial diameter, absence of PFO were associated with more thrombotic status whereas larger MVA was associated with decreased thrombotic status in LAA. Presence of PFO in severe MS results in two clinical benefits as (i) being asymptomatic with smaller MVA and (ii) having less LAA thrombosis probably caused by depressurizing effect on the left atrial pressure. Our study could serve as an example for patient groups with expected symptomatic benefits from left atrium pressure offloading interventions.

The 2020 ACC/AHA Guidelines for Management of Patients With Valvular Heart Disease: Highlights and Perioperative Implications

Valvular heart disease contributes to a large burden of morbidity and mortality in the United States. During the last decade there has been a paradigm shift in the management of valve disease, primarily driven by the emergence of novel transcatheter technologies. In this article, the latest update of the American College of Cardiology/American Heart Association valve heart disease guidelines is reviewed.

Safety of Noncardiac Surgery in Patients With Hypertrophic Obstructive Cardiomyopathy at a Tertiary Care Center

OBJECTIVES

This study's purpose was to review non-cardiac surgery (NCS) in patients with hypertrophic obstructive cardiomyopathy (HOCM) to examine perioperative management and quantify postoperative mortality and worsening heart failure.

DESIGN

Retrospective review.

SETTING

A single tertiary care center.

PARTICIPANTS

The study included 57 adult patients with HOCM who underwent NCS from January 1, 1996, through January 31, 2014.

INTERVENTIONS

Noncardiac surgery.

MEASUREMENTS AND MAIN RESULTS

The authors identified 57 HOCM patients who underwent 96 NCS procedures. Vasoactive medications were administered to the majority of NCS patients. Three patients (3%) died within 30 days of NCS, but causes of death did not appear to be cardiac in nature. Death after NCS was not significantly associated with preoperative left ventricular ejection fraction (p = 0.2727) or peak instantaneous systolic resting gradient (0.8828), but was associated with emergency surgery (p = 0.0002). Three patients experienced worsening heart failure postoperatively, and this was significantly associated with preoperative New York Heart Association Class III-IV symptoms compared with I-II symptoms (p = 0.0008).

CONCLUSIONS

HOCM patients safely can undergo NCS at multidisciplinary centers experienced in caring for these patients. The mortality rate in this study was less than that reported in the majority of other studies. Postoperative complications, including increasing heart failure, may occur, especially in patients with more severe preoperative cardiac symptoms.

Anesthetic management of a patient with obstructive prosthetic aortic valve dysfunction: a case report

We present a 55-year-old female patient who underwent burr-hole drainage due to chronic subdural hematoma, with obstructive prosthetic aortic valve dysfunction. Anesthetic management of a patient with severe obstructive prosthetic aortic valve dysfunction can be challenging. Similar considerations should be given to patients with aortic stenosis with an additional emphasis on thrombotic complication due to discontinuation of anticoagulation, which may further jeopardize the valve dysfunction. This case emphasizes the importance of a comprehensive understanding of the etiology and hemodynamic consequences of obstructive prosthetic valve dysfunction and the adequacy of anticoagulation for patients undergoing noncardiac surgery even after a successful valve replacement.

Morbid obesity: obscuring the diagnosis of aortic stenosis in a patient with cardiogenic wheezing

We report the case of a morbidly obese 65-year-old female who presented with repeated hypotensive episodes following dialysis. She was misdiagnosed as suffering from asthma, and eventually was found to have severe aortic stenosis. Obesity has become a common and formidable obstacle to gathering important diagnostic information in patients. Modern diagnostic lab tests and imaging modalities such as transthoracic echocardiography (TTE) can provide spurious data in the morbidly obese population, which can ultimately lead to misdiagnosis. In this clinical vignette, we discuss the relationship between the basic pathophysiologic mechanisms underlying aortic stenosis and patient clinical presentation. We also review the relevant literature and discuss the impact of obesity on the diagnosis of this condition.

[Transcutaneous aortic valve implantation: Anesthetic and perioperative management]

OBJECTIVE

To describe the perioperative management, from the point of view of the anesthesia-intensive care unit specialist, of patients with aortic stenosis who undergo transcatheter aortic valve implantation (femoral or apical TAVI).

DATA SOURCE

The PubMed database (http://www.ncbi.nlm.nih.gov/entrez/query.fcgi) was queried, using the following keywords: aortic stenosis, transcatheter aortic valve implantation TAVI, outcome, complications, anesthesia.

DATA SYNTHESIS

TAVI is performed in patients suffering from aortic stenosis and presenting with numerous comorbidities, high-predicted perioperative mortality and/or contraindications to conventional cardiac surgery. TAVI is performed either by percutaneous transfemoral or transapical puncture of the left ventricle (LV) apex. These patients are older, have more comorbidities than those undergoing aortic valve replacement surgery and perioperative mortality predicted by risk scores is higher. While transapical TAVI is performed with general anaesthesia, transfemoral TAVI can be performed with either general or locoregional anaesthesia and/or sedation. The choice of the anaesthetic technique for transfemoral TAVI depends on the patient's medical history, the technique chosen for valve implantation, the type of monitoring and the anticipated hemodynamic problems. The incidence of complications following TAVI is high, some are common to surgical aortic valve replacement, and others are specific to this technique. Because of the prevalence of comorbidities, the hemodynamic-specific constraints of this technique and the incidence of complications, anaesthetic and perioperative management (evaluation, anaesthetic technique, monitoring, post-surgery care) requires the same level of expertise as in cardiac surgery anaesthesia.

CONCLUSION

TAVI expands treatment options for patients with aortic valve stenosis. The anaesthesia team must be involved in the care of these patients with the same level of expertise and care as in heart surgery on critical patients.

Anesthetic considerations for patients with advanced valvular heart disease undergoing noncardiac surgery

Patients with valvular heart disease represent a growing segment of the population and can present major challenges to clinical anesthesiologists. This review focuses on patients with advanced left-sided valvular disease undergoing noncardiac surgery. The pathophysiology and anesthetic implications of aortic stenosis and insufficiency and mitral stenosis and insufficiency are discussed, with a focus on optimizing perioperative management and decision making for patients with these conditions.

Effect of electrical stimulus parameters on the development and propagation of action potentials in short excitable fibres

Intracellular action potentials (IAPs) produced by short fibres in response to their electrical stimulation were analysed. IAPs were calculated on the basis of the Hodgkin-Huxley (1952) model by the method described by Joyner et al. (1978). Principal differences were found in processes of activation of short (semilength L less than 5 lambda) and long fibres under near-threshold stimulation. The shorter the fibre, the lower was the threshold value (Ithr). Dependence of the latency on the stimulus strength (Ist) was substantially non-linear and was affected by the fibre length. Both fibre length and stimulus strength influenced the IAP amplitude, the instantaneous propagation velocity (IPV) and the site of the first origin of the IAP (and, consequently, excitability of the short fibre membrane). With L less than or equal to 2 lambda and Ithr less than or equal to Ist less than or equal to 1.1Ithr, IPV could reach either very high values (so that all the fibre membrane fired practically simultaneously) or even negative values. The latter corresponded to the first origin of the propagated IAP, not at the site of stimulation but at the fibre termination or at a midpoint. The characters of all the above dependencies were unchanged irrespective of the manner of approaching threshold (variation of stimulus duration or its strength). Reasons for differences in processes of activation of short and long fibres are discussed in terms of electrical load and latency. Applications of the results to explain an increased jitter, velocity recovery function and velocity-diameter relationship are also discussed.