Heart Valve Disease: A Guide to Patient Management After Surgery
Eric G. Butchart, Christa Gohlke-Barwolf, Manuel J. Antunes, Roger J.C. Hall, eds
199 pages. Abingdon, Oxon, UK: Informa Healthcare; 2006. $75.00. 1–84214–308–7
The long-term comprehensive care of patients after heart valve surgery is not the purview of any single practitioner. Patterns of care vary both within and between countries. Caregivers may include the patient, family, primary care physician, general cardiologist, noninvasive imaging specialist, heart failure specialist, electrophysiologist, cardiac surgeon, advanced practice nurse, physician’s assistant, pharmacist, and exercise therapist. Individual focus on narrowly defined aspects of care allows opportunity for redundancy and inefficiency, as well as for uncertain lines of responsibility when clinical change mandates prompt action. The relative infrequency with which complex postoperative problems are seen by most care providers, the lack of a formal educational curriculum that deals with their recognition and management, and the rapidly changing fields of heart valve surgery and percutaneous intervention add to these challenges.
In an attempt to close some of our gaps in knowledge and familiarity, the editors of Heart Valve Disease: A Guide to Patient Management After Surgery, have assembled a team of European and American experts to produce a text of broad scope and solid depth. By design, the book does not include a discussion of management after balloon valvuloplasty, though brief mention is made of anticoagulation strategies in patients with mitral stenosis and significant left atrial spontaneous echo contrast who must undergo trans-septal puncture as part of this procedure.
The book begins with a discussion of postoperative intensive care, the elements of which are not restricted to patients who undergo isolated valve surgery. The use of flow diagrams both here and in several other chapters is particularly helpful. There is no discussion of the indications for permanent pacemaker therapy, an issue that arises not infrequently in the care of elderly patients early after aortic valve replacement for aortic stenosis, in whom there may be extensive calcification of the valve apparatus and risk of high-grade atrioventricular block. The discussion about atrial fibrillation is important, though the attention paid to the patient with preexcitation would seem unnecessary in this context. The text does not address the treatment of early postoperative arrhythmias in patients with mitral valve disease who have undergone either transcatheter ablation and/or surgical maze with left atrial appendage ligation. Mention is not made of the challenges posed by the patient with coronary artery disease for whom percutaneous coronary intervention and stenting have been performed immediately prior to minimally invasive valve surgery as part of a “hybrid” approach to their treatment. Management of perioperative antiplatelet and anticoagulant therapy for these patients varies considerably. Inclusion of a section on predischarge planning and the postoperative timing of noninvasive follow-up (ie, pre- or postdischarge) would have been useful. The subsequent chapter on cardiac rehabilitation is a helpful reminder of the benefit of this intervention for patients after cardiac surgery, even for those without coronary artery disease. Relatively little attention is paid to the physical examination findings in Chapter 3 on postdischarge follow-up. An important illustration of normal and abnormal prosthetic valve sounds appears much later, in Chapter 10. Clinicians are often confused and uncertain about the range of postoperative physical examination, electrocardiographic, and chest x-ray findings, which might be considered allowable in this patient cohort. The discussion of echocardiography here is overshadowed by the more authoritative chapters that follow.
Chapters 4 and 5 (Echocardiographic Follow-Up, Normal Echocardiographic Data of Prosthetic Valves) comprise an excellent summary of the use of this imaging modality for the evaluation of patients after heart valve surgery. The images provided are excellent, the tables are well referenced, and the text is clear and concise. An illustrative example of a cine-fluoroscopic examination in a patient with suspected prosthetic valve thrombosis is also included. Indications for use of the emerging technologies of cardiac computed tomography and magnetic resonance for the assessment of patients after heart valve surgery are not addressed, though it is recognized that echocardiography and cardiac catheterization remain the mainstays of evaluation.
At this juncture, reorganization of the book’s chapters might have improved the content flow. Specifically, the last chapter (Chapter 19), which is devoted to the evolution and current state of reporting of prosthetic valve-related complications, would seem appropriate for inclusion here, and not at the end of the book. Expansion of the section on structural valve degeneration (for both mechanical and xenograft prostheses) and inclusion of a discussion on the durability of allo- and autografts would have been a helpful segue into the next chapter (Chapter 6), which is devoted to problems related to homografts, autografts, and stentless valves. The black and white illustrations in this latter chapter, taken from another publication, suffer when compared to the intraoperative color photographs provided in the subsequent discussion (Chapter 7) that deals with valve repair. No information is provided on the long-term outcomes of valve-sparing aortic root reconstruction with either the remodeling or re-implantation technique, nor to surgical decision-making in the primary management of tricuspid regurgitation at the time of initial mitral valve repair. Residual tricuspid regurgitation is common after repair and a frequent source of some confusion to the nonsurgeon.
Chapters 8 to 10 deal with antithrombotic therapy, thromboembolism, and prosthetic valve thrombosis, respectively. Chapter 8, in which Butchart et al discuss antithrombotic management, is particularly thoughtful, comprehensive, and concise. The authors emphasize their points of differences with current ACC/AHA (2006 Update) and ACCP (2004, with Update anticipated in 2008) guideline recommendations and provide alternative suggestions for these challenging issues. The significant content overlap between the next 2 chapters (Chapters 9 and 10) would have allowed a single discussion, augmented by the illustrations, tables, and flow diagrams already provided. Chapter 11, which deals with valve-related hemolysis, is a succinct review of this infrequent though important complication.
The prevention, assessment, and treatment of prosthetic valve endocarditis are the subjects of the next 2 chapters (Chapters 12 and 13). References are not provided in the footnotes for the tables that list recommended antibiotic regimens. Pre-2006 multicenter registry data from the International Collaboration on Endocarditis specific to prosthetic valve endocarditis are not cited.
The management of the pregnant woman who has undergone previous heart valve surgery is particularly treacherous and the chapter (Chapter 14) devoted to this subject is a well-written brief summary of the major issues that confront the patient, fetus, and care provider. Because the subsequent 2 chapters (Chapters 15 and 16) focus predominantly on the complex management of antithrombotic therapy during pregnancy and noncardiac surgery, respectively, it would have been thematically consistent to group them with the previous chapters devoted to related topics (Chapters 8 to 10). The section on recommendations for antithrombin therapy during pregnancy in women with mechanical heart valves provides clear and concise guidelines for the practitioner, though the quoted use of warfarin is at odds with standard practice patterns in the US. The authors correctly point out the relative lack of data for low molecular weight heparins, despite their increased use.
The inclusion of a chapter (Chapter 17) on rheumatic fever prophylaxis serves as a useful reminder of the need to continue secondary prevention measures after heart valve surgery in at-risk patients. Finally, the chapter (Chapter 18) on follow-up and management of children draws important distinctions between this population and adults.
In summary, Heart Valve Disease: A Guide to Patient Management After Surgery is an important attempt to address several aspects of surveillance and clinical care after heart valve surgery. As noted, there are a few content gaps. Although the book’s organization is inconsistent in places, the text and illustrations in several of the chapters, particularly those that deal with echocardiography and antithrombotic therapy, are excellent. The reader is encouraged to cross-reference management recommendations with those authored by ACC/AHA, ACCP, and ESC. Continued advances in heart valve surgery, prosthesis design and durability, the “hybrid” approach to patients with concomitant coronary artery disease, the combined use of operative and/or transcatheter treatments for arrhythmias, the anticipated availability of oral antithrombin inhibitors, and the changing landscape of patient preferences for tissue versus mechanical prostheses will steadily influence the approach to long-term follow-up. Continuing professional education is a critical component of quality care. The curriculum provided herein is a good first step to highlight an oft-neglected aspect of training.