Heart Valve Clinic: A Model for Treatment of Structural Heart Disease

Background and Aim of the Study: Valvular heart disease (VHD) should be managed by a Heart Valve Team (HVT) for optimal treatment. Although the prevalence of VHD is increasing, an overall lack of universal implementation of the HVT continues to exist. Here we present our model of care within a Veteran’s Affairs Medical Center (VAMC). Materials and Methods: All patients referred to our VAMC with structural valvular disease have been managed within our multidisciplinary heart valve clinic since 2006. The heart valve clinic consists of a dedicated valve surgeon as well as both a dedicated noninvasive imaging cardiologist and cardiac MRI/CT cardiologist. Cases are reviewed on a weekly basis with multidisciplinary input to guide treatment strategy. Therapy includes medical management, facilitation of further diagnostic workup, and referral for operative intervention. Results: Between 2006 and 2015, 560 patients have been evaluated in HVC. Overall, new patient yearly volume has nearly tripled with now over 90 new consults seen yearly. Of the patients evaluated, 313 were referred for operative intervention with follow up post-operatively to affirm adequate post-procedural function. Following HVC referral trends, operative yearly volume has increased 33% over the last year years compared to the first three years of the program. The heart valve clinic has also matured to support a dedicated TAVR program. Conclusions: As the options for heart valve therapy and indications for surgery continue to evolve, a multidisciplinary team to guide decision making is imperative. We present the success and growth of our heart valve clinic within a VAMC as a structural model that can be translated into both the community and academic setting.


Introduction
Structural valvular heart disease (VHD) should be treated by an integrated team of medical and surgical subspecialties.The need for coordination has become increasingly important with the advent of transcatheter valve placement (TVR) allowing otherwise prohibitive surgical candidates the opportunity for valve replacement.Though defined guidelines for operative intervention exist, the timing, strategy, and suitability of intervention must be individualized for each patient as referral for operative intervention has become a complex algorithm of decision making involving various imaging modalities, longitudinal patient care, and optimization of medical therapy.
The American College of Cardiology and American Heart Association Task Force in addition to the European Society of Cardiology (ESC) and the European Association for Cardio-Thoracic Surgery (EACTS) guidelines suggest the concept of a Heart Valve Team (HVT) for optimal management of patents with VHD [1] [2].Ideally, the HVT manages VHD from presentation to prevent the often silent clinical progression to irreversible disease.With continual consideration of both medical and surgical factors, VHD patients can undergo appropriate intervention when surgery carries lower risk and is more effective in improving survival outcomes [3].
With the ongoing expansion of TVR options and new technology, the use of a HVT to guide therapy is highlighted in a statement from the Society of Thoracic Surgeons (STS) [4].The heart valvecenter is described as the ideal venue for TVR expansion to serve as "guardrails" in the face of new technology.Pre-procedure evaluation by a multidisciplinary team conference, valvular heart disease clinics, and joint performance of the procedure and post-operative care are discussed as essential elements of a successful TVR team.
Though the recommendations to implement multidisciplinary care and follow up to guide management of VHD are clear, little has been described in the literature regarding the structure and implementation of the Heart Valve Clinic (HVC).As a VA referral center for the surgical treatment of valve disease, our center has been afforded the opportunity to centralize care of VHD within a specialized HVT.As a diverse, complex, and rigorously tracked and monitored population, the VA health system presents an optimal setting for implementation of the HVC.Herein, we discuss the structure, success, and growth of our HVC within a Veteran's Affairs Medical Center (VAMC) at a regional referral center as a model for the treatment of valvular heart disease in the era of TVR therapy.

Goals of the Heart Valve Clinic
The overarching goal of the HVC at our institution is to provide multidisciplinary, timely management of VHD.Our designation as a Veteran's Affairs Hospital regional referral center allows for centralized care with excellent continuity to help prevent the potential serious consequences of VHD patients "lost to follow up."This goal is facilitated in four phases 1) Proactive, preemptive identification of patients with moderate to severe valvular disease 2) Initial assessment 3) Interim assessment, and 4) Long term follow-up (Table 1).
Upon referral, initial objectives include a complete medical assessment delineating of the extent and severity of the structural valvular disease.The need for initial imaging (discussed in detail later) is facilitated in addition to management of heart failure and blood pressure medications.Interim assessment goals which are facilitated in follow up clinic visits and Heart Valve Conference include discussion regarding appropriate surgical referral, patient education, and follow up imaging and referral for additional medical resources as needed for medical optimization.Long term objectives include optimization of surgical intervention in those patients who are followed in our HVC as well as a decrease in the overall VHD health care related costs from hospital admissions and delayed care.

Patient Selection
As a tertiary referral center for cardiac surgery in a wide geographic region, the referral base is diverse and presents from multiple venues.Patients appropriate for referral include those with moderate to severe valvular dysfunction that may benefit from intervention, adult congenital heart disease, aortic pathology, bicuspid aortic valves in the context of connective tissue disorder, and those with structural pathologies (i.e.ASD, PFO, and VSD).Cases of mild valvular disease are not referred for further assessment in our clinic however communication is made with the referring physician to ensure appropriate interval echocardiographic follow up to detect disease progression.

Referral, Initial Workup, and Follow-Up
As the regional heart valve clinic for the area, the first notable set of referrals is initiated outside our institution.After reviewing patient records from the referring institution to affirm the appropriateness of the referral, patients are seen for In addition to outside institution referrals, patients are referred from within our hospital from primary care clinics, within cardiology, by the cardiothoracic team, and also by our those cardiologists who specialize in ECHO (Figure 1).If patients are found to have VHD, an inquiry is made back to the referring provider to recommend referral to our HVC.
Figure 1.Structure of referral base to HVC and subsequent follow up.

Imaging Modalities
The

Growth and Expansion
Our center has been the regional VISN referral cardiac surgery center since Of the 12 TAVRs performed, there were no cases of 30-day mortality, stroke, MI, prosthetic valve endocarditis, or conversion to surgical aortic valve replacement (Table 3(a)).Heart failure class improved at 30 day follow up in all but one patient (Table 3(b)).On follow up analysis which was 100% complete, there were no deaths (mean duration 9.9 ± 4.3 months; range 3 -17 months).Our outcomes highlight the importance of patient selection for TAVR within the context of a multidisciplinary care team with broad expertise and experience.

Discussion
The prevalence of HVD continues to increase with implementation of a Heart    specialized expertise in imaging, clinical assessment, and surgery for patients with VHD [8].Chambers asserts that this structured, training program overseen by national and international professional societies could affect improvement in surgical outcomes, particularly with mitral valve repair as rates of repair are higher with lower mortality in high volume centers.Lancellotti adds that in addition to Centres of Excellence, the use of national outcomes registries to improve adherence to national guidelines and ensure standards for best practice are essential in this model [9].
Designated referral centers of excellence are particularly important in the TAVR era.As described in our HVC model, the evolution of a TAVR program from HVC is a natural progression.An HVC approach leads to a more directed, time and cost-efficient work-up in the TVR patient as the multidisciplinary team approach ensures safe, appropriate, implementation of advancing therapy [10].
As indications for TAVR include lower risk patients and new centers offer therapy, implementation must continue to take place within a multidisciplinary team to ensure safe and appropriate application [11].
The first VA to publish TAVR results in 2013 established the safety and excellent outcomes of TAVR within a VAMC [12].Our early outcomes echo their success in providing the Veteran population a much needed alternative to surgical AVR in the high risk patient.In the future, the structure of the VA system presents an opportunity for Veteran care models in particular the HVC to play a critical role in VHD treatment.As described by Kelly and Mudy, the VAMC TAVR experience is critical to understanding the future of this new technology [13].Given the innate centralized care, database enrollment, and long-term follow up abilities, the VA is an ideal frontier for TAVR within an active and productive HVC.

Conclusion
As the options for heart valve therapy and indications for surgery continue to evolve, a multidisciplinary team to guide decision making is imperative.We present the success and growth of our heart valve clinic within a VAMC as a structural model that can be translated into both the community and academic setting.

2001.
Institution of our HVC began in 2006 with the coordination of a dedicated cardiothoracic surgeon and cardiologist.Since that time, the program has grown to support four cardiology and cardiothoracic physician assistants, an advanced cardiac imaging cardiologist, structural interventional cardiology attending, cardiology fellow, CT research fellow, database administrator, and nurse coordinator in conjunction with our transcatheter aortic valve replacement (TAVR) program (Figure 2).Since 2006, 560 patients have been evaluated in HVC.Overall, new patient yearly volume has nearlytripled with now over 90 new consults seen yearly.Of the patients evaluated, 313 were referred for operative intervention with follow up post-operatively to affirm adequate post-procedural function.Following HVC referral trends, operative yearly volume has increased 33% over the last three years compared to the first three years of the program (Figure 3).The heart valve clinic has also matured to support a dedicated TAVR program.

Figure 3 .
Figure 3. Increase in patients evaluated in valve clinic and operative volume over time.

Table 1 .
Objectives of the HVC.initial assessment.Echocardiography (ECHO) is performed in house to obtain a real-time, baseline assessment of structure and function.These initial visits are coordinated within our HVT which consists of physician extenders, dedicated echocardiography nurses, and cardiologists with early involvement of car- *Includes dedicated diabetes clinic, blood pressure control medications (B-blocker, ACE or ARB as indicated), aspirin or dual-antiplatelet therapy use as indicated, smoking cessation counseling, and cardiopulmonary rehab as indicated.anPost-operatively, patients are followed in the cardiothoracic clinic and heart valve clinic with repeat ECHO.If post-operative ECHO is without structural concerns, patients are then transitioned back to their local primary care doctor for ongoing surveillance and management of medical care.For patients who do not meet criteria for operative intervention, appropriate follow up is initiated at 1 month, 3 months, 6 months or a year according to guidelines based on severity of disease.Follow up is managed by a nurse coordinator to ensure return to clinic appointments and feedback to referring physicians.Any patients with clinical uncertainties or borderline criteria for operative intervention are presented periodically in heart valve conference to follow changes and reassess the need for operative intervention.

Table 2 .
cornerstone of management of VHD is cardiac imaging.As such, our HVC and conference include a dedicated noninvasive imaging team, cardiac MRI/CT cardiologist, and dedicated valve surgeon.During Heart Valve Conference, all Detailed description of the utilization of various imaging modalities in aortic and mitral valvular disease within our HVC.

Table 3 .
Clinical Outcomes of early TAVR Experience of program evolving from long standing valve clinic.