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Characteristics and Outcomes of Patients With Severe Aortic Stenosis Discussed by the Multidisciplinary “Heart Team” According to Treatment Allocation
HLC 2862 No. of Pages 6
Heart, Lung and Circulation (2019) xx, 1–6 1443-9506/04/$36.00 https://doi.org/10.1016/j.hlc.2019.02.192
ORIGINAL ARTICLE
Characteristics and Outcomes of Patients With Severe Aortic Stenosis Discussed by the Multidisciplinary ‘‘Heart Team” According to Treatment Allocation Conor W. Rea, MBChB, Tom Kai Ming Wang, FRACP, Peter N. Ruygrok, MD, FRACP *, Karishma Sidhu, MSc, Tharumenthiran Ramanathan, PhD, FRACS, Parma Nand, FRACS, James T. Stewart, MD, FRACP, Mark W.I. Webster, FRACP Green Lane Cardiovascular Service, Auckland City Hospital, Auckland, New Zealand Received 20 February 2018; received in revised form 30 October 2018; accepted 26 February 2019; online published-ahead-of-print xxx
Background
Transcatheter aortic valve implantation (TAVI) is an alternative and effective contemporary intervention to surgical aortic valve replacement (SAVR) for patients with severe aortic valve disease at increased surgical risk. Guidelines recommend a multidisciplinary ‘‘Heart Team” (MHT) review of patients considered for a TAVI procedure, but this has been little studied. We reviewed the characteristics, treatments and outcomes of such patients reviewed by the MHT at our centre.
Methods
Data on consecutive patients with severe aortic valve stenosis discussed by the Auckland City Hospital MHT from June 2011 to August 2016 were obtained from clinical records. Patient characteristics, treatment and outcomes were analysed using standard statistical methods.
Results
Over the 5-year period 243 patients (mean age 80.2 8.0 years, 60% male) were presented at the MHT meeting. TAVI was recommended for 200, SAVR for 26 and medical therapy for 17 patients, with no significant difference in mean age (80.2 8.3, 80.4 6.1, 80.4 7.3 years, respectively) or EuroSCORE II (6.5 4.7%, 5.3 3.6%, 6.7 4.3%, respectively). Over time, there was an increase in the number of patients discussed and treated, with no change in their mean age, but the mean EuroSCORE II significantly decreased (TAVI p = 0.026, SAVR p = 0.004). Survival after TAVI and SAVR was similar to that of the age-matched general population, but superior to medical therapy p = 0.002 (93% (n = 162), 84% (n = 21) and 73% (n = 18) at one year and 85% (n = 149), 84% (n = 21) and 54% (n = 13) at 2 years, respectively).
Conclusions
An increasing number of patients were discussed at the MHT meeting with the majority undergoing TAVI, with a similar age and EuroSCORE II to those allocated SAVR or medical therapy. Survival following TAVI and SAVR was superior to medical therapy and similar to the age-matched general population. These findings suggest that the MHT process is robust, consistent and appropriately allocating a limited treatment resource.
Keywords
TAVI Aortic stenosis AVR Heart team Multidisciplinary
*Corresponding author at: Green Lane Cardiovascular Service, Auckland City Hospital, Private Bag 92024, Auckland, 1030, New Zealand, Email: PRuygro [email protected] © 2019 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.
Please cite this article in press as: Rea CW, et al. Characteristics and Outcomes of Patients With Severe Aortic Stenosis Discussed by the Multidisciplinary ‘‘Heart Team” According to Treatment Allocation. Heart, Lung and Circulation (2019), https://doi.org/10.1016/j.hlc.2019.02.192
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Introduction Surgical aortic valve replacement (SAVR) is the gold standard treatment for patients with severe symptomatic aortic valve disease [1,2]. Transcatheter aortic valve implantation (TAVI) has grown significantly over the last decade as an alternative to SAVR. Early randomised trials demonstrated the superiority of TAVI versus medical therapy (MT) in inoperable patients, and comparable to SAVR in high risk patients [3–5]. More recent trials, in intermediate risk patients, have found that transfemoral TAVI with newergeneration valves achieve similar [6], or better outcomes than SAVR [7,8]. Clinical decision-making for selecting the optimal treatment modality is an important rationale for the contemporary concept of the multidisciplinary ‘‘Heart Team” (MHT) [1,9], developed to establish dialogue, consensus and caseby-case recommendation of the most appropriate treatment strategy. It may be composed of cardiologists, cardiothoracic surgeons, anaesthetists, intensivists, radiologists, geriatricians and nurse coordinators, with the intention of obtaining multidisciplinary input and expertise to create and foster robust decision making. Guidelines recommend the implementation of the MHT for managing aortic valve disease, but there remains a paucity of literature describing the characteristics and impact of such a process [1]. TAVI is restricted in the New Zealand public health care system to high-risk but operable patients, and was introduced to Auckland City Hospital in 2011 handin-hand with the MHT discussion process. We reviewed the characteristics, treatment allocation and outcomes of all patients with severe aortic valve disease being considered for TAVI and discussed by the MHT.
Methods This retrospective study reviewed all patients discussed at the MHT meeting since its introduction with TAVI at Auckland City Hospital in April 2011 until August 2016. All patients were first presented at the regional cardiosurgical conference and accepted for SAVR, albeit with high risk, to ensure only operable patients are considered for TAVI. The MHT team consists of the presenting, interventional (at least two) and imaging cardiologists, cardiac surgeons, anaesthetists, cardiovascular intensivists, geriatricians and TAVI nurse co-ordinator, meeting 2-weekly to monthly. The meeting is chaired by an independent cardiologist not involved in TAVI procedures. Clinical baseline and procedural characteristics and outcomes were obtained from clinical records and documented minutes of all MHT meetings, and the EuroSCORE II [10] calculated for all patients. Treatment allocation consisted of TAVI, SAVR or medical therapy. Patient mortality data was obtained from the National Mortality Collection and was complete up to 15 October 2016 and thus was the endpoint for all data collection. The period of follow-up for all patients
was from the time of discussion at the MHT to either the time of their death or data collection from the National Mortality Collection, should that individual still be alive. Mean survival time was the primary outcome of interest. Standard statistical analyses were performed. The Wilcoxon Rank-Sum Test was used to compare quantitative variables and the Fisher’s Exact Test for categorical variables. Kaplan Meier survival curves were constructed according to treatment received. Those patients who lived overseas and, thus, for whom no follow-up was available (n = 11), died whilst awaiting allocated treatment (n = 5) and those still awaiting allocated treatment at the time of analysis (n = 3) were excluded. A log-rank test was performed to compare survival. The projected survival of the general age-matched population in New Zealand was obtained [11]. Statistical analyses were performed using the statistical package SAS version 9.3. All tests were two-sided with p < 0.05 considered statistically significant.
Results There were 243 patients presented at MHT during the study period. The population consisted of patients referred from eight New Zealand District Health Boards (Waitemata 77, Counties Manukau 62, Auckland City 47, Northland 32, Southern 11, other 3) and two overseas countries (Tahiti 10, other 1). Mean age was 80.2 8.0 years and 60% of the cohort was male, with an average EuroSCORE II of 6.4 4.6. Of the 243 patients discussed at the MHT, TAVI was recommended for 200 (82%), SAVR for 26 (11%) and MT for 17 (7%) patients, with no significant difference in mean age (80.2 8.3, 80.4 6.1, 80.4 7.3, respectively) or EuroSCORE II (6.5 4.7, 5.3 3.6, and 6.7 4.3, respectively) between the three groups. Table 1 lists baseline characteristics by treatment allocation cohort. Of the 200 patients assigned to TAVI, three crossed over to the SAVR group, six to the MT group and four died awaiting treatment. Of the 26 patients for SAVR, zero crossed over to TAVI, three to MT and one died awaiting treatment. Of the 17 patients who were assigned to MT, one crossed over to TAVI and zero to SAVR (Figure 1). The mean time from MHT discussion to treatment was 60 days for TAVI patients, 87 days for SAVR patients and 0 days for those allocated to MT as they continued their usual therapy. Of the 188 patients who actually received TAVI, the approach was 147 transfemoral, 24 transaortic and 17 transapical. Figure 2 illustrates the number of patients discussed at MHT and undergoing TAVI per 6month period. Both increased steadily over time. The mean period of follow-up was 2.0 1.4 years. Correlation analyses of the trend in mean EuroSCORE II of both TAVI and SAVR over the 5-year study period showed a significant decrease over time (TAVI p = 0.026, SAVR p = 0.004) but age remained similar (Figure 3). Survival was similar for TAVI and SAVR patients with both being significantly longer than those receiving MT p = 0.002 (93% (n = 162), 84% (n = 21) and 73% (n = 18) at 1 year and 85%
Please cite this article in press as: Rea CW, et al. Characteristics and Outcomes of Patients With Severe Aortic Stenosis Discussed by the Multidisciplinary ‘‘Heart Team” According to Treatment Allocation. Heart, Lung and Circulation (2019), https://doi.org/10.1016/j.hlc.2019.02.192
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Table 1 Baseline characteristics of cohort and by treatment allocation. MHT Decision
Total
TAVI
SAVR
Medical Therapy
Number Mean age
243 80.2 8.0
200 80.2 8.3
26 80.4 6.1
17 80.4 7.3
Mean EuroSCORE II
6.4 4.6
6.5 4.7
5.3 3.6
6.7 4.3
Gender ratio % (male/female)
60/40
58/42
62/38
82/18
Previous sternotomy/Porcelain aorta
73 (30%)
70 (35%)
0
3 (18%)
Mean follow-up period (years)
2.0 1.4
1.8 1.3
2.8 1.9
2.2 1.6
Deceased at follow-up (n)
49
30
9
10
Abbreviations: MHT, multidisciplinary ‘‘Heart Team”; TAVI, transcatheter aortic valve implantation; SAVR, surgical aortic valve replacement.
Figure 1 Flow diagram of treatment allocated and received.
(n = 149), 84% (n = 21) and 54% (n = 13) at 2 years respectively). Survival outcomes following TAVI and SAVR were similar to that of the general population (Figure 4).
Discussion There are few reports evaluating the contribution of the MHT to the management of patients with severe aortic stenosis [12]. Of the 243 patients discussed over 5 years in Auckland, 82% had TAVI, 11% had SAVR and 7% were managed medically. This is in line with other published literature of MHT aortic valve treatment allocation [13], and the growing enthusiasm and ability for intermediate to high-risk patients to undergo TAVI. One key difference of our MHT is that patients must first be accepted as a surgical candidate, albeit with high risk, by the combined cardio-surgical conference before presentation to the MHT as in New Zealand TAVI is only funded for ‘‘operable” patients. The small number of
patients recommended for medical treatment had a very poor outcome, consistent with the MHT assessment that TAVI or SAVR was futile and also with the dismal natural history of untreated severe symptomatic aortic stenosis [14]. The number of patients discussed each year by the MHT is increasing, as are the number of TAVIs performed each year. There are several reasons for this. Firstly, TAVI indications have widened from those with high surgical risk to intermediate risk and are likely to expand further in the future [3–7]. Secondly, with increasing understanding and experience of the TAVI procedure the threshold for referral has fallen. The goal of the MHT is to optimally match the patient and their treatment. The excellent 2-year survival, similar to that of the general population, in those having TAVI and SAVR suggests that this has been achieved (Figure 4). However, it cannot be determined exactly what factors tilted the decision of treatment modality and whether there is true equipoise between TAVI and SAVR outcomes for selected patients due to potential bias.
Please cite this article in press as: Rea CW, et al. Characteristics and Outcomes of Patients With Severe Aortic Stenosis Discussed by the Multidisciplinary ‘‘Heart Team” According to Treatment Allocation. Heart, Lung and Circulation (2019), https://doi.org/10.1016/j.hlc.2019.02.192
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Figure 2 Trend in total number of patients discussed by the MHT and TAVI’s performed. Abbreviations: MHT, multidisciplinary ‘‘Heart Team”; TAVI, transcatheter aortic valve implantation.
Figure 3 Trends in age and EuroSCORE II over time by TAVI and SAVR. Abbreviations: TAVI, transcatheter aortic valve implantation; SAVR, surgical aortic valve replacement.
Over time, there were no significant changes in age of MHT patients undergoing TAVI and SAVR. Most patients referred to the MHT were elderly septuagenarian or octogenarian patients, with younger patients undergoing SAVR and those with too high a risk or too many co-morbidities continuing MT without TAVI consideration. On the other hand, there was a significant decrease in EuroSCORE II of patients undergoing both interventions, whilst the average age remained similar indicating a reduction in co-morbidities.
Our results illustrate the limitations in the prognostic utility of the EuroSCORE II. This score was originally derived to estimate operative mortality of patients undergoing cardiac surgery, the majority being coronary in nature but with a significant proportion having valve surgery [11]. Furthermore, only a small proportion of that derivation cohort encompassed high risk patients such as those discussed at MHT, and therefore the EuroSCORE II is less accurate in such patients. It was not designed for TAVI or medical therapy,
Please cite this article in press as: Rea CW, et al. Characteristics and Outcomes of Patients With Severe Aortic Stenosis Discussed by the Multidisciplinary ‘‘Heart Team” According to Treatment Allocation. Heart, Lung and Circulation (2019), https://doi.org/10.1016/j.hlc.2019.02.192
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Figure 4 Kaplan-Meier survival curves by treatment allocation.
and studies have shown the EuroSCORE II’s prediction of outcome following TAVI to be inferior to SAVR [15,16]. Because of this, clinicians are unable to rely solely on the EuroSCORE II for an individual patient and instead use complementary, more subjective, forms of information to reach a decision. The MHT attempts to assist this deficiency by applying multiple inputs from various clinicians with different skill sets [9]. In our patients the MHT assessment of high surgical risk was not reflected in the mean EuroScore II, which suggested that some patients were intermediate risk. This was also observed in the randomised trials. For example, the US CoreValve trial [5] of high risk patients asked the MHT to enrol patients with an estimated 30-day surgical risk of 15% or greater, guided by the Society of Thoracic Surgeons Online Risk Score (STS PROM risk score). However, the mean STS PROM score of those in the trial was 7.4% and only 15% of patients had an STS score over 10%. In both trials and the real world, the MHT takes into account risk factors for mortality and morbidity not included in the calculation of surgical risk scores. Additional factors, known to be associated with adverse outcomes after cardiac surgery, not accounted for by the EuroSCORE II include frailty, moderate renal dysfunction and porcelain aorta [17,18]. Of relevance, in our study, 35% of TAVI treated patients had undergone previous CABG as opposed to none of those assigned surgical aortic valve replacement. The need for careful assessment of frailty, disability and multi-morbidity in patients, particularly the elderly, has been highlighted by the introduction of TAVI [19]. It is important to identify those who are likely to benefit and rehabilitate to greater independence and a more active functional state and on the other hand those in whom a procedure is likely to be futile and possibly cause harm. The use of a number of tools, for example the Canadian study of Health and Ageing, Katz and poor mobility, have shown that estimates of increased
frailty were associated with poor outcomes and that use of such tools improved the performance of clinical predication models [20]. Whilst the guidelines recommend the formation of a MHT heart team to establish dialogue, consensus and case-by case discussion of patients with aortic stenosis, in essence its function has become much broader in our local context. In a publically funded health system the MHT has a potentially auditable role to maintain the local or national guidelines under which TAVI is funded. With multiple cardiologist referrers from different institutions another task is to ensure a visible maintenance of consistency in decision-making and equity of access. Its task is also to minimise the offering of TAVI to patients in whom it is likely to be futile and to constrain its availability to high or at least intermediate risk. Finally, the MHT also serves to ensure all imaging and clinical information is available in order to provisionally plan the TAVI procedure with respect to valve type, size and access. Table 2 describes the various functions of the MHT.
Table 2 Functions of the multidisciplinary ‘‘Heart Team” (MHT). Primary function Multidisciplinary dialogue and consensus Secondary functions Provide expert opinion to complement risk scores Imaging and clinical information reviewed Documentation of discussion and conclusions (audit and dissemination) Minimisation of futility Maintenance of adherence to funding policies Starting point for data collection
Please cite this article in press as: Rea CW, et al. Characteristics and Outcomes of Patients With Severe Aortic Stenosis Discussed by the Multidisciplinary ‘‘Heart Team” According to Treatment Allocation. Heart, Lung and Circulation (2019), https://doi.org/10.1016/j.hlc.2019.02.192
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Study Limitations This is a single-centre, retrospective, observational study with a relatively small number of patients assigned to SAVR or to MT. The single-arm cohort design does not permit comparison of patients who went through the MHT process with those who did not. Follow-up duration was only to a mean of 2 years. The MHT dataset currently lacks broader information in areas that may be useful for extended analyses such as operative complications, quality of life, frailty and post-procedural days in intensive care and in hospital. Such information could provide an enhanced analysis of the efficacy of the Auckland City Hospital MHT and the associated risks and benefits of the procedures.
Conclusion The majority (82%) of increased-risk patient with severe aortic valve disease discussed at MHT for consideration of TAVI were recommended to undergo TAVI. The number of patients discussed and undergoing TAVI is steadily increasing with time. Although baseline demographics and EuroSCORE II were similar between these groups, both TAVI and SAVR had survival comparable to that of the matched general population, whereas those continuing on MT had a dismal outcome. These findings suggest that the Auckland MHT process is robust, consistent and appropriately allocating a limited treatment resource.
[3]
[4]
[5]
[6]
[7]
[8]
[9] [10] [11]
[12]
[13]
[14]
Disclosures
[15]
None of the authors have any disclosures. [16]
Acknowledgement Funding to conduct this study was generously provided to Conor Rea by an A+ Charitable Trust Summer Studentship Grant.
References [1] Baumgartner H, Falk V, Bax JJ, De Bonis M, Hamm C, Holm PJ, et al. 2017 ESC/EACTS Guidelines for the management of valvular heart disease. Eur Heart J 2017;38:2739–91. [2] Nishimura RA, Otto CM, Bonow RO, Carabello BA, Erwin JP, Fleisher LA, et al. 2017 AHA/ACC focused update of the 2014 AHA/ACC guideline for the management of patients with valvular heart disease:
[17]
[18]
[19]
[20]
a report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. Circulation 2017;20 (June (135)):e1159–95. Leon MB, Smith CR, Mack M, Miller DC, Moses JW, Svensson LG, et al. Transcatheter aortic-valve implantation for aortic stenosis in patients who cannot undergo surgery. N Engl J Med 2010;363:1597–607. Smith CR, Leon MB, Mack MJ, Miller DC, Moses JW, Svensson LG, et al. Transcatheter versus surgical aortic-valve replacement in high-risk patients. N Engl J Med 2011;364:2187–98. Adams DH, Popma JJ, Reardon MJ, Yakubov SJ, Coselli JS, Deeb GM, et al. Transcatheter aortic-valve replacement with a self-expanding prosthesis. N Engl J Med 2014;370:1790–8. Reardon MJ, Van Mieghem NM, Popma JJ, Kleiman NS, Søndergaard L, Mumtaz M, et al. Surgical or transcatheter aortic-valve replacement in intermediate-risk patients. N Engl J Med 2017;376:1321–31. Leon MB, Smith CR, Mack MJ, Makkar RR, Svensson LG, Kodali SK, et al. Transcatheter or surgical aortic-valve replacement in intermediate-risk patients. N Engl J Med 2016;374:1609–20. Thourani VH, Kodali S, Makkar RR, Herrmann HC, Williams M, Babaliaros V, et al. Transcatheter aortic valve replacement versus surgical valve replacement in intermediate-risk patients: a propensity score analysis. Lancet 2016;387:2218–25. Holmes DR, Rich JB, Zoghbi WA, Mack MJ. The heart team of cardiovascular care. J Am Coll Cardiol 2013;61:903–7. Nashef SA, Roques F, Sharples LD, Nilsson J, Smith C, Goldstone AR, et al. EuroSCORE II. Eur J Cardiothorac Surg 2012;41:734–44. Statistics New Zealand. New Zealand Cohort Life Tables [Internet];[cited 15 September 2017]. Available from 2016, http://www.stats.govt.nz/ browse_for_stats/health/life_expectancy/ cohort-life-tables-info-releases.aspx. Coylewright M, Mack MM, Holmes DR, O’Gara PT. A call for an evidence-based approach to the heart team for patients with severe aortic stenosis. J Am Coll Cardiol 2015;65:1472–80. Kaier K, Gutmann A, Vach W, Sorg S, Siepe M, Moser M, et al. "Heart Team" decision making in elderly patients with symptomatic aortic valve stenosis who underwent AVR or TAVI-a look behind the curtain. Results of the prospective TAVI Calculation of Costs Trial (TCCT). Eurointervention 2015;11:793–8. Horstkotte D, Loogen F. The natural history of aortic valve stenosis. Eur Heart J 1988;9(supp E):57–64. Wang TK, Wang MT, Gamble GD, Webster M, Ruygrok PN. Performance of contemporary surgical risk scores for transcatheter aortic valve implantation: a meta-analysis. Int J Cardiol 2017;236:350–5. Biancari F, Juvonen T, Onorati F, Faggian G, Heikkinen J, Airaksinen J, et al. Meta-analysis on the performance of the EuroSCORE II and the Society of Thoracic Surgeons Scores in patients undergoing aortic valve replacement. J Cardiothorac Vasc Anesth 2014;28:1533–9. Sepehri A, Beggs T, Hassan A, Rigatto C, Shaw-Daigle C, Tangri N, et al. The impact of frailty on outcomes after cardiac surgery: a systematic review. J Thorac Cardiovasc Surg 2014;148:3110–7. Rosenhek R, Iung B, Tornos P, Antunes MJ, Prendergast BD, Otto CM, et al. ESC Working Group on Valvular Heart Disease Position Paper: assessing the risk of interventions in patients with valvular heart disease. Eur Heart J 2011;33:822–8. Puri R, Iung B, Cohen DJ, Rode´s-Cabau J. TAVI or No TAVI: identifying patients unlikely to benefit from transcatheter aortic valve implantation. Eur Heart J 2016;37:2217–25. Martin GP, Sperrin M, Ludman PF, deBelder MA, Gunning M, Townend J, et al. Do frailty measures improve prediction of mortality and morbidity following transcatheter aortic valve implantation? An analysis of the UK TAVI registry. BMJ Open 2018;8:e022543.
Please cite this article in press as: Rea CW, et al. Characteristics and Outcomes of Patients With Severe Aortic Stenosis Discussed by the Multidisciplinary ‘‘Heart Team” According to Treatment Allocation. Heart, Lung and Circulation (2019), https://doi.org/10.1016/j.hlc.2019.02.192
Heart, Lung and Circulation (2019) xx, 1–6 1443-9506/04/$36.00 https://doi.org/10.1016/j.hlc.2019.02.192
ORIGINAL ARTICLE
Characteristics and Outcomes of Patients With Severe Aortic Stenosis Discussed by the Multidisciplinary ‘‘Heart Team” According to Treatment Allocation Conor W. Rea, MBChB, Tom Kai Ming Wang, FRACP, Peter N. Ruygrok, MD, FRACP *, Karishma Sidhu, MSc, Tharumenthiran Ramanathan, PhD, FRACS, Parma Nand, FRACS, James T. Stewart, MD, FRACP, Mark W.I. Webster, FRACP Green Lane Cardiovascular Service, Auckland City Hospital, Auckland, New Zealand Received 20 February 2018; received in revised form 30 October 2018; accepted 26 February 2019; online published-ahead-of-print xxx
Background
Transcatheter aortic valve implantation (TAVI) is an alternative and effective contemporary intervention to surgical aortic valve replacement (SAVR) for patients with severe aortic valve disease at increased surgical risk. Guidelines recommend a multidisciplinary ‘‘Heart Team” (MHT) review of patients considered for a TAVI procedure, but this has been little studied. We reviewed the characteristics, treatments and outcomes of such patients reviewed by the MHT at our centre.
Methods
Data on consecutive patients with severe aortic valve stenosis discussed by the Auckland City Hospital MHT from June 2011 to August 2016 were obtained from clinical records. Patient characteristics, treatment and outcomes were analysed using standard statistical methods.
Results
Over the 5-year period 243 patients (mean age 80.2 8.0 years, 60% male) were presented at the MHT meeting. TAVI was recommended for 200, SAVR for 26 and medical therapy for 17 patients, with no significant difference in mean age (80.2 8.3, 80.4 6.1, 80.4 7.3 years, respectively) or EuroSCORE II (6.5 4.7%, 5.3 3.6%, 6.7 4.3%, respectively). Over time, there was an increase in the number of patients discussed and treated, with no change in their mean age, but the mean EuroSCORE II significantly decreased (TAVI p = 0.026, SAVR p = 0.004). Survival after TAVI and SAVR was similar to that of the age-matched general population, but superior to medical therapy p = 0.002 (93% (n = 162), 84% (n = 21) and 73% (n = 18) at one year and 85% (n = 149), 84% (n = 21) and 54% (n = 13) at 2 years, respectively).
Conclusions
An increasing number of patients were discussed at the MHT meeting with the majority undergoing TAVI, with a similar age and EuroSCORE II to those allocated SAVR or medical therapy. Survival following TAVI and SAVR was superior to medical therapy and similar to the age-matched general population. These findings suggest that the MHT process is robust, consistent and appropriately allocating a limited treatment resource.
Keywords
TAVI Aortic stenosis AVR Heart team Multidisciplinary
*Corresponding author at: Green Lane Cardiovascular Service, Auckland City Hospital, Private Bag 92024, Auckland, 1030, New Zealand, Email: PRuygro [email protected] © 2019 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.
Please cite this article in press as: Rea CW, et al. Characteristics and Outcomes of Patients With Severe Aortic Stenosis Discussed by the Multidisciplinary ‘‘Heart Team” According to Treatment Allocation. Heart, Lung and Circulation (2019), https://doi.org/10.1016/j.hlc.2019.02.192
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Introduction Surgical aortic valve replacement (SAVR) is the gold standard treatment for patients with severe symptomatic aortic valve disease [1,2]. Transcatheter aortic valve implantation (TAVI) has grown significantly over the last decade as an alternative to SAVR. Early randomised trials demonstrated the superiority of TAVI versus medical therapy (MT) in inoperable patients, and comparable to SAVR in high risk patients [3–5]. More recent trials, in intermediate risk patients, have found that transfemoral TAVI with newergeneration valves achieve similar [6], or better outcomes than SAVR [7,8]. Clinical decision-making for selecting the optimal treatment modality is an important rationale for the contemporary concept of the multidisciplinary ‘‘Heart Team” (MHT) [1,9], developed to establish dialogue, consensus and caseby-case recommendation of the most appropriate treatment strategy. It may be composed of cardiologists, cardiothoracic surgeons, anaesthetists, intensivists, radiologists, geriatricians and nurse coordinators, with the intention of obtaining multidisciplinary input and expertise to create and foster robust decision making. Guidelines recommend the implementation of the MHT for managing aortic valve disease, but there remains a paucity of literature describing the characteristics and impact of such a process [1]. TAVI is restricted in the New Zealand public health care system to high-risk but operable patients, and was introduced to Auckland City Hospital in 2011 handin-hand with the MHT discussion process. We reviewed the characteristics, treatment allocation and outcomes of all patients with severe aortic valve disease being considered for TAVI and discussed by the MHT.
Methods This retrospective study reviewed all patients discussed at the MHT meeting since its introduction with TAVI at Auckland City Hospital in April 2011 until August 2016. All patients were first presented at the regional cardiosurgical conference and accepted for SAVR, albeit with high risk, to ensure only operable patients are considered for TAVI. The MHT team consists of the presenting, interventional (at least two) and imaging cardiologists, cardiac surgeons, anaesthetists, cardiovascular intensivists, geriatricians and TAVI nurse co-ordinator, meeting 2-weekly to monthly. The meeting is chaired by an independent cardiologist not involved in TAVI procedures. Clinical baseline and procedural characteristics and outcomes were obtained from clinical records and documented minutes of all MHT meetings, and the EuroSCORE II [10] calculated for all patients. Treatment allocation consisted of TAVI, SAVR or medical therapy. Patient mortality data was obtained from the National Mortality Collection and was complete up to 15 October 2016 and thus was the endpoint for all data collection. The period of follow-up for all patients
was from the time of discussion at the MHT to either the time of their death or data collection from the National Mortality Collection, should that individual still be alive. Mean survival time was the primary outcome of interest. Standard statistical analyses were performed. The Wilcoxon Rank-Sum Test was used to compare quantitative variables and the Fisher’s Exact Test for categorical variables. Kaplan Meier survival curves were constructed according to treatment received. Those patients who lived overseas and, thus, for whom no follow-up was available (n = 11), died whilst awaiting allocated treatment (n = 5) and those still awaiting allocated treatment at the time of analysis (n = 3) were excluded. A log-rank test was performed to compare survival. The projected survival of the general age-matched population in New Zealand was obtained [11]. Statistical analyses were performed using the statistical package SAS version 9.3. All tests were two-sided with p < 0.05 considered statistically significant.
Results There were 243 patients presented at MHT during the study period. The population consisted of patients referred from eight New Zealand District Health Boards (Waitemata 77, Counties Manukau 62, Auckland City 47, Northland 32, Southern 11, other 3) and two overseas countries (Tahiti 10, other 1). Mean age was 80.2 8.0 years and 60% of the cohort was male, with an average EuroSCORE II of 6.4 4.6. Of the 243 patients discussed at the MHT, TAVI was recommended for 200 (82%), SAVR for 26 (11%) and MT for 17 (7%) patients, with no significant difference in mean age (80.2 8.3, 80.4 6.1, 80.4 7.3, respectively) or EuroSCORE II (6.5 4.7, 5.3 3.6, and 6.7 4.3, respectively) between the three groups. Table 1 lists baseline characteristics by treatment allocation cohort. Of the 200 patients assigned to TAVI, three crossed over to the SAVR group, six to the MT group and four died awaiting treatment. Of the 26 patients for SAVR, zero crossed over to TAVI, three to MT and one died awaiting treatment. Of the 17 patients who were assigned to MT, one crossed over to TAVI and zero to SAVR (Figure 1). The mean time from MHT discussion to treatment was 60 days for TAVI patients, 87 days for SAVR patients and 0 days for those allocated to MT as they continued their usual therapy. Of the 188 patients who actually received TAVI, the approach was 147 transfemoral, 24 transaortic and 17 transapical. Figure 2 illustrates the number of patients discussed at MHT and undergoing TAVI per 6month period. Both increased steadily over time. The mean period of follow-up was 2.0 1.4 years. Correlation analyses of the trend in mean EuroSCORE II of both TAVI and SAVR over the 5-year study period showed a significant decrease over time (TAVI p = 0.026, SAVR p = 0.004) but age remained similar (Figure 3). Survival was similar for TAVI and SAVR patients with both being significantly longer than those receiving MT p = 0.002 (93% (n = 162), 84% (n = 21) and 73% (n = 18) at 1 year and 85%
Please cite this article in press as: Rea CW, et al. Characteristics and Outcomes of Patients With Severe Aortic Stenosis Discussed by the Multidisciplinary ‘‘Heart Team” According to Treatment Allocation. Heart, Lung and Circulation (2019), https://doi.org/10.1016/j.hlc.2019.02.192
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Table 1 Baseline characteristics of cohort and by treatment allocation. MHT Decision
Total
TAVI
SAVR
Medical Therapy
Number Mean age
243 80.2 8.0
200 80.2 8.3
26 80.4 6.1
17 80.4 7.3
Mean EuroSCORE II
6.4 4.6
6.5 4.7
5.3 3.6
6.7 4.3
Gender ratio % (male/female)
60/40
58/42
62/38
82/18
Previous sternotomy/Porcelain aorta
73 (30%)
70 (35%)
0
3 (18%)
Mean follow-up period (years)
2.0 1.4
1.8 1.3
2.8 1.9
2.2 1.6
Deceased at follow-up (n)
49
30
9
10
Abbreviations: MHT, multidisciplinary ‘‘Heart Team”; TAVI, transcatheter aortic valve implantation; SAVR, surgical aortic valve replacement.
Figure 1 Flow diagram of treatment allocated and received.
(n = 149), 84% (n = 21) and 54% (n = 13) at 2 years respectively). Survival outcomes following TAVI and SAVR were similar to that of the general population (Figure 4).
Discussion There are few reports evaluating the contribution of the MHT to the management of patients with severe aortic stenosis [12]. Of the 243 patients discussed over 5 years in Auckland, 82% had TAVI, 11% had SAVR and 7% were managed medically. This is in line with other published literature of MHT aortic valve treatment allocation [13], and the growing enthusiasm and ability for intermediate to high-risk patients to undergo TAVI. One key difference of our MHT is that patients must first be accepted as a surgical candidate, albeit with high risk, by the combined cardio-surgical conference before presentation to the MHT as in New Zealand TAVI is only funded for ‘‘operable” patients. The small number of
patients recommended for medical treatment had a very poor outcome, consistent with the MHT assessment that TAVI or SAVR was futile and also with the dismal natural history of untreated severe symptomatic aortic stenosis [14]. The number of patients discussed each year by the MHT is increasing, as are the number of TAVIs performed each year. There are several reasons for this. Firstly, TAVI indications have widened from those with high surgical risk to intermediate risk and are likely to expand further in the future [3–7]. Secondly, with increasing understanding and experience of the TAVI procedure the threshold for referral has fallen. The goal of the MHT is to optimally match the patient and their treatment. The excellent 2-year survival, similar to that of the general population, in those having TAVI and SAVR suggests that this has been achieved (Figure 4). However, it cannot be determined exactly what factors tilted the decision of treatment modality and whether there is true equipoise between TAVI and SAVR outcomes for selected patients due to potential bias.
Please cite this article in press as: Rea CW, et al. Characteristics and Outcomes of Patients With Severe Aortic Stenosis Discussed by the Multidisciplinary ‘‘Heart Team” According to Treatment Allocation. Heart, Lung and Circulation (2019), https://doi.org/10.1016/j.hlc.2019.02.192
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Figure 2 Trend in total number of patients discussed by the MHT and TAVI’s performed. Abbreviations: MHT, multidisciplinary ‘‘Heart Team”; TAVI, transcatheter aortic valve implantation.
Figure 3 Trends in age and EuroSCORE II over time by TAVI and SAVR. Abbreviations: TAVI, transcatheter aortic valve implantation; SAVR, surgical aortic valve replacement.
Over time, there were no significant changes in age of MHT patients undergoing TAVI and SAVR. Most patients referred to the MHT were elderly septuagenarian or octogenarian patients, with younger patients undergoing SAVR and those with too high a risk or too many co-morbidities continuing MT without TAVI consideration. On the other hand, there was a significant decrease in EuroSCORE II of patients undergoing both interventions, whilst the average age remained similar indicating a reduction in co-morbidities.
Our results illustrate the limitations in the prognostic utility of the EuroSCORE II. This score was originally derived to estimate operative mortality of patients undergoing cardiac surgery, the majority being coronary in nature but with a significant proportion having valve surgery [11]. Furthermore, only a small proportion of that derivation cohort encompassed high risk patients such as those discussed at MHT, and therefore the EuroSCORE II is less accurate in such patients. It was not designed for TAVI or medical therapy,
Please cite this article in press as: Rea CW, et al. Characteristics and Outcomes of Patients With Severe Aortic Stenosis Discussed by the Multidisciplinary ‘‘Heart Team” According to Treatment Allocation. Heart, Lung and Circulation (2019), https://doi.org/10.1016/j.hlc.2019.02.192
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Figure 4 Kaplan-Meier survival curves by treatment allocation.
and studies have shown the EuroSCORE II’s prediction of outcome following TAVI to be inferior to SAVR [15,16]. Because of this, clinicians are unable to rely solely on the EuroSCORE II for an individual patient and instead use complementary, more subjective, forms of information to reach a decision. The MHT attempts to assist this deficiency by applying multiple inputs from various clinicians with different skill sets [9]. In our patients the MHT assessment of high surgical risk was not reflected in the mean EuroScore II, which suggested that some patients were intermediate risk. This was also observed in the randomised trials. For example, the US CoreValve trial [5] of high risk patients asked the MHT to enrol patients with an estimated 30-day surgical risk of 15% or greater, guided by the Society of Thoracic Surgeons Online Risk Score (STS PROM risk score). However, the mean STS PROM score of those in the trial was 7.4% and only 15% of patients had an STS score over 10%. In both trials and the real world, the MHT takes into account risk factors for mortality and morbidity not included in the calculation of surgical risk scores. Additional factors, known to be associated with adverse outcomes after cardiac surgery, not accounted for by the EuroSCORE II include frailty, moderate renal dysfunction and porcelain aorta [17,18]. Of relevance, in our study, 35% of TAVI treated patients had undergone previous CABG as opposed to none of those assigned surgical aortic valve replacement. The need for careful assessment of frailty, disability and multi-morbidity in patients, particularly the elderly, has been highlighted by the introduction of TAVI [19]. It is important to identify those who are likely to benefit and rehabilitate to greater independence and a more active functional state and on the other hand those in whom a procedure is likely to be futile and possibly cause harm. The use of a number of tools, for example the Canadian study of Health and Ageing, Katz and poor mobility, have shown that estimates of increased
frailty were associated with poor outcomes and that use of such tools improved the performance of clinical predication models [20]. Whilst the guidelines recommend the formation of a MHT heart team to establish dialogue, consensus and case-by case discussion of patients with aortic stenosis, in essence its function has become much broader in our local context. In a publically funded health system the MHT has a potentially auditable role to maintain the local or national guidelines under which TAVI is funded. With multiple cardiologist referrers from different institutions another task is to ensure a visible maintenance of consistency in decision-making and equity of access. Its task is also to minimise the offering of TAVI to patients in whom it is likely to be futile and to constrain its availability to high or at least intermediate risk. Finally, the MHT also serves to ensure all imaging and clinical information is available in order to provisionally plan the TAVI procedure with respect to valve type, size and access. Table 2 describes the various functions of the MHT.
Table 2 Functions of the multidisciplinary ‘‘Heart Team” (MHT). Primary function Multidisciplinary dialogue and consensus Secondary functions Provide expert opinion to complement risk scores Imaging and clinical information reviewed Documentation of discussion and conclusions (audit and dissemination) Minimisation of futility Maintenance of adherence to funding policies Starting point for data collection
Please cite this article in press as: Rea CW, et al. Characteristics and Outcomes of Patients With Severe Aortic Stenosis Discussed by the Multidisciplinary ‘‘Heart Team” According to Treatment Allocation. Heart, Lung and Circulation (2019), https://doi.org/10.1016/j.hlc.2019.02.192
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Study Limitations This is a single-centre, retrospective, observational study with a relatively small number of patients assigned to SAVR or to MT. The single-arm cohort design does not permit comparison of patients who went through the MHT process with those who did not. Follow-up duration was only to a mean of 2 years. The MHT dataset currently lacks broader information in areas that may be useful for extended analyses such as operative complications, quality of life, frailty and post-procedural days in intensive care and in hospital. Such information could provide an enhanced analysis of the efficacy of the Auckland City Hospital MHT and the associated risks and benefits of the procedures.
Conclusion The majority (82%) of increased-risk patient with severe aortic valve disease discussed at MHT for consideration of TAVI were recommended to undergo TAVI. The number of patients discussed and undergoing TAVI is steadily increasing with time. Although baseline demographics and EuroSCORE II were similar between these groups, both TAVI and SAVR had survival comparable to that of the matched general population, whereas those continuing on MT had a dismal outcome. These findings suggest that the Auckland MHT process is robust, consistent and appropriately allocating a limited treatment resource.
[3]
[4]
[5]
[6]
[7]
[8]
[9] [10] [11]
[12]
[13]
[14]
Disclosures
[15]
None of the authors have any disclosures. [16]
Acknowledgement Funding to conduct this study was generously provided to Conor Rea by an A+ Charitable Trust Summer Studentship Grant.
References [1] Baumgartner H, Falk V, Bax JJ, De Bonis M, Hamm C, Holm PJ, et al. 2017 ESC/EACTS Guidelines for the management of valvular heart disease. Eur Heart J 2017;38:2739–91. [2] Nishimura RA, Otto CM, Bonow RO, Carabello BA, Erwin JP, Fleisher LA, et al. 2017 AHA/ACC focused update of the 2014 AHA/ACC guideline for the management of patients with valvular heart disease:
[17]
[18]
[19]
[20]
a report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines. Circulation 2017;20 (June (135)):e1159–95. Leon MB, Smith CR, Mack M, Miller DC, Moses JW, Svensson LG, et al. Transcatheter aortic-valve implantation for aortic stenosis in patients who cannot undergo surgery. N Engl J Med 2010;363:1597–607. Smith CR, Leon MB, Mack MJ, Miller DC, Moses JW, Svensson LG, et al. Transcatheter versus surgical aortic-valve replacement in high-risk patients. N Engl J Med 2011;364:2187–98. Adams DH, Popma JJ, Reardon MJ, Yakubov SJ, Coselli JS, Deeb GM, et al. Transcatheter aortic-valve replacement with a self-expanding prosthesis. N Engl J Med 2014;370:1790–8. Reardon MJ, Van Mieghem NM, Popma JJ, Kleiman NS, Søndergaard L, Mumtaz M, et al. Surgical or transcatheter aortic-valve replacement in intermediate-risk patients. N Engl J Med 2017;376:1321–31. Leon MB, Smith CR, Mack MJ, Makkar RR, Svensson LG, Kodali SK, et al. Transcatheter or surgical aortic-valve replacement in intermediate-risk patients. N Engl J Med 2016;374:1609–20. Thourani VH, Kodali S, Makkar RR, Herrmann HC, Williams M, Babaliaros V, et al. Transcatheter aortic valve replacement versus surgical valve replacement in intermediate-risk patients: a propensity score analysis. Lancet 2016;387:2218–25. Holmes DR, Rich JB, Zoghbi WA, Mack MJ. The heart team of cardiovascular care. J Am Coll Cardiol 2013;61:903–7. Nashef SA, Roques F, Sharples LD, Nilsson J, Smith C, Goldstone AR, et al. EuroSCORE II. Eur J Cardiothorac Surg 2012;41:734–44. Statistics New Zealand. New Zealand Cohort Life Tables [Internet];[cited 15 September 2017]. Available from 2016, http://www.stats.govt.nz/ browse_for_stats/health/life_expectancy/ cohort-life-tables-info-releases.aspx. Coylewright M, Mack MM, Holmes DR, O’Gara PT. A call for an evidence-based approach to the heart team for patients with severe aortic stenosis. J Am Coll Cardiol 2015;65:1472–80. Kaier K, Gutmann A, Vach W, Sorg S, Siepe M, Moser M, et al. "Heart Team" decision making in elderly patients with symptomatic aortic valve stenosis who underwent AVR or TAVI-a look behind the curtain. Results of the prospective TAVI Calculation of Costs Trial (TCCT). Eurointervention 2015;11:793–8. Horstkotte D, Loogen F. The natural history of aortic valve stenosis. Eur Heart J 1988;9(supp E):57–64. Wang TK, Wang MT, Gamble GD, Webster M, Ruygrok PN. Performance of contemporary surgical risk scores for transcatheter aortic valve implantation: a meta-analysis. Int J Cardiol 2017;236:350–5. Biancari F, Juvonen T, Onorati F, Faggian G, Heikkinen J, Airaksinen J, et al. Meta-analysis on the performance of the EuroSCORE II and the Society of Thoracic Surgeons Scores in patients undergoing aortic valve replacement. J Cardiothorac Vasc Anesth 2014;28:1533–9. Sepehri A, Beggs T, Hassan A, Rigatto C, Shaw-Daigle C, Tangri N, et al. The impact of frailty on outcomes after cardiac surgery: a systematic review. J Thorac Cardiovasc Surg 2014;148:3110–7. Rosenhek R, Iung B, Tornos P, Antunes MJ, Prendergast BD, Otto CM, et al. ESC Working Group on Valvular Heart Disease Position Paper: assessing the risk of interventions in patients with valvular heart disease. Eur Heart J 2011;33:822–8. Puri R, Iung B, Cohen DJ, Rode´s-Cabau J. TAVI or No TAVI: identifying patients unlikely to benefit from transcatheter aortic valve implantation. Eur Heart J 2016;37:2217–25. Martin GP, Sperrin M, Ludman PF, deBelder MA, Gunning M, Townend J, et al. Do frailty measures improve prediction of mortality and morbidity following transcatheter aortic valve implantation? An analysis of the UK TAVI registry. BMJ Open 2018;8:e022543.
Please cite this article in press as: Rea CW, et al. Characteristics and Outcomes of Patients With Severe Aortic Stenosis Discussed by the Multidisciplinary ‘‘Heart Team” According to Treatment Allocation. Heart, Lung and Circulation (2019), https://doi.org/10.1016/j.hlc.2019.02.192