Author + information
- Niklas Schofer, MD∗ ()
- Department of General and Interventional Cardiology, University Heart Center Hamburg, Hamburg, Germany
- ↵∗Address for correspondence:
Dr. Niklas Schofer, University Heart Center Hamburg, Martinistrasse 52, 20246 Hamburg, Germany.
Transcatheter aortic valve replacement (TAVR) has emerged as the first-choice therapy for patients with severe aortic stenosis (AS) who cannot undergo open heart surgery or are at high surgical risk (1,2). Thus, TAVR opened a new treatment option for many AS patients who had been denied for (surgical) aortic valve replacement in the pre-TAVR era (3). Although open heart surgery and/or cardiopulmonary bypass grafting is not contraindicated per se in patients with AS and concomitant active malignancy, it is associated with a higher rate of periprocedural complications, such as bleeding and infections (4). Accordingly, some cancer patients with severe, symptomatic AS are referred for percutaneous treatment. This leaves a challenging decision for the heart team because it has to balance the prognostic impact of one malignant disease (cancer) against another (AS). The current guidelines recommend treatment of AS patients if life expectancy is beyond 12 months (1,2). However, life expectancy in oncology patients is often difficult to predict (5), and removal of severe AS might allow for a more aggressive cancer treatment, which could result in an improved prognosis even for some patients with advanced cancer. So far, limited data with conflicting results are available regarding oncology patients undergoing TAVR (6,7). Watanabe et al. (6) reported outcome of 47 cancer patients from the OCEAN-TAVI (Optimized Transcatheter Valvular Intervention–Transcatheter Aortic Valve Implantation) registry and found similar 12-month survival in these patients compared with patients without cancer. By contrast, Mangner et al. (7) assessed the outcome of 99 cancer patients after TAVR performed in a single center and showed a higher 12-month mortality rate in comparison to cancer-free patients.
In this issue of JACC: Cardiovascular Interventions by using multicenter-derived registry data, Landes et al. (8) compared outcome after TAVR among patients with versus without active cancer. The authors found that patients with active malignancy undergoing TAVR have similar short-term (30 day), but worse mid-term (12 month) outcome after TAVR compared with those without malignancy due to an excess of noncardiac mortality. In fact, one-half of the deaths in the cancer group were cancer related. Importantly, the difference in outcome between patients with and without cancer remained significant after applying a propensity score–matched comparison. Interestingly, Landes et al. (8) found no difference in outcome between patients in limited cancer stages (stage I or II) and cancer-free patients. By contrast, patients in advanced cancer stages (III or IV) had a significantly poorer prognosis. Accordingly, cancer stage III/IV was the strongest independent predictor for mortality, with a hazard ratio of 3.2, whereas cancer stage I/II was not predictive for mortality.
The authors are to be congratulated for better characterizing this subset of TAVR patients with heretofore very limited information for clinical decision making. Great efforts were needed to distill the registry data of 8,497 procedures from 18 TAVR centers worldwide and produce the largest dataset (N = 222) of oncology patients undergoing TAVR.
What do we learn from this information from Landes et al. (8)?
First, the proportion of active cancer patients among the overall TAVR population has increased over time with a prevalence of 4% in recent years. As demonstrated in the current study as well as by others (9), the primary diagnosis of cancer becomes apparent with the pre-procedural CT scan before TAVR in a substantial number of cases. Thus, with the global trend in further expanding the indication for TAVR, it is likely that the interdisciplinary heart team will have to face decision making for this complex subset of TAVR patients more often in the future.
Second, the prognosis of TAVR patients with cancer is strongly and primarily determined by the progression or consequences of the malignancy. The present study provides evidence that it is crucial to involve specialized oncologists in the heart team decision before TAVR to accurately define the stage of malignancy and the estimated life expectancy. In this regard, it is important that only those cancer patients who present with true symptomatic severe AS are considered for TAVR because patients with asymptomatic AS are not limited in their intermediate-term prognosis by the aortic valve disease (2). Because there can be an overlap of symptoms between AS and neoplastic disease—for example, dyspnea—isolated balloon aortic valvuloplasty might be helpful in occasional cases as a diagnostic tool to distinguish between AS and cancer-related symptoms.
Last, although in the present study the calculated surgical risk, as assessed by the Society of Thoracic Surgeons (STS) score, was lower in the cancer group, outcome in these patients was worse compared with noncancer patients. This indicates that the attributable risk of cancer is not represented in currently available surgical risk scores. Applying additional risk scores to cancer patients, for example, frailty assessment by using the “Katz index” or the “Kanofski performance status,” might improve risk assessment in this patient population (5,10).
As acknowledged by the authors, there are some important limitations inherent in their analysis:
1. Among the cancer group, a wide variety of cancer types with different grades of malignancy were present, and outcome was not stratified by cancer type. It is not surprising that there is evidence that certain, less malignant types of cancer, such as prostate cancer or chronic lymphocytic leukemia, are associated with better survival among TAVR patients compared with other cancer types (7).
2. The study does not provide data on quality of life after TAVR. This would be an important outcome measures for patients with advanced cancer receiving palliative therapy.
3. The most important unanswered question is whether TAVR compared with optimal medical treatment (OMT) can improve prognosis in oncology patients with severe AS. In order to answer this question appropriately, a randomized controlled trial is needed. However, such a study would be difficult to conduct given the heterogeneity of cancer patients, and it might be prohibitive from an ethical point of view. Still, at least a retrospective propensity score–matched comparison of cancer patients treated with either TAVR or OMT would be valuable.
4. Moreover, such an analysis should in times of health care cost restrictions analyze the cost-effectiveness of TAVR versus OMT among oncology patients.
So in the end, does TAVR in patients with active cancer make sense?
It seems that it does, at least for those patients with early-stage cancer. However, more data on outcome according to the type of cancer, quality of life, and symptom relief after TAVR as well as the cost-effectiveness of TAVR compared with OMT will have to be obtained. Until then, the decision whether oncology patients with severe AS should receive TAVR remains an individual judgment based on interdisciplinary expert opinion.
↵∗ Editorials published in JACC: Cardiovascular Interventions reflect the views of the authors and do not necessarily represent the views of JACC: Cardiovascular Interventions or the American College of Cardiology.
Dr. Schofer has received travel compensation from Edwards Lifesciences, Boston Scientific, and St. Jude Medical; and speaking honoraria from Boston Scientific.
- 2019 American College of Cardiology Foundation
- Nishimura R.A.,
- Otto C.M.,
- Bonow R.O.,
- et al.
- Watanabe Y.,
- Kozuma K.,
- Hioki H.,
- et al.
- Mangner N.,
- Woitek F.J.,
- Haussig S.,
- et al.
- Landes U.,
- Iakobishvili Z.,
- Vronsky D.,
- et al.