DOI: https://doi.org/10.21203/rs.3.rs-23783/v1
Objectives: The purpose of this study was to clarify the influence of introduction of transcatheter aortic valve replacement (TAVR)on patients with aortic stenosis(AS) undergoing non-cardiac surgery.
Methods: Thirty-four patients with severe AS diagnosed by preoperative evaluation for non-cardiac surgery were reviewed and compared in following two categories. First,patient’s profile and surgical risk were compared between pre-TAVR group (n=10) and post-TAVR group (n=24)according to before or after the introduction of TAVR. Second, completion rate of non-cardiac surgery and interval between two operation were compared between surgical aortic valve replacement(AVR)patients before introduction of TAVR (pre-AVR group (n=10)), AVR patientsafter introduction of TAVR (post-AVR (n=12)), and TAVR patients (TAVR group (n=12)).
Results: Ageand Japan score were higherin post-TAVR group than in pre-TAVR group. Malignancy was the most common non-cardiac disease (80%) in pre-TAVR group, however, orthopedic disease became the most common (50%) in post-TAVR group. Completion rate of non-cardiac operation in pre-AVR, post-AVR and TAVR group were 70%, 33%, and 75% (post-AVR vs. TAVR: p=0.010), and interval between two operations were 129±98 days, 87±40 days and 27±15 days, respectively (pre AVR vs. TAVR: p=0.034 and post AVR vs. TAVR: p=0.025).In Post-TAVR group, AVR was selected because of unfit condition for TAVR in 5 out of 12 patients.
Conclusions:After introduction of TAVR, more senile and high-risk patients became the candidate for two staged operation and orthopedics became the most common non-cardiac disease. Innovation of transcatheter valvular interventionsand expansion of indication for currently evaluated as “unfit for TAVR” might be crucial issue for non-cardiac surgery with severe AS.
Preexisting aortic stenosis (AS) is a high risk for non-cardiac surgery [1, 2]. Guidelines from the American College of Cardiology and the American Heart Association (ACC/AHA) have recommended aortic valve replacement (AVR) before non-cardiac surgery [3]. However, elder patients, especially with numerous co-morbid conditions or frail patients, tend to refuse two successive major operations.
Recently, transcatheter aortic valve replacement (TAVR) had emerged as an alternative option for high-risk patients with symptomatic severe AS who are unable to undergo surgical AVR. The purpose of this study was to clarify the influence of introduction of TAVR on patient’s background, type of non-cardiac disease, completion rate of non-cardiac surgery and interval between the two operations.
This study complies with the Declaration of Helsinki, and was approved by the Institutional Review Board. In this retrospective study, total of 161 patients with severe AS who underwent surgical intervention between April 2011 and May 2019 were reviewed, and 34 patients with severe AS who diagnosed during the preoperative evaluation for elective non-cardiac surgery were enrolled in this study. TAVR was introduced in our institute from October 2015, and whether to perform surgical AVR or TAVR was discussed by heart team comprised of cardiologists and cardiac surgeon.
Aortic valve area, peak flow velocity and mean aortic valve pressure gradient, as well as left ventricular ejection fraction were extracted from the echocardiographic database. Severe AS was defined using current echocardiographic criteria: aortic valve area ≤ 1 cm2, peak systolic flow velocity ≥ 4 m/s, or mean gradient ≥ 40 mmHg [4]. Therapeutic options are also discussed for patients with low flow, low pressure gradient AS, i.e., mean gradient < 40 mmHg and left ventricular ejection fraction ≤ 40%. Baseline characteristics of patients were collected from medical records, and telephone questioning to the referral physicians.
First, patient’s profile and surgical risk were compared between pre-TAVR group (n = 10); patients before introduction of TAVR (April 2011 ~ September 2015, n = 10) and post-TAVR group (n = 24); patients after introduction of TAVR (October 2015 ~ May 2019). Japan score was used as risk score which predicts preoperative mortality in Japanese subjects [5]. Second, completion rate of non-cardiac surgery and interval between the two operations were compared between pre-AVR group (n = 10); who underwent AVR before introduction of TAVR, post-AVR group (n = 12); who underwent AVR after introduction of TAVR, and TAVR group (n = 12); who underwent TAVR.
Statistical analysis was performed using JMP Pro 13 (SAS Inc., NC, USA), and the demographic and clinical data were expressed as mean ± standard deviation or number (%). Baseline differences in categorical variables were tested using the Pearson χ2 test, while analysis of variance was used for comparing differences in means among the groups. Values of p < 0.05 were considered statistically significant.
Annual number of patients who underwent AVR or TAVR due to severe AS were 20.9 cases/year before introduction of TAVR and 18.6 cases/year after introduction of TAVR. And, annual number of patients who were consulted to the department of cardiovascular surgery due to severe AS diagnosed by preoperative evaluation of non-cardiac disease for each time period were 1.5 cases/year and 6.9 cases/year, respectively (Fig. 1).
Age distribution is shown in Fig. 2. In pre-TAVR group, 80 s were 20% and there was no patient over 90 years old. However, in post-TAVR group, 54% of patients was 80 s and 4.6% was 90 s.
Patient’s profile in two groups is shown in Table 1. Patients in pre-TAVR group were significantly older and had smaller body surface area than post-TAVR group. Also, Japan score was significantly higher in post-TAVR group than pre-TAVR group, and 17% patients of post TAVR group had more than 8% of Japan score (Fig. 3). Although there was no statistical significance in existence of cardiac symptoms, more patients had more than New York Heart Association class II in post-TAVR group. In post-TAVR group, 45% of patients underwent TAVR.
Diagnosis of non-cardiac operation are; malignancy in 8/10 (80%) and orthopedics in 2/10 (20%) in pre-TAVR group, and malignancy in 9/24 (38%), orthopedics in 12/24 (50%) and others 3/24 (13%; acute cholelithiasis, rectum prolapse, and strangulation of the sigmoid colon) in post-TAVR group (Fig. 4).
Compared with pre-AVR group, TAVR group showed higher age and smaller body surface area, and there was no statistical difference between pre-AVR group and post-AVR group in age and body surface area (Table 2). However, both post-AVR group and TAVR group had higher Japan score compared with pre-AVR group (p < 0.001 in both comparisons).
Completion rate of two operations in three groups were as follows; 70% in pre-AVR, 33% in post-AVR, and 75% in TAVR group. There was statistical significance between TAVR group and post-AVR group in completion rate (p = 0.010). Interval period between two operations were shown in Fig. 5. TAVR group had shorter interval than both pre-AVR and post-AVR group. Also, all patients in TAVR group underwent second operation within 60 days after TAVR.
Reason for AVR selection in post-AVR group was; low risk for AVR in 7 patients, and anatomical unfit conditions for TAVR in 5 patients, in those, 3 patients required concomitant cardiac procedure (two vessel coronary artery bypass in one, and mitral valve replacement in two), and 2 patients were on chronic hemodialysis (HD). Completion rate of non-cardiac surgery was 57% when AVR was selected due to low risk, however, no patient underwent non-cardiac surgery when AVR was selected due to unfit condition for TAVR (p = 0.081)
Patients’ age became apparently older after introduction of TAVR. Around 60% of post-TAVR group were elder than 80 years old, and orthopedic disease became the most major non-cardiac disease after introduction of TAVR. This phenomenon is quite understandable because both AS and orthopedic disease, like degenerative arthritis disease, are related to aging. Before TAVR ear, many patients with severe AS who considered orthopedic operations might have abandoned without referring to cardiac surgeons.
Surgical risk became higher after introduction of TAVR reflected by increased age and co-morbidities. There was almost two-fold increase in Japan score after introduction of TAVR, and 17% of patients had more than 8% of Japan score. As a result, there were patient subgroup who should have undergo AVR due to unfit conditions for performing TAVR, even though TAVR was preferable in the light of co-morbid conditions or frailty.
There are three representative unfit conditions for TAVR. First, there are patients with anatomically unfavorable for TAVR. Some bicuspid valves with calcified raphe or unfavorable calcified pattern, or patients with extreme aorta pathologies or diffuse peripheral arterial disease are not feasible for current TAVR procedure. Second, patients with significant mitral valve disease may develop heart failure during or after non-cardiac surgery if they are only treated by TAVR. More than moderate mitral regurgitation [6] showed adverse long-term outcome after TAVR. Mitra Clip concomitant with TAVR [7] is an alternative option, which requires future clinical studies for its safety and appropriateness. Third category is patients with HD. Recent reports on TAVR for HD patients showed high early mortality [8, 9], and reimbursement for TAVR in HD patients is not approved in Japan. However, TAVR may be considered if the durability and effectiveness of prosthetic valve in HD patients would be demonstrated in the near future.
The role of TAVR in patients undergoing non-cardiac surgery is to reduce the operative risk during and after non-cardiac surgery, and also to shorten the interval between the two operations as well. In PARTNER 3 trial, patients who underwent TAVR had more rapid improvement in NYHA class and 6-minutes-walk than those who underwent AVR, which seems to be valuable advantage in patients planning for non-cardiac surgery [10]. In patients with malignancy, short interval between the two operations is especially preferred due to progression of the disease, and also, TAVR may have some advantages in avoidance of the spread and growth of cancer cells caused by cardiopulmonary bypass [11]. However, in order to establish the patient selection of TAVR, especially for younger patients with malignancy, further studies are required.
After introduction of transcatheter aortic valve replacement (TAVR), more senile and high-risk patients became the candidate for two staged operation and orthopedics became the most common non-cardiac disease. TAVR showed advantage in shortening the interval between two operations. Existence of patients with unfit conditions for TAVR is a crucial problem, and future innovation of transcatheter valvular interventions and expansion of indication are expected.
aortic stenosis
the American College of Cardiology
the American Heart Association
Aortic valve replacement
transcatheter aortic valve replacement
patients before introduction of transcatheter aortic valve replacement
patients after introduction of transcatheter aortic valve replacement
who underwent aortic valve replacement before introduction of aortic valve replacement
who underwent aortic valve replacement after introduction of aortic valve replacement
Hemodialysis
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The authors have no conflict of interest.