Introduction
Surgical ventricular restoration (SVR) has been developed for patients with end-stage heart failure which is refractory to guideline-directed heart failure therapy in Japan, the United States of America, and Europe, owing to a shortage of donors [
1‐
4]. SVR procedures modify the left ventricular shape with ventricular volume reduction, entailing resection or exclusion of stiff segments of akinetic scar or relatively compliant dyskinetic scar [
5].
The landmark Surgical Treatment for Ischemic Heart Failure (STICH) trial showed no benefit of SVR from the standpoint of the overall survival in ischemic heart disease. However, some researchers believe that the STICH trial may have failed to show an improvement in survival by SVR because the surgery did not make the ventricle small enough [
5,
6]. A small number of hospitals have still continued to perform SVR, particularly in Italy and Japan. According to previous reported studies, the rates of survival, and recurrent heart failure were acceptable after SVR; survival rate of 82.4% at 8 years in the ischemic cardiomyopathy group and postoperative New York Heart Association (NYHA) class ≤ II, more than 80% at a mean follow-up period of 3 years and 66% at 8 years in the dilated cardiomyopathy group [
5,
7].
However, some patients may develop heart failure after successful SVR at later follow-up [
8]. This phenomenon is mainly caused by recurrent remodeling and reduced contraction of the left ventricle.
During the past decades, a continuous flow left ventricular assist device (Cf-LVAD) therapy has been a treatment option in advanced heart failure, with improving outcomes around the world [
9,
10]. In particular, modern generation LVADs are relatively small implantable centrifugal pumps, and the successful attribution boosted the number of devices implantation as bridge to transplant (BTT) and destination therapy strategy [
11‐
13]. At present, cf-LVAD implantation seems to be a feasible option as a life-saving procedure for recurrent heart failure with failed SVR along with heart transplantation.
However, an efficacy and feasibility of VAD therapy were barely investigated, due to scarce clinical experience, and there are no clear recommendations for patients with a prior history of SVR [
14,
15]. Cf-LVAD implantation may be challenging because these patients have a complex left ventricular apical anatomy that may hinder the decision of optimal inflow cannula position and angle. This is because cf-LVAD implantation in some patients after SVR with patch repair may require removal of the patch and reconstruction of the left ventricle for the proper position and direction of a left ventricular inflow cannula.
The aim of the present study was to review our experience with cf-LVAD therapy in patients with a prior SVR and provide clinical outcome and follow-up data, including mortality and adverse events.
Discussion
We successfully implanted five types of cf-LVAD in patients who had undergone SVR, including EVCCP, SAVE, and PRP with pupillary muscle approximation. To our knowledge, this is the first study to report the results after LVAD implantation following various types of SVR.
Cf-LVAD implantation improves the survival and quality of life of patients with heart failure. However, there are limited reports of VAD therapy in patients with prior SVR surgery. Therefore, the aim of this study was to assess feasibility of implantation surgery and the incidence of complications, outcomes, and safety of cf-LVAD therapy in this cohort. Several factors can make cf-LVAD implantation after SVR extremely challenging, such as the altered apical anatomy and the presence of an endoventricular patch.
Previously, Palmen et al. published a case series describing their experience in seven patients with a history of SVR (EVCPP procedure) who had VAD implants (HVAD, Medtronic) [
14]. After a follow-up of 20 ± 16 months, they reported that all seven patients were alive without any VAD complication. Interestingly, the Dacron patch implanted in the EVCPP procedure was completely removed with cardiac arrest in all patients, because the remaining left ventricular cavity was estimated to be too small to accommodate the inflow cannula of the LVAD without interference with LVAD inflow and suction of the mitral valve apparatus. The limitations in their study were as follows: (1) A prior SVR was limited to the EVCPP procedure, (2) only HVAD was implanted, and (3) the follow-up period after LVAD implantation was short. In our cohort, the patients underwent all types of SVR, including SAVE with an anteroseptal Dacron patch, EVCPP with a patch in apical portion, and PRP with pupillary muscle approximation. Additionally, implanted LVAD types composed of five device types (Table
3). The follow-up time (median 39 months (IQR; 35–55, range 10–71 months)) in our cohort was longer; wherein all patients survived and three (50%) patients could finally receive heart transplantation. As a result, our patients had effective left ventricle unloading and the long durability in failed SVR (Table
5).
While removal of the endoventricular Dacron patch may be effective in improving the position of the inflow cannula, it is not always necessary for LVAD implantation [
15]. We did not need to remove the Dacron patch in patients after SAVE and EVCPP procedures. Most patients with recurrent symptomatic heart failure after failed SVR showed dilated left ventricular dimension again (Table
2). Due to the recurrent dilated left ventricular dimension, the optimal inflow cannula position could be easily explored by direct epicardial and transoesophageal echocardiography, and device apical cuff anastomosis could be decided. Moreover, epicardial echocardiography could increase the success rate of this procedure [
13]. However, in the above-described fashion, we could implant two types of LVADs (EVAHEART and Jarvik 2000) in left ventricle positions to allow acceptable circulatory flow.
Leaving the Dacron patch in place seems to have some advantages. First, the LVAD implantation is performed with a beating heart in the routine fashion. Therefore, the surgical procedure is not complicated and is quicker. Second, myocardium damage can be reduced. This can reduce the frequency of postoperative atrial or ventricular arrhythmia, and may decrease the risk of right heart failure. Third, the left ventricular hole after the removal of Dacron patch is too large and the tissue around the hole is fragile. Therefore, there may be difficulty in controlling the bleeding around the inflow cannula. For these reasons, we routinely performed both intraoperative transoesophageal and epicardial echocardiography in all cases in order to determine the optimal position of the inflow cannula. As a result, we could perform cf-LVAD implantation in a safe fashion (Supplement 1).
Careful attention should be paid while deciding the appropriate surgical strategy. If preoperative TTE and chest CT with contrast show signs of wedge thrombus around the apical area or Dacron patch, removing the Dacron patch and Fontan stitch may be a choice of optimal surgical strategy for an inspection of the left ventricular cavity.
Limitations
There are several limitations to our study. This was a retrospective, single-center study with a limited number of patients. Even though this study does not provide generalized statements, we were still able to report good outcomes for this cohort.
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