Academic Editor: Peter A. McCullough
This article belongs to the Special Issue: Interventions for the failing left ventricle (https://rcm.imrpress.com/EN/subject/listSubjectChapters.do?subjectId=1612753815968).
Left ventricular (LV) aneurysm following acute myocardial infarction (MI)
represents a less common complication, but with worse clinical outcomes.
Ventricular surgical reconstruction is not always the intervention of choice due
to high surgical risk. There were proposed less invasive LV aneurysm exclusion
techniques such as the less invasive ventricular enhancement (LIVE) procedure.
Our paper represents the first systematic approach to investigate the efficacy
and safety of LIVE procedure using Revivent TC
Left ventricular (LV) aneurysm following acute myocardial infarction (MI) represents a less common complication in the current era of percutaneous coronary interventions (PCI) and thrombolytic therapy, but with worse short- and long-term clinical outcomes.
Epidemiological data regarding the incidence of LV aneurysms in patients with acute MI are discrepant. One study [1], with a small cohort of patients (n = 158), observed that 22% of them developed LV aneurysm during one-year follow-up. However, a recent study [2] with an impressive number of patients with acute MI (n = 11,622,528) observed that 0.2% of them had LV aneurysm. Notably, patients with LV aneurysm had a greater incidence of ventricular arrhythmias (17.6% vs 8.0%), mechanical complications (2.6% vs 0.2%), cardiac arrest (7.1% vs 5.0%), pump failure (26.3% vs 16.1%), and cardiogenic shock (10.0% vs 4.8%). Also, these patients developed LV thrombus and stroke more frequently. Even if patients with LV aneurysms represent a small population, they should benefit from a more individualized approach, including follow-up and treatment strategy, including various surgical and percutaneous interventions.
A state-of-the-art review pointed out criteria that could help identify patients
who would benefit from surgery. Surgical ventricular reconstruction could be
indicated in the case of anterior or posterior MI, LV end-systolic volume index
(LVESVI)
One of such interventions is represented by the less invasive ventricular
enhancement (LIVE) procedure, which implies a percutaneous approach and a
minithoracotomy on the left side [4]. An anchor system, Revivent TC
Our systematic review aims to assess the efficacy and safety of the LIVE procedure reported in clinical trials to treat patients with heart failure and LV aneurysm.
The present systematic review was conducted according to the updated Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) [5], as illustrated in the PRISMA checklist (Supplementary Table 1). The protocol was primarily registered on PROSPERO (CRD42021248643).
We performed a literature search from inception to April 2021 in MEDLINE (PubMed), Embase, and Cochrane library databases, with no time interval restriction (Supplementary Table 2). We also examined Google Scholar and references of the cited publications to detect additional studies. A registry of clinical trials (ClinicalTrials.gov) was screened for supplementary data. We provided entire search strategies for all databases and total records retrieved in Supplementary Table 2, in line with the PRISMA search checklist. For MEDLINE and Embase databases, the search was restricted to trials involving humans. The following combinations of MeSH terms and essential keywords were used in the search process: “left ventricular aneurysm exclusion”, “Revivent”, “less-invasive ventricular enhancement”, and “left ventricular reconstruction”.
Studies were considered for inclusion in the present systematic review if they
enrolled adult humans aged
Two independent investigators extracted from included studies in the final systematic review the following data: first author, year, study design, number of patients enrolled and their age, LV dimensions and volumes, outcomes investigated, and duration of follow-up. Data were presented as percentage, the corresponding 95% confidence interval (CI) when available, mean value with standard deviation, and P-value. Any discrepancies in data extraction were solved by consensus.
The quality of observational studies that did not include a control group was assessed using a National Institutes of Health (NIH) [7]. This tool contains 14 key questions which guide critical appraisal of the overall study quality.
We searched the prespecified databases and retrieved 4409 references. After excluding duplicate citations and records based on title or abstract, 52 studies were left for eligibility assessment. Five studies met the inclusion criteria and were finally included in the present systematic review, as 16 abstract-only papers and 31 citations which did not report outcomes of interest were excluded. The flow diagram of the screening process was presented in Fig. 1.
Flow diagram of the selection process.
General characteristics of analyzed studies, including design, population,
outcomes, clinical setting, and follow-up, were presented in Table 1 (Ref. [8, 9, 10, 11, 12]). All studies
[8, 9, 10, 11, 12] had an observational, non-randomized design, and three of them
were performed in multiple centers [8, 9, 12]. Also, two studies enrolled
patients prospectively [9, 11]. As this hybrid procedure was addressed to a
specific population, all patients included in clinical studies had a history of
MI and a reduced LVEF,
Author, year | Design | Patients, No | Age, median/mean | Setting | Outcomes | Follow-up |
Klein et al, 2019 [8] | Observational, multicentre | 9 | 60 |
-History of anteroseptal MI with akinetic or dyskinetic scar; | -NYHA class | Before hospital discharge |
-LVEF |
-LVEF | |||||
-NYHA class |
-LV dimensions and volumes | |||||
-BSA 2.0 |
-Sphericity index | |||||
-Diabetes mellitus: 2 patients (22%) | -Presence of MR and TR | |||||
-RV perforation | ||||||
-Hospital mortality | ||||||
Klein et al, 2019 [9] | Observational, prospective, multicentre | 89 | 60.4 |
-History of MI | -LV volumes and LVEF | 6 months and 1 year |
-Akinesia and/or dyskinesia of anteroseptal, anterolateral walls and/or apical regions; | -NYHA class | |||||
-LVEF |
-6-minute walk test | |||||
-NYHA class II–IV; | -Quality of life score | |||||
-LVESVI |
-Changes in MR | |||||
-BMI 28.9 |
-Length of hospital and ICU stay | |||||
-Creatinine 1.04 |
-Survival at 12 months | |||||
-Diabetes mellitus: 16 patients (19%) | -NT-proBNP | |||||
Loforte et al, 2019 [10] | Observational, retrospective, single centre | 7 | 72 |
-History of anteroseptal MI | -LV volumes and | 189.7 |
-LVEF |
-LVEF | |||||
-LVESVI |
-Sphericity index | |||||
-NYHA class III–IV | -Length of hospital and ICU stay | |||||
-BSA 1.9 |
-RV perforation | |||||
-NYHA class | ||||||
Wang et al, 2020 [11] | Observational, prospective, single centre | 26 | 57.8 |
-Transmural anteroseptal or apical scar | -LV dimensions and volumes | 1, 3, 6 and 9 months |
-LVEF |
-LVEF | |||||
-LVESVI |
-6-minute walk test | |||||
-NYHA class II–IV | -NYHA class | |||||
-BMI 21.2 |
-NT-proBNP | |||||
-Diabetes mellitus: 10 patients (38.5%); | ||||||
-Hypertension: 9 patients (34.6%) | ||||||
Wechsler et al, 2013 [12] | Observational, multicentre | 11 | N/A | -Large anteroseptal scars | LV volumes | 1, 3, 6, and 12 months |
-LVESVI | ||||||
-LVEF | ||||||
-NYHA class II–IV | ||||||
BMI, body mass index; BSA, body surface area; ICU, intensive care unit; LV, left ventricle; LVEF, left ventricular ejection fraction; LVESVI, left ventricular end-systolic volume index; MI, myocardial infarction; MR, mitral regurgitation; NT-proBNP, N-terminal pro B-type natriuretic peptide; NYHA, New York Heart Association; RV, right ventricle; TR, tricuspid regurgitation. |
Almost all studies included patients with NYHA class II-IV [8, 9, 11, 12] and with LVESVI
Study | Outcomes | Results | ||
Klein et al, 2019 [8] | Preoperatively | Postoperatively | ||
LVEF (%) | 28 |
40 |
P | |
LVESVI (mL/m |
53 |
30 |
P | |
LVEDVI (mL/m |
75 |
45 |
P = 0.001 | |
Sphericity index | 0.5 |
0.5 |
P = 0.7 | |
NYHA class | 2.7 |
2.3 |
P = 0.58 | |
RV perforation | 1 patient | |||
Hospital mortality | 0% | |||
ICU stay (days) | 2 (IQR, 1–46) | |||
Klein et al, 2019 [9] | Baseline | At 12 months | ||
LVEF (%) | 29 |
34 |
P | |
LVESVI (mL/m |
74 |
54 |
P | |
LVEDVI (mL/m |
106 |
80 |
P | |
NYHA class | 2.6 |
1.9 |
P | |
6-minute walk test (m) | 363 |
416 |
P | |
MLHFQ score | 39 |
26 |
P | |
MR grade | 1.12 |
0.86 |
||
NT-proBNP (pg/mL) | 1175.1 |
913.9 |
P = 0.365 | |
Survival at 12 months (%) | 90.6 (95% CI, 84.6–97.0) | |||
Loforte et al, 2019 [10] | Preoperatively | Postoperatively | ||
LVEF (%) | 22.8 |
35 |
P = 0.001 | |
LVESVI (mL/m |
93.2 |
52.1 |
P | |
LVEDVI (mL/m |
137.2 |
78 |
P = 0.001 | |
Sphericity index | 0.5 |
0.4 |
P = 0.621 | |
NYHA class (follow-up) | 3.4 |
1.4 |
P = 0.001 | |
ICU stay (days) | 7.8 (range, 1–22) | |||
RV perforation | 1 patient | |||
Wang et al, 2020 [11] | Preoperatively | Follow-up | ||
LVEDD-AP (mm) | 63.6 |
|||
LVESVI (mL/m |
84.8 |
65.6 |
P | |
LVEDVI (mL/m |
107.8 |
90.5 |
P | |
LVEF (%, Echocardiography) | 35.6 |
45.9 |
P | |
LVEF (%, CMR) | 28.9 |
38.6 |
P | |
6-minute walk test (m) | 368.8 |
461.5 |
P | |
NT-proBNP (pg/mL) | 758.6 |
508.4 |
P = 0.916 | |
NYHA class | 2.7 |
1.7 |
P | |
MACE | 2 patients (7.7%) | |||
Wechsler et al, 2013 [12] | At baseline | At 6 months | ||
LVESVI (mL/m |
72.6 |
46.2 |
P | |
LVEDVI (mL/m |
102.5 |
73.2 |
P | |
At baseline | At 12 months | |||
LVESVI (mL/m |
72.6 |
43.9 |
P | |
LVEDVI (mL/m |
102.5 |
69.5 |
P | |
CMR, cardiac magnetic resonance; ICU, intensive care unit; LV, left ventricle; LVEDD, left ventricular end-diastolic antero-posterior diameter; LVEDVI, left ventricular end-diastolic volume index; LVEF, left ventricular ejection fraction; LVESVI, left ventricular end-systolic volume index; MACE, major adverse cardiovascular events; MLHFQ, Minnesota Living with Heart Failure Questionnaire; MR, mitral regurgitation; NT-proBNP, N-terminal pro B-type natriuretic peptide; NYHA, New York Heart Association; RV, right ventricle. |
The effects of this less-invasive procedure on LVESVI and LV end-diastolic
volume index (LVEDVI) were consistent across studies. Klein et al. [8]
observed that postoperative LV volume reduction was statistically significant
(P
In one international multicentre study [9] with longer follow-up period (12
months), less-invasive ventricular reconstruction determined a significant LVESVI
and LVEDVI reduction (respectively, P
Similar results were reported in another study with a smaller population [10].
Loforte et al. observed that LV reconstruction was associated with a
reduction in LV volumes and LVEF (P = 0.001). Also, patients’ NYHA class
was improved during follow-up (P = 0.001). The sphericity index remained
unchanged postoperatively (P = 0.621), concordant with data from studies
above mentioned. RV perforation was observed in one patient and required
sternotomy. The authors used a 3.0
In a recent prospective study, Wang et al. [11] reported that in the
case of patients who underwent LV reconstruction using Revivent TC
Wechsler et al. [12] documented the LV reconstruction procedure’s
efficiency with Revivent TC
NIH tool designed for observational studies was used to assess the included studies, illustrated in Supplementary Table 3. In general, the quality was judged to be fair, as none of the studies was randomized or blinded.
To the best of our knowledge, this systematic review is the first one to
investigate the efficacy and safety of LIVE procedure using Revivent TC
Graphical illustration summarizing the Revivent TC
Data regarding surgical LV reconstruction in patients with ischemic cardiomyopathy are discrepant in the literature. In general, LV aneurysmectomy is performed concomitant with other open-surgery procedures involving heart valves or coronary arteries. A comprehensive preoperative evaluation is mandatory, including assessment of heart failure symptoms, LV volumes, and cavity measurements using echocardiography or CMR, as well as scar tissue transmural extension. Surgical LV reconstruction could be indicated in highly selected patients and performed in experienced centers [3].
In some cases, surgery is contraindicated due to induced cardioplegia, severe RV dysfunction, or LV restrictive diastolic dysfunction [3]. Other contraindications for surgical LV reconstruction include extensive coronary artery disease not suitable for revascularization, multiple MI areas, and significant pulmonary hypertension [13]. These patients are at high risk of adverse cardiovascular events, and therapeutic resources are limited to guidelines-directed heart failure medical treatment.
The new hybrid intervention, LIVE procedure, using a percutaneous approach and a left minithoracotomy, emerged as a therapeutic option for LV aneurysm exclusion. Significantly, patients with high surgical risk could benefit from this procedure as it is performed without induced cardioplegia, cardiopulmonary bypass circuit, and ventriculotomy [10, 12].
The LIVE procedure with Revivent TC
Data provided by studies available only in the abstract were similar, reducing LV volumes and LVEF improvement [14, 15, 16, 17]. Moreover, the LIVE procedure was associated with 88.7% and 87.1% survival rates at 1- and 2-years follow-up, respectively [14]. A comparable survival rate at two years (88%) was found in a multicentre trial [18]. One study [17] compared the LIVE procedure’s efficacy with optimal medical therapy and revealed that LVEF was improved at follow-up only in patients treated invasively.
The mainstay of the LIVE procedure is represented by careful patient selection.
Clinical studies included in our systematic review enrolled patients with prior
MI, anteroseptal aneurysm, reduced LVEF, LVESVI
Notably, patients received oral anticoagulant therapy with Warfarin (target international normalized ratio, 2.0–2.5) for three months. Therefore, patients at high risk of bleeding or contraindications to anticoagulant therapy might not benefit from the LIVE procedure [9, 11]. Besides, patients with documented left atrial or LV thrombus could receive anticoagulant therapy for 2–3 months before the intervention; otherwise, the LIVE procedure is contraindicated [9].
Another important aspect regarding the procedure is represented by the number of internal and external anchor pairs required. On the one hand, anchors should occlude aneurysm entirely; on the other hand, they could lead to RV restriction with subsequent low cardiac output, as documented in one study [8]. RV restriction was solved by removing one pair of anchors using left thoracotomy as in the initial intervention. Also, the anchor system could cause RV perforation [8, 10], a mechanical complication requiring classic sternotomy.
Arrhythmic events, in particular sustained ventricular arrhythmias, may be caused by the LIVE procedure due to mechanical stimulation of healthy myocardium during anchors implantation [10, 19, 20]. Therefore, a primed cardiopulmonary bypass (CPB) machine or extracorporeal membrane oxygenation (ECMO) are recommended to be readily available [10] in case of emergency. However, data are still scarce based on the small series currently reported [12], and the documented arrhythmogenic risk is mainly theoretical. To gain more evidence-based insights, with more extended follow-up data, we do still have to wait for the results of the CONFIGURE-HF (NCT01568164) and REVIVE-HF trials (NCT03845127) [8].
In addition to arrhythmic events and RV restriction and perforation, other
reported complications are stroke, ventricular septal defect, tricuspid valve
chordae, or leaflets damage [10, 8]. These possible complications may be due to
insufficient training as this novel procedure requires consistent coaching and
guidance. For this reason, Loforte et al. [10] wisely concluded:
“This is why the Revivent
Results are limited by the small number of patients enrolled and the observational design of the studies included, which did not have a control arm (medical therapy or surgical LV reconstruction). Also, the learning curve can be a source of variability for both outcomes and complications rate [9, 11].
Causes of the ventricular aneurysm, other than ischemic, are traumatic,
infective, congenital, or idiopathic etiologies, systemic arterial hypertension,
use of steroids, and non-steroidal anti-inflammatory drugs, Chagas disease, or
sarcoidosis [21, 22]. 85% to 90% of the aneurysms occur in ischemia settings
[21], explaining the lack of published studies to date reporting outcomes of the
LIVE procedure in settings other than post-myocardial infarction. However, there
are currently no theoretical reasons to limit the LIVE method for any aneurysms
other than the absence of evidence-based data. Thereby, we are looking forward to
the BioVentrix Revivent TC
The LIVE procedure represents a new hybrid intervention for LV anteroseptal aneurysm exclusion in patients with ischemic cardiomyopathy. This technique was associated with excellent outcomes not only in terms of LV volumes, LVEF, and functional status but also in terms of survival rate. The LIVE procedure appears to be a promising and appropriate treatment strategy for a complex condition, which could extend the indication of LV aneurysm exclusion in the future. However, more studies with a control arm are needed, focusing mainly on major adverse cardiovascular events and long-term mortality.
CB and AB conceived and designed the study; CB and AB performed the search; CB and AB analyzed the data; CB, AB and IVP wrote the paper; AB and MC revised the paper.
Not applicable.
Thanks to all the peer reviewers for their opinions and suggestions.
This research received no external funding.
The authors declare no conflict of interest.