Discongruence Index: predictor of prosthesis size loss after transcatheter aortic valve replacement

Introduction

Prosthesis under-expansion has been associated with higher rates of complications and worse long term outcome after transcatheter aortic valve replacement (TAVR). The objective of the current study was to assess the value of a new “Discongruence index”, to predict the percentage of prosthesis size loss (compared to its nominal size). The “discongruence index” is obtained from the relation between transcatheter valve size and the patient body surface area.

Methods

A total of 247 consecutive patients with severe aortic stenosis that underwent TAVR with balloon expandable Edwards-Sapiens prosthesis or CoreValve Revalving system at our institution were included. The “Discongruence index” was calculated pre-procedurally as the ratio: selected transcatheter valve size (mm) / body surface area (cm2). Two-dimensional transesophageal echocardiography images were studied in the 120–135° plane after the prosthesis deployment, and the maximum anteroposterior diameter was measured (in millimeters). From this measurement was obtained the percentage of prosthesis size loss (compared to the prosthesis nominal size).

Results

Mean age was 82±6 years and 102 patients (41.3%) were men. Mean aortic valvular area before TAVR was 0,87±3,8 cm2, (indexed 0,36±0,1 cm2) and the mean aortic gradient 49,1±16,9 mmHg. Mean prosthesis maximum deployment was 18,9±2,7 mm; absolute loss of prosthesis size compared to nominal 6,5±2,8 mm and the percentage loss of prosthesis size 25.1±9,5%. The “Discongruence index” was predictor of the percentage of prosthesis size loss (y = 5,7650 + 1,3010x, p<0,001), see figure.

Conclusions

The “Discongruence index” is a useful tool to predict the percentage of prosthesis size loss after TAVR. This new index should be taken into consideration in the selection of transcatheter valve sizes to avoid prosthesis under-expansion.

Funding Acknowledgement

Type of funding sources: None. Figure 1

Impact of right ventricular function and ventriculo-arterial coupling in prognosis after percutaneous edge-to-edge mitral repair

Background

Left ventricular systolic function is widely used as selection criteria for appropriateness of percutaneous edge-to-edge mitral repair in patients with significant mitral regurgitation (MR) and high surgical risk. Although right ventricular (RV) systolic function and ventriculo-arterial coupling (VAC) have demonstrated its relevance in heart failure prognosis as well, few data are available regarding this procedure.

Purpose

To study the value of baseline RV function and VAC determined by transthoracic echocardiogram (TTE) on imaging and clinical prognosis.

Methods

We evaluated all the consecutive patients in which a percutaneous mitral edge-to-edge repair with the MitraClip system was performed between 2010 and 2020 in our tertiary university hospital. Baseline RV function was considered depressed if TAPSE <16 mm, tissue Doppler S'<9.5 cm/s or fractional area change (FAC) <35% on TTE. VAC was calculated as ratio of TAPSE by pulmonary artery systolic pressure (PASP) from the same studies. Follow-up echocardiographic measurements were evaluated and clinical events were collected from medical records.

Results

We included 88 patients (64.8% males, 76±10 years) with MR grade ≥3. MR etiology was classified as functional 44.3%, organic in 35.2% and mixed in 20.5%. Previous to the procedure left ventricular systolic function was mildly depressed (LVEF 44.5±15.3%) and 33 patients (37.5%) showed an impaired RV systolic function. At 6 months TTE the prevalence of RV dysfunction lower to 27.3%. Patients with initial RV systolic dysfunction showed greater improvement in TAPSE (3.2 vs −0.53 mm; p=0.052) and FAC (8 vs 0.2%; p=0.016) at 6 months compared to those with normal baseline RV function. However, this variable was not associated with any relevant clinical event during the follow up. Baseline VAC demonstrated a significant inverse correlation with change in TAPSE (r −0.42; p=0.018), FAC (r −0.37; p=0.024) and S' (r −0.52; p=0.041) at 6 months. Among patients with initial RV impairment, VAC was lower in those who persisted with RV systolic dysfunction at 6 months (0.41 vs 0.49; p=0.054). Moreover, VAC was significantly associated with NYHA class ≥3 (0.48 vs 0.63; p=0.042) and cardiovascular hospitalization (0.53 vs 0.63; p=0.07), with a correlation with number of admissions (r −0.27; p=0.053).

Conclusion

In a percutaneous mitral edge-to-edge repair population previous presence of RV systolic dysfunction was not associated with clinical events during the follow up. Conversely, VAC was able to identify RV systolic function recovery and was associated with functional class and cardiovascular hospitalizations.

Funding Acknowledgement

Type of funding sources: None.

Correlation between cardiac magnetic resonance feature tracking derived left ventricular strain and morphological characteristics of non-ischemic dilated cardiomyopathy at baseline and follow-up

Background

Left ventricular (LV) strain from echocardiography is a known useful predictor of LVEF recovery in non-ischemic dilated cardiomyopathy (NIDCM). More recently, feature tracking (FT) has allowed LV myocardial deformation analysis using conventional cardiac magnetic resonance (CMR) cine sequences.

Purpose

Our aim is to establish the correlation between LV strain values from CMR-FT at diagnosis and morphological parameters at baseline and during follow-up.

Methods

Consecutive patients with NIDCM who underwent CMR were retrospectively collected. All the studies were performed in a 1.5 Tesla magnet following a standard acquisition protocol of conventional SSFP cine sequences in long and short axis. Global longitudinal, circumferential and radial strain (GLS, GCS and GRS, respectively) were obtained with a dedicated FT software. Correlation with CMR morphological parameters at baseline were evaluated. Likewise, in the cases with follow-up echocardiogram association between FT LV strain and evolution of morphofunctional variables was explored.

Results

CMR-FT strain analysis was performed in 98 patients (age 68±13 years, 72% males) with NIDCM. They showed severe LV dilatation (LVEDVi= 133.6±33.4 mL/m2) and systolic dysfunction (LVEF= 29.5±9.6%) at baseline. Myocardial fibrosis was detected in 38.8% of the patients with late gadolium enhancement (LGE) sequence. All the basal CMR morphological characteristics were significantly correlated with FT strain analysis (Table), even more markedly for GCS. However, there was no association of baseline morphofunctional parameters with LGE. An echocardiogram was performed in 85.7% of the patients during the follow-up (2.4 [1.8–3.4] years), with an LVEF >50% in the 25.5% of the cases. These patients with preserved LVEF in the evolution showed better GCS (−9 vs −7.1%; p=0.019) at baseline, with no differences in the other FT LV strain parameters. Despite less fibrosis in LGE (16.1% vs 37.7%; p=0.037), none of the baseline morphofunctional CMR parameters (LVEF, LVEDVi...) were associated with systolic function restoration. In multivariate analysis, GCS was the only independent predictor (OR 1.16; p=0.045) of LVEF recovery among imaging variables.

Conclusions

All the FT derived LV strain values were correlated with the degree of basal morphofunctional involvement in NIDCM. Furthermore, GCS emerged as an independent imaging predictor of LV systolic function restoration in our series.

Funding Acknowledgement

Type of funding sources: None. Table 1. Correlation between myocardial deformation values by feature tracking and morphofunctional variables in basal CMR.

Clinical relevance of cardiac magnetic resonance feature tracking derived left ventricular strain in nonischemic dilated cardiomyopathy

Background

Left ventricular (LV) myocardial deformation analysis with echocardiography has shown an additive value for risk stratification in nonischemic dilated cardiomyopathy (NIDCM). However, scarce data is available with the new cardiac magnetic resonance (CMR) technique feature tracking, which allows strain evaluation from conventional cine sequences.

Purpose

Our aim is to analyze prognostic relevance of FT in NIDCM

Methods

Consecutive patients with NIDCM diagnosis and CMR at diagnosis were retrospectively included. LV global longitudinal, circumferential and radial strain (GLS, GCS and GRS, respectively) were obtained from standard CMR cine sequences with a dedicated FT software. Their association with a composite endpoint (heart failure admission, implantable cardioverter defibrillator in secondary prevention, and death) was evaluated.

Results

FT derived strain was obtained in 98 patients (68±13 years, 72% males) with NIDCM, mostly idiopathic (75.5%). The vast majority showed a severely dilated LV (LVEDVi= 133.6±33.4 mL/m2) with severely impaired systolic function (LVEF= 29.5±9.6%), and in 38.8% of the cases fibrosis was demonstrated in late gadolium enhancement (LGE). During a 3.2 [2.2–4] years follow-up 25.5% had an admission due to heart failure, 5.1% received an implantable cardioverter defibrillator in secondary prevention, and 10.2% died. Only a trend towards worse GCS values (−7.1 vs −8.5%; p=0.10) was noted among patients with heart failure hospitalization. Mortality was associated with poorer GCS (−5.9 vs −7.9%; p=0.012) and GLS (−6.9 vs −9.6%; p=0.051) values, whereas GRS was not related with any prognostic variable. Exclusively GCS was associated with the composite endpoint (−6.7 vs −8.2%; p=0.035). Considering other morphological parameters with prognostic relevance (LVEF and LVEDVi), GCS was the only independent predictor (OR 1.15; p=0.038). A cut-off point <−8.2% was able to identify those patients with a worse clinical evolution (Figure, Log Rank 4.6; p=0.032)

Conclusions

In our series LV myocardial deformation analysis with FT has shown prognostic relevance in NIDCM, especially GCS determination.

Funding Acknowledgement

Type of funding sources: None. Figure 1

Cardiac mechanics as predictors of left ventricular reverse remodelling in patients with dilated non-ischemic cardiomyopathy

Background and purpose

The appearance of left ventricular reverse remodelling (LVRR) is associated with a better prognosis in patients with dilated non-ischemic cardiomyopathy (DCM).

Our aim was to identify cardiac imaging parameters, including speckle tracking by transthoracic echocardiography (TTE) and feature tracking by CMR, associated with LVRR in a prospective cohort of patients with DCM.

Methods

From 2014 to 2021, 182 patients with DCM and left ventricle ejection fraction (LVEF) <40% were prospectively evaluated in our hospital.

LVRR was defined as an increase in LVEF ≥10 points or absolute LVEF ≥50%, associated with a reduction in left ventricular end- diastolic diameter ≥10%.

Patients underwent multimodality imaging evaluation including CMR with a 1.5 Tesla scanner, and TTE. Cardiac mechanics, including global longitudinal strain (GLS), strain rate (SR) and mechanical dispersion (MD) were measured.

Results

Median age of our cohort was 62.3 (14.4) years, and 67.7% were male.

Most patients (>90%) were treated with beta-blockers or RASS blockers, and 67% with mineralocorticoid receptor antagonists. 30% had cardiac resynchronization therapy (CRT) and 37% had ICD as primary prevention. Mean LVEF was 31.3%. During a mean follow-up period of 35.9 (35.4) months, 38.3% of patients had LVRR.

Age and gender distribution were similar in both groups. Regarding cardiovascular risk factors and pharmacological treatment, no differences were found between patients with and without LVRR. Baseline CRT therapy was not associated with LVRR (22.6% vs 34.7%; p=0.249). However, there was a trend towards higher LVRR in those who received CRT during follow-up 18.8% vs 0%; p=0.069).

Patients who experienced LVRR had lower basal LVEF (23.4% vs 29%; p<0.008), as well as poorer RV function, including lower RVEF (40.5% vs 51%; p=0.006) and lower TAPSE (16 mm vs 19 mm; p=0.021). Regarding cardiac mechanics, those patients with lower GLS (−9% vs −12%; p=0.001), and higher MD (73 mm vs 55 mm; p=0,050) had LVRR more frequently during follow-up. The presence of a left bundle branch block (LBBB) contraction pattern by strain was associated with higher rate of LVRR (83.3% vs 30.4%; p=0.011). The burden of fibrosis measured by LGE with CMR was not associated with LVRR (14% vs 12%; p=NS).

Patients with LVRR had a lower cardiovascular mortality (3.3 vs 14.3%; p=0.117), lower mortality due to heart failure (0% vs 12.2%; p=0.046), less heart failure hospitalizations (20% vs 46.9%; p=0.016), and a lower incidence of ventricular tachyarrhythmias (3.3% vs 18.4%; p=0.051).

Conclusions

LVRR in patients with DCM receiving optimized medical therapy is associated with a better prognosis. Imaging parameters, including a lower basal LVEF, RVEF, GLS and higher MD, as well as LBBB echo pattern, were associated with a higher frequency of LVRR, and might help to identify patients who could benefit from CRT/and may be helpful to stratify patients's risk.

Funding Acknowledgement

Type of funding sources: None.

P6456Role of cardiac imaging in the prediction of ventricular arrythmias, heart failure and death in dilated non-ischemic cardiomyopathy with severe left ventricular systolic disfunction

Background and purpose

Dilated non-ischemic cardiomyopathy (DCM) is associated with an increased risk of cardiac events. Implantable Cardioverter Defibrillator (ICD) is recommended in DCM with severe left ventricular ejection fraction impairment, but the evidence of its usefulness is somewhat controversial. We evaluated the predictive value of myocardial fibrosis measured by cardiac magnetic resonance (CMR) and of global longitudinal strain (GLS) in the incidence of adverse cardiac events.

Methods

From 2009 to 2019, sixty-six patients with DCM were evaluated. CMR with a 1.5 Tesla scanner was performed, and the presence and extent of late gadolinium enhancement (LGE) was blindly assessed. GLS was measured using speckle-tracking 2D echocardiography. We examined the incidence of sustained ventricular arrhythmias (SVA, including appropriate anti-tachycardia pacing and shocks), admissions due to heart failure (HF) and all-cause mortality.

Results

62.1% of the patients were male, with a median age of 63.8 years. 50.0% had cardiac resynchronization therapy and 73.9% had ICD as primary prevention therapy. Median LVEF was 25.7%.

Median follow-up was 32 months. In that period, 10.6% of patients died, 25.8% had hospital admissions due to HF, and 9.2% had SVA. A burden of LGE over 14% was independently associated with higher risk of SVA (3.0% vs 19.2%, p=0.041). This cut-off value had a sensitivity of 83.3% and a negative predictive value of 97.0%. LGE was not associated with higher risk of HF admissions (27.3% vs 23.1%, p=0.731) or death (9.1% vs 11.5%, p=0.757).

On the other hand, GLS was not associated with higher risk of SVA (8.7% vs 4.55% for a cut-off value of −10.6%, p=0.577), HF admissions (26.1% vs 30.4%, p=0.743) or death (8.7% vs 8.7%, p=1.00).

Table 1. Main etiologies of DCM Causes N (%) Idiopathic 43 (65.2) Alcoholic 6 (9.1) Chemotherapy 4 (6.1) Non-compaction 4 (6.1) Familiar 3 (4.6) Thoracic radiotherapy 2 (3.0) Chagas disease 2 (3.0)

Conclusions

The burden of myocardial fibrosis measured by LGE is a high sensitive marker for the development of SVA. However, is not a predictive tool for HF admissions or all-cause mortality. GLS was not associated with the incidence of cardiac events in this population.

Bone Fractures After Cardiac Transplantation

OBJECTIVE

Bone loss and bone fractures are disabling complications after heart transplantation. Severe bone loss happens mainly during the first year posttransplantation. Steroids and cyclosporine alter bone metabolism in several ways. To counterbalance these effects, antiresorptive therapy is provided to these patients. The objective of this study was to assess the frequency of bone fractures after heart transplantation, considering previous comorbidities, immunosuppressive therapy, and osteoprotective treatment.

METHODS

From 1993 to 2005, 443 consecutive heart transplant recipients were followed for the occurrence of bone fractures, immunosuppressive therapy, clinical conditions, and antiresorptive treatment.

RESULTS

There were 41 fractures in 34 patients (7.6%, group I). The remainder of patients formed group II. Fractures commonly involved the lumbar spine. Postmenopausal women had more fractures than other patients (20.6% vs 7.8%, P = .02). When the initial immunosuppressive regimen included tacrolimus, fractures did not happen (P = .01, vs other regimens). Osteoprotective therapy was administered to 91.2% of patients in group I and 79% in group II (P = .08). Mean interval from transplantation to the first fracture was 1131.5 days. Overweight patients had a 61.8% incidence of fracture.

CONCLUSIONS

Our series showed a low frequency of bone fractures. Postmenopausal women and overweight patients had more fractures. An initial immunosuppressive regimen using tacrolimus was associated with lower fracture rates.