Aortic Stenosis, a Left Ventricular Disease: Insights from Advanced Imaging

Epicardial fat tissue, a hidden enemy against the early recovery of left ventricular systolic function after transcatheter aortic valve implantation

Background

Epicardial fat tissue (EFT) is an active organ that can affect cardiac function and structure through endocrine, paracrine, and proinflammatory mechanisms. We hypothesized that greater thickness of EFT may harm the recovery of left ventricular (LV) systolic function in patients with severe aortic stenosis (AS) and reduced LV ejection fraction (EF ≤ 50 %) undergoing transcatheter aortic valve implantation (TAVI).

Methods

A sixty six patients with severe AS and 20 % ≥ LVEF ≤ 50 % who underwent TAVI were included. Patients were categorized into two groups based on LV systolic function recovery 30 days after TAVI defined by ≥ 20 % relative increase in LV Global longitudinal strain (GLS) from baseline. EFT was determined by ECG-gated contrast-enhanced multidetector computed tomography (MDCT).

Results

Forty-five patients (68.0 %) showed LV systolic function recovery. EFT showed no significant correlation with the baseline LV-GLS but was associated with less likelihood of LV systolic function recovery (OR 0.7, 95 % CI 0.50 - 0.98, P = 0.04). In the multivariate analysis, higher LVMI (OR 1.05, 95 % CI 1.00-1.10, P = 0.02), lower LV-GLS (OR 0.55, 95 % CI 0.40-0.82, P = 0.002), and thinner EFT (OR 0.38, 95 % CI 0.20-0.73, P = 0.003) were independently associated with LV systolic function recovery after TAVI.

Conclusion

EFT extent is associated with LV systolic function recovery in AS patients with impaired LVEF undergoing TAVI and therefore may help in risk stratification and management of these patients.

Cold stress, heart failure, and esophageal occlusion cause the death of a West Indian manatee Trichechus manatus in Alabama, USA

Cold stress is the leading cause of mortality in West Indian manatees Trichechus manatus in the northcentral Gulf of Mexico. This report describes an adult male manatee that stranded alive with signs of cold stress in Alabama (USA) waters in January 2022 and died during the rescue intervention. Postmortem examination and histopathologic review revealed multiple contributors to death. While the animal had evidence of cold stress syndrome, there was aortic stenosis and concentric left ventricular hypertrophy as well as an esophageal foreign body (plastic bag). Main findings from blood analysis indicated systemic inflammation and possible disseminated intravascular coagulation. Histopathologic findings from the cardiovascular system included aortic fibromuscular dysplasia, mitral and tricuspid valve endocardiosis, left ventricular myocardial hypertrophy, and right myocardial atrophy. A cause of the cardiovascular findings was not determined. This report is the first to document a case of cold stress syndrome complicated by aortic stenosis and esophageal occlusion in this species.

Early Detection of Left Ventricular Dysfunction With Machine Learning-Based Strain Imaging in Aortic Stenosis Patients

PURPOSE

Aortic stenosis (AS) is a common cardiovascular condition where early detection of left ventricular (LV) dysfunction is essential for timely intervention and optimal management. Current echocardiographic measurements, such as ejection fraction (EF), are insensitive to minor changes in LV function, and strain imaging is typically limited to the global longitudinal strain (GLS) parameter due to robustness issues. This study introduces a novel, fully automatic algorithm to enhance the detection of LV dysfunction in AS patients using multiple strain imaging parameters.

METHODS

We applied supervised machine-learning techniques to classify data from 82 severe AS patients, 96 chest pain subjects, and 319 healthy volunteers.

RESULTS

Our model significantly outperformed EF and GLS in distinguishing AS patients from healthy volunteers (area under the curve [AUC] = 0.97 vs. 0.88 and 0.82, respectively). It also surpassed EF and GLS in differentiating AS patients from chest pain subjects (AUC = 0.95 vs. 0.90 and 0.55, respectively).

CONCLUSION

This novel, clinically interpretable model leverages the potential of strain imaging to enhance diagnostic accuracy and guide clinical decision-making in LV dysfunction, thereby improving clinical practice.

Histopathological myocardial changes in patients with severe aortic stenosis referred for surgical valve replacement: a cardiac magnetic resonance correlation study

AIMS

Myocardial fibrosis (MF) takes part in left ventricular (LV) remodelling in patients with aortic stenosis (AS), driving the transition from hypertrophy to heart failure. The structural changes that occur in this transition are not fully enlightened. The aim of this study was to describe histopathological changes at endomyocardial biopsy (EMB) in patients with severe AS referred to surgical aortic valve replacement (AVR) and to correlate them with LV tissue characterization from pre-operative cardiac magnetic resonance (CMR).

METHODS AND RESULTS

One-hundred fifty-eight patients [73 (68-77) years, 50% women] were referred for surgical AVR because of severe symptomatic AS, with pre-operative CMR (n = 143) with late gadolinium enhancement (LGE), T1, T2 mapping, and extracellular volume fraction (ECV) quantification. Intra-operative septal EMB was obtained in 129 patients. MF was assessed through Masson's Trichrome histochemistry. Immunohistochemistry was performed for both inflammatory cells and extracellular matrix (ECM) characterization (Type I Collagen, Fibronectin, Tenascin C). Non-ischaemic LGE was present in 106 patients (67.1%) [median fraction: 5.0% (2.0-9.7)]. Native T1 was above normal [1053 ms (1024-1071)] and T2 within the normal range [39.3 ms (37.3-42.0)]. Median MF was 11.9% (6.54-19.97), with predominant type I collagen perivascular distribution (95.3%). Sub-endocardial cardiomyocyte ischaemic-like changes were identified in 45% of EMB. There was no inflammation, despite ECM remodelling expression. MF quantification at EMB was correlated with LGE mass (P = 0.008) but not with global ECV (P = 0.125).

CONCLUSION

Patients with severe symptomatic AS referred for surgical AVR have unspecific histological myocardial changes, including signs of cardiomyocyte ischaemic insult. ECM remodelling is ongoing, with MF heterogeneity. These features may be recognized by comprehensive CMR protocols. However, no single CMR parameter captures the burden of MF and histological myocardial changes in this setting.

Assessment of left and right ventricular systolic function in dogs with multicentric lymphoma

OBJECTIVE

Myocardial dysfunction in cardio-oncology is generally thought to be related to the cardiotoxicity of chemotherapy treatment. However, it is known that some tumors have direct effects on myocardial function. These effects have already been studied in man, but there are no publications of these of the effects in dogs. Novel advanced echocardiographic techniques may allow early detection of myocardial dysfunction when compared to conventional echocardiographic techniques. This study aims to assess myocardial systolic function in dogs with multicentric lymphoma prior to initiation of chemotherapy.

ANIMALS

Fifteen dogs with multicentric lymphoma and nineteen healthy dogs.

METHODS

Case-control study. Dogs with multicentric lymphoma and healthy control dogs underwent physical examination, electrocardiography, systolic blood pressure measurement, standard and speckle tracking echocardiography to assess biventricular systolic function.

RESULTS

There were no differences between groups in terms of ejection fraction, fractional shortening, left ventricular systolic and diastolic diameter, tricuspid annular plane systolic excursion, mitral annular plane systolic excursion and fractional area change of the right ventricle (RV). However, there was a reduction in the values of global circumferential strain (p = 0.0003), RV strain (p = 0.01) and RV tissue motion annular displacement (p < 0.05) in the dogs with lymphoma when compared to the control group.

CONCLUSIONS

Speckle tracking techniques appear to demonstrate early systolic dysfunction, primarily affecting the RV, in dogs with lymphoma prior to chemotherapy treatment.

Remodeling in Aortic Stenosis With Reduced and Preserved Ejection Fraction: Insight on Motion Abnormality Via 3D + Time Personalized LV Modeling in Cardiac MRI

BACKGROUND

Increased afterload in aortic stenosis (AS) induces left ventricle (LV) remodeling to preserve a normal ejection fraction. This compensatory response can become maladaptive and manifest with motion abnormality. It is a clinical challenge to identify contractile and relaxation dysfunction during early subclinical stage to prevent irreversible deterioration.

PURPOSE

To evaluate the changes of regional wall dynamics in 3D + time domain as remodeling progresses in AS.

STUDY TYPE

Retrospective.

POPULATION

A total of 31 AS patients with reduced and preserved ejection fraction (14 AS_rEF: 7 male, 66.5 [7.8] years old; 17 AS_pEF: 12 male, 67.0 [6.0] years old) and 15 healthy (6 male, 61.0 [7.0] years old).

FIELD STRENGTH/SEQUENCE

1.5 T Magnetic resonance imaging/steady state free precession and late-gadolinium enhancement sequences.

ASSESSMENT

Individual LV models were reconstructed in 3D + time domain and motion metrics including wall thickening (TI), dyssynchrony index (DI), contraction rate (CR), and relaxation rate (RR) were automatically extracted and associated with the presence of scarring and remodeling.

STATISTICAL TESTS

Shapiro-Wilk: data normality; Kruskal-Wallis: significant difference (P < 0.05); ICC and CV: variability; Mann-Whitney: effect size.

RESULTS

AS_rEF group shows distinct deterioration of cardiac motions compared to AS_pEF and healthy groups (TIAS_rEF : 0.92 [0.85] mm, TIAS_pEF : 5.13 [1.99] mm, TIhealthy : 3.61 [1.09] mm, ES: 0.48-0.83; DIAS_rEF : 17.11 [7.89]%, DIAS_pEF : 6.39 [4.04]%, DIhealthy : 5.71 [1.87]%, ES: 0.32-0.85; CRAS_rEF : 8.69 [6.11] mm/second, CRAS_pEF : 16.48 [6.70] mm/second, CRhealthy : 10.82 [4.57] mm/second, ES: 0.29-0.60; RRAS_rEF : 8.45 [4.84] mm/second; RRAS_pEF : 13.49 [8.56] mm/second, RRhealthy : 9.31 [2.48] mm/second, ES: 0.14-0.43). The difference in the motion metrics between healthy and AS_pEF groups were insignificant (P-value = 0.16-0.72). AS_rEF group was dominated by eccentric hypertrophy (47.1%) with concomitant scarring. Conversely, AS_pEF group was dominated by concentric remodeling and hypertrophy (71.4%), which could demonstrate hyperkinesia with slight wall dyssynchrony than healthy. Dysfunction of LV mechanics corresponded to the presence of myocardial scarring (54.9% in AS), which reverted the compensatory mechanisms initiated and performed by LV remodeling.

DATA CONCLUSION

The proposed 3D + time modeling technique may distinguish regional motion abnormalities between AS_pEF, AS_rEF, and healthy cohorts, aiding clinical diagnosis and monitoring of AS progression. Subclinical myocardial dysfunction is evident in early AS despite of normal EF.

LEVEL OF EVIDENCE

4 TECHNICAL EFFICACY: Stage 1.

Cardiac magnetic resonance patterns of left ventricular remodeling in patients with severe aortic stenosis referred to surgical aortic valve replacement

Left ventricular (LV) hypertrophy is a common finding in patients with severe aortic stenosis (AS). Cardiac magnetic resonance (CMR) is the gold-standard technique to evaluate LV remodeling. Our aim was to assess the prevalence and describe the patterns of LV adaptation in AS patients before and after surgical aortic valve replacement (AVR). Prospective study of 130 consecutive patients (71y [IQR 68-77y], 48% men) with severe AS, referred for surgical AVR. Patterns of LV remodeling were assessed by CMR. Besides normal LV ventricular structure, four other patterns were considered: concentric remodeling, concentric hypertrophy, eccentric hypertrophy, and adverse remodeling. At baseline CMR study: mean LV indexed mass: 81.8 ± 26.7 g/m2; mean end-diastolic LV indexed volume: 85.7 ± 23.1 mL/m2 and median geometric remodeling ratio: 0.96 g/mL [IQR 0.82-1.08 g/mL]. LV hypertrophy occurred in 49% of subjects (concentric 44%; eccentric 5%). Both normal LV structure and concentric remodeling had a prevalence of 25% among the cohort; one patient had an adverse remodeling pattern. Asymmetric LV wall thickening was present in 55% of the patients, with predominant septal involvement. AVR was performed in 119 patients. At 3-6 months after AVR, LV remodeling changed to: normal ventricular geometry in 60%, concentric remodeling in 27%, concentric hypertrophy in 10%, eccentric hypertrophy in 3% and adverse remodeling (one patient). Indexes of AS severity, LV systolic and diastolic function and NT-proBNP were significantly different among the distinct patterns of remodeling. Several distinct patterns of LV remodelling beyond concentric hypertrophy occur in patients with classical severe AS. Asymmetric hypertrophy is a common finding and LV response after AVR is diverse.

Is myocardial fibrosis appropriately assessed by calibrated and 2D strain derived integrated backscatter?

AIMS

Increased collagen content of the myocardium modifies tissue reflectivity and integrated backscatter (IBS) indexes are suggested as markers of myocardial fibrosis (MF). We sought to assess the correlation between calibrated (c) IBS and bidimensional (2D) strain derived IBS with left ventricular (LV) MF in patients with severe aortic stenosis (AS).

METHODS AND RESULTS

We made a prospective observational cohort study including 157 patients with severe AS referred for surgical aortic valve replacement (AVR), with complete preoperative transthoracic echocardiography, cardiac magnetic resonance (CMR) and endomyocardial biopsy (EMB) obtained from the anterior basal septum at the time of surgery. Two groups of 30 patients were specifically evaluated, with and without late gadolinium enhancement (LGE) at CMR. IBS was obtained at QRS peak from both parasternal long axis (PLAX) and apical-three-chamber (AP3C) views and measured in decibels (dB). Whole-cardiac cycle IBS at basal anterior septum was obtained from 2D longitudinal strain. Correlation analysis of reflectivity indexes was performed with global and segmental (anterior basal septum) values of native T1 and extracellular volume (ECV), and EMB collagen volume fraction (CVF) (Masson´s Trichrome). IBS values were compared in both group of patients (LGE + vs. LGE -). 60 patients (74 [36-74] years, 45% male) with high gradient (mean gradient: 63 ± 20mmHg), normal flow (45 ± 10mL/m2) AS and preserved left ventricular ejection fraction (60 ± 9%) were included. Basal septum cIBS was - 17.45 (-31.2-10.95) and - 9.17 ± 9.45dB from PLAX and A3C views, respectively. No significant correlations were found between IBS and both non-invasive CMR tissue characterization and CVF: median MF of 9.7(2.1-79.9)%. Acoustic indexes were not significantly different according to the presence of pre-operative LGE.

CONCLUSION

In this group of patients with classical severe AS, IBS reflectivity indexes are of no added value to discriminate the presence of MF.

Left ventricular mass regression after aortic valve replacement with the TTK Chitra™ monoleaflet tilting disc valve

Objective

To study the extent of left ventricular (LV) mass regression in aortic stenosis after aortic valve replacement with the TTK Chitra™ tilting disc valve.

Methods and materials

This study included patients with severe isolated aortic stenosis (AS), admitted in our department. They had aortic valve replacement (AVR) with the TTK Chitra™ tilting disc valve, between January 2008 and December 2010. Data were collected from consecutive forty-eight patients. LV mass and diametric and functional parameters were recorded preoperatively and compared with echocardiography after 3 months, 6 months, then yearly, up to 3 years.

Results

70.8% of the patients were males and 29.2% were females. The mean duration of illness was 37.92 ± 25.87 months. The mean LV ejection fraction increased 3 months after surgery (61.56 ± 10.10% to 69.31 ± 9.34%) with a sustained increase for the next 3 years. The mean LV end-diastolic diameter decreased (50.16 ± 6.05 mm to 45.69 ± 5.93 mm) after 3 months of surgery, with a sustained decrease for the next 3 years. The mean LV end-systolic diameter decreased (32.84 ± 6.96 mm to 29.41 ± 5.86 mm) after 3 months of surgery and then showed a sustained decrease for the next 3 years. The LV mass assessed with echocardiography regressed from 324.65 ± 97.77 g before surgery to 252.64 ± 71.12 g after 3 months and then showed a sustained decrease over the next 3 years.

Conclusion

Significant LV mass regression occurred after AVR with the TTK Chitra™ valve. The maximum reversal was found to be within the first 3 months after surgery with sustained beneficial improvement for the next 3 years.

Aortic Valve Calcium in Relation to Subclinical Cardiac Dysfunction and Risk of Heart Failure

BACKGROUND

The link between (mild) aortic valve calcium (AVC) with subclinical cardiac dysfunction and with risk of heart failure (HF) remains unclear. This research aims to determine the association of computed tomography-assessed AVC with echocardiographic measurements of cardiac dysfunction, and with HF in the general population.

METHODS

We included 2348 participants of the Rotterdam Study cohort (mean age 68.5 years, 52% women), who had AVC measurement between 2003 and 2006, and without history of HF at baseline. Linear regression models were used to explore relationship between AVC and echocardiographic measures at baseline. Participants were followed until December 2016. Fine and Gray subdistribution hazard models were used to assess the association of AVC with incident HF, accounting for death as a competing risk.

RESULTS

The presence of AVC or greater AVC were associated with larger mean left ventricular mass and larger mean left atrial size. In particular, AVC ≥800 showed a strong association (body surface area indexed left ventricular mass, β coefficient: 22.01; left atrium diameter, β coefficient: 0.17). During a median of 9.8 years follow-up, 182 incident HF cases were identified. After accounting for death events and adjusting for cardiovascular risk factors, one-unit larger log (AVC+1) was associated with a 10% increase in the subdistribution hazard of HF (subdistribution hazard ratio, 1.10 [95% CI, 1.03-1.18]), but the presence of AVC was not significantly associated with HF risk in fully adjusted models. Compared with the AVC=0, AVC between 300 and 799 (subdistribution hazard ratio, 2.36 [95% CI, 1.32-4.19]) and AVC ≥800 (subdistribution hazard ratio, 2.54 [95% CI, 1.31-4.90]) were associated with a high risk of HF.

CONCLUSIONS

Presence and high levels of AVC were associated with markers of left ventricular structure, independent of traditional cardiovascular risk factors. Larger computed tomography-assessed AVC is an indicative of increased risk for the development of HF.

Radiomic analysis of enhanced CMR cine images predicts left ventricular remodeling after TAVR in patients with symptomatic severe aortic stenosis

Objective

This study aimed to develop enhanced cine image-based radiomic models for non-invasive prediction of left ventricular adverse remodeling following transcatheter aortic valve replacement (TAVR) in symptomatic severe aortic stenosis.

Methods

A total of 69 patients (male:female = 37:32, median age: 66 years, range: 47-83 years) were retrospectively recruited, and severe aortic stenosis was confirmed via transthoracic echocardiography detection. The enhanced cine images and clinical variables were collected, and three types of regions of interest (ROIs) containing the left ventricular (LV) myocardium from the short-axis view at the basal, middle, and apical LV levels were manually labeled, respectively. The radiomic features were extracted and further selected by using the least absolute shrinkage and selection operator (LASSO) regression analysis. Clinical variables were also selected through univariate regression analysis. The predictive models using logistic regression classifier were developed and validated through leave-one-out cross-validation. The model performance was evaluated with respect to discrimination, calibration, and clinical usefulness.

Results

Five basal levels, seven middle levels, eight apical level radiomic features, and three clinical factors were finally selected for model development. The radiomic models using features from basal level (Rad I), middle level (Rad II), and apical level (Rad III) had achieved areas under the curve (AUCs) of 0.761, 0.909, and 0.913 in the training dataset and 0.718, 0.836, and 0.845 in the validation dataset, respectively. The performance of these radiomic models was improved after integrating clinical factors, with AUCs of the Combined I, Combined II, and Combined III models increasing to 0.906, 0.956, and 0.959 in the training dataset and 0.784, 0.873, and 0.891 in the validation dataset, respectively. All models showed good calibration, and the decision curve analysis indicated that the Combined III model had a higher net benefit than other models across the majority of threshold probabilities.

Conclusion

Radiomic models and combined models at the mid and apical slices showed outstanding and comparable predictive effectiveness of adverse remodeling for patients with symptomatic severe aortic stenosis after TAVR, and both models were significantly better than the models of basal slice. The cardiac magnetic resonance radiomic analysis might serve as an effective tool for accurately predicting left ventricular adverse remodeling following TAVR in patients with symptomatic severe aortic stenosis.

Arterial stiffness in aortic stenosis - complex clinical and prognostic implications

Arterial stiffness and degenerative aortic stenosis (AoS) are frequently associated leading to a combined valvular and vascular load imposed on the left ventricle (LV). Vascular load consists of a pulsatile load represented by arterial stiffness and a steady load corresponding to vascular resistance. Increased vascular load in AoS has been associated with LV dysfunction and poor prognosis in pre-intervention state, as well as after aortic valve replacement (AVR), suggesting that the evaluation of arterial load in AoS may have clinical benefits. Nevertheless, studies that investigated arterial stiffness in AoS either before or after AVR used various methods of measurement and their results are conflicting. The aim of the present review was to summarize the main pathophysiological mechanisms which may explain the complex valvulo-arterial interplay in AoS and their consequences on LV structure and function on the patients' outcome. Future larger studies are needed to clarify the complex hemodynamic modifications produced by increased vascular load in AoS and its changes after AVR. Prospective evaluation is needed to confirm the prognostic value of arterial stiffness in patients with AoS. Simple, non-invasive, reliable methods which must be validated in AoS still remain to be established before implementing arterial stiffness measurement in patients with AoS in clinical practice.

A systematic review of micro-RNAs in aortic stenosis and cardiac fibrosis

Aortic stenosis (AS) is the commonest valve lesion requiring surgery in the Western world. The presence of myocardial fibrosis is associated with mortality even after valve replacement. MicroRNAs could serve as biomarkers of fibrosis and risk stratify patients for earlier intervention. This study aimed to systematically review reports of micro-RNA (miR) associated with fibrosis in AS and identify potential biomarkers. We searched EMBASE, Medline, and Web of Science up to May 2020. Studies that reported on the role of miRs in AS and cardiac fibrosis were included. Study quality was assessed using the Newcastle-Ottawa scale. Of 4230 reports screened, 25 were included. All studies were of low to moderate quality. MiRs were analyzed in myocardial tissue (n = 10), aortic valve tissue (n = 5), plasma (n = 5), and serum (n = 5). A total of 365 miRs were reported, of which only a few were reported in more than one paper (3 in the myocardium, 5 in the aortic valve, and 1 in plasma). miR-21 was upregulated in plasma and myocardial tissue. MiR-19b was downregulated in the myocardium. Papers reporting myocardial miR-1 contradicted each other, and miR-133a was associated with increased left ventricular mass regression post-surgery. In the aortic valve, miRs-665, 602 and 939 were downregulated, and miRs-193b and 214 were upregulated. The data on miR in fibrosis in AS is scarce and of low to moderate quality. Further studies are needed to identify novel miRs as biomarkers, especially at an earlier asymptomatic phase of the disease.

Data Mining Identifies CCN2 and THBS1 as Biomarker Candidates for Cardiac Hypertrophy

Cardiac hypertrophy is a condition that may contribute to the development of heart failure. In this study, we compare the gene-expression patterns of our in vitro stem-cell-based cardiac hypertrophy model with the gene expression of biopsies collected from hypertrophic human hearts. Twenty-five differentially expressed genes (DEGs) from both groups were identified and the expression of selected corresponding secreted proteins were validated using ELISA and Western blot. Several biomarkers, including CCN2, THBS1, NPPA, and NPPB, were identified, which showed significant overexpressions in the hypertrophic samples in both the cardiac biopsies and in the endothelin-1-treated cells, both at gene and protein levels. The protein-interaction network analysis revealed CCN2 as a central node among the 25 overlapping DEGs, suggesting that this gene might play an important role in the development of cardiac hypertrophy. GO-enrichment analysis of the 25 DEGs revealed many biological processes associated with cardiac function and the development of cardiac hypertrophy. In conclusion, we identified important similarities between ET-1-stimulated human-stem-cell-derived cardiomyocytes and human hypertrophic cardiac tissue. Novel putative cardiac hypertrophy biomarkers were identified and validated on the protein level, lending support for further investigations to assess their potential for future clinical applications.

Evaluation of left ventricular diastolic function in patients operated for aortic stenosis

Background

Left ventricular diastolic dysfunction is common in patients with aortic valve stenosis (AS) and reportedly affects prognosis after surgical aortic valve replacement (SAVR). Here we investigated whether and how diastolic function (assessed following the most recent guidelines) was affected by SAVR, and whether preoperative diastolic function affected postoperative outcome. We also examined whether long-term mortality was associated with preoperative NT-proBNP and postoperative heart failure (PHF).

Methods

We performed a prospective observational study of 273 patients with AS who underwent AVR with or without concomitant coronary artery bypass surgery. Of these patients, 247 were eligible for assessment of left ventricular (LV) filling pressure. Preoperatively and at the 6-month postoperative follow-up, we measured N-terminal pro-B type natriuretic peptide (NT-proBNP) in serum and assessed diastolic function with Doppler echocardiography. PHF was diagnosed using prespecified criteria. Multivariable logistic regression was performed to explore variables associated with high LV filling pressure. Cox regression was performed to explore variables associated with mortality, accounting for timeto-event.

Results

At the time of surgery, 22% (n = 54) of patients had diastolic dysfunction expressed as high LV filling pressure. Of these 54 patients, 27 (50%) showed postoperative diastolic function improvement. Among the 193 patients with preoperative low LV filling pressure, 24 (12%) showed postoperative diastolic function deterioration. Increased long-term mortality was associated with PHF and high preoperative NT-proBNP, but not with preoperative or postoperative diastolic dysfunction. Cox regression revealed the following independent risk factors for long-term mortality: diabetes, renal dysfunction, preoperative NT-proBNP>960 ng/L, age, and male gender.

Conclusions

Surgery for aortic stenosis improved diastolic function in patients with high LV filling pressure in 50% of the patients. Our results could not confirm the previously suggested role of diastolic dysfunction as a marker for poor long-term survival after SAVR. Our findings showed that both PHF and high preoperative NT-proBNP were associated with long-term mortality.

Echocardiographic assessment of diastolic dysfunction in elderly patients with severe aortic stenosis before and after aortic valve replacement

Background

The 2016 guidelines of the American Society of Echocardiography (ASE) and European Association of Cardiovascular Imaging (EACVI) for evaluation of left ventricular (LV) diastolic dysfunction by Doppler flow and tissue Doppler- echocardiography do not adjust assessment of high filling pressures for patients with aortic stenosis (AS). However, most of the studies on this patient group indicate age independent specific diastolic features in AS. The aim of this study is to identify disease-specific range and distribution of diastolic functional parameters and their ability to identify high N-terminal prohormone of brain natriuretic peptide (NT-proBNP) levels as a marker for high filling pressures.

Methods

In this study, 169 patients who underwent surgical aortic valve replacement (SAVR) or transcatheter aortic valve replacement (TAVR) were prospectively enrolled. Resting echocardiography was performed including Doppler of the mitral inflow, pulmonary venous flow, tricuspid regurgitant flow and tissue Doppler in the mitral ring and indexed volume-estimates of the left atrium (LAVI). Echocardiography, and NT-proBNP levels were assessed before TAVR/SAVR and at two postoperative visits at 6 and 12 months.

Results

Pre- and postoperative values were septal e′; 5.1 ± 3.9, 5.2 ± 1.6 cm/s; lateral e′ 6.3 ± 2.1; 7.7 ± 2.7 cm/s; E/e′19 ± 8; 16 ± 7 cm/s; E velocity 96 ± 32; 95 ± 32 cm/s; LAVI 39 ± 8; 36 ± 8 ml/m², pulmonary artery pressure (PAP) 39 ± 8; 36 ± 8 mmHg, respectively. The scoring recommended by ASE/EACVI detected elevated NT pro-BNP with a specificity of 25%. Adjusting thresholds towards PAP ≥ 40 mmHg, E velocity ≥ 100 cm/s, E deceleration time < 220 ms, and E/septal e′ ≥ 20 or septal e′ < 5.0 cm/s increased prediction of NT-proBNP levels ≥500 ng/L with substantially improved specificity (> 85%).

Conclusion

Diastolic echocardiographic parameters in AS indicate persistent impaired relaxation and NT-proBNP indicate elevated filling pressures in most of the patients, improving only modestly 6–12 months after TAVR and SAVR. Applying the 2016 ASE/EACVI recommendations for detection of elevated filling pressures to patients with AS, elevated NT pro-BNP levels could not be reliably detected. However, adjusting thresholds of the echocardiographic parameters increased specificities to useful diagnostic levels.

Trial registration

The study was prospectively approved by the regional ethical committee, REK North with the registration number: REK 2010/397-10.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12947-021-00262-1.

Prevalence and prognostic impact of apical sparing contractility pattern in patients with aortic stenosis referred for transcatheter aortic valve implantation

INTRODUCTION

Prolonged afterload increase in aortic stenosis (AS) may alter left ventricular (LV) contractility, irrespective of LV ejection fraction (LVEF). The prevalence and morbimortality associated with the apical sparing strain pattern (ASP), a typical finding of cardiac amyloidosis (CA), are not fully understood in patients with AS. We assessed the prevalence of the ASP in patients with severe AS and its clinical impact after transcatheter aortic valve implantation (TAVI).

METHODS

Eighty-nine consecutive patients with severe AS and LV hypertrophy referred for TAVI were included. Baseline clinical and echocardiographic data were assessed, including the ASP in bull's eye plots (ASPB), relative apical longitudinal strain (RALS) and EF to global longitudinal strain (EF/GLS) ratio. We analysed all-cause mortality; a composite of all-cause mortality, stroke, and heart failure hospitalizations; and the rate of pacemaker implantation, after TAVI.

RESULTS

Mean age was 82 ± 6 years and mean LVEF was 57 ± 10%. ASPB and RALS >1 were present in 43.8% and 24.7% of patients, respectively. Over a median follow-up of 13 months (IQR 6-32), ASPB was associated with higher rates of all-cause mortality (log-rank P=0.001) and was an independent predictor of all-cause mortality in multivariate analysis. Combination of the ASPB and GLS or EF/GLS ratio improved the risk stratification. Patients with RALS >1 were more likely to have new BBB and an indication for pacemaker implantation (P=0.048).

CONCLUSION

The ASP, as assessed by the ASPB and RALS, was frequent in patients with AS regardless of the diagnosis of CA. The ASPB may refine risk stratification in patients referred for TAVI.

Changes of Right Ventricular Function After Transcatheter Aortic Valve Replacement and Association With Outcomes

BACKGROUND

Baseline right ventricular (RV) dysfunction represents a predictor for poor outcome in patients undergoing transcatheter aortic valve replacement (TAVR). However, RV function may improve after TAVR, which could have important implications on outcomes. The aim of the present study was to assess changes in RV function after TAVR and its prognostic value regarding clinical outcome.

METHODS AND RESULTS

Patients undergoing TAVR at our institution were consecutively enrolled and categorized into 4 groups according to changes in RV function during echocardiographic follow-up at 6 months. A total of 188 patients were included. Of those showing normal function at baseline, 87% (130/149) had preserved RV function at follow-up (group 1), whereas 13% (19/149) developed new RV dysfunction (group 2). Of those with RV dysfunction at baseline (39 patients), RV function normalized in 46% (18/39) (group 3) and remained impaired in 54% (21/39) (group 4). The Kaplan-Meier estimated survival at 3 years was highest in patients in group 1 (83%), intermediate in group 2 (65%) and 3 (69%), whereas group 4 had the worst survival (37%; P < .001). Furthermore, new or persistent RV dysfunction was identified to be independently associated with mortality during follow-up (hazard ratio 2.55; interquartile range 1.03-6.47, P = .004).

CONCLUSIONS

Patients with preserved RV function have a high 3-year survival. Normalization of RV function showed improved survival compared with patients with persistent RV dysfunction, who had a dismal prognosis despite TAVR.

Single-Dose Del Nido Cardioplegia vs. Blood Cardioplegia in Aortic Valve Replacement Surgery

INTRODUCTION

In this study, we aimed to compare Del Nido cardioplegia (DNC) with blood cardioplegia (BC) in aortic valve replacement.

METHODS

A two-year single-institute retrospective cohort study was accomplished. Subjects who underwent aortic valve replacement surgery were divided into two groups (DNC and BC) and outcomes were compared.

RESULTS

Preoperative demographics and clinical data of the patients in both groups were similar. The time until cardiac arrest following administration of the first dose of cardioplegia was statistically significantly shorter in the BC group (47.0 sec. 25-103) than in the DNC group (63.0 sec. 48-140) (P=0.012). Cross-clamping time was longer in the BC group (48.7±12.3 min. vs. 41.5±11.8 min.) (P=0.041). Cardiopulmonary bypass time was statistically significantly shorter in the DNC group (BC 60.8±18.5 min., DNC 53.7±15.2 min.) (P=0.046). The rate of postoperative use of intravenous positive inotropic support drugs (dopamine, dobutamine, norepinephrine, etc.) for more than two hours was significantly higher in the BC group (20 [23.5%] in the BC group and nine [17.3%] in the DNC group) (P=0.035). Creatine kinase myocardial band and troponin I levels were slightly lower in patients receiving DNC, but no statistically significant difference was detected.

CONCLUSION

Del Nido cardioplegia is safe and can be used efficiently as an alternative to blood cardioplegia in isolated aortic valve replacement surgery.

Left Ventricular Remodeling in Degenerative Aortic Valve Stenosis

Aortic stenosis was once considered a pure isolated valve obstacle challenging left ventricle driving force of contraction and flow generation. Left ventricular (LV) adaptation was merely interpreted as a uniform hypertrophic response to increased afterload. However, in these last 2 decades cardiac imaging research and some histopathology correlation studies brought insight towards the complex interaction between the vasculature, the valve and the myocardium. Verily, LV remodeling in this setting is a complex multidetermined process that goes further beyond myocardial hypertrophy. Ultrastructural changes involving both diffuse and replacement fibrosis of the myocardium take part and might explain the transition of clinical phenotypes with distinct prognosis, from compensated hypertrophy to LV maladaptive dysfunction and heart failure. Presently, the combined appropriate use of echocardiography and cardiac magnetic resonance may better assess the global LV afterload, hypertrophy and geometric remodeling, global and regional LV function, beyond ejection fraction, and structural changes that include the fibrotic burden of the myocardium. As a whole these may not only better stratify individual risk of disease progression but also identify patients benefiting from earlier valve intervention. In this paper, we review the maladaptive response of the LV to chronic pressure overload, describing the different signaling pathways and mechanisms that underly both hypertrophy and remodeling. Histomorphology changes in this setting are described and we try to make sense of the use of new imaging tools for LV characterization.

C-C chemokine receptor 5 signaling contributes to cardiac remodeling and dysfunction under pressure overload

Aortic stenosis (AS) leads to chronic pressure overload, cardiac remodeling and eventually heart failure. Chemokines and their receptors have been implicated in pressure overload‑induced cardiac remodeling and dysfunction. In the present study, the role of C‑C chemokine receptor 5 (CCR5) in pressure overload‑induced cardiac remodeling and dysfunction was investigated in mice subjected to transverse aortic constriction (TAC). Cardiac levels of CCR5 and C‑C motif chemokine ligands (CCLs)3, 4 and 5 were determined by western blotting and reverse transcription‑quantitative PCR, respectively. Cardiac functional parameters were evaluated by echocardiographic and hemodynamic measurements. Myocardial fibrosis was assessed by Masson's trichrome staining and α‑smooth muscle actin immunostaining. Myocardial hypertrophy and inflammatory cell infiltration were evaluated by hematoxylin and eosin staining. Angiotensin II (Ang II)‑induced hypertrophy of H9c2 cardiomyocytes was assessed by F‑actin immunostaining. ERK1/2 and P38 phosphorylation was examined by western blotting. TAC mice exhibited higher myocardial CCL3, CCL4, CCL5 and CCR5 levels compared with sham mice. Compared with sham mice, TAC mice also exhibited impaired cardiac function along with myocardial hypertrophy, fibrosis and inflammatory cell infiltration. TAC‑induced cardiac remodeling and dysfunction were effectively ameliorated by administration of anti‑CCR5 but not by IgG control antibody. Mechanistically, increased ERK1/2 and P38 phosphorylation was detected in TAC hearts and Ang II‑stimulated H9c2 cardiomyocytes. Treatment with anti‑CCR5 antibody decreased ERK1/2 and P38 phosphorylation and attenuated Ang II‑induced H9c2 cell hypertrophy. CCR5 inhibition protected against pressure overload‑induced cardiac abnormality. The findings of the present study indicate that ERK1/2 and P38 signaling pathways may be involved in the cardioprotective effects of CCR5 inhibition.

Antihypertensive therapies in moderate or severe aortic stenosis: a systematic review and meta-analysis

BACKGROUND

Hypertension confers a poor prognosis in moderate or severe aortic stenosis (AS), however, antihypertensive therapy (AHT) is often not prescribed due to the perceived deleterious effects of vasodilation and negative inotropes.

OBJECTIVE

To assess the efficacy and safety outcomes of AHT in adults with moderate or severe AS.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

The Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE and grey literature were searched without language restrictions up to 9 September 2019.

STUDY ELIGIBILITY CRITERIA, APPRAISAL AND SYNTHESIS METHODS

Two independent reviewers performed screening, data extraction and risk of bias assessments from a systematic search of observational studies and randomised controlled trials comparing AHT with a placebo or no AHT in adults with moderate or severe AS for any parameter of efficacy and safety outcomes. Conflicts were resolved by the third reviewer. Meta-analysis with pooled effect sizes using random-effects model, were estimated in R.

MAIN OUTCOME MEASURES

Mortality, Left Ventricular (LV) Mass Index, systolic blood pressure, diastolic blood pressure and LV ejection fraction RESULTS: From 3025 publications, 31 studies (26 500 patients) were included in the qualitative synthesis and 24 studies in the meta-analysis. AHT was not associated with mortality when all studies were pooled, but heterogeneity was substantial across studies. The effect size of AHT differed according to drug class. Renin-angiotensin-aldosterone system inhibitors (RAASi) were associated with reduced risk of mortality (Pooled HR 0.58, 95% CI 0.43 to 0.80, p=0.006), The differences in changes of haemodynamic or echocardiographic parameters from baseline with and without AHT did not reach statistical significance.

CONCLUSION

AHT appears safe, is well tolerated. RAASi were associated with clinical benefit in patients with moderate or severe AS.

Assessment of Left Ventricular Myocardial Diseases with Cardiac Computed Tomography

Rapid advances in cardiac computed tomography (CT) have enabled the characterization of left ventricular (LV) myocardial diseases based on LV anatomical morphology, function, density, and enhancement pattern. Global LV function and regional wall motion can be evaluated using multi-phasic cine CT images. CT myocardial perfusion imaging facilitates the identification of hemodynamically significant coronary artery disease. CT delayed-enhancement imaging is used to detect myocardial scar in myocardial infarction and to measure the extracellular volume fraction in non-ischemic cardiomyopathy. Multi-energy cardiac CT allows the mapping of iodine distribution in the myocardium. This review summarizes the current techniques of cardiac CT for LV myocardial assessment, highlights the key findings in various myocardial diseases, and presents future applications to complement echocardiography and cardiovascular magnetic resonance.

Mechanisms underlying the cross-talk between heart and cancer

Cardiovascular diseases and cancer remain the leading cause of death worldwide. Despite the fact that these two conditions have long been considered as distinct clinical entities, recent epidemiological and experimental studies suggest that they should be contemplated and treated as co-morbidities. Heart failure represents nowadays a well-established complication of cancer, primarily as a consequence of the aggressive use of cardiotoxic anti-cancer treatments. On the other hand, the provocative idea that heart failure can prime carcinogenesis has started to emerge, though the molecular basis is still to be fully elucidated. This review summarizes the current knowledge on the mechanisms underlying the bidirectional communication between the failing heart and the cancer. We will discuss and/or speculate on the role of molecular mediators released by either the tumour or the heart that can potentially link heart failure and cancer.

Multiscale simulation of the effects of atrioventricular block and valve diseases on heart performance

A new mathematical model of the cardiovascular system is proposed. The left ventricle is described by an axisymmetric multiscale model where myocardium is treated as an incompressible transversely isotropic medium with a realistic distribution of fibre orientation. Active tension and its regulation by Ca²⁺ ions are described by our recent kinetic model. A lumped parameter model is used for the simulation of blood circulation, in which the left and right atria and the right ventricle are described by a system of ordinary differential equations for active pressure-volume relationships. The stress and strain of the left ventricle myocardium were calculated by the finite element method implemented by the authors. The changes in the haemodynamics upon changes in preload of a healthy heart, upon physical exercise, and in case of atrioventricular block with different types of arrhythmias were simulated. To simulate the effect of stenosis or regurgitation of the aortic or mitral valves, the hydraulic and inertial flow resistances of the heart valves were set as functions of their orifice areas. The model reproduced a number of phenomena observed in clinical practice, including the classification of the severity of valve disease.

Cardiac remodeling in aortic and mitral valve disease: a simulation study with clinical validation

Remodeling is an important long-term determinant of cardiac function throughout the progression of heart disease. Numerous biomolecular pathways for mechanosensing and transduction are involved. However, we hypothesize that biomechanical factors alone can explain changes in myocardial volume and chamber size in valve disease. A validated model of the human vasculature and the four cardiac chambers was used to simulate aortic stenosis, mitral regurgitation, and aortic regurgitation. Remodeling was simulated with adaptive feedback preserving myocardial fiber stress and wall shear stress in all four cardiac chambers. Briefly, the model used myocardial fiber stress to determine wall thickness and cardiac chamber wall shear stress to determine chamber volume. Aortic stenosis resulted in the development of concentric left ventricular hypertrophy. Aortic and mitral regurgitation resulted in eccentric remodeling and eccentric hypertrophy, with more pronounced hypertrophy for aortic regurgitation. Comparisons with published clinical data showed the same direction and similar magnitudes of changes in end-diastolic volume index and left ventricular diameters. Changes in myocardial wall volume and wall thickness were within a realistic range in both stenotic and regurgitant valvular disease. Simulations of remodeling in left-sided valvular disease support, in both a qualitative and quantitative manner, that left ventricular chamber size and hypertrophy are primarily determined by preservation of wall shear stress and myocardial fiber stress. NEW & NOTEWORTHY Cardiovascular simulations with adaptive feedback that normalizes wall shear stress and fiber stress in the cardiac chambers could predict, in a quantitative and qualitative manner, remodeling patterns seen in patients with left-sided valvular disease. This highlights how mechanical stress remains a fundamental aspect of cardiac remodeling. This in silico study validated with clinical data paves the way for future patient-specific predictions of remodeling in valvular disease.

Role of Cardiac Computed Tomography in the Diagnosis of Left Ventricular Myocardial Diseases

Multimodality imaging is indicated for the evaluation of left ventricular (LV) myocardial diseases. Cardiac magnetic resonance (CMR) allows morphological and functional assessment of the LV along with soft tissue characterization. Technological advances in cardiac computed tomography (CT) have led to the development of techniques for diagnostic acquisition in LV myocardial disease. Cardiac CT facilitates the characterization of LV myocardial disease based on anatomy, function, and enhancement pattern. LV regional and global functional parameters are evaluated using multi-phasic cine CT images. CT myocardial perfusion facilitates the identification of hemodynamically significant coronary artery stenosis. Cardiac CT with delayed enhancement is used to detect myocardial scarring or fibrosis in myocardial infarction and non-ischemic cardiomyopathy, and for the measurement of extracellular volume fraction in non-ischemic cardiomyopathy. In this review, we review imaging techniques and key imaging features of cardiac CT used for the evaluation of myocardial diseases, along with CMR findings.

Clinical aspects of myocardial fibrosis in adults with Ebstein's anomaly

Heart failure and arrhythmia are common complications in adults with Ebstein's anomaly. They may result not only from hemodynamic alterations, but also from myocardial fibrosis. Late gadolinium enhancement (LGE) by CMR enables the evaluation of myocardial fibrosis. The aim of the study was to asses the presence of LGE and its relation to clinical outcome. We studied a group of 37 unoperated adults aged 43.0 ± 14.4 years with Ebstein's anomaly from the congenital heart disease outpatient clinic. Study protocol included: cardiopulmonary test, assessment of supraventricular arrhythmia (SVA), and CMR with evaluation of cardiac chambers' morphology and function, and presence of LGE. Variables following normal distribution were shown as mean ± SD if otherwise median (range) was applied. Fibrosis was found in 18 patients (48.6%) and was distributed as follows: 12 patients (32.4%) in the right atrium, 12 (32.4%) in the atrialized right ventricle, and 2 (5.4%) in the functional right ventricle. In patients with fibrosis, the tricuspid regurgitation fraction was bigger (48.3 ± 19.7 vs. 36.1 ± 22.6%, p = 0.048) and SVA was more frequent [12 (66.7%) vs. 6 (31.6%), p = 0.046] when compared to patients without fibrosis. However, exercise capacity did not differ between patients with and without LGE (peak VO2 24.0 ± 4.7 vs. 23.7 ± 4.4, p = 0.87). In adults with Ebstein's anomaly fibrosis estimated by LGE-CMR was localized in the right atrium and the right ventricle only. Volume overload resulting from tricuspid regurgitation might be a factor conducive to fibrosis. Myocardial fibrosis did not influence exercise capacity. Association between myocardial fibrosis and supraventricular arrhythmia was confirmed.

Predictors of Mortality and Symptomatic Outcome of Patients With Low-Flow Severe Aortic Stenosis Undergoing Transcatheter Aortic Valve Replacement

Background

Impaired left ventricular (LV) ejection fraction is a common finding in patients with aortic stenosis and serves as a predictor of morbidity and mortality after transcatheter aortic valve replacement. However, conflicting data on the most accurate measure for LV function exist. We wanted to examine the impact of LV ejection fraction, mean pressure gradient, and stroke volume index on the outcome of patients treated by transcatheter aortic valve replacement.

Methods and Results

Patients treated by transcatheter aortic valve replacement were primarily separated into normal flow (NF; stroke volume index >35 mL/m²) and low flow (LF; stroke volume index ≤35 mL/m²). Afterwards, patients were divided into 5 groups: “NF–high gradient,” “NF–low gradient” (NF‐LG), “LF–high gradient,” “paradoxical LF‐LG,” and “classic LF‐LG.” The 3‐year mortality was the primary end point. Of 1600 patients, 789 (49.3%) were diagnosed as having LF, which was characterized by a higher 30‐day (P=0.041) and 3‐year (P<0.001) mortality. LF was an independent predictor of all‐cause (hazard ratio, 1.29; 95% confidence interval, 1.03–1.62; P=0.03) and cardiovascular (hazard ratio, 1.37; 95% confidence interval, 1.06–1.77; P=0.016) mortality. Neither mean pressure gradient nor LV ejection fraction was an independent predictor of mortality. Patients with paradoxical LF‐LG (35.0%), classic LF‐LG (35.1%) and LF–high gradient (38.1%) had higher all‐cause mortality at 3 years compared with NF–high gradient (24.8%) and NF‐LG (27.9%) (P=0.001). However, surviving patients showed a similar improvement in symptoms regardless of aortic stenosis entity.

Conclusions

LF is a common finding within the aortic stenosis population and, in contrast to LV ejection fraction or mean pressure gradient, an independent predictor of all‐cause and cardiovascular mortality. Despite increased long‐term mortality, high procedural success and excellent functional improvement support transcatheter aortic valve replacement in patients with LF severe aortic stenosis.

Longitudinal strain assessed by cardiac magnetic resonance correlates to hemodynamic findings in patients with severe aortic stenosis and predicts positive remodeling after transcatheter aortic valve replacement

AIMS

To assess left-ventricular strain parameters before and after transcatheter aortic valve replacement (TAVR) by feature tracking cardiac magnetic resonance imaging (FT CMR) and to correlate the findings to hemodynamic state and left-ventricular remodeling.

METHODS AND RESULTS

Patients with symptomatic AS underwent FT CMR before and after TAVR. Patients were carefully evaluated by a comprehensive work-up including CMR, echocardiography and left and right heart catheterization. Thirty patients formed the study population. High-flow/high-gradient (HF/HG) aortic stenosis was diagnosed in 11 patients (36.7%), 6 patients (20.0%) exhibited low-flow/low-gradient AS (LF/LG) and 13 patients (43.3%) were classified to have so-called paradoxical low-flow/low-gradient (PLF/LG) AS. The HF/HG patients had a significantly reduced longitudinal strain which recovered after TAVR (-12.67 ± 4.60 to -15.46 ± 5.61%, p = 0.048). In the LF/LG group, an even more pronounced reduction of longitudinal strain and also an impairment of longitudinal velocity could be observed. Both parameters improved after therapy (strain: -5.06 ± 4.25 to -8.02 ± 3.28%, p = 0.045; velocity: 25.33 ± 9.63 to 37.13 ± 11.64 mm/s, p = 0.042). Patients with PLF/LG showed preserved longitudinal strain but a reduction of longitudinal velocity similar to the LF/LG group. These patients did not show a significant improvement of strain parameters after TAVR. Longitudinal velocity exhibited the highest predictive power for the identification of a low-flow state (sensitivity 75%, specificity 80%).

CONCLUSION

Improvement of longitudinal strain parameters after TAVR is dependent on the initial hemodynamically defined AS subgroup.

Early Recovery of Left Ventricular Systolic Function after Transcatheter Aortic Valve Implantation

Background

A lot of studies have shown a positive effect of transcatheter aortic valve implantation (TAVI) on left ventricular ejection fraction (LVEF).

Objectives

We aimed to investigate the effect of TAVI on left ventricular function and correlate this phenomenon with hypertrophy degree in an early follow-up.

Materials and Methods

Between August 2015 and July 2016, 250 consecutive patients with symptomatic severe aortic stenosis (AS) underwent TAVI in our institution. Given the aim of this analysis, only patients with an LVEF <50%, no more than moderate mitral valve regurgitation, successful valve implantation, and 1-month follow-up available were included in the study (n = 46). Patients were enrolled in a prospective database, with clinical and echocardiographic evaluations at 1 month after TAVI.

Results

All patients had severe symptomatic AS (mean transaortic pressure gradients: 44.1 ± 13.8 mmHg and mean aortic valve area: 0.66 ± 0.19 cm²). Mean baseline LVEF was 39.3 ± 8.8%. Significant hemodynamic improvement was observed after TAVI. Mean transvalvular aortic gradient decreased significantly from 44.1 ± 13.8 mmHg to 8.9 ± 4.2 mmHg (P < 0.005). A statistically significant improvement in LVEF compared to baseline was observed in the 1^st month of follow-up (39.3 ± 8.8% vs. 44.1 ± 10.1%, P < 0.019). Overall, 52.2% of patients showed an increase in LVEF, 32.6% had no change, while only 2.2% had a decrease in LVEF. Interestingly, we found a significant reverse correlation between LVEF improvement and ventricular hypertrophy measured as diastolic interventricular septum thickness (Pearson index r = -0.42). Patients showing greater improvement in LVEF were those with less than moderate hypertrophy.

Conclusions

Patients with depressed systolic function show a consistent and early LVEF recovery after TAVI. An impaired LVEF recovery is most likely among patients with more than moderate hypertrophy, probably responsible of left ventricular fibrosis that irremediably compromises systolic function.

Detection of concentric left ventricular wall hypertrophy by contrast-enhanced non-electrocardiogram-gated chest computed tomography

BACKGROUND

No established measure of concentric left ventricular wall hypertrophy (cLVH) on routine computed tomography (CT) of the adult chest currently exists. The objective of this study was to identify and test linear measures for the detection of cLVH using transthoracic echocardiography (TTE) as the reference standard.

METHODS

Contrast-enhanced non-electrocardiogram-gated chest CTs acquired within two weeks of TTE were retrospectively evaluated. Two radiologists independently made trans-axial measurements in the proximal half of the left ventricle at its approximate widest internal diameter: maximum septal thickness (sept), maximum lateral wall thickness (lat), and inner (I_d) and outer (O_d) wall-wall diameters at the level of greatest combined myocardial thickness. The sum of sept and lat, hereafter Th_max, and modified cross-sectional area (A_mod = O_d² - I_d²) were calculated. Sept, lat, Th_max, and A_mod were evaluated by receiver operating characteristic (ROC) curves using TTE as the reference standard. Thresholds were optimized for specificity and applied to a validation cohort. Inter-rater agreement was assessed by a simple unweighted Kappa statistic (κ).

RESULTS

Sept and A_mod were selected based on areas under the ROC curves of 0.75 and 0.71, respectively, using 100 CTs. Thresholds of 1.6 cm and 30 cm², respectively, showed similar specificities of 98% with sensitivities of 27% and 30%, respectively. Applied to a validation cohort of 100 CTs, sept had higher combined positive predictive value (75%), inter-rater agreement (κ = 0.58), specificity (91%), and sensitivity (24%).

CONCLUSION

Linear measures demonstrate utility in the diagnosis of cLVH on routine contrast-enhanced chest CT.

T1 mapping in cardiac MRI

Quantitative myocardial and blood T1 have recently achieved clinical utility in numerous pathologies, as they provide non-invasive tissue characterization with the potential to replace invasive biopsy. Native T1 time (no contrast agent), changes with myocardial extracellular water (edema, focal or diffuse fibrosis), fat, iron, and amyloid protein content. After contrast, the extracellular volume fraction (ECV) estimates the size of the extracellular space and identifies interstitial disease. Spatially resolved quantification of these biomarkers (so-called T1 mapping and ECV mapping) are steadily becoming diagnostic and prognostically useful tests for several heart muscle diseases, influencing clinical decision-making with a pending second consensus statement due mid-2017. This review outlines the physics involved in estimating T1 times and summarizes the disease-specific clinical and research impacts of T1 and ECV to date. We conclude by highlighting some of the remaining challenges such as their community-wide delivery, quality control, and standardization for clinical practice.

Pathophysiology of Aortic Valve Stenosis: Is It Both Fibrocalcific and Sex Specific?

Our understanding of the fundamental biology and identification of efficacious therapeutic targets in aortic valve stenosis has lagged far behind the fields of atherosclerosis and heart failure. In this review, we highlight the most clinically relevant problems facing men and women with fibrocalcific aortic valve stenosis, discuss the fundamental biology underlying valve calcification and fibrosis, and identify key molecular points of intersection with sex hormone signaling.