Cardiac Damage and Conduction Disorders after Transcatheter Aortic Valve Implantation

Recently, a staging system using 4 grades has been proposed to quantify the extent of cardiac damage associated with aortic stenosis (AS), namely AS-related cardiac damage staging (ASCDS). ASCDS is independently associated with all-cause mortality and important clinical outcomes. To evaluate whether it might be associated with the occurrence of conduction system disorders after TAVI, a total of 119 symptomatic patients with severe AS who underwent a TAVI were categorized according to ASCDS: group 1 (13.5%): no or LV damage; group 2 (58.8%): left atrial/mitral valve damage, atrial fibrillation (AF); group 3 (27.7%): low-flow state, pulmonary vasculature/tricuspid valve/RV damage. After TAVI, 34% of patients exhibited LBBB and 10% high-degree atrioventricular block (HD-AVB). No patient in group 1 developed HD-AVB whereas new LBBB was frequent in groups 2 and 3. Twenty-one patients presented with paroxysmal AF with a higher rate for each group increment (group 1: n = 0, 0%; group 2: n = 11, 15.7%; group 3: n = 10, 30.3%) (p = 0.012). Patients in group 3 had the higher rate of permanent pacemaker implantation (PPMI) (group 1: n = 1, 6.3%; group 2: n = 7, 10%; group 3: n = 9, 27.3%) (p = 0.012). In conclusion, ASCDS might help identify patients at higher risk of conduction disorders and PPMI requirement after TAVI.

TAVI after More Than 20 Years

It has been more than 20 years since the first in man transcatheter aortic valve intervention (TAVI), and during this period we have witnessed an impressive evolution of this technique, with an extension of its use from non-operable patients to high-, intermediate- and even low-risk patients with aortic stenosis, and with a decrease in the incidence of complications. In this review, we discuss the evaluation of patients before TAVI, the procedure and the changes it has seen over time, and we present the current main complications and challenges of TAVI.

A new integrative approach combining right heart catheterization and echocardiography to stage aortic stenosis-related cardiac damage

Introduction

Although staging of the extent of aortic stenosis (AS)-related cardiac damages is usually performed via echocardiography, this technique has considerable limitations in assessing pulmonary artery and right chamber pressures. The present hypothesis-generating study sought to explore the efficacy of a staging system of cardiac damage based on echocardiographic and invasive [right heart catheterization (RHC)] hemodynamic parameters in patients undergoing transcatheter aortic valve implantation (TAVI).

Methods

We studied 90 symptomatic patients with severe AS in whom echocardiographic and invasive evaluation by RHC was obtained prior to TAVI. Cardiac damage stages were defined as follows: no cardiac damage (stage 0), left ventricular (LV) damage (stage 1), left atrial or mitral valve damage (stage 2), pulmonary vasculature or tricuspid valve damage (stage 3), and right ventricular (RV) dysfunction or low-flow state (stage 4). With the integrative approach using RHC, pulmonary hypertension (PH) was defined as an mPAP ≥25 mmHg and the low-flow state corresponded to a cardiac index of <1.8 L/min/m2 and a right atrial pressure of >10 mmHg.

Results

During follow-up (median: 2.9 years), 43 patients (47.8%) died. The integrative cardiac damage staging was associated with a significant increase in all-cause and cardiovascular mortality per each increase of cardiac damage stage, whereas the outcome was similar according to the echocardiographic staging.

Conclusions

A staging system of cardiac lesion based on echocardiographic and invasive hemodynamic parameters in patients with severe AS undergoing TAVI predicts mortality. Patients with pre-existing PH, ≥ moderate tricuspid regurgitation and/or RV dysfunction, and a low-flow state had a markedly increased risk of death. Further larger studies are needed to validate our findings.

Prognostic Value of Non-Invasive Global Myocardial Work in Asymptomatic Aortic Stenosis

This study aimed to evaluate the modification of non-invasive myocardial work (MW) indices related to aortic stenosis (AS) stages of cardiac damage and their prognostic value. The echocardiographic and outcome data of 170 patients, with asymptomatic moderate-to-severe AS and left ventricular ejection fraction (LVEF) ≥ 50%, and 50 age- and sex-comparable healthy controls were analysed. Primary endpoints were the occurrence of all-cause and cardiovascular death. Increased values of the global work index (GWI), global constructive work (GCW), and global wasted work (GWW) were observed in AS patients compared to controls (GWI: 2528 ± 521 vs. 2005 ± 302 mmHg%, GCW: 2948 ± 598 vs. 2360 ± 353 mmHg%, p < 0.001; GWW: 139 ± 90 vs. 90 ± 49 mmHg%, p = 0.005), with no changes in the global work efficiency. When patients were stratified according to the stages of cardiac damage, the GWI showed lower values in Stage 3−4 as compared to Stage 0 and Stage 2 (p = 0.024). During a mean follow-up of 30 months, 27 patients died. In multivariable Cox-regression analysis, adjusted for confounders, GWI (HR: 0.998, CI: 0.997−1.000; p = 0.034) and GCW (HR:0.998, CI: 0.997−0.999; p = 0.003) were significantly associated with excess mortality. When used as categorical variables, a GWI ≤ 1951 mmHg% and a GCW ≤ 2475 mmHg% accurately predicted all-cause and cardiovascular death at 4-year follow-up. In conclusion, in asymptomatic patients with moderate-to-severe AS, reduced values of GWI and GCW are associated with increased mortality. Therefore, the evaluation of MW indices may allow for a better identification of asymptomatic patients with moderate to severe AS and preserved LVEF whom are at increased risk of worse prognosis during follow-up.

Differential Biological Effects of Dietary Lipids and Irradiation on the Aorta, Aortic Valve, and the Mitral Valve

Aims

Dietary cholesterol and palmitic acid are risk factors for cardiovascular diseases (CVDs) affecting the arteries and the heart valves. The ionizing radiation that is frequently used as an anticancer treatment promotes CVD. The specific pathophysiology of these distinct disease manifestations is poorly understood. We, therefore, studied the biological effects of these dietary lipids and their cardiac irradiation on the arteries and the heart valves in the rabbit models of CVD.

Methods and Results

Cholesterol-enriched diet led to the thickening of the aortic wall and the aortic valve leaflets, immune cell infiltration in the aorta, mitral and aortic valves, as well as aortic valve calcification. Numerous cells expressing α-smooth muscle actin were detected in both the mitral and aortic valves. Lard-enriched diet induced massive aorta and aortic valve calcification, with no detectable immune cell infiltration. The addition of cardiac irradiation to the cholesterol diet yielded more calcification and more immune cell infiltrates in the atheroma and the aortic valve than cholesterol alone. RNA sequencing (RNAseq) analyses of aorta and heart valves revealed that a cholesterol-enriched diet mainly triggered inflammation-related biological processes in the aorta, aortic and mitral valves, which was further enhanced by cardiac irradiation. Lard-enriched diet rather affected calcification- and muscle-related processes in the aorta and aortic valve, respectively. Neutrophil count and systemic levels of platelet factor 4 and ent-8-iso-15(S)-PGF2α were identified as early biomarkers of cholesterol-induced tissue alterations, while cardiac irradiation resulted in elevated levels of circulating nucleosomes.

Conclusion

Dietary cholesterol, palmitic acid, and cardiac irradiation combined with a cholesterol-rich diet led to the development of distinct vascular and valvular lesions and changes in the circulating biomarkers. Hence, our study highlights unprecedented specificities related to common risk factors that underlie CVD.

Correlation between non-invasive myocardial work indices and main parameters of systolic and diastolic function: results from the EACVI NORRE study

AIMS

The present study sought to evaluate the correlation between indices of non-invasive myocardial work (MW) and left ventricle (LV) size, traditional and advanced parameters of LV systolic and diastolic function by 2D echocardiography (2DE).

METHODS AND RESULTS

A total of 226 (85 men, mean age: 45 ± 13 years) healthy subjects were enrolled at 22 collaborating institutions of the Normal Reference Ranges for Echocardiography (NORRE) study. Global work index (GWI), global constructive work (GCW), global work waste (GWW), and global work efficiency (GWE) were estimated from LV pressure-strain loops using custom software. Peak LV pressure was estimated non-invasively from brachial artery cuff pressure. LV size, parameters of systolic and diastolic function and ventricular-arterial coupling were measured by echocardiography. As advanced indices of myocardial performance, global longitudinal strain (GLS), global circumferential strain (GCS), and global radial strain (GRS) were obtained. On multivariable analysis, GWI was significantly correlated with GLS (standardized beta-coefficient = -0.23, P < 0.001), ejection fraction (EF) (standardized beta-coefficient = 0.15, P = 0.02), systolic blood pressure (SBP) (standardized beta-coefficient = 0.56, P < 0.001) and GRS (standardized beta-coefficient = 0.19, P = 0.004), while GCW was correlated with GLS (standardized beta-coefficient = -0.55, P < 0.001), SBP (standardized beta-coefficient = 0.71, P < 0.001), GRS (standardized beta-coefficient = 0.11, P = 0.02), and GCS (standardized beta-coefficient = -0.10, P = 0.01). GWE was directly correlated with EF and inversely correlated with Tei index (standardized beta-coefficient = 0.18, P = 0.009 and standardized beta-coefficient = -0.20, P = 0.004, respectively), the opposite occurred for GWW (standardized beta-coefficient =--0.14, P = 0.03 and standardized beta-coefficient = 0.17, P = 0.01, respectively).

CONCLUSION

The non-invasive MW indices show a good correlation with traditional 2DE parameters of myocardial systolic function and myocardial strain.

Layer-specific strain and the degree of left ventricular thickness in patients with hypertrophic cardiomyopathy

Background

Left ventricular (LV) wall thickness is an important parameter for the diagnosis of hypertrophic cardiomyopathy (HCM) and is also associated with long-term clinical outcome in HCM patients. However, conventional tools have failed to analyze the mechanisms of structural and functional abnormalities that occur at the cellular level in hypertrophied myocardial tissue. Recently, technological progression of 2D-speckle tracking echocardiography (2D-STE) has enabled the estimation of layer-specific strain (LSS), such as epicardial, mid-myocardial, and endocardial longitudinal strain, respectively. LSS may have the potential to elucidate the detailed mechanisms of myocardial dysfunction.

Purpose

The aim of this study was (i) to clarify the detailed mechanisms of structural and functional abnormalities of myocardial tissue in HCM using LSS (ii) to investigate the diagnostic accuracy of LSS for HCM.

Methods

Forty-one patients with HCM and preserved LV ejection fraction (LVEF) (66% male, 52±18 years, LVEF 62.9±3.7%) and 41 controls matched for age and sex (66% male, 52±20 years, LVEF 63.5±8.2%) underwent 2D-STE (GE-Healthcare, Vivid-E9). Quantitative strain values of epicardial, mid-myocardial, and endocardial layers were measured.

Results

LV wall thickness including interventricular septum thickness (HCM vs. Controls; 18.9±5.0 vs. 9.1±1.8, p&lt;0.001), posterior wall thickness (11.5±2.5 vs. 8.8±1.9, p&lt;0.001), and maximum wall thickness (20.1±4.3 vs. 9.4±0.4, p&lt;0.001) were significantly lower in HCM than in Controls. Absolute values of LSS for all layers were lower in HCM than in Controls (HCM vs. Controls; epicardial; −13.1±3.3 vs. −19.5±1.6, p&lt;0.001; mid-myocardial; −15.8±3.3 vs. −21.4±1.7, p&lt;0.001; endocardial; −18.9±3.9 vs. −23.6±1.9, p&lt;0.001). End/Epi ratio was higher in HCM than in Controls (HCM vs. Controls; 1.5±0.2 vs. 1.2±0.0, p&lt;0.001). Next, we investigated the echocardiographic parameters that correlated with LV maximal wall thickness (MWT). End/Epi ratio was an independent predictor of LV MWT (β=0.96, p&lt;0.001). Receiver operating characteristic analysis revealed that a higher End/Epi ratio (≥1.3) was the strongest predictor of diagnostic criteria for HCM (LV wall thickness ≥15 mm) (area under the curve 0.99, p&lt;0.001, sensitivity 98%, specificity 97%).

Conclusions

In HCM patients with preserved LVEF, (i) LSS was lower and End/Epi ratio was higher than in controls. (ii) End/Epi ratio (≥1.3) was the strongest predictor of abnormal wall thickness of HCM. The mechanism of higher End/Epi ratio in HCM might be attributable to the more common myofibrillar disarray in mid- and epicardial layers. Variations of LSS represented by End/Epi ratio might have the potential to accurately detect HCM and to elucidate the pathophysiology of impaired LV wall motion at cellular level in HCM.

Funding Acknowledgement

Type of funding source: None

Echocardiographic reference ranges for normal left ventricular layer-specific strain: results from the EACVI NORRE study

AIMS

To obtain the normal range for 2D echocardiographic (2DE) measurements of left ventricular (LV) layer-specific strain from a large group of healthy volunteers of both genders over a wide range of ages.

METHODS AND RESULTS

A total of 287 (109 men, mean age: 46 ± 14 years) healthy subjects were enrolled at 22 collaborating institutions of the EACVI Normal Reference Ranges for Echocardiography (NORRE) study. Layer-specific strain was analysed from the apical two-, three-, and four-chamber views using 2DE software. The lowest values of layer-specific strain calculated as ±1.96 standard deviations from the mean were -15.0% in men and -15.6% in women for epicardial strain, -16.8% and -17.7% for mid-myocardial strain, and -18.7% and -19.9% for endocardial strain, respectively. Basal-epicardial and mid-myocardial strain decreased with age in women (epicardial; P = 0.008, mid-myocardial; P = 0.003) and correlated with age (epicardial; r = -0.20, P = 0.007, mid-myocardial; r = -0.21, P = 0.006, endocardial; r = -0.23, P = 0.002), whereas apical-epicardial, mid-myocardial strain increased with the age in women (epicardial; P = 0.006, mid-myocardial; P = 0.03) and correlated with age (epicardial; r = 0.16, P = 0.04). End/Epi ratio at the apex was higher than at the middle and basal levels of LV in men (apex; 1.6 ± 0.2, middle; 1.2 ± 0.1, base 1.1 ± 0.1) and women (apex; 1.6 ± 0.1, middle; 1.1 ± 0.1, base 1.2 ± 0.1).

CONCLUSION

The NORRE study provides useful 2DE reference ranges for novel indices of layer-specific strain.

Impact of aortic stenosis on layer-specific longitudinal strain: relationship with symptoms and outcome

Aims

The present study sought to assess the impact of aortic stenosis (AS) on myocardial function as assessed by layer-specific longitudinal strain (LS) and its relationship with symptoms and outcome.

Methods and results

We compared 211 patients (56% males, mean age 73 ± 12 years) with severe AS and left ventricular ejection fraction (LVEF) ≥50% (114 symptomatic, 97 asymptomatic) with 50 controls matched for age and sex. LS was assessed from endocardium, mid-myocardium, and epicardium by 2D speckle-tracking echocardiography. Despite similar LVEF, multilayer strain values were significantly lower in symptomatic patients, compared to asymptomatic and controls [global LS: 17.9 ± 3.4 vs. 19.1 ± 3.1 vs. 20.7 ± 2.1%; endocardial LS: 20.1 ± 4.9 vs. 21.7 ± 4.2 vs. 23.4 ± 2.5%; epicardial LS: 15.8 ± 3.1 vs. 16.8 ± 2.8 vs. 18.3 ± 1.8%; P < 0.001 for all]. On multivariable logistic regression analysis, endocardial LS was independently associated to symptoms (P = 0.012), together with indexed left atrial volume (P = 0.006) and LV concentric remodelling (P = 0.044). During a mean follow-up of 22 months, 33 patients died of a cardiovascular event. On multivariable Cox-regression analysis, age (P = 0.029), brain natriuretic peptide values (P = 0.003), LV mass index (P = 0.0065), LV end-systolic volume (P = 0.012), and endocardial LS (P = 0.0057) emerged as independently associated with cardiovascular death. The best endocardial LS values associated with outcome was 20.6% (sensitivity 70%, specificity 52%, area under the curve = 0.626, P = 0.022). Endocardial LS (19.1 ± 3.3 vs. 20.7 ± 3.3, P = 0.02) but not epicardial LS (15.2 ± 2.8 vs. 15.9 ± 2.5, P = 0.104) also predicted the outcome in patients who were initially asymptomatic.

Conclusion

In patients with severe AS, LS impairment involves all myocardial layers and is more prominent in the advanced phases of the disease, when the symptoms occur. In this setting, the endocardial LS is independently associated with symptoms and patient outcome.

Echo-Doppler estimation of left ventricular filling pressure: results of the multicentre EACVI Euro-Filling study

Aims

The present Euro-Filling report aimed at comparing the diagnostic accuracy of the 2009 and 2016 echocardiographic grading algorithms for predicting invasively measured left ventricular filling pressure (LVFP).

Method and results

A total of 159 patients who underwent simultaneous evaluation of echo estimates of LVFP and invasive measurements of LV end-diastolic pressure (LVEDP) were enrolled at nine EACVI centres. Thirty-nine (25%) patients had a reduced LV ejection fraction (<50%), 77 (64%) were in NYHA ≥ II, and 85 (53%) had coronary artery disease. Sixty-four (40%) patients had elevated LVEDP (≥15 mmHg). Taken individually, all echocardiographic Doppler estimates of LVFP (E/A, E/e', left atrial volume, tricuspid regurgitation jet velocity) were marginally correlated with LVEDP. By using the 2016 recommendations, 65% of patients with normal non-invasive estimate of LVFP had normal LVEDP, while 79% of those with elevated non-invasive LVFP had elevated invasive LVEDP. By using 2009 recommendations, 68% of the patients with normal non-invasive LVFP had normal LVEDP, while 55% of those with elevated non-invasive LVFP had elevated LVEDP. The 2016 recommendations (sensitivity 75%, specificity 74%, positive predictive value 39%, negative predictive value 93%, AUC 0.78) identified slightly better patients with elevated invasive LVEDP (≥ 15 mmHg) as compared with the 2009 recommendations (sensitivity 43%, specificity 75%, positive predictive value 49%, negative predictive value 71%, AUC 0.68).

Conclusion

The present Euro-Filling study demonstrates that the new 2016 recommendations for assessing LVFP non-invasively are fairly reliable and clinically useful, as well as superior to the 2009 recommendations in estimating invasive LVEDP.