Evaluation of Left Ventricular Filling Pressures by Doppler Echocardiography in Patients With Hypertrophic Cardiomyopathy: Correlation With Direct Left Atrial Pressure Measurement at Cardiac Catheterization

Canadian Cardiovascular Society Clinical Practice Update on Contemporary Management of the Patient With Hypertrophic Cardiomyopathy

Numerous guidelines on the diagnosis and management of hypertrophic cardiomyopathy (HCM) have been published, by learned societies, over the past decade. Although helpful they are often long and less adapted to nonexperts. This writing panel was challenged to produce a document that grew as much from years of practical experience as it did from the peer-reviewed literature. As such, rather than produce yet another set of guidelines, we aim herein to deliver a concentrate of our own experiential learning and distill for the reader the essence of effective and appropriate HCM care. This Clinical Practice Update on HCM is therefore aimed at general cardiologists and other cardiovascular practitioners rather than for HCM specialists. We set the stage with a description of the condition and its clinical presentation, discuss the central importance of "obstruction" and how to look for it, review the role of cardiac magnetic resonance imaging, reflect on the appropriate use of genetic testing, review the treatment options for symptomatic HCM-crucially including cardiac myosin inhibitors, and deal concisely with practical issues surrounding risk assessment for sudden cardiac death, and management of the end-stage HCM patient. Uniquely, we have captured the pediatric experience on our panel to discuss appropriate differences in the management of younger patients with HCM. We ask the reader to remember that this document represents expert consensus opinion rather than dogma and to use their best judgement when dealing with the HCM patient in front of them.

2024 AHA/ACC/AMSSM/HRS/PACES/SCMR Guideline for the Management of Hypertrophic Cardiomyopathy: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2024 AHA/ACC/AMSSM/HRS/PACES/SCMR Guideline for the Management of Hypertrophic Cardiomyopathy" provides recommendations to guide clinicians in the management of patients with hypertrophic cardiomyopathy.

METHODS

A comprehensive literature search was conducted from September 14, 2022, to November 22, 2022, encompassing studies, reviews, and other evidence on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through May 23, 2023, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Hypertrophic cardiomyopathy remains a common genetic heart disease reported in populations globally. Recommendations from the "2020 AHA/ACC Guideline for the Diagnosis and Treatment of Patients With Hypertrophic Cardiomyopathy" have been updated with new evidence to guide clinicians.

2024 AHA/ACC/AMSSM/HRS/PACES/SCMR Guideline for the Management of Hypertrophic Cardiomyopathy: A Report of the American Heart Association/American College of Cardiology Joint Committee on Clinical Practice Guidelines

AIM

The "2024 AHA/ACC/AMSSM/HRS/PACES/SCMR Guideline for the Management of Hypertrophic Cardiomyopathy" provides recommendations to guide clinicians in the management of patients with hypertrophic cardiomyopathy.

METHODS

A comprehensive literature search was conducted from September 14, 2022, to November 22, 2022, encompassing studies, reviews, and other evidence on human subjects that were published in English from PubMed, EMBASE, the Cochrane Library, the Agency for Healthcare Research and Quality, and other selected databases relevant to this guideline. Additional relevant studies, published through May 23, 2023, during the guideline writing process, were also considered by the writing committee and added to the evidence tables, where appropriate.

STRUCTURE

Hypertrophic cardiomyopathy remains a common genetic heart disease reported in populations globally. Recommendations from the "2020 AHA/ACC Guideline for the Diagnosis and Treatment of Patients With Hypertrophic Cardiomyopathy" have been updated with new evidence to guide clinicians.

MR 4D flow-derived left atrial acceleration factor for differentiating advanced left ventricular diastolic dysfunction

OBJECTIVES

The magnetic resonance (MR) 4D flow imaging-derived left atrial (LA) acceleration factor α was recently introduced as a means to non-invasively estimate LA pressure. We aimed to investigate the association of α with the severity of left ventricular (LV) diastolic dysfunction using echocardiography as the reference method.

METHODS

Echocardiographic assessment of LV diastolic function and 3-T cardiac MR 4D flow imaging were prospectively performed in 94 subjects (44 male/50 female; mean age, 62 ± 12 years). LA early diastolic peak outflow velocity (vE), systolic peak inflow velocity (vS), and early diastolic peak inflow velocity (vD) were evaluated from 4D flow data. α was calculated from α = vE / [(vS + vD) / 2]. Mean parameter values were compared by t-test; diagnostic performance of α in predicting diastolic (dys)function was investigated by receiver operating characteristic curve analysis.

RESULTS

Mean α values were 1.17 ± 0.14, 1.20 ± 0.08, 1.33 ± 0.15, 1.77 ± 0.18, and 2.79 ± 0.69 for grade 0 (n = 51), indeterminate (n = 9), grade I (n = 13), grade II (n = 13), and grade III (n = 8) LV diastolic (dys)function, respectively. α differed between subjects with non-advanced (grade < II) and advanced (grade ≥ II) diastolic dysfunction (1.20 ± 0.15 vs. 2.16 ± 0.66, p < 0.001). The area under the curve (AUC) for detection of advanced diastolic dysfunction was 0.998 (95% CI: 0.958-1.000), yielding sensitivity of 100% (95% CI: 84-100%) and specificity of 99% (95% CI: 93-100%) at cut-off α ≥ 1.58. The AUC for differentiating grade III diastolic dysfunction was also 0.998 (95% CI: 0.976-1.000) at cut-off α ≥ 2.14.

CONCLUSION

The 4D flow-derived LA acceleration factor α allows grade II and grade III diastolic dysfunction to be distinguished from non-advanced grades as well as from each other.

CLINICAL RELEVANCE STATEMENT

As a single continuous parameter, the 4D flow-derived LA acceleration factor α shows potential to simplify the multi-parametric imaging algorithm for diagnosis of advanced LV diastolic dysfunction, thereby identifying patients at increased risk for cardiovascular events.

KEY POINTS

• Detection of advanced diastolic dysfunction is typically performed using a complex, multi-parametric approach. • The 4D flow-derived left atrial acceleration factor α alone allows accurate detection of advanced left ventricular diastolic dysfunction. • As a single continuous parameter, the left atrial acceleration factor α could simplify the diagnosis of advanced diastolic dysfunction.

Association of Impaired Left Ventricular Mitral Filling from 4D Flow Cardiac MRI and Prognosis of Hypertrophic Cardiomyopathy

Purpose To investigate whether the peak early filling rate normalized to the filling volume (PEFR/FV) estimated from four-dimensional (4D) flow cardiac MRI may be used to assess impaired left ventricular (LV) filling and predict clinical outcomes in individuals with hypertrophic cardiomyopathy (HCM). Materials and Methods Cardiac MRI with a 4D flow sequence and late gadolinium enhancement (LGE), as well as echocardiography, was performed in 88 individuals: 44 participants with HCM from a French prospective registry (ClinicalTrials.gov; NCT01091480) and 44 healthy volunteers matched for age and sex. In participants with HCM, a composite primary end point was assessed at follow-up, including unexplained syncope, new-onset atrial fibrillation, hospitalization for congestive heart failure, ischemic stroke, sustained ventricular arrhythmia, septal reduction therapy, and cardiac death. A Cox proportional hazard model was used to analyze associations with the primary end point. Results PEFR/FV was significantly lower in the HCM group (mean age, 51.8 years ± 18.5 [SD]; 29 male participants) compared with healthy volunteers (mean, 3.35 sec-1 ± 0.99 [0.90-5.20] vs 4.42 sec-1 ± 1.68 [2.74-11.86]; P < .001) and correlated with both B-type natriuretic peptide (BNP) level (r = -0.31; P < .001) and the ratio of pulsed Doppler early transmitral inflow to Doppler tissue imaging annulus velocities (E/E'; r = -0.54; P < .001). At a median follow-up of 2.3 years (IQR, 1.7-3.3 years), the primary end point occurred in 14 (32%) participants. A PEFR/FV of 2.61 sec-1 or less was significantly associated with occurrence of the primary end point (hazard ratio, 9.46 [95% CI: 2.61, 45.17; P < .001] to 15.21 [95% CI: 3.51, 80.22; P < .001]), independently of age, BNP level, E/E', LGE extent, and LV and left atrial strain according to successive bivariate models. Conclusion In HCM, LV filling evaluated with 4D flow cardiac MRI correlated with Doppler and biologic indexes of diastolic dysfunction and predicted clinical outcomes. Keywords: Diastolic Function, Left Ventricular Filling, Hypertrophic Cardiomyopathy, Cardiac MRI, 4D Flow Sequence Clinical trial registration no. NCT01091480 Supplemental material is available for this article. © RSNA, 2024.

Role of Imaging in the Diagnosis, Evaluation, and Management of Hypertrophic Cardiomyopathy

Hypertrophic cardiomyopathy (HCM) is increasingly recognized and may benefit from the recent approval of new, targeted medical therapy. Successful management of HCM is dependent on early and accurate diagnosis. The lack of a definitive diagnostic test, the wide variation in phenotype and the commonness of phenocopy conditions, and the presence of normal or hyperdynamic left ventricular function in most patients makes HCM a condition that is highly dependent on imaging for all aspects of management including, diagnosis, classification, predicting risk of complications, detecting complications, identifying risk for ventricular arrhythmias, evaluating choice of therapy and monitoring therapy, intraprocedural guidance, and screening family members. Although echocardiographic imaging remains the mainstay in the diagnosis and subsequent management of HCM, this disease clearly requires multimethod imaging for various aspects of optimal patient care. Advances in echocardiography hardware and techniques, development and refinement of imaging with computed tomography, magnetic resonance, and nuclear scanning, and the emergence of very focused assessments such as diastology and fibrosis imaging have all advanced the diagnosis and management of HCM. In this review, we discuss the relative utility and evidence support for these imaging approaches to contribute to improve patient outcomes.

Left atrial remodeling in hypertrophic cardiomyopathy and Fabry disease: A CMR-based head-to-head comparison and outcome analysis

BACKGROUND

Hypertrophic cardiomyopathy (HCM) and Fabry disease cardiomyopathy (FD) are phenocopies, as they show left ventricular hypertrophy (LVH). The left atrium (LA) is emerging as a potential marker of disease severity in both cardiomyopathies. The present study compares HCM and FD cardiomyopathy with similar degree of LVH, exploring LA morpho-functional parameters and the correlates of clinical outcome.

METHODS

We performed a comprehensive CMR-based comparison between 30 HCM and 30 FD patients matched on age, sex, BSA, LV mass and major cardiovascular risk factors affecting LA remodeling (arterial hypertension and diabetes). 30 healthy controls were also included. CMR feature tracking (CMR-FT) analysis, T1 mapping and conventional parameters were evaluated. Patients also underwent transthoracic echocardiography for LV diastolic function assessment. Clinical events at follow-up were collected (atrial and ventricular events, bradyarrhythmia, heart failure (HF) hospitalization and death).

RESULTS

HCM patients showed greater LA remodeling compared to FD patients, namely higher LA end-systolic volume index (LAVi max), lower LA-ejection fraction (LA-EF) and worse reservoir (εs) and booster function (εa) (all p < 0.05). Accordingly, these parameters have demonstrated good potential for distinguishing between FD and HCM (AUC 0.68-0.73, all p < 0.05), with LAVi max being an independent predictor for HCM diagnosis (OR 1.07, 95%CI 1.011-1.132, p 0.02). Moreover, in HCM patients a significant association between εs and HF occurrence was observed at 2-year follow-up (OR 0.85, 95%CI 0.72-0.99, p 0.04).

CONCLUSIONS

In HCM, LA remodeling is greater than in FD cardiomyopathy with similar LVH, and reservoir strain is associated with HF at follow-up.

Due Diligence of a Diastolic Index as a Prognostic Factor in Heart Failure with Preserved Ejection Fraction

Of the existing non-invasive diastolic indices, none consider arterial load. This article reveals points of caution for determining the diastolic prognostic index using a novel index of vascular resistance-integrated diastolic function in old, real-world patients with heart failure with preserved ejection fraction (HFpEF) in Japan. This index represents the ratio of left ventricular diastolic elastance (Ed) to arterial elastance (Ea), where Ed/Ea = (E/e')/(0.9 × systolic blood pressure), showing a relative ratio of left atrial filling pressure to left ventricular end-systolic pressure. The role of hemodynamic prognostic factors related to diastolic function, such as Ed/Ea, may differ according to the clinical endpoint, follow-up duration, and sex. In HFpEF patients with heterogenous cardiac structure and function, an assessment using a serial echocardiographic diastolic index in clinical care can provide an accurate prognosis.

Imaging in Hypertrophic Cardiomyopathy: Beyond Risk Stratification

A multimodality imaging evaluation in hypertrophic cardiomyopathy is often used for risk stratification. Recent developments in imaging have allowed for better diagnosis, prognosis, and decision-making for a variety of therapies from medical to interventional. Echocardiography and magnetic resonance have been integral in evaluating subtype, left ventricular function, tissue characterization, left atrial measurements, valvular function, and presence of left ventricular aneurysm and outflow tract obstruction. These factors have helped to quantify risk of atrial fibrillation and determine the likely usefulness of pharmacologic therapy and septal reduction therapy. This review covers these in detail.

Echocardiographic Evaluation of Diastolic Function in Special Populations

Left ventricular (LV) diastolic dysfunction results from a combination of impaired relaxation, reduced restoring forces, and increased chamber stiffness. Noninvasive assessment of diastology uses a multiparametric approach involving surrogate markers of increased filling pressures, which include mitral inflow, septal and lateral annular velocities, tricuspid regurgitation velocity, and left atrial volume index. However, these parameters must be used cautiously. This is because the traditional algorithms for evaluating diastolic function and estimation of LV filling pressures (LVFPs), as recommended by the American Society of Echocardiography and European Association of Cardiovascular Imaging 2016 guidelines, do not apply to unique patients with underlying cardiomyopathies, significant valvular disease, conduction abnormalities, arrhythmias, LV assist devices, and heart transplants, which alter the relation between the conventional indexes of diastolic function and LVFP. The purpose of this review is to provide solutions for evaluating LVFP through illustrative examples of these special populations, incorporating supplemental Doppler indexes, such as isovolumic relaxation time, mitral deceleration time, and pulmonary venous flow analysis, as needed to formulate a more comprehensive approach.

The Value of Myocardial Fibrosis Parameters Derived from Cardiac Magnetic Resonance Imaging in Risk Stratification for Patients with Hypertrophic Cardiomyopathy

RATIONALE AND OBJECTIVES

The aim of the study was to determine whether myocardial fibrosis parameters of cardiac magnetic resonance imaging (MRI) has added value in the risk stratification of hypertrophic cardiomyopathy (HCM) patients.

MATERIALS AND METHODS

In this retrospective study, 108 patients with HCM (mean age ± standard deviation, 55.5 ± 13.4 years) were included from January 2019 to April 2022, and were followed up for 2 years to record sudden cardiac death (SCD) adverse events. All HCM patients underwent cardiac MRI and were divided into a training cohort (n = 81; mean age, 56.1 ± 13.0 years) and a validation cohort (n = 27; mean age, 57.8 ± 13.9 years). According to the presence of SCD risk factors defined by the 2020 AHA/ACC guidelines, HCM patients were classified into low-risk and high-risk groups. Cardiac MRI features, including late gadolinium enhancement (LGE), T1 mapping, and extracellular volume fraction (ECV), were assessed and compared between the two groups. Logistic regression analysis was used to select the optimal predictors of SCD from cardiac MRI features and HCM Risk-SCD score to construct prediction models. Receiver operating curve (ROC) analysis was used to assess the predictive performance of the constructed prediction model. Cox regression analysis was also used to determine the optimal predictors of SCD adverse events.

RESULTS

Multivariate logistic analysis showed that the global ECV was the single myocardial fibrosis parameter predictive of the risk of SCD (p < 0.001). The areas under the ROC curves (AUC) of global ECV were higher than those of LGE, global native T1, global postcontrast T1, and HCM Risk-SCD (AUC = 0.85 vs. 0.74, 0.77, 0.63, 0.78). An integrative risk stratification model combining global ECV (odds ratio, 1.36 [95% CI: 1.16-1.60]; p < 0.001) and HCM Risk-SCD score (odds ratio, 1.63 [95% CI: 1.08-2.47]; p < 0.001) achieved an AUC of 0.89 (95% CI: 0.81-0.96) in the training cohort, which was significantly higher than that of HCM Risk-SCD score alone (p = 0.03). The AUC of the integrative model was 0.93 (95% CI: 0.84-1.00) in the validation cohort. Multivariate Cox regression analysis also showed that the global ECV was an independent predictor of SCD adverse events (hazard ratio, 1.27 [95% CI: 1.10-1.47]).

CONCLUSION

The ECV derived from cardiac MRI is comparable to the HCM Risk-SCD scale in predicting the SCD risk stratification in patients with HCM.

Echo-Doppler and strain assessment of filling pressures in adults with congenitally corrected transposition and systemic right ventricles

AIMS

Systolic dysfunction of the systemic right ventricle (sRV) is common in adults with transposition of the great arteries and sRV. In acquired disease, diastology analysis for assessment of filling pressures (FP) is paramount in patient care.

METHODS AND RESULTS

Retrospective analysis of 47 adults with sRV without prior systemic tricuspid valve surgery undergoing catheterization and echocardiography within 7 days (median -2 [-1, -3]) from January 2000 to February 2021 at our institution. Median age was 48 (31, 55) years, and 16 (34.0%) patients were female. FPs were normal in 21 patients (44.7%). Left atrial size was enlarged in most patients (83.0%) with mean indexed value 58.3 ± 23.4 mL/m2. Tissue Doppler e' was not significantly different between those with high FPs vs. normal (medial 0.07 ± 0.03 vs. 0.08 ± 0.03 m/s, P = 0.63; lateral 0.08 ± 0.04 vs. 0.08 ± 0.04 m/s, P = 0.88). E velocity and subpulmonic mitral regurgitant velocity were higher in those with high FPs (0.9 ± 0.3 vs. 0.6 ± 0.2 m/s, P = 0.005; 3.8 ± 1.1 vs. 2.8 ± 0.9 m/s, P = 0.004). Left atrial reservoir strain, sRV global longitudinal strain, and subpulmonic left ventricular strain were worse in those with high FP (18.0 ± 7.6 vs. 27.9 ± 10.2%, P = 0.0009; -13.0 ± 4.4 vs. -17.9 ± 5.0%, P = 0.002; -16.8 ± 5.7 vs. -23.0 ± 3.8%, P = 0.001).

CONCLUSION

Despite the complex anatomy, FPs can be assessed non-invasively in adults with sRV without prior systemic tricuspid valve surgery. The current guideline algorithm for diastolic dysfunction in acquired heart disease has limited applicability in this population. Given the limitations of Doppler in this heterogeneous population, strain analysis can be a helpful adjunct for estimation of FPs.

Heart Failure with Preserved Ejection Fraction in Children

Diastolic dysfunction (DD) refers to abnormalities in the mechanical function of the left ventricle (LV) during diastole. Severe LVDD can cause symptoms and the signs of heart failure (HF) in the setting of normal or near normal LV systolic function and is referred to as diastolic HF or HF with preserved ejection fraction (HFpEF). Pediatric cardiologists have long speculated HFpEF in children with congenital heart disease and cardiomyopathy. However, understanding the risk factors, clinical course, and validated biomarkers predictive of the outcome of HFpEF in children is challenging due to heterogeneous etiologies and overlapping pathophysiological mechanisms. The natural history of HFpEF varies depending upon the patient's age, sex, race, geographic location, nutritional status, biochemical risk factors, underlying heart disease, and genetic-environmental interaction, among other factors. Pediatric onset HFpEF is often not the same disease as in adults. Advances in the noninvasive evaluation of the LV diastolic function by strain, and strain rate analysis with speckle-tracking echocardiography, tissue Doppler imaging, and cardiac magnetic resonance imaging have increased our understanding of the HFpEF in children. This review addresses HFpEF in children and identifies knowledge gaps in the underlying etiologies, pathogenesis, diagnosis, and management, especially compared to adults with HFpEF.

Spironolactone effect on cardiac structure and function of patients with heart failure and preserved ejection fraction: a pooled analysis of three randomized trials

AIMS

Spironolactone is currently used in a large proportion of patients with heart failure and preserved ejection fraction (HFpEF), yet its effect on cardiac structure and function in a large population has not been well established. The aim of this study was to evaluate the impact of spironolactone on key echocardiographic parameters in HFpEF.

METHODS AND RESULTS

An individual-patient-data meta-analysis of three randomized trials (HOMAGE, Aldo-DHF, and TOPCAT) was performed comparing spironolactone (9-12 month exposure) to placebo (or control) for the changes in left atrial volume index (LAVi), left ventricular mass index (LVMi), interventricular septum (IVS) thickness, E/e' ratio, and left ventricular ejection fraction (LVEF) among patients with stage B (HOMAGE) or C (Aldo-DHF and TOPCAT) HFpEF. Analysis of covariance was used to test the effect of spironolactone on echocardiographic changes. A total of 984 patients were included in this analysis: 452 (45.9%) from HOMAGE, 398 (40.4%) from Aldo-DHF, and 134 (13.6%) from TOPCAT. The pooled-cohort patient's median age was 71 (66-77) years and 39% were women. Median LAVi was 29 (24-35) ml/m² , LVMi 100 (84-118) g/m² , IVS thickness 12 (10-13) mm, E/e' ratio 11 (9-13), and LVEF 64 (59-69)%. Spironolactone reduced LAVi by -1.1 (-2.0 to -0.1) ml/m² (p = 0.03); LVMi by -3.6 (-6.4 to -0.8) g/m² (p = 0.01); IVS thickness by -0.2 (-0.3 to -0.1) mm (p = 0.01); E/e' ratio by -1.3 (-2.4 to -0.2) (p = 0.02); and increased LVEF by 1.7 (0.8-2.6)% (p < 0.01). No treatment-by-study heterogeneity was found except for E/e' ratio with a larger effect in Aldo-DHF and TOPCAT (interaction p < 0.01).

CONCLUSIONS

Spironolactone improved cardiac structure and function of patients with HFpEF.

Myosin Inhibition and Left Ventricular Diastolic Function in Patients With Obstructive Hypertrophic Cardiomyopathy Referred for Septal Reduction Therapy: Insights From the VALOR-HCM Study

BACKGROUND

In the randomized phase 3 VALOR-HCM study (A Study to Evaluate Mavacamten in Adults With Symptomatic Obstructive Hypertrophic Cardiomyopathy Who Are Eligible for Septal Reduction Therapy) of patients with obstructive hypertrophic cardiomyopathy, mavacamten reduced the need for septal reduction therapy. Because mavacamten improves ventricular compliance, this sub-study examined the effects of treatment with this cardiac myosin inhibitor on diastolic function.

METHODS

Symptomatic obstructive hypertrophic cardiomyopathy patients on maximally tolerated medical therapy referred for septal reduction therapy were randomized 1:1 to mavacamten or placebo. At baseline and week 16, a resting and stress echocardiogram was performed with interpretation by a core laboratory. In this exploratory substudy, the principal end point was the change in parameters used to define the grade of diastolic function in patients treated with mavacamten and placebo. A related objective was to assess the proportion of patients with an improvement in diastolic function grade. A secondary aim was to assess for correlation between diastolic function parameters and the secondary end points from VALOR-HCM: New York Heart Association class, quality of life, and cardiac biomarkers.

RESULTS

Diastolic dysfunction grade was evaluable in 98 patients at baseline and week 16. Among patients treated with mavacamten, 29.4% (15 of 51) demonstrated improvement in diastolic function grade compared with 12.8% (6 of 47) patients with placebo (P=0.05). Average E/e' ratio decreased significantly in patients treated with mavacamten (-3.4±5.3) compared with placebo (0.57±3.5; P<0.001). Indexed left atrial volumes (mL/m²) also decreased significantly in patients who received mavacamten (-5.2±7.8) compared with placebo (-0.51±8.1; P=0.005). After adjustment for change in left ventricular outflow tract gradient and mitral regurgitation, mavacamten was significantly associated with a decrease in average E/e' ratio and indexed left atrial volumes. Change in average E/e' ratio was significantly correlated with the secondary end points from VALOR-HCM.

CONCLUSIONS

In this exploratory substudy, after 16 weeks of therapy, mavacamten improved diastolic function, and this change correlated with improvement in clinical and biomarker end points.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT04349072.

Correlation between Echocardiographic Diastolic Parameters and Invasive Measurements of Left Ventricular Filling Pressure in Patients with Takotsubo Cardiomyopathy

BACKGROUND

The extent of diastolic dysfunction is of clinical importance in the risk stratification and management of patients with Takotsubo cardiomyopathy (TC). Standard echocardiographic indices of diastolic dysfunction have robust predictive ability in assorted disease states, but have not been validated in TC. The aim of this study was to compare Doppler metrics of diastolic function against catheterization-measured filling pressures in TC.

METHODS

Patients with TC who met inclusion and exclusion criteria were evaluated using echocardiography and catheterization performed within 24 hours. Both left ventricular (LV) end-diastolic pressure and LV pre-A diastolic pressure were obtained from catheterization tracings. The echocardiographic parameters for diastolic function were extracted using the American Society of Echocardiography recommendations and a previously validated regression equation for mean left atrial pressure (mLAP).

RESULTS

A total of 51 patients with TC were included. Patients were predominantly women (72.5%), with a mean age of 58 ± 13 years and a mean ejection fraction of 24 ± 10 %. E/e' ratio (septal, average, and lateral) and calculated mLAP correlated positively with catheterization LV pre-A, with fair to moderate correlation (coefficient range, 0.38-0.44). The t-test mean difference between LV pre-A pressure and calculated mLAP was 0.77 ± 7.34 mm Hg (95% CI, ±14.68 mm Hg) suggesting inconsistent measures. mLAP also exhibited poor diagnostic ability to discriminate elevated LV pre-A diastolic pressure, with an area under the receiver operating characteristic curve of 0.69 (95% CI, 0.50-0.88).

CONCLUSIONS

Commonly used echocardiographic parameters for diastolic function demonstrated less-than-optimal correlation, with poor sensitivity and specificity, compared with invasively measured LV end-diastolic pressure or LV pre-A wave diastolic pressure in patients with TC. Precise characterization of LV filling pressure in patients with TC using contemporary noninvasive echocardiographic parameters appears challenging. Invasive measurements of filling pressure should remain the gold standard for optimal risk stratification and management of patients with TC.

Automatic quantitative measurement of left atrial pressure using mitral regurgitation spectrum: clinical study on comparison with floating catheter

Introduction

To explore how to measure LAPEq accurately and quantitatively, that is, the left atrial pressure (LAP) measured and calculated by equation method using mitral regurgitation spectrum.

Methods

The mitral regurgitation spectrum, pulmonary arteriolar wedge pressure (PAWP) and invasive arterial systolic pressure of radial artery of 28 patients were collected simultaneously, including 3 patients with rheumatic heart disease, 15 patients with mitral valve prolapse and 10 patients with coronary artery bypass grafting, patients with moderate or above aortic stenosis were excluded. LAPBp (Doppler sphygmomanometer method), LAPEq (Equation method) and LAPC (Catheter method) were measured synchronously, and the measurement results of the three methods were compared and analyzed. A special intelligent Doppler spectrum analysis software was self-designed to accurately measure LAPEq. This study had been approved by the ethics committee of the Northern Theater General Hospital (K-2019-17), and applied for clinical trial (No. Chictr 190023812).

Results

It was found that there was no significant statistical difference between the measurement results of LAPC and LAPEq (t = 0.954, P = 0.348), and significant correlation between the two methods [r = 0.908(0.844, 0.964), P < 0.001]. Although the measurement results of LAPC and LAPBP are consistent in the condition of non-severe eccentric mitral regurgitation, there are significant differences in the overall case and weak correlation between the two methods [r = 0.210, (−0.101, 0.510), P = 0.090]. In MVP patients with P1 or P3 prolapse, the peak pressure difference of MR was underestimated due to the serious eccentricity of MR, which affected the accuracy of LAPBP measurement.

Conclusions

It was shown that there is a good correlation between LAPEq and LAPC, which verifies that the non-invasive and direct quantitative measurement of left atrial pressure based on mitral regurgitation spectrum is feasible and has a good application prospect.

Time-sensitive prognostic performance of an afterload-integrated diastolic index in heart failure with preserved ejection fraction: a prospective multicentre observational study

OBJECTIVES

The prognostic significance of an afterload-integrated diastolic index, the ratio of diastolic elastance (Ed) to arterial elastance (Ea) (Ed/Ea=[E/e']/[0.9×systolic blood pressure]), is valid for 1 year after discharge in older patients with heart failure with preserved ejection fraction (HFpEF). We aimed to clarify the association with changes in Ed/Ea from enrolment to 1 year and prognosis thereafter in patients with HFpEF.

SETTING

A prospective, multicentre observational registry of collaborating hospitals in Osaka, Japan.

PARTICIPANTS

We enrolled 659 patients with HFpEF hospitalised for acute decompensated heart failure (men/women: 296/363). Blood tests and transthoracic echocardiography were performed before discharge and at 1 year after.

PRIMARY OUTCOME MEASURES

All-cause mortality and/or re-admission for heart failure were evaluated after discharge.

RESULTS

High Ed/Ea assessed before discharge was a significant prognostic factor during the first, but not the second, year after discharge in all-cause mortality or all-cause mortality and/or re-admission for heart failure. When re-analysis was performed using the value of Ed/Ea at 1 year after discharge, high Ed/Ea was significant for the prognosis during the second year for both end points (p=0.012 and p=0.033, respectively). The poorest mortality during 1‒2 years after enrolment was observed in those who showed a worsening Ed/Ea during the first year associated with larger left ventricular mass index and reduced left ventricular ejection fraction. In all-cause mortality and/or re-admission for heart failure, the event rate during 1‒2 years was highest in those with persistently high Ed/Ea even after 1 year.

CONCLUSIONS

Time-sensitive prognostic performance of Ed/Ea, an afterload-integrated diastolic index, was observed in older patients with HFpEF.

TRIAL REGISTRATION NUMBER

UMIN000021831.

First-pass perfusion cardiovascular magnetic resonance parameters as surrogate markers for left ventricular diastolic dysfunction: a validation against cardiac catheterization

OBJECTIVES

The non-invasive assessment of left ventricular (LV) diastolic dysfunction remains a challenge. The role of first-pass perfusion cardiac magnetic resonance (CMR) parameters in quantitative hemodynamic analyses has been reported. We therefore aimed to validate the diagnostic ability and accuracy of such parameters against cardiac catheterization for LV diastolic dysfunction in patients with left heart disease (LHD).

METHODS

We retrospectively enrolled 77 LHD patients who underwent CMR imaging and cardiac catheterization. LV diastolic dysfunction was defined as pulmonary capillary wedge pressure (PCWP) or LV end-diastolic pressure (LVEDP) > 12 mmHg on catheterization. On first-pass perfusion CMR imaging, pulmonary transit time (PTT) was measured as the time for blood to pass from the left ventricle to the right ventricle (RV) through the pulmonary vasculature. Pulmonary transit beat (PTB) was the number of cardiac cycles within the interval, and pulmonary blood volume indexed to body surface area (PBVi) was the product of PTB and RV stroke volume index (RVSVi).

RESULTS

Of the 77 LHD patients, 53 (68.83%) were found to have LV diastolic dysfunction, and showed significantly higher PTTc, PTB, and PBVi (p < 0.05) compared with those without. In multivariate analyses, only PTTc and PTB were identified as independent predictors of LV diastolic dysfunction (p < 0.05). With an optimal cutoff of 11.9 s, PTTc yielded the best diagnostic performance for LV diastolic dysfunction (area under the curve = 0.83, p < 0.001).

CONCLUSIONS

PTTc may represent a non-invasive quantitative surrogate marker for the detection and assessment of diastolic dysfunction in LHD patients.

KEY POINTS

• PTTc yielded the best diagnostic accuracy for diastolic dysfunction, with an optimal cutoff of 11.9 s, and a specificity of 100%. • PTTc and PTB were found to be independent predictors of LV diastolic dysfunction across different multivariate models with high reproducibility. • PTTc is a promising non-invasive surrogate marker for the detection and assessment of diastolic dysfunction in LHD patients.

Recommendations for Multimodality Cardiovascular Imaging of Patients with Hypertrophic Cardiomyopathy: An Update from the American Society of Echocardiography, in Collaboration with the American Society of Nuclear Cardiology, the Society for Cardiovascular Magnetic Resonance, and the Society of Cardiovascular Computed Tomography

Hypertrophic cardiomyopathy (HCM) is defined by the presence of left ventricular hypertrophy in the absence of other potentially causative cardiac, systemic, syndromic, or metabolic diseases. Symptoms can be related to a range of pathophysiologic mechanisms including left ventricular outflow tract obstruction with or without significant mitral regurgitation, diastolic dysfunction with heart failure with preserved and heart failure with reduced ejection fraction, autonomic dysfunction, ischemia, and arrhythmias. Appropriate understanding and utilization of multimodality imaging is fundamental to accurate diagnosis as well as longitudinal care of patients with HCM. Resting and stress imaging provide comprehensive and complementary information to help clarify mechanism(s) responsible for symptoms such that appropriate and timely treatment strategies may be implemented. Advanced imaging is relied upon to guide certain treatment options including septal reduction therapy and mitral valve repair. Using both clinical and imaging parameters, enhanced algorithms for sudden cardiac death risk stratification facilitate selection of HCM patients most likely to benefit from implantable cardioverter-defibrillators.

Paradoxical prolongation of QT interval during exercise in patients with hypertrophic cardiomyopathy: cellular mechanisms and implications for diastolic function

Aims

Ventricular cardiomyocytes from hypertrophic cardiomyopathy (HCM) patient hearts show prolonged action potential duration (APD), impaired intracellular Ca²⁺ homeostasis and abnormal electrical response to beta -adrenergic stimulation. We sought to determine whether this behaviour is associated with abnormal changes of repolarization during exercise and worsening of diastolic function, ultimately explaining the intolerance to exercise experienced by some patients without obstruction.

Methods and results

Non-obstructive HCM patients (178) and control subjects (81) underwent standard exercise testing, including exercise echocardiography. Ventricular myocytes were isolated from myocardial samples of 23 HCM and eight non-failing non-hypertrophic surgical patients. The APD shortening in response to high frequencies was maintained in HCM myocytes, while β-adrenergic stimulation unexpectedly prolonged APDs, ultimately leading to a lesser shortening of APDs in response to exercise. In HCM vs. control subjects, we observed a lesser shortening of QT interval at peak exercise (QTc: +27 ± 52 ms in HCM, −4 ± 50 ms in controls, P < 0.0001). In patients showing a marked QTc prolongation (>30 ms), the excessive shortening of the electrical diastolic period was linked with a limited increase of heart-rate and deterioration of diastolic function at peak effort.

Conclusions

Abnormal balance of Ca²⁺- and K⁺-currents in HCM cardiomyocytes determines insufficient APD and Ca²⁺-transient shortening with exercise. In HCM patients, exercise-induced QTc prolongation was associated with impaired diastolic reserve, contributing to the reduced exercise tolerance. Our results support the idea that severe electrical cardiomyocyte abnormalities underlie exercise intolerance in a subgroup of HCM patients without obstruction.

Therapeutic Approaches in Heart Failure with Preserved Ejection Fraction (HFpEF) in Children: Present and Future

For a long time, pediatric heart failure (HF) with preserved systolic function (HFpEF) has been noted in patients with cardiomyopathies and congenital heart disease. HFpEF is infrequently reported in children and instead of using the  HFpEF terminology the HF symptoms are attributed to diastolic dysfunction. Identifying HFpEF in children is challenging because of heterogeneous etiologies and unknown pathophysiological mechanisms. Advances in echocardiography and cardiac magnetic resonance imaging techniques have further increased our understanding of HFpEF in children. However, the literature does not describe the incidence, etiology, clinical features, and treatment of HFpEF in children. At present, treatment of HFpEF in children is extrapolated from clinical trials in adults. There are significant differences between pediatric and adult HF with reduced ejection fraction, supported by a lack of adequate response to adult HF therapies. Evidence-based clinical trials in children are still not available because of the difficulty of conducting trials with a limited number of pediatric patients with HF. The treatment of HFpEF in children is based upon the clinician's experience, and the majority of children receive off-level medications. There are significant differences between pediatric and adult HFpEF pharmacotherapies in many areas, including side-effect profiles, underlying pathophysiologies, the β-receptor physiology, and pharmacokinetics and pharmacodynamics. This review describes the present and future treatments for children with HFpEF compared with adults. This review also highlights the need to urgently test new therapies in children with HFpEF to demonstrate the safety and efficacy of drugs and devices with proven benefits in adults.

Left atrial phasic echocardiographic functional analysis in relation to diastolic left ventricular hemodynamic parameters acquired during right heart catheterization

Introduction

Doppler echocardiography has become the leading non-invasive tool for hemodynamic screening and follow-up in various clinical situations. Our objective was to assess whether left atrium (LA) functional echocardiographic parameters correlate with hemodynamic left ventricle (LV) filling parameters measured during right heart catheterization (RHC) in various disease states.

Methods

Echocardiographic examinations of 71 consecutive patients that had RHC within 24 h were studied retrospectively using LA/LV feature tracking analysis. Echocardiographic and myocardial mechanics characteristics were then correlated with the RHC findings.

Results

The best correlation were demonstrated between the trans-tricuspid gradient in the echocardiogram and the right ventricle (RV) systolic pressure in the RHC (R² = 0.41, p < 0.0001). Mitral E/E’ annular velocity ratio did not correlate with capillary wedge pressure (CWP) while E velocity correlated significantly with CWP (R² = 0.29, p = 0.0007). Among 38 patients in sinus rhythm, echocardiographic diastolic dysfunction strongly correlated with elevated LA pressure in RHC (CWP ≥ 12 mmHg, p = 0.001), with 96% sensitivity and 80% specificity. LA minimal volume index (LAVmin-i) as measured by echocardiogram was significantly correlated with elevated LA pressure in RHC (p = 0.04, criterion ≥ 27 ml) regardless of rhythm.

Conclusions

In patients with sinus rhythm, diastolic dysfunction was found to be sensitive and specific for elevated CWP ≥ 12 mmHg at RHC. In all patients regardless of rhythm, LAVmin-i was found to correlate best with elevated LA pressure at RHC. This may suggest a new tool for assessment of diastolic dysfunction in all subjects.

Comparing echocardiographic characteristics in genotype positive-phenotype positive hypertrophic cardiomyopathy and hypertensive left ventricular hypertrophy

AIMS

There is little information about hypertrophic cardiomyopathy (HCM) with pathologic genetic mutations and concurrent hypertension (HTN). Hypertensive left ventricular hypertrophy (LVH) does not exclude an underlying genetic aetiology.

METHODS AND RESULTS

This was a single-centre case-control study of 39 adults with pathologic HCM mutations, confirmed by genetic testing, compared to 39 age- and gender-matched patients with hypertensive LVH. The gene-positive HCM cohort was further stratified by the coexisting presence or absence of HTN. Clinical and echocardiographic characteristics were compared. Of 39 gene-positive HCM, 43.6% (17/39) had concurrent HTN. The gene-positive HCM cohort had larger left atrial (LA) area (22.1 cm2 vs. 18.9 cm2, P = 0.002), more diastolic predominant pulmonary vein flow (38.5% vs. 7.7%, P = 0.001), and more moderate diastolic dysfunction (33.3% vs. 12.8%, P = 0.032) when compared with the hypertensive LVH cohort. Greater left ventricular (LV) mass (277.7 g vs. 207.7 g, P = 0.025), increased frequency of severe LVH (58.8% vs. 27.3%, P = 0.047), and more abnormal global longitudinal strain (GLS) (-14.1% vs. -16.9%, P = 0.049) was observed in the gene-positive HCM cohort with concurrent HTN.

CONCLUSION

Gene-positive HCM, compared to hypertensive LVH, is characterized by more advanced diastolic dysfunction and larger LA size. Gene-positive HCM patients with concomitant HTN had greater LV mass, more severe LVH, and more abnormal GLS, suggesting HTN may negatively affect the progression of myocardial dysfunction in genetic HCM. LVH out-of-proportion to pressure burden in HTN patients should raise suspicion of underlying genetic HCM.

Impact of Prosthesis-Patient Mismatch on Hemodynamics During Exercise in Patients With Aortic Stenosis After Transcatheter Aortic Valve Implantation With a Balloon-Expandable Valve

Background

There is no evidence of hemodynamic performance during exercise in patients with aortic stenosis (AS) after transcatheter aortic valve implantation (TAVI). This study aimed to investigate the changes in kinematic hemodynamics during exercise and determine the impact of prosthesis-patient mismatch (PPM) on the hemodynamics of transcatheter heart valves using exercise stress echocardiography (ESE) in AS patients after TAVI.

Methods and Results

This study enrolled 77 consecutive patients (mean age 82 ± 5 years, 50.6% male) who underwent ESE 3–6 months after TAVI with a balloon-expandable valve. The effective orifice area index at rest was significantly correlated with the mean pressure gradient (PG) during exercise (p <0.001). The patients were divided into two groups according to the presence of PPM (PPM and non-PPM groups). During exercise, the patients with PPM had a higher left ventricular ejection fraction (74.6 ± 6.1% vs. 69.7 ± 9.6%, p = 0.048), a lower stroke volume index (47.2 ± 14.0 ml/m² vs. 55.6 ± 14.5 ml/m², p = 0.037), a significantly higher mean transvalvular PG (21.9 ± 9.1 mmHg vs. 12.2 ± 4.9 mmHg, p = 0.01) and an increased mean PG from rest to exercise (5.7 ± 3.5 mmHg vs. 2.3 ± 2.8 mmHg, p <0.001) compared with patients without PPM. Patients with PPM had a higher pulmonary artery systolic pressure (SPAP) during exercise (57.3 ± 13.8 mmHg vs. 49.7 ± 10.9 mmHg, p = 0.021) and a higher incidence of exercise-induced pulmonary hypertension (43.8 vs. 15.0%, p = 0.037) than patients without PPM. PPM was strongly associated with exercise-induced pulmonary hypertension (hazard ratio: 3.570, p = 0.013).

Conclusions

AS patients with PPM after TAVI showed a disproportionate increase in the transvalvular PG and SPAP during exercise, and PPM was associated with exercise-induced pulmonary hypertension.

Major Clinical Issues in Hypertrophic Cardiomyopathy

By actively implementing contemporary management strategies in hypertrophic cardiomyopathy, morbidity and mortality can be substantially reduced. In this review, we discuss the pathophysiology and management of the major clinical issues in hypertrophic cardiomyopathy, including sudden cardiac death, atrial fibrillation and thromboembolism, dynamic left ventricular outflow tract obstruction, and heart failure progression. Although echocardiography and cardiac magnetic resonance imaging currently play an essential and complementary role in the management of hypertrophic cardiomyopathy, further studies are needed to establish how developing techniques such as myocardial deformation and late gadolinium enhancement can provide better risk stratification and guide treatment.

Hypertrophic cardiomyopathy (HCM) is one of the most common inheritable cardiomyopathies. Contemporary management strategies, including the advent of implantable cardioverter-defibrillators and effective anticoagulation, have substantially improved the clinical course of HCM patients; however, the disease burden of HCM is still high in Korea. Sudden cardiac death (SCD), atrial fibrillation and thromboembolic risk, dynamic left ventricular outflow tract (LVOT) obstruction, and heart failure (HF) progression remain important issues in HCM. SCD in HCM can be effectively prevented with implantable cardioverter-defibrillators. However, appropriate patient selection is important for primary prevention, and the 5-year SCD risk score and the presence of major SCD risk factors should be considered. Anticoagulation should be initiated in all HCM patients with atrial fibrillation regardless of the CHA₂DS₂-VASc score, and non-vitamin K antagonist oral anticoagulants are the first option. Symptomatic dynamic LVOT obstruction is first treated medically with negative inotropes, and if symptoms persist, septal reduction therapy is considered. The recently approved myosin inhibitor mavacamten is promising. HF in HCM is usually related to diastolic dysfunction, while about 5% of HCM patients show reduced left ventricular ejection fraction <50%, also referred to as “end-stage” HCM. Myocardial fibrosis plays an important role in the progression to advanced HF in patients with HCM. Patients who do not respond to guideline-directed medical therapy can be considered for heart transplantation. The development of imaging techniques, such as myocardial deformation on echocardiography and late gadolinium enhancement on cardiac magnetic resonance, can provide better risk evaluation and decision-making for management strategies in HCM.

Sex related differences in exercise performance in patients with hypertrophic cardiomyopathy: Hemodynamic insights through non-invasive pressure volume analysis

BACKGROUND

Women with HCM have worse cardiopulmonary exercise performance compared to men. We used non-invasive pressure-volume (PV) analysis to delineate sex related hemodynamic differences in HCM.

METHODS

PV loops were constructed from echocardiograms using left ventricular (LV) volumes indexed to body surface area, Doppler estimates of LV end-diastolic pressure and blood pressure. The end-systolic PV relationship (ESPVR) and end-diastolic PV relationship (EDPVR) were derived from validated single-beat techniques. The area between the ESPVR and EDPVR (isovolumetric PV area), was indexed to an LV end-diastolic pressure of 30 mmHg (PVA_iso30), as the integrated metric of LV function. LV volume at an end-diastolic pressure of 30 mmHg (V30) indexed ventricular capacity.

RESULTS

202 patients were included, 56 women. Women were older (51 vs 44 years, p = 0.012) and had reduced exercise capacity (5.6 vs 6.9 METs, p < 0.001). Only 32 patients (16%) had a peak gradient >30 mmHg at rest with no sex differences. Women had significantly lower indexed PVA_iso30 (9094 vs 10,255 mmHg*mL/m², p = 0.02) driven by reduced ventricular capacitance (V30 54 vs 62 mL/m², p < 0.001). In multivariable linear regression indexed V30 was an independent predictor of exercise capacity.

CONCLUSION

Impaired exercise capacity in women with HCM appears associated with abnormalities in passive diastolic properties, suggesting a unique pathophysiology compared to men, and a potential difference in viable therapeutic molecular targets.

Impact of Afterload-Integrated Diastolic Indexon Prognosis in Elderly Patients with Heart Failure with Preserved Ejection Fraction with and without Atrial Fibrillation

Objects

We aimed to clarify the differences in the of the ratio of diastolic elastance (Ed) to arterial elastance (Ea), [Ed/Ea=(E/e')/(0.9×systolic blood pressure)], anafterload-integrateddiastolic index that reflects left atrial pressure overload, on prognosis between patients with heart failure with preserved ejection fraction (HFpEF) with and without atrial fibrillation (AF).

Methods

We studied 552 HFpEF patients hospitalized for acute decompensated heart failure (sinus rhythm/AF:352/200).Blood testing and transthoracic echocardiography were performed before discharge. Primary endpoint was all-cause mortality after discharge.

Results

During a median follow-up of 508 days, 88 patients (sinus rhythm/AF: 54/34) had all-cause mortality. In the subgroup with sinus rhythm, but not AF, Ed/Ea was significantly higher in patients with than without all-cause mortality. In a multivariate Cox hazard analysis, Ed/Ea was significantly associated with all-cause mortality independent of N-terminal pro-brain natriuretic peptide level in patients with sinus rhythm, but not with AF.

Conclusions

Ed/Ea providedlesser important information for predicting all-cause mortality in HFpEF patients with AF than with sinus rhythm. The prognostic risk factors may differ between elderly HFpEF patients with and without AF.

Left atrial pressure overload and prognosis in elderly patients with heart failure and preserved ejection fraction: a prospective multicenter observational study

OBJECTIVES

The severity of diastolic dysfunction is assessed using a combination of several indices of left atrial (LA) volume overload and LA pressure overload. We aimed to clarify which overload is more associated with the prognosis in patients with heart failure and preserved ejection fraction (HFpEF).

SETTING

A prospective, multicenter observational registry of collaborating hospitals in Osaka, Japan.

PARTICIPANTS

We enrolled hospitalised patients with HFpEF showing sinus rhythm (men, 79; women, 113). Blood tests and transthoracic echocardiography were performed before discharge. The ratio of diastolic elastance (Ed) to arterial elastance (Ea) was used as a relative index of LA pressure overload.

PRIMARY OUTCOME MEASURES

All-cause mortality and admission for heart failure were evaluated at >1 year after discharge.

RESULTS

In the multivariable Cox regression analysis, Ed/Ea, but not LA volume index, was significantly associated with all-cause mortality or admission for heart failure (HR 2.034, 95% CI 1.059 to 3.907, p=0.032), independent of age, sex, and the serum N-terminal pro-brain natriuretic peptide (NT-proBNP) level. In patients with a higher NT-proBNP level, the effect of higher Ed/Ea on prognosis was prominent (p=0.015).

CONCLUSIONS

Ed/Ea, an index of LA pressure overload, was significantly associated with the prognosis in elderly patients with HFpEF showing sinus rhythm.

TRIAL REGISTRATION NUMBER

UMIN000021831.

The Association between the Extent of Late Gadolinium Enhancement and Diastolic Dysfunction in Hypertrophic Cardiomyopathy

Background Diastolic dysfunction in hypertrophic cardiomyopathy (HCM) patients is a frequent, yet poorly understood phenomenon.

Purpose The purpose of this study is to assess the relationship between the myocardial fibrosis and diastolic dysfunction in patients with HCM.

Materials and Methods We retrospectively investigated the impact of the myocardial fibrosis, as assessed by the extent of late gadolinium enhancement (LGE-%) on cardiac magnetic resonance imaging (CMRI), on diastolic dysfunction in 110 patients with HCM. The diastolic dysfunction was evaluated by the left atrial (LA) volume index measured on CMRI and lateral septal E/E′ ratio calculated on echocardiography.

Results : There was a moderate correlation between the LGE-% and LA volume ( r = 0.59, p < 0.0001). The logistic regression model of LGE-%, mitral regurgitation, and total left ventricular mass that investigated the independent predictors of LA volume identified LGE-% as the only independent parameter associated with the LA volume index ( β = 0.30, p = 0.003). No correlation was observed between the LGE-% and E/E′( r = 0.24, p = 0.009).

Conclusions Myocardial fibrosis in HCM patients is associated with a chronic diastolic burden as represented by increased LA volume. However, the fibrosis does not influence the E/E′ ratio, which is a well-known parameter of ventricular relaxation, restoring forces, and filling pressure.

Impact of septal myectomy on diastolic function in patients with obstructive hypertrophic cardiomyopathy

Background

The impact of septal myectomy on diastolic function in patients with obstructive hypertrophic cardiomyopathy is not well studied.

Methods

A transcatheter hemodynamic study was performed before and 3 to 6 months after septal myectomy in 12 patients with obstructive hypertrophic cardiomyopathy (HCM).

Results

Postoperative hemodynamic studies were done 4.4±1.2 months after myectomy. The left ventricular outflow tract peak-to-peak gradient decreased from 83.2±43.3 mmHg preoperatively to 11.6±4.3 mmHg after myectomy (P<0.00). The left ventricular diastolic time constant (Tau) was 64.2±26.1 ms before surgery and 42.2±15.7 ms postoperatively (P=0.029). The average left atrial pressure (LAP) decreased from 20.2±7.0 to 12.1±4.5 mmHg after myectomy (P=0.008). Pulmonary artery hypertension was present in 6 patients preoperatively and remained in 2 patients after myectomy. Mean pulmonary artery pressure decreased from 29.3±16.2 to 20±6.7 mmHg after surgery (P=0.05), and the systolic pulmonary artery pressure decreased from 46±26.9 to 30.5±8.3 mmHg (P=0.048). Pulmonary vascular resistance decreased from 5.7±4.1 to 3.6±1.6 wood after surgery (P=0.032).

Conclusions

Septal myectomy improved left ventricular diastolic function and subsequently relieved the right ventricular congestion in patients with obstructive HCM.

Cardiomyopathies: An Overview

Background: Cardiomyopathies are a heterogeneous group of pathologies characterized by structural and functional alterations of the heart. Aims: The purpose of this narrative review is to focus on the most important cardiomyopathies and their epidemiology, diagnosis, and management. Methods: Clinical trials were identified by Pubmed until 30 March 2021. The search keywords were “cardiomyopathies, sudden cardiac arrest, dilated cardiomyopathy (DCM), hypertrophic cardiomyopathy (HCM), restrictive cardiomyopathy, arrhythmogenic cardiomyopathy (ARCV), takotsubo syndrome”. Results: Hypertrophic cardiomyopathy (HCM) is the most common primary cardiomyopathy, with a prevalence of 1:500 persons. Dilated cardiomyopathy (DCM) has a prevalence of 1:2500 and is the leading indication for heart transplantation. Restrictive cardiomyopathy (RCM) is the least common of the major cardiomyopathies, representing 2% to 5% of cases. Arrhythmogenic cardiomyopathy (ARCV) is a pathology characterized by the substitution of the myocardium by fibrofatty tissue. Takotsubo cardiomyopathy is defined as an abrupt onset of left ventricular dysfunction in response to severe emotional or physiologic stress. Conclusion: In particular, it has been reported that HCM is the most important cause of sudden death on the athletic field in the United States. It is needless to say how important it is to know which changes in the heart due to physical activity are normal, and when they are pathological.

Personalized monitoring of electrical remodelling during atrial fibrillation progression via remote transmissions from implantable devices

Aims

Atrial electrical remodelling (AER) is a transitional period associated with the progression and long-term maintenance of atrial fibrillation (AF). We aimed to study the progression of AER in individual patients with implantable devices and AF episodes.

Methods and results

Observational multicentre study (51 centres) including 4618 patients with implantable cardioverter-defibrillator +/−resynchronization therapy (ICD/CRT-D) and 352 patients (2 centres) with pacemakers (median follow-up: 3.4 years). Atrial activation rate (AAR) was quantified as the frequency of the dominant peak in the signal spectrum of AF episodes with atrial bipolar electrograms. Patients with complete progression of AER, from paroxysmal AF episodes to electrically remodelled persistent AF, were used to depict patient-specific AER slopes. A total of 34 712 AF tracings from 830 patients (87 with pacemakers) were suitable for the study. Complete progression of AER was documented in 216 patients (16 with pacemakers). Patients with persistent AF after completion of AER showed ∼30% faster AAR than patients with paroxysmal AF. The slope of AAR changes during AF progression revealed patient-specific patterns that correlated with the time-to-completion of AER (R² = 0.85). Pacemaker patients were older than patients with ICD/CRT-Ds (78.3 vs. 67.2 year olds, respectively, P < 0.001) and had a shorter median time-to-completion of AER (24.9 vs. 93.5 days, respectively, P = 0.016). Remote transmissions in patients with ICD/CRT-D devices enabled the estimation of the time-to-completion of AER using the predicted slope of AAR changes from initiation to completion of electrical remodelling (R² = 0.45).

Conclusion

The AF progression shows patient-specific patterns of AER, which can be estimated using available remote-monitoring technology.

Pulmonary blood volume index as a quantitative biomarker of haemodynamic congestion in hypertrophic cardiomyopathy

Aims 

The non-invasive assessment of left ventricular (LV) diastolic function and filling pressure in hypertrophic cardiomyopathy (HCM) is still an open issue. Pulmonary blood volume index (PBVI) by cardiovascular magnetic resonance (CMR) has been proposed as a quantitative biomarker of haemodynamic congestion. We aimed to assess the diagnostic accuracy of PBVI for left atrial pressure (LAP) estimation in patients with HCM.

Methods and results 

We retrospectively identified 69 consecutive HCM outpatients (age 58 ± 11 years; 83% men) who underwent both transthoracic echocardiography (TTE) and CMR. Guideline-based detection of LV diastolic dysfunction was assessed by TTE, blinded to CMR results. PBVI was calculated as the product of right ventricular stroke volume index and the number of cardiac cycles for a bolus of gadolinium to pass through the pulmonary circulation as assessed by first-pass perfusion imaging. Compared to patients with normal LAP, patients with increased LAP showed significantly larger PBVI (463 ± 127 vs. 310 ± 86 mL/m², P < 0.001). PBVI increased progressively with worsening New York Heart Association functional class and echocardiographic stages of diastolic dysfunction (P < 0.001 for both). At the best cut-off point of 413 mL/m², PBVI yielded good diagnostic accuracy for the diagnosis of LV diastolic dysfunction with increased LAP [C-statistic = 0.83; 95% confidence interval (CI): 0.73–0.94]. At multivariable logistic regression analysis, PBVI was an independent predictor of increased LAP (odds ratio per 10% increase: 1.97, 95% CI: 1.06–3.68; P = 0.03).

Conclusion 

PBVI is a promising CMR application for assessment of diastolic function and LAP in patients with HCM and may serve as a quantitative marker for detection, grading, and monitoring of haemodynamic congestion.

Novel Estimation of Left Ventricular Filling Pressure Using 3-D Speckle-Tracking Echocardiography: Assessment in a Decompensated Systolic Heart Failure Model

E/e' allows for the non-invasive estimation of left ventricular (LV) filling pressure; however, Doppler malalignment can make the estimation unreliable, especially in dilated systolic failing hearts. The ratio of peak early diastolic filling rate to peak early diastolic global strain rate (FRe/SRe), which is a parameter derived from 3-D speckle-tracking echocardiography to estimate filling pressure, may be better applied in dilated systolic failing hearts because it can be obtained without the Doppler method. We investigated whether FRe/SRe could provide a better estimation of filling pressure than E/e' in 23 dogs with decompensated systolic heart failure induced by microembolization. FRe/SRe had better correlation coefficients with LV end-diastolic pressure (0.75-0.90) than did E/e' (0.40). The diagnostic accuracy of FRe/SRe in distinguishing elevated filling pressure was significantly higher than that of E/e'. This study indicates that FRe/SRe may provide a better estimation of LV filling pressure than E/e' in dilated systolic failing hearts.

Diagnostic value of left atrial strain in pediatric hypertrophic cardiomyopathy with normal maximum left atrial volume index: preliminary cardiac magnetic resonance study

BACKGROUND

The maximum left atrial volume index is the most widely used metric for assessing the left atrium in hypertrophic cardiomyopathy; however, it may be normal in the early phases of the disease.

OBJECTIVE

To assess whether pediatric hypertrophic cardiomyopathy patients with normal maximum left atrial volume index have impaired atrial functions on cardiac magnetic resonance imaging (MRI).

MATERIALS AND METHOD

A total of 26 pediatric hypertrophic cardiomyopathy patients and 24 age-matched children, as controls, were enrolled in the study. The left atrial reservoir, conduit and booster strain were calculated from two orthogonal planes and the left atrial volumes were calculated using the biplanar method. The extent of left ventricular late gadolinium enhancement (LGE-%) was calculated using the thresholding method. The left ventricular early diastolic longitudinal strain rate was calculated to assess diastolic dysfunction.

RESULTS

The maximum left atrial volume index of the children with hypertrophic cardiomyopathy and the controls were not significantly different (P>0.05). Most of the left atrial functional indices were worse in children with hypertrophic cardiomyopathy (P<0.05), yet no difference was observed between the left atrial booster strains of the two groups (P>0.05). The left atrial conduit strain showed moderate to good negative correlations with left ventricular LGE-% and diastolic dysfunction.

CONCLUSION

Left atrial conduit and reservoir strains are impaired in pediatric hypertrophic cardiomyopathy patients with normal maximum left atrial volumetric indices. Most left atrial strain parameters are closely linked to left ventricular LGE-% and diastolic dysfunction. Left atrial strain analysis may reveal subtle functional changes in the atrium before the increase in the maximum volume index.

Prognostic value of fast semi-automated left atrial long-axis strain analysis in hypertrophic cardiomyopathy

BACKGROUND

The prognostic value of left atrial (LA) size and function in hypertrophic cardiomyopathy (HCM) is well recognized, but LA function is difficult to routinely analyze. Fast LA long-axis strain (LA-LAS) analysis is a novel technique to assess LA function on cine cardiovascular magnetic resonance (CMR). We aimed to assess the association between fast LA-LAS and adverse clinical outcomes in patients with HCM.

METHODS

359 HCM patients and 100 healthy controls underwent routine CMR imaging. Fast LA-LAS was analyzed by automatically tracking the length between the midpoint of posterior LA wall and the left atrioventricular junction based on standard 2- and 4-chamber balanced steady-state free precession cine-CMR. Three strain parameters including reservoir strain (εs), conduit strain (εe), and active strain (εa) were assessed. The endpoint was set as composite adverse events including cardiovascular death, resuscitated cardiac arrest, sudden cardiac death aborted by appropriate implantable cardioverter-defibrillator discharge, and hospital admission related to heart failure.

RESULTS

During an average follow-up of 40.9 months, 59 patients (19.7%) reached endpoints. LA strains were correlated with LA diameter, LA volume index (LAVI) and LA empty fraction (LAEF) (all p < 0.05). In the stepwise multivariate Cox regression analysis, εs and εe (hazard ratio, 0.94 and 0.89; p = 0.019 and 0.006, respectively) emerged as independent predictors of the composite adverse events. Fast LA εs and LA εe are stronger prognostic factors than LA size, LAVI and the presence of left ventricular late gadolinium enhancement.

CONCLUSIONS

Fast LA reservoir and conduit strains are independently associated with adverse outcomes in HCM.

Tissue Doppler Imaging (E/e') and Pulmonary Capillary Wedge Pressure in Patients With Severe Aortic Stenosis

OBJECTIVE

Although American and European consensus statements advocate using the ratio of the transmitral E velocity and tissue Doppler early diastolic mitral annular velocity (E/e') in the assessment of left-sided heart filling pressures, recent reports have questioned the reliability of this ratio to predict left atrial pressures in a variety of disease states. The authors hypothesized that there is a clinically significant correlation between E/e' and pulmonary capillary wedge pressure (PCWP) in patients with severe aortic stenosis.

DESIGN

Retrospective cohort study.

PARTICIPANTS

The study comprised 733 consecutive patients with severe aortic stenosis who underwent transcatheter aortic valve replacement for severe aortic stenosis.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

PCWP and E/e'_ave (average of the lateral and medial annulus tissue Doppler velocities) were measured with a pulmonary artery catheter and transthoracic echocardiography during preprocedural evaluation. Patients were grouped by left ventricular ejection fraction (LVEF) ≥50% and LVEF <50%. Spearman rank correlation, analysis of variance, and t and chi-square tests were used to analyze the data. Seventy-nine patients met the inclusion criteria. There was no significant correlation between E/e'_ave and PCWP (n = 79, Spearman r = 0.096; p = 0.3994). This correlation did not improve when ventricular function was considered (LVEF <50%: n = 11, Spearman r = -0.097; p = 0.776 and LVEF ≥50%: n = 68, Spearman r = 0.116; p = 0.345). There was no statistically significant difference in mean PCWP between each range of E/e'_ave.

CONCLUSION

A clinically relevant relationship between E/e' and PCWP was not observed in patients with severe aortic stenosis.

Sex, racial differences and healthy aging in normative reference ranges on diastolic function in Ethnic Asians: 2016 ASE guideline revisited

BACKGROUND

Diastolic dysfunction (DD) has shown to be a hallmark pathological intermediate in the development of heart failure with preserved ejection fraction (HFpEF). We aim to establish age- and sex-stratified normal reference values of diastolic indices and to explore racial-differences.

METHODS

We explored age- and sex-related structural/functional alterations from 6023 healthy ethnic Asians (47.1 ± 10.9 years, 61.3% men) according to 2016 American Society of Echocardiography (ASE) diastolic dysfunction (DD) criteria. Racial comparisons were made using data from London Life Sciences Prospective Population (LOLIPOP) study.

RESULTS

Age- and sex-based normative ranges (including mean, median, 10% and 90% lower and upper reference values) were extracted from our large healthy population. In fully adjusted models, advanced age was independently associated with cardiac structural remodeling and worsened diastolic parameters including larger indexed LA volume (LAVi), lower e', higher E/e', and higher TR velocity; all p < 0.001), which were more prominent in women (P interaction: <0.05). Broadly, markedly lower e', higher E/e' and smaller LAVi were observed in ethnic Asians compared to Whites. DD defined by 2016 ASE criteria, despite at low prevalence (0.42%) in current healthy population, increased drastically with advanced age and performed perfectly in excluding abnormal NT-proBNP (≥125 pg/mL) (Specificity: 99.8%, NPV: 97.6%).

CONCLUSION

This is to date the largest cohort exploring the normative reference values using guideline-centered diastolic parameters from healthy Asians, with aging played as central role in diastolic dysfunction. Our observed sex and ethnic differences in defining healthy diastolic cut-offs likely impact future clinical definition for DD in Asians.

Assessment of atrial function by myocardial deformation techniques in hypertrophic cardiomyopathy

BACKGROUND

Diastolic dysfunction in hypertrophic cardiomyopathy (HCM) is common, but its assessment is difficult using conventional echocardiography.

AIMS

To assess left atrial (LA) function in HCM by longitudinal strain and determine its role in understanding of symptoms.

METHODS

We studied 144 patients divided into 3 age- and sex-matched groups: 48 consecutive patients with HCM, 48 control subjects, and 48 athlete subjects. We assessed LA function by conventional echocardiographic parameters and by longitudinal atrial strain (early-diastolic left atrial strain during reservoir phase [LASr]; end-diastolic left atrial strain during conduit phase; end-systolic peak of the left atrial strain during contraction phase).

RESULTS

NYHA classification was as follows in HCM group: I in 46%, II in 31%, III in 19%, and IV in 4%. Conventional echocardiographic parameters of diastolic function were depressed in the HCM group as compared to the control and athlete groups, but not related to symptoms. All longitudinal atrial strain parameters were significantly reduced in HCM group as compared to two groups (P < .0001). LASr was significantly correlated to peak VO2 (r = 0.44, P = .01) and was the best parameter for detecting symptomatic patients presenting with HCM, with a cutoff value of 15%: Sensitivity was 71%, specificity was 79%, PPV was 77%, and NPV was 73%.

CONCLUSION

Assessment of LA function in HCM is feasible using longitudinal strain, and this technique is more reliable than conventional echocardiographic parameters for the understanding of determinants of symptoms.

2020 AHA/ACC Guideline for the Diagnosis and Treatment of Patients With Hypertrophic Cardiomyopathy: Executive Summary: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

AIM

This executive summary of the hypertrophic cardiomyopathy clinical practice guideline provides recommendations and algorithms for clinicians to diagnose and manage hypertrophic cardiomyopathy in adult and pediatric patients as well as supporting documentation to encourage their use.

METHODS

A comprehensive literature search was conducted from January 1, 2010, to April 30, 2020, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Collaboration, Agency for Healthcare Research and Quality reports, and other relevant databases.

STRUCTURE

Many recommendations from the earlier hypertrophic cardiomyopathy guidelines have been updated with new evidence or a better understanding of earlier evidence. This summary operationalizes the recommendations from the full guideline and presents a combination of diagnostic work-up, genetic and family screening, risk stratification approaches, lifestyle modifications, surgical and catheter interventions, and medications that constitute components of guideline directed medical therapy. For both guideline-directed medical therapy and other recommended drug treatment regimens, the reader is advised to follow dosing, contraindications and drug-drug interactions based on product insert materials.

2020 AHA/ACC Guideline for the Diagnosis and Treatment of Patients With Hypertrophic Cardiomyopathy: Executive Summary: A Report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines

Aim This executive summary of the hypertrophic cardiomyopathy clinical practice guideline provides recommendations and algorithms for clinicians to diagnose and manage hypertrophic cardiomyopathy in adult and pediatric patients as well as supporting documentation to encourage their use. Methods A comprehensive literature search was conducted from January 1, 2010, to April 30, 2020, encompassing studies, reviews, and other evidence conducted on human subjects that were published in English from PubMed, EMBASE, the Cochrane Collaboration, Agency for Healthcare Research and Quality reports, and other relevant databases. Structure Many recommendations from the earlier hypertrophic cardiomyopathy guidelines have been updated with new evidence or a better understanding of earlier evidence. This summary operationalizes the recommendations from the full guideline and presents a combination of diagnostic work-up, genetic and family screening, risk stratification approaches, lifestyle modifications, surgical and catheter interventions, and medications that constitute components of guideline directed medical therapy. For both guideline-directed medical therapy and other recommended drug treatment regimens, the reader is advised to follow dosing, contraindications and drug-drug interactions based on product insert materials.