Reference Values for Physical Stress Echocardiography in Asymptomatic Patients after Mitral Valve Repair.

BACKGROUND: Clinical decision-making in symptomatic patients after mitral valve (MV) repair remains challenging as echocardiographic reference values are lacking. In native MV disease intervention is recommended for mean transmitral pressure gradient (TPG) >15 mmHg or systolic pulmonary artery pressure (SPAP) >60 mmHg at peak exercise. Insight into standard stress echo parameters after MV repair may therefore aid to clinical decision-making during follow-up. HYPOTHESIS: Stress echocardiography derived parameters in asymptomatic patients after successful MV repair differ from current guidelines for native valves. MATERIAL AND METHODS: In 25 patients (NYHA I) after MV repair stress echocardiography was performed on a semi-supine bicycle. Doppler flow records and MV related hemodynamics at rest and peak were obtained. Linear regression analysis was performed for mean TPG and SPAP at peak, using predetermined variables and confounders. RESULTS: Mean TPG at rest (3.2 ± 1.4 mmHg) significantly increased at peak (15.0 ± 3.4 mmHg) but was always <25 mmHg. Mean SPAP at rest (21.4 ± 3.8 mmHg) significantly increased at peak (41.8 ± 8.9 mmHg) but was never >57 mmHg. Only the indexed MV ring diameter was inversely correlated to mean TPG at peak in a multivariable model. CONCLUSION: In contrast to current recommendations in native MV disease, our data indicate that the standard value for mean TPG during stress echocardiography in asymptomatic patients after successful MV repair was above the guideline threshold of 15 mmHg in >50%, but always <25 mmHg. For SPAP, patients never reached the guideline cutoff (60 mmHg). Long-term follow-up data are needed to provide insight in clinical consequences. Baseline stress echocardiography may indicate individual reference values to compare with during follow-up. CLINICAL TRIAL REGISTRATION: https://clinicaltrials.gov/ct2/show/NCT02371863?term=chamuleau+AND+Mitral&rank=1.

An easy-to-use scoring index to determine severity of mitral regurgitation by 2D echocardiography in clinical practice.

PURPOSE: Mitral regurgitation (MR) grading by two-dimensional transthoracic echocardiography is challenging, but important to determine the best treatment strategy in patients with MR. Current guidelines advocate an integrative approach, although no recommendation is provided on how to do so. An easy-to-use index will be helpful for standardized and reproducible MR grading. METHODS: Eleven echocardiographic parameters were retrospectively evaluated in 145 patients with moderate or severe MR. Parameters were scored positive or negative for severe MR, where expert panel consensus reading was considered as the reference standard. Logistic regression was performed, and adjusted coefficients were used to create a risk score for severe MR per patient (ROSE-index). The best cutoff with corresponding predictive values was determined. RESULTS: Eighty-two percent of all parameters could be determined. Multivariable analysis revealed five parameters that remained significant predictors for severe MR: morphology, jet characteristics, vena contracta, systolic reversal, and left ventricular dimensions. With different weighing, a total score of 8 could be obtained. Median total ROSE-index score for moderate (2.0) and severe MR (5.0) did significantly differ. The cutoff score (≥4) revealed sensitivity 0.84 and specificity 0.83 to diagnose severe MR. Negative predictive value was 100% for score 0 and 1; score 6-8 showed a 100% positive predictive value. Inter- and intra-observer agreements were excellent (K-values >0.80). CONCLUSION: Here, we propose an easy-to-use tool for integrated analysis of guideline parameters to assess MR severity. Using this so-called ROSE-index revealed reliable and reproducible assessment of severe MR (cutoff≥4) that may be helpful for clinical decision making.

Non-invasive measurement of volume-time curves in patients with mitral regurgitation and in healthy volunteers, using a new operator-independent screening tool.

Left ventricular volume-time curves (VTCs) provide hemodynamic data, and may help clinical decision making. The generation of VTCs using echocardiography, however, is time-consuming and prone to inter-operator variability. In this study, we used a new non-invasive, operator-independent technique, the hemodynamic cardiac profiler (HCP), to generate VTCs. The HCP, which uses a low-intensity, patient-safe, high-frequency applied AC current, and 12 standard ECG electrodes attached on the thorax in a pre-defined pattern, was applied to five young healthy volunteers, five older healthy volunteers, and five patients with severe mitral regurgitation. From the VTCs generated by the HCP, the presence or absence of an isovolumetric contraction phase (ICP) was assessed, as well as the left ventricular ejection time (LVET), time of the pre-ejection period (tPEP), and ratio of the volumes of the early (E) and late (A) diastolic filling (E V/A V ratio), and compared to 2D transthoracic echocardiography (2D TTE) at rest. The reproducibility by two different operators showed good results (RMS = 5.2%). For intra-patient measurement RMS was 2.8%. Both LVET and the E V/A V ratio showed a strong significant correlation between HCP and 2D TTE derived parameters (p < 0.05). For tPEP, the correlation was still weak (p = 0.32). In all five patients with mitral regurgitation, the ICP was absent in the VTC from the HCP, whereas it was present in the 10 healthy volunteers, which is in accordance with pathophysiology. We conclude that the HCP seems to be a method for reproducible VTC generation, and may become a useful early screening tool for cardiac dysfunction in the future.

Identification of the Asymptomatic Patient With Severe Mitral Regurgitation: Discrepancy Between Research and Clinical Practice.

Organic mitral regurgitation (MR) is a common disorder, and because of the increase in population and its aging, the occurrence of MR is steadily increasing. Current guideline recommendations on the management of asymptomatic severe MR are conflicting and based solely on registries or nonrandomized trials in expert heart valve clinics, resulting in a lack of evidence for the best treatment strategy. In this review, we will evaluate the latest evidence on diagnostic approaches and treatment strategies for asymptomatic patients without a clear indication for surgical intervention. Implications for management in daily practice are discussed, including an update on the diagnostic approaches that are currently available for the evaluation of MR. For optimal care, it is important that every severe MR patient, including the unidentified patient, is referred to a specialized heart team and is assessed on an individual basis according to the guideline recommendations, experience of the surgical center, and the patient's characteristics and preferences. Screening and diagnostic approaches need to be performed on the basis of standardized protocols and strict criteria. In addition, specialized valve centers must meet the surgical criteria to guarantee high reparability rates in asymptomatic patients. Awareness among cardiologists and cardiothoracic surgeons, improved guidelines adherence, and a systematic approach, including strict criteria in the management of asymptomatic patients with severe organic MR, will ensure reliable and applicable results in research and daily clinical practice.

[Diagnostic and therapeutic strategies for the management of severe mitral valve regurgitation]. / Mitralisklepinsufficiëntie: het lek te lijf: diagnostiek en behandeling.

Mitral regurgitation is the second most frequent valvular heart disease. Echocardiography is the principal examination to determine severity, mechanism and hemodynamic consequences of mitral regurgitation and consequently contributes to the assessment and accurate timing of the best treatment strategy. To clarify clinical decision making in severe mitral regurgitation, this review will discuss the diagnostic work-up and treatment options according to the most recent guidelines. Mitral valve surgery, preferably repair, is indicated in symptomatic patients with severe, organic mitral regurgitation. Chronic, functional mitral regurgitation is often medically treated (including cardiac resynchronization therapy if indicated), however surgery (preferably annuloplasty) can be recommended. Percutaneous MitraClip-implantation may be considered as an alternative option in symptomatic patients with severe mitral regurgitation who are considered inoperable. At present, there is no consensus on the optimal care in asymptomatic patients with severe, organic mitral regurgitation and preserved left ventricular function. A prospective trial is highly needed to elucidate this best treatment strategy.