The role of exercise echocardiography in the management of mitral valve disease

Prognostic impact of vasopressor test in transcatheter edge-to-edge repair of secondary mitral regurgitation: The PETIT study

BACKGROUND

Vasopressor test (VPT) might be useful in patients with functional mitral regurgitation (MR) and left ventricular dysfunction (MITRA-FR-like patients) during transcatheter edge-to-edge repair (TEER).

AIMS

We aimed to evaluate the prognostic impact of VPT.

METHODS

MR treated with TEER were included in a multicenter prospective registry. VPT was used intraprocedurally in patients with left ventricular dysfunction and/or hypotension. The 1-year echocardiographic and clinical outcomes were compared according to the use of VPT. The primary endpoint was a combination of mortality + heart failure (HF) readmission at 1-year.

RESULTS

A total of 1115 patients were included, mean age was 72.8 ± 10.5 years and 30.4% were women. VPT was performed in 128 subjects (11.5%), more often in critically ill patients with biventricular dysfunction. Postprocedurally the VPT group had greater rate of MR ≥ 2+ (46.9% vs. 31.7%, p = 0.003) despite greater number of devices (≥2 clips, 52% vs. 40.6 p = 0.008) and device repositioning or new clip in 12.5%. At 1-year, the primary endpoint occurred more often in the VPT group (27.3% vs. 16.9%, p = 0.002) as well as all-cause mortality (21.9% vs. 8.1%, p ≤ 0.001) but no differences existed in HF readmission rate (14.8% vs. 13.2%, p = 0.610), cardiovascular mortality (4.4% vs. 3.9%, p = 0.713) or residual MR ≥ 2+ (51.1% vs 51.7%, p = 0.371).

CONCLUSIONS

Dynamic evaluation of MR during TEER procedure through VPT was performed in patients with worse baseline risk who also presented higher all-cause mortality at 1-year follow-up. However, 1-year residual MR, cardiovascular mortality and HF readmission rate remained comparable suggesting that VPT might help in the management of MITRA-FR-like patients.

Cardiac Complications in Pregnant Women With Isolated Mitral Stenosis and Their Association With Echocardiographic Changes During Pregnancy

In women with mitral stenosis (MS), mitral valve gradients and right ventricular systolic pressure (RVSP) can increase in response to the physiologic stress of pregnancy. The prognostic significance of these echocardiographic changes has not been well studied. Pregnancy outcomes and serial echocardiograms were collected in women with MS prospectively recruited as part of a larger study on pregnancy outcomes. Third trimester echocardiograms were compared with baseline echocardiograms. Changes in mitral valve area (MVA), transmitral mean gradient (MG), and RVSP during pregnancy and their relationship to adverse cardiac events (CE) were examined. Fifty-six pregnancies in 47 women with MS were included. The MVA did not change during pregnancy (1.6 ± 0.6 cm² at baseline vs 1.7 ± 0.6 cm² in the third trimester, p = 0.46). There was an increase in the MG (8 ± 3 vs 11 ± 6 mm Hg, p <0.001) and the RVSP (39 ± 14 vs 47 ± 20 mm Hg, p <0.001) during the third trimester. Adverse CE occurred in 45% (25/56) of pregnancies. CE were associated with baseline MG>10 mm Hg, baseline RVSP >40 mm Hg, third-trimester MG>10 mm Hg, and RVSP >40 mm Hg. Women with mitral valve MG ≤10 mm Hg who had a normal RVSP at baseline and in the third trimester were at lowest risk for CE (11%) with a negative predictive value of 89%. In conclusion, baseline echocardiographic assessment of MS severity as well as changing echocardiographic parameters during pregnancy can help identify women at risk for cardiac complications during pregnancy.

Multimodal cardiovascular model for hemodynamic analysis: Simulation study on mitral valve disorders

Valvular heart diseases are a prevalent cause of cardiovascular morbidity and mortality worldwide, affecting a wide spectrum of the population. In-silico modeling of the cardiovascular system has recently gained recognition as a useful tool in cardiovascular research and clinical applications. Here, we present an in-silico cardiac computational model to analyze the effect and severity of valvular disease on general hemodynamic parameters. We propose a multimodal and multiscale cardiovascular model to simulate and understand the progression of valvular disease associated with the mitral valve. The developed model integrates cardiac electrophysiology with hemodynamic modeling, thus giving a broader and holistic understanding of the effect of disease progression on various parameters like ejection fraction, cardiac output, blood pressure, etc., to assess the severity of mitral valve disorders, naming Mitral Stenosis and Mitral Regurgitation. The model mimics an adult cardiovascular system, comprising a four-chambered heart with systemic, pulmonic circulation. The simulation of the model output comprises regulated pressure, volume, and flow for each heart chamber, valve dynamics, and Photoplethysmogram signal for normal physiological as well as pathological conditions due to mitral valve disorders. The generated physiological parameters are in agreement with published data. Additionally, we have related the simulated left atrium and ventricle dimensions, with the enlargement and hypertrophy in the cardiac chambers of patients with mitral valve disorders, using their Electrocardiogram available in Physionet PTBI dataset. The model also helps to create 'what if' scenarios and relevant analysis to study the effect in different hemodynamic parameters for stress or exercise like conditions.

Pulmonary Artery Systolic Pressure Response to Exercise in Patients with Rheumatic Mitral Stenosis: Determinants and Prognostic Value

BACKGROUND

Pulmonary hypertension in response to exercise is a marker of the hemodynamic severity of mitral stenosis (MS). However, the factors related to elevated pulmonary pressure with exercise are not well defined. The aim of this study was to assess the parameters associated with the pulmonary pressure response to exercise in patients with pure rheumatic MS. An additional aim was to determine the impact of exercise-induced pulmonary hypertension on clinical outcome.

METHODS

One hundred thirty patients with MS (94% women; mean age, 45 ± 11 years) underwent exercise echocardiography. A range of echocardiographic parameters were obtained at rest and at peak exercise. Symptom-limited graded ramp bicycle exercise was performed in the supine position. The primary end point was mitral valve intervention, either percutaneous or surgical.

RESULTS

In the overall population, systolic pulmonary artery pressure (SPAP) increased from 38.3 ± 13.4 mm Hg at rest to 65.8 ± 20.7 mm Hg during exercise. Increases in mean mitral gradient, right ventricular function, left atrial volume, and net atrioventricular compliance were independently associated with SPAP at peak exercise, after adjusting for changes in heart rate. During the follow-up period (median, 17 months; range, 1-45 months), 46 adverse clinical events were observed. By multivariate Cox proportional-hazards analysis adjusted for age and sex, SPAP achieved at peak exercise was an important predictor of adverse outcome (adjusted hazard ratio, 1.025; 95% CI, 1.010-1.040; P = .001). New York Heart Association functional class (adjusted hazard ratio, 2.459; 95% CI, 1.509-4.006; P < .001) and the interaction between valve area and net atrioventricular compliance (P = .001) were also significant predictors of adverse events. Time-dependent areas under the receiver operating characteristic curve for the model with SPAP during exercise were better than for the model with SPAP at rest, with a significant improvement from 3 years onward.

CONCLUSIONS

In patients with MS, the pulmonary artery pressure response to exercise is determined by a combination of factors, including transmitral mean gradient at exercise, net atrioventricular compliance, left atrial volume, and right ventricular function. Pulmonary artery pressure at peak exercise is a predictor of clinical outcomes and adds incremental prognostic value beyond that provided by standard resting measurements, including valve area.

Can stress echocardiography identify patients who will benefit from percutaneous mitral valve repair?

The aim of the current study was to investigate whether stress echocardiography improves selection of patients who might have clinical benefit from percutaneous mitral valve repair with the MitraClip. In total, 39 patients selected for MitraClip implantation underwent preprocedural low-dose stress (dobutamine or handgrip) echocardiography from which stroke volume, ejection fraction and MR grade were measured. Outcome after MitraClip implantation was determined by New York Heart Association classification and Quality of Life questionnaires. Clinical benefit from MitraClip treatment was defined as survival and NYHA class I–II at 6 months follow-up. In total, 36 patients with a technically successful procedure were included in the analysis (mean age 79 ± 8 years, 47% male, 50% functional MR). Clinical benefit was achieved in 18 patients. All seven patients with MR decreasing during stress remained in NYHA III–IV or died within 6 months, while 62% (18 out of 29) of the patients with stable or increased MR during stress had clinical benefit (p = 0.008). Significant increase in Quality of Life on 4/8 subscales of the RAND Short Form-36 questionnaire was observed: Physical Functioning (p < 0.001), Social Functioning (p < 0.001), Mental Health (p = 0.022) and Vitality (p = 0.026) was seen in patients with an increase in stroke volume during stress echocardiography. Patients with a decreased MR during preprocedural stress echocardiography remained more symptomatic than patients with a stable or increased MR during stress. Stress echocardiography may support patient selection for percutaneous mitral valve repair.

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.

Assessment of LV ejection fraction using real-time 3D echocardiography in daily practice: direct comparison of the volumetric and speckle tracking methodologies to CMR

AIMS

This study is the first to directly compare two widely used real-time 3D echocardiography (RT3DE) methods of cardiac magnetic resonance imaging (CMR) and assess their reproducibility in experienced and less experienced observers.

METHODS

Consecutive patients planned for CMR underwent RT3DE within 8 h of CMR with Philips (volumetric method) and Toshiba Artida (speckle tracking method). Left ventricular ejection fraction (LVEF), left ventricular end-diastolic volume (LVEDV) and end-systolic volume (LVESV) were measured using RT3DE, by four trained observers, and compared with CMR values.

RESULTS

Thirty-five patients were included (49.7 ± 15.7 years; 55 % male), 30 (85.7 %) volumetric and 27 (77.1 %) speckle tracking datasets could be analysed. CMR derived LVEDV, LVESV and LVEF were 198 ± 58 ml, 106 ± 53 ml and 49 ± 15 %, respectively. LVEF derived from speckle tracking was accurate and reproducible in all observers (all intra-class correlation coefficients (ICC) > 0.86). LVEF derived from the volumetric method correlated well to CMR in experienced observers (ICC 0.85 and 0.86) but only moderately in less experienced observers (ICC 0.58 and 0.77) and was less reproducible in these observers (ICC = 0.55). Volumes were significantly underestimated compared with CMR (p < 0.001).

CONCLUSION

This study demonstrates that both RT3DE methodologies are sufficiently accurate and reproducible for use in daily practice. However, experience importantly influences the accuracy and reproducibility of the volumetric method, which should be considered when introducing this technique into clinical practice.