Evaluation of left ventricular filling pressures by the Tei index

Non-invasive cardiac allograft rejection surveillance: reliability and clinical value for prevention of heart failure

Allograft rejection-related acute and chronic heart failure (HF) is a major cause of death in heart transplant recipients. Given the deleterious impact of late recognized acute rejection (AR) or non-recognized asymptomatic antibody-mediated rejection on short- and long-term allograft function improvement of AR surveillance and optimization of action strategies for confirmed AR can prevent AR-related allograft failure and delay the development of cardiac allograft vasculopathy, which is the major cause for HF after the first posttransplant year. Routine non-invasive monitoring of cardiac function can improve both detection and functional severity grading of AR. It can also be helpful in guiding the anti-AR therapy and timing of routine surveillance endomyocardial biopsies (EMBs). The combined use of EMBs with non-invasive technologies and methods, which allow detection of subclinical alterations in myocardial function (e.g., tissue Doppler imaging and speckle-tracking echocardiography), reveal alloimmune activation (e.g., screening of complement-activating donor-specific antibodies and circulating donor-derived cell-free DNA) and help in predicting the imminent risk of immune-mediated injury (e.g., gene expression profiling, screening of non-HLA antibodies, and circulating donor-derived cell-free DNA), can ensure the best possible surveillance and management of AR. This article gives an overview of the current knowledge about the reliability and clinical value of non-invasive cardiac allograft AR surveillance. Particular attention is focused on the potential usefulness of non-invasive tools and techniques for detection and functional grading of early and late ARs in asymptomatic patients. Overall, the review aimed to provide a theoretical and practical basis for those engaged in this particularly demanding up-to-date topic.

Clinical value of myocardial performance index in patients with isolated diastolic dysfunction

AIMS

The Doppler-derived myocardial performance index (MPI) has been considered as a diagnostic and prognostic Doppler marker for many different clinical conditions. The purpose of this study was to determine the diagnostic accuracy of traditional Pulsed-wave Doppler (PWD-MPI) and Pulsed-wave tissue Doppler imaging (TDI-MPI) and the degree of agreement between these methods in patients with grade-I diastolic dysfunction (DDI) and a normal ejection fraction.

METHODS

Forty-seven consecutive ambulatory patients with DDI were compared to 51 healthy subjects with normal echocardiograms. All subjects underwent measurement of time intervals and MPI with PWD and pulsed TDI.

RESULTS

TDI-MPI and PWD-MPI were significantly higher in patients with DDI than in control subjects: 0.49 ± 0.14 vs. 0.40 ± 0.09 (P < 0.001) and 0.45 ± 0.11 vs. 0.37 ± 0.08 (P < 0.001), respectively. Cutoff values of TDI-MPI > 0.42 and PWD-MPI > 0.40 identified DDI subjects, with sensitivities of 74 and 64%; specificities of 61 and 69%; positive likelihood ratios of 1.9 and 2.0; and negative likelihood ratios of 0.42 and 0.53, respectively; no significant difference was noted between the areas under the ROC curves of TDI-MPI and PWD-MPI (P = 0.77). Bland-Altman plots showed wide limits of agreement between these indices: - 0.17 to 0.23 in healthy subjects and - 0.24 to 0.32 in DDI patients.

CONCLUSION

PWD-MPI and TDI-MPI showed poor clinical agreement and were not reliable parameters for the assessment of left ventricular diastolic function.

Comparison of systolic time interval measurement modalities for portable devices

Systolic time intervals (STI) have shown significant diagnostic and prognostic value to assess the global cardiac function. Their value has been largely established in hospital settings. Currently, STI are considered a promising tool for long-term patient follow-up with chronic cardiovascular diseases. Several technologies exist that enable beat-by-beat assessment of STI in personal health application scenarios. A comparative study is presented using the echocardiographic gold standard synchronized with impedance cardiography (ICG), phonocardiography (PCG) and photoplethysmography (PPG). The ability of these competing technologies in assessing the pre ejection period (PEP) and the left ventricle ejection time (LVET) is given a general overview with comparative results.

Risk Assessment in Patients with Depressed Left Ventricular Function After Myocardial Infarction Using the Myocardial Performance Index–Survival and Ventricular Enlargement (SAVE) Experience

BACKGROUND

Myocardial performance index (MPI) is a noninvasive, quantitative Doppler measure of global cardiac function, integrating systolic and diastolic functions. The prognostic significance of MPI is less clear for cardiovascular (CV) events after myocardial infarction (MI) among individuals at high risk with depressed left ventricular (LV) systolic function.

METHODS

We analyzed echocardiograms from 512 patients with depressed LV function after MI enrolled in the Survival and Ventricular Enlargement (SAVE) echocardiographic substudy. Baseline MPI measures were obtainable in 226 patients. The cohort was separated by median MPI (0.50). MPI was related to baseline clinical and echocardiographic characteristics, ventricular remodeling, and subsequent CV events, including recurrent MI, heart failure, CV death, and a composite of all CV end points.

RESULTS

An MPI of 0.5 or more was associated with larger infarct size and reduced LV systolic function at baseline; other baseline characteristics between the groups were similar. A total of 64 (28.3%) patients experienced CV events. Baseline MPI did not influence ventricular remodeling and did not modify the relationship between ventricular dilatation and CV events. After covariate adjustment, an MPI of 0.50 or higher remained an independent predictor for adverse CV events (hazard ratio [HR], 2.00, 95% confidence interval 1.17-3.43).

CONCLUSIONS

An MPI of 0.50 or greater is an independent predictor for CV events after MI in patients with known LV dysfunction.