Usefulness of the combined index of systolic and diastolic myocardial performance to identify cardiac allograft rejection

Echocardiographic Evaluation of the Post-Heart Transplant Patient

PURPOSE OF REVIEW

Significant practice variability exists with respect to the role and frequency of echocardiography after heart transplantation. We sought to illustrate key studies relating to the utility and diagnostic accuracy of echocardiography for the post-heart transplant patient.

RECENT FINDINGS

Several echocardiographic parameters correlate with acute heart transplant rejection, but there is enough heterogeneity between study results or in diagnostic accuracy, such that it precludes parameter use in isolation to rule out rejection. Newer techniques such as strain echocardiography may have better sensitivity. Similarly, resting and stress echocardiography can be combined with modern techniques such as myocardial contrast echocardiography to diagnose and prognosticate cardiac allograft vasculopathy, but studies have again demonstrated variable accuracy. Echocardiography remains an accessible tool in the evaluation and management of patients after heart transplantation. This modality can guide clinical judgment with real-time data and several fairly sensitive parameters for the detection of rejection, cardiac allograft vasculopathy, and other abnormalities. Often, auxiliary diagnostic modalities need to be combined to optimize diagnostic accuracy.

A Comprehensive Excursus of the Roles of Echocardiography in Heart Transplantation Follow-Up

Current guidelines for the care of heart transplantation recipients recommend routine endomyocardial biopsy and invasive coronary angiography as the cornerstones in the surveillance for acute rejection (AR) and coronary allograft vasculopathy (CAV). Non-invasive tools, including coronary computed tomography angiography and cardiac magnetic resonance, have been introduced into guidelines without roles of their own as gold standards. These techniques also carry the risk of contrast-related kidney injury. There is a need to explore non-invasive approaches providing valuable information while minimizing risks and allowing their application independently of patient comorbidities. Echocardiographic examination can be performed at bedside, serially repeated, and does not carry the burden of contrast-related kidney injury and procedure-related risk. It provides comprehensive assessment of cardiac morphology and function. Advanced echocardiography techniques, including Doppler tissue imaging and strain imaging, may be sensitive tools for the detection of minor myocardial dysfunction, thus providing insight into early detection of AR and CAV. Stress echocardiography may offer a valuable tool in the detection of CAV, while the assessment of coronary flow reserve can unravel coronary microvascular impairment and add prognostic value to conventional stress echocardiography. The review highlights the role of Doppler echocardiography in heart transplantation follow-up, weighting advantages and limitations of the different techniques.

Multiparametric Cardiac Magnetic Resonance Imaging Can Detect Acute Cardiac Allograft Rejection After Heart Transplantation

OBJECTIVES

The purpose of this study was to evaluate the sensitivity of multiparametric cardiac magnetic resonance imaging (CMR) for the detection of acute cardiac allograft rejection (ACAR).

BACKGROUND

ACAR is currently diagnosed by endomyocardial biopsy, but CMR may be a noninvasive alternative because of its capacity for regional myocardial structure and function characterization.

METHODS

Fifty-eight transplant recipients (mean age 47.0 ± 14.7 years) and 14 control subjects (mean age 47.7 ± 16.7 years) were prospectively recruited from August 2014 to May 2017 and underwent 97 CMR studies (83 transplant recipients, 14 control subjects) for assessment of global left ventricular function and myocardial T2, T1, and extracellular volume fraction (ECV). CMR studies were divided into 4 groups on the basis of biopsy grade: control subjects (n = 14), patients with no ACAR (no history of ACAR; n = 36), patients with past ACAR (history of ACAR; n = 24), and ACAR+ patients (active grade ≥1R ACAR; n = 23).

RESULTS

Myocardial T2 was significantly higher in patients with past ACAR compared with those with no ACAR (51.0 ± 3.8 ms vs. 49.2 ± 4.0 ms; p = 0.02) and in patients with no ACAR compared with control subjects (49.2 ± 4.0 ms vs. 45.2 ± 2.3 ms; p < 0.01). ACAR+ patients demonstrated increased T2 compared with the no ACAR group (52.4 ± 4.7 ms vs. 49.2 ± 4.0 ms, p < 0.01) but not compared with the past ACAR group. In contrast, ECV was significantly elevated in ACAR+ patients compared with transplant recipients without ACAR regardless of history of ACAR (no ACAR: 31.5 ± 3.9% vs. 26.8 ± 3.3% [p < 0.01]; past ACAR: 31.5 ± 3.9% vs. 26.8 ± 4.0% [p < 0.01]). Receiver operating characteristic curve analysis revealed that a combined model of age at CMR, global T2, and global ECV was predictive of ACAR (area under the curve = 0.84).

CONCLUSIONS

The combination of CMR-derived myocardial T2 and ECV has potential as a noninvasive tissue biomarker for ACAR. Larger studies during acute ACAR are needed for continued development of multiparametric CMR for transplant recipient surveillance.

Relationship Between Tei Index and PEP-Derived Myocardial Performance Index in Sinus Rhythm

The goal of this study was to evaluate the preejection time (PEP)-derived myocardial performance index (MPI) in hypertensive (HT) patients with sinus rhythm and its relationship to the classic Tei index. One hundred five patients were enrolled in the study (65 HT and 40 control subjects). The mean age of all patients was 50.5 ± 15 years and 60% were female. Echocardiography was performed on all patients. MPI was measured with the classic Tei method (MPI-Tei index) and the PEP-derived MPI method by using tissue Doppler echocardiography. Although the MPI-Tei index is defined as the ratio of isovolumetric contraction time (IVCT) along with isovolumetric relaxation time (IVRT) to ejection time (ET), PEP-derived MPI is defined as the ratio of PEP and IVRT to ET. We compared echocardiographic data between the HT group and the control group. MPI-Tei index and the PEP-derived MPI values were higher in the HT group compared with controls (0.52 ± 0.10 vs 0.39 ± 0.07, P < 0.001, and 0.51 ± 0.09 vs 0.39 ± 0.07). PEP-derived MPI was strongly correlated with the MPI-Tei index (r = 0.945, P < 0.001). Our study determined that the PEP-derived MPI might be used in the evaluation of left ventricular function in patients with HT, similar to the classic MPI-Tei index.

Diagnostic performance of echocardiography for the detection of acute cardiac allograft rejection: a systematic review and meta-analysis

Objective

Many studies have addressed the diagnostic performance of echocardiography to evaluate acute cardiac allograft rejection compared with endomyocardial biopsy. But the existence of heterogeneity limited its clinical application. Thus, we conducted a comprehensive, systematic literature review and meta-analysis for the purpose.

Methods

Studies prior to September 1, 2014 identified by Medline/PubMed, EMBASE and Cochrance were examined by two independent reviews. We conducted meta-analysis by using Meta-DiSc 1.4 software. An assessment tool of QUADAS-2 was applied to evaluate the risk of bias and applicability of the studies.

Results

Thirty studies met the inclusion criteria of meta-analysis. The four parameters of pressure half time, isovolumic relaxation time, index of myocardial performance and late diastolic mitral annular motion velocity were included in the meta-analysis, with a pooled diagnostic odds ratio of 10.43, 6.89, 15.95 and 5.68 respectively, and the area under the summary receiver operating characteristic curves value of 0.829, 0.599, 0.871 and 0.685 respectively.

Conclusion

The meta-analysis and systematic review demonstrate that no single parameter of echocardiography showed a reliable diagnostic performance for acute cardiac allograft rejection. A result of echocardiography for ACAR should be comprehensively considered by physicians in the context of clinical presentations and imaging feature.

Improvement of the myocardial performance index in atrial fibrilation patients treated with amiodarone after cardioversion

PURPOSE

This study evaluated the response to electrical cardioversion (EC) and the effect on the myocardial performance index (MPI) in patients with persistent and long-standing persistent atrial fibrillation (AF).

METHODS

We enrolled 103 patients (mean age 69.6 ± 8.9 years, 40.7% males) with a diagnosis of persistent and long-standing persistent AF. EC was applied to all patients after one g of amiodarone administration. Echocardiographic findings before EC were compared in patients with successful versus unsuccessful cardioversions and in patients with maintained sinus rhythm (SR) versus those with AF recurrence at the end of the first month. We also compared echocardiographic data before EC versus at the end of the first month in the same patients with maintained SR.

RESULTS

SR was achieved in 72.8% of patients and was continued at the end of the first month in 69.3% of the patients. The MPI value of all patients was found to be 0.73 ± 0.21. The size of the left atrium was determined to be an independent predictor of the maintenance of SR at 1 month. In subgroup analyses, when we compared echocardiographic findings before EC and at the end of the first month in patients with maintained SR, the MPI (0.66 ± 0.14 vs 0.56 ± 0.09, p < 0.001) values were significantly decreased.

CONCLUSIONS

Our study is the first to show impairment of the MPI, which is an indicator of systolic and diastolic function, in patients with persistent and long-standing persistent AF and improvement of the MPI after successful EC.

The Tei index and asymptomatic myocarditis in children with severe dengue

This study aimed to assess myocardial involvement in infants and children with severe dengue (as per the new World Health Organization [WHO] classification 2009) using the Tei index. This prospective observational study was conducted in the Department of Pediatrics, PGIMER and the associated Dr. RML Hospital, New Delhi from August to December 2010. The study included 67 children (ages 3 months-14 years) who satisfied the WHO criteria for the diagnosis of probable dengue fever with warning signs or severe dengue and tested positive for dengue via immunoglobulin-M (IgM) capture enzyme-linked immunoassay (MAC-ELISA). The patients were subjected to a complete blood count, liver function tests, renal profile, electrocardiography, myocardial band enzymes of creatine phosphokinase (CPK-MB), chest x-ray, abdomen ultrasonography, and two-dimensional echocardiography with color-flow Doppler mapping. Ejection fraction and Tei index measurements were performed. Significantly fewer patients with severe dengue were found to have myocardial involvement at admission by ejection fraction (48 %) and E/E' (37 %), than by the Tei index (70 %). Of the 67 patients with severe dengue, one died, giving a case fatality rate of 1.5 %. At discharge, the Tei index persisted on the high side for patients with myocardial involvement, whereas the ejection fraction improved for the majority of them. Most of the patients with severe dengue had asymptomatic myocarditis, as evident by a deranged Tei index, which improved but did not normalize by the time of discharge, necessitating a longer follow-up period. For the majority of the patients, inotropic support was not required to maintain hemodynamic stability.

Myocardial performance index (MPI) is not influenced by increased left ventricular mass in healthy obese men

BACKGROUND

Notwithstanding its clinical use as a reliable measure of left ventricular performance, little is known about whether myocardial performing index (MPI) is influenced by increased left ventricular mass (LVM) in healthy obese individuals.

AIM

The present study was targeted at investigating the impact of increased LVM on the LV MPI in healthy obese men.

SUBJECTS AND METHOD

Sixty-six normal male subjects were involved in this study. The subjects were divided according to their body mass index (BMI), into group I (BMI=20-24.9, n=37, mean age 33.405±10.277 years) which served as the control group, and group II (BMI=≥ 30, n=29, mean age 39.208±10.214 years). The MPI was determined in all subjects using the following formula proposed by Tei: MPI=IVCT+IVRT/ET. LVM was calculated according to the following Devereux formula as: LVM=0.8[1.04(IVSd+PWTd+LVIDd)-(LVIDd)] +0.6.

RESULTS

There were no significant differences in MPI between control subjects and obese subjects with increased LVM (p>0.05). Additionally, there was no linear correlation between MPI and LVM (R(2)=0.0003, p=0.89).

CONCLUSION

MPI is a simple and accurate tool for the quantitative assessment of left ventricular function. Because of its ease of application, cost effectiveness, and reproducibility, this tool could be regarded as a principal measurement for comprehensive hemodynamic studies. MPI values (according to the Tei index) did not vary significantly between healthy obese and morbidly obese individuals, and therefore may have limited utility for predicting cardiac diseases in at-risk obese individuals.

Myocardial performance index suggests optimal fluid loss during hemodialysis

BACKGROUND

Patients on long-term maintenance hemodialysis (HD) are at high risk of developing cardiovascular disease and suffering various cardiovascular complications during HD.

HYPOTHESIS

The purpose of this study was to evaluate the influence of changing loading conditions on the myocardial performance index (MPI) in patients on long-term HD and to specify an optimal level of fluid loss during HD that would maintain stable global cardiac function.

METHODS

The study consisted of 52 patients with end-stage renal failure (ESRF), mean age 56±11.7 y, range: 25-80 y, on regular HD. For each patient a complete echocardiographic-Doppler examination was performed before and after HD. Systolic and diastolic parameters of left ventricular function were measured, and the myocardial performance index (MPI) was calculated.

RESULTS

The MPI was significantly prolonged after HD (0.47±0.15 before HD versus 0.59±0.16 after HD, p < 0.001). Mean change in body weight during HD was 2.1±0.86 kg. The MPI did not change significantly in patients with intradialytic weight loss up to 1.75 kg.

CONCLUSIONS

The MPI value seems to be independent of acute preload changes only when fluid loss is less than 1.75 kg. A 1.75-kg fluid loss during HD seems to be the optimal goal. In ESRF patients on HD, the MPI seems to be a good indicator of global left ventricular function and potentially a valuable aid in the effort to maintain optimal fluid balance.

Diagnostic performance of multisequential cardiac magnetic resonance imaging in acute cardiac allograft rejection

AIMS

We evaluated cardiac magnetic resonance imaging (CMR) as a non-invasive test for cardiac allograft rejection.

METHODS AND RESULTS

We performed CMR on 50 heart-transplant recipients. Acute rejection was confirmed in 11 cases by endomyocardial biopsy (EMB) and presumed in 8 cases with a recent fall in left-ventricular ejection fraction (LVEF) not attributable to coronary allograft vasculopathy. Control patients had both normal LVEF and no significant rejection on EMB. Cardiac magnetic resonance imaging evaluated myocardial function, oedema, and early and late post-Gadolinium-DTPA contrast enhancement. Patients with confirmed rejection demonstrated elevated early relative myocardial contrast enhancement (4.1 +/- 0.3 vs. 2.8 +/- 0.2, P < 0.001) and a trend to higher oedema suggested by higher relative myocardial intensity on T(2)-weighted imaging compared to controls (2.1 +/- 0.1 vs. 1.7 +/- 0.1, P = 0.1). With rejection defined as increased early contrast enhancement or myocardial oedema, the sensitivity and specificity of CMR compared with EMB were 100 and 73%, respectively. Eight patients with presumed rejection also had elevated early myocardial contrast enhancement compared with controls, (8.7 +/- 1.9 vs. 2.8 +/- 0.2, P < 0.05), which reduced following increased immunosuppression (8.7 +/- 1.9 vs. 4.6 +/- 1.2, P < 0.05). In these patients LVEF improved following increased immunosuppression (32 +/- 5 vs. 46 +/- 5%, P < 0.05).

CONCLUSION

Cardiac magnetic resonance imaging is a promising modality for non-invasive detection of cardiac allograft rejection.

The role of multimodality cardiac imaging in the transplanted heart

Heart transplantation (HT) is an established life-saving treatment option for patients with end-stage heart failure. Despite many advances in the field, the development of acute cellular rejection (ACR) and cardiac allograft vasculopathy (CAV) represent significant causes of 1- and 5-year morbidity and mortality, respectively. The search for noninvasive techniques to assess cardiac allograft function and detect treatable ACR and CAV remains a priority objective for heart transplant professionals. In this review we will: 1) highlight the clinical significance of ACR and CAV in adult cardiac transplant recipients and 2) discuss how different noninvasive imaging modalities (echocardiography, cardiac computed tomography, myocardial perfusion imaging, and cardiac magnetic resonance) have been used in the evaluation of these clinical challenges after HT.

Measurement of the myocardial performance index in ambulatory patients with heart failure: correlation with other clinical and echocardiographic parameters and independent prognostic value

BACKGROUND

Many echocardiographic parameters have been proposed for the assessment of the patients with heart failure (HF). Recently, the myocardial performance index (MPI) has been shown to be an accurate index of myocardial function. We assessed the correlation with other clinical and echocardiographic measurements and the prognostic value of MPI in patients with HF.

METHODS AND RESULTS

The MPI was assessed in 112 consecutive patients with persistent symptoms of HF (II-III NYHA class), sinus rhythm, LV systolic dysfunction (defined by an ejection fraction <or= 45%). At multivariable analysis, only NYHA class and ejection fraction were independently related to MPI. The severity of mitral regurgitation and MPI were the only parameters independently related to the incidence of death or cardiovascular hospitalizations. A MPI > 0.55 (median value) and medium to severe mitral regurgitation were associated with a relative risk of cardiovascular events of 18.7 (95% confidence interval [CI], 16.6-20.7; P < 0.005) and of 3.03 (95% CI, 2-4.1; P = 0.035), respectively.

CONCLUSIONS

In our patients with HF, MPI was the best predictor of cardiovascular events. Mitral regurgitation was the only other variable which had an additive prognostic value at multivariate analysis.

Coenzyme Q10 improves diastolic function in children with idiopathic dilated cardiomyopathy

We aimed to determine the effect of supplementation with coenzyme Q10 on conventional therapy of children with cardiac failure due to idiopathic dilated cardiomyopathy. In a prospective, randomized, double-blinded, placebo-controlled trial, we randomized 38 patients younger than 18 years with idiopathic dilated cardiomyopathy to receive either coenzyme Q10, chosen for 17 patients, or placebo, administered in the remaining 21. Echocardiographic systolic and diastolic function parameters were determined for every patient at baseline, and after 6 months of supplementation. The index score for cardiac failure in children as established in New York was used for assessing the functional class of the patients. After 6 months supplementation, 10 patients randomized to receive coenzyme Q10 showed improvements in the grading of diastolic function, this being significantly more than that achieved by those randomized to the placebo group (p value = 0.011). The mean score for the index of cardiac failure index for those receiving coenzyme Q10 was also lower than the control group (p value = 0.024).Our results, therefore, indicate that administration of coenzyme Q10 is useful in ameliorating cardiac failure in patients with idiopathic dilated cardiomyopathy through its significant effect on improving diastolic function.

[Echocardiography-derived Tei index during surgery, a predictor of postoperative cardiovascular complications]

BACKGROUND AND OBJECTIVE

The Tei index is a Doppler echocardiographic parameter that reflects both systolic and diastolic myocardial function. Our aim was to monitor the Tei index by transesophageal echocardiography during noncardiac surgery to explore the correlation between this parameter and the incidence of postoperative cardiovascular complications.

MATERIAL AND METHODS

Patients at risk of cardiovascular complications were enrolled. The Tei index was derived from the pattern of pulsed Doppler transmitral filling and aortic outflow, by dividing the sum of isovolumetric contraction and relaxation intervals by ejection time in milliseconds.

RESULTS

Seventy-three patients (58% men) were enrolled. The mean (SD) age was 68 (12) years. Two groups were identified based on myocardial function. A Tei index over 0.35 defined group 2 (n = 25) and correlated with a larger number of postoperative cardiovascular events. In patients with a normal Tei index less than 0.35 (group 1, n = 48), the incidence of cardiovascular complications was lower. Hypotension occurred in 60% of patients in group 2 and 21% of those in group 1, hypertension in 24% of group 2 and 4.1% of group 1, and pulmonary edema in 8% of group 2 and 2.1% of group 1 (P < .05 for all comparisons).

CONCLUSIONS

This pilot study found that patients with a high Tei index were more likely to develop postoperative cardiovascular complications. This index may provide a useful indicator to take into consideration in planning hemodynamic management when patients have a history of cardiovascular disease.

Cardiovascular magnetic resonance in the diagnosis of acute heart transplant rejection: a review

BACKGROUND

Screening for organ rejection is a critical component of care for patients who have undergone heart transplantation. Endomyocardial biopsy is the gold standard screening tool, but non-invasive alternatives are needed. Cardiovascular magnetic resonance (CMR) is well suited to provide an alternative to biopsy because of its ability to quantify ventricular function, morphology, and characterize myocardial tissue. CMR is not widely used to screen for heart transplant rejection, despite many trials supporting its use for this indication. This review summarizes the different CMR sequences that can detect heart transplant rejection as well as the strengths and weaknesses of their application.

RESULTS

T2 quantification by spin echo techniques has been criticized for poor reproducibility, but multiple studies show its utility in screening for rejection. Human and animal data estimate that T2 quantification can diagnose rejection with sensitivities and specificities near 90%. There is also a suggestion that T2 quantification can predict rejection episodes in patients with normal endomyocardial biopsies.T1 quantification has also shown association with biopsy proven rejection in a small number of trials. T1 weighted gadolinium early enhancement appeared promising in animal data, but has had conflicting results in human trials. Late gadolinium enhancement in the diagnosis of rejection has not been evaluated.CMR derived measures of ventricular morphology and systolic function have insufficient sensitivity to diagnose mild to moderate rejection. CMR derived diastolic function can demonstrate abnormalities in allografts compared to native human hearts, but its ability to diagnose rejection has not yet been tested.There is promising animal data on the ability of iron oxide contrast agents to illustrate the changes in vascular permeability and macrophage accumulation seen in rejection. Despite good safety data, these contrast agents have not been tested in the human heart transplant population.

CONCLUSION

T2 quantification has demonstrated the best correlation to biopsy proven heart transplant rejection. Further studies evaluating diastolic function, late gadolinium enhancement, and iron oxide contrast agents to diagnose rejection are needed. Future studies should focus on combining multiple CMR measures into a transplant rejection scoring system which would improve sensitivity and possibly reduce, if not eliminate, the need for endomyocardial biopsy.

Usefulness and limitations of transthoracic echocardiography in heart transplantation recipients

Transthoracic echocardiography is a primary non-invasive modality for investigation of heart transplant recipients. It is a versatile tool which provides comprehensive information about cardiac structure and function. Echocardiographic examinations can be easily performed at the bedside and serially repeated without any patient's discomfort. This review highlights the usefulness of Doppler echocardiography in the assessment of left ventricular and right ventricular systolic and diastolic function, of left ventricular mass, valvular heart disease, pulmonary arterial hypertension and pericardial effusion in heart transplant recipients. The main experiences performed by either standard Doppler echocardiography and new high-tech ultrasound technologies are summarised, pointing out advantages and limitations of the described techniques in diagnosing acute allograft rejection and cardiac graft vasculopathy. Despite the sustained efforts of echocardiographic technique in predicting the biopsy state, endocardial myocardial biopsies are still regarded as the gold standard for detection of acute allograft rejection. Conversely, stress echocardiography is able to identify accurately cardiac graft vasculopathy and has a recognised prognostic in this clinical setting. A normal stress-echo justifies postponement of invasive studies. Another use of transthoracic echocardiography is the monitorisation and the visualisation of the catheter during the performance of endomyocardial biopsy. Bedside stress echocardiography is even useful to select appropriately heart donors with brain death. The ultrasound monitoring is simple and effective for monitoring a safe performance of biopsy procedures.

Echocardiography in the cardiac transplant recipient

Despite the widespread use of echocardiography in the cardiac allograft recipient, the clinical usefulness of this practice is not well defined. In this article, the authors review the spectrum of echocardiographic findings in the adult heart transplant patient. Appreciation of typical alterations from "normal" allows the transplant physician to identify clinically significant changes and to avoid unnecessary invasive procedures based on misinterpretation of these differences. Though abnormalities of systolic and diastolic function correlate with episodes of acute rejection, the primary diagnostic usefulness of echocardiography in acute rejection is guiding the endomyocardial biopsy. Additionally, echocardiography has found a role as a supplement to invasive angiography in the diagnosis of cardiac allograft vasculopathy.

Measuring patient-reported outcomes in solid organ transplant recipients: an overview of instruments developed to date

Improvements in organ preservation methods, immunosuppressive regimens and general post-transplant care have resulted in an increased life expectancy and a continually decreasing morbidity after solid organ transplantation. As attention gradually moves towards improving subjective patient outcomes, the use of patient-reported outcome measures (PROs) thus becomes increasingly important in post-transplant patient management. This paper provides a brief systematic overview of the transplant-specific PRO measures, and their psychometric properties, developed and used in solid organ transplant recipients to date. PRO measures may focus on or encompass different aspects of life relevant to organ transplant patients: overall quality of life (QOL), physical, psychological and social functioning, and adherence. Overall QOL can be measured using transplant-specific or generic QOL instruments, or a combination of both. In general, very little information is available on the psychometric properties of PRO measures, and there is no gold standard for PRO measurement. Transplant-specific and generic PRO instruments are complementary. Generic instruments will continue to be important for economic evaluations, but transplant-specific instruments may be more useful for patient management purposes, as they are generally more sensitive to small but clinically relevant changes in outcomes in transplant populations.

Abnormal total ejection isovolume index as early noninvasive marker of chronic rejection in heart transplantation*

Abnormally high myocardial performance index (MPI) is a Doppler-derived marker of combined systolic and diastolic left ventricular (LV) dysfunction. To identify early stage allograft dysfunction by MPI, we studied 154 long-term heart transplantation (HT) recipients (131 male, aged 51 +/- 13 years at HT, mean follow up 8.4 +/- 3.5 years), with normal left ventricular ejection fraction (LVEF) and free from acute rejection (AR), and 25 normals (13 male, aged 39 +/- 16 years). Rejection score (RS) on endomyocardial biopsy was calculated in the first year. MPI was prolonged (0.45 +/- 0.18 vs. 0.28 +/- 0.10, P = 0.0001) in patients and directly related with mean time from HT (P = 0.001), higher cumulative dosages of cyclosporine at 3 months (P = 0.01), 6 months (P = 0.03), 1 year (P = 0.02), 3 years (P = 0.04) and with cumulative dosage of methylprednisolone at 1 year (P = 0.002). The index was inversely related with mean age at HT (P = 0.002) and tended to be directly related with RS at 1 year (P = 0.05). Thus, MPI is abnormal in long-term HT recipients with normal LVEF. Its direct relation with time from HT as well as immunosuppressive load suggests an early stage of graft dysfunction because of chronic rejection. Extended prospective studies are warranted to clarify its potential role as a negative prognostic marker in HT.

Effects of Alcohol Septal Ablation for Hypertrophic Obstructive Cardiomyopathy on Doppler Tei Index: A Midterm Follow-Up

Alcohol septal ablation (PTSMA) improves outflow gradient, left ventricular (LV) diastolic function, and symptoms in patients with hypertrophic obstructive cardiomyopathy (HOCM). Tei index (TI) is a Doppler parameter reflecting both systolic and diastolic LV function. Midterm changes of TI after PTSMA have not been determined up to now. Twenty-seven consecutive patients (mean age 53 +/- 13 years) with symptomatic HOCM underwent PTSMA procedure. Clinical and echocardiographic data were collected at baseline, 6 and 12 months after PTSMA. TI decreased from 0.67 +/- 0.11 to 0.55 +/- 0.06, isovolumic contractile time (ICT) decreased from 74 +/- 20 to 48 +/- 11 ms, isovolumic relaxation time decreased from 146 +/- 25 to 117 +/- 9 ms, and LV ejection time decreased from 330 +/- 42 to 298 +/- 13 ms. LV remodeling was determined by LV dimension increase from 46 +/- 6 to 48 +/- 6 mm and basal septum thickness reduction from 22 +/- 4 to 15 +/- 3 mm. LV ejection fraction decreased from 78 +/- 7 to 73 +/- 6% and maximal outflow gradient decreased from 69 +/- 44 to 15 +/- 11 mmHg. All changes were statistically significant (P <0.01). Symptomatic improvement was characterized by relief of dyspnea (2.5 +/- 0.7 versus 1.4 +/- 0.6 NYHA class; P <0.01) and angina pectoris (2.6 +/- 0.9 versus 0.7 +/- 0.7 CCS class; P <0.01). PTSMA is an effective method of therapy for HOCM. Shortening of TI suggests the improvement of LV myocardial performance in the midterm follow-up.

Early detection by the Tei index of carvedilol-induced improved left ventricular function in patients with heart failure

Twenty-two patients (19 men) with heart failure (16 ischemic, 6 dilated cardiomyopathy; mean age of 67 +/- 6 years) in New York Heart Association classes I (2 patients), II (18 patients), and III (2 patients) under optimal therapy were strictly monitored after carvedilol supplementation. The Tei index decreased significantly from 0.87 +/- 0.17 to 0.53 +/- 0.29 (p <0.03). Conversely, the ejection fraction and transmitral Doppler flow analysis did not show significant improvement, despite a trend toward the amelioration of the ejection fraction, the E-/A-wave ratio, and atrial contribution. The Tei index could represent an earlier marker to evaluate drug-induced left ventricular function improvement in patients with heart failure and could represent a more sensitive tool to monitor left ventricular function during drug interventions.

Age dependency of the Tei index of myocardial performance

Despite its clinical use as a sensitive measure of left ventricular performance, little is known about whether the Tei index is influenced by aging. We determined the Tei index in 141 subjects without cardiovascular disease (age 16-78 years). There were statistically significant variations in ejection time, isovolumic relaxation time, and the Tei index with aging. There was a moderate linear correlation between isovolumic relaxation time and age (r = 0.49, P <.001) and the Tei index and age (r = 0.33, P <.001). This investigation demonstrated that when assessing myocardial performance in patients using this index, age-normalized values should be used.

Evaluation of myocardial performance index to predict mild rejection in cardiac transplantation

BACKGROUND

Early diagnosis of heart transplant rejection is mandatory, since even mild rejection can rapidly progress to more severe rejection. Noninvasive diagnosis of heart transplant rejection still remains a challenge.

HYPOTHESIS

The purpose of the study was to determine a possible association between myocardial performance index (MPI) and biopsy score of the heart transplant.

METHODS

This is a retrospective cohort analysis of 99 complete Doppler echocardiographic studies from 24 consecutive patients (23 men) performed within 24 h of endomyocardial biopsy. Mean age of the cohort was 50 +/- 9 years and mean time from transplantation was 19 +/- 21 months (1-81). All patients were in sinus rhythm. Myocardial performance index was calculated as the ratio of isovolumic contraction time plus isovolumic relaxation time divided by ejection time. Left ventricular dimensions, left ventricular mass, ejection fraction, and a number of Doppler indices (E-point velocity, A-point velocity, deceleration time, and deceleration slope) were also measured. The International Society for Heart and Lung Transplantation (ISHLT) grading system was used for the classification of endomyocardial biopsies.

RESULTS

Myocardial performance index was significantly prolonged (0.60 +/- 0.13, 0.68 +/- 0.08, 0.75 +/- 0.20, in biopsy scores 0, IA, and IB, respectively; p<0.001). Isovolumic contraction time was significantly prolonged; isovolumic relaxation time was not significantly changed. Ejection time and deceleration time were significantly shortened. Multivariate stepwise regression analysis revealed that MPI and deceleration time were the only independent predictors of biopsy score (r=0.48, F=10.53, p<0.0001).

CONCLUSION

Myocardial performance index seems to be a useful adjunct in the follow-up of cardiac transplant patients. These preliminary data suggest that a larger study may be indicated to clarify the relevance of myocardial performance index.

Can the index of myocardial performance be used to detect acute cellular rejection after heart transplantation?

The index of myocardial performance (IMP), combining systolic and diastolic function, was measured in 50 orthotopic heart transplant recipients to determine if it could be used to detect acute rejection. It was calculated as the sum of the isovolumic contraction time (IVCT) and isovolumic relaxation time (IVRT) divided by the ejection time. Comparison of intrarecipient changes in Doppler intervals between rejection and nonrejection states demonstrated an increase in IVCT and decrease in IVRT during rejection with no significant change in the IMP. Rejection is likely to be best detected by assessing these parameters independently rather than by measuring the IMP.