Time To Peak Filling Rate Research Articles

The Clinical Role of Cardiovascular Magnetic Resonance Imaging in the Assessment of Cardiac Diastolic Dysfunction

Echocardiography is the gold standard clinical tool for the evaluation of left ventricular diastolic dysfunction (LVDD) and is used to validate other cardiac imaging modalities in measuring diastolic dysfunction. We examined Cardiac Magnetic Resonance Imaging (CMR) in detecting diastolic dysfunction using the time-volume curve-derived parameters compared to echocardiographic diastolic parameters. We evaluated patients who underwent both CMR and transthoracic echocardiography (TTE) within 2 ± 1 weeks of each other. On echo, Doppler/Tissue Doppler Imaging (TDI) measurements were obtained. On CMR, peak filling rate (PFR), time to PFR (TPFR), 1/3 filling fraction (1/3FF), and 1/3 filling rate (1/3FR) were calculated from the time-volume curve. Using the commonly employed E/A ratio, 44.4% of patients were found to have LVDD. Using septal E/E' and lateral E/E', 29.6% and 48.1% of patients had LVDD, respectively. Correlation was found between left atrial (LA) size and E/A ratio (R = -0.36). Using LVDD criteria for CMR, 63% of patients had diastolic dysfunction. CMR predicted LVDD in 66.7% of the cases. CMR-derived diastolic filling parameters provided a relatively easy and promising method for the assessment of LVDD and can predict the presence of LVDD as assessed by traditional Doppler and TDI methods.

Normal and Range Value Evaluations Using Heart Risk View-Function Based on the Japanese Societyof Nuclear Medicine Working Group Database.

Background: Gated myocardial perfusion single-photon emission computed tomography (SPECT) has been used to non-invasively evaluate the left ventricular (LV) volume and function. This study aimed to measure the normal and range values for heart risk view-function (HRV-F) software using the Japanese Society of Nuclear Medicine Working Group (JSNM-WG) normal database and clarify the characteristics of the normal database. Methods:We used 206 myocardial perfusion short-axis images from the normal database. Ejection fraction (EF), end-systolic volume (ESV), end-diastolic volume (EDV), peak filling rate (PFR), 1/3 mean filling rate (MFR), time to PFR (TTPF), and TTPF divided by RR interval (TPFR/RR) were calculated. Phase parameters of 95% histogram bandwidth and standard deviation were also computed using the phase analysis. The relationships among phase parameters, LV volumes, and body surface area (BSA) were evaluated in the age group of ≤65 years. Results: Higher EF was observed in females than in males (p<0.0001). EDV and ESV were significantly higher in males than in females (p<0.0001). Additionally, PFR and 1/3 MFR significantly differed between sexes (p≤0.075). Phase parameters were higher in males than in females, and higher at stress than at rest. All diastolic parameters showed no significant differences between sexes in any age group, whereas differences have remained in phase values. Phase parameters were weakly correlated with EDV (r=0.31), ESV (r=0.43), and BSA (r=0.27), respectively. Conclusions: Mean normal and range values of the normal database were determined using the HRV-F software. The normal and range values can help diagnose gated SPECT data in patients with cardiac diseases.

Assessment of LV diastolic dysfunction in myocardial perfusion imaging: a correlative study with transthoracic echocardiography.

Myocardial perfusion imaging (MPI) by gated single-photon emission computed tomography (SPECT) is a feasible method in the evaluation of left ventricular perfusion and function. The purpose of this study was to determine the threshold and grading of left ventricular (LV) diastolic dysfunction (LVDD) using gated SPECT MPI. A total of 149 patients were recruited in the study. All of the patients underwent a standard 2-day stress/rest gated MPI study and transthoracic echocardiography within 2 weeks. The reconstructed rest-only images were analyzed by Cedar-Sinai's quantitative gated SPECT and the LV diastolic parameters, including peak filling rate (PFR), time to PFR (TTPF) and secondary PFR (PFR2) to PFR ratio were provided and compared to echocardiographic data. 68 (45.6%) and 81 (54.4%) of patients were categorized in LVDD-absent and LVDD-present groups on the basis of LVDD evidence in echocardiography, respectively. receiver-operating-characteristic analysis for PFR and TTPF was performed, resulting in diagnostic sensitivities of 70 and 57% and specificities of 60 and 75% for PFR <2.6 end-diastolic volumes (EDV)/s and TTPF>160.5 ms, respectively. Applying our previously used thresholds of <1.70 EDV/s for PFR, >208 ms for TTPF and >1 for PFR2/PFR, sensitivities and specificities of 9.9 and 96.6%, 9.9 and 95.6% and 13.8 and 88% were resulted, respectively. Grading of LVDD on the basis of MPI-obtained diastolic parameters showed considerable overlapping data by interquartile range. Gated SPECT MPI can be used as a highly specific means for detection of LV diastolic dysfunction when compared to echocardiography. However, grading of severity of diastolic heart failure appears to be impracticable.

Diastolic left ventricular functional indices: Comparison between gated myocardial perfusion SPECT and echocardiography

Introduction: Many patients have only diastolic dysfunction without any abnormality in systolic function. We compared cardiac diastolic parameters obtained by gated myocardial perfusion SPECT (Gated SPECT) with those evaluated by echocardiography. Methods: Forty-nine patients (aged 37-85 years, 19 males and 30 women) underwent Gated SPECT and echocardiography. Gated SPECT images were obtained with 16 frame/cardiac cycles. We derived the following diastolic indices: peak filling rate (PFR), time to PFR (TTPFR), mean filling rate in the first 1/3 of the diastole (MFR/3) and second filling rate (PFR2) due to left atrial contraction. In echocardiography we obtained the indices of ventricular filling: E wave, A wave, the E/A ratio, and the E wave deceleration time (DT) were considered. The LV isovolumic relaxation time (IVRT) was also determined. Results: There was no significant correlation between echocardiographic findings and diastolic gated SPECT findings. Using Post-Hoc One-way analysis significant difference was seen only in MFR/3 between diastolic dysfunction groups (P value=0.02). There was no significant difference in other diastolic gated SPECT variables in these groups. Conclusion: Diastolic parameters obtained from 16-frame/cardiac cycle gated SPECT didn’t correlate with echocardiographic indices.

Right Ventricular Dysfunction in Patients with Acute STEMI, Radionuclide-Based Assessment

Background: An acute myocardial infarction, particularly one that is large and transmural, can produce alterations in the topography of both the infarcted and noninfarcted regions of the ventricle. Cardiac remodeling after acute myocardial infarction (AMI) is characterized by molecular and cellular mechanisms involving both left and right ventricles. Objective: To study the right ventricular affection in patients with acute myocardial infarction of the left ventricle and treated with primary PCI. Methods: The study was done in the critical care department, Cairo University (in which 2,500 primary percutaneous coronary interventions (PCIs) are done annually). Forty patients with acute ST-elevation myocardial infarction (STEMI) were subjected to primary (PCI), we excluded all patients with RV infarction and patients with pulmonary hypertension. RV function was assessed by first pass radionuclide angiocardiography within 48 hours of admission. Results: Regarding the incidence of right ventricular dysfunction in patients with acute left ventricular STEMI who treated with 1ry PCI, there were 21 patients (52.5%) with RV EF% patients (47.5%) with RV time to peak filling rate (TPFR) > 180 msec. There was a significant relationship between right ventricular dysfunction and duration of ICU stay, impairment of LV systolic function, failure of complete resolution of ST segment elevation, failure of early peaking of cardiac enzymes, occurrence of in-hospital complications and one year mortality. Conclusion: The incidence of right ventricular dysfunction in patients with acute left ventricular STEMI is higher than expected and has a negative impact on their outcome.

Does Oral Metoprolol have Any Effect on the Functional Parameters and Perfusion Defects of the Left Ventricle?

Background: The role of Technetium-99 m (Tc-99m) labeled tracers has been discussed for the detection of viable myocardium. One of the methods that is considered to be used in the diagnosis of viability is gated Myocardial Perfusion Imaging (gMPI) conducted under the influence of Beta Blocker Drugs (BBD). Objective: The aim of this study is twofold: First, to evaluate the role of the Beta Blocker Drugs (BBD) on fixed perfusion defects on gated Myocardial Perfusion Imaging (gMPI) (myocardial viability) and second, to assess the role of BBD on the functional parameters of the left ventricle. Methods: 31 patients (28 men, 3 women) who were on BBD treatment and had fixed perfusion defects on their gMPI and submitted to fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) were prospectively enrolled to the study. One week after the completion of the stress-rest gMPI, rest gMPI was repeated for each patient while they were on BBD treatment. All systolic and diastolic functional measurements, perfusion defect extent and size were obtained during both rest gMPI studies with and without BBD. The parameters derived from FDG PET/CT were compared to those that were derived from gMPI without BBD. Results: A statistically significant difference between the scores of both groups was not observed, except the Time to Peak Filling Rate (TTPFR). End-systolic/diastolic volumes derived from gated FDG PET/CT were significantly lower than the ones derived from the gMPI presumably due to higher spatial resolution of the FDG PET/CT while the study did not reveal a statistically significant difference between the ejection fraction values. Conclusion: According to our results, metoprolol does not seem to change functional parameters of the left ventricle that were detected by gMPI except TTPFR. Besides, it seems that metoprolol does not affect the size of the perfusion defect, and therefore, it does not have a role to demonstrate the presence of viability that was confirmed via FDG PET/CT. Keywords: Beta blocker, 18F FDG PET/CT, gated myocardial perfusion imaging, fixed perfusion defect, metoprolol, viability.

Effects of alcohol septal ablation on left ventricular diastolic filling patterns in obstructive hypertrophic cardiomyopathy.

Alcohol septal ablation (ASA) has been shown to improve left ventricular (LV) diastolic function in patients with obstructive hypertrophic cardiomyopathy (HCM). However, its beneficial effect on diastolic function assessed by cardiac magnetic resonance (CMR) has not been reported. We investigated the mid-term changes of diastolic function by CMR combined with echocardiography in HCM patients after ASA at a median of 14-month follow-up. CMR parameters of diastolic function including peak filling rate (PFR), and time to peak filling rate (TPFR) were evaluated in 43 patients (aged 48±9years). LV diastolic function improved significantly measured by echocardiography with the decrease in ratio of transmitral early LV filling velocity (E) to early diastolic mitral lateral annular velocity (E') (14.20±1.17 to 11.58±1.16, p<0.001) and E-wave deceleration time (194.04±19.30 to 168.45±12.58 ms, p<0.001). PFR increased significantly with associated decrease in TPFR after ASA (both p<0.001) at follow-up. Furthermore, patients with larger decrease in LVOT gradients had a greater improvement of LV diastolic function, as measured by the reduction of E/E' (p<0.001) and increase of PFR (p<0.001). In conclusion, this study demonstrated that successful ASA results in both echocardiographic and CMR indices of diastolic function improvement after ASA at 14-month follow-up. ASA therapy can significantly reduce LVOT gradient and mitral regurgitation, both of which may contribute to the improvement of diastolic function.

Analysis of RV components after reoperation of the right ventricular outflow tract in patients with Tetralogy of Fallot

Methods 31 patients (20.6 ± 10.3 years) underwent an MRI examination before and after (20 ± 18 months) pulmonary valve replacement or reconstruction (PVR) for the volume overload of the RV. For segmental analysis of the RV, a custom made analysis software was developed. The method provides an automatic contour detection algorithm for the determination of the RV blood volume and enables the user to segregate the blood volume of the RVOT and the corpus based on anatomic landmarks and to generate volume-time-curves over a cardiac cycle. The analysis of volume-time-curves of the RV allowed calculation of Peak-Filling-Rate (PFR) and Time-to-Peak-Filling-Rate (TPFR), which are surrogate parameters for diastolic dysfunction.

CMR-DETERMINED LV DIASTOLIC DYSFUNCTION IN DIABETIC PATIENTS IS ASSOCIATED WITH INCREASED MYOCARDIAL EXTRACELLULAR VOLUME FRACTION

Diabetic myocardial changes include increased myocardial apoptosis, necrosis, collagen deposition and interstitial fibrosis. These may result in myocardial stiffness and alteration of myocardial extracellular volume fraction (ECV). In this pilot study, we hypothesize that CMR-determined LV diastolic dysfunction in diabetic patients is associated with increased ECV measured by T1 mapping. 17 DM patients (6 males, age 63±10 years old) without macrovascular diseases were examined on a 1.5T MR system. LV systolic and diastolic function was determined using a short-axis SSFP stack, T1 map and average LV myocardium T1 at pre- and post-contrast was derived from a T1 prep or a modified Look-Locker sequence performed in a mid-LV level. Post-contrast late gadolinium enhancement (LGE) CMR was performed 15 minutes post injection of Gd-DTPA. LV systolic function and LGE determination used commercial software CMR42. LV diastolic functional parameters including peak filling rate (PFR) and time to peak filling rate (TPFR) were calculated using MASS software and were blinded to T1 analysis. T1 calculation used CMR42 or a customized Matlab code. Myocardial ECV = (1-haematocrit) × (ΔR1myocardium/ΔR1blood). Increased ECV was defined as ECV > 30%. The average LV functional parameters in 17 subjects were in the normal range (LVEF=61±6%, LVESV=45±17 ml, LVEDV=113±33 ml, LVSV=68±19 ml, LVM=103±25 g). No focal LGE was observed in this patient cohort. 8 of 17 subjects had ECV> 30% (ECV=38±9%) and the other 7 subjects had ECV<30% (23±5%). There is no statistically significant difference (P>0.05) in LV systolic functional parameters of LVEF, LVESV, LVEDV, LVSV and LVM between the increased ECV and normal ECV group. However, a statistically significant difference (P<0.05) was observed among diastolic functional parameters of TPFR and PFR, with significantly longer TPFR (344±148 vs.156±32 ms) and lower PFR (220±50 vs. 295±74 ml/s) observed in the increased ECV group. Also a statistically significant difference (P<0.05) was observed in pre-contrast T1 measurements. Increased ECV was observed in diabetic patients with preserved systolic function and this was associated with altered LV diastolic function. The increased ECV may indicate the presence of diffuse interstitial fibrosis and myocardial stiffness, thus limiting the LV diastolic relaxation.

Clinical usefulness of a novel program "Heart Function View" for evaluating cardiac function from gated myocardial perfusion SPECT.

To investigate clinical usefulness of a novel program "Heart Function View (HFV)" for evaluating left ventricular (LV) function from myocardial perfusion SPECT (MPS), we compared LV functional parameters (F(x)) calculated by HFV with those obtained by the other similar programs QGS and cardioGRAF or by ultrasound echocardiography (UCG) and examined their correlations with clinical markers of heart failure: plasma BNP concentrations (BNPs) and exercise capacity. Studied patients (n = 60) underwent technetium-99m tetrofosmin quantitative gated MPS including treadmill exercise for examining heart disease. Myocardial stress images were acquired 30 min after the first tracer injection during maximal exercise. Three hours later, the second tracer was injected, and resting images were acquired. LV systolic F(x) [ejection fraction (EF), peak ejection rate (PER)] and diastolic F(x) [first third filling fraction (1/3FF), first third filling rate (1/3FR), peak filling rate (PFR), time to PFR (TPF)] were analyzed, and phase standard deviation (SD) and histogram bandwidth were obtained by phase analysis. LV end-diastolic volume (EDV), end-systolic volume (ESV) and EF obtained from HFV were well correlated with those from QGS, cardioGRAF and UCG. A diastolic parameter Doppler E/e' from UCG was significantly with PFR from HFV. There were good correlations between LVEDV, LVESV, LVEF, PER, PFR, 1/3FR, TPF and 1/3FF from HFV and those from cardioGRAF. LVEF, PER, 1/3FR, and PFR were significantly correlated with plasma BNP concentrations. In patients with non-ischemic heart disease (n = 42), phase SD and histogram bandwidth were correlated negatively with exercise capacity or PFR. HFV-derived LVF(x) are correlated with LVF(x) from the other programs or UCG, or with the clinical markers of heart failure and are thus useful in the functional assessment for patients with heart disease.

Evaluation of left ventricular diastolic function with a dedicated cadmium-zinc-telluride cardiac camera: comparison with Doppler echocardiography

To evaluate the relationships between measures of left ventricular (LV) filling dynamics at cadmium-zinc-telluride (CZT) imaging and indexes of LV diastolic function at transthoracic echocardiography. Two hundred and forty-seven patients underwent myocardial perfusion imaging at rest and after stress with a low-dose CZT protocol and a baseline transthoracic echocardiography study. All patients were submitted to invasive or computed coronary angiography. The peak filling rate (PFR) and the time to PFR (TPFR) were derived from gated CZT images as measures of LV filling dynamics. LV diastolic function was also evaluated at echocardiography and the presence of significantly increased LV filling pressures determined. Increased LV filling pressures at transthoracic echocardiography were evident in 103 (42%) patients. Interestingly, independently from the presence of coronary artery disease, there was a strict correlation between the presence and severity of LV diastolic dysfunction at echocardiography and CZT-derived measures of filling dynamics, i.e., PFR (P = 0.001) and TPFR (P = 0.001). At receiving operating characteristic analysis, a composite index of reduced PFR (≤2.11 end-diastolic volume s(-1)) and increased TPFR (>234 ms) showed a sensitivity of 84% and a specificity of 67% in unmasking the presence of elevated LV filling pressures at echocardiography. CZT-derived measures of LV filling dynamics correlate with echocardiographic parameters of diastolic function and may identify the presence of increased LV filling pressures.

Association of Iodine-123 BMIPP and MIBG Cardiac Uptakes with Left Ventricular Functional Parameters Assessed by Gated Myocardial Perfusion SPECT

We investigated how the degree of cardiac uptakes of radioactive fatty acid (FA) analog ( 123 I-BMIPP) or norepinephrine (NE) analog ( 123 I-MIBG) was related to left ventricular (LV) functional parameters in patients with heart disease, which might be a predictor of cardiac events. Patients with ejection fraction (EF) of 16.2%-82.2% underwent 123 I-BMIPP or 123 I-MIBG myocardial scintigraphy, and were followed up over 1177±486 days. LV systolic functional parameter EF, diastolic parameters 1/3FR (first third filling rate), PFR (peak filling rate), and TPF (time to PFR) were calculated using quantitative gated SPECT. 123 I-BMIPP uptake (n=30) was significantly correlated with EF, 1/3FR, and PFR but not TPF. 123 I-MIBG uptake (n=37) was also correlated with EF, 1/3FR, and PFR but not TPF. In contrast, TPF was positively correlated with age, and was significantly longer in women than in men. Such findings were also observed in normal EF patients (≥50%, n=100). Kaplan–Meier analysis showed the occurrence of earlier cardiac events in the case of patients with decreased 123 I-BMIPP and 123 I-MIBG uptake, decreased PFR, and prolonged TPF. The degree of decreased cardiac uptakes of FA and NE may be associated with the grade of systolic and diastolic dysfunctions assessed by EF, PFR, and 1/3FR. In contrast, prolonged TPF, another diastolic parameter, may rather be caused by aging and female gender, independent of EF. Despite these differences, myocardial FA metabolism impairment, cardiac sympathetic nerve inactivity, decreased PFR, and prolonged TPF may all indicate poor cardiac prognosis in patients with heart disease. Keywords123 I-BMIPP; 123 I-MIBG; Cardiac Function; Heart Failure

1081Constrictive Pericarditis in the Modern Cardiology Era Quantitative Analysis of Constrictive Physiology using Four-Dimensional MRI

Objectives: Accurate diagnosis of constrictive pericarditis (CP) is a well-recognized clinical challenge. Since magnetic resonance imaging (MRI) provides high resolution assessment of ventricular volumes, we sought to investigate left ventricular (LV) and right ventricular (RV) time-volume curve using four-dimensional MRI (4D MRI) in patients with CP. Methods: Fourteen patients with CP who had undergone surgery for pericardiectomy and 10 normal subjects were included. Three dimensional MRI covering the whole myocardium in the short axis projection was performed. LV and RV volumes were evaluated over the whole cardiac cycle to generate a four-dimensional MRI dataset for assessment of ventricular time volume curve yielding systolic function and filling parameters: end-diastolic and end-systolic volume, ejection fraction, filling time, early and late filling volume, E/A ratio, peak filling rate (PFR), and time to peak filling rate (TPFR). Results: In patients compared with normal subjects, LV and RV end-diastolic and end-systolic volumes were decreased (all P < 0.05), but biventricular ejection fraction was similar. The filling time of both ventricles was significantly shorter (both P < 0.001). In early diastole, LV and RV filling volumes were increased (P = 0.004, P < 0.001; respectively), in late diastole; however, LV and RV filling volumes were reduced (both P < 0.001). Biventricular E/A ratio and PFR were higher (all P < 0.001) and TPFR of the right ventricle was lower (P = 0.02) in patients compared with normal subjects. Conclusion: In patients with CP quantitative 4D MRI analysis provides reduction in end-diastolic and end-systolic volumes and demonstrated a typical hemodynamic response. In early diastole both ventricles have an increased filling, in late diastole, however; the constricted physiology allowed only a slight ventricular filling.

The effect of facilitated percutaneous coronary intervention on systolic synchrony performance in patients with acute myocardial infarction

Objective To evaluate the influence of thrombolysis,primary PCI and facilitated PCI via a transradial approach therapy on systolic performance and synchrony in patients with AMI using ERNA.Methods A total of 213 patients with their first anterior AMI were enrolled in this study.Seventy patients were randomized to a thrombolytic treatment group,71 patients to a primary PCI group and 72 patients to a facilitated PCI group.At 1 week and 28 weeks after AMI onset,parameters of the LVEF,peak ejection rate (PER),time to peak ejection rate (TPER),peak filling rate (PFR),time to peak filling rate (TPFR)and left ventricular systolic synchrony (LVSS) (PS,FWHM,PSD) were measured by ERNA with ventricular phase analysis.Major adverse cardiac events (MACE) such as post AMI angina,recurrence of MI or mortality were recorded.The t-test was used to compare the data.Results (1) There were no significant differences among the three groups in clinical characteristics.(2) The first CAG showed that the grade of the infarct related artery (IRA) in the primary PCI group (8.45％,6/71) was significantly lower than that in the thrombolytic treatment group (31.43％,22/70) (x2=11.69,P＜0.01) and also lower than that in the facilitated PCI group (30.56％,22/72) (x2 =11.09,P＜0.01).The TIMI-3 grade rate of IRA post PCI in the facilitated PCI group (98.61％,71/72) was higher than that in the primary PCI group (88.73％,63/71),x2=4.35,P＜0.05.(3) At 28 weeks after AMI,LVEF increased significantly from (42.75±3.47)％ to (50.45±6.23)％ (t=2.08,P＜0.05) and PER from (2.18±0.08) EDV/s to ( 2.68±0.11) EDV/s (t=2.13,P＜0.05) in the facilitated PCL group,while TPER,PS and PSD decreased significantly from (168±15) ms to (151±16) ms,(46.28±12.33)°to (41.92±16.75)°,(10.77±4.26)°to (9.14±1.28)° respectively(t=2.10,2.19,2.45,all P＜0.05),when compared with those in the primary PCI group.(4) The incidence of MACE in the 28 week follow-up in the facilitated PCI group(8.33％,6/72; x2 =35.05,P＜0.001) and primary PCI group (8.45％,6/71 ; x2 =34.49,P＜0.001)was significantly lower than that in the thrombolytic treatment group (54.29％,38/70).Conclusion Facilitated PCI via a transradial approach therapy might significantly inhibit left ventricular remodeling and improve the left ventricular function and systolic synchrony by the complete,persistent patency of IRA,which was superior to primary PCI or thrombolytic treatment therapy. Key words: Myocardial infarction; Myocardial contraction; Angioplasty,transluminal,percutaneous coronary; Thrombolytic therapy; Radionuclide ventriculography

Cardiovascular magnetic resonance evaluation for left ventricular diastolic function: analysis of time-volume curve

Background Although cine magnetic resonance imaging (MRI) is considered the gold standard for evaluation of left ventricular (LV) volumes, mass, and systolic function, assessment of diastolic filling is still challenging. The aim of this study was to assess the impact of LV mass on diastolic function by time-volume curve obtained from cine MRI in patients with dilated cardiomyopathy (DCM) or hypertrophic cardiomyopathy (HCM) and normal subjects. Methods Cine MRI was performed in 10 healthy controls, 11 HCM patients, and 11 DCM patients. LV end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF), LV mass, and LVESV/mass ratio were calculated by tracing endocardial and epicardial borders of LV in 8-10 short axis views. Furthermore, to assess the LV diastolic function, the peak filling rate (PFR), time to PFR (TPF), and first third filling fraction (1/3 FF) were calculated from the first derivative curve of the time-volume curve. Temporal resolution was 30 frames per R-R interval. Results

Single photon emission computed tomography myocardial perfusion imaging to detect cardiac allograft vasculopathy

Cardiac allograft vasculopathy (CAV) is a major cause of morbidity and mortality in cardiac transplant recipients. This study evaluates the usefulness of single photon emission computed tomography (SPECT) and various SPECT-derived diastolic variables to detect CAV in heart transplant patients. A retrospective review of 141 SPECT studies with corresponding coronary angiograms within 12 months was performed on 99 transplant recipients. Diastolic function was assessed using computer-derived measures of peak filling rate (PFR), time to peak filling rate (TPFR), and mean first one-third filling rate (MFR/3). Angiography identified CAV in 53 of the 141 studies (38%). Of the 53, SPECT identified 7 with reversible myocardial defects (sensitivity 13%) and stress-induced electrocardiographic evidence of ischaemia was seen in one patient (sensitivity 2%). SPECT imaging was negative in 86 of the 88 negative coronary angiograms (specificity 98%). The positive predictive value and negative predictive value were 78 and 65%, respectively. If a more stringent definition of CAV was used (≥70% stenosis), the sensitivity and specificity were unchanged (14 and 98%, respectively). There was no statistical difference in diastolic variables between patients with or without angiographic evidence of CAV in regard to PFR (3.57 ± 1.14 vs. 3.18 ± 1.21 EDV/s, P = 0.90), TPFR (149 ± 32 vs. 153 ± 43 ms, P = 0.33), or MFR/3 (1.37 ± 0.43 vs. 1.27 ± 0.42 EDV/s, P = 0.94). Adenosine stress/rest technetium-99m tetrofosmin-gated SPECT is not a sensitive test for detection of CAV in heart transplant recipients. Diastolic dysfunction, as assessed by SPECT, was not shown to be associated with development of CAV.

Baseline diastolic dysfunction as a predictive factor of trastuzumab-mediated cardiotoxicity after adjuvant anthracycline therapy in breast cancer

To evaluate the interest in assessing left ventricular diastolic function at baseline for prediction of trastuzumab-mediated cardiotoxicity (TMC) in the setting of adjuvant treatment for breast cancer. The study included 118 women presenting with HER2-positive early-stage invasive breast cancer. Patients received trastuzumab therapy over 1 year, concurrent with six cycles of docetaxel (n = 53), or following anthracycline-based chemotherapy with a cumulative dose of 300 mg/m(2) (n = 45) or 600 mg/m(2) (n = 20) of epirubicine. RNA was performed before anthracycline-based chemotherapy, before trastuzumab treatment (baseline), and every 3 months during treatment. Left ventricular ejection fraction (LVEF) and peak ejection rate (PER) were calculated to evaluate LV systolic function; peak filling rate (PFR), and time to peak filling rate (TPFR) were also calculated to evaluate LV diastolic function. Eighteen patients (15%) developed grade 1 or 2 TMC during follow-up. No significant difference was observed for age, cardiovascular risk factors, fasting blood glucose level, heart rate, systolic blood pressure, baseline LVEF, PER, and PFR between patients with and without TMC. In contrast, patients with TMC showed a longer TPFR at baseline (median [Q1-Q3]: 165 ms [149-190] vs. 142 ms [130-162]; P < 0.001). Furthermore, by logistic regression analysis, baseline TPFR >180 ms and the cumulative dose of epirubicin remained independent predictors of TMC. Patients receiving 600 mg/m(2) of epirubicin before trastuzumab showed a higher incidence of TMC (35%) than did both patients who previously received 300 mg/m(2) of epirubicin (13%) and those who received only docetaxel associated with trastuzumab (9%). Impaired left ventricular diastolic function before treatment is an independent predictor of trastuzumab-mediated cardiotoxicity. The evaluation of diastolic function could allow optimal risk stratification before the introduction of trastuzumab.

Real Time Three-Dimensional Stress Echocardiography: A New Approach for Assessing Diastolic Function

To assess the feasibility of utilizing real time three-dimensional echocardiography (RT3DE) for assessment of diastolic function during stress. Rest and stress volumes were acquired in 24 patients and parameters of diastolic function-peak ventricular filling rate (PFR) and time to peak filling rate (TPFR)-were calculated. Calculation of diastolic parameters was feasible in all patients. Resting PFR correlated with end-diastolic (EDV) and stroke volumes and inversely with TPFR (r = 0.53, 0.66, -0.5). With stress, PFR increased by 93% and TPFR decreased by 23% (P < 0.001). Stress PFR correlated with stress heart rate, EDV and stroke volume (r = 0.52, 0.50, 0.62) while TPFR correlated inversely with heart rate (r =-0.71). The change in PFR with stress correlated with the change in stroke volume (r = 0.42), while the change in TPFR correlated with the change in end-systolic volume (ESV) (r = 0.43) and inversely with the change in diastolic blood pressure (r =-0.41). Rest and stress PFR and TPFR are independent of age, gender and blood pressure and the change in PFR is independent of stress heart rate or blood pressure. E/E' correlated with stress TPFR (r = 0.72) and change in TPFR (r = 0.67) and inversely with change in PFR (r =-0.67). RT3DE can assess diastolic function during stress by detecting changes in PFR and TPFR, independent of gender, age, and blood pressure. The changes in these parameters with stress are influenced by baseline filling pressures. Larger studies are required to validate the clinical significance of these observations.

Temporal changes in diastolic function measured by volumetric CMR after ST Elevation Myocardial infarction

Method 23 patients with STEMI undergoing primary PCI were prospectively enrolled and sequential CMR imaging was performed within 96 hours of admission and at 1 month follow up. LV volumetric quantification was performed (QMass MR, Medis, Leiden, The Netherlands) with manual planimetry of the endocardial contours in all temporal phases of the contiguous short-axis slices. Systolic parameters were obtained. Diastolic CMR parameters were derived including peak filling rate (PFR) and its index normalized to end diastolic volume (NPFR), time to peak filling rate (TPFR), diastolic volume recovery (DVR80): proportion of diastole required for recovery of 80 percentage of stroke volume as well as the ratio of the biphasic early (E) and late (A) filling profiles (E/A ratio). The change in those parameters was then correlated to peak troponin-I and baseline LVEF.

Impact of diastolic dysfunction severity on global left ventricular volumetric filling - assessment by automated segmentation of routine cine cardiovascular magnetic resonance.

ObjectivesTo examine relationships between severity of echocardiography (echo) -evidenced diastolic dysfunction (DD) and volumetric filling by automated processing of routine cine cardiovascular magnetic resonance (CMR).BackgroundCine-CMR provides high-resolution assessment of left ventricular (LV) chamber volumes. Automated segmentation (LV-METRIC) yields LV filling curves by segmenting all short-axis images across all temporal phases. This study used cine-CMR to assess filling changes that occur with progressive DD.Methods115 post-MI patients underwent CMR and echo within 1 day. LV-METRIC yielded multiple diastolic indices - E:A ratio, peak filling rate (PFR), time to peak filling rate (TPFR), and diastolic volume recovery (DVR80 - proportion of diastole required to recover 80% stroke volume). Echo was the reference for DD.ResultsLV-METRIC successfully generated LV filling curves in all patients. CMR indices were reproducible (≤ 1% inter-reader differences) and required minimal processing time (175 ± 34 images/exam, 2:09 ± 0:51 minutes). CMR E:A ratio decreased with grade 1 and increased with grades 2-3 DD. Diastolic filling intervals, measured by DVR80 or TPFR, prolonged with grade 1 and shortened with grade 3 DD, paralleling echo deceleration time (p < 0.001). PFR by CMR increased with DD grade, similar to E/e' (p < 0.001). Prolonged DVR80 identified 71% of patients with echo-evidenced grade 1 but no patients with grade 3 DD, and stroke-volume adjusted PFR identified 67% with grade 3 but none with grade 1 DD (matched specificity = 83%). The combination of DVR80 and PFR identified 53% of patients with grade 2 DD. Prolonged DVR80 was associated with grade 1 (OR 2.79, CI 1.65-4.05, p = 0.001) with a similar trend for grade 2 (OR 1.35, CI 0.98-1.74, p = 0.06), whereas high PFR was associated with grade 3 (OR 1.14, CI 1.02-1.25, p = 0.02) DD.ConclusionsAutomated cine-CMR segmentation can discern LV filling changes that occur with increasing severity of echo-evidenced DD. Impaired relaxation is associated with prolonged filling intervals whereas restrictive filling is characterized by increased filling rates.