Prognostic Value of Cardiac Time Intervals by Tissue Doppler Imaging M-Mode in Patients With Acute ST-Segment–Elevation Myocardial Infarction Treated With Primary Percutaneous Coronary Intervention

Association between cardiac time intervals and incident heart failure after acute coronary syndrome

BACKGROUND

Cardiac time intervals are sensitive markers of myocardial dysfunction that predispose to heart failure (HF). We aimed to investigate the association between cardiac time intervals and HF in patients with acute coronary syndrome (ACS).

METHODS

This study included 386 ACS patients treated with percutaneous coronary intervention (PCI). Patients underwent an echocardiography examination a median of two days after PCI. Cardiac time intervals including isovolumic relaxation time (IVRT), isovolumic contraction time (IVCT), and systolic ejection time (ET), and myocardial performance index (MPI) were obtained by tissue Doppler echocardiography. The outcome was incident HF.

RESULTS

During follow-up (median 4.3, IQR:1.0-6.7 years), 140 (36%) developed HF. In unadjusted analyses, IVRT was not associated with HF (HR 1.02 (0.95-1.10), p = 0.61, per 10ms increase), and neither was IVCT (HR 0.07 (0.95-1.22), p = 0.26, per 10ms increase). Increasing MPI was associated with a higher risk of HF (HR 1.20 (1.08-1.34), P = 0.001, per 0.1 increase), and so was decreasing ET (HR 1.13 (1.07-1.18), P < 0.001 per 10ms decrease). After multivariable adjustment for cardiovascular risk factors, MPI (HR 1.13 (1.01-1.27), P = 0.034) and ET (HR 1.09 (1.01-1.17), P = 0.025) remained significantly associated with incident HF. LVEF modified the association between ET and HF (p for interaction = 0.002), such that ET was associated with HF in patients with LVEF ≥ 36% (HR = 1.15 (1.06-1.24), P = 0.001, per 10ms decrease).

CONCLUSION

In patients admitted with ACS, shortened ET and higher MPI were independently associated with an increased risk of incident HF. Additionally, ET was associated with incident HF in patients with LVEF above 36%.

Ratio of early transmitral inflow velocity to early diastolic strain rate predicts atrial fibrillation following acute myocardial infarction

The ratio of early transmitral filling velocity to early diastolic strain rate (E/SRe) has been proposed as a new non-invasive measurement of left ventricular filling pressure. We aimed to investigate the ability of E/SRe to predict atrial fibrillation (AF) after ST-elevation myocardial infarction (STEMI). This was a prospective cohort study of patients (n = 369) with STEMI. Patients underwent an echocardiographic examination a median of two days after pPCI. By echocardiography, transmitral early filling velocity (E) was measured by pulsed-wave Doppler, and early diastolic strain rate (SRe) was measured by speckle tracking of the left ventricle. E was indexed to SRe and the early myocardial relaxation velocity (e') to obtain the E/SRe and E/e', respectively. The endpoint was new-onset AF. During follow-up (median 5.6 years, IQR: 5.0-6.1 years), 23 (6%) of the 369 patients developed AF. In unadjusted analyses, both E/SRe and E/e' were significantly associated with AF [E/SRe: HR = 1.06; (1.03-1.10); p < 0.001, per 10 increase] and [E/e': HR = 1.11 (1.05-1.17); p < 0.001, per 1 increase] and had equal Harrell's C-statistic of 0.71. However, only E/SRe remained an independent predictor after multivariable adjustments for clinical and echocardiographic parameters [E/SRe: HR = 1.06 (1.00-1.11); p = 0.044, per 10 increase]. E/SRe was further significantly associated with AF in patients with E/e' < 14 HR = 1.09 (1.01-1.17); p = 0.030, per 10 increase), also after multivariable adjustments. E/SRe is an independent predictor of AF in STEMI patients, even in subjects with seemingly normal filling pressure.

Prognostic value of myocardial performance index in individuals with type 1 and type 2 diabetes: Thousand&1 and Thousand&2 studies

AIMS

Cardiovascular disease (CVD) is the leading cause of mortality and morbidity in type 1 (T1D) and type 2 diabetes (T2D). Despite diabetes affects the myocardium, risk prediction models do not include myocardial function parameters. Myocardial performance index (MPI) reflects left ventricular function. The prognostic value of MPI has not been evaluated in large-scale diabetes populations.

METHODS AND RESULTS

We evaluated two prospective cohort studies: Thousand&1 (1093 individuals with T1D) and Thousand&2 (1030 individuals with T2D). Clinical data, including echocardiography, were collected at baseline. We collected follow-up data from national registries. We defined major adverse cardiovascular events (MACE) as incident events of hospital admission for acute coronary syndrome, heart failure, stroke, or all-cause mortality. For included individuals (56% male, 54 ± 15 years, MPI 0.51 ± 0.1, 63% T1D), follow-up was 100% after median of 5.3 years (range: 4.8-6.3). MPI was associated with MACE (HR 1.2, 95%CI 1.0-1.3, P = 0.012, per 0.10-unit increase) and heart failure (HR 1.3, 95%CI 1.1-1.6, P = 0.005, per 0.10-unit increase) after adjusting for clinical and echocardiographic variables. MPI predicted MACE and heart failure better in T1D than T2D (P = 0.031 for interaction). MPI added discriminatory power to the Steno T1 Risk Engine, based on clinical characteristics, in predicting MACE [area under the curve (AUC) from 0.77 to 0.79, P = 0.030] and heart failure (AUC from 0.77 to 0.83, P = 0.009) in T1D.

CONCLUSION

MPI is independently associated with MACE and heart failure in T1D but not T2D and improves prediction in T1D. Echocardiographic assessment in T1D may enhance risk prediction.

Age- and sex-based normal reference ranges of the cardiac time intervals: the Copenhagen City Heart Study

BACKGROUND

Color tissue Doppler imaging (TDI) M-mode can be used to measure the cardiac time intervals including the isovolumic contraction time (IVCT), the left ventricular ejection time (LVET), the isovolumic relaxation time (IVRT), and the combination of all the cardiac time intervals in the myocardial performance index (MPI) defined as [(IVCT + IVRT)/LVET]. The aim of this study was to establish normal age- and sex-based reference ranges for the cardiac time intervals.

METHODS AND RESULTS

A total of 1969 participants free of cardiovascular diseases and risk factors from the general population with limited age range underwent an echocardiographic examination including TDI. The median age was 46 years (25th-75th percentile: 33-58 years), and 61.5% were females. In the entire study population, the IVCT was observed to be 40 ± 10 ms [95% prediction interval (PI) 20-59 ms], the LVET 292 ± 23 ms (95% PI 248-336 ms), the IVRT 96 ± 19 ms (95% PI 59-134 ms) and MPI 0.47 ± 0.09 (95% PI 0.29-0.65). All the cardiac time intervals differed significantly between females and males. With increasing age, the IVCT increased in females, but not in males. The LVET did not change with age in both sexes, while the IVRT increased in both sexes with increasing age. Furthermore, we developed regression equations relating the heart rate to the cardiac time intervals and age- and sex-based normal reference ranges corrected for heart rate.

CONCLUSION

In this study, we established normal age- and sex-based reference ranges for the cardiac time intervals. These normal reference ranges differed significantly with sex.

Changes in cardiac time intervals over a decade and the risk of incident heart failure: The Copenhagen City heart study

BACKGROUND

The cardiac time intervals include the isovolumic contraction time (IVCT), the left ventricular ejection time (LVET), the isovolumic relaxation time (IVRT) and the combination of all the cardiac time intervals in the myocardial performance index (MPI) (defined as [(IVCT+IVRT)/LVET)]. Whether the cardiac time intervals change over time and which clinical factors that accelerate these changes is not well-established. Additionally, whether these changes are associated with subsequent heart failure (HF), remains unknown.

METHODS

We investigated participants from the general population (n = 1064) who had an echocardiographic examination including color tissue Doppler imaging performed in both the 4th and 5th Copenhagen City Heart Study. The examinations were performed 10.5 years apart.

RESULTS

The IVCT, LVET, IVRT and MPI increased significantly over time. None of the investigated clinical factors were associated with increase in IVCT. Systolic blood pressure (standardized β= - 0.09) and male sex (standardized β= - 0.08) were associated with an accelerated decrease in LVET. Age (standardized β=0.26), male sex (standardized β=0.06), diastolic blood pressure (standardized β=0.08), and smoking (standardized β=0.08) were associated with an increase in IVRT, while HbA1c (standardized β= - 0.06) was associated with a decrease in IVRT. Increasing IVRT over a decade was associated with an increased risk of subsequent HF in participants aged <65 years (per 10 ms increase: HR 1.33; 95%CI (1.02-1.72), p = 0.034).

CONCLUSION

The cardiac time increased significantly over time. Several clinical factors accelerated these changes. An increase in IVRT was associated with an increased risk of subsequent HF in participants aged <65 years.

Ventricular Function and Cardio-Ankle Vascular Index in Patients With Pulmonary Artery Hypertension

Aim

This study aims to evaluate the left ventricle (LV) systolic and diastolic function in patients with idiopathic pulmonary arterial hypertension (IPAH) and its correlation with systemic arterial stiffness assessed by cardio-ankle vascular index (CAVI).

Patient and methods

We included 37 patients with IPAH and 20 healthy people matched by age. All patients were assessed: vital signs, 6-minute walk test, NT-proBNP level, the CAVI, the right ventricular (RV) and LV function parameters, including ejection time (ET), tissue speckle-tracking values - global longitudinal strain (GLS) and strain rate (SR).

Results

The groups were matched by age, gender, BMI, office SBP and DBP. Patients with IPAH had higher heart rate, NT-proBNP level and lower ferritin level, GFR (CKD-EPI), SaO2 than healthy people. The mean CAVIleft was higher in IPAH patients than in the control group- 8.7±1.1 vs 7.5±0.9, P=0.007. Healthy people had significantly less E/e' and lower IVRT. LVET and RVET were shorter in IPAH patients. Patients with IPAH had mean LVGLS -(-17.6±4.8%) and 35.1% of them were with LVGLS ≤16% compared to healthy people -(-21.8±1.4%) and 0%, respectively. LVSR was significant less in IPAH patients, but in the normal range. We found significant correlations of CAVI with age, history of syncope, bilirubin, uric acid, total cholesterol, cardiac output, cardiac index, RVET, LVET and E/A. Multiple linear regression confirmed the independent significance for age (β=0.083±0.023, CI 0.033-0.133) and RVET (β=-0.018±0.005, CI -0.029 to -0.008) only. The risk to have CAVI ≥8 increased in 5.8 times in IPAH patients with RVET <248 ms (P=0.046). CAVI did not correlate with LVGLS and LVSR.

Conclusion

Significant worse systolic and diastolic LV functions were stated in pulmonary hypertensive patients compared to the control group. No LV GLS, no LV SR had significant associations with arterial stiffness evaluated by CAVI.

Use of proposed systolic and myocardial performance indices derived from simultaneous ECG and PCG recordings to assess cardiac function in healthy Beagles

Background and Aim:

Cardiac time intervals (CTIs) can provide important information on the electrical and mechanical properties of the heart. We hypothesized that cardiac function can be described using the combined power of electrocardiography (ECG) and phonocardiography (PCG) signals. This study aimed to (1) validate a novel custom device in measuring CTI parameters; (2) compare CTI parameters with a commercially available device and standard transthoracic echocardiography (STE); and (3) compare calculated systolic performance index (SPI) and myocardial performance index (MPI) with Tei index from the STE.

Materials and Methods:

This study determined CTIs based on simultaneous ECG and PCG recordings in 14 healthy Beagle dogs using the custom-built device. These CTI parameters were compared with a commercially available device (Eko DUO ECG + Digital Stethoscope; Eko DUO) and the STE. Agreement of CTI parameters between the custom device and the commercially available device or STE was evaluated. Calculated SPI and MPI based on Wigger’s diagram were proposed, compared with SPI and Tei index, and correlated with STE parameters.

Results:

We found that the ECG and PCG parameters measured from the custom-built device did not differ from the commercially available device and the STE. By combining ECG and PCG signals, we established CTI parameters in healthy dogs including indices for systolic function (SPI: QS1/S1S2) and global cardiac function {F1 ([QS1+S2]/S1S2), F2 ([RS1+S2]/S1S2), and F3 (RS1 + [QS2-QT]/S1S2)}. The SPI, F2, and F3 were comparable with echocardiographic parameters describing systolic (Pre-ejection period/left ventricular ejection time [LVET]) and Tei index ([MCOdur-LVET]/LVET), respectively. Only SPI and F3 were correlated significantly with MCOdur and heart rate, respectively.

Conclusion:

We have validated the use of the custom-built device to describe CTIs that are comparable to the commercially available device and STE in healthy Beagles. The proposed SPI and MPI derived from CTI parameters can be useful in clinical practice to describe the cardiac function, especially in areas where access to STE is constrained.

Can Seismocardiogram Fiducial Points Be Used for the Routine Estimation of Cardiac Time Intervals in Cardiac Patients?

The indexes of cardiac mechanics can be derived from the cardiac time intervals, CTIs, i.e., the timings among the opening and closure of the aortic and mitral valves and the Q wave in the ECG. Traditionally, CTIs are estimated by ultrasound (US) techniques, but they may also be more easily assessed by the identification of specific fiducial points (FPs) inside the waveform of the seismocardiogram (SCG), i.e., the measure of the thorax micro-accelerations produced by the heart motion. While the correspondence of the FPs with the valve movements has been verified in healthy subjects, less information is available on whether this methodology may be routinely employed in the clinical practice for the monitoring of cardiac patients, in which an SCG waveform distortion is expected because of the heart dysfunction. In this study we checked the SCG shape in 90 patients with myocardial infarction (MI), heart failure (HF), or transplanted heart (TX), referred to our hospital for rehabilitation after an acute event or after surgery. The SCG shapes were classified as traditional (T) or non-traditional (NT) on whether the FPs were visible or not on the basis of nomenclature previously proposed in literature. The T shape was present in 62% of the patients, with a higher ∓ prevalence in MI (79%). No relationship was found between T prevalence and ejection fraction (EF). In 20 patients with T shape, we checked the FPs correspondence with the real valve movements by concomitant SCG and US measures. When compared with reference values in healthy subjects available in the literature, we observed that the Echo vs. FP differences are significantly more dispersed in the patients than in the healthy population with higher differences for the estimation of the mitral valve closure (−17 vs. 4 ms on average). Our results indicate that not every cardiac patient has an SCG waveform suitable for the CTI estimation, thus before starting an SCG-based CTI monitoring a preliminary check by a simultaneous SCG-US measure is advisable to verify the applicability of the methodology.

Duration of early systolic lengthening: prognostic potential in the general population

BACKGROUND

When the left ventricle pressure rises during early systole, myocardial fibres with reduced contractility tend to stretch instead of shortening. This interval is known as duration of early systolic lengthening (DESL). We sought to investigate if DESL provides prognostic information on cardiovascular events.

METHODS AND RESULTS

In this prospective study we included 1210 participants from a low-risk general population who underwent speckle tracking echocardiography (men 41%, mean age 56 years, SD 16). Primary endpoints were incident heart failure (HF), myocardial infarction (MI), and cardiovascular death (CVD). We defined DESL as time from onset of Q-wave on the electrocardiogram to peak positive systolic strain. In addition, we assessed the ratio between DESL and duration of cardiac systole, DESLsystole.During median follow-up of 16 years, 90 (7%) developed HF, 50 (4%) MI, and 70 (6%) experienced CVD. Both DESL [hazard ratio (HR) 1.58 95%CI 1.16-2.15, P = 0.004 per 10 ms increase] and DESLsystole (HR 1.74 95%CI 1.24-2.47, P = 0.001 per 1% increase) were predictors of HF. Similarly, DESL (HR 1.40 95%CI 1.09-1.78, P = 0.007 per 10 ms increase) and DESLsystole (HR 1.58 95%CI 1.01-2.49, P = 0.047 per 1% increase) were predictors of MI. No associations were found with CVD. After adjusting for clinical and echocardiographic parameters, the associations remained significant. DESLsystole was superior to systolic echocardiographic parameters for predicting HF (P = 0.012).

CONCLUSION

DESL and the novel index of DESLsystole provide independent and novel prognostic information on the risk of HF and MI in the general population. Evaluation of DESL should be explored in future echocardiographic studies.

Layer-specific global longitudinal strain obtained by speckle tracking echocardiography for predicting heart failure and cardiovascular death following STEMI treated with primary PCI

The aim of this study was to evaluate layer-specific global longitudinal strain (GLS), obtained by speckle tracking, in predicting outcomes following ST-segment elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention (pPCI). Echocardiography, including layer-specific GLS, was performed at median two days after the STEMI in a prospective study of STEMI patients treated with pPCI between September 2006 and December 2008. The outcome was the composite of heart failure hospitalization and/or cardiovascular death (HF/CVD). A total of 349 patients were included. Mean age was 62.2 ± 11.5 years, 76% were male, and mean ejection fraction (LVEF) was 46 ± 9. Seventy-seven (22%) patients developed HF/CVD during median follow-up 5.4 years. Patients with HF/CVD had lower absolute values for all GLS-layers: endocardial (GLS_Endo) 11.4%vs 14.5% (p < 0.001), midmyocardial (GLS_Mid) 9.8% vs 12.5% (p < 0.001) and epicardial (GLS_Epi) 8.5% vs 10.9% (p < 0.001). In unadjusted analysis, all layers were significant predictors of HF/CVD; hazard ratio (HR) per 1% decrease for GLS_Endo: HR 1.18 (95%CI 1.11-1.25), GLS_Mid: HR 1.22 (95%CI 1.14-1.30) and GLS_Epi: HR 1.26 (95%CI 1.16-1.36), p < 0.0001 for all. The risk of HF/CVD increased incrementally with increasing tertiles for all layers, being more than three times higher in 3rd tertile compared to 1st tertile. In multivariable models, including baseline clinical and echocardiographic parameters, only GLS_Mid and GLS_Epi remained independent predictors of HF/CVD. Global longitudinal strain obtained from all myocardial layers were significant predictors of incident HF and CVD following STEMI, however, only GLS_Mid and GLS_Epi remained independent predictors after multivariable adjustment.

Kidney function and the prognostic value of myocardial performance index

A decreased glomerular filtration rate (GFR) is a risk factor for cardiovascular disease even after adjustment for conventional risk factors. The myocardial performance index (MPI) is defined as (isovolumetric relaxation time (IVRT) + isovolumetric contraction time (IVCT))/ejection time (ET). It has been shown to be an independent predictor of cardiovascular events. We hypothesized the MPI could prove valuable for assessing cardiac risk in subjects of the general population with decreased estimated GFR (eGFR). MPI was measured in 1915 subjects from a large general population prospective cohort study using color tissue Doppler imaging (TDI) M-mode through the mitral valve. We compared the prognostic capabilities of the MPI between subjects with eGFR ≥ 75 mL/min/1.73 m² and subjects with eGFR < 75 mL/min/1.73 m² using multivariable adjusted Cox regression models. The composite endpoint was heart failure, myocardial infarction or cardiovascular death. Mean age was 58 years (SD 16.2), 58% were women, 42% had hypertension and 8.3% diabetes. During a median follow-up time of 12.4 years [IQR 10.6-12.7 years] 269 participants reached the combined endpoint. eGFR modified the prognostic capability of MPI (p-value for interaction < 0.001): After multivariable adjustment, MPI remained an independent predictor of the composite endpoint only in participants with eGFR < 75 mL/min/1.73 m²: HR 1.18 (95% CI 1.02-1.38), p = 0.03, vs. in subjects with eGFR ≥ 75 mL/min/1.73 m²: HR 1.14 (95% CI 0.94-1.39), p = 0.17. These results suggest the MPI could be particularly valuable for identifying elevated cardiac risk in individuals from the general population with decreased eGFR.

The prognostic value of Tei index in acute myocardial infarction: a systematic review

Background

Echocardiographic evaluation of left ventricular ejection fraction (LVEF) is used in the risk stratification of patients with an acute myocardial infarction (AMI). However, the prognostic value of the Tei index, an alternative measure of global cardiac function, in AMI patients is not well established.

Methods

We conducted a systematic review, using MEDLINE and EMBASE, to evaluate the prognostic value of the Tei index in predicting adverse outcomes in patients presenting with AMI. The data was collected and narratively synthesised.

Results

A total of 16 studies were including in this review with 2886 participants (mean age was 60 years from 14 studies, the proportion of male patients 69.8% from 14 studies). Patient follow-up duration ranged from during the AMI hospitalisation stay to 57.8 months. Tei index showed a significant association with heart failure episodes, reinfarction, death and left ventricular thrombus formation in 14 out of the 16 studies. However, in one of these studies, Tei index was only significantly predictive of cardiac events in patients where LVEF was <40%. In two further studies, Tei index was not associated with predicting adverse outcomes once LVEF, left ventricular end-systolic volume index and left ventricular early filling time was taken into consideration. In the two remaining studies, there was no prognostic value of Tei index in relation to patient outcomes.

Conclusions

Tei index may be an important prognostic marker in AMI patients, however, more studies are needed to better understand when it should be used routinely within clinical practice.

Left ventricular systolic ejection time is an independent predictor of all-cause mortality in heart failure with reduced ejection fraction

AIMS

Colour tissue Doppler imaging (TDI) M-mode through the mitral leaflet is an easy and precise method to obtain cardiac time intervals including isovolumic contraction time (IVCT), isovolumic relaxation time (IVRT) and systolic ejection time (SET). The myocardial performance index (MPI) is defined as [(IVCT + IVRT)/SET]. Whether cardiac time intervals obtained by the TDI M-mode method can be used to predict outcome in patients with heart failure with reduced ejection fraction (HFrEF) remains unknown.

METHODS AND RESULTS

A total of 997 patients with HFrEF (mean age 67 ± 11 years, 74% male) underwent an echocardiographic examination including TDI. During a median follow-up of 3.4 years (interquartile range 1.9-4.8 years), 165 (17%) patients died. The risk of mortality increased by 9% per 10 ms decrease in SET [per 10 ms decrease: hazard ratio (HR) 1.09, 95% confidence interval (CI) 1.06-1.13; P < 0.001]. The association remained significant even after multivariable adjustment for clinical and echocardiographic parameters (per 10 ms decrease: HR 1.06, 95% CI 1.01-1.11; P = 0.030). The MPI was a significant predictor in an unadjusted model (per 0.1 increase: HR 3.06, 95% CI 1.16-8.06; P = 0.023). However, the association did not remain significant after multivariable adjustment. No significant associations between IVCT or IVRT and mortality were found in unadjusted nor adjusted models. Additionally, SET provided incremental prognostic information with regard to predicting mortality when added to established clinical predictors of mortality in patients with HFrEF.

CONCLUSION

In patients with HFrEF, SET provides independent and incremental prognostic information regarding all-cause mortality.

Myocardial performance index is associated with cardiac computed tomography findings in patients with suspected coronary artery disease

BACKGROUND

Studies suggest cardiac time intervals to be associated with cardiac ischemia. A novel method to assess cardiac time intervals by tissue Doppler echocardiography has been proposed. Cardiac time intervals can assess the myocardial performance index (MPI), which quantifies the proportion of time spent contributing effective myocardial work. We hypothesized that MPI associates with coronary artery lesions detected by cardiac computed tomography (CT) in patients suspected of coronary artery disease (CAD).

METHODS

We investigated patients referred for cardiac CT under suspicion of CAD who had an echocardiogram performed. Curved m-mode tissue Doppler imaging was used to measure cardiac time intervals and MPI. The outcome was coronary artery lesions, defined as a calcium score > 400 and/or coronary artery stenosis (>70% luminal narrowing). Logistic regression was applied with multivariable models including: (a) SCORE chart risk factors and (b) SCORE chart risk factors, body mass index, dyslipidemia, familial history of CAD, diabetes mellitus, LVEF, and left ventricular mass index.

RESULTS

Of 404 patients, 41 (10%) had a coronary artery lesion. Overall, 42% were male, mean age was 58 years, and LVEF was 58%. Patients with coronary artery lesions exhibited higher MPI than those without (0.52 vs. 0.44, P < .001). MPI associated with coronary artery lesions in unadjusted analyses (OR = 1.69 [1.30-2.19], per 0.1 increase), and this association persisted when adjusted for SCORE chart risk factors (OR = 1.55 [1.16-2.07], P = .003, per 0.1 increase), and additional risk factors (OR = 1.64 [1.11-2.41], P = .013, per 0.1 increase).

CONCLUSION

Curved m-mode-derived MPI is associated with coronary artery lesions detected by cardiac CT in suspected CAD patients.

Left ventricular output indices in hospitalized heart failure: when "simpler" may not mean "better"

Assessment of left ventricular (LV) output in hospitalized patients with heart failure (HF) is important to determine prognosis. Although echocardiographic LV ejection fraction (EF) is generally used to this purpose, its prognostic value is limited. In this investigation LV-EF was compared with other echocardiographic per-beat measures of LV output, including non-indexed stroke volume (SV), SV index (SVI), stroke distance (SD), ejection time (ET), and flow rate (FR), to determine the best predictor of all-cause mortality in patients hospitalized with HF. A final cohort of 350 consecutive patients hospitalized with HF who underwent echocardiography during hospitalization was studied. At a median follow-up of 2.7 years, 163 patients died. Non-survivors at follow-up had lower SD, SVI and SV, but not ET, FR and LV-EF than survivors. At multivariate analysis, only age, systolic blood pressure, chronic kidney disease, chronic obstructive pulmonary disease, use of angiotensin-converting enzyme inhibitors/angiotensin receptor blockers and SVI remained significantly associated with outcome [HR for SVI 1.13 (1.04-1.22), P = 0.003]. In particular, for each 5 ml/m² decrease in SVI, a 13% increase in risk of mortality for any cause was observed. SVI is a powerful prognosticator in HF patients, better than other per-beat measures, which may be simpler but partial or incomplete descriptors of LV output. SVI, therefore, should be considered for the routine echocardiographic evaluation of patients hospitalized with HF to predict prognosis.

A Validated Echocardiographic Risk Model for Predicting Outcome Following ST-segment Elevation Myocardial Infarction

Many echocardiographic measures have been proposed as potential predictors of outcome following ST-elevation myocardial infarction (STEMI). We hypothesized that combining multiple echocardiographic measures in a risk model provides more prognostic information than individual echocardiographic measures. We prospectively included 373 STEMI patients which constituted our derivation cohort. We also identified 298 STEMI patients from a clinical registry that constituted our validation cohort. Echocardiogram was performed at a median of 2 days after infarction. The echocardiogram consisted of conventional and advanced measures. The end point was a composite of heart failure and/or cardiovascular death. During a median follow-up of 5.4 years, we observed 80 events in our derivation cohort. A stepwise backward Cox regression including all echocardiographic parameters identified global longitudinal strain, wall motion score index (WMSI), E/e', and E/global strain rate e (E/GLSRe) as significant predictors of outcome. A Classification and Regression Tree analysis outlined a risk model with WMSI, GLSRe, and E/e' as key echocardiographic parameters. Patients with WMSI ≥ 2.22 were at high risk, patients with WMSI < 2.22, GLSRe < 0.82s^-1 and E/e'≥7.6 at intermediate risk, and patients with WMSI < 2.22 and GLSRe ≥ 0.82s^-1 or GLSRe < 0.82s^-1 and E/e' < 7.6 at low risk of heart failure and/or cardiovascular death. When compared with the low-risk group, an incremental risk was observed (intermediate group: HR = 2.52 [1.24;5.11], p = 0.011; high-risk group: HR = 4.37 [1.40;13.66], p = 0.011). The risk model was validated in the validation cohort (C-statistic: 0.71). In conclusion, we devised an echocardiographic risk model for STEMI patients suggesting advanced and conventional measures of systolic function and filling pressures to be important for the prognosis.

Myocardial performance index by tissue Doppler echocardiography predicts adverse events in patients with atrial fibrillation

AIMS

The prognostic value of myocardial performance index (MPI) has not yet been assessed in patients with atrial fibrillation (AF). The aim of this study was to evaluate the prognostic value of MPI by tissue Doppler imaging (TDI) M-mode in AF patients.

METHODS AND RESULTS

Echocardiograms from 210 patients with AF during examination were analysed offline. Patients with known heart failure (HF) were excluded. Time intervals were measured using an M-mode line through the mitral valve leaflets to provide a colour diagram of the mitral leaflet movement so all time intervals could be measured from one cardiac cycle. MPI was calculated as the sum of isovolumic relaxation time and isovolumic contraction time divided by the ejection time [(IVRT+IVCT)/ET]. During a median follow-up of 2.4 years, 84 patients (40%) reached the combined endpoint of major adverse cardiovascular events (MACE), being all-cause mortality, HF, myocardial infarction, or stroke. Increasing MPI was significantly associated with an increased risk of MACE, and the risk increased with 20% per 0.1 increase in MPI [hazard ratio (HR) 1.20, 95% confidence interval (CI) 1.10-1.32; P < 0.001]. Increasing MPI was also significantly associated with a lower left ventricular ejection fraction (LVEF) (P < 0.001). Nevertheless, MPI remained an independent predictor even after adjustment for age, sex, diabetes mellitus, left atrial volume, and LVEF (HR 1.12, 95% CI 1.01-1.25; P = 0.038).

CONCLUSION

Increasing MPI was significantly associated with increased risk of MACE and remained an independent predictor after multivariable adjustment. This demonstrates that the MPI obtained by TDI M-mode might be useful in assessing cardiac function in AF patients with ongoing arrhythmia during examination.

Coronary microvascular dysfunction is associated with cardiac time intervals in women with angina and no obstructive coronary artery disease: An iPOWER substudy

BACKGROUND

Coronary microvascular dysfunction (CMD) may cause angina in the absence of obstructive coronary artery disease (CAD) and increases the risk of future adverse cardiovascular events. Transthoracic Doppler echocardiography (TTDE) with pharmacological stress can assess coronary flow velocity reserve (CFVR), a measure of coronary microvascular function. However, simpler methods would be preferable for diagnosing CMD. Therefore, we examined the relationship between CFVR and cardiac time intervals measured by TTDE in a cohort of women with angina and no obstructive CAD.

METHODS

In a prospective cohort study, we included 389 women with angina, left ventricular ejection fraction > 45%, and no obstructive CAD. CMD was defined as CFVR < 2.0. The study population was divided into three groups according to cutoff values of CFVR < 2, 2 ≤ CFVR ≤ 2.5, and CFVR > 2.5. Isovolumic contraction time (IVCT), ejection time (ET), and isovolumic relaxation time (IVRT) were measured by tissue Doppler M-mode, and the myocardial performance index (MPI = (IVCT + IVRT)/ET) was calculated.

RESULTS

Coronary microvascular dysfunction was associated with increasing age, hypertension, higher resting heart rate, and lower diastolic blood pressure. Moreover, CMD was associated with higher E/e' ratio (P = 0.002) and longer IVCT (P < 0.001), higher MPI (P < 0.001) and shorter ET (P = 0.002), but not with IVRT or conventional measures of left ventricular geometry, mass, and function. In multivariable analysis, longer IVCT (P < 0.001) and higher MPI (P = 0.002) remained associated with CMD.

CONCLUSION

In women with angina and no obstructive CAD, CMD is associated with longer IVCT and higher MPI indicating a link between CMD and subtle alternations of systolic and combined measures of cardiac time intervals.

The cardiac isovolumetric contraction time is an independent predictor of incident atrial fibrillation and adverse outcomes following first atrial fibrillation event in the general population

Aims

Colour tissue Doppler imaging (TDI) M-mode through the mitral leaflet is an easy and precise method to obtain cardiac time intervals including the isovolumic contraction time (IVCT), isovolumic relaxation time (IVRT), and ejection time (ET). The myocardial performance index (MPI) was defined as [(IVCT + IVRT)/ET]. Our aim was to investigate if cardiac time intervals can be used to predict atrial fibrillation (AF) in the general population.

Methods and results

A total of 1915 participants from the general population underwent a health examination including TDI echocardiography. The primary endpoint was AF, and the secondary endpoint was complicated AF as assessed by the occurrence of either stroke or heart failure (HF) after the diagnosis of AF. Participants with known AF were excluded (n = 54). During a median follow-up of 11 years, 166 participants (9%) were diagnosed with AF and of these 44 participants (27%) developed HF or stroke. Assessing the association between IVCT and incident AF, the risk increased with 27% per 10 ms increase in IVCT [per 10 ms increase: hazard ratio (HR) 1.27, 95% confidence interval (CI) (1.17–1.38); P &lt; 0.001]. The association remained significant after multivariable adjustment [per 10 ms increase: HR 1.22, 95% CI (1.09–1.35); P &lt; 0.001]. No associations between the IVRT, ET, MPI, and AF remained significant after multivariable adjustment. The IVCT also predicted complicated AF and the association remained significant even after multivariable adjustment [per 10 ms increase: HR 1.39, 95% CI (1.06–1.81); P = 0.015].

Conclusion

In the general population, the IVCT provides novel and independent prognostic information on the long-term risk of AF. Additionally, the IVCT can identify persons in risk of complicated AF.

Multimodality imaging in ischaemic heart failure

In heart failure, extensive evaluation with modern non-invasive imaging modalities is needed to assess causes, pathophysiology, and haemodynamics, to determine prognosis and consider therapeutic options. This systematic evaluation includes a stepwise assessment of left ventricular size and function, the presence and severity of coronary artery disease, mitral regurgitation, pulmonary hypertension, right ventricular dilation and dysfunction, and tricuspid regurgitation. Based on this imaging-derived information, the need for specific therapies besides optimised medical therapy can be determined. The need for revascularisation, implantation of an implantable cardiac defibrillator, and mitral or tricuspid valve repair or replacement, can be (partially) guided by non-invasive imaging. Importantly, randomised controlled trials on the use of non-inasive imaging to guide therapy are scarce in this field and most non-pharmacological therapies are based on expert-consensus, but whenever trials are available, they will be addressed in this paper.

Post-systolic shortening: normal values and association with validated echocardiographic and invasive measures of cardiac function

Post-systolic shortening (PSS) does not contribute to the ejection of blood and may inhibit diastolic filling. We determined normal values of PSS in healthy subjects and investigated associations with echocardiographic and invasive measures of systolic and diastolic function. We prospectively analyzed participants from the general population (n = 620, mean age 47 ± 14 years) with no cardiovascular disease. Participants underwent echocardiography, including speckle tracking assessment of the post-systolic index (PSI), strain and time. We defined the PSI as: 100 × [(peak global longitudinal strain - peak systolic longitudinal strain)/(peak global longitudinal strain)]. We also included stable patients (n = 44) referred for left ventricle (LV) catheterization and echocardiography. Normal values: median PSI 2.0% (IQR 0.7, 4.8), post-systolic strain 0.4% (IQR 0.2, 0.8) and post-systolic time 22.6 ms (IQR 10.7, 40.8). Sex modified the relationship between PSI and age (P interaction = 0.037), such that PSI increased with age in women but not in men. PSI was associated with diastolic function (e', E/e' and E/A) (P < 0.05 for all), but not with LV ejection fraction (P = 0.08). PSI was associated with invasively measured LV pressure decline in early diastole, dP/dt min ([Formula: see text] = 0.12, P = 0.010), but not with LV pressure rise in early systole, dP/dt max ([Formula: see text]= - 0.05, P = 0.30). A PSI > 5% had 82% specificity and 99% sensitivity for identifying impaired LV systolic and/or diastolic function. Normal values of PSS are modified by sex. The PSI is associated with most validated echocardiographic and invasive measures of cardiac systolic and diastolic function.

Prognostic importance of mechanical dyssynchrony in predicting heart failure development after ST-segment elevation myocardial infarction

The aim of this study is to assess the prognostic value of mechanical dyssynchrony defined as the standard deviation of the time to peak longitudinal strain (SD T2P LS) in predicting the development of heart failure (HF) after an ST-segment elevation myocardial infarction (STEMI). Three hundred and seventy-three patients were admitted with STEMI and treated with primary percutaneous coronary intervention. Left ventricular (LV) mechanical dyssynchrony was examined through speckle tracking echocardiography and defined as SD T2P LS. The association with the outcome of HF hospitalization was assessed using Cox proportional hazard models. During a median follow-up of 5.12 years, 144 patients (38.6%) were admitted due to HF. Worse dyssynchrony was associated with the outcome in unadjusted and multivariable analysis (multivariable hazard ratio 1.05, 95% confidence interval 1.00-1.10, p-value 0.039, per 10 ms increase), but not after further adjustment for LV ejection fraction (LVEF), E/e' and global longitudinal strain (GLS) (hazard ratio 1.01, 95% confidence interval 1.00-1.07, p-value 0.71, per 10 ms increase), nor in a model only adjusting for GLS (hazard ratio 1.01, 95% confidence interval 1.00-1.06, p-value 0.61, per 10 ms increase). These findings were reproduced in a competing risk analysis treating all-cause mortality as a competing risk. LV mechanical dyssynchrony, as assessed by SD T2P LS is not an independent predictor of post-STEMI HF development and mechanical dyssynchrony does not provide independent prognostic information regarding HF when GLS is known.

Presence of post-systolic shortening is an independent predictor of heart failure in patients following ST-segment elevation myocardial infarction

Following an ischemic event post systolic shortening (PSS) may occur. We investigated the association between PSS in patients with ST-segment elevation myocardial infarction (STEMI) following primary percutaneous coronary intervention (pPCI) and occurrence of cardiovascular events at follow-up. A total of 373 patients admitted with STEMI and treated with pPCI were prospectively included in the study cohort. All patients were examined by echocardiography a median of 2 days after admission (interquartile range, 1-3 days). PSS was measured by color tissue Doppler imaging (TDI) and speckle tracking echocardiography (STE) in six myocardial walls from all three apical projections. During a median follow-up period of 5.4 years (interquartile range, 4.1-6.0 years), 180 events occurred: 59 deaths, 70 heart failures (HF) and 51 new myocardial infarctions (MI). In multivariable analysis adjusting for: age, sex, peak troponin, left ventricle ejection fraction, TIMI flow grade, left ventricle mass index, hypertension and diabetes, presence of PSS by TDI in the culprit region was associated with a nearly twofold increased risk of HF (HR 1.90, 95% CI 1.02-3.53, P = 0.043) and the risk of HF increased incrementally with increasing numbers of walls displaying PSS. The increased risk of HF was confirmed when assessing the post-systolic index by STE (HR 1.29 95% CI 1.09-1.53, P = 0.003, per 1% increase). A regional analysis showed that PSS by TDI in the septal wall was the strongest predictor of HF (HR 1.77, 95% CI 1.08-2.92, P = 0.024). Presence of PSS was not associated with increased risk of death or MI. In patients with STEMI treated with pPCI, the presence of PSS examined by TDI and STE provides prognostic information on development of HF. Presence of PSS in the septal wall is the strongest predictor of HF.

Left ventricular ejection time is an independent predictor of incident heart failure in a community-based cohort

AIMS

Systolic time intervals change in the progress of cardiac dysfunction. The usefulness of left ventricular ejection time (LVET) to predict cardiovascular morbidity, however, is unknown.

METHODS AND RESULTS

We studied middle-aged African-Americans from one of four cohorts of the Atherosclerosis Risk in Communities study (Jackson cohort, n=1980) who underwent echocardiography between 1993 and 1995. Left ventricular ejection time was measured by pulsed-wave Doppler of the left ventricular outflow tract and related to outcomes. A shorter LVET was associated with younger age, male sex, higher diastolic blood pressure, higher proportion of diabetes, higher heart rate, higher blood glucose levels and worse fractional shortening. During a median follow-up of 17.6 years, 384 (19%) had incident heart failure (HF), 158 (8%) had a myocardial infarction, and 587 (30%) died. In univariable analysis, a lower LVET was significantly associated with increased risk of all events (P<0.05 for all). However, after multivariable adjustment for age, sex, hypertension, diabetes, body mass index, heart rate, systolic and diastolic blood pressure, fractional shortening and left atrial diameter, LVET remained an independent predictor only of incident HF [hazard ratio 1.07 (1.02-1.14), P=0.010 per 10 ms decrease]. In addition, LVET provided incremental prognostic information to the known risk factors included in the Framingham risk score, in regard to predicting all outcomes except for myocardial infarction.

CONCLUSION

Left ventricular ejection time is an independent predictor of incident HF in a community-based cohort and provides incremental prognostic information on the risk of future HF and death when added to known risk prediction models.

Global Longitudinal Strain by Echocardiography Predicts Long-Term Risk of Cardiovascular Morbidity and Mortality in a Low-Risk General Population: The Copenhagen City Heart Study

BACKGROUND

Global longitudinal strain (GLS) is prognostic of adverse cardiovascular outcomes in various patient populations, but the prognostic utility of GLS for long-term cardiovascular morbidity and mortality in the general population is unknown.

METHODS AND RESULTS

A total of 1296 participants in a general population study underwent a health examination, including echocardiography measurement of GLS. The primary end point was the composite of incident heart failure, acute myocardial infarction, or cardiovascular death. During a median follow-up of 11 years, 149 (12%) participants were diagnosed with heart failure, acute myocardial infarction, or cardiovascular death. Lower GLS was associated with a higher risk of the composite end point (hazard ratio, 1.12; 95% confidence interval, 1.08-1.17; P<0.001 per 1% decrease), an association that persisted after multivariable adjustment for age, sex, heart rate, hypertension, systolic blood pressure, left ventricular ejection fraction, left ventricular mass index, left ventricular dimension, deceleration time, left atrium dimension, E/e', and pro B-type natriuretic peptide (hazard ratio, 1.05; 95% confidence interval, 1.00-1.11; P=0.045 per 1% decrease). GLS provided incremental prognostic information beyond the Framingham Risk Score, the Systemic Coronary Evaluation risk chart, and the modified American College of Cardiology/American Heart Association Pooled Cohort Equation for the composite outcome and incident heart failure. Sex modified the relationship between GLS and outcome such that after multivariable adjustment, GLS was an independent predictor of outcomes in men but not in women (hazard ratio, 1.14; 95% confidence interval, 1.06-1.24; P=0.001, and hazard ratio, 0.99; 95% confidence interval, 0.92-1.07; P=0.81, respectively; P for interaction =0.032).

CONCLUSIONS

In the general population, GLS provides independent and incremental prognostic information regarding long-term risk of cardiovascular morbidity and mortality. GLS seems to be a stronger prognosticator in men than in women.

Global longitudinal strain predicts incident atrial fibrillation and stroke occurrence after acute myocardial infarction

Patients with acute myocardial infarction are at increased risk of developing atrial fibrillation. We aimed to evaluate whether speckle tracking echocardiography improves risk stratification for atrial fibrillation in these patients.The study comprised of 373 patients with ST-segment elevation myocardial infarction (STEMI) treated with primary percutaneous coronary intervention. Patients had an echocardiogram performed at a median of 2 days after their STEMI. The echocardiograms consisted of conventional measurements and myocardial strain analysis by speckle tracking from 3 apical projections. The endpoint was a composite of new-onset atrial fibrillation and ischemic stroke. At a median follow-up time of 5.5 years (interquartile range 4.9, 6.1 years), 44 patients developed the endpoint (atrial fibrillation: n = 24, ischemic stroke: n = 24, both: n = 4). Patients who reached the endpoint had significantly reduced systolic function by the left ventricular ejection fraction (LVEF) (43% vs 46%; P = 0.042) and global longitudinal strain (10.9% vs 12.6%; P = 0.004), both being univariable predictors. However, only global longitudinal strain remained a significantly independent predictor (hazard ratio 1.12, 95% confidence interval 1.00; 1.25, P = 0.042, per 1% decrease) after multivariable adjustment for baseline predictors (age, sex, diabetes, hypertension, diastolic dysfunction, and LVEF) using Cox regression. Furthermore, global longitudinal strain resulted in significantly higher c-statistics for prediction of outcome compared with LVEF <45% (0.63 vs 0.52; P = 0.026). When stratified into tertiles of global longitudinal strain, it became evident that patients in the lowest tertile mediated this signal with a 2-fold increased risk compared with the highest tertile (hazard ratio 2.10, 95% confidence interval 1.04; 4.25).Global longitudinal strain predicts atrial fibrillation after STEMI and may add valuable information which can help facilitate arrhythmia detection in these patients.

Regional Longitudinal Myocardial Deformation Provides Incremental Prognostic Information in Patients with ST-Segment Elevation Myocardial Infarction

Background

Global longitudinal systolic strain (GLS) has recently been demonstrated to be a superior prognosticator to conventional echocardiographic measures in patients after myocardial infarction (MI). The aim of this study was to evaluate the prognostic value of regional longitudinal myocardial deformation in comparison to GLS, conventional echocardiography and clinical information.

Method

In total 391 patients were admitted with ST-Segment elevation myocardial infarction (STEMI), treated with primary percutaneous coronary intervention and subsequently examined by echocardiography. All patients were examined by tissue Doppler imaging (TDI) and two-dimensional strain echocardiography (2DSE).

Results

During a median-follow-up of 5.3 (IQR 2.5–6.1) years the primary endpoint (death, heart failure or a new MI) was reached by 145 (38.9%) patients. After adjustment for significant confounders (including conventional echocardiographic parameters) and culprit lesion, reduced longitudinal performance in the anterior septal and inferior myocardial regions (but not GLS) remained independent predictors of the combined outcome. Furthermore, inferior myocardial longitudinal deformation provided incremental prognostic information to clinical and conventional echocardiographic information (Harrell's c-statistics: 0.63 vs. 0.67, p = 0.032). In addition, impaired longitudinal deformation outside the culprit lesion perfusion region was significantly associated with an adverse outcome (p<0.05 for all deformation parameters).

Conclusion

Regional longitudinal myocardial deformation measures, regardless if determined by TDI or 2DSE, are superior prognosticators to GLS. In addition, impaired longitudinal deformation in the inferior myocardial segment provides prognostic information over and above clinical and conventional echocardiographic risk factors. Furthermore, impaired longitudinal deformation outside the culprit lesion perfusion region seems to be a paramount marker of adverse outcome.

Cardiac Time Intervals by Tissue Doppler Imaging M-Mode: Normal Values and Association with Established Echocardiographic and Invasive Measures of Systolic and Diastolic Function

PURPOSE

To define normal values of the cardiac time intervals obtained by tissue Doppler imaging (TDI) M-mode through the mitral valve (MV). Furthermore, to evaluate the association of the myocardial performance index (MPI) obtained by TDI M-mode (MPITDI) and the conventional method of obtaining MPI (MPIConv), with established echocardiographic and invasive measures of systolic and diastolic function.

METHODS

In a large community based population study (n = 974), where all are free of any cardiovascular disease and cardiovascular risk factors, cardiac time intervals, including isovolumic relaxation time (IVRT), isovolumic contraction time (IVCT), and ejection time (ET) were obtained by TDI M-mode through the MV. IVCT/ET, IVRT/ET and the MPI ((IVRT+IVCT)/ET) were calculated. We also included a validation population (n = 44) of patients who underwent left heart catheterization and had the MPITDI and MPIConv measured.

RESULTS

IVRT, IVRT/ET and MPI all increased significantly with increasing age in both genders (p<0.001 for all). IVCT, ET, IVRT/ET, and MPI differed significantly between males and females, displaying that women, in general exhibit better cardiac function. MPITDI was significantly associated with invasive (dP/dt max) and echocardiographic measures of systolic (LVEF, global longitudinal strain and global strainrate s) and diastolic function (e', global strainrate e)(p<0.05 for all), whereas MPIConv was significantly associated with LVEF, e' and global strainrate e (p<0.05 for all).

CONCLUSION

Normal values of cardiac time intervals differed between genders and deteriorated with increasing age. The MPITDI (but not MPIConv) is associated with most invasive and established echocardiographic measures of systolic and diastolic function.

Cardiac Time Intervals Measured by Tissue Doppler Imaging M-mode: Association With Hypertension, Left Ventricular Geometry, and Future Ischemic Cardiovascular Diseases

BACKGROUND

We hypothesized that the cardiac time intervals reveal reduced myocardial function in persons with hypertension and are strong predictors of future ischemic cardiovascular diseases in the general population.

METHODS AND RESULTS

In a large community-based population study, cardiac function was evaluated in 1915 participants by using both conventional echocardiography and tissue Doppler imaging (TDI). The cardiac time intervals, including the isovolumic relaxation time (IVRT), isovolumic contraction time (IVCT), and ejection time (ET), were obtained by TDI M-mode through the mitral leaflet. IVCT/ET, IVRT/ET, and myocardial performance index [MPI=(IVRT+IVCT)/ET] were calculated. After multivariable adjustment for clinical variables the IVRT, IVRT/ET, and MPI, remained significantly impaired in persons with hypertension (n=826) compared with participants without hypertension (n=1082). Additionally, they displayed a significant dose-response relationship, between increasing severity of elevated blood pressure and increasing left ventricular mass index (P<0.001 for all). Further, during follow-up of a median of 10.7 years, 435 had an ischemic cardiovascular disease (ischemic heart disease, peripheral arterial disease, or stroke). The IVRT/ET and MPI were powerful and independent predictors of future cardiovascular disease, especially in participants with known hypertension. They provide prognostic information incremental to clinical variables from the Framingham Risk Score, the SCORE risk chart, and the European Society of Hypertension/European Society of Cardiology risk chart.

CONCLUSION

The cardiac time intervals identify impaired cardiac function in individuals with hypertension, not only independent of conventional risk factors but also in participants with a normal conventional echocardiographic examination. The IVRT/ET and MPI are independent predictors of future cardiovascular disease especially in participants with known hypertension.

Prognostic value of cardiac time intervals measured by tissue Doppler imaging M-mode in the general population

OBJECTIVE

Tissue Doppler imaging (TDI) M-mode through the mitral leaflet is an easy and precise method to estimate the cardiac time intervals. The aim was to evaluate the usability of the cardiac time intervals in predicting major cardiovascular events (MACE) in the general population.

METHODS

In a large prospective community-based study, cardiac function was evaluated in 1915 participants by both conventional echocardiography and TDI. The cardiac time intervals, including the isovolumic relaxation time (IVRT), isovolumic contraction time (IVCT) and ejection time (ET), were obtained by TDI M-mode through the mitral leaflet. IVCT/ET, IVRT/ET and the myocardial performance index (MPI=(IVRT+IVCT)/ET) were calculated.

RESULTS

During follow-up (median 10.8 years), 383 (20%) participants reached the combined endpoint MACE (ischaemic heart disease, heart failure or cardiac death). After multivariable adjustment for clinical predictors and conventional echocardiography, only the combined indexes, including information on both systolic and diastolic performance (IVRT/ET and MPI), remained significant prognosticators (p<0.05 for both). Adding IVRT/ET or MPI to a model already including all other echocardiographic parameters resulted in a significant increase in the c-statistics (0.76 vs 0.75 p<0.01 for both). IVRT/ET or MPI improved reclassification significantly when added to the clinical predictors (p<0.05 for both).

CONCLUSIONS

In the general population, the combined cardiac time intervals that include information on both systolic and diastolic function in one index (IVRT/ET and MPI) are not only powerful and independent predictors of future MACE, but provide additional prognostic information to clinical and conventional echocardiographic measures of systolic and diastolic function.

The prognostic value of mechanical left ventricular dyssynchrony in patients with acute coronary syndrome

Background

Echocardiography is a well-established tool for risk stratification in patients with acute coronary syndrome (ACS). ACS has significant impact on LV dyssynchrony, and detrimental effects on systolic function and long term outcome. The aims of this study were to determine whether LV dyssynchrony carries any predictive information in an unselected ACS population and to evaluate if it has any incremental value to the information given from conventional echocardiographic measurements.

Methods

The study included 227 consecutive ACS patients. Primary endpoint was the composite of death, new MI, or rehospitalisation due to heart failure. Dyssynchrony was measured as intersegmental variation of time to peak strain, the post systolic index (PSI) and myocardial performance index (MPI) with the standard deviation and difference between lowest and highest value (delta) expressing the amount of dyssynchrony. Septal-lateral delay was also tested. All dyssynchrony parameters were compared with Ejection fraction (EF).

Results

The median follow up time was 53 months. 85 patients reached the combined endpoint. Patients with and without a subsequent combined endpoint differed significantly regarding calculated SD: s and delta-value for PSI, time to peak 2D-strain and MPI but not regarding septal-lateral delay. In ROC-analysis none of the dyssynchrony parameters had larger AUC than EF. When adjusting for traditional risk factors none of the dyssynchrony parameters remained associated with outcome, whereas EF still did.

Conclusion

LV dyssynchrony seem to have significant prognostic information in patient with acute coronary syndrome but in comparison to conventional parameters such as EF there is no incremental value of this information.