Association Between Segmental Noninvasive Myocardial Work and Microvascular Perfusion in ST-Segment Elevation Myocardial Infarction: Implications for Left Ventricular Functional Recovery and Clinical Outcomes.

BACKGROUND: Predicting left ventricular recovery (LVR) after acute ST-segment elevation myocardial infarction (STEMI) is of prognostic importance. This study aims to explore the prognostic implications of segmental noninvasive myocardial work (MW) and microvascular perfusion (MVP) after STEMI. METHODS: In this retrospective study, 112 patients with STEMI who underwent primary percutaneous coronary intervention and transthoracic echocardiography after percutaneous coronary intervention were enrolled. Microvascular perfusion was analyzed by myocardial contrast echocardiography, and segmental MW was analyzed by noninvasive pressure-strain loops. A total of 671 segments with abnormal function at baseline were analyzed. The degrees of MVP were observed following intermittent high-mechanical index impulses: replenishment within 4 seconds (normal MVP), replenishment >4 seconds and within 10 seconds (delayed MVP), and persistent defect (microvascular obstruction). The correlation between MW and MVP was analyzed. The correlation of the MW and MVP with LVR (normalization of wall thickening, >25%) was assessed. The prognostic value of segmental MW and MVP for cardiac events (cardiac death, admission for congestive heart failure, or recurrent myocardial infarction) was evaluated. RESULTS: Normal MVP was seen in 70 segments, delayed MVP in 236, and microvascular obstruction in 365. The segmental MW indices were independently correlated with MVP; 244 (36.4%) segments had segmental LVR at 3-month follow-up. Segmental MW efficiency and MVP were independently associated with segmental LVR (P < .05). The χ2 of combination of segmental MW efficiency and MVP was higher than either index alone for identifying segmental LVR (P < .001). At a median follow-up of 42.0 months, cardiac events occurred in 13 patients; all regional MW parameters, high sensitivity troponin I, regional longitudinal strain, and so on were associated with cardiac events. CONCLUSIONS: Segmental MW indices are associated with MVP within the infarct zone following reperfused STEMI. Both are independently associated with segmental LVR, and regional MW is associated with cardiac events, providing prognostic value in STEMI patients.

Evaluation of left atrial function and mechanical dispersion in breast cancer patients after chemotherapy.

BACKGROUND: Left atrial (LA) function and mechanical dispersion changes in breast cancer patients treated with chemotherapy remain unclear. HYPOTHESIS: LA function and LA mechanical dispersion in breast cancer patients would be impaired after chemotherapy. METHODS: This single-center retrospective study included 91 consecutive breast cancer patients treated with chemotherapy and 30 controls. Patients were examined by echocardiography three times at intervals. Conventional parameters, left ventricular strain, LA strain, and LA mechanical dispersion were evaluated and compared. RESULTS: LA strain during reservoir phase (LASr), conduit phase (LAScd), and contraction phase (LASct) all decreased markedly after chemotherapy and were lower than those of the controls (all p < .01). The standard deviation of time to peak positive strain during LA reservoir phase corrected by R-R interval (LA SD-TPSr) was significantly increased after chemotherapy and was higher than that of the controls (p < .001). The change of LA function was expressed as Δ. Multivariate linear regression analyses showed that LAVIp (0.399, 95% confidence interval [CI]: 0.610, 1.756, p = .000) was independently associated with ΔLASr, LAPEF (-0.325, 95% CI: -45.123, -10.676, p = .002) and age (0.227, 95% CI: 0.021, 0.350, p = .027) were independently associated with ΔLAScd, and LAVImax (0.341, 95% CI: 0.192, 0.723, p = .001) was independently associated with ΔLASct. LAVImax (0.505, 95% CI: 0.000, 0.001, p = .039) and mitral E (-0.256, 95% CI: 0.000, 0.000, p = .024）were independently associated with ΔLA SD-TPSr. CONCLUSIONS: Mechanical function of LA declined after chemotherapy in breast cancer patients. With the decrease of LA mechanical function, LA mechanical dispersion assessed by two-dimensional speckle-tracking echocardiography increased significantly, and its clinical value needs to be further studied.

Quantitative analysis of mitral valve morphology in atrial functional mitral regurgitation using real-time 3-dimensional echocardiography atrial functional mitral regurgitation.

BACKGROUND: Atrial fibrillation (AF) can result in atrial functional mitral regurgitation (MR), but the mechanism remains controversial. Few data about the relationship between the 3-dimensional morphology of the MV and the degree of MR in AF exist. METHODS: Real-time 3-dimensional transesophageal echocardiography (3D-TEE) of the MV was acquired in 168 patients with AF (57.7% persistent AF), including 25 (14.9%) patients with moderate to severe MR (the MR+ group) and 25 patients without AF as controls. The 3-dimensional geometry of the MV apparatus was acquired using dedicated quantification software. RESULTS: Compared with the group of patients with no or mild MR (the MR- group) and the controls, the MR+ group had a larger left atrium (LA), a more dilated mitral annulus (MA), a reduced annular height to commissural width ratio (AHCWR), indicating flattening of the annular saddle shape, and greater leaflet surfaces and tethering. MR severity was correlated with the MA area (r2 = 0.43, P < 0.01) and the annulus circumference (r2 = 0.38, P < 0.01). A logistic regression analysis indicated that the MA area (OR: 1.02, 95% CI: 1.01-1.03, P < 0.01), AHCWR (OR: 0.24, 95% CI: 0.14-0.35, P = 0.04) and MV tenting volume (OR: 3.24, 95% CI: 1.16-9.08, P = 0.03) were independent predictors of MR severity in AF patients. CONCLUSIONS: The mechanisms of "atrial functional MR" are complex and include dilation of the MA, flattening of the annular saddle shape and greater leaflet tethering.

Assessment of left atrial mechanical function and synchrony in paroxysmal atrial fibrillation with two-dimensional speckle tracking echocardiography.

BACKGROUND: The aim of this study was to investigate left atrial (LA) function and synchrony in paroxysmal atrial fibrillation (PAF) patients using two-dimensional speckle tracking echocardiography (STE). METHODS: Forty-five PAF patients and 30 healthy controls were enrolled. LA peak ventricular systolic longitudinal strain (LAS-S ) and strain rate (LASR-S ) and left atrial longitudinal strain (LAS-A ) and strain rate (LASR-A ) during late diastole were determined using STE, and the standard deviation of the time to peak (TPSD) of the regional strains was calculated to quantify LA dyssynchrony. TPSD during ventricular systole and late diastole were named SDs and SDa, respectively. RESULTS: Left atrial peak longitudinal strain during ventricular systole (LAS-S ) (29.34±8.57 vs 36.73±6.13), LASR-S (1.27±0.311 vs 1.57±0.25), LAS-A (13.11±4.91 vs 17.86±3.57), and LASR-A (-1.51±0.58 vs -1.90±0.30) were reduced in the PAF group compared with the controls (P<.05 for all). SDs (8.11±3.00% vs 4.67±1.48%) and SDa (5.57±2.26% vs 3.11±1.13%) were greater in PAF patients than in the controls (P<.05 for both). Furthermore, PAF patients with normal LA sizes exhibited lower LAS-S (P<.05), LASR-S (P<.05), LAS-A (P<.05), and LASR-A (P<.05) values and increased SDs (P<.05) and SDa (P<.05) values compared with the controls. Multivariate regression confirmed that SDs and SDa were powerful parameters for differentiating PAF patients from controls (SDs: sensitivity, 83%; specificity, 72%; SDa: sensitivity, 81%; specificity, 76%). CONCLUSIONS: Left atrial (LA) dysfunction and dyssynchrony in PAF patients can be detected with STE even in the absence of LA enlargement. STE-derived SDs and SDa were powerful parameters for identifying PAF patients.

Different Combinations of Right Ventricular Longitudinal Velocity and Displacement Can Be Applied Effectively for Diagnosis of Right Heart Failure in Chinese Patients.

BACKGROUND: The noninvasive evaluation of right ventricular function (RVF) in cardiovascular and pulmonary diseases remains a challenge. Internationally recommended echocardiographic parameters for the evaluation of RVF may not be applicable to China, because of the limited examination time per patient, the varying skill levels of ultrasonographers, inadequate allocation of professional specialties, and outdated instruments and equipment. METHODS: Sixty-two patients admitted for right heart failure and 52 healthy volunteers were included in the analysis. The tricuspid annular plane systolic excursion (TAPSE), peak systolic velocity in the tricuspid annulus of the right ventricular free wall (S'), myocardial performance index, right ventricular fractional area change, and Doppler peak strains in the base and mid cavity were evaluated and compared between groups. RESULTS: Compared with the control group, all RVF parameters in the right heart failure group showed significant deterioration (P < .001). However, only TAPSE and S' were finally included in the discriminant equation. The diagnostic cutoff values derived from the receiver operating characteristic curve were <13.74 mm and <9.5 cm/s, respectively. The highest specificity in the diagnosis of right heart failure (100%) was achieved using S' <9.5 cm/s, either alone or in combination with TAPSE <13.74 mm. The highest diagnostic sensitivity (90.32%) was achieved using either TAPSE <13.74 mm or S' <9.5 cm/s alone. CONCLUSION: TAPSE and S' are more suitable than other parameters for the diagnosis of right heart failure in Chinese patients. Different combinations of TAPSE and S' can be applied effectively for the diagnosis of right heart failure.

Prognostic Value of Speckle Tracking Echocardiography in Patients with ST-Elevation Myocardial Infarction Treated with Late Percutaneous Intervention.

BACKGROUND: Left ventricular remodeling (LVr) is common after ST-segment elevation myocardial infarction (STEMI). The aim of this study was to evaluate the prognostic value of speckle tracking echocardiography (STE) for predicting LVr 6-9 months after late percutaneous coronary intervention (PCI) in patients with STEMI. METHODS: Patients with first STEMI who accepted late PCI were enrolled. Echocardiography was performed within 48 hours of admission. Six to nine months after MI, an echocardiography examination was repeated. LVr was defined as >15% increase in LV end-systolic volume (LVESV) after 6 months. RESULTS: One hundred and twenty-seven patients were divided into two groups: 86 patients without LVr and 41 patients with LVr. There were significant differences in the global longitudinal strain (GLS), SD of time to peak longitudinal systolic strain (longitudinal Ts-SD), longitudinal postsystolic index, radial strain (RS), and SD of time to peak radial systolic strain (Radial Ts-SD). In multivariate logistic regression analysis, the GLS(odds ratio [OR] = 0.39, 95% confidence interval [CI] = 0.26-0.57, P < 0.01), and RS(OR = 1.07, 95% CI = 1.02-1.13, P = 0.01) were determinants of LVr. A receiver operating characteristic curve showed that the GLS predicted LVr with an optimal cutoff value of -10.85 (sensitivity: 89.7%, specificity: 91.7%). During clinical follow-up for 16.9 ± 1.6 months, death or congestive heart failure developed in 12 patients (9.4%), and the baseline ejection fraction (OR = 1.91, 95% CI = 1.18-3.1, P = 0.009) and GLS (OR = 0.56, 95% CI = 0.34-0.91, P = 0.02) were independent predictors. CONCLUSION: In patients with STEMI treated with late percutaneous coronary intervention, the GLS as measured by STE is a strong predictor of LVr and adverse events.

Myocardial dysfunction in early diabetes patients with microalbuminuria: a 2-dimensional speckle tracking strain study.

The aim of this study was to assess myocardial dysfunction in primary diabetes patients with microalbuminuria by 2-dimensional speckle tracking strain. Sixty-two patients with diabetes with or without hypertension and 37 matched hypertension controls were consecutively recruited from January 2011 to 2013. Routine physical examinations, laboratory tests, and echocardiography were performed in all patients. Subjects enrolled were divided into three groups according to history and urine albumin/creatinine ratio (ACR): group I: patients with only hypertension and normoalbuminuria (ACR < 30 mg/g), group II: patients with both hypertension and diabetes and normoalbuminuria (ACR < 30 mg/g), and group III: patients with both hypertension and diabetes and microalbuminuria (ACR 30-300 mg/g). Echocardiographic images of three cardiac cycles were acquired for off-line analysis using the GE EchoPAC software. Indices of cardiac function, including longitudinal, radial and circumferential strains, torsion, and left ventricular ejection fraction (LVEF) were assessed. Statistical analysis was performed using SPSS 13.0. Finally, 56 subjects and 32 controls were included in the analyses. There was no significant difference in age, gender, heart rate, BMI, and LVEF among groups, except for the blood pressure, ACR, and HbA1c. E wave, A wave, EDT, E m, and E/E m in group III were different with those in group I. Mean longitudinal strain (mSL), average SL of six segments in 4-chamber apical view (SL4) decreased obviously. The peak circumferential strain decreased in group III, while the torsion was compensatively increased. ACR was negatively related to mSL, SL4, E/E m, and positively related to torsion. We deduced that ACR maybe a predictor for myocardial damage in primary diabetes.

Noninvasive assessment of left atrial phasic function in patients with hypertension and diabetes using two-dimensional speckle tracking and volumetric parameters.

OBJECTIVE: To evaluate the left atrial phasic function of hypertensive patients with or without coexisting diabetes using two-dimensional speckle tracking echocardiography (2DSTE)-based strain and strain rate imaging and volumetric parameters. METHODS: The study included an isolated hypertension group (HT group) comprising 99 patients, a hypertension and diabetes group (HT + DM group) comprising 65 patients, and 26 age-matched healthy controls. The 2DSTE-based strain and strain rate images were studied, and the following parameters were measured: peak left atrial longitudinal strain (LAS-S ), early diastolic (LAS-E ) and late diastolic (LAS-A ) atrial longitudinal strains, and systolic (LASR-S ), early diastolic (LASR-E ) and late diastolic (LASR-A ) strain rates. RESULTS: The LAS-S and LASR-S were lower in the HT group and the HT + DM group compared with the control group (P < 0.001). The LAS-E and LASR-E were lower in the HT group (14.9 ± 5.5% and -1.1 ± 0.4/sec, respectively) than in the control group (22.1 ± 8.3% and -1.7 ± 0.6/sec, respectively) (P < 0.001), and they were further depressed in the HT + DM group (12.3 ± 6.3% and -1.0 ± 0.4/sec, respectively) (P < 0.05). There were no significant differences in LAS-A or LASR-A among the 3 groups (P > 0.05). Multivariate regression analysis revealed that HT and DM were independently related to LAS-E and LASR-E . CONCLUSIONS: Hypertension can lead to abnormal left atrial reservoir and conduit functions, and coexisting diabetes can further impair conduit function. 2DSTE-derived strain and strain rate imaging are sensitive methods for evaluating left atrial phasic function.