Impaired coronary flow reserve as a marker of microvascular dysfunction to predict long-term cardiovascular outcomes, acute coronary syndrome and the development of heart failure.

BACKGROUND: In the absence of obstructive coronary narrowing, impaired coronary flow reserve (CFR) represents coronary microvascular dysfunction. Transthoracic Doppler echocardiography (TTDE) allows non-invasive measurement of CFR in the left anterior descending (LAD) artery. This study aimed to assess the prognostic value of TTDE-derived CFR (as a marker of microvascular function) in predicting long-term cardiovascular events, acute coronary syndrome (ACS) events, and the development of heart failure (HF). METHODS AND RESULTS: This study consisted of 272 patients with coronary artery disease not involving obstructive narrowing (≥50%) in the LAD. Patients underwent TTDE examination for CFR measurement in the LAD. During the follow-up period of 4.0±1.9 years, 32 patients (12%) had cardiovascular events. Cox proportional hazard analysis identified lower CFR as an independent risk factor of cardiovascular events (P<0.001), ACS events (P=0.008), and HF development (P=0.003). A CFR less than 2.4 was the best cut-off value for predicting all events (area under the curve=0.82). CFR excellently predicted the development of HF (area under the curve=0.95), but not ACS events (area under the curve=0.67). CONCLUSIONS: This TTDE study demonstrated that CFR was a significant and independent determinant of long-term cardiovascular events, ACS events and HF in patients with coronary artery disease. A CFR greater than 2.0 was not suitable to predict a favorable long-term outcome, even in the absence of obstructive coronary narrowing.

Miction-induced Hypertension Disclosed by Home Blood Pressure Measurement in a Patient with Small Paraganglioma.

A 46-year-old woman complained of a 10-year history of headache, nausea, a precordial oppressive feeling and shortness of breath on miction. She had noted a marked elevation in her blood pressure after miction using home blood pressure measurement. Her catecholamine levels were less than twice the value of the normal upper limit. Several imaging modalities detected a urinary bladder tumor, and 123I-metaiodobenzylguanidine scintigraphy showed positive accumulation. The diagnosis of urinary bladder paraganglioma was confirmed by partial cystectomy. We must keep in mind that paroxysms and hypertension associated with miction are important diagnostic clues of pheochromocytoma/paraganglioma. Home blood pressure measurement was very useful for detecting hypertension in this case.

Comparison of echocardiographic dyssynchrony assessment by tissue velocity and strain imaging in subjects with or without systolic dysfunction and with or without left bundle-branch block.

BACKGROUND: Several echocardiographic dyssynchrony indexes have been proposed to identify responders to cardiac resynchronization therapy using tissue velocity and strain. The present study aimed to compare tissue velocity-derived and strain-derived dyssynchrony indexes in patients with or without systolic dysfunction and left bundle-branch block. METHODS AND RESULTS: Tissue Doppler imaging was performed in 120 subjects divided into 4 groups: group 1 (n=40), normal subjects; group 2 (n=20), normal left ventricular ejection fraction and left bundle-branch block; group 3 (n=20), left ventricular ejection fraction <35% and normal conduction; and group 4 (n=40), left ventricular ejection fraction <35% and left bundle-branch block. Dyssynchrony indexes based on time to peak tissue velocity (septal-lateral delay, anteroseptal-posterior delay, and SD in time to peak systolic velocity in the 12 left ventricular segments) and strain (SD of time to peak strain in 12 segments) were measured. The SD in time to peak systolic velocity in the 12 left ventricular segments was greater in group 4 (54 ms; 25th and 75th percentiles, 46 to 64 ms) than group 1 (44 ms; 25th and 75th percentiles, 28 to 53 ms; P=0.006), but there was a considerable overlap of all tissue velocity-derived indexes among 4 groups, with 40% to 68% of group 1 having values proposed for predicting the responders of cardiac resynchronization therapy. The SD of time to peak strain in 12 segments distinguished these groups with much less overlap (P<0.01 for all pairwise comparisons). CONCLUSIONS: A substantial proportion of normal subjects have tissue velocity-derived dyssynchrony indexes higher than the cutoff value proposed for predicting beneficial effect of cardiac resynchronization therapy. Strain-derived timing index appears to be more specific for dyssynchrony in patients with systolic dysfunction and left bundle-branch block. Identifying an optimal tissue velocity- or strain-derived dyssynchrony index requires a large prospective clinical trial.

Prognostic significance of residual functional mitral regurgitation in hospitalized heart failure patients with chronic atrial fibrillation and preserved ejection fraction after medical therapies.

BACKGROUND: Functional mitral regurgitation (MR) can be seen in patients with atrial fibrillation (AF), even without left-ventricular (LV) systolic dysfunction, as a result of left atrial enlargement. The purpose of this study was to evaluate the prognostic significance of residual functional MR in hospitalized heart failure patients with chronic AF and preserved LV ejection fraction (pEF) after medical therapies. METHODS: In this retrospective multi-center study, the determinants of post-discharge prognosis (cardiac death and re-hospitalization for worsening heart failure) were examined in 54 hospitalized heart failure patients with chronic AF and pEF at discharge. RESULTS: Of the 54 patients, 53 (98%) had mild or higher degrees of functional MR at hospitalization.At discharge, 47 (87%) still had functional MR, even after medical therapies [mild in 27 (50%), moderate in 16 (30%), and severe in 4 (7%)]. During the follow-up period (20 ± 16 months) after discharge, 16 (30%) patients met the composite end points. The grading of residual functional MR at discharge was the significant predictor of the end point (hazard ratio per one grade increase: 2.4, 95% confidence interval 1.1-5.5, p = 0.035). The greater the residual functional MR was, the lower the event-free rate from the end point was in the Kaplan-Meier curve analysis (p = 0.0069 for trend). CONCLUSIONS: A substantial proportion of patients hospitalized due to heart failure with chronic AF have residual functional MR at discharge, even with pEF after medical therapies, and the MR is related to future heart failure events.

Evidence of impaired left ventricular systolic function by Doppler myocardial imaging in patients with systemic amyloidosis and no evidence of cardiac involvement by standard two-dimensional and Doppler echocardiography.

We examined the potential role of Doppler myocardial imaging for early detection of systolic dysfunction in patients with systemic amyloidosis (AL) but without evidence of cardiac involvement by standard echocardiography. We identified 42 patients without 2-dimensional echocardiographic or Doppler evidence of cardiac involvement. These patients had normal ventricular wall thickness and normal velocity of the medial mitral annulus. Myocardial images were obtained in these patients and in 32 age- and gender-matched healthy controls. Peak longitudinal systolic tissue velocity (sTVI), systolic strain rate (sSR), and systolic strain (sS) were determined for 16 left ventricular segments. Radial and circumferential sSR and sS were also measured. Compared with controls in this group of patients with AL, peak longitudinal sSR (-1.0 +/- 0.2 vs -1.4 +/- 0.2, p <0.001) and peak longitudinal sS (-15.6 +/- 3.3 vs -22.5 +/- 2.0 p <0.001) were significantly decreased. In conclusion, the mean sS from all 6 basal segments, or from all 16 left ventricular segments differentiated patients with AL with normal echocardiography from controls, with similar accuracy for the mean sSR from the 6 basal segments. This distinction was not apparent from peak longitudinal sTVI or from radial or circumferential sSI or sSR.

Cardiac resynchronization therapy upregulates cardiac autonomic control.

OBJECTIVE: To determine the effect of cardiac resynchronization therapy (CRT) on sympathetic nervous function in heart failure (HF). BACKGROUND: Neurohormonal dysregulation and cardiac autonomic dysfunction are associated with HF and contribute to HF progression and its poor prognosis. We hypothesized that mechanical resynchronization improves cardiac sympathetic function in HF. METHODS: Sixteen consecutive patients receiving CRT for advanced cardiomyopathy and 10 controls were included in this prospective study. NYHA class, 6-minute walk distance, echocardiographic parameters, plasma norepinephrine (NE) were assessed at baseline, 3-month and 6-month follow-up. Cardiac sympathetic function was determined by (123)iodine metaiodobenzylguanidine ((123)I-MIBG) scintigraphy and 24-hour ambulatory electrocardiography. RESULTS: Along with improvement in NYHA class (3.1 +/- 0.3 to 2.1 +/- 0.4, P < 0.001) and LVEF (23 +/- 6% to 33 +/- 12%, P < 0.001), delayed heart/mediastinum (H/M) (123)I-MIBG ratio increased significantly (1.8 +/- 0.7 to 2.1 +/- 0.6, P = 0.04) while the H/M (123)I-MIBG washout rate decreased significantly (54 +/- 25% to 34 +/- 24%, P = 0.01) from baseline to 6-month follow-up. The heart rate variability (HRV) measured in SD of normal-to-normal intervals also increased significantly from baseline (82 +/- 30 ms) to follow-up (111 +/- 32 ms, P = 0.04). The improvement in NYHA after CRT was significantly associated with baseline (123)I-MIBG H/M washout rate (r = 0.65, P = 0.03). The improvement in LVESV index was associated with baseline (123)I-MIBG delayed H/M ratio (r =-0.67, P = 0.02) and H/M washout rate (r = 0.65, P = 0.03). CONCLUSION: After CRT, improvements in cardiac symptoms and LV function were accompanied by rebalanced cardiac autonomic control as measured by (123)I-MIBG and HRV.

Enhanced coronary flow velocity during intra-aortic balloon pumping assessed by transthoracic Doppler echocardiography.

OBJECTIVES: The study was done to determine potential utility of measuring coronary flow velocity (CFV) by transthoracic Doppler echocardiography (TTDE) during intra-aortic balloon pumping (IABP). BACKGROUND: Use of IABP has been shown to increase CFV assessed by an invasive technique. The CFV in the left anterior descending coronary artery (LAD) can be measured by TTDE. METHODS: Coronary flow velocity in the distal LAD by TTDE was measured in 40 critically ill patients requiring IABP. All patients received emergency coronary angiography. Both CFV and pressure data were obtained during 1:2 balloon pumping. RESULTS: Adequate diastolic CFV recording was obtained in all patients. The IABP decreased systolic pressure and increased diastolic pressure. Average peak diastolic flow velocity and diastolic velocity time integral was 19 +/- 11 cm/s and 7.7 +/- 4.4 cm with non-augmented beat. These values were increased significantly (61 +/- 38%, 59 +/- 35%, p < 0.001) with augmented beat. Significant correlation was noted between % diastolic pressure augmentation and % increase in diastolic CFV (r = 0.62 to 0.69, p < 0.001). There was no significant difference in flow enhancement during IABP, irrespective to the proximal LAD stenosis severity (severe stenosis: 73 +/- 70%; intermediate stenosis: 61 +/- 29%; no significant stenosis: 58 +/- 29%; p = NS, analysis of variance). By continuous recording of CFV, the optimal timing of balloon control could be adjusted to maximize flow velocity during augmentation. CONCLUSIONS: Use of TTDE can be employed in monitoring CFV augmentation during IABP. The IABP produced significant distal flow enhancement even in patients with critical proximal stenosis. This totally noninvasive approach may help to optimize the benefits of IABP for coronary flow augmentation.

Which is the better method in detecting significant left anterior descending coronary artery stenosis during contrast-enhanced dobutamine stress echocardiography: coronary flow velocity reserve or wall-motion assessment?

The diagnostic accuracy of dobutamine stress echocardiography (DSE) depends on wall-motion assessment. Coronary flow velocity reserve (CFVR) during DSE can be measured by transthoracic Doppler echocardiography. To investigate comparative diagnostic accuracy between wall-motion and CFVR assessment in the detection of significant left anterior descending coronary artery (LAD) stenosis, 274 patients underwent both contrast-enhanced DSE and coronary angiography. Intravenous contrast agent, Levovist, was injected to enhance left ventricular endocardial border delineation and coronary flow velocity in the LAD. Wall motion was assessed by standard technique, and CFVR was calculated as coronary flow velocity at peak dobutamine stress divided by baseline coronary flow velocity by transthoracic Doppler echocardiography. CFVR could be successfully obtained in 232 patients (feasibility, 85%). After excluding 14 patients with isolated diagonal stenosis, CFVR was significantly lower in 65 patients with significant LAD stenosis than it was in 153 patients without stenosis (1.62 +/- 0.56 vs 2.72 +/- 0.94, P <.001). CFVR < or = 2.0 had a 75% sensitivity, a 81% specificity, and a 79% diagnostic accuracy for detecting significant LAD stenosis, and these values were comparable with those by wall-motion analysis (sensitivity, 78%; specificity, 89%; and diagnostic accuracy, 86%). The measurement of CFVR in the LAD during DSE was feasible and the diagnostic accuracy of CFVR was equivalent to wall-motion assessment in the detection of LAD stenosis.

Measurement of coronary flow velocity reserve in the posterior descending coronary artery by contrast-enhanced transthoracic Doppler echocardiography.

BACKGROUND: Although the measurement of coronary flow velocity (CFV) reserve (CFVR) in the left anterior descending coronary artery (LAD) by transthoracic Doppler echocardiography has been established, its success rate in the posterior descending coronary artery (PD) is still limited. OBJECTIVE: This study reports the feasibility and diagnostic accuracy of measuring CFVR in the PD by transthoracic Doppler echocardiography. METHODS: CFVR in both the distal LAD and the PD was measured in 151 consecutive patients before coronary angiography. PD flow was investigated under the guidance of a nondirectional Doppler color flow map with harmonic imaging in the modified apical 2-chamber view. Intravenous contrast agent, Levovist, was injected to enhance the CFV envelope at baseline and during hyperemia. RESULTS: CFVR was obtained in 145 patients in the LAD and 126 patients in the PD (P <.001). The success rate of CFVR measurement in the PD was significantly higher in the last 50 patients (88%) than it was in the first 50 patients (72%) (P <.05). CFVR in the PD was significantly lower for patients with significant stenosis of the artery supplying the PD than it was in those without stenosis (1.58 +/- 0.59 vs 2.45 +/- 0.72, P <.001). CFVR in the distal LAD was 1.40 +/- 0.62 in patients with significant LAD stenosis and 2.45 +/- 0.80 in those without stenosis (P <.001). If a cut-off value of CFVR < 2 was used, sensitivity, specificity, and accuracy for the diagnosis of significant (>50%) stenosis of the artery supplying the PD were 84%, 83%, and 83%, respectively, whereas for the LAD they were 91%, 75%, and 80%, respectively. CONCLUSIONS: Noninvasive measurement of CFVR in the PD could be obtained in the majority of unselected patients using a nondirectional Doppler color flow map and contrast-enhanced harmonic imaging. The diagnostic accuracy of CFVR in the PD is similar to that of the LAD and, hence, has a potential clinical use.

Relation between changes in coronary flow velocity and in wall motion for assessing contractile reserve during dobutamine stress echocardiography.

The purpose of this study was to determine the relationship between coronary flow velocity (CFV) measured by transthoracic Doppler echocardiography (TTDE) and wall motion during dobutamine stress echocardiography (DSE) in patients with resting wall motion abnormalities (WMAs). One hundred fifty patients with resting WMA in the left anterior descending coronary artery (LAD) territory underwent CFV recording in the distal LAD by TTDE during contrast-enhanced DSE. Regional wall motion, CFV, and CFV ratio, defined as a ratio of CFV at each stage of dobutamine stress to basal CFV, were obtained. Patients were divided into 4 groups (sustained improvement, biphasic response, worsening response, and no change). CFV was successfully recorded in 129 patients during DSE (86%). The mean value of basal CFV did not differ among the 4 groups. Although CFV ratio during DSE progressively increased in patients with sustained improvement, this increase was blunted with biphasic response and almost lost with worsening or no change response (P <.001, ANOVA). CFV ratio at peak stress was significantly higher in patients with sustained improvement (2.73 +/- 0.69) than that with the other 3 groups (P <.001). The value with biphasic response (1.68 +/- 0.56) was also higher than that with worsening (0.98 +/- 0.15, P <.005) and no change (1.28 +/- 0.38, P <.08). The simultaneous assessment of CFV and function in the LAD territory is feasible, and flow and function are closely correlated. TTDE provides flow information that may complement conventional echocardiographic assessment of myocardial viability.

Prognostic value of coronary flow reserve on long-term cardiovascular outcomes in patients with chronic kidney disease.

Cardiovascular (CV) diseases and chronic kidney disease (CKD) have common predisposing factors that subsequently cause microvascular dysfunction. In the absence of obstructive coronary artery disease, coronary flow reserve (CFR) represents the status of coronary microcirculation. This study aimed to investigate the prognostic importance of impaired CFR, as a marker of microvascular dysfunction, on long-term CV outcomes in patients with CKD. This study consisted of 139 patients with an estimated glomerular filtration rate of <60 ml/min/1.73 m(2) who had no obstructive narrowing of the left anterior descending artery. Transthoracic Doppler echocardiography was used to measure CFR in the left anterior descending artery. During the follow-up period (3.3 ± 1.6 years), CV events occurred in 26 patients (18.7%). Multivariate analysis that included CFR as a continuous value identified a serum level of C-reactive protein (hazard ratio 1.41, p = 0.03) and a value of CFR (hazard ratio 0.21, p = 0.009) as determinants for CV events, independent of traditional CV risk factors. Patients with a CFR of <2.0 had worse CV outcomes compared with those with a CFR of ≥2.0 (p <0.001). In conclusion, transthoracic Doppler echocardiographically derived CFR was useful for the risk stratification of CV outcomes in patients with CKD. The presence of microvascular dysfunction may play an important role in the association between CKD and future CV events.

Left ventricular discoordination index measured by speckle tracking strain rate imaging predicts reverse remodelling and survival after cardiac resynchronization therapy.

AIMS: This study aimed to evaluate the predictive value of a baseline speckle tracking strain rate imaging-derived discoordination index for response to cardiac resynchronization therapy (CRT). METHODS AND RESULTS: Ninety-seven patients with QRS ≥120 ms and left ventricular (LV) ejection fraction ≤35% were prospectively followed after CRT in the Mayo CRT Registry. The LV discoordination index (stretch/shortening or thinning/thickening during ejection) was calculated from three types of deformation, radial, circumferential, and longitudinal, using two-dimensional speckle tracking strain rate imaging. The benefit of CRT was evaluated by reverse remodelling (i.e. reduction of LV end-systolic volume ≥15% at 6-month follow-up) and survival. The optimal cut-off value of the baseline discoordination index in discriminating responders from non-responders was determined by receiver operating characteristic curve analysis. Significant differences in baseline indices between responders and non-responders were noted for radial and circumferential discoordination indices. A mid-ventricular radial discoordination index (RDI-M) >38% best predicted responders, especially in patients with ischaemic cardiomyopathy (area under the curve 0.86 for all patients, sensitivity 80%, and specificity 91%). Death occurred in 28 patients over a median follow-up of 3.2 years. When adjusted for confounding variables, lack of significant discoordination (RDI-M <38%) before CRT was associated with a particularly high mortality (hazard ratio 7.05, 95% confidence interval 2.45-26.0). CONCLUSION: LV discoordination assessed by speckle tracking RDI-M imaging was able to predict reverse remodelling at 6 months and survival of patients who received CRT.

Cardiac sympathetic reserve and response to cardiac resynchronization therapy.

BACKGROUND: The objective of the present study was to investigate the effect of cardiac resynchronization therapy (CRT) on cardiac autonomic function. METHODS AND RESULTS: This prospective study included 45 consecutive patients with heart failure who received CRT devices with defibrillator and 20 age-matched, healthy control subjects. At baseline and 3 months and 6 months after CRT, we assessed New York Heart Association (NYHA) class, 6-minute walk distance, plasma sympathetic biomarker nerve growth factor, echocardiography, heart rate variability and cardiac presynaptic sympathetic function determined by iodine 123 metaiodobenzylguanidine scintigraphy. After CRT, NYHA class improved by 1 class (P<0.001), and left ventricular ejection fraction increased by 8% (P<0.001). Along with improvement in the standard deviation of all normal-to-normal R-R intervals (85.63±31.66 ms versus 114.79±38.99 ms; P=0.004) and the standard deviation of the averaged normal-to-normal R-R intervals (82.62±23.03 ms versus 100.50±34.87 ms; P=0.004), the delayed heart/mediastinum (H/M) ratio increased (1.82 [0.58] versus 1.97 [0.59]; P=0.03), whereas the mean (SD) H/M washout rate was reduced (48% [19%] versus 37% [22%]; P=0.01). Twenty-two of 45 study patients responded to CRT, with a reduction of left ventricular end-systolic volume index >15%. Compared with nonresponders, responders had a higher delayed H/M ratio (2.11 versus 1.48; P=0.003) and lower H/M washout rate (37% versus 62%; P=0.003) at baseline. CONCLUSIONS: CRT improved sympathetic function. Cardiac sympathetic reserve may be a marker for the reversibility of failing myocardial function.

Independent predictors of survival in primary systemic (Al) amyloidosis, including cardiac biomarkers and left ventricular strain imaging: an observational cohort study.

BACKGROUND: The prognostic value of Doppler myocardial imaging, including myocardial velocity imaging, strain, and strain rate imaging, in patients with primary (AL) amyloidosis is uncertain. The aim of this longitudinal study was to identify independent predictors of survival, comparing clinical data, hematologic and cardiac biomarkers, and standard echocardiographic and Doppler myocardial imaging measures in a cohort of patients with AL amyloidosis. METHODS: A total of 249 consecutive patients with AL amyloidosis were prospectively enrolled. The primary end point was all-cause mortality, and during a median follow-up period of 18 months, 75 patients (30%) died. Clinical and electrocardiographic data, biomarkers (brain natriuretic peptide and cardiac troponin T) and standard echocardiographic and longitudinal systolic and diastolic Doppler myocardial imaging measurements for 16 left ventricular segments were tested as potential independent predictors of survival. RESULTS: Age (hazard ratio [HR], 1.03; P = .03), New York Heart Association class III or IV (HR, 2.47; P = .01), the presence of pleural effusion (HR, 1.79; P = .08), brain natriuretic peptide level (HR, 1.29; P = .01), ejection time (HR, 0.99; P = .13), and peak longitudinal systolic strain of the basal anteroseptal segment (HR, 1.05; P = .02) were independent predictors in the final model. CONCLUSIONS: Multivariate survival analysis identified independent predictors of clinical outcome in patients with AL amyloidosis: New York Heart Association class III or IV, presence of pleural effusion, brain natriuretic peptide level > 493 pg/mL, ejection time < 273 ms, and peak longitudinal systolic basal anteroseptal strain less negative than or equal to -7.5% defined a high-risk group of patients.

Dyssynchrony indices to predict response to cardiac resynchronization therapy: a comprehensive prospective single-center study.

BACKGROUND: Whether mechanical dyssynchrony indices predict reverse remodeling (RR) or clinical response to cardiac resynchronization therapy (CRT) remains controversial. This prospective study evaluated whether echocardiographic dyssynchrony indices predict RR or clinical response after CRT. METHODS AND RESULTS: Of 184 patients with heart failure with anticipated CRT who were prospectively enrolled, 131 with wide QRS and left ventricular ejection fraction <35% had 6-month follow-up after CRT implantation. Fourteen dyssynchrony indices (feasibility) by M-mode (94%), tissue velocity (96%), tissue Doppler strain (92%), 2D speckle strain (65% to 86%), 3D echocardiography (79%), and timing intervals (98%) were evaluated. RR (end-systolic volume reduction ≥15%) occurred in 55% and more frequently in patients without (71%) than in patients with (42%) ischemic cardiomyopathy (P=0.002). Overall, only M-mode, tissue Doppler strain, and total isovolumic time had a receiver operating characteristic area under the curve (AUC) greater than the line of no information, but none of these were strongly predictive of RR (AUC, 0.63 to 0.71). In nonischemic cardiomyopathy, no dyssynchrony index predicted RR. In ischemic cardiomyopathy, M-mode (AUC, 0.67), tissue Doppler strain (AUC, 0.79), and isovolumic time (AUC, 0.76) -derived indices predicted RR (P<0.05 for all), although the incremental value was modest. No indices predicted clinical response assessed by Minnesota Living with Heart Failure Questionnaire, 6-minute walk distance, and peak oxygen consumption. CONCLUSIONS: These findings are consistent with the Predictors of Response to CRT study and do not support use of these dyssynchrony indices to guide use of CRT.

Effects of cardiac resynchronization therapy on the Doppler Tei index.

BACKGROUND: The Tei index is an indicator of systolic and diastolic myocardial performance. We evaluated the Tei index in patients undergoing cardiac resynchronization therapy (CRT). METHODS: Forty-two patients were studied before CRT and 1 day and 6 months after CRT, comparing responders with nonresponders. RESULTS: The Tei index decreased 1 day after CRT (left ventricle [LV]: P < .001, right ventricle [RV]: P = .01) and remained lower at follow-up (LV and RV: P < .001 vs baseline). Responders had a higher LV Tei index at baseline (P = .003) and achieved a sustained improvement in Tei index at follow-up (LV: P < .001, RV: P = .002) in contrast with nonresponders (LV and RV: not significant). Baseline LV Tei index and change in LV Tei index were both correlated with LV end-systolic volume reduction after CRT (r = 0.52, P < .001, r = 0.43, P = .006). CONCLUSION: The baseline LV Tei index was significantly higher in responders and exhibited an acute and sustained improvement after CRT. The baseline RV Tei index was similar in responders and nonresponders but improved significantly only in responders.

Echocardiographic parameters of mechanical synchrony in healthy individuals.

Definition and validation of the ranges of normal values and agreement among echocardiographic measures of mechanical synchrony in healthy subjects are mostly lacking. The aims of this study were (1) to assess the ranges of normal values for 5 tissue Doppler imaging parameters, real-time 3-dimensional echocardiographic measures, and speckle-tracking measures of mechanical synchrony; (2) to evaluate interinstitutional variability; (3) to compare the ranges of normal values with those reported in previous research; and (4) to analyze the agreement among all parameters in the same healthy subject. Time to peak systolic velocity (Ts), the delay between Ts at the basal septal and lateral segments, peak velocity difference, strain derived by tissue Doppler imaging, Ts derived by tissue synchronization imaging, systolic synchrony index (SSI) derived by real-time 3-dimensional echocardiography, and longitudinal and radial strain derived by speckle tracking were prospectively collected and analyzed at 2 different institutions in 160 consecutive healthy subjects. The ranges of normal values, expressed as means +/- 2 SDs, were 30.32 +/- 29.36 ms for the SD of Ts, 15.51 +/- 99.88 ms for septal-lateral delay, 60.75 +/- 81.62 ms for peak velocity difference, 33.07 +/- 29.96 ms for tissue synchronization imaging, 34.16 +/- 23.26 ms for the SD of strain, 2.74 +/- 2.16% for SSI, 28.91 +/- 23.02 ms for the SD of longitudinal strain, and 10.4 +/- 6.31 ms for radial strain. There was large interinstitutional variability for all parameters. Three-dimensional SSI and radial strain were within the published upper range limit for healthy subjects. Ninety percent of healthy subjects were consistently classified to be synchronous by 1 parameter. With a composite index, more subjects than expected showed dyssynchrony (10% vs 2.5%). In conclusion, 3-dimensional SSI and radial strain were the most reproducible parameters and consistently discriminated normal healthy subjects from the cardiac resynchronization therapy volume responders.

Feasibility of prediction of myocardial viability with Doppler tissue imaging following percutaneous coronary intervention for ST elevation anterior myocardial infarction.

BACKGROUND: In patients with acute ST elevation myocardial infarction (STEMI), it is clinically important to determine the viability of akinetic segments soon after acute reperfusion therapy. The purpose of this study was to determine whether Doppler tissue imaging can predict myocardial viability in this clinical setting. METHODS: Twenty-four consecutive patients with the first acute anterior STEMI with akinetic apical segments were enrolled. Color-coded Doppler tissue imaging was performed. Myocardial velocity and strain values were determined from the septal and lateral walls at the normal basal and akinetic apical levels of the left ventricle on day 1 after percutaneous coronary intervention. The presence of isovolumic contraction of tissue velocity (TVivc) and strain rate (SRivc) were also determined. RESULTS: Twenty patients (mean age 62 +/- 15 years; 11 men) returned for follow-up echocardiography to assess wall motion recovery and viability. Ten patients who had recovery of akinetic segments showed lower baseline E/e' ratios than those without recovery (13.4 +/- 5.9 vs 19.1 +/- 5.7; P = .04). There was no difference between 19 recovered and 21 nonrecovered apical segments in all TV, SR, and strain values except early diastolic SR (SRe; 0.64 +/- 0.35 vs 0.43 +/- 0.25 s(-1); P = .04) at day 1. With a cutoff value of 0.32 s(-1) for SRe, the receiver operating characteristic curve for the prediction of recovery showed the highest sensitivity of 84%. The presence of TVivc had sensitivity and specificity of 79% and 33%, respectively, and for SRivc, sensitivity and specificity were 84% and 63%, respectively. With the combination of SRe and SRivc, specificity was increased to 78%. CONCLUSION: Patients with functional recovery from anterior STEMI showed better diastolic function, better SRe, and more isovolumic contraction. These parameters appear to be promising predictors for myocardial viability, and SR imaging was found to be a better method than TV imaging for the identification of viable myocardium in patients with STEMIs who underwent percutaneous coronary intervention.