Left atrial function by cardiac computed tomography is a predictor of heart failure and cardiovascular death.

OBJECTIVES: We sought to evaluate cardiac CT angiography (CCTA)-based assessment of left atrial (LA) function as a predictor of hospitalizations for heart failure (HF) and cardiovascular (CV) mortality. METHODS: LA function was evaluated using automatic derivation of LA volumes to calculate LA total emptying fraction (LATEF) in 788 consecutive patients with normal sinus rhythm who had undergone spiral CT scans. The relationship between LATEF evaluated by CCTA and the composite endpoint of admission for HF or CV mortality was analyzed using Cox models. RESULTS: During a median follow-up of 4 years, there were 100 events, 62 HF hospitalizations, and 38 cardiovascular deaths. Mean LATEF was 30.7 ± 10.7% and 40.5 ± 11.2% in patients with and without events, respectively (p < 0.0001). A high LATEF (upper tertile > 46%) was associated with a very low event rate (3.5% at 6 years [95% CI 1.7-7.1%]). The adjusted HR for HF or CV mortality was 4.37 (95% CI 1.99-9.60) in the lowest LATEF tertile, and 2.29 (95% CI 1.03-5.14) in the middle tertile, relative to the highest tertile. For the endpoint of HF alone, adjusted HR for the lowest LATEF tertile was 5.93 (95% CI 2.23-15.82) and for the middle tertile 2.89 (95% CI 1.06-7.86). The association of LATEF with outcome was similar for patients with both reduced and preserved left ventricular (LV) ejection fraction (Pinteraction = 0.724). Reduced LATEF was associated with a high event rate, even when coupled with normal LA volume. CONCLUSION: CCTA-derived LA function is a predictor of HF hospitalization or CV death, independent of clinical risk factors, LA volume, and LV systolic function. KEY POINTS: • Left atrial function can be automatically derived from cardiac CTA scans. • Cardiac CTA-derived left atrial function is a predictor of hospitalization for heart failure and cardiovascular death. • Evaluation of left atrial function could be useful in identifying patients at risk of heart failure.

Factors Associated with Left Ventricular Function Recovery in Patients with Atrial Fibrillation Related Cardiomyopathy.

BACKGROUND: The diagnosis of atrial fibrillation (AFIB) related cardiomyopathy relies on ruling out other causes for heart failure and on recovery of left ventricular (LV) function following return to sinus rhythm (SR). The pathophysiology underlying this pathology is multifactorial and not as completely known as the factors associated with functional recovery following the restoration of SR. OBJECTIVES: To identify clinical and echocardiographic factors associated with LV systolic function improvement following electrical cardioversion (CV) or after catheter ablation in patients with reduced ejection fraction (EF) related to AFIB and normal LV function at baseline. METHODS: The study included patients with preserved EF at baseline while in SR whose LVEF had reduced while in AFIB and improved LVEF following CV. We compared patients who had improved LVEF to normal baseline to those who did not. RESULTS: Eighty-six patients with AFIB had evidence of reduced LV systolic function and improved EF following return to SR. Fifty-five (64%) returned their EF to baseline. Patients with a history of ischemic heart disease (IHD), worse LV function, and larger LV size during AFIB were less likely to return to normal LV function. Multivariant analysis revealed that younger patients with slower ventricular response, a history of IHD, larger LV size, and more significant deterioration of LVEF during AFIB were less likely to recover their EF to baseline values. CONCLUSIONS: Patients with worse LV function and larger left ventricle during AFIB are less likely to return their baseline LV function following the restoration of sinus rhythm.

Accuracy of Diastolic Function by Cardiac Computed Tomography Relative to Echo-Doppler: Additive Clinical and Prognostic Value.

OBJECTIVES: We aimed to assess the agreement between cardiac computed tomography (CT) and echo for diagnosing advanced diastolic dysfunction (DD) and to assess the prognostic value of CT-based parameters. METHODS: One hundred one consecutive patients who had both CT and echo-Doppler within 1 month were included. Diastolic function was assessed by CT using a previously validated method, based on left atrial volume changes, and compared with echocardiography grades 0 to 3. Patients were followed up for a combined outcome of cardiac death and hospitalization for heart failure. RESULTS: By operating characteristic curve analysis, the best CT-based parameter for predicting advanced DD based on echo was left atrial total emptying fraction. Left atrial total emptying fraction <36% had sensitivity/specificity of 76%/86%. Agreement between echo and CT for detecting advanced (grades 2/3) DD was substantial (κ = 0.62, P < 0.0001). By Cox multivariate analysis, left atrial total emptying fraction was a powerful independent predictor of outcome at 3 years (hazard ratio, 8.0 [2.2-28.4]; P < 0.0001). CONCLUSIONS: Computed tomography-based assessment of DD has a good agreement with echo-Doppler-based results. Left atrial total emptying fraction seems to have a strong prognostic value.

Left-sided cardiac chamber evaluation using single-phase mid-diastolic coronary computed tomography angiography: derivation of normal values and comparison with conventional end-diastolic and end-systolic phases.

OBJECTIVES: With increasing use of prospective scanning techniques for cardiac computed tomography (CT), meaningful evaluation of chamber volumes is no longer possible due to lack of normal values. We aimed to define normal values for mid-diastolic (MD) chamber volumes and to determine their significance in comparison to maximum volumes. METHODS: Normal ranges at MD for left ventricular (LV) volume and mass and left atrial (LA) volume were determined from 101 normal controls. Thereafter, 109 consecutive CT scans, as well as 21 post-myocardial infarction patients, were analysed to determine the relationship between MD and maximum volumes. RESULTS: MD volumes correlated closely with maximal volumes (r = 0.99) for both LV and LA, and could estimate maximum volumes accurately. LV mass, measured at ED or MD, were very similar (r = 0.99). Abnormal MD volumes had excellent sensitivity and specificity to detect chamber enlargement based on maximal volumes (LV 86 %, 100 %, respectively; LA 100 %, 92 %, respectively). CONCLUSION: A single MD phase can identify patients with cardiomegaly or LV hypertrophy with a high degree of accuracy and MD volumes can give an accurate estimate of maximum LV and LA volumes. KEY POINTS: • Traditionally, helical cardiac CT provided clinically important information from chamber volume analysis. • Mid-diastolic left atrial and ventricular volumes correlate closely with maximal volumes. • We derive normal values for mid-diastolic left atrial and ventricular volumes and mass. • A single mid-diastolic phase can be used to identify chamber enlargement and hypertrophy.

Conduit Flow Compensates for Impaired Left Atrial Passive and Booster Functions in Advanced Diastolic Dysfunction.

BACKGROUND: Quantification of left atrial (LA) conduit function and its contribution to left ventricular (LV) filling is challenging because it requires simultaneous measurements of both LA and LV volumes. The functional relationship between LA conduit function and the severity of diastolic dysfunction remains controversial. We studied the role of LA conduit function in maintaining LV filling in advanced diastolic dysfunction. METHODS: We performed volumetric and flow analyses of LA function across the spectrum of LV diastolic dysfunction, derived from a set of consecutive patients undergoing multiphasic cardiac computed tomography scanning (n=489). From LA and LV time-volume curves, we calculated 3 volumetric components: (1) early passive emptying volume; (2) late active (booster) volume; and (3) conduit volume. Results were prospectively validated on a group of patients with severe aortic stenosis (n=110). RESULTS: The early passive filling progressively decreased with worsening diastolic function (P<0.001). The atrial booster contribution to stroke volume modestly increases with impaired relaxation (P=0.021) and declines with more advanced diastolic function (P<0.001), thus failing to compensate for the reduction in early filling. The conduit volume increased progressively (P<0.001), accounting for 75% of stroke volume (interquartile range, 63-81%) with a restrictive filling pattern, compensating for the reduction in both early and booster functions. Similar results were obtained in patients with severe aortic stenosis. The pulmonary artery systolic pressure increased in a near-linear fashion when the conduit contribution to stroke volume increased above 60%. Maximal conduit flow rate strongly correlated with mitral E-wave velocity (r=0.71; P<0.0001), indicating that the increase in mitral E wave in diastolic dysfunction represents the increased conduit flow. CONCLUSIONS: An increase in conduit volume contribution to stroke volume represents a compensatory mechanism to maintain LV filling in advanced diastolic dysfunction. The increase in conduit volume despite increasing LV diastolic pressures is accomplished by an increase in pulmonary venous pressure.

Pulmonary hypertension, right ventricular function, and clinical outcome in acute decompensated heart failure.

BACKGROUND: Pulmonary hypertension (PH) and right ventricular (RV) dysfunction have been associated with adverse outcome in patients with chronic heart failure. However, data are lacking in the setting of acute decompensated heart failure (ADHF). We sought to determine prognostic significance of PH in patients with ADHF and its interaction with RV function. METHODS: We studied 326 patients with ADHF. Pulmonary artery systolic pressure (PASP) and RV function were determined with the use of Doppler echocardiography, with PH defined as PASP >50 mm Hg. The primary end point was all-cause mortality during 1-year follow-up. RESULTS: PH was present in 139 patients (42.6%) and RV dysfunction in 83 (25.5%). The majority of patients (70%) with RV dysfunction had PH. Compared with patients with normal RV function and without PH, the adjusted hazard ratio (HR) for mortality was 2.41 (95% confidence interval [CI] 1.44-4.03; P = .001) in patients with both RV dysfunction and PH. Patients with normal RV function and PH had an intermediate risk (adjusted HR 1.78, 95% CI 1.11-2.86; P = .016). Notably, patients with RV dysfunction without PH were not at increased risk for 1-year mortality (HR 1.04, 95% CI 0.43-2.41; P = .94). PH and RV function data resulted in a net reclassification improvement of 22.25% (95% CI 7.2%-37.8%; P = .004). CONCLUSIONS: PH and RV function provide incremental prognostic information in ADHF. The combination of PH and RV dysfunction is particularly ominous. Thus, the estimation of PASP may be warranted in the standard assessment of ADHF.

Comparison Between Echocardiography and Cardiac Computed Tomography in the Evaluation of Diastolic Dysfunction and Prediction of Heart Failure.

Recent data indicate that left atrial (LA) function assessment by cardiac computed tomography (CT) is closely related to diastolic dysfunction (DD). Therefore, we aimed to perform a direct comparison between CT and echocardiography for diagnosis of advanced DD and prediction of future heart failure or cardiovascular death. We identified 340 patients who had both spiral cardiac CT and a proximate echocardiogram. LA total emptying fraction (LATEF), a measure of global LA function, was automatically calculated from CT data, as a surrogate for diastolic function and was compared with echocardiographic grades of diastolic function. The area under the receiver operating characteristic curve for LATEF to differentiate between advanced DD (grades 2 and 3) and all other grades was 0.84 (0.79 to 0.88). Over a median of 4 years, 69 events (admissions for heart failure and cardiovascular deaths) occurred. By multivariate Cox analysis, LATEF <40% provided incremental prognostic information after adjustments for advanced DD by echocardiography (hazard ratio 2.15, 95% confidence interval 1.13 to 3.94). There was a significant interaction (p = 0.03) between LATEF and echocardiography-based diastolic grades. Stratified analyses within the diastolic function groups revealed that LATEF <40% was equivalent to echocardiography in predicting events in the subgroup with advanced DD by echocardiography (p = 0.20) but was associated with a significantly higher event rates in patients with normal filling pressures (p = 0.0001) or indeterminate diastolic function (p = 0.04) by echocardiography. In conclusion, LA function derived from CT can accurately detect advanced DD diagnosed by echocardiography and has additive value to echocardiography-derived DD.

Frequency, characteristics, and outcome of patients with aortic stenosis, left ventricular dysfunction, and high (versus low) trans-aortic pressure gradient.

BACKGROUND: Trans-aortic pressure gradient in patients with aortic stenosis and left ventricular systolic dysfunction is typically low but occasionally high. OBJECTIVES: To examine the distribution of trans-aortic PG in patients with severe AS and severe LV dysfunction and compare the clinical and echocardiographic characteristics and outcome of patients with high versus low PG. METHODS: Using the echocardiographic laboratory database at our institution, 72 patients with severe AS (aortic valve area < or = 1.0 cm2) and severe LV dysfunction (LV ejection fraction < or = 30%) were identified. The characteristics and outcome of these patients were compared. RESULTS: PG was high (mean PG > or = 35 mmHg) in 32 patients (44.4%) and low (< 35 mmHg) in 40 (55.6%). Aortic valve area was slightly smaller in patients with high PG (0.63 + 0.15 vs. 0.75 +/- 0.16 cm2 in patients with low PG, P = 0.003), and LV ejection fraction was slightly higher in patients with high PG (26 +/- 5 vs. 22 +/- 5% in patients with low PG, P = 0.005). During a median follow-up period of 9 months 14 patients (19%) underwent aortic valve replacement and 46 patients (64%) died. Aortic valve replacement was associated with lower mortality (age and gender-adjusted hazard ratio 0.19, 95% confidence interval 0.05-0.82), whereas trans-aortic PG was not (P = 0.41). CONCLUSIONS: A large proportion of patients with severe AS have relatively high trans-aortic PG despite severe LV dysfunction, a finding partially related to more severe AS and better LV function. Trans-aortic PG is not related to outcome in these patients.

Risk Factors for the Development of Functional Tricuspid Regurgitation and Their Population-Attributable Fractions.

OBJECTIVES: The objective of this study was to determine risk factors for progression to hemodynamically significant tricuspid regurgitation (TR) and the population burden attributable to these risk factors. BACKGROUND: Few data are available with regard to risk factors associated with the development of hemodynamically significant functional TR. METHODS: A total of 1,552 subjects were studied beginning with an index echocardiogram demonstrating trivial or mild TR. Risk factors for progression to moderate or severe TR were determined by using logistic regression and classification trees. Population attributable fractions were calculated for each risk factor. RESULTS: During a median follow-up time of 38 (interquartile range [IQR]: 26 to 63) months, 292 patients (18.8%) developed moderate/severe TR. Independent predictors of TR progression were age, female sex, heart failure, pacemaker electrode, atrial fibrillation (AF), and indicators of left heart disease, including left atrial (LA) enlargement, elevated pulmonary artery pressure (PAP), and left-sided valvular disease. Classification and regression tree analysis demonstrated that the strongest predictors of TR progression were PAP of ≥36 mm Hg, LA enlargement, age ≥60 years, and AF. In the absence of these 4 risk factors, progression to moderate or severe TR occurred in ∼3% of patients. Age (28.4%) and PAP (20.5%) carried the highest population-attributable fractions for TR progression. In patients with TR progression, there was a marked concomitant increase of incident cases of elevated PAP (40%); mitral and aortic valve intervention (12%); reductions in left ventricular ejection fraction (19%), and new AF (32%) (all p < 0.01). CONCLUSIONS: TR progression is determined mainly by markers of increased left-sided filling pressures (PAP and LA enlargement), AF, and age. At the population level, age and PAP are the most important contributors to the burden of significant TR. TR progression entails a marked parallel increase in the severity of left-sided heart disease.

Automated 4-dimensional regional myocardial strain evaluation using cardiac computed tomography.

Evaluation of myocardial regional function is generally performed by visual "eyeballing" which is highly subjective. A robust quantifiable parameter of regional function is required to provide an objective, repeatable and comparable measure of myocardial performance. We aimed to evaluate the clinical utility of novel regional myocardial strain software from cardiac computed tomography (CT) datasets. 93 consecutive patients who had undergone retrospectively gated cardiac CT were evaluated by the software, which utilizes a finite element based tracking algorithm through the cardiac cycle. Circumferential (CS), longitudinal (LS) and radial (RS) strains were calculated for each of 16 myocardial segments and compared to a visual assessment, carried out by an experienced cardiologist on cine movies of standard "echo" views derived from the CT data. A subset of 37 cases was compared to speckle strain by echocardiography. The automated software performed successfully in 93/106 cases, with minimal human interaction. Peak CS, LS and RS all differentiated well between normal, hypokinetic and akinetic segments. Peak strains for akinetic segments were generally post-systolic, peaking at 50 ± 17% of the RR interval compared to 43 ± 9% for normokinetic segments. Using ROC analysis to test the ability to differentiate between normal and abnormal segments, the area under the curve was 0.84 ± 0.01 for CS, 0.80 ± 0.02 for RS and 0.68 ± 0.02 for LS. There was a moderate agreement with speckle strain. Automated 4D regional strain analysis of CT datasets shows a good correspondence to visual analysis and successfully differentiates between normal and abnormal segments, thus providing an objective quantifiable map of myocardial regional function.

Differential effects of afterload on left ventricular long- and short-axis function: insights from a clinical model of patients with aortic valve stenosis undergoing aortic valve replacement.

BACKGROUND: The effects of left ventricular (LV) afterload on longitudinal versus circumferential ventricular mechanics are largely unknown. Our objective was to examine changes in LV deformation before and early after aortic valve replacement (AVR) in patients with severe aortic valve stenosis (AS). METHODS: Paired echocardiographic studies before and early (7 +/- 3 days) after AVR were analyzed in 45 patients (age 67 +/- 12 years, 49% men) with severe AS and normal LV ejection fraction without segmental wall motion abnormalities. Longitudinal myocardial function was assessed from 3 apical views (average of 18 segments). Circumferential function was assessed at mid and apical levels (averaging 6 segments per view). Strain, strain rate (SR), and LV twist (relative rotation of the mid and apex) were measured using 2-dimensional strain software. RESULTS: Early post-AVR, (1) LV size and LV ejection fraction did not change; (2) longitudinal systolic strain, which was lower than normal before AVR, increased (-12.8 +/- 1.7 to -15.9 +/- 2.2, P < .05), whereas mid-LV circumferential strain, which was higher than normal, decreased (-27.0 +/- 5.1 to -22.3 +/- 4.9, P < .05); (3) longitudinal early diastolic SR increased (0.6 +/- 0.1 to 0.7 +/- 0.2, P < .05), whereas mid-LV circumferential diastolic SR decreased (1.2 +/- 0.5 to 1.0 +/- 0.3, P < .05); and (4) LV twist increased (3.7 degrees +/- 2.1 degrees to 6.1 degrees +/- 2.9 degrees , P < .05). CONCLUSIONS: Aortic valve stenosis causes differential changes in longitudinal and circumferential mechanics that partially normalize after AVR. These findings provide new insights into the mechanical adaptation of the LV to chronic afterload elevation and its response to unloading.

Quantitative evaluation of regional left ventricular function by multidetector computed tomography.

OBJECTIVE: : Because most contemporary workstations offer quantitative analysis of regional function by multidetector computed tomography, we aimed to establish typical values for normal, hypokinetic, and akinetic regions, and to establish optimal thresholds to differentiate between normal and abnormal values. METHODS: : For 33 patients, quantitative regional functional parameters were compared with visual analysis by both multidetector computed tomography and echocardiography. Normal values were established to normalize for segmental variability. Optimal thresholds were established to differentiate between normal and abnormal segments by receiver operating characteristic analysis. RESULTS: : Akinetic, hypokinetic, and normokinetic segments demonstrated significant differences (P < 0.0001) for end-systolic thickness (mean [95% confidence interval], 9.4 [4.5-14.3], 11.7 [7.2-16.2], and 14.3 mm [8.2-20.3 mm]), respectively; thickening, 24% [-22% to 71%], 45% [-16% to 106%], and 82% [10%-154%]), respectively; and motion, 3.5 [-2.0 to 8.9], 6.1 [-0.2 to 12.4], and 8.5 mm [1.8-15.3 mm], respectively). Thickening performed best with area under the curve of 0.87 and sensitivity equal to specificity of 82%. Intraobserver variability was good, but interobserver variability was only moderate. CONCLUSIONS: : Quantification of regional myocardial function can be performed to assist the physician in mapping left ventricular function.

Lack of Increased Cardiovascular Risk due to Functional Tricuspid Regurgitation in Patients with Left-Sided Heart Disease.

BACKGROUND: Significant tricuspid regurgitation (TR) is associated with higher risk for adverse cardiovascular outcomes. Left-sided heart disease (LHD) is a potentially important confounder of this association because it is strongly linked to both TR and clinical outcome. METHODS: We studied 5,886 patients who were followed for a period of 10 years after the index echocardiographic examination. The relationship between TR severity and the end point of admission for heart failure or cardiovascular mortality was analyzed using competing risk analysis, Cox model, and propensity score matching. RESULTS: Higher TR grade was associated with markers of LHD including left ventricular systolic dysfunction, valvular heart disease ≥ moderate, left atrial enlargement, and pulmonary hypertension (all P < .001). There was a significant interaction between TR and the presence of LHD with regard to the end point of heart failure in the competing risks model (P = .01) and the combined end point of heart failure and cardiovascular mortality (P = .02). In both models, moderate/severe TR was associated with higher risk for heart failure (hazard ratio [HR] = 3.10; 95% CI, 1.41-6.84; P = .005) and the combined end point of heart failure or cardiovascular mortality (HR = 2.75; 95% CI, 1.33-5.63, P = .006) only in patients without LHD. Propensity score matching yielded 350 patient pairs, of which 88% had LHD. The HR for heart failure or cardiovascular mortality at 10 years was 0.78 (95% CI, 0.56-1.08; P = .14) in the moderate/severe TR group as compared with the trivial/mild TR. CONCLUSIONS: Moderate or severe functional TR portends an increased risk for heart failure and cardiovascular mortality only when isolated, without concomitant LHD.

Tricuspid regurgitation in acute heart failure: is there any incremental risk?

Aim: Significant tricuspid regurgitation (TR) is common in heart failure (HF) and portends poor prognosis. We sought to determine whether the poor outcome results from the TR itself, or whether the TR is a surrogate marker of advanced left-sided myocardial or valvular heart disease. Methods and results: We studied 639 patients admitted for acute HF. The relationship between TR severity and the endpoint of readmission for HF or mortality was assessed after adjustment for multiple clinical and echocardiographic parameters. Higher TR grade was associated with higher congestion score and with other cardiac abnormalities including reduced left ventricular systolic function, moderate or severe mitral regurgitation, pulmonary hypertension (PH, defined as pulmonary artery systolic pressure ≥ 50 mmHg), and right ventricular dysfunction (all P < 0.001). Only 7% of patients with moderate or severe TR were free of other cardiac lesions. In adjusted models, moderate or severe TR was not associated with readmission for HF or mortality [hazard ratio (HR) 1.24, 95% confidence interval (95% CI) 0.97-1.57]. Patients with moderate/severe TR had similar risk for HF readmission or death compared with patients with trivial/mild TR when PH was not present (HR 1.17; 95% CI 0.78-1.75, P = 0.40) whereas the risk was higher in moderate/severe TR and PH (HR 1.78; 95% CI 1.34-2.36, P < 0.0001). Conclusion: Patients presenting with symptomatic HF and significant TR have multiple coexisting cardiac abnormalities. TR provides no additive risk in the presence of normal or mildly elevated pulmonary pressures. However, it is associated with excess rehospitalizations and mortality in patients with PH.

Risk Score for Prediction of 10-Year Atrial Fibrillation: A Community-Based Study.

PURPOSE: We used a large real-world data from community settings to develop and validate a 10-year risk score for new-onset atrial fibrillation (AF) and calculate its net benefit performance. METHODS: Multivariable Cox proportional hazards model was used to estimate effects of risk factors in the derivation cohort (n = 96,778) and to derive a risk equation. Measures of calibration and discrimination were calculated in the validation cohort (n = 48,404). RESULTS: Cumulative AF incidence rates for both the derivation and validation cohorts were 5.8% at 10 years. The final models included the following variables: age, sex, body mass index, history of treated hypertension, systolic blood pressure ≥ 160 mm Hg, chronic lung disease, history of myocardial infarction, history of peripheral arterial disease, heart failure and history of an inflammatory disease. There was a 27-fold difference (1.0% vs. 27.2%) in AF risk between the lowest (-1) and the highest (9) sum score. The c-statistic was 0.743 (95% confidence interval [CI], 0.737-0.749) for the derivation cohort and 0.749 (95% CI, 0.741-0.759) in the validation cohort. The risk equation was well calibrated, with predicted risks closely matching observed risks. Decision curve analysis displayed consistent positive net benefit of using the AF risk score for decision thresholds between 1 and 25% 10-year AF risk. CONCLUSION: We provide a simple score for the prediction of 10-year risk for AF. The score can be used to select patients at highest risk for treatments of modifiable risk factors, monitoring for sub-clinical AF detection or for clinical trials of primary prevention of AF.

Longitudinal two-dimensional strain for the diagnosis of left ventricular segmental dysfunction in patients with acute myocardial infarction.

The objectives of this study were to assess whether 2-dimensional strain (2DS) can detect left ventricular (LV) segmental dysfunction and to compare the diagnostic accuracy of various 2DS parameters. Multiple segmental longitudinal 2DS parameters were measured in 54 patients with a first myocardial infarction and single vessel coronary artery disease (age: 56 ± 11 years, 74% men, LV ejection fraction: 47 ± 10%, left anterior descending artery occlusion in 63%) and 14 age-matched subjects. 2DS parameters were compared to visual assessment of segmental function by multiple observers. Using receiver-operating characteristics analysis, the area under the curve (AUC) for peak systolic strain in diagnosing segmental dysfunction (akinetic or hypokinetic LV segments) and for diagnosing akinetic segments was 0.85 (95% confidence interval 0.83-0.88) and 0.88 (0.85-0.90), respectively (all P values < 0.001). Other 2DS strain parameters had similar (peak strain, peak strain rate) or lower (post-systolic shortening, time-to-peak strain, diastolic 2DS parameters) AUC values. An absolute value of peak systolic strain <16.8% (25th percentile in normal subjects) had high sensitivity (0.89) and negative predictive values (0.88), but low specificity (0.55) and positive predictive values (0.59) for diagnosing segmental dysfunction. Similar findings were observed using a cutoff of <13.3% (absolute value of 10th percentile) for diagnosing akinetic segments. Diagnostic accuracy was significantly worse for segments in which visual segmental assessment was discordant between observers. In conclusion, 2DS can be used to diagnose segmental LV dysfunction with high sensitivity but limited specificity. The diagnostic limitation of 2DS is partially related to the visual echocardiographic definition of segmental abnormality.

Ischemic mitral regurgitation and risk of heart failure after myocardial infarction.

BACKGROUND: The development of ischemic mitral regurgitation (MR) after myocardial infarction may impose hemodynamic load during a period of active left ventricular remodeling and promote heart failure (HF). However, few data are available on the relationship between ischemic MR and the long-term risk for HF. METHODS: We prospectively studied 1190 patients admitted for acute myocardial infarction. Mitral regurgitation was assessed by echocardiography and was considered mild, moderate, and severe when the regurgitant jet area occupied less than 20%, 20% to 40%, and greater than 40% of the left atrial area, respectively. The median duration of follow-up was 24 months (range, 6-48 months). RESULTS: Mild and moderate or severe ischemic MR was present in 39.7% and 6.3% of patients, respectively. After adjusting for ejection fraction and clinical variables (age, sex, Killip class, previous infarction, hypertension, diabetes mellitus, anterior infarction, ST-elevation infarction, and coronary revascularization), compared with patients without MR, the hazard ratios for HF were 2.8 (95% confidence interval [CI], 1.8-4.2; P<.001) and 3.6 (95% CI, 2.0-6.4; P<.001) in patients with mild and moderate or severe ischemic MR, respectively. The adjusted hazard ratios for death were 1.2 (95% CI, 0.8-1.8; P = .43) and 2.0 (95% CI, 1.2-3.4; P = .02) in patients with mild and moderate or severe MR, respectively. CONCLUSIONS: There is a graded independent association between the severity of ischemic MR and the development of HF after myocardial infarction. Even mild ischemic MR is associated with an increase in the risk of HF.

Time Dependence of the Effect of Right Ventricular Dysfunction on Clinical Outcomes After Myocardial Infarction: Role of Pulmonary Hypertension.

BACKGROUND: The clinical importance of right ventricular (RV) function in acute myocardial infarction is well recognized, but the impact of concomitant pulmonary hypertension (PH) has not been studied. METHODS AND RESULTS: We studied 1044 patients with acute myocardial infarction. Patients were classified into 4 groups according to the presence or absence of RV dysfunction and PH, defined as pulmonary artery systolic pressure >35 mm Hg: normal right ventricle without PH (n=509), normal right ventricle and PH (n=373), RV dysfunction without PH (n=64), and RV dysfunction and PH (n=98). A landmark analysis of early (admission to 30 days) and late (31 days to 8 years) mortality and readmission for heart failure was performed. In the first 30 days, RV dysfunction without PH was associated with a high mortality risk (adjusted hazard ratio 5.56, 95% CI 2.05-15.09, P<0.0001 compared with normal RV and no PH). In contrast, after 30 days, mortality rates among patients with RV dysfunction were increased only when PH was also present. Compared with patients having neither RV dysfunction nor PH, the adjusted hazard ratio for mortality was 1.44 (95% CI 0.68-3.04, P=0.34) in RV dysfunction without PH and 2.52 (95% CI 1.64-3.87, P<0.0001) in RV dysfunction with PH. PH with or without RV dysfunction was associated with increased risk for heart failure. CONCLUSION: In the absence of elevated pulmonary pressures, the risk associated with RV dysfunction after acute myocardial infarction is entirely confined to the first 30 days. Beyond 30 days, PH is the stronger risk factor for long-term mortality and readmission for heart failure.

Comparison of multidetector computed tomography versus echocardiography for assessing regional left ventricular function.

Multidetector computed tomography (MDCT) of the heart is a rapidly developing technique mainly used to evaluate the coronary arteries. However, it is also capable of evaluating ventricular function. It compares well with magnetic resonance imaging in calculating volumes and ejection fractions, but little has been reported on its ability to assess left ventricular (LV) segmental wall motion (LVSWM). This study compared semiquantitative LVSWM scoring by MDCT with echocardiography as the gold standard. Thirty-nine patients underwent MDCT angiography on a 16-slice scanner. Short- and long-axis LV slices were created at different phases of the cardiac cycle and visually evaluated using cine mode. Echocardiography was performed <48 hours after MDCT for 21 patients after acute myocardial infarctions and <1 month after MDCT for 18 patients without acute myocardial infarctions. Two blinded observers scored the MDCT and echocardiographic examinations according to the 16-segment model, scoring each segment from 1 (normal) to 3 (akinetic). Segmental dysfunction was found in 27 patients by echocardiography and in 24 by MDCT. An identical score was given by the 2 methods in 502 of 616 assessable segments (82%). Using a binary analysis (normal or abnormal), there was 89% agreement (546 of 616 segments). MDCT had a sensitivity of 66% (103 of 155 segments) and a specificity of 96% (443 of 461 segments) compared with echocardiography as the gold standard. Most disagreements occurred in the right coronary artery segments. In conclusion, MDCT can be used to evaluate LVSWM, showing good agreement with echocardiography, except for the right coronary artery segments.

Symptoms in severe aortic stenosis are associated with decreased compensatory circumferential myocardial mechanics.

BACKGROUND: Symptomatic patients with severe aortic stenosis (AS) demonstrate abnormal left ventricular (LV) mechanics. The aim of this study was to compare mechanics in asymptomatic and symptomatic patients with severe AS using two-dimensional myocardial strain imaging. METHODS: One hundred fifty-four patients with severe AS (aortic valve area ≤ 1.0 cm(2)) referred to a heart valve clinic from 2004 to 2011 were studied. Thirty patients were asymptomatic, with normal LV ejection fractions (≥ 55%), without other significant valvular disease or wall motion abnormalities. Thirty-two symptomatic patients who underwent early aortic valve replacement, with similar age, gender, LV ejection fraction, and aortic valve area, were selected for comparison. Both groups were also compared with 32 healthy subjects with similar age and gender distributions and normal echocardiographic results who served as controls. LV longitudinal and circumferential strain and rotation were measured using speckle-tracking software applied to archived echocardiographic studies. Conventional echocardiographic and myocardial mechanical parameters were compared among the study subgroups. RESULTS: Patients with asymptomatic severe AS demonstrated smaller reductions in longitudinal strain, higher (supernormal) apical circumferential strain (-38 ± 6% vs -35 ± 4%, P < .05), and extreme (supernormal) apical rotation (12.2 ± 4.9° vs 2.9 ± 1.7°, P < .0005) compared with symptomatic patients. Apical rotation < 6° was the single significant predictor of symptoms in logistic regression analysis of clinical, echocardiographic, and mechanical parameters. Twelve asymptomatic patients underwent eventual aortic valve replacement and showed decreases in strain and apical rotation compared with baseline values. CONCLUSIONS: Longitudinal strain was uniformly low in patients with severe AS and lower in those with symptoms. Compensatory circumferential myocardial mechanics (increased apical circumferential strain and rotation) were absent in symptomatic patients. Thus, myocardial mechanics may help in the follow-up of patients with severe AS and timing of valve surgery.