Reference values for echocardiographic measurements in urban and rural populations of differing ethnicity: the Strong Heart Study

Echocardiographic Measurements in Normal Healthy Adult Population of North India

BACKGROUND AND AIM

 Interpretation of imaging modalities depends on robust normal reference limits. Ethnicity is an essential determinant of cardiac chamber sizes. Though few studies from India have focused on this research, it has yet to include the Kashmiri population. We aimed to study normal echocardiographic values of healthy Kashmiri adults and compare them with Western and Indian studies.

METHODS

 It was a prospective observational study on healthy adults of Kashmir Valley. A comprehensive echocardiographic analysis following standardized protocols was performed.

RESULTS

 A total of 2245 study participants were analyzed. The mean age was 32.52±11.55 years. There were 1100 (49%) males. Males had higher absolute left ventricular volumes and mass, left atrial volumes, right ventricular diameter, and aortic size, while females had higher absolute left ventricular ejection fraction and early and late diastolic mitral inflow velocities. Males had higher indexed left ventricular end-systolic volume, while females had higher indexed left ventricular end diastole diameter, aorta diameter, right ventricle, and left and right atrial sizes. Left ventricular mass and diastolic parameters were significantly associated with age. Compared with the American Society of Echocardiography/European Association of Cardiovascular Imaging, absolute values of left ventricle size, volumes, mass, right ventricle size, aortic size, and left and right atrial size were higher than those in our study. Our study population had a higher left ventricle ejection fraction. Among indexed parameters, left ventricle volumes, left ventricle systolic diameter, aortic annulus, and left and right atrial volumes were still significantly higher in Western data. While comparing with Indian data, we noted significant regional differences.

CONCLUSION

 We provide normal reference values for our local population. We noted significant differences with Western as well as other Indian populations. Our study highlights the need for developing ethnic-specific reference values of various echocardiographic measurements.

Early start of enzyme replacement therapy in pediatric male patients with classical Fabry disease is associated with attenuated disease progression

BACKGROUND

Enzyme replacement therapy (ERT) slows disease progression of Fabry disease (FD), especially when initiated before the onset of irreversible organ damage. However, with the clinically asymptomatic progression of renal, cardiac and cerebral disease manifestations spanning decades, optimal timing of ERT initiation remains unclear.

METHODS

In this cross-sectional retrospective study, seven male FD patients with a classical disease phenotype (cFD) who started treatment with agalsidase-beta in childhood were evaluated after 10 years of treatment (median age at evaluation 24 years, range 14-26). Cardiac imaging (echocardiography and MRI), electrophysiological and biochemical data of these patients were compared to those of untreated male cFD patients (n = 23, median age 22 years, range 13-27).

RESULTS

Albuminuria was less common and less severe in treated patients (albumin to creatinine ratio, ACR 0-8.8 mg/mmol, median 0.4) compared to untreated patients (ACR 0-248 mg/mmol, median 3.7, p = 0.02). The treated group had a lower left ventricular mass, measured using echocardiography (median 80 g/m² versus 94 g/m², p = 0.02) and MRI (median 53 g/m² versus 68 g/m², p = 0.02). Myocardial fibrosis was absent in all included patients. eGFR was normal in all treated patients whereas 7/23 (30%) of untreated patients had abnormal eGFR. Cerebral manifestations did not differ.

CONCLUSIONS

Start of treatment with ERT before age 16, in male cFD patients is associated with reduced occurrence of renal and cardiac manifestations of FD, as assessed by intermediate endpoints. Confirmation that this approach delays or even prevents renal failure and cardiac events requires another decade of follow-up.

Prognostic value of left atrial size in hypertensive African Americans undergoing stress echocardiography

BACKGROUND

Left atrial (LA) enlargement is a marker of increased risk in the general population undergoing stress echocardiography. African American (AA) patients with hypertension are known to have less atrial remodeling than whites with hypertension. The prognostic impact of LA enlargement in AA with hypertension undergoing stress echocardiography is uncertain.

AIM

To investigate the prognostic value of LA size in hypertensive AA patients undergoing stress echocardiography.

METHODS

This retrospective outcomes study enrolled 583 consecutive hypertensive AA patients who underwent stress echocardiography over a 2.5-year period. Clinical characteristics including cardiovascular risk factors, stress and echocardiographic data were collected from the electronic health record of a large community hospital. Treadmill exercise and Dobutamine protocols were conducted based on standard practices. Patients were followed for all-cause mortality. The optimal cutoff value of antero-posterior LA diameter for mortality was assessed by receiver operating characteristic analysis. Cox regression was used to determine variables associated with outcome.

RESULTS

The mean age was 57 ± 12 years. LA dilatation was present in 9% (54) of patients (LA anteroposterior ≥ 2.4 cm/m²). There were 85 deaths (15%) during 4.5 ± 1.7 years of follow-up. LA diameter indexed for body surface area had an area under the curve of 0.72 ± 0.03 (optimal cut-point of 2.05 cm/m²). Variables independently associated with mortality included age [P = 0.004, hazard ratio (HR) 1.34 (1.10-1.64)], tobacco use [P = 0.001, HR 2.59 (1.51-4.44)], left ventricular hypertrophy [P = 0.001 , HR 2.14 (1.35-3.39)], Dobutamine stress [P = 0.003, HR 2.12 (1.29-3.47)], heart failure history [P = 0.031, HR 1.76 (1.05-2.94)], LA diameter ≥ 2.05 cm/m² [P = 0.027, HR 1.73 (1.06-2.82)], and an abnormal stress echocardiogram [P = 0.033, HR 1.67 (1.04-2.68)]. LA diameter as a continuous variable was also independently associated with mortality but LA size ≥ 2.40 cm/m² was not.

CONCLUSION

LA enlargement is infrequent in hypertensive AA patients when traditional reference values are used. LA enlargement is independently associated with mortality when a lower than “normal” threshold (≥ 2.05 cm/m²) is used.

A study on normal reference values of echocardiographic chamber dimensions in young eastern Indian adults

OBJECTIVE

Various studies have shown racial differences in adult cardiac chamber measurements by echocardiography. There is lack of any large scale data from India regarding the echocardiographic chamber measurements in cardiologically healthy individuals. In this study we present the normal reference values of echocardiographic chamber dimensions in young eastern Indian adults and compare it with the data in present guidelines and recent studies involving Indian subjects.

METHODS

This study was performed on 1377 healthy adults aged 18-35 years. Standard transthoracic echocardiographies were performed to obtain basic measurements. All measurements were indexed to body surface area.

RESULTS

The mean maximal aortic valve cusp separation (ACS) and indexed ACS were significantly more in females (p = 0.002, p = 0.03). Mean left ventricular (LV) ejection fraction (LVEF) and LV fractional shortening were marginally higher in females. Upper normal reference limit of LV end diastolic dimension (LVEdD) is slightly more for males. Comparing to ASE data, LVEdD, LV end systolic dimension, LV end diastolic volume, indexed LV end systolic volume, left atrial anteroposterior dimension, aortic root dimension and right ventricle outflow diameter were significantly lower in study population while LVEF was significantly higher (p < 0.0001).

CONCLUSION

The study reconfirms that Indian subjects have smaller cardiac chamber measurements compared to western population where as LVEF is higher in the Indian population and also demonstrates the wide variation of normal echocardiographic measurements within Indian subcontinent. No previous data from eastern India makes this research a singular experience.

Left atrial mass: relationship between gross anatomy and quantitative echocardiography

BACKGROUND

Left atrial (LA) enlargement is associated with increased risk of adverse cardiovascular outcomes. Unlike the left ventricular mass, LA mass has not been described. We sought to define the anatomic mass of the LA using anatomic specimens from autopsy. We hypothesized that LA mass could be estimated by echocardiography.

METHODS AND RESULTS

Using anatomic specimens of 22 subjects who died and underwent post mortem examination as well as echocardiogram, we defined normal LA mass by weighing anatomic specimens of those with normal LA volume on echocardiogram. Using 17 subjects with normal LA volume on echocardiogram, we found their LA mass on anatomic specimens to be 25.5 ± 6.3 grams (14.4 ± 3.2 g/m²). We developed an echocardiographic measure of LA mass and validated this measurement with paired LA anatomic specimens. We found the normal LA mass on echocardiogram to be 25.4 ± 6.3 g (14.4 ± 2.8 g/m²) which correlated well with anatomic specimens (β = 0.99; Confidence interval CI 0.6-1.4, P < .0001; Pearson correlation coefficient r = 0.83). Furthermore, we defined the normal LA volume to mass ratio as 1.38 ± 0.45.

CONCLUSIONS

LA mass is an additional parameter with which may contribute to the study of LA morphology.

Normal echocardiographic measurements in a Turkish population: The Healthy Heart ECHO-TR Trial

Objective:

Normal reference values for the cardiac chambers are widely based on cohorts from European or American populations. In this study, we aimed to obtain normal echocardiographic measurements of healthy Turkish volunteers to reveal the age, gender, and geographical region dependent differences between Turkish populations and other populations.

Methods:

Among 31 collaborating institutions from all regions of Turkey, 1154 healthy volunteers were enrolled in this study. Predefined protocols were used for all participants during echocardiographic examination. Blood biochemical parameters were also obtained for all patients on admission. The American Society of Echocardiography and European Association of Cardiovascular Imaging recommendations were used to assess the echocardiographic cardiac chamber quantification.

Results:

The study included 1154 volunteers (men: 609; women: 545), with a mean age of 33.5±11 years. Compared to men, women had a smaller body surface area, lower blood pressure and heart rate, lower hemoglobin, total cholesterol, lower low-density lipoprotein (LDL) levels, and higher high density lipoprotein (HDL) levels. Cardiac chambers were also smaller in women and their size varied with age. When we compared the regions in Turkey, the lowest values of left cardiac chamber indices were seen in the Marmara region and the highest values were observed in the Mediterranean region. Regarding the right cardiac indices, the Mediterranean region reported the lowest values, while the Black Sea region and the Eastern Anatolia region reported the highest values.

Conclusion:

This is the first study that evaluates the normal echocardiographic reference values for a healthy Turkish population. These results may provide important reference values that could be useful in routine clinical practice as well as in further clinical trials.

Normative reference ranges for echocardiographic chamber dimensions in a healthy Central European population: results from the Czech post-MONICA survey

Background

Normative reference values for echocardiographic chamber quantification are of great importance; however, this can be challenging. Our aim was to derive these values including degrees of abnormality from a random Central European population sample with a homogeneous subset of healthy subjects.

Methods

We analysed echocardiograms obtained in a randomly selected population sample during the Czech post-MONICA survey in 2007/2008. Overall, 1850 out of 2273 persons of the whole sample of three districts had adequate echocardiograms (81.4%). A healthy subgroup defined by the absence of known cardiovascular disease was used to define normal reference range limits (n = 575, median age 42 years [IQR 34–52], 57% females). The whole population sample with predefined percentile cut-offs was used to define degrees of abnormality.

Results

Left ventricular (LV) size tended to decrease with age, while LV mass increased with age in both males and females and in both the healthy and general populations. LV dimensions were larger in males, except for body surface area-indexed LV diameter. M-mode derived LV measurements were larger and LV mass higher compared to 2D measurements. Right ventricle basal dimension was larger in males.

Conclusions

Our study provides reference ranges for echocardiographic measurements obtained in a healthy subgroup derived from an epidemiological study of a Central European population. Where feasible, degrees of abnormality are provided based on the whole population sample including patients with disease. Our data show that age, gender and measurement method significantly affect cardiac dimensions and function and should be always taken into account.

Effect of Race on Echocardiographic Measures of Cardiac Structure and Function

The relations between race and cardiac structure and function are incompletely understood. We hypothesized that race-specific differences in echocardiography measurements exist. We compared the relation between echocardiography measurements and race among 12,429 nonobese adults without known cardiovascular disease who underwent echocardiography. We compared measurements between whites (n = 10,508), blacks (n = 792), Asians (n = 628), Hispanics (n = 315), Native Americans (n = 34), and multiracial/other (n = 152) cohorts. Multivariate analysis compared measurements indexed to body surface area (BSA) between races and adjusted for variables including age, gender, and mean blood pressure. Mean age was 46.9 ± 17.4 years and 60.5% were women. After multivariable adjustment and using whites as a baseline, there were significant differences (p <0.05) in left ventricular end-diastolic diameter/BSA for blacks (-0.5 mm/m²), Asians (0.4 mm/m²), Hispanics (0.2 mm/m²), and multiracial/others (0.1 mm/m²); septal wall thickness/BSA for blacks (0.4 mm/m²) and Asians (0.1 mm/m²); posterior wall thickness/BSA for blacks (0.4 mm/m²), Asians (0.1 mm/m²), Hispanics (0.04 mm/m²), and multiracial/others (0.03 mm/m²); left atrial diameter/BSA for Asians (0.2 mm/m²), Hispanics (0.3 mm/m²), and multiracial/others (0.1 mm/m²); septal and lateral e' for blacks (-0.7 cm/s; -0.9 cm/s); and peak tricuspid regurgitation gradient for blacks (4.3 mm Hg) and Asians (-0.9 mm Hg). Race is associated with significant differences in left ventricular size, left atrial size, mitral annular velocity, and tricuspid regurgitation gradient. Normal reference ranges for echocardiography measurements should utilize racially diverse cohorts to prevent misclassification of echocardiography findings based on race.

Obesity, Cardiac Remodeling, and Metabolic Profile: Validation of a New Simple Index beyond Body Mass Index

Aim:

The body mass index (BMI), the most used anthropometric index of obesity, has an important limitation, not taking into consideration the distribution of body fat. We developed a new simple index: the waist-corrected BMI (wBMI), calculated as waist circumference (WC) × BMI. The study aim was to assess the role of wBMI, compared to BMI, WC, and Waist-to-Height Ratio (WHtR) in predicting abnormal cardiac geometry, insulin resistance, increased arterial stiffness, and dyslipidemia.

Methods:

This was a cross-sectional study that included 805 patients referred to our Department of Preventive Cardiology for risk factors evaluation and treatment. Eleven echographic and laboratory parameters were determined, and receiver operating characteristic (ROC) curves were derived. Areas under ROC curves (AUC) were used to assess the accuracy of the four indexes to identify unfavorable characteristics.

Results:

There were 29% overweight, 59% obese, and 77% hypertensive patients. Of 11 echographic and laboratory parameters, wBMI, BMI, WHtR, and WC had the largest AUC for identifying 3, 1, 6, and 1 parameters, respectively, but with overlapping 95% confidence intervals. wBMI had the largest AUC for increased arterial stiffness and insulin resistance; also, it was superior to BMI for increased left atrial volume, relative wall thickness, and triglyceride level.

Conclusions:

In a large population with a high prevalence of obesity and hypertension, all four indexes were associated with unfavorable characteristics. wBMI has the theoretical advantage of taking into account simultaneously the global fat mass and distribution and might be useful for a better cardiovascular risk assessment.

Reduced exercise capacity in genetic haemochromatosis

BACKGROUND

Many patients with genetic haemochromatosis complain about fatigue and reduced physical capacity. Exercise capacity, however, has not been evaluated in larger series of haemochromatosis patients treated with repeated phlebotomy.

DESIGN AND METHODS

We performed exercise echocardiography in 152 treated haemochromatosis patients (48+/-13 years, 26% women) and 50 healthy blood donors (49+/-13 years, 30% women), who served as controls. Echocardiography was performed at rest and during exercise in a semiupright position on a chair bicycle, starting from 20 W, increasing by 20 W/min. Transmitral early and atrial velocity and isovolumic relaxation time were measured at each step. Ventilatory gas exchange was measured by the breath-to-breath-technique.

RESULTS

Compared with healthy controls, haemochromatosis patients were more obese and less trained. More of them smoked, and 17% had a history of cardiovascular or pulmonary disease. Adjusted for training, the left ventricular function and dimensions at rest did not differ between the groups. During exercise the haemochromatosis patients obtained a significantly lower peak oxygen (O2) uptake (28.1 vs. 34.4 ml/kg per min, P<0.001). In a multiple regression analysis haemochromatosis predicted lower peak O2 uptake independently of significant contributions of sex, age, and height, as well as of systolic blood pressure and log-transformed isovolumic relaxation time at peak exercise, whereas no independent association was found with weight or physical activity (multiple R=0.74, P<0.001). Adding genotype, s-ferritin, prevalence of smoking, or history of cardiopulmonary disease among the covariates in subsequent models did not change the results.

CONCLUSION

Genetic haemochromatosis, even when treated with regular phlebotomy, is associated with lower exercise capacity independently of other covariates of exercise capacity.

Comparison of Echocardiographic Measures in a Hispanic/Latino Population With the 2005 and 2015 American Society of Echocardiography Reference Limits (The Echocardiographic Study of Latinos)

BACKGROUND

Reference limits for echocardiographic quantification of cardiac chambers in Hispanics are not well studied.

METHODS AND RESULTS

We examined the reference values of left atrium and left ventricle (LV) structure in a large ethnically diverse Hispanic cohort. Two-dimensional transthoracic echocardiography was performed in 1818 participants of the Echocardiographic Study of Latinos (ECHO-SOL). Individuals with body mass index ≥30 kg/m(2), hypertension, diabetes mellitus, coronary artery disease, and atrial fibrillation were excluded leaving 525 participants defined as healthy reference cohort. We estimated 95th weighted percentiles of LV end systolic volume, LV end diastolic volume, relative wall and septal thickness, LV mass, and left atrial volume. We then used upper reference limits of the 2005 and 2015 American Society of Echocardiography (ASE) and 95th percentile of reference cohort to classify the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) target population into abnormal and normal. Reference limits were also calculated for each of 6 Hispanic origins. Using ASE 2015 defined reference values, we categorized 7%, 21%, 57%, and 17% of men and 18%, 29%, 60%, and 26% of women as having abnormal LV mass index, relative, septal, and posterior wall thickness, respectively. Conversely, 10% and 11% of men and 4% and 2% of women were classified as having abnormal end-diastolic volume and internal diameter by ASE 2015 cutoffs, respectively. Similar differences were found when we used 2005 ASE cutoffs. Several differences were noted in distribution of cardiac structure and volumes among various Hispanic/Latino origins. Cubans had highest values of echocardiographic measures, and Central Americans had the lowest.

CONCLUSIONS

This is the first large study that provides normal reference values for cardiac structure. It further demonstrates that a considerable segment of Hispanic/Latinos residing in the United States may be classified as having abnormal measures of cardiac chambers when 2015 and 2005 ASE reference cutoffs are used.

Normal echocardiographic measurements in Indian adults: How different are we from the western populations? A pilot study

This study sought to gain insights into the magnitude of error resulting in echocardiographic interpretations in Indian subjects by using western data as the reference. Standard transthoracic echocardiographic examination was performed in 100 healthy volunteers (mean age 34.0 ± 8.8 years, 59% males). Compared with the reference values published by the American Society of Echocardiography (ASE), our subjects had much smaller left ventricular (LV) end-diastolic dimension, end-systolic dimension, and end-diastolic volume (only 58%, 61%, and 61% of the subjects were having values within the ASE-defined normal ranges). Indexing to body surface area increased these proportions to 81%, 90%, and 68%, respectively. In contrast, LV ejection fraction and most of the measures of LV diastolic function coincided with the ASE-recommended age- and gender-specific values.

Effect of Preload Alterations on Left Ventricular Systolic Parameters Including Speckle-Tracking Echocardiography Radial Strain During General Anesthesia

OBJECTIVES

Frequently used parameters for evaluation of left ventricular systolic function are load-sensitive. However, the impact of preload alterations on speckle-tracking echocardiographic parameters during anesthesia has not been validated. Therefore, two-dimensional (2D) speckle-tracking echocardiography radial strain (RS) was assessed during general anesthesia, simulating 3 different preload conditions.

DESIGN

Single-center prospective observational study.

SETTING

University hospital.

PARTICIPANTS

Thirty-three patients with normal left ventricular systolic function undergoing major surgery.

INTERVENTIONS

Transgastric views of the midpapillary level of the left ventricle were acquired at 3 different positions.

MEASUREMENTS AND MAIN RESULTS

Fractional shortening (FS), fractional area change (FAC), and 2D speckle-tracking echocardiography RS were analyzed in the transgastric midpapillary view. Considerable correlation above 0.5 was found for FAC and FS in the zero and Trendelenburg positions (r = 0.629, r = 0.587), and for RS and FAC in the anti-Trendelenburg position (r = 0.518). In the repeated-measures analysis, significant differences among the values measured at the 3 positions were found for FAC and FS. For FAC, there were differences up to 2.8 percentage points between the anti-Trendelenburg position and the other 2 positions. For FS, only the difference between position zero and anti-Trendelenburg was significant, with an observed change of 1.66. Two-dimensional RS was not significantly different at all positions, with observed changes below 1 percentage point.

CONCLUSIONS

Alterations in preload did not result in clinically relevant changes of RS, FS, or FAC. Observed changes for RS were smallest; however, the variation of RS was larger than that of FS or FAC.

Echocardiographic assessment of left ventricular function in thyrotoxicosis and implications for the therapeutics of thyrotoxic cardiac disease

INTRODUCTION

Thyrotoxicosis is an endocrine disorder with prominent cardiovascular manifestations. Thyroid hormone acts through genomic and non-genomic mechanisms to regulate cardiac function. Echocardiography is a useful, non-invasive, easily accessible, and affordable tool for studying the structural and physiological function of the heart.

AIM

We studied thyrotoxicosis patients in a Nigerian Teaching Hospital and employed trans-thoracic echocardiography to find out if there were abnormalities in the hearts of these patients.

METHODS

Fifty adult thyrotoxicosis patients diagnosed with clinical and thyroid function tests in the medical out-patient unit of the hospital were recruited and we performed transthoracic echocardiography with a Sonos 2000 HP machine.

RESULTS

We documented the presence of abnormalities in the following proportion of thyrotoxicosis patients: left ventricular enhanced systolic function in 30%, enhanced diastolic function in 34%, diastolic dysfunction in 34%, heart failure with preserved ejection fraction in10%, heart failure with reduced ejection fraction in 6%, and left ventricular hypertrophy in 34%.

CONCLUSION

Echocardiography was useful in the stratification of cardiac function abnormalities and is indispensable as a guide in the choice of therapeutic options in patients with thyrocardiac disease. The finding of left ventricular enhanced systolic and diastolic functions signify early echocardiographic detectable cardiac abnormalities in thyrotoxicosis, and the clinical management includes the use of anti-thyroid drugs and β-adrenoceptor blockade. Diastolic dysfunction in thyrotoxicosis patients asymptomatic for cardiac disease should be treated with anti-thyroid drugs, and β-adrenoceptor blockade. The judicious application of clinical therapeutics will guide the use of anti-thyroid drugs, diuretics, digoxin, angiotensin inhibitors, and β-adrenoceptor blockade in the successful management of thyrotoxicosis patients with heart failure and reduced, preserved, or increased ejection fraction: parameters which are derived from echocardiography.

Risk factors for atrial fibrillation in patients with normal versus dilated left atrium (from the Atherosclerosis Risk in Communities Study)

Epidemiological data are limited regarding risk factors of atrial fibrillation (AF) in patients with normal-sized left atria (LA). We evaluated whether traditional risk factors of AF differ between patients with normal-sized and dilated LA. This is a cross sectional study of community-dwelling participants of the Atherosclerosis Risk in Communities study. LA volume index was measured by 2-dimensional echocardiography. LA volume index ≥29 mm(3)/m(2) defined dilated LA. Prevalent AF was defined by electrocardiogram and hospital discharge International Classification of Diseases-9 codes. Multivariate adjusted logistic regression analysis was used to examine whether magnitude of association of risk factors with AF differ by LA cavity size. Interaction of risk factors by LA cavity size was evaluated to determine significance of these differential associations. Of 5,496 participants (mean age 75 ± 5 years, women 58%), 1,230 participants (22%) had dilated LA. The prevalence of AF was 11% in patients with normal-sized LA and 15% in patients with dilated LA. Age >75 years (odds ratio [OR] 1.87, 95% confidence interval [CI] 1.49 to 2.35, interaction p = 0.12) and heart failure (OR 5.43, 95% CI 3.77 to 7.87, interaction p = 0.10) were stronger risk factors for AF in normal-sized LA than dilated LA. Female gender (OR 1.67, 95% CI 1.01 to 2.77, interaction p = 0.09), weight (OR 1.32, 95% CI 1.02 to 1.71, interaction p = 0.19), and alcohol use (OR 1.61, 95% CI 1.08 to 2.41, interaction p = 0.004) were stronger risk factors for AF in patients with dilated LA than normal-sized LA. In conclusion, risk factors of AF may differ by left ventricular cavity size.

Cardiac ventricular dimensions predict cognitive decline and cerebral blood flow abnormalities in aging men

BACKGROUND

The aims of this study are to examine possible associations between left cardiac ventricular measures in sixth decade and cognitive performance, both cross sectionally and longitudinally, and to examine if left cardiac ventricular measures could predict future changes in cerebral blood flow (CBF).

METHODS

211 elderly men from a cohort of the population study "Men born in 1914" completed M-mode echocardiography and a cognitive test battery at age 68. The cognitive test battery was repeated at age 81. CBF was estimated with 99mTc-HMPAO SPECT in 72 survivors at age 83. Cognitive performance at baseline and at 1st follow up and CBF at 1st follow up were analysed in relation to left ventricular internal dimension in diastole (LVIDd mm/m2) and fractional shortening (FS).

RESULTS

Subjects with enlarged LVIDd at age 68 had poorer results on verbal and speed-performance tests at baseline and on verbal and visuo-spatial tests 14 years later on. Low FS was associated with decreased results on visuo-spatial tests at baseline. There was an inverse relationship between LVIDd and both verbal and spatial ability at the baseline and after 14 years of follow-up. Normotensive men with lower FS had also decreased CBF in a majority of brain areas 14 years later.

CONCLUSIONS

Mild echocardiographic abnormalities in 68 ys.-old men, as increased LVIDd and lower FS, are associated with lower cognitive test results and may predict cognitive decline and silent cerebral perfusion abnormalities 14 years later.

Incremental value of biochemical and echocardiographic measures in prediction of ischemic stroke: the Strong Heart Study

BACKGROUND AND PURPOSE

American Indians have high rates of stroke. Improved risk stratification could enhance prevention, but the ability of biochemical and echocardiographic markers of preclinical disease to improve stroke prediction is not well-defined.

METHODS

We evaluated such markers as predictors of ischemic stroke in a community-based cohort of American Indians without prevalent cardiovascular or renal disease. Laboratory markers included C-reactive protein, fibrinogen, urine albumin-to-creatinine ratio, and glycohemoglobin (HbA1c), whereas echocardiographic parameters comprised left atrial diameter, left ventricular mass, mitral annular calcification, and the ratio of early to late mitral diastolic velocities. Predictive performance was judged by indices of discrimination, reclassification, and calibration.

RESULTS

After adjustment for standard risk factors, only HbA1c, albuminuria, and left atrial diameter were significantly associated with first ischemic stroke. Addition of HbA1c, although not urine albumin-to-creatinine ratio, to a basic clinical model significantly improved the C-statistic (0.714 versus 0.695; P=0.044), whereas left atrial diameter modestly enhanced integrated discrimination improvement (0.90%; P=0.004), but not the C-statistic (0.701; P=0.528). When combined with HbA1c, left atrial diameter further increased integrated discrimination improvement (1.81%; P<0.001) but not the C-statistic (0.716). No marker achieved significant net reclassification improvement.

CONCLUSIONS

In this cohort at high cardiometabolic risk, HbA1c emerged as the foremost predictor of ischemic stroke when added to traditional risk factors, affording substantially improved discrimination, with a more modest contribution for left atrial diameter. These findings bolster the role of HbA1c in cardiovascular risk assessment among persons with glycometabolic disorders and provide impetus for further study of the incremental value of echocardiography in high-risk populations.

Improved left ventricular mass quantification with partial voxel interpolation: in vivo and necropsy validation of a novel cardiac MRI segmentation algorithm

BACKGROUND

Cardiac magnetic resonance (CMR) typically quantifies LV mass (LVM) by means of manual planimetry (MP), but this approach is time-consuming and does not account for partial voxel components--myocardium admixed with blood in a single voxel. Automated segmentation (AS) can account for partial voxels, but this has not been used for LVM quantification. This study used automated CMR segmentation to test the influence of partial voxels on quantification of LVM.

METHODS AND RESULTS

LVM was quantified by AS and MP in 126 consecutive patients and 10 laboratory animals undergoing CMR. AS yielded both partial voxel (AS(PV)) and full voxel (AS(FV)) measurements. Methods were independently compared with LVM quantified on echocardiography (echo) and an ex vivo standard of LVM at necropsy. AS quantified LVM in all patients, yielding a 12-fold decrease in processing time versus MP (0:21±0:04 versus 4:18±1:02 minutes; P<0.001). AS(FV) mass (136±35 g) was slightly lower than MP (139±35; Δ=3±9 g, P<0.001). Both methods yielded similar proportions of patients with LV remodeling (P=0.73) and hypertrophy (P=1.00). Regarding partial voxel segmentation, AS(PV) yielded higher LVM (159±38 g) than MP (Δ=20±10 g) and AS(FV) (Δ=23±6 g, both P<0.001), corresponding to relative increases of 14% and 17%. In multivariable analysis, magnitude of difference between AS(PV) and AS(FV) correlated with larger voxel size (partial r=0.37, P<0.001) even after controlling for LV chamber volume (r=0.28, P=0.002) and total LVM (r=0.19, P=0.03). Among patients, AS(PV) yielded better agreement with echo (Δ=20±25 g) than did AS(FV) (Δ=43±24 g) or MP (Δ=40±22 g, both P<0.001). Among laboratory animals, AS(PV) and ex vivo results were similar (Δ=1±3 g, P=0.3), whereas AS(FV) (6±3 g, P<0.001) and MP (4±5 g, P=0.02) yielded small but significant differences with LVM at necropsy.

CONCLUSIONS

Automated segmentation of myocardial partial voxels yields a 14-17% increase in LVM versus full voxel segmentation, with increased differences correlated with lower spatial resolution. Partial voxel segmentation yields improved CMR agreement with echo and necropsy-verified LVM.

Prognostic impact of left ventricular mass severity according to the classification proposed by the American Society of Echocardiography/European Association of Echocardiography

BACKGROUND

The American Society of Echocardiography (ASE) and European Association of Echocardiography (EAE) recommend the use of quantitative estimation of left ventricular (LV) mass and defined partition values for mild, moderate, and severe hypertrophy. However, the prognostic implications associated with this categorization are unknown.

METHODS

In this observational cohort study of unselected adults undergoing echocardiography for any indication, LV hypertrophy was assessed using the ASE/EAE-recommended formula and measurement convention from LV linear dimensions indexed to body surface area. Mortality and incident hospitalizations for cardiovascular disease were the outcomes of this study.

RESULTS

Of 2,545 subjects (mean age, 61.9 ± 15.8 years; 56.3% women), 52.9% had normal LV mass, and 15.4% had mild, 12.1% moderate, and 19.6% severe LV hypertrophy. During a mean follow-up period of 2.5 ± 1.2 years, 121 deaths and 292 incident hospitalizations for cardiovascular disease occurred. In multivariate models including age, gender, LV ejection fraction, wall motion score index, significant valvular disease, and atrial fibrillation, the adjusted hazard ratios for death were 1.81 (95% confidence interval [CI], 1.03-3.20; P = .041) for mild, 2.31 (95% CI, 1.33-4.01; P = .003) for moderate, and 2.30 (95% CI, 1.39-3.79, P = .001) for severe LV hypertrophy. The adjusted hazard ratios for incident cardiovascular hospitalizations were 1.24 (95% CI, 0.84-1.82; P = .277) for mild, 2.02 (95% CI, 1.42-2.88; P = .0001) for moderate, and 2.38 (95% CI, 1.75-3.22, P < .0001) for severe LV hypertrophy. After adjustment for known risk predictors, there was a 1.3-fold risk for death and cardiovascular disease events per category of LV mass (P = .001).

CONCLUSIONS

In a cohort study of unselected adult outpatients, the categorization of LV mass according to the ASE/EAE recommendations offered prognostic information independently of age, gender, and other known predictors.

Geographic variation in left ventricular mass and mass index: a systematic review

Left ventricular (LV) hypertrophy, defined as an abnormal increase in LV mass (LVM), is an important prognostic indicator and therapeutic target. LVM is often divided by body surface area to derive indexed mass; however, this does not correctly identify pathological LV hypertrophy in all people, especially when body composition is altered, or in different ethnic groups. We evaluated published ranges of echocardiographic LVM in healthy adult populations from different countries, excluding control groups, and compared them with the American Society of Echocardiography reference ranges. A total of 33 studies met the inclusion criteria. In men and women, there was wide variation in the ranges of LVM with a tendency for the upper limit to increase geographically westward; this variation remained for indexed mass. Several ranges fell outside the upper reference limits: in men, 13 of the mass ranges and 16 of indexed mass; and in women, 8 mass and 16 indexed mass. This review has shown that current guidelines may need revision as some published series suggest that greater LV mass should be considered normal. This may be explained by ethnic differences and supports the need for widely applicable and ethnically diverse reference ranges to be established.

Relationship of left atrial enlargement to persistence or development of ECG left ventricular hypertrophy in hypertensive patients: implications for the development of new atrial fibrillation

BACKGROUND

Persistence and development of ECG left ventricular hypertrophy (LVH) by Cornell product criteria are associated with an increased risk of atrial fibrillation compared with regression or continued absence of LVH. We postulated that this association might be in part mediated via greater left atrial enlargement (LAE) in patients with new and persistent ECG LVH.

METHODS AND RESULTS

Baseline and third year ECG LVH and left atrial systolic diameter were examined in 663 patients in the Losartan Intervention For Endpoint reduction in hypertension echocardiographic substudy who were in sinus rhythm at baseline and had no history of atrial fibrillation. Left atrial systolic diameter was measured and considered enlarged if more than 3.8 cm in women or more than 4.2 cm in men. Cornell product LVH above 2440 mm-ms was considered consistent with LVH. After 3 years follow-up, 238 patients (35.9%) had continued absence of Cornell product LVH, 156 (23.5%) had regression of LVH, 236 (35.6%) had persistent LVH and 33 patients (5.0%) developed new ECG LVH. Compared with third year mean left atrial systolic dimension and prevalence of LAE in patients with continued absence of LVH (3.62+/-0.52 cm, 12.6%), there were step-wise increases in patients with regression of LVH (3.71+/-0.49 cm, 20.5%), persistence of LVH (3.82+/-0.57 cm, 32.2%) and development of new ECG LVH (3.91+/-0.42 cm, 36.4%, both P<0.001). After controlling for differences in age, sex, baseline SBP, BMI and Sokolow-Lyon voltage, randomized treatment allocation, change in DBP and SBP between baseline and third year and for isovolumic relaxation time and presence of an abnormal mitral E/A ratio at baseline and third year, the odds of having LAE were significantly increased in patients with persistent LVH (odds ratio 1.8, 95% confidence interval 1.1-3.2, P=0.043) or new LVH (odds ratio 3.1, 95% confidence interval 1.3-7.7, P=0.016), but not in patients with regression of Cornell product LVH (odds ratio 1.1, 95% confidence interval 0.6-2.0, P=0.860).

CONCLUSION

Persistence or development of new ECG LVH during antihypertensive therapy are associated with an increased risk of LAE after 3-year follow-up, whereas regression of ECG LVH is not associated with an increased risk of LAE. These findings provide insight into a possible mechanism by which changes in ECG LVH are associated with changing risk of developing atrial fibrillation.

Are normative values for LV geometry and mass based on fundamental imaging valid with use of harmonic imaging?

BACKGROUND

Multiple studies have reported echocardiographically determined normal reference values for left ventricular (LV) mass (LVM) derived using fundamental imaging (FI). Modern ultrasound systems now use harmonic imaging (HI) because of the improved LV endomyocardial definition. However, the 2005 American Society of Echocardiography (ASE) recommendations noted that the applicability of the reference values to HI-derived measurements has not been established.

METHODS

LVM and LV end-diastolic volume, diameter, and wall thickness were determined using HI in healthy subjects (n = 251), including normal-weight (NW) (body mass index < 25 kg/m², n = 149, 68% women) and otherwise healthy, overweight (OW) (body mass index ≥ 25 and <30 kg/m², n = 102, 41% women) groups. Measurements were compared with ASE-endorsed reference values. The agreement between FI and HI was determined in a prospective cohort of 51 subjects.

RESULTS

Two-dimensional (2D) derived LV volumes were similar between NW and OW subjects, although M-mode (MM)-derived LV diameters were slightly greater in OW subjects. 2D and MM-derived LVM was greater in OW compared with NW subjects, including after adjustment by height or height²·⁷; however, indexing to body surface area eliminated these differences. The partition values for abnormal 2D and MM-derived LVM were generally greater in NW and OW subjects of both sexes compared with the ASE-endorsed values (except MM-derived LVM in NW men). However, there were no significant differences in LVM determined by HI compared with FI in a prospectively studied cohort.

CONCLUSIONS

Reference values for LVM derived from NW and OW cohorts are generally higher than the ASE-endorsed referenced values. The difference between NW and ASE-endorsed values is unlikely to result from the use of HI rather than FI, because there is excellent agreement between these two imaging modalities. This study emphasizes the need to update normal reference values to reflect modern imaging methods.

In-treatment reduced left atrial diameter during antihypertensive treatment is associated with reduced new-onset atrial fibrillation in hypertensive patients with left ventricular hypertrophy: The LIFE Study

OBJECTIVE

It is unclear whether improvement of left atrial (LA) and ventricular (LV) structure results in reduction in new-onset atrial fibrillation (AF). The aim of the present study was to examine whether changes in-treatment LA diameter were related to changes in risk of new-onset AF.

METHODS

We followed 939 hypertensive patients with electrocardiographic LV hypertrophy randomized to atenolol or losartan-based regimens in the LIFE Study for a mean of 4.8 years with echocardiograms at enrolment and annually during treatment.

RESULTS

New-onset AF occurred in 46 patients (10.2/1000 patient-years of follow-up). At baseline, patients with new-onset AF were older, had higher systolic blood pressure and heart rate as well as higher prevalence of LA dilatation, but had similar prevalences of LV hypertrophy and mitral or aortic valve disease. In univariate Cox analysis baseline LA diameter (HR=4.67 per cm increase [95% CI 2.86-7.65], p<0.001) and LV mass index (HR=1.11 per 10 g/m(2) increase [95% CI 1.02-1.22], p<0.05) both predicted new-onset AF. In multivariate analysis, increased baseline LA diameter increased the risk of new-onset AF (HR=5.16 per cm [95% CI 2.85-9.35], p<0.001) whereas reduction of in-treatment LA diameter reduced the risk (HR=0.21 per cm lower LA diameter during treatment [95% CI 0.14-0.32], p<0.001) with adjustment for in-treatment LV mass in-treatment systolic blood pressure, age and Framingham risk score.

CONCLUSION

LA diameter at baseline and during antihypertensive treatment were equally strong predictors of new-onset AF independent of the level of arterial pressure, LV mass and other covariates. Prevention of AF during antihypertensive treatment may be improved by antihypertensive therapy that reduces LA size in addition to controlling blood pressure.

Distribution and categorization of left ventricular measurements in the general population: results from the population-based Gutenberg Heart Study

BACKGROUND

Echocardiography, the dominant imaging modality for quantification of left ventricular metrics, has undergone continuing development in the past few decades. However, given the lack of population-based data, current guidelines are still based on restricted and small data sets analyzed with methods including expert opinion. This work presents empirically derived reference values from a large-scale, epidemiologic study conducted with state-of-the-art imaging technology and methods.

METHODS AND RESULTS

The distribution of echocardiographic measurements of the left ventricle was analyzed in a population-based sample of 5000 mid-Europeans from the Gutenberg Heart Study in Germany. The randomly selected, noninstitutionalized sample provides data on apparently healthy individuals, as well as on those with prevalent disease. Standardized echocardiograms were recorded in a comprehensive data set at a single site with centralized training and certification of sonographers. Sex-specific reference limits and categories indicating the grade of deviation from the reference were calculated, and nomograms were created by quantile regression. Detailed information is given on the association between left ventricular geometry and age.

CONCLUSIONS

The rapidly evolving echocardiographic technology with persistent improvements in image quality and new measurement conventions require the evaluation of new reference limits for left ventricular metrics. The present investigation formulates reference limits and nomograms from state-of-the-art technology and methods based on a large population-based data set. The distribution of echocardiographic measures of left ventricular geometry presents, in part, nonlinear associations with age, which should be the subject of future investigations.

Left ventricular diastolic size in patients with normal ejection fraction and elevated left filling pressures

OBJECTIVE

To evaluate the left-ventricular diastolic chamber size in patients with a normal ejection fraction and elevated left-sided filling pressures.

BACKGROUND

The consensus view that patients with normal left ventricular ejection fraction (LVEF) and elevated left-sided filling pressures have a normal left ventricular diastolic size is a point of controversy.

METHODS

We reviewed the coded database of echocardiographic studies performed at one institution between July 2007 and July 2008. We performed a retrospective descriptive study of 35 patients with normal ejection fraction (> or = 55%) and elevated left-sided filling pressures. We looked at their left ventricular internal diastolic diameter (LVIDD).

RESULTS

Our population had a high prevalence of hypertension (100%), obesity (63%), diabetes (40%), chronic kidney disease (51%), coronary artery disease (25%), anemia (43%), and left ventricular hypertrophy (65%). Clinical diagnosis of heart failure was documented in 63% of the patients. LVIDD was mildly increased in comparison to a normal historical population: 4.85 + or - 0.5 cm for females, 5.3 + or - 0.5 cm for males, as compared to 4.6 + or - 0.3 cm for normal females (P = 0.045) and 5 + or - 0.4 cm for normal males (P < 0.001). However, the distribution of the indexed LVIDDs in these patients was comparable to the normal population (2.6 + or - 0.4 cm/m(2) for the study population, as compared to 2.7 + or - 0.2 cm/m(2) for the normal population, P = 0.16).

CONCLUSION

In a population of patients with a normal LVEF and high left ventricular filling pressures, the indexed LV diastolic size is not increased in comparison to a normal population. (Echocardiography 2010;27:501-504).

Echocardiographic Values for Cardiac Dimensions and Left Ventricular Mass of Normal Chinese Adults

Studies evaluating potential differences in normal cardiac dimensions and body mass indices of various ethnic populations using 2D echocardiography have reported variations based on gender and ethnicity. With the currently accepted echocardiographic reference values from US studies, and the limited information available on Chinese populations, the aim of this pilot study was to determine the normal cardiac dimensions and left ventricular mass of adult Chinese using 2D-guided M-mode echocardiography. Of healthy Chinese adults (age 18 years and older) living in Hong Kong, 57 suitable participants (26 men, aged 35.7 ± 10.2 years; 31 women, aged 44.2 ± 8.5 years) were recruited. The results indicated that the mean sizes of the aortic root, left ventricular wall thickness, and left ventricular mass of Chinese men were significantly larger than those of Chinese women. Left ventricular mass of the Chinese sample population (men, 116.0 ± 20.6 g; women, 99.8 ± 20.9 g) was significantly smaller than US-based studies. The conclusions drawn are of clinical importance, especially in the assessment and management of hypertensive cardiac effects. The results of this study strongly indicate the need for a large-scale study to further establish ethnic-specific and gender-specific echocardiographic reference values for the Chinese population.

Impact of Mild Hypertension on Left Atrial Size and Function

Background— Left atrial (LA) enlargement has been documented to occur in moderate and severe hypertension.

Methods and Results— One hundred twelve mild hypertension patients were prospectively recruited and compared with 198 healthy volunteers. All recruits had a transthoracic echocardiogram. Maximum LA biplane volume, minimum LA biplane volume, and pre ‘p’-LA biplane volume were measured, and left atrial passive, active emptying, and conduit volumes were calculated at baseline and in a subgroup of patients after 12 months. After adjusting for age, gender, and body mass index, maximum LA biplane volume, pre ‘p’-LA biplane volume, and their indexed volumes were increased in the hypertension group. Active emptying volume and fraction were significantly increased in the hypertension group, with no change in conduit and passive volumes. Subgroup analysis comparing hypertensives with normal/mildly increased left ventricular mass (group 1) with those with moderate/severely increased left ventricular mass (group 2) at baseline demonstrated that maximum LA biplane volume (62.8�17.9 mL versus 45.4�13.7 mL; P <0.001) was significantly increased in group 2. Active emptying volume was also increased.

Conclusion— Even mild hypertension seems to be associated with a reduction in early diastolic filling. This results in augmented late left ventricular diastolic filling due to active atrial contraction and may be the mechanism for the increase in left atrial size.

Determinants of left ventricular mass and presence of metabolic risk factors in normotensive individuals

BACKGROUND

Insulin resistance and obesity are recognized as left ventricular (LV) mass determinants independent of blood pressure (BP). Prevalence of LV hypertrophy (LVH) and the relationship between LV mass to body composition and metabolic variables were evaluated in normotensive individuals as participants of a population-based study.

METHODS

LV mass was measured using the second harmonic image by M-mode 2D guided echocardiography in 326 normotensive subjects (mean 47+/-9.4 years). Fasting serum lipids and glucose, BP, body composition and waist circumference (WC) were recorded during a clinic visit.

RESULTS

Applying a normalization criterion not related to body weight (g/height raised to the power 2.7) and the cut-off points of 47.7 (men) and 46.6 g/m(2.7) (women), LVH was found in 7.9% of the sample. Univariate analysis showed LV mass (g/m(2.7)) related to age, body mass index (BMI), WC, fat and lean body mass, systolic and diastolic BP, and metabolic variables (cholesterol, HDL-c, triglycerides and glucose). In multivariate analysis only BMI and age-adjusted systolic BP remained as independent predictors of LV mass, explaining 31% and 5% of its variability. Removing BMI from the model, WC, age-adjusted systolic BP and lean mass remained independent predictors, explaining 25.0%, 4.0% and 1.5% of LV mass variability, respectively. After sex stratification, LV mass predictors were WC (8%) and systolic BP (5%) in men and WC (36%) and systolic BP (3%) in women.

CONCLUSION

BMI in general and particularly increased abdominal adiposity (WC as surrogate) seems to account for most of LV mass increase in normotensive individuals, mainly in women.

Reference values for quantitative left ventricular and left atrial measurements in cardiac computed tomography

To assess reference values for left ventricular (LV) and left atrial (LA) dimensions, global LV function, and LV-myocardial mass for cardiac CT. We examined 120 subjects undergoing a coronary angiography using 64-slice and dual-source CT. All individuals had a low cardiovascular risk, normal ECG, negative biomarkers, and a normal cardiac CT examination. All subjects had a negative medical history of cardiovascular disease both on admission and at clinical 6-month follow-up. The following measurements were obtained: septal wall thickness (SWT), posterior wall thickness (PWT), LV inner diameter (LVID), LA anterior posterior diameter (LAD(sys)), end-systolic volume (ESV), and end-diastolic volume (EDV), LV-myocardial mass (LVMM). We found significant gender-related differences for all LV dimensions (SWT(sys), SWT(dia),PWT(sys),PWT(dia),LVID(sys),LVID(dia)). LAD(sys) showed no significant difference between males and females. Significant differences were found for global LV functional parameters including ESV, EDV, and SV, whereas no significant differences were found for the EF. LV-myocardial mass parameters showed significant gender-related differences. No significant correlation was found between any of these parameters and age. All data were transferred to percentile ranks. This study provides gender-related reference values and percentiles for LV and LA quantitative measurements for cardiac CT and should assist in interpreting results.

Ventricular Structure and Function in Hypertensive Participants With Heart Failure and a Normal Ejection Fraction

OBJECTIVES

The purpose of this study was to evaluate left ventricular (LV) size and structure in elderly subjects with hypertension (HTN) and heart failure who have a normal ejection fraction (HFNEF) in a large population-based sample.

BACKGROUND

The pathophysiology of HFNEF is incompletely understood but is generally attributed to LV diastolic dysfunction with normal or reduced LV diastolic chamber size despite greater than normal filling pressures.

METHODS

In the Cardiovascular Health Study (n = 5,888), demographic and clinical characteristics and ventricular structure and function were compared in healthy normal subjects (healthy; n = 499), subjects with HTN but not heart failure (HTN; n = 2,184), and subjects with HTN and HFNEF (HFNEF; n = 167).

RESULTS

Subjects with HFNEF were older, more obese, and more often African American than healthy and HTN subjects and had a higher prevalence of diabetes, coronary heart disease, and anemia than HTN subjects. Serum creatinine and cystatin-C were increased in HFNEF subjects. Average LV diastolic dimension was significantly increased in HFNEF subjects (5.2 +/- 0.8 cm) compared with healthy (4.8 +/- 0.6 cm) and HTN (4.9 +/- 0.6 cm) subjects. As a result, average calculated stroke volume (89 +/- 25 ml vs. 78 +/- 20 ml and 80 +/- 20 ml) and cardiac output (6.0 +/- 2.0 l/min vs. 4.8 +/- 1.3 l/min and 5.1 +/- 1.4 l/min) were increased in HFNEF compared with healthy and HTN subjects, respectively.

CONCLUSIONS

As a group, HFNEF subjects have increased LV diastolic diameter and increased calculated stroke volume. They also have increased prevalence of multiple comorbidities, including anemia, renal dysfunction, and obesity, that can cause volume overload. These data suggest that extracardiac factors, via volume overload, may contribute to the pathophysiology of HFNEF in the elderly.

Left Atrial Size and Risk of Major Cardiovascular Events During Antihypertensive Treatment

The influence of left atrial size on cardiovascular events during antihypertensive treatment has not been reported previously from a long-term, prospective, randomized hypertension treatment trial. We recorded left atrial diameter by annual echocardiography and cardiovascular events in 881 hypertensive patients (41% women) with electrocardiographic left ventricular hypertrophy aged 55 to 80 (mean: 66) years during a mean of 4.8 years of randomized losartan- or atenolol-based treatment in the Losartan Intervention for Endpoint Reduction in Hypertension Study. During follow-up, a total of 88 primary end points (combined cardiovascular death, myocardial infarction, or stroke) occurred. In Cox regression, baseline left atrial diameter/height predicted incidence of cardiovascular events (hazard ratio: 1.98 per cm/m [95% CI: 1.02 to 3.83 per cm/m]; P =0.042) adjusted for significant effects of Framingham risk score and history of atrial fibrillation. Greater left atrial diameter reduction during follow-up was associated with greater reduction in left ventricular hypertrophy, absence of new-onset atrial fibrillation or mitral regurgitation during follow-up, and losartan-based treatment (B=−0.13±0.03 cm/m; P <0.001) in multiple linear regression, adjusting for baseline left atrial diameter/height. However, in time-varying Cox regression analysis, left atrial diameter reduction was not independent of left ventricular hypertrophy regression in predicting cardiovascular events during follow-up. In conclusion, left atrial diameter/height predicts risk of cardiovascular events independent of other clinical risk factors in hypertensive patients with left ventricular hypertrophy and may be useful in pretreatment clinical assessment of cardiovascular risk in these patients.

Coronary flow reserve impairment predicts cardiac events in heart transplant patients with preserved left ventricular function

BACKGROUND

The impact of allograft vasculopathy on the coronary circulation and consequently on cardiac outcome may be expressed by coronary flow reserve (CFR) impairment. Therefore, we aimed to evaluate CFR and its relation to cardiac events in heart transplant patients.

METHODS

Twenty-three patients, 2 female, with left ventricular ejection fraction >45% were studied 76+/-30 months after heart transplantation. They were divided into 2 groups according to coronary angiography: Group A, 10 patients with significant coronary artery disease (stenosis> or =50%) and group B, 13 patients without significant stenosis. Twenty healthy subjects, 13 female, served as controls. Coronary flow velocity reserve (CFVR) was assessed by transesophageal echocardiography and calculated as the ratio of maximal (i.v. adenosine, 140 microg/kg/min) to baseline coronary velocities. Patients were followed for a mean of 25 months for cardiac events.

RESULTS

Compared to controls, heart transplant groups showed significantly higher baseline coronary flow velocities (51+/-27, 38+/-12 and 32+/-12 cm/s, respectively) and lower maximal coronary velocities (90+/-52, 112+/-33 and 118+/-24 cm/s), resulting in a reduced CFVR (1.9+/-1.0, 3.0+/-0.5 and 3.8+/-1.2). Multivariate analysis identified heart transplantation and epicardial coronary artery disease as the only variables independently related to CFVR. Hypertension was positively related to baseline while diabetes inversely related to maximal coronary flow velocities. A CFVR <2.3 was a marker for cardiac events (4 deaths, 1 heart failure).

CONCLUSION

CFVR impairment, particularly in the presence of epicardial coronary artery disease, follows heart transplantation and is associated with a worse outcome.