Normative values of cardiac chamber dimensions and global longitudinal strain in Indians: the Indian Normative Data of Echocardiography Analyzed (INDEA) study.

Ethnic-specific normal reference ranges for various echocardiographic measurements are essential for accurate diagnostic interpretation and clinical decision-making. Unfortunately, such normative data for Indians is lacking. A total of 880 healthy volunteers (mean age 39.7 ± 12.3 years, 63.8% men) from six centers across different regions of India were enrolled in this study. Comprehensive transthoracic echocardiographic study was performed in all subjects, in accordance with the existing guideline recommendations. Cardiac chamber dimensions [Left ventricular (LV) end-diastolic diameter and volume; right ventricular (RV) basal diameter, left atrial volume] were obtained and indexed to body surface area. LV ejection fraction, LV global longitudinal strain (LVGLS) and measures of RV systolic function were also obtained. The subjects were divided into 3 age groups (35 years or less, 36-55 years and 56 years or above) for analysis. Age- and gender-specific reference values for various clinically relevant echocardiographic parameters were derived. Compared with women, men had larger cardiac chamber dimensions and volumes, but not when indexed. In contrast, the women had higher LV systolic function, but right ventricular systolic function was not different. The indexed LV volumes in our study were much smaller than those recommended in the American Society of Echocardiography (ASE)/European Association of Cardiovascular Imaging (EACVI) 2015 chamber quantification guidelines but were similar to those reported in the Indian patients included in the recent World Alliance Societies of Echocardiography (WASE) Normal Values Study. LVGLS was also comparable with the WASE data. INDEA study is the first, multi-centric study to provide normal echocardiographic references values for Indian adults. Our findings underscore the need to follow India-specific reference values, instead of those recommended by the ASE/EACVI, which are largely applicable to the western populations.

The use of multi-site photoplethysmography (PPG) as a screening tool for coronary arterial disease and atherosclerosis.

Objective. We present the design and validation of a non-invasive smart-phone based screening tool for atherosclerosis and coronary arterial disease (CAD), which is the leading cause of mortality worldwide.Approach. We designed a three-channel photoplethysmography (PPG) device that connects to a smart phone application for measuring pulse transit time (PTT) and pulse wave velocity (PWV) using PPG probes that are simultaneously clipped onto to the ear, index finger, and big toe, respectively. Validation was performed through a clinical study with 100 participants (age 20 to 77) at a research hospital in Nagpur, India. Study subjects were stratified by age and divided into three groups corresponding to the disease severity: CAD, hypertensive ('Pre-CAD'), and Healthy.Main results. PWV measurements derived from the Ear-Toe probe measurements yielded the best performance, with median PWV values increasing monotonically as a function of disease severity and age, as follows: 14.2 m s-1for the older-patient CAD group, 12.2 m s-1for the younger-patient CAD group, 11.6 m s-1for the older-patient Pre-CAD group, 10.2 m s-1for the younger-patient Pre-CAD group, 9.7 m s-1for the older healthy controls, and 8.4 m s-1for the younger healthy controls. Using just two simple features, the PTT and patient height, we demonstrate a machine learning prediction model for CAD with a median accuracy of 0.83 (AUC).Significance. This work demonstrates the ability to predict atherosclerosis and CAD using a single simple physiological measurement with a multi-site PPG tool that is electrically powered by a mobile phone and does not require any electrocardiogram reference. Furthermore, this method only requires a single anthropometric measurement, which is the patient's height.

Comparison of cardiac output estimates by echocardiography and bioreactance at rest and peak dobutamine stress test in heart failure patients with preserved ejection fraction.

PURPOSE: To assess the agreement between cardiac output estimated by two-dimensional echocardiography and bioreactance methods at rest and during dobutamine stress test in heart failure patients with preserved left ventricular ejection fraction (HFpEF). METHODS: Hemodynamic measurements were assessed in 20 stable HFpEF patients (12 females; aged 61 ± 7 years) using echocardiography and bioreactance methods during rest and dobutamine stress test at increment dosages of 5, 10, 15, and 20 µg/kg/min until maximal dose was achieved or symptoms and sign occurred, that is, chest pain, abnormal blood pressure elevation, breathlessness, ischemic changes, or arrhythmia. RESULTS: Resting cardiac output and cardiac index estimated by bioreactance and echocardiography were not significantly different. At peak dobutamine stress test, cardiac output and cardiac index estimated by echocardiography and bioreactance were significantly different (7.06 ± 1.43 vs 5.71 ± 1.59 L/min, P < .01; and 4.27 ± 0.67 vs 3.43 ± 0.87 L/m2 /min; P < .01) due to the significant differences in stroke volume. There was a strong positive relationship between cardiac outputs obtained by the two methods at peak dobutamine stress (r = .79, P < .01). The mean difference (lower and upper limits of agreement) between bioreactance and echocardiography cardiac outputs at rest and peak dobutamine stress was -0.45 (1.71 to -2.62) L/min and -1.35 (0.60 to -3.31) L/min, respectively. CONCLUSION: Bioreactance and echocardiography methods provide different cardiac output values at rest and during stress thus cannot be used interchangeably. Ability to continuously monitor key hemodynamic variables such as cardiac output, stroke volume, and heart rate is the major advantage of bioreactance method.

Low-Cost Mobile Device for Screening of Atherosclerosis and Coronary Arterial Disease.

In the context of global health, telemedicine, and low-resource settings, we present a non-invasive smart-phone based device that can be used to screen for atherosclerosis,which is the leading factor for ischemic heart attacks and strokes. Using acustom Android mobile application, our device computes Pulse Wave Velocity(PWV) using the pulse signals from photo-plethysmographic (PPG) probes, which are simultaneously clipped onto the ear, index finger, and big toe of a human subject. Unlike other designs which require the use of an ECG reference, our mobile device uses only PPG signals and is entirely powered by the mobile phone via the USB port. Using the ear signal as a reference, we derived PWV values from two locations: the right index finger, and the right big toe.We present data from a recent clinical study with 78 participants (age 26 to 74) who were divided into three groups: Coronary Arterial Disease ("CAD"), hypertensive group ("PreCAD"), and Healthy controls. The CAD group was clinically diagnosed and confirmed with a CT-scan and calcium scoring. PWV values derived from the finger was found to have too much variance to be clinically useful. However, PWV values derived from the toe location showed significant differences between the groups, even after accounting for age. Measured PWV values were: 10.07 (8.51-12.01) for the older CAD group, 9.39 (7.44-9.75) for the younger CAD group, 8.26 (7.26-9.22) for the older Pre-CAD group, 10.57 m/s (8.5-11.2) for the younger Pre-CAD group, 7.13 m/s (5.97-7.69) for older healthy controls, and 6.71 m/s (4.86-7.26) for the younger healthy control subjects. These results demonstrate good potential value of this mobile PWV device as a simple low-cost screening tool for atherosclerosis and coronary arterial disease.

Myocardial fatigue in recreational marathon runners: A speckle-tracking echocardiography study.

BACKGROUND: Prolonged aerobic exercise such as marathon running produces supraphysiological hemodynamic stress that can potentially affect the athlete's cardiac homeostasis. While cardiac structural and functional adaptations in professional athletes are well characterized, only a limited information is available for recreational runners undergoing this supraphysiological stress. METHODS: Premarathon and post-marathon echocardiography was performed in 50 recreational marathon runners [age 40.8 ± 7.5 years, 44 (88%) males; running distance 42.195 km]. All the runners received 4-month training for the marathon. The baseline echocardiogram and N-terminal B-type natriuretic peptide (NT-proBNP) were obtained before training, whereas the post-marathon study was performed within 10 days (7.27 ± 0.92 days) of completion of marathon. Two-dimensional speckle-tracking echocardiography was used for characterizing the changes in myocardial mechanics. RESULTS: There was a significant reduction in heart rate post-marathon, whereas the levels of NT-proBNP increased significantly (86.0 ± 9.5 pg/ml vs 106.5 ± 24.2 pg/ml, p = 0.001). The left ventricular (LV) end-diastolic volume (61.8 ± 16.5 ml vs 72.8 ± 5.1 ml, p < 0.001), LV mass (120.2 ± 30.0 gm vs 160.3 ± 43.0 gm, p < 0.001), and LV ejection fraction (64.9 ± 5.6% vs 72.0 ± 5.7%, p < 0.001) also increased significantly. However, there was a significant attenuation in LV global longitudinal (-19.3 ± 2.71% vs -16.5 ± 4.6%, p = 0.003) and circumferential strain (-17.2 ± 2.41% vs -15.2 ± 2.6%, p = 0.001) post-marathon. The LV global radial strain showed a nonsignificant reduction. CONCLUSION: Recreational marathon runners have reduced longitudinal and circumferential shortening of the left ventricle with elevation of NT-proBNP. However, the LV ejection performance remains maintained because of an increase in the LV end-diastolic volume and mass. These changes suggest the possibility of "myocardial fatigue" occurring in response to supraphysiological hemodynamic stress of marathon running.

Inverted Takotsubo cardiomyopathy after attempted suicidal hanging--two cases.

We report two cases of "Inverted Takotsubo cardiomyopathy" following attempted suicidal hanging. Both the patients presented with heart failure and had desaturation 8-12h after the suicidal attempt. Electrocardiography (ECG) showed ischemic changes. On echocardiography, the left ventricle (LV) showed ballooning and hypokinesia of the basal segments with apical sparing. Both patients underwent coronary angiograms considering the possibility of acute coronary syndrome. However, their coronary angiograms were normal. After 3-4 days of hospitalization, both recovered; their ECG had reversed and the LV contractility was normal on echocardiography.