Screening of Ischemic Heart Disease based on PPG Signals using Machine Learning Techniques

The increasing rate of cardiac ailments has led to the rise in the scrutinization of ones cardiac health. The prevalent techniques for detecting heart diseases are costly and require expert supervision as well as modern equipment. Thus there is a need for an alternative low cost and easily available technique. Finger-tip photoplethysmography (PPG) signals can be used for identifying Ischemic Heart Disease (IHD). This technique of screening the disease will be very helpful to the inhabitants of remote, underdeveloped and unprivileged areas. Time-domain analysis of the signal was done for extracting different features. Segregation of diseased and healthy subjects was performed using Decision Trees, Discriminant Analysis, Logistic Regression, Support Vector Machine, KNN, and Boosted trees. Ten different performance metrics was studied using the confusion matrix. After analysis, the accuracy, sensitivity, specificity, and precision of 0.94, 0.95, 0.95 and 0.97 respectively was obtained using Boosted tress classifier. ROC and AUC were calculated to establish the robustness of the classification methods for determining IHD patients.

Estimation of echocardiogram parameters with the aid of impedance cardiography and artificial neural networks

The advent of cardiovascular diseases as a disease of mass catastrophy, in recent years is alarming. It is expected to spread as an epidemic by 2030. Present methods of determining the health of one's heart include doppler based echocardiogram, MDCT (Multi Detector Computed Tomography), among various other invasive and non-invasive hemodynamic monitoring techniques. These methods require expert supervision and costly clinical set-ups, and cannot be employed by a common individual to perform a self diagnosis of one's cardiac health, unassisted. In this work, the authors propose a novel methodology using impedance cardiography (ICG), for the determination of a person's cardio-vascular health. The recorded ICG signal helps in extraction of features which are used for estimating parameters for cardiac health monitoring. The proposed methodology with the aid of artificial neural network is able to determine Stroke Volume (SV), Left Ventricular End Systolic Volume (LVESV), Left Ventricular End Diastolic Volume (LVEDV), Left Ventricular Ejection Fraction (LVEF), Iso Volumetric Contraction Time (IVCT), Iso Volumetric Relaxation Time (IVRT), Left Ventricular Ejection Time (LVET), Total Systolic Time (TST), Total Diastolic Time (TDT), and Myocardial Performance Index (MPI), with error margins of ±8.9%, ±3.8%, ±1.4%, ±7.8%, ±16.0%, ±9.0%, ±9.7%, ±6.9%, ±6.2%, and ±0.9%, respectively. The proposed methodology could be used in screening of precursors to cardiac ailments, and to keep a check on the cardio-vascular health.

Stroke Volume, Ejection Fraction and Cardiac Health Monitoring using Impedance Cardiography

In recent years occurrence of cardiac ailments have seen an exponential rise. In view of this it is highly important to monitor one's cardiac health. Currently employed methods for cardiac health monitoring are costly, require expert supervision and are available only at central hospitals. In order to overcome these obstacles, we have proposed a novel, non-invasive, cardiac health monitoring mechanism based on Impedance Cardiography (ICG). In this work we have proposed a methodolgy for determination of stroke volume (SV), left ventricular ejection fraction (LVEF), left ventricular end systolic volume (LVESV), and iso-volumetric relaxation time (IVRT), based on ICG. The proposed models report $\mathrm{r}^{2}$ values of 0.86, 0.97, 0.99, and 0.96 for SV, LVESV, LVEF, and IVRT, respectively. The proposed methodology also provides us an insight into the use of ICG for cardiac health monitoring, and diagnosis of critical cardiac ailments.

Respiratory response to tobacco dust exposure among biddi binders: A follow up and bronchodilator study

INTORDUCTION

The tobacco dusts get air borne during biddi making and it is inhaled by the biddi binders, which affects their health.

RESULTS

In a follow-up study, 86 biddi binders (male, 41; female, 45) were studied at a gap of 2 years. A high respiratory morbidity was observed among males than females both in the initial and follow-up study. The main complaints such as cough, sputum, and breathlessness showed high prevalence rates in the follow-up study. The high prevalence rates of weakness, giddiness, chronic diarrhea, and dyspepsia were noted in most of the cases the above complaints showed higher rates in the follow-up study. Pulmonary function test (PFT) values in the follow-up study of male and female biddi binders showed lowered compared with the initial study of same gender. In male and female biddi binders, the lung volumes SVC, FVC, FEV1, and the flow rates FEF0.2-1.2 l, FEF25%-75%, FEF75%-85% were significantly lowered in the follow-up study compared with the initial study. Age-related decrement in PFT was observed in both the studies. In nonsmokers, smokers, and ex-smokers, the PFT values are lowered. The current smokers have the lowest values in both the studies. With the administration of the bronchodilator aerosol (salbutamol) in 63 biddi binders (male, 27; female, 36), the effect of bronchodilator aerosol on the PFT parameters showed significant changes as all PFT parameters showed positive bronchodilatation.

CONCLUSION

The pattern of bronchodilator response on PFT values of the biddi binders suggests that the obstructions in the airways are reversible in nature.

Pulmonary function status of Kolkata inhabitants of different economic class during rainy and winter seasons

The pulmonary function status of the Kolkata inhabitants was evaluated during rainy and winter seasons. The pulmonary function tests (PFT) of the 1st study was carried out in the months of July to August when the environment is pollution free and the 2nd study was carried out between November to January when the environment is polluted. In the 1st study a total of 162 (male-88, female-74) inhabitants were investigated and again they were repeated in same way in the 2nd study. To evaluate the respiratory function status, Slow Vital Capacity (SVC), Forced Vital Capacity (FVC) and Peak Expiratory Flow Rate (PEFR) were recorded. Forced expiratory volume in one second (FEV1), forced expiratory volume in 1 sec as the percentage of FVC (FEV1%), forced expiratory flow at 200mL-1200 mL, 25-75% and 75-85% were calculated from the same tracings. Males were having higher mean PFT values compared to females because of sex difference. In the 2nd study PFT values were significantly lower compared to 1st study. According to different durations of stay category the PFT values were significantly reduced in winter season. The regression lines showed decrement as the duration of stay on that area was increased and it was more in 2nd study compared to 1st study. In both studies the PFT values found higher in high economic class of people. Between the same economic class of people PFT values were significantly lower in winter season. Respiratory impairments were also found higher during winter and males were having more impairment compared to females. Respiratory impairments in both sexes were more in winter and low economic class of people had maximum respiratory impairments. In rainy season and winter season the respiratory impairments were less in non-smokers. Males had more respiratory function impairments compared to females.

Impact of angiographic & procedural factors on the treatment of ostial LAD or LC(x) disease

AIMS & OBJECTIVES

This study was designed to evaluate the impact of angiographic & procedural factors on MACE after DES deployment in ostial lesions of LAD & LC(x). PATIENTS, MATERIALS & METHODS: 65 patients with ostial disease of LAD or LC(x) underwent PCI using DES. In 56 patients the stent was placed perfectly at the ostium & in 9 patients the LMCA was covered as per protocol. Angiographically 48 patients had a bifurcation angle > 70 degrees whereas in 17 patients the angle was < 70 degrees. RESULT & ANALYSIS: Multivariate Regression Analysis was done. Mean age was 59 years & 77% were male patients. 69% were hypertensives & 52% diabetics. LAD was treated in 88%. 74% had bifurcation angle > 70 degrees. 26% presented with an angle < 70 degrees LMCA was covered during stent implantation in 12% of cases. Average follow up was 1.5 +/- 0.8 years. Overall MACE was 12%. Bifurcation angle > 70 degrees & use of Cypher stent remained significant in reduction of MACE (P < 0.05). Using Univariate analysis of 2 sample sets like cases with angle of separation > 70 degrees (n = 48) & with angle less than < 70 degrees (n = 17), it was found that covering LMCA was beneficial in cases with angle of separation < 70 degres (p-value and correlation coefficient nearer to statistical significance).

CONCLUSION

Angiographic factors like bifurcation angle is important to formulate the strategy of stenting procedure in the ostial disease of LAD or LC(x) even with DES.

Respiratory effect related to exposure of different concentrations of arsenic in drinking water in West Bengal, India

Arsenic toxicity due to drinking of arsenic contaminated water has been one of the worst environmental health hazards. High levels of arsenic have been reported in different natural water sources from West Bengal for more than two decades. Groundwater contamination by arsenic and its adverse effects on the health of a big population in nine districts of West Bengal have been reported. The problems found were mainly related to skin and respiratory, digestive, cardiovascular and nervous systems. The respiratory effects are largely confined to those who had the skin lesion. The present study was undertaken to evaluate the respiratory effects of exposure to different levels of arsenic in drinking water. The water samples were collected from different tube wells and wells in the study area. Analysis of arsenic was done by Atomic Absorption Spectrophotometer with hydride generation system. Based on the consumption of arsenic concentrations in drinking water the populations were divided into three categories, i.e., <=50 microg/L, >50 - <= 150 microg/L and >150 microg/L. Standard techniques of medical examination were applied to elicit signs and recorded in the pre-designed proforma. A written consent was taken from each subject for their voluntary participation in the study. 112 subjects were investigated. The respiratory effect was evaluated by measuring the pulmonary function test (PFT). Vital Capacity (VC) and Forced Vital Capacity (FVC) were measured by Spirovit-SP-10 (Schiller Health Care Pvt Ltd., Switzerland) and Peak Expiratory Flow Rate by Wrights Peak Flow Meter (Clement and Clarke, UK). The PFT values showed gradual decrement among the males following skin pigmentation, keratosis and arsenicosis. The respiratory function impairment among the male subjects found as restrictive type (26.41%), obstructive type (3.77%) and combined type (7.54%), whereas in females only the restrictive type of impairment (10.16%) was found. Restrictive type of impairments among the subjects increased as the concentration of arsenic in drinking water increased, in males 15.78%, 29.41% and 35.29% and in females 4.54%, 5.00% and 23.52% respectively. The pathophysiologic mechanism, by which ingested arsenic leads to impairments of lung function and increased respiratory symptoms, is yet to be understood and needs further investigation.

Thrombosuction with export aspiration catheter during PCI in acute MI

The angiographic demonstration of thrombus laden LAD in a ventilated young man with IABP (to combat cardiogenic shock) demanded thrombosuction. Following thrombosuction no significant lesion was visible that could have mandated PTCA-Stenting. Follow-up coronary angiography in this hyperhomocysteinaemic young subject after one and a half month revealed normal coronaries. Thrombosuction alone unaccompanied by any other additional intervention is infrequently reported.

Importance of ischaemic time as a predictor of LV systolic function in Indians

OBJECTIVE

Sucessful reperfusion therapy in AMI improves LV systolic function. Success in thrombolytic therapy is directly related to the ischaemic time. Our aim in the present study was to observe the importance of ischaemic time as a predictor of left ventricular systolic function in patients undergoing PPCI. In addition, the contribution of presentation delay in determining the ischaemic time in the Indian scenario was also observed.

MATERIALS & METHODS

The present pilot study was carried out on 48 Indian patients (Male-40) of STEMI (Killip class I & II) undergoing primary PCI in last 2 yrs. Suggestive chest pain, ECG evidence of STEMI coming within 12 hrs were the inclusion criteria. Patients coming after 12 hours without ongoing chest pain, Killip class III & IV, the patients who were thrombolysed outside and the patients with prior PCland/or CABG were excluded from the study. Cardiac echodoppler study was done in every patient during followup at one month.Every patient received pre and peri procedural abciximab infusion and thrombosuction was done in all before deployment of BMS during the transfemoral primary PCI.

RESULTS

Data analysis revealed mean age was 57.6 yrs, male preponderance (80%),diabetes (35%),hypertension (61%), Smoking (61%), average total ischaemic time 7.6 +/- 3.78 hours, average presentation delay 6.26 +/- 3.77 hrs, average door to balloon time 60 +/- 14 mins, SVD (69%), LAD involvement(60%). Multivariate regression analysis without considering any other factor showed predicted LV Systolic function one month post PPCI to be 74.08%. Mean LVEF: 58.2%. Most interesting observation is 0.63% reduction of predicted LVEF for each hour increment of ischaemic time. Also LAD occlusion is associated with 4.91% reduction of predicted LVEF compared to other vessel(s) involvement. All the 48 patients who underwent PPCI not only survived but also had good LV Systolic function one month post PPCI.

CONCLUSION

Ischaemic time is an important predictor of LV Systolic function even after PPCI. lncrease in ischaemic time by one hour reduces predicted LVEF by 0.63%.Presentation delay is mostly responsible for total ischaemic time in India.

Pulmonary function in aluminium smelter and surrounding community--a case study

The increase of industrial activities in the Angul-Talcher area, Orissa resulted in indiscriminate disposal of waste into the environment leading to the deterioration of the quality of the environment, which affects the health of the workers as well as the community people. Considering the magnitude of the problem, the pulmonary function study had been carried out in one of the largest aluminium producing plant of the country as well as surrounding community people. Aluminium is produced from oxides of alumina by Hall-Heroult smelting process. The electrolysis called as aluminium smelting is carried out in an electrolytic cell (pot) having anode, cathode and electrolyte. The aluminium is deposited in the cathode and the oxygen moves towards anode is released. The workers working at the captive power plant (CPP), which is necessary to meet the power demand of the smelter plant were also investigated. 180 smelter plants workers (non-smoker 129, smoker-51) of different sections and 37 captive power plant workers (non-smoker 29, smoker-8) had undergone pulmonary function tests. Besides these, 85 persons from the surrounding community (non-smoker-66, smoker-19) were also investigated. The workers were all male. Spirometric assessments of Vital Capacity (VC), Forced Vital Capacity (FVC), and Peak Expiratory Flow Rate (PEFR) were done by Spirovit-sp-10 (Schiller Health Care Ltd, Switzerland) and Wrights Peak flow meter (Clement and Clarke, UK). Different lung volumes like FEV1, FEV1%, and flow rates like FEF200-1200ml, FEF25-75% and FEF75-85% were calculated from the same tracings pulmonary function test (PFT) results of the workers according to different age groups, duration of exposures and smoking habits. The mean values of SVC, FVC and FEV1 of smelter plant workers were found higher compared to the community people but the values of captive power plant workers were very much close to the values of the community people. A gradual decrement of the PFT values was found as duration of exposure increased. Lung volumes and the flow rates were decreased as age increases but in some age groups that trend was not followed. It has been found that in each category of subjects, smokers have the higher mean pulmonary function values compared to the non-smokers. Except the community people in all other cases the different flow rates were found higher in nonsmokers compared to smokers. The restrictive, obstructive and combined restrictive and obstructive types of impairments among the subjects were noticed. The respiratory impairment among the workers as a whole was found higher in smelter plant workers (9.44%) followed by the captive power plant workers (5.40%) and the community people (2.35%). In smelter plant workers both the restrictive and obstructive impairments were found higher compared to captive power plant and the community people.

A study on blood eosinophil level and ventilatory pulmonary function of the workers exposed to storage grain dust

The workers engaged in storage grain handling are exposed to storage grain dust and suffer from different respiratory symptoms like, cough wheezing, chest tightness, eye and nasal irritations. It has been reported abroad and the present study results noted that the grain handlers have allergic symptoms like redness of eyes, itching, sneezing, skin rash, breathlessness and decrement of pulmonary function test values. According to their nature of job, the workers of storage grain godowns were divided into four categories i.e., load handling worker (LHW), ancillary, quality control and depot administration workers. The pulmonary function tests (PFT) and the differential count of leucocytes were carried out among the workers by standard technique. Decrement of pulmonary function test values was noted with the increment of blood eosinophil level.

The PFT results were presented according to the blood eosinophil level. The decrement of mean PFT values were noticed as the blood level of eosinophil gradually increased from, up to -4%, >4-10% and above 10%. The maximum numbers of workers in different job categories are belonged to >4 -10% of eosinophil level. The percentage figure of workers in different departments were LHW 48.38%, (n=45), ancillary 38.88%, (n=7), quality control 54.54% (n=6) and depot administration workers 47.05% (n=16) are belonged to that range. Among the total workers the higher figure was found >4-10% ranges 47.43% (n=74) workers. The allergic manifestations like redness, itchiness and watering of eyes, sneezing, cough, breathless etc. are reported. These workers have blood eosinophil level and low pulmonary function test values. The respiratory impairments among the workers are restrictive, obstructive and combined restrictive and obstructive type.

Height, weight and earnings among coalminers in India

This paper analyses earning/wage differentials by height among coalmine workers in India. Our findings suggest that workers of above average height earn 9-17% more than their shorter counterparts and 6-13% more than average reference height. The results suggest that long-term investments in health human capital might ensure increase of labour productivity and thereby earnings, particularly in underdeveloped economies.

Respiratory health status of the roadside school children at Kolkata

School students in metro cities are often exposed to vehicle exhausts as their schools are situated mostly on the high traffic roadside. Acute exposure to automobile exhaust is associated with increased respiratory symptoms and may decrease and impair lung function in children. The lung functioning performance of the city school children was compared with rural school children where there is no pollution and automobile exhausts. In Kolkata, two schools for boys (n = 210) and two schools for girls (n = 200) and in rural area one school for boys (n = 99) and the other school for girls (n = 95) were investigated. City schools are situated on the main roadside, nearer to the traffic junction. The detail histories about health status of children, if they have any subjective feelings of health related problems during the school hours or after returning from the school, and the family histories were taken by questionnaire method. The pulmonary function tests (PFT) were carried out by Spirometric method by Spirovit-Sp-10 and Wright's Peak flow meter. The mean PFT values of the students found in the normal range. Boys were having higher values compared to the girls in both city and rural schools. Lung volumes and flow rates were significantly higher in rural students. Symptomatic changes like breathlessness, cough and other problems (sneezing, eye irritation, running nose etc.) among city schoolboys found 13%, 7% and 15% and in girls found 12%, 6% and 7% respectively. In symoptomatic students, mean PFT values were significantly lowered compared to non-symptomatic. PFT values were presented in relation to age and height. It has been found that a number of city school students are having different types of respiratory symptoms. Long-term effect of exposure into such environment may develop lung functional impairments.

Pulmonary Function Abnormalities Associated with Exposure to Automobile Exhaust in a Diesel Bus Garage and Roads

In Kolkata city the road transports are maintained by private and Government organization. A major work force belonged to the State Transport Corporation (KSTC), Government of West-Bengal. The pollution caused by these vehicles affects the workers health and caused different types of respiratory problems. This study was undertaken to assess the pulmonary function status of these workers. City KSTC garage workers were investigated and categorically divided into two group: garage mechanics and the (2) those transporting the passengers (drivers and conductors). Vital capacity (VC), forced vital capacity (FVC) and peak expiratory flow rate (PEFR) were recorded by Spirovit-SP-10 (Schiller Ltd, Switzerland) and Wright's Peak Flow Meter (UK) on 236 workers. The different flow volumes, FEV(1), FEV(1%), and flow rates, FEF(02-121), FEF(25-75%), etc. were calculated. The administrative people had higher PFT than the other categories. Drivers and conductors have almost equal mean PFT values but mechanical workers had slightly higher. PFT values according to different age ranges and duration of exposure showed gradual decrement as age and duration of exposure increased. Non-smokers had higher lung volumes compared to smokers and ex-smokers. Restrictive, obstructive and combined types of impairments were noticed in 28.4%, 1.7% and 2.9%, respectively, workers. The restrictive impairment was found to be 30.4% in conductors; 28.9% in drivers, 27.9% in mechanics and 21.7% in administration people. Obstructive type of impairment was found to be 2.9% in both drivers and conductors. The effect of pollution by dust and fumes may be responsible for these pulmonary function impairments, restrictive impairments being greater.

Pulmonary function of different categories of chronic obstructive pulmonary diseases in railway workers of eastern India

Pulmonary function tests were done on 146 established chronic obstructive pulmonary disease (COPD) patients and 151 normal non-smoker and smoker subjects. These patients were assembled from Garden Reach Railway Hospital (Calcutta), West Bengal, India, 79 of which suffered from chronic bronchitis, 8 from chronic bronchitis with mild emphysema (who were included in the chronic bronchitis group), 38 from emphysema and 21 from asthma. In the normal subjects 75 were non-smokers and 76 smokers. All the subjects were in the age range of 16-60 years. The mean values obtained in COPD patients were compared with those of normal non-smokers and smokers in each group and amongst the different categories of COPD patients. All the pulmonary function tests (PFT) were measured by the standard spirometric technique, and the Peak Expiratory Flow Rate (PEFR) was studied by Wright's Peak Flow Meter. The values were expressed in body temperature at ambient pressure saturated with Water Vapour Pressure (BTPS). The PFT values significantly deteriorated in all categories of COPD patients as compared to normal non-smokers and smokers, but a few parameters showed exceptions. Significant deterioration was observed in emphysematous patients when compared to other categories of COPD patients. No definite trend of reduction of pulmonary function test values were found according to the years of suffering from the disease. A product moment correlation matrix showed a highly significant positive correlation between FVC and FEV1, in all four groups of patients. These two parameters also showed a strong positive relationship with FEF25-75%, FEF200-1200ml, FEF75-85%, MVVF and PEFR. The regression equations for some of the closely related variables of high correlation coefficient were calculated in COPD patients and presented.

Effect of jute dust exposure on ventilatory function and the pertinence of cough and smoking to the response

The ventilatory capacity of 32 men exposed to jute dust in the jute industry, was estimated at the beginning and end of shifts on the first day and last day of a working week. A detailed occupational, clinical and smoking history was recorded and a more detailed questionnaire on respiratory symptoms was completed prior to the pulmonary function tests. The presence of a productive cough among workers was noted. A mean decrease of forced expiratory volume at one second (FEV1) was observed among workers according to processes, concentration of dust exposure and smoking habit on the first day and last day of the week. The mean difference of values was observed in most of the comparisons but only a few were statistically significant. Low mean values of FEV1 were observed in workers having high dust exposure, a smoking history and productive cough in comparison to the low dust exposure group, non-smokers and workers without cough symptoms. The significant deterioration of FEV1 was found between before shift and after shift values of the low dust exposed group of workers who had a cough and smoking history. The relevance of these factors on the ventilatory function is observed and discussed.

Peak expiratory flow rate of jute mill workers in Calcutta

Ventilatory capacity of 32 control and 318 asymptomatic male jute mill workers of the Calcutta area, India was measured by Wright's Peak Flowmeter. Mean values of peak expiratory flow rate (PEFR) was 514 +/- 66.41 l/min in Control and 475 +/- 66.02 l/min and 462 +/- 67.42 l/min in exposed non-smoker and smoker workers respectively. The relationship of PEFR with age, height, duration of exposure and smoking habit were studied. Multiple regression techniques were used to determine the form of the relationship of age, height, exposure and smoking habit with PEFR. The findings have been compared with those of Indian and foreign authors. The possible reasons of difference includes smoking habit, occupational exposure, physical background and residence in polluted area etc.