Impact of capacity building and tele ECG based decision support on change in thrombolysis rate and inhospital and one year mortality in patients with STEMI, using hub and spoke model; multi-phasic intervention trial.

BACKGROUND: We report the impact of capacity building and teleconsultation on change in the thrombolysis rates and one-year mortality in patients with STEMI using a hub and the spoke model of STEMI care. METHODS: Twenty secondary care public hospitals were linked with a teaching hospital as a hub centre and the impact of the intervention on change in ischemic time, thrombolysis rates and all-cause in-hospital and one-year mortality was compared. RESULTS: 29 patients with STEMI were treated during pre-intervention from April 2020 to June 2020 and 255 patients during the post-intervention period from July 2020 to Oct 2021 in spoke centres. 245 patients were reported to a hub centre during the study period. The thrombolysis rate was significantly higher in the spoke centres after intervention (65.5%vs. 27.5 % p < 0.001) and was also significantly higher than in patients treated in a hub centre (65.5 % vs. 45.7 % p < 0.01). The in-hospital mortality was significantly lower in patients treated at spoke centres compared to those treated at the hub centre (7.8 % vs. 15.5 % < 0.003). The significant difference in mortality rate continued at one year (11.0 % vs.18.4 % p < 0.01). The median time from symptoms to thrombolytic therapy was significantly lower in STEMI patients treated in spoke centres compared to a hub centre (230 min vs. 356 min p < 0.001). CONCLUSION: The hub and spoke model of STEMI care is effective in increasing thrombolysis rate, and decreasing in-hospital and one-year mortality rate.

Incidence, determinants, and outcomes of recovered left ventricular ejection fraction (LVEF) in patients with non-ischemic systolic heart failure; a hospital-based cohort study.

BACKGROUND: The data on incidence of recovered Left Ventricular Ejection Fraction (LVEF) and outcome in patients with non ischemic systolic heart failure is limited. We report the incidence, determinants and mortality in patients with recovered LVEF. METHODS: The 369 patients with HFrEF with LVEF of less than 40% of non ischemic etiology with available follow up echocardiography study at one year were enrolled. The baseline data of clinical characteristics and treatment was recorded prospectively and were followed up annually for mean of 3.6 years (range 2 to 5 years) to record all cause death and LVEF measured echocardiographically. The recovered, partially recovered and no recovery of LVEF was defined based on increase in LVEF to 50% and more, 41% to 49% and to persistently depressed LVEF to 40% or lower respectively. RESULTS: The LVEF recovered in 36.5%% of the cohort at 5 years. The rate of recovery of LVEF was slower in patients with no recovery of LVEF at one year compared to cohort with partially recovered LVEF (18% vs.53%) at five year. The Baseline LVEF was significantly associated with recovered LVEF, odd ratio (95% C.I.) 1.09(1.04, 1.14). The cumulative mortality at five years was significantly lower in cohort with recovered LVEF (18.1% vs. 57.1%). CONCLUSIONS: One third of the patients had recovered LVEF and was significantly associated with baseline LVEF and lower mortality rate.

Clinical characteristics, etiological profile, treatment and long term outcomes in patients with non ischemic systolic heart failure; Himachal Pradesh heart failure registry (HP-HF registry).

BACKGROUND: The data on clinical characteristics, treatment practices and out comes in patients with Non- ischemic Systolic Heart Failure (NISHF) is limited. We report clinical characteristics, treatment and outcomes in patients with NISHF. METHODS: 1004 patients with NISHF were prospectively enrolled and their demographics, clinical characteristics, and treatment were recorded systematically. Patients were followed annually for a median of 3 years (1 year to 8 years) for allcause death, major adverse cardiovascular events (MACE); composite of all-cause death, hospitalization of heart failure, and or for stroke. RESULTS: Patients of NISHF were middle-aged (58.8±16.2 years) population with severely depressed left ventricular ejection fraction (29.3±7.02%) and 31.1% had symptoms of advanced Heart failure. Hypertension (43.6%), obesity and or overweight (28.0%), Diabetes (15.0%), and valvular heart disease (11.8%) were the common risk factors. The guideline directed medical treatment was prescribed in more than 80% of the study cohort. Incidence of all cause death and MACE was 7 (6.8, 8.8) per 100 person years and 11(10, 13) per 100 person years respectively. The cumulative incidence of deaths and MACE was 35% (30%, 40%) and 49% (44%, 53%) at 8 years of follow-up. CONCLUSIONS: Patients of NISHF were middle-aged population with severely depressed LV systolic function with significant incident morbidity and mortality. Early detection of risk factors and their risk management and enhancing the use of guideline directed treatment may improve the outcomes.

Prevalence of rheumatic fever and rheumatic heart disease in rural population of Himachal--a population based study.

PURPOSE OF STUDY: Rheumatic heart disease is still the commonest valvular heart disease in India. There is no population based study regarding the prevalence of rheumatic fever/rheumatic heart disease (RF/RHD) from Himachal and hence the purpose of study. METHODS AND RESULTS: A community based survey for prevalence of RF/RHD was done in four villages of different districts of Himachal. The subjects suspected to have RF/RHD on clinical ground were subjected to echocardiography to confirm the diagnosis. Total 1882 subjects were screened. 909 were male and 973 were female. 11 of these were found to have RF/RHD (5.8/1000). Mean age of these patients was 30.35 +/- 14.17 years. 10 of these were female and one was male. Mitral valve was the commonest to be involved. Seven were known to have RF/ RHD and five were on penicillin prophylaxis. CONCLUSION: RF/RHD is still common in rural population of Himachal. Mitral valve is commonest to be involved and prevalence is much more in female than in male.

Epidemiological study of hypertension in natives of Spiti Valley in Himalayas and impact of hypobaric hypoxemia; a cross-sectional study.

Hypertension is the result of interaction between genetic vulnerability and exposure to unhealthy lifestyle. However, studies investigating the impact of cardiovascular adaptive response to hypobaric hypoxia and extreme cold in natives of high altitude on the development of hypertension have yielded conflicting results. A community based cross-sectional study was carried out in an unique population of Spiti valley of Greater Himalayas residing at an altitude of 3100-3500 m (group 1) and 3500 m and above (group 2) to evaluate the impact of altitude of residence on prevalence of hypertension. 413 subjects, age 20 years and above were selected by stratified cluster random sampling technique and screened for recording socio-demographic profile, anthropometrics, fasting blood sugar and blood pressure. There was no significant difference in the mean age (40.1 vs.38.0 years) and gender distribution (65.7% vs. 61.4% females) between the two groups. The overall prevalence of hypertension was 22.5% and achieved higher significance in group 1 (27.5%) compared to group 2 (19%); p < 0.041. The socioeconomic profile and lifestyle of group from higher altitude was significantly different with people being less educated, agriculture as main occupation compared to the group at lower altitude. On comparison, the same group had a lower prevalence of obesity 17.4% vs. 35.9% (p < 0.000), Diabetes 0.4% vs. 4.1% (p < 0.03) and impaired fasting glucose 5% vs. 11.1% (p < 0.06). Obesity, age and altitude of residence were significantly associated as independent predictors of prevalence of hypertension in this study. Hypobaric hypoxia thus appears to have a protective effect from developing hypertension. The prevalence of hypertension in natives of Spiti valley is thus influenced by lifestyle related risk factors, age and possibly altitude of residence.

Long term outcomes in patients with RF/RHD: Eight-year follow-up of HP-RF/RHD (Himachal Pradesh Rheumatic Fever/Rheumatic Heart Disease) registry in a Northern Indian state.

BACKGROUND: The long-term outcome data in patients with rheumatic fever/rheumatic heart disease (RF/RHD) is limited. We report the cumulative incidence of adverse outcomes in a cohort of RHD patients from a northern state of India at a median follow-up of 5.4 years. METHODS: 1714 patients with RF/RHD diagnosed using clinical and echocardiographic criteria were registered from 2011 to 2018, and their baseline clinical characteristics and treatment practices were recorded. Patients were followed up annually for a median of 5.4 years (range 1-8 years) for incident adverse outcomes. The cumulative incidence of adverse composite outcomes, all-cause mortality, hospitalization for heart failure, stroke, and/or peripheral embolism was estimated. The baseline clinical characteristics were explored to identify the potential risk predictors using a multivariate cox proportional hazard model. RESULTS: The cumulative incidence of adverse composite outcomes was 17.1% (15.3%-19.0%) at a median follow-up of 5.4 years. The predictors for the adverse composite outcomes (hazard ratio, 95% confidence interval) were age (1.03, 1.02-1.04), education status below primary level (1.60, 1.23-2.05), severe valvular heart disease (1.74, 1.36-2.23), NYHA class III/IV at enrollment (1.56, 1.18-2.07), right heart failure (4.48, 2.85-6.95), history of stroke and/or peripheral embolism (3.7, 1.5-9.2) and mitral balloon valvuloplasty (0.62, 0.40-0.96). CONCLUSIONS: The incidence of adverse outcomes is substantial in patients with RF/RHD. Thus, early detection of high-risk patients and their risk management is needed to improve outcomes.

Gender differences in the epidemiology of Rheumatic Fever/Rheumatic heart disease (RF/RHD) patient population of hill state of northern India; 9 years prospective hospital based, HP-RHD registry.

OBJECTIVES: We report the gender-based differences in the prevalence, severity, pattern of valvular involvement, and complications in patients with Rheumatic Fever/Rheumatic heart disease (RF/RHD). METHODS: The 2475 consecutive patients with RF/RHD diagnosed using clinical and echocardiographic criteria were registered prospectively from January 2011 till December 2019. The association of gender with the pattern of valvular involvement, nature, and severity of valvular dysfunction and cardiovascular complications was analyzed using a logistic regression model, and odds ratios with 95% CI were estimated. RESULTS: The mitral and tricuspid valve involvement was significantly lower in the male gender, odds ratio with 95% CI of 0.55 (0.44-0.61), and 0.69 (0.58-0.83) respectively, while the aortic valve was affected more frequently than females, odds ratio 1.36 (1.14-1.62). The severity of valvular disease had no significant association with gender, 0.99 (0.82-1.20). The association between gender and cardiovascular complications, heart failure, stroke, and atrial fibrillations were not statistically significant. The prevalence of RF/RHD was more than two-fold higher in female gender than male (71.4% vs. 29.6%, p < 0.0001). CONCLUSIONS: RF/RHD is more prevalent in females. Gender has a significant association with the pattern of valvular involvement. The severity of valvular dysfunction and cardiovascular complications had no significant association with gender.

Coronary heart disease in rural population of Himachal--a population based study.

BACKGROUND: Cardiovascular disease has emerged as a major health burden worldwide. There is no study in Himachal about the prevalence of coronary heart disease (CHD), hence the purpose of the study. MATERIAL AND METHODS: Population based study was done in three different villages of different districts of Himachal Pradesh. The people were well notified about the survey in advance. We tried to cover all persons above the age of 30 years. We could cover around 70% of population. Total 812 persons were examined. History regarding presence and nature of chest pain was taken. Detailed physical examination was done. The detailed history about risk factors was taken. ECG of all patients was taken. Patients known to have suffered myocardial infarction, having typical angina on exertion or having undergone coronary angioplasty or coronary artery bypass surgery were labeled to have CHD. RESULTS: Eight hundred twelve patients were examined. Mean age was 47.44 +/- 12.2 yrs. Three hundred ninty-nine were males and 413 were females. Thirty three patients were found to have coronary heart disease, giving the prevalence of 4.06%. Twenty six of 399 males had CHD (6.9%) and 26 of 413 females had CHD (1.69%). Seventeen of these CHD patients were hypertensive, two were diabetic and 10 patients had family history of CHD. CONCLUSION: The prevalence of CHD was low in rural population of Himachal Pradesh, being around 4%, more in males than in females.

Acute renal artery embolisation: role of local catheter-based intra-arterial thrombolysis.

A 45-year-old man without previous comorbidity presented to us with acute onset right-sided flank pain for last 14 hours. His general physical and systemic examination was unremarkable, and there were no clinical signs of peritonitis. The ultrasonography did not reveal any evidence of nephrolithiasis or hydronephrosis. His contrast-enhanced CT scan revealed hypoattenuated areas of right kidney and evidence of right renal artery thrombosis. He was immediately shifted to cardiac catheterisation lab, and his renal angiography showed thrombotic occlusion of right renal artery. The bolus dose of streptokinase (250 000 IU) was given locally in renal artery by right judkins catheter followed by systemic infusion of streptokinase (100 000 IU/hour) for 24 hours. After that he was started on low molecular weight heparin. Repeat renal angiography done after 5 days showed completely normal right renal artery. His cardiac and thrombophilia work up was negative, and he was discharged on antiplatelets, oral anticoagulants and statins.

Prevalence, risk determinants and consequences of atrial fibrillation in rheumatic heart disease: 6 years hospital based-Himachal Pradesh- Rheumatic Fever/Rheumatic Heart Disease (HP-RF/RHD) Registry.

OBJECTIVE: To report the prevalence, risk factors and consequences of atrial fibrillation (AF) in patients of rheumatic heart disease (RHD). METHODS: The Himachal Pradesh- Rheumatic Fever/Rheumatic Heart Disease (HP-RF/RHD) Registry database of 1918 patients was analyzed. AF was diagnosed with 12-lead ECG recording at entry in to the registry. The association of AF with nature and severity of valvular dysfunction was analyzed, adjusted for age, left atrial (LA) dimension and pulmonary arterial hypertension using multivariable logistic regression model and strength of association was reported as odds ratio (OR) with 95% confidence intervals (C. I.). RESULTS: The study population consisted of young (40.2 ±â€¯14.3 years), predominantly females (72.3%) from rural area (94.1%). Prevalence of AF was 23.9% (95% C. I. 22.1%-25.8%). The independent determinants AF were age (OR 1.04, 95% C.I. 1.03-1.06), LA size (OR 1.10, 95% C.I. 1.08-1.11). The association of AF with age, New York Heart Association functional class, mitral stenosis severity and tricuspid regurgitation was statistically significant and graded. Mitral regurgitation and aortic valve disease had no significant independent association with AF. The prevalence of heart failure, stroke, peripheral embolism and mortality was significantly higher among patients with AF (p < .01). CONCLUSION: AF is common in RHD patients and is significantly associated with heart failure and systemic thromboembolism. Age, mitral stenosis severity, tricuspid regurgitation and LA size were independently associated with AF.

Prevalence, risk factors, and significance of iron deficiency and anemia in nonischemic heart failure patients with reduced ejection fraction from a Himachal Pradesh heart failure registry.

BACKGROUND: The study aimed to estimate the prevalence, risk determinants, and its clinical significance of iron deficiency and anemia in patients of nonischemic heart failure with reduced ejection fraction (HFrEF). METHODS: Serum ferritin, transferrin saturation, and the hemoglobin (Hb) levels were measured in 226 consecutive patients with HFrEF diagnosed based on the left ventricular ejection fraction ≤ 45% and absence of coronary artery luminal narrowing of more than 50%, in a prospective tertiary care hospital-based heart failure registry. Patients with the New York Heart Association functional class III/IV were classified as patients with advanced heart failure. Multivariable logistic regression modeling was performed to assess the risk determinants of iron deficiency and anemia and their clinical significance as the risk factors for advanced heart failure. Odds ratio with 95% confidence interval (CI) was reported as the estimates of the strength of association between exposure and outcome variables. RESULTS: Iron deficiency and anemia were prevalent in 58.8% (52.2%-65.1%) and 35.8% (29.8%-42.3%) of patients, respectively. Female gender [OR 3.5 (95% CI 1.9-6.5)], history of bleeding [OR 11.7 (95% CI 1.4-101.2)], and vegetarian diet [OR 2.5 (95% CI 1.4-4.6)] were significantly associated with iron deficiency, while diabetes [OR 3.0 (95% CI 1.40-6.5)], estimated glomerular filtration rate [OR 0.98 (95% CI 0.97-0.99)], history of bleeding [OR 13.0 (95% CI 2.3-70.9)], and female gender [OR 2.9 (95% CI 1.5-5.7)] had significant association with anemia. The Hb level (OR 0.82 (95% CI 0.70-0.96) and transferrin saturation (OR 0.98 (95% CI 0.96-0.99)] had a significant inverse association with symptoms of advanced heart failure. CONCLUSION: Iron deficiency and anemia are common comorbidities associated with HFrEF. Low Hb and transferrin saturation are significantly associated with advanced heart failure. The findings have important implications in the management of heart failure.

Clinical Characteristics, Complications, and Treatment Practices in Patients With RHD: 6-Year Results From HP-RHD Registry.

BACKGROUND: Despite the high prevalence of rheumatic heart disease (RHD) in developing countries such as India, data on characteristics, complications, and treatment practices are lacking. The HP-RHD (Himachal Pradesh Rheumatic Heart Disease) registry aimed at reporting these parameters in patients with RHD from a northern state of India. METHODS: A total of 2,005 consecutive patients of RHD were enrolled over a period of 6 years (2011 to 2016) in the present study. The clinical characteristics, complications, and treatment practices were systematically recorded. RESULTS: The mean age for patients with RHD was 40.3 ± 14.3 (range 5 to 83 years). RHD predominantly affected females (72.3%) and population from rural background (92%). Multivalvular involvement was frequent (43.2%), mitral valve was the commonest affected valve (83.3%). The majority of the patients had moderate-to-severe valvular dysfunction (69.3%). Mitral and tricuspid valve involvement was more frequent in female subjects compared with more frequent aortic valve involvement in male subjects (p < 0.001). The major adverse cardiovascular events were recorded in 23.4% patients at the time of registry and comprised mainly advanced heart failure (15.6%), peripheral embolism (4.1%), and stroke (3.9%). The independent risk determinants of major adverse cardiovascular events (were advanced age (odds ratio [OR]: 1.01; 95% confidence interval [CI]: 1.00-1.02), severe mitral stenosis (OR: 1.73; 95% CI: 1.34-2.20), severe tricuspid regurgitation (OR: 2.11; 95% CI: 1.48-3.02), presence of pulmonary artery hypertension (OR: 1.33; 95% CI: 1.04-1.69), and atrial fibrillation (OR: 1.64; 95% CI: 1.28-2.11). Evidence-based use of oral anticoagulant therapy was documented in 77.7% of high-risk patients. Only 28.5% of study population was receiving secondary prophylaxis. CONCLUSIONS: Complications in patients with RHD increase with age and worsening valvular dysfunction. Programs focused on early detection and evidence-based management will assist in improving outcomes.

Takayasu arteritis presenting with total occlusion of the left main coronary artery ostium: an extremely rare occurrence.

A young 18-year-old female patient with exertional angina and claudication of the upper limbs was subjected to angiography. Bruits were auscultated over the bilateral renal arteries, right subclavian and right common carotid arteries. There was asymmetry of peripheral pulses. Laboratory parameters demonstrated a high erythrocyte sedimentation rate and C reactive protein. An aortic angiogram revealed a typical picture of Takayasu arteritis with bilateral subclavian, common carotid and renal involvement. A coronary angiogram was performed which showed total occlusion of the left main coronary artery. There was retrograde filling of the left coronary artery on right coronary artery injection up to the ostium of the left main coronary artery. Since the markers for disease activity were high, the patient was started on steroids and urgent coronary artery bypass grafting was planned. Unfortunately, the patient refused urgent intervention and was later lost to follow-up. This case describes an extremely rare occurrence of total occlusion of the left main coronary artery ostium in a patient with Takayasu arteritis.

A Constellation of Cardiac Anomalies: Beyond Shone's Complex.

Shone's anomaly is a very rare congenital cardiac malformation characterized by four serial obstructive lesions of the left side of the heart (i) Supravalvular mitral membrane (ii) parachute mitral valve (iii) muscular or membranous subaortic stenosis and (iv) coarctation of aorta. We report a unique presentation of Shone's complex in a 14-year-old adolescent male. In addition to the four characteristic lesions the patient had bicuspid aortic valve, aneurysm of sinus of valsalva, patent ductus arteriosus, ventricular septal defect, persistent left superior vena cava opening into coronary sinus and severe pulmonary artery hypertension. This case report highlights the importance of a strong clinical suspicion of the coexistence of multiple congenital cardiac anomalies in Shone's complex and the significance of a careful comprehensive echocardiography.

Prevalence of congenital heart disease in rural population of Himachal - A population-based study.

AIM: There is no community-based study about the prevalence of congenital heart disease (CHD) in Himachal; hence, we undertook this study. METHODS AND RESULTS: A population-based survey was done in four villages of different districts of Himachal Pradesh. In total, 1882 persons were examined. 909 were male and 973 were female. There were 12 cases of CHD in the population (6.3/1000): four of these were male (33.3%) and 8 were female (66.6%). Mean age of these patients was 19.5±11.07 years. Atrial septal defect (ASD) was the commonest lesion followed by ventricular septal defect (VSD). CONCLUSION: Prevalence of CHD in general population was 6.3/1000. ASD was the commonest lesion. CHD was more common in female.

Myocardial infarction in young adults-risk factors and pattern of coronary artery involvement.

BACKGROUND: Coronary artery disease (CAD) mostly occurs in persons older than 45 years of age. In India, CAD manifests almost a decade earlier than in Western countries. This study was done to study the risk factors and angiographic profile in young patients presenting with acute myocardial infarction (AMI). PATIENTS AND METHODS: One hundred and twenty four consecutive patients presenting with AMI at less than 40 years of age were studied for risk factors. Coronary angiography was done in all. RESULTS: Out of 124 patients, 123 were male. Mean age was 35.94 ± yrs. One hundred and eighteen had ST elevation myocardial infarction (MI) (95.16%) and six had non ST elevation MI (5.84%). Anterior wall MI was present in 88 patients (70.97%), inferior wall MI in 31 patients (25%) and lateral wall MI in five patients (4.03%). Seventy three patients (58.8%) were smoker, 55 were hypertensive (44.35%), 10 were diabetic (8.06%). Family history of CAD was present in 22 (17.7%) patients. Low High-density lipoprotein (HDL) was seen in 53 patients (42.7%), and high triglycerides in 60 patients (48.38%). Significant CAD was found in 88 (70.96%) patients, 13 (10.48%) had normal coronaries. Single vessel disease was seen in 57 patients, two-vessel disease in 15 patients and three-vessel disease in eight patients. Total 125 lesions were seen and left anterior descending (LAD) was the commonest vessel involved, with 78 lesions (62.4%). CONCLUSION: AMI in young almost exclusively occurs in male, and ST elevation MI is the main presentation. Anterior wall MI is most common, with LAD being involved in around 2/3 patients. Smoking, hypertension, low HDL and high triglycerides are the major risk factors.

Prevalence of high altitude pulmonary hypertension among the natives of Spiti Valley--a high altitude region in Himachal Pradesh, India.

The study aimed to determine the prevalence of high altitude pulmonary hypertension (HAPH) and its predisposing factors among natives of Spiti Valley. A cross-sectional survey study was done on the permanent natives of Spiti Valley residing at an altitude of 3000 m to 4200 m. Demographic characteristics, health behavior, anthropometrics, and blood pressure were recorded. Investigations included recording of 12 lead electrocardiogram (ECG), SaO2 with pulse oximeter, spirometry and echocardiography study, and measurement of Hb levels using the cynmethhemoglobin method. HAPH was diagnosed using criteria; tricuspid regurgitation (TR) gradient of ≥46 mmHg. ECG evidence of RV overload on 12 lead ECG was documented based on presence of 2 out of 3 criteria; R>S in V1, right axis deviation or RV strain, T wave inversion in V1 and V2. Data of 1087 subjects were analyzed who were free of cardiorespiratory diseases to determine the prevalence of HAPH and its predisposing factors. HAPH was recorded in 3.23% (95% C.I. of 0.9-8.1%) and ECG evidence of right ventricular (RV) overload was 1.5% in the study population. Prevalence of HAPH was not different in men and women 2.63% vs. 3.54% p<0.2. Age (Z statistics of 3.4 p<0.0006), hypoxemia (Z statistics of 2.9 p<0.002), and erythrocythemia (Z statistics of 4.7 p<0.003) were independently associated with HAPH. Altitude of residence was not found to be significantly associated with HAPH, although there was a trend of increasing prevalence with increasing altitude. It can be concluded that HAPH is prevalent in 3.23% of natives of Spiti Valley. Increasing age, erythrocythemia and hypoxemia are independent predisposing factors.

Epidemiological study of chronic mountain sickness in natives of Spiti Valley in the Greater Himalayas.

AIMS: This study determined the prevalence of chronic mountain sickness (CMS) and its predisposing factors among natives of Spiti Valley in the northern state of Indian Himalayas. A cross-sectional survey study was conducted in natives of Spiti Valley aged ≥ 20 years residing at altitudes of 3000 to 4200 meters. CMS was diagnosed using Qinghai criteria. Demographics, behavioral characteristics, specified symptoms of CMS were recorded, including BP, anthropometrics, evidence of RHF, PAH, and severe cyanosis. ECG, echocardiography, PFT, and Sao2 were recorded, and Hb level was estimated with the cyanmethhemoglobin method. RESULTS: 694 subjects free of cardiorespiratory diseases were analyzed. Prevalence of CMS was 28.7%, (95% C.I. of 25.9%-32.8%) and was higher in women than in men (36.6% vs. 15.7%, p<0.001). Erythrocythemia and hypoxemia were recorded in 10.5% and 7.5%, respectively. Age, truncal obesity, female gender, altitude of residence, and physical activity index were independent predictors of CMS with z statistics of 4.2, 2.29, -3.7, 2.8, and -2.8, respectively, and were statistically significant p<0.001. 6.2% of the surveyed population had HAPH. CONCLUSION: 28.7% (95% C.I. of 25.9%-32.8%) of the natives of the Spiti Valley in the Indian Himalayas are affected with CMS. Higher prevalence of CMS amongst women needs further studies. Westernized lifestyle appears to have predisposition to CMS.