|Year : 2019 | Volume
| Issue : 2 | Page : 67-73
Clinical presentation and outcome in patients presenting with acute coronary syndrome – A prospective study
Sivaramakrishna Battula1, V Satyanarayana1, D Rajasekhar2, A Krishna Simha Reddy1, Venkatesh Satri1
1 Department of Emergency Medicine, Sri Venkateswara Institute of Medical Sciences, Tirupati, Andhra Pradesh, India
2 Department of Cardiology, Sri Venkateswara Institute of Medical Sciences, Tirupati, Andhra Pradesh, India
|Date of Web Publication||11-Nov-2019|
Professor and Head, Department of Emergency Medicine, Sri Venkateswara Institute of Medical Sciences, Tirupati, Andhra Pradesh
Source of Support: None, Conflict of Interest: None
Background: Acute chest pain is one of the most common reasons for seeking care in the emergency department. Acute coronary syndrome (ACS) is a spectrum of diseases comprising unstable angina (UA), non-ST-segment elevation myocardial infarction (NSTEMI) and ST-segment elevation myocardial infarction (STEMI). The present study was undertaken to study the clinical presentation and outcomes of patients with ACS.
Methods: In this prospective observational study conducted in a tertiary care teaching hospital in Tirupati, during the period February 2015 to June 2016, demographic, clinical profile, treatment modalities and outcome in patients with ACS were studied.
Results: A total of 1034 patients with ACS presented to the emergency room, during the study period. Mean age of the study population was 56.7 ± 11.7 years. STEMI accounted for 67% of the cases. Three hundred and forty one patients (33%) presented with NSTEMI (n = 256) and UA (n = 85). In 823 patients with ACS (79.6%), percutaneous coronary intervention (PCI) with stenting was done, and among those, primary PCI was done in 196 cases. Mean duration of stay in the hospital was 4.86 ± 1.5 days. Thirty-seven cases (3.9%) expired during the follow-up period. Reinfarction in minority cases (0.8%).
Conclusions: In the present study, ACS is more common in the younger age group with male predominance. Majority of the patients presented with Killip Class I. Most of the patients underwent PCI.
Keywords: Acute coronary syndrome, clinical profile, percutaneous coronary intervention
|How to cite this article:|
Battula S, Satyanarayana V, Rajasekhar D, Simha Reddy A K, Satri V. Clinical presentation and outcome in patients presenting with acute coronary syndrome – A prospective study. J Clin Sci Res 2019;8:67-73
|How to cite this URL:|
Battula S, Satyanarayana V, Rajasekhar D, Simha Reddy A K, Satri V. Clinical presentation and outcome in patients presenting with acute coronary syndrome – A prospective study. J Clin Sci Res [serial online] 2019 [cited 2019 Dec 16];8:67-73. Available from: http://www.jcsr.co.in/text.asp?2019/8/2/67/270749
| Introduction|| |
By the year 2020, it is estimated that coronary artery disease (CAD) would rise in the developing nations by 120% in women and 137% in men. When compared to all the developing nations, India has been showing the most rapid epidemiologic transition from communicable to non-communicable diseases and is characterised by high burden of atherothrombotic dominated non-communicable diseases. CAD constitutes the largest contributor to cardiovascular disease burden in India. Rates of secondary CVD prevention are low in India and other developing countries.
It is estimated that by 2020, ischemic heart disease will result in 2.5 million number of deaths, whereas disability-adjusted life years lost due to CAD is expected to rise to about 7.67–14.4 million in men and 5.6–7.7 million in women in India. Acute coronary syndrome (ACS) quality improvement programmes have been employed in the USA, Sweden and China and among other countries. Published results of these programmes have demonstrated improvements in the inhospital and discharge process of care measures with associated improvements in outcomes.,,,
Compared to the western world, in India, CAD is characterised by premature occurrence in the young and in low- and middle-income group and with high mortality and high prevalence of diabetes mellitus (DM).,
In the present study, we prospectively studied the details regarding clinical presentation and outcome of patients presenting with ACS to the Emergency Medicine Service of Sri Venkateswara Institute of Medical Sciences (SVIMS), Tirupati over a period of 18 months. SVIMS has a comprehensive emergency room (ER) where cardiac, respiratory or any type of emergency can be managed. The Department of Cardiology is the first of its kind in the whole Rayalaseema area of Andhra Pradesh, which offers all the non-invasive, invasive and interventional facilities for all the cardiovascular problems. After stabilisation of patients in ER, the treatment strategies including drug treatment, percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG) as well as complications and outcomes were recorded by follow-up of patients till discharge and follow-up at 30 days.
| Material and Methods|| |
In a prospective observational study, we studied all patients with ACS presenting to the ER, SVIMS, Tirupati, between February 2015 and July 2016. The study was conducted after approval from the Thesis Protocol Approval Committee and the Institutional Ethics Committee. All the patients presented to ER with features suggestive of ACS [Table 1], who are willing to participate in the study were included in the study. Patients who were not willing to participate in the study, patients with ACS who have been initially treated elsewhere and referred to us for additional management and patients with ACS within 30 days of CABG or PCI were excluded from the study. Written informed consent was obtained from the patients for participation in the study. After receiving the patients in ER, all the patients were thoroughly evaluated which includes onset and duration of chest pain, breathlessness, associated symptoms such as sweating and palpitations. A detailed history regarding conventional cardiovascular risk factors including smoking, hypertension, diabetes and hyperlipidaemia and alcohol consumption was obtained. DM was diagnosed if a patient suffered from DM before ACS. The patient was assumed to be a tobacco smoker if he/she smoked tobacco before ACS. History of hypertension or usage of antihypertensive medication and/or blood pressure ≥140/90 was categorized as hypertension. Dyslipidaemia was defined according to the European Society of Cardiology prevention guidelines, with total cholesterol ≥190 mg/dL and/or triglycerides ≥150 mg/dL, or when the patient was on hypolipidaemic therapy with statins/fibrates before ACS. Details regarding clinical presentation, conventional risk factors and physical examination were recorded in a proforma. All patients were classified based on Killip classification. Killip classification was determined at the time of admission in the emergency department (ED). Specifically, Killip Class I patients were patients with no evidence of heart failure; Killip Class II patients had mild heart failure with rales involving one-third or less of the posterior lung fields and systolic blood pressure of 90 mmHg or higher; Killip Class III patients had pulmonary oedema with rales involving more than one-third of the posterior lung fields and systolic blood pressure of 90 mmHg or higher and Killip Class IV patients had cardiogenic shock with any rale and systolic blood pressure lower than 90 mmHg.
|Table 1: The American College of Cardiology Foundation/ American Heart Association updated guidelines for the diagnosis of acute coronary syndrome,|
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All patients underwent the following laboratory investigations: haemoglobin; total count; differential count; erythrocyte sedimentation rate; random blood sugar; blood urea; serum creatinine; serum electrolytes including sodium, potassium, calcium and cardiac enzyme markers, such as, troponin-I and creatine kinase-MB (CK-MB); chest X-ray; electrocardiogram (ECG); coronary angiogram (CAG) and two-dimensional echocardiogram (depending on patients clinical status and ECG findings) were done.
Data were recorded on a predesigned pro forma and managed using Microsoft Excel 2007 (Microsoft Corp, Redmond, WA). Descriptive statistical data were presented as mean ± standard deviation or median (interquartile range) for continuous variables and as percentages for categorical variables.
| Results|| |
A total of 1034 patients with ACS presented to the ER, SVIMS, Tirupati, between February 2015 and July 2016 were studied. Male preponderance was noted (n = 710; 68.8% of the overall cases). Male-to-female ratio was 2.2:1. Majority of the cases were from Rayalaseema region in southern Andhra Pradesh which includes four districts and the Nellore region adjoining the Chittoor district. Eighty eight percent of the study population are from the Chittoor and Kadapa districts.
Seven hundred and thirty three (71%) cases were referred to the study centre by the local physicians and the rest presented directly. Majority of the patients (n = 652) were shifted to the hospital using private transport means such as private ambulance, jeeps, rented cars and autos, and a few of them were carried in their own vehicles. Public transports such as buses were used by nearly 28.9% of the cases.
The “108” ambulance services provided transit facility to 8.1% of the cases. The most common presenting complaint was chest pain and diaphoresis, followed by breathlessness [Table 2], and majority of the patients presented in Killip Class 1. Other presenting symptoms along with chest pain are palpitations, nausea/vomiting and syncope. In a few cases (n = 21), patients complained of abdominal pain.
Mean heart rate of the study population was 78.6 ± 19.2 (beats/min), and systolic blood and diastolic blood pressures were 141.5 ± 29.1 and 85.4 ± 15.1 mmHg, respectively.
More number of ACS patients presented to ED in Killip Class 1 (75.2%) and Class 2 (14.9%) and very few were in Killip Class 3 (5.8%) and Class 4 (4.1%). Average duration from the onset of symptoms to the arrival to hospital in the present study was 9 hours.
The following risk factors were present: hypertension (53%) and tobacco smoking (46%) are the risk factors present in majority of patients followed by alcoholism and type 2 diabetes (27%). There was a family history of CAD (31%) and dyslipidaemias (16%). No identifiable risk factors were evident in 8%.
Among the patients with STEMI (n = 693), 64% of cases (n = 442 cases) had anterior wall MI, 123 (18%) had isolated inferior wall MI (IWMI), 70 (10%) of cases (n = 70) had IWMI + right ventricular MI and 58 cases (8%) had IWMI + posterior wall MI changes on ECG at the time of presentation to ER.
A total of 530 (51%) patients had left ventricular (LV) systolic dysfunction on 2D echo cardiography at the time of presentation to ER. Mild LV systolic dysfunction was seen in 333 (32%) patients, moderate LV systolic dysfunction in 114 (11%) and severe LV systolic dysfunction in 83 (8%) cases.
CAG was done in 872 patients. Single-vessel disease was the finding in majority of the patients (50%, n = 519), followed by double-vessel disease in 28% and triple-vessel disease in 6% of the cases. CAG was not performed in 16% (n = 192) of ACS patients.
In 823 (79.6%) patients with ACS, PCI with stenting was done, and among those, primary PCI was done in 196 cases [Figure 1]. Of the 693 cases with STEMI, primary PTCA was done in 196 (28%) of the STEMI cases. Patients in whom PCI was done other than primary PCI group include the patients with delayed presentation to the hospital and those patients where thrombolytic therapy was done in hospital and outside centres. Inhospital thrombolysis was done in 153 (14.8%) of the cases, and among those, 124 (12%) underwent PCI with stenting. Among the 41 patients who are advised CABG, 15 underwent the surgery at the study centre and 11 cases were operated at different centres.
|Figure 1: Treatment modality among acute coronary syndrome patients. PCI = Percutaneous coronary intervention, CABG = Coronary artery bypass grafting|
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Mean duration of stay in the hospital was 4.86 ± 1.5 days. Various complications occurred in our study population are shown in [Table 3].
Short-term outcomes of the patients with ACS were studied at the end of 1-month period. Of the total 1034 cases, 53 (51%)expired during the inhospital stay. Thirty-five cases were lost follow-up, so the outcomes were studied in the remaining 946 cases. Thirty-seven cases (3.9%) expired during the follow-up period. Reinfarction rate is seen in minority cases (0.8%). Congestive cardiac failure requiring readmission is seen in 2.6% of cases. Bleeding complications requiring the blood transfusion are not recorded in the study cases.
Comparison of dake from the present study with other studies shown in [Table 4].,,
| Discussion|| |
Epidemiological studies have revealed that the prevalence of CAD is increasing along with the rising prevalence of conventional risk factors for CAD in India. The present health transition from the predominance of infections to the preponderance of cardiovascular disorders, such as hypertension, diabetes and CAD, is now responsible for 53% of all deaths.,
In our study the mean age at presentation was similar (56.7 ± 11.7 years) to other studies from India,, but lower than that observed in western population.,
Hypertension and smoking were the risk factors present in majority of patients, followed by alcoholism, diabetes mellitus and dyslipidaemias. In 319 cases (31%), family history of CAD was present. Hypertension is a conventional risk factor implicated in CAD. In our study, 53% of the patients were hypertensive. The prevalence of hypertension in South Asian cohort of INTERHEART study (31.1%) was lower compared to our study but near to other Indian studies., The higher prevalence of diabetes mellitus and hypertension in this region could be explained by the comparatively higher development and increasing epidemic of CAD.
STEMI accounted for 693 (67%) of the cases. NSTEMI and unstable angina (UA) together constituted 341 (33%). STEMI was the most common ACS admission diagnosis and had the highest inhospital mortality and non-fatal event rates, compared with non-STEMI and UA. Inhospital medical therapy was relatively high overall for all groups, with anti-platelet therapy being the most common (98.1%). The use of key medical treatments (antiplatelet dugs, β-blockers, ACE inhibitors and lipid-lowering drugs) was similar to that in other registries.
Single-vessel involvement was the most prevalent in all groups of ACS including UA/NSTEMI and STEMI, followed by double and triple vessels, and is similar to that reported in other studies.,
The types of ACSs in our study differed from those recorded in developed countries.,, In contrast with data from developed countries, we recorded more cases of STEMI than non-STEMI or UA, longer delays before admission to hospital and between admission and reperfusion therapy and different practice patterns and outcomes.
We noted that 67% of patients had STEMI, whereas in reports from developed countries,,, fewer than 40% had STEMI. With a mean age of 54.7 years, participants in our study were younger than those in developed countries.,,
Patients in our study took a longer average time to reach hospital than times reported in other registries. Majority of the patients (n = 652 patients) were shifted to the hospital using private transport means such as private ambulance, jeeps, rented cars and autos, and a few of them were carried in their own vehicles. Public transport such as buses are used by 28.9% of the cases. The “108 ambulance” services provided transit facility to about 8.1% of the cases. Although a significant number of patients were transported to the primary care centre by 108 service, patients from distant places have to take other means to arrive at the tertiary centre. Few patients used an ambulance to reach the hospital; most of them used private or public transport. The reasons patients reached hospital late include economic reasons, a lack of awareness of the importance of the symptoms and delay at different types of healthcare providers that prevent rapid access to secondary and tertiary care hospitals., Lack of ambulance services, traffic congestion and long distances and consultation with local physicians also delayed patients. In hospital, it took further 50 min to undergo thrombolysis, compared with a range of 32–40 min in developed countries.,,,
We recorded major differences in practice patterns in our study compared with those from other Indian studies. In patients in our study, rates of primary PCI were higher than in other studies from India.,, In 823 cases (79.6%), PCI with stenting was done, and among those, primary PCI was done in 196 cases [Figure 1]. Patients in whom PCI was done other than primary PCI group include the patients with delayed presentation to the hospital and those patients where thrombolytic therapy was done in hospital and outside centres. Inhospital thrombolysis was done in 14.8% of the cases.
Medical management was opted in patients with significant renal dysfunction, patients of extreme age and in patients who are not willing to undergo CAG. CABG was advised in 41 cases (4% ) of the cases with triple-vessel disease and in those patients with significant left main CAD.
This might have been due to the state of art facilities available at the Department of Cardiology at our institute, first one of its kind in the whole Rayalaseema area of Andhra Pradesh, where the non-invasive, invasive and interventional facilities for all the cardiovascular problems are offered. This could have been the reason for the better reperfusion rates as compared to other Indian studies. Furthermore, the cashless healthcare benefit scheme, Dr. NTR Vaidya Seva Scheme implemented by the Andhra Pradesh State Government with a mission to provide quality healthcare to the poor, has helped in crossing the barriers regarding cost of treatment as nearly 76.7% of the study population were availed treatment under this government-funded scheme.
Mean duration of stay in the hospital was 4.9 ± 1.5 days. Of the 1034 cases, 53 died during the inhospital stay. Thirty-five cases were lost follow-up, so the outcomes were studied in the remaining 946 cases. Thirty-seven cases (3.9%) expired during the follow-up period. Reinfarction rate is seen in minority cases (0.8%). Congestive cardiac failure requiring readmission is seen in 2.6% of cases. Bleeding complications requiring the blood transfusion are not recorded in the study cases.
The mean age group of the patients presenting with ACS in the present study is similar to other Indian studies., STEMI is the most common among the ACS patients, followed by NSTEMI and UA. The (Kerala ACS registry), however, reported a delayed mean age of presentation with ACS, and in the same study, STEMI was only 37% among ACS patients.
In all the Indian studies, males outnumbered the females and are the majority group in ACS patients. Primary PCI in the present study is 28% among the STEMI patients. In the CREATE registry, primary PCI was performed in only 8% of the cases. This difference might be due to the advanced catheterization laboratory facilities available at the study centre. However, in the GRACE registry, the primary PCI rate was around 40% in STEMI patients [Table 4].
Complication rates are relatively low compared to other registries, as in our study, the death rate at 30 days was 3.9%, whereas in the CREATE study, the death rate reported was 6.7%, and a single-centre study from Guwahati Medical College from Northeastern India reported the death rate as 10.2%. Other complications such as reinfarction, stroke and bleeding requiring transfusion are low compared to the other study groups.
There are certain limitations of our study. This is a single-centre study, and pattern of ACS can be different in other parts of the country. Mortality rates in our study could be underestimated because we might have missed deaths before admission to hospital and some of the patients who missed the follow-up might have died. We have not taken details regarding factors such as detailed dietary habits, exercise frequency and body mass index. Medium and long-term outcomes of these patients are not studied. Patients who presented to ER were taken into consideration. Patients those admitted from the outpatient department and direct admissions were not taken into consideration.
Patients with ACS in India tend to be young compared to the western groups and to have a higher rate of STEMI than do patients in developed countries. Higher male preponderance is seen in the study group. Higher prevalence of hypertension and smoking is seen in the present study. Majority of the patients were in Killip Class I at presentation. Overall single-vessel disease is the most prevalent in ACS patients. The primary PCI rate is higher compared to other Indian studies. Strategies to reduce delays in access to hospital and early revascularisation therapy may reduce morbidity and mortality from ACS in India.
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Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3], [Table 4]