European Journal of Cardiovascular Medicine

STEMI results from the acute occlusion of a coronary artery, leading to myocardial ischemia and necrosis. While there have been significant improvements in both the diagnosis and treatment of STEMI, it continues to pose a serious public health issue in developed nations and is increasingly prevalent in developing countries. ^[1,2] There have been different stages of improvements in the care of patients with STEMI. Patients with untreated STEMI face higher mortality rates and poorer clinical outcomes than those who undergo reperfusion therapy. Timely reperfusion, achieved via thrombolysis or primary percutaneous coronary intervention (PCI), is essential for preserving myocardial tissue. ^[3] Although streptokinase has its limitations compared to newer thrombolytics, it remains widely used due to its cost-effectiveness. ^[2]

The American Heart Association (AHA) suggests that adequate and rapid use of available reperfusion therapy is more important than treatment selection. ^[4] Similarly, the European cardiology guideline recommends PCI only when it can be achieved within two hours. ^[5] The AHA also specifies that PCI should only be conducted when certain criteria, such as a door-to-balloon time of less than 90 minutes and appropriate skill levels, are met. ^[4] Randomized controlled trials (RCTs) have reported that initiating fibrinolytic early after symptom onset leads to a high reperfusion rate and improves mortality. ^[6,7] The potential for saving more lives exists if fibrinolytics can be administered during the prehospital phase or immediately upon arrival at the hospital, especially if given within one hour of symptom onset. ^[4]

When the ECG does not conclusively indicate STEMI, early assessment of wall motion abnormalities via echocardiography can guide treatment decisions regarding the need for reperfusion therapy. ^[4] Echocardiographic evaluation of left ventricular (LV) function is invaluable for prognosis; identifying reduced function may indicate the need for treatment with renin-angiotensin-aldosterone system inhibitors.4 Additionally, echocardiography can reveal right ventricular (RV) infarction, ventricular aneurysm, pericardial effusion, and left ventricular thrombus. ^[8] Doppler echocardiography is particularly useful for detecting and quantifying complications such as ventricular septal defects and mitral regurgitation, which can arise from STEMI. ^[8,9] 2D echocardiography serves as a non-invasive technique for evaluating LV function, wall motion abnormalities, and post-infarction complications. ^[9] This study aims to investigate the role of streptokinase in the management of STEMI and examine its effects on 2D echocardiographic parameters, ultimately seeking to correlate these findings with clinical outcomes.

The present study comprises of 50 cases of ST elevation myocardial infarction (STEMI) which were admitted in ICCU department during the period between April 2022 to September 2022.

Total 220 patients were thrombolysed with Streptokinase. This study included 50 patients on the basis of inclusion criteria mentioned subsequently.

These patients then were classified into different types of MI according to ECG changes. Following thrombolysis, these patients were run through series of ECGs, cardiac marker - CKMB and 2D ECHO. Routine blood Investigations including complete blood count, random blood sugar, serum creatinine, serum CKMB levels, lipid cholesterol and triglycerides were done.

Following these, an observational study of these 50 cases was done after prior informed consent.

Inclusion Criteria:

• Patients with 1st time diagnosed ST Elevation Myocardial Infarction irrespective of clinical symptoms
• Age > 20 years
• Patients who will be thrombolysed with Streptokinase

Exclusion Criteria:

• Patients with previous history of Ischemic Heart Disease
• ACS - Unstable Angina and NSTEMI
• Patients who had prior coronary reperfusion intervention

This clinical study involved 50 patients diagnosed with ST Elevation Myocardial Infarction (STEMI) who were treated with Streptokinase, and their 2D echocardiography findings were documented. Demographic and clinical characteristics were mentioned in table 1. Maximum no. of patients (76%) were included in age group from 40 to 70 years. Less patients (24%) were included in younger age group. Above the age of 70 the incidence of STEMI decreases i.e. 10 patients (20%). The most prevalent symptom was chest pain, reported by 88% of patients, followed by sweating (62%), breathlessness (36%), anxiety (32%), and 32% exhibited other symptoms such as palpitations, dizziness, vomiting, and nausea. Maximum patients (70%) presented within 12 hours a44%)nd 24 (48%) presented symptoms between 6 to 12 hours from the onset of symptoms. Among the total population, 12% had a history of type II diabetes mellitus, while only 6% had a history of hypertension. Smoking was identified as a major risk factor, affecting 30 patients (60%), and 11 patients (22%) reported alcohol addiction. On admission, 21 patients (42%) experienced tachycardia, and 2 patients (4%) had bradycardia, while 3 patients (6%) presented with cardiogenic shock.

Regarding myocardial infarction types, 28 patients (56%) had an anterior wall MI, including 12 with anteroseptal and 8 with anterolateral involvement mentioned in table 2. A total of 21 (42%) patients had inferior wall MI, Out of them 14 patients having isolated inferior wall MI, 3 having right wall combined with inferior wall MI, and only one having posterior wall involvement. One patient had isolated lateral wall MI. ECG findings at admission shows that 41(82%) patients had STEMI, 7(14%) patients had Q/QS with ST elevation changes and other 4% had other changes. ECG findings after 3 hours shows that 30(60%) patients had changes of successful reperfusion. Only 4(8%) patients had persistent ST-elevation after thrombolysis.

Baseline CKMB levels indicated that 37 patients (74%) had levels exceeding 100 on admission, increasing to 42 patients (84%) after 8 hours of thrombolysis. The elevation of CKMB levels post-thrombolysis suggests an early peak. In-hospital complications were documented in 11 patients (22%), with acute left ventricular failure (10%) being the most common, followed by cardiogenic shock (6%), arrhythmias (4%), and heart block (2%). Only 1 patient (2%) developed atrial fibrillation as a complication after reperfusion with Streptokinase. Patients 38(76%) had resolution of ST- segment elevation by 50% after thrombolysis with STK and 29(58%) patients had elevated CKMB levels after thrombolysis.

Severe left ventricular dysfunction was observed in 22 patients (44%), while 17 patients (34%) experienced moderate dysfunction post-STEMI (table 3). Hypokinesia was noted in 46 patients (92%), whereas 4 patients (8%) exhibited total akinesia regarding regional wall motion abnormalities.  Valvular dysfunction was found in 22 patients (44%) with mild mitral regurgitation (MR) and 14 patients (28%) with moderate MR; 4 patients showed no valvular dysfunction. The study found 6% in-hospital mortality rate.

Table: 1 Demographic and clinical characteristics

Table: 2 Type of myocardial infarction

*MI- myocardial infarction

Table 3: 2D echocardiographic parameters

 * RWMA- regional wall motion abnormality; † LVEF- left ventricular ejection fraction; ‡ MR-mitral regurgitation; § AR-aortic regurgitation

The current clinical study analysed 50 cases of ST Elevation Myocardial Infarction treated with thrombolysis using Streptokinase, along with their corresponding 2D echocardiographic findings. In the present study, there were 40 males (80%) and 10 females (20%), yielding a male-to-female ratio of 4:1, which is consistent with findings from both Thapa et al. and Seetharama et al.^[10,11] Furthermore, 77.3% (85 out of 110) of patients in Thapa et al.’s study presented within 12 hours of symptom onset, while Seetharama et al. reported 65% (65 out of 100) and Kundu et al. found 60% (183 out of 305) within the same timeframe.^[10-12] The current study observed that 24 patients (48%) presented between 6 to 12 hours after the onset of symptoms, with over 70% presenting within 12 hours.

Regarding risk factors, Kundu et al. noted that 51.47% (157 out of 305) of patients were smokers, followed by diabetes (15.20%, 46 out of 305) and hypertension (22.55%, 69 out of 305). ^[12] Similarly, Seetharama et al. reported 76% (76 out of 100) had a smoking history, with diabetes mellitus and hypertension present in 21% and 23%, respectively. ^[11] Majeed et al. showed that 73.3% (44 out of 60) were smokers, with diabetes and hypertension affecting 13.3% (8 out of 60) and 8.3% (5 out of 60) of patients, respectively. ^[14] The current study identified smoking (60%), diabetes mellitus (12%), and hypertension (6%) as the primary risk factors, aligning with previous research.

Clinical assessments at admission revealed that 21 patients (42%) experienced tachycardia, while 2 patients (4%) had bradycardia, and 3 patients (6%) were in cardiogenic shock. Additionally, 21 patients (42%) were hypertensive at the time of admission. The study indicated that 41 patients presented with ST elevation, and 7 exhibited ST elevation changes with q waves. Successful reperfusion was demonstrated in 30 patients (60%) through the appearance of q waves, biphasic T waves, and T wave inversions. Notably, only 4 patients (8%) sustained persistent ST elevation following thrombolysis, with quicker resolution of ST segment elevation seen in patients treated with thrombolysis compared to those who did not receive it.

At admission, 74% of patients exhibited significantly elevated serum CKMB levels (>100 U/L). Post-thrombolysis, there was an increase in CKMB levels, indicating early peaking and subsequent washout, which differs from the normal peak observed at 24 hours. These findings correlate with those reported by Popa et al. and Halkins et al. ^[14,15] Thapa et al. identified 52.7% (58 out of 110) of patients with anterior wall MI and 37.3% (41 out of 110) with inferior wall MI. ^[10] The current study found that 28 patients (56%) had anterior wall MI and 21 (42%) had inferior wall MI, with additional involvement of other walls; only 1% had isolated lateral wall issues.

In alignment with Seetharama et al., the present study showed that acute left ventricular failure occurred in 10% of patients, while 6% experienced cardiogenic shock, with most complications arising from anterior wall MI. ^[11] The findings are also comparable to those of Thapa et al. and Adhikari et al. ^[10,16] The study by Anuj R Varma et al. reported successful clinical reperfusion in approximately 60% of patients. ^[17]

Following thrombolysis with streptokinase, 38 patients (76%) experienced a 50% reduction in ST segment elevation, and 35 patients (70%) achieved more than 50% pain relief, indicating successful clinical reperfusion in around 70% of cases. Additionally, 34 patients (68%) demonstrated altered lipid profiles, underscoring the significant role of dyslipidemia in STEMI. Anuj R Varma et al. found successful clinical reperfusion in about 62.5% of patients who presented within 12 hours and received thrombolysis. ^[17]

The findings suggested that 16 patients (32%) who presented within 6 hours of symptom onset had successful thrombolysis, and 33 patients (66%) who presented within 12 hours also achieved successful thrombolysis, indicating that earlier presentations enhance the likelihood of effective treatment. Gopalakrishnan et al. reported that all patients exhibited regional wall motion abnormalities (RWMA), with 49% showing left ventricular (LV) dysfunction and 20% developing mitral regurgitation. ^[18] In this study, 90% of patients had LV dysfunction, particularly associated with anterior wall MI, and mitral regurgitation was the most prevalent valvular dysfunction, affecting 72% of patients. Importantly, only 3 patients (6%) experienced mortality post-STEMI after thrombolysis, consistent with Anuj R Varma et al., who reported an 8.75% mortality rate, positioning the current study in alignment with their findings. ^[17]

The study concluded 66% of patients who sought treatment within 12 hours of experiencing symptoms achieved Successful Clinical Reperfusion (SCR) following thrombolysis with Streptokinase. Consequently, it is crucial to enhance early detection of risk factors to mitigate the advancement of coronary heart disease. Additionally, there is a pressing need to raise community awareness about these risk factors, as well as the signs and symptoms of acute myocardial infarction. This knowledge can facilitate timely referrals to coronary care units, ultimately reducing morbidity and mortality rates within the community.

Conflict of interest: No! Conflict of interest is found elsewhere considering this work.

Source of Funding: There was no financial support concerning this work

1. Guha S, Sethi R, Ray S, Bahl VK, Shanmugasundaram S, Kerkar P, et al. Cardiological Society of India: Position statement for the management of ST elevation myocardial infarction in India. Indian Heart J. 2017 Apr;69 Suppl 1(Suppl 1):S63-S97.
2. Elendu C, Amaechi DC, Elendu TC, Omeludike EK, Alakwe-Ojimba CE, Obidigbo B, et al. Comprehensive review of ST-segment elevation myocardial infarction: Understanding pathophysiology, diagnostic strategies, and current treatment approaches. Medicine (Baltimore). 2023 Oct 27;102(43):e35687. 
3. Directorate General of Health Services. Ministry of Health & Family Welfare, Government of India. National Programme for Prevention and Control of Non-communicable Diseases. Guidelines for Management of ST-Elevated Myocardial Infarction. Available from: https://dghs.gov.in/WriteReadData/userfiles/file/NPCDCS/Fin%20%20STEMI%20Guidline.pdf, accessed on September 3, 2023
4. Lawton JS, Tamis-Holland JE, Bangalore S, Bates ER, Beckie TM, Bischoff JM, et al. 2021 ACC/AHA/SCAI guideline for coronary artery revascularization: executive summary: a report of the American College of Cardiology/American Heart Association Joint Committee on Clinical Practice Guidelines. Circulation. 2022 Jan 18;145(3):e4-17.
5. Borja Ibanez, Stefan James, Stefan Agewall, Manuel J Antunes, Chiara Bucciarelli-Ducci, Héctor Bueno, et al, ESC Scientific Document Group, 2017 ESC Guidelines for the management of acute myocardial infarction in patients presenting with ST-segment elevation: The Task Force for the management of acute myocardial infarction in patients presenting with ST-segment elevation of the European Society of Cardiology (ESC), Eur Heart J, Volume 39, Issue 2, 07 January 2018, Pages 119–177,
6. Goyal M, Menon BK, van Zwam WH, Dippel DW, Mitchell PJ, Demchuk AM, D et al. Endovascular thrombectomy after large-vessel ischaemic stroke: a meta-analysis of individual patient data from five randomised trials. Lancet. 2016;387(10029):1723–31.
7. Steg PG, Bonnefoy E, Chabaud S, Lapostolle F, Dubien PY, Cristofini P, et al. Impact of time to treatment on mortality after prehospital fibrinolysis or primary angioplasty: data from the CAPTIM randomized clinical trial. Circulation. 2003 Dec 9;108(23):2851-6.
8. Anupama M, JV SK, Shetty GG. A study to compare fibrinolytic therapy versus primary percutaneous coronary intervention in ST-segment elevation myocardial infarction in a tertiary care hospital. National Journal of Physiology, Pharmacy and Pharmacology. 2022 Nov 1;12(11):1848-.
9. Al-Othman AA, Al-Tawil NG. Effect of thrombolytic therapy on the incidence of early left ventricular infarct expansion in acute anterior myocardial infarction. Oman Med J. 2011 Nov;26(6):431-5.
10. Thapa P, Aryal P, Baniya R. A Study of Clinical Profile and Complications In Patients with ST-Elevation Myocardial Infarction Attending In College of Medical Sciences Teaching Hospital, Bharatpur (Chitwan), Nepal. Nepalese Heart Journal. 2021 Apr 30;18(1):33-7.
11. Seetharama N, Mahalingappa R, Ranjith KG, et al. Clinical profile of acute myocardial infarction patients: a study in tertiary care centre. Int J Res Med Sci.2017, 3(2), 412–419.
12. Kundu SC, Bhattacharjee TD, Banerjee D, et al. Profile of myocardial infarction among the Railroad workers in Eastern India - a six year study. Indian Heart J. 1982;34(3):151-5.
13. Majeed A, Arora RC, Arora S. Study of coronary risk factors in patients with acute myocardial infarction in Bundelkhand region. J Assoc Physicians India. 1998;46(1):76.
14. Popa DM, Macovei L, Moscalu M, Sascău RA, Stătescu C. The Prognostic Value of Creatine Kinase-MB Dynamics after Primary Angioplasty in ST-Elevation Myocardial Infarctions. Diagnostics (Basel). 2023 Oct 6;13(19):3143.
15. Halkin, A, Stone, G, Grines, C. et al. Prognostic Implications of Creatine Kinase Elevation After Primary Percutaneous Coronary Intervention for Acute Myocardial Infarction. JACC. 2006 Mar, 47 (5) 951–961.
16. .Adhikari G, Baral D. Clinical profile of patients presenting with acute myocardial infarction. Int J Adv Med. 2018;5:22833.
17. Varma AR, Chillawar S, Kamble TK, Acharya S. Clinical Markers of Reperfusion in Patients with Acute Myocardial Infarction and Its Prognostic Significance. Int J Recent Surg Med Sci. 2016 Dec;2(2):90-5.
18. Gopalakrishnan S, Govindharaju A. Clinical, ECG and echocardiographic profile of patients presenting with acute ST Elevation Myocardial Infarction (STEMI) in a tertiary care institute at Tamilnadu, South India. J Evid Based Healthc. 2018 Oct 31;5(45):3131-6.