European Journal of Cardiovascular Medicine

Acute myocardial infarction (AMI) remains a significant cause of morbidity and mortality worldwide (1). Timely and accurate diagnosis is crucial for optimal management and outcomes. Electrocardiography (ECG) plays a pivotal role in ACS management, aiding in timely diagnosis, risk stratification, and treatment decisions (2). Early recognition of infarct-related artery involvement guides revascularization urgency, with ECG patterns influencing therapeutic choices. In India, where ACS predominantly manifests as STEMI, rapid access to coronary interventions is crucial. Thrombolytic therapy has revolutionized MI management by restoring blood flow, preserving cardiac function, and enhancing survival rates (3). However, primary percutaneous coronary intervention (PCI) is increasingly preferred over fibrinolytic therapy for STEMI patients, aiming to limit myocardial damage and improve outcomes. This study aims to evaluate the concordance between ECG, 2D-ECHO, and CAG findings in identifying the infarct vessel in AMI.

A total of 75 cases of Acute MI diagnosed by ECG and Cardiac enzymes in patients aged more than 18 years admitted in G.S.L medical college and general hospital during the period of October 2017 to March 2019 were included in the study. All of these patients were randomly selected.

INCLUSION CRITERIA

All patients were selected on the basis of:

Chest pain or discomfort lasting more than 30 minutes

2. ECG showing ST elevation of 1mm or more in limb leads and 2mm or more in precordial leads in two contiguous leads.

Elevation of cardiac enzymes (CPK and CPKMB)

EXCLUSION CRITERIA

Clinical and ECG features suggestive of Pericarditis

ECG features suggestive of Early repolarization syndrome

Patients who do not agree to undergo ECHO or coronary angiogram

Refusal to give consent

Inpatients admitted in the medical ward/ICU/AMCU with acute myocardial infarction were included in this study. A thorough clinical examination according to a predesigned study questionnaire was used to diagnose acute myocardial infarction in patients who satisfied the inclusion and exclusion criteria. Informed consent was taken from all the study subjects. Approval for the study was obtained from the institutional ethical review committee before commencing the study. Patients diagnosed with acute myocardial infarction were evaluated by ECG, 2DECHO and coronary angiogram. ECG findings were correlated with corresponding 2Decho and angiography findings.

ETHICAL ISSUES:

1. Protocol approval from the institutional ethical committee.
2. Informed consent from the study subjects.

STATISTICAL METHODS:

The Statistical software SPSS 22.0, and R environment ver.3.2.2 were used for the analysis of the data and Microsoft word and Excel have been used to generate graphs, tables etc.

The mean age of presentation was 54.72 years, with males comprising 79% of the study population. Hypertension was prevalent in 68% of males and 69% of females, while diabetes was observed in 57% and 62% of males and females, respectively. Smoking and alcohol consumption were common among males, with 80% smokers and 54% regular alcohol consumers. ECG abnormalities included rhythm abnormalities (28%), with complete heart block being the most frequent (7%). Reciprocal ST Segment depressions were noted in 28% of patients.

CAG revealed single-vessel disease (SVD) in 33%, double-vessel disease (DVD) in 55%, and triple-vessel disease (TVD) in 12% of patients. Left anterior descending artery (LAD) involvement was predominant (76%), followed by right coronary artery (RCA, 56%) and left circumflex artery (LCx, 46.7%). The correlation between ECG changes and CAG findings showed sensitivity and specificity of 60% and 94% for LAD involvement, 83% and 85% for RCA involvement, and 26% and 98% for LCx involvement, respectively.

Table.1: Association of ECG/ST variables according to CAG of patients studied

Table.2: Association of ECG/ST variables according to CAG of patients studied

2D-ECHO findings correlated well with CAG, demonstrating sensitivity, specificity, PPV, and NPV of 56%, 94%, 97%, and 40% for LAD involvement, 86%, 94%, 95%, and 84% for RCA involvement, and 100%, 93%, 50%, and 100% for LCX involvement, respectively.

Table.3: Association of 2D Echo parameters according to CAG of patients

Table.4: Association of 2D Echo parameters according to CAG of patients

The study examined 75 randomly selected patients with acute ST elevation myocardial infarction (STEMI). Patients underwent ECG, cardiac enzyme studies, 2D echocardiography, and coronary angiography to identify involved coronary artery occlusions.

Age of Presentation: The mean age was 54.72 ± 11.89, with 79% males and 21% females, predominantly aged 51-60 years. Studies by Wilkinson et al. and Taba Kazemi et al (4). reported similar findings.

Hypertension: 68% of men and 69% of women were hypertensive. Compared to other studies, our incidence was relatively higher.

Diabetes: 57% of men and 62% of women were diabetic, consistent with Bueno et al (5).

Smoking and Alcohol: 80% of male patients smoked, and 54% consumed alcohol. Wilkinson et al (6). and Roy et al. reported similar trends.

Conduction Abnormalities in Acute STEMI: 28% of patients had rhythm abnormalities, with various types noted. Studies by Miene et al (7) and Danielle et al (8). reported comparable incidences.

Importance of Reciprocal Depression Noted in ECG Leads: 28% of patients had reciprocal ST segment depressions. Studies by Parale GP et al (9), Kurum T et al (10) and Jong GP et al (11). highlighted similar findings.

Results of Coronary Angiogram: Single vessel disease (SVD) was found in 33%, double vessel disease (DVD) in 55%, and triple vessel disease (TVD) in 12%. Comparative studies by Younes et al (12) and Roeters et al (13). were consistent.

Correlation of ECG Changes with CAG: Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for identifying coronary artery involvement were calculated. Anterior Wall MI (LAD Artery) and Inferior Wall MI (RCA Artery) criteria and outcomes were discussed, aligned with findings from Englein et al (14), Eskola et al., and Fiol et al (15).

Role of Echocardiography: Correlation of 2D-ECHO with CAG and ECG changes was analyzed. Sensitivity, specificity, PPV, and NPV for detecting regional wall motion abnormalities (RWMA) were determined. Results indicated significant alignment with studies by Richard et al., Parisi et al (16) and Dr. Deepak Gupta et al (17).

Correlation of ECG Changes with 2D ECHO: Sensitivity, specificity, PPV, and NPV for identifying RWMA correlated with ECG changes were discussed for Anterior, Inferior, and Lateral Wall MI. Findings were consistent with studies by Shah et al (18) and Vytilingham (19), and others.

Limitations of the study

In our study female patients formed only 21% as the study group was randomly selected. Among 75 patients of the study only 16 patients were females thereby explaining the significant gender difference in our study.

The number of patients who presented with distal LAD lesion and LMCA occlusion formed only 2% of the study group each thereby it was not possible to identify the role of ECG in identifying the distal LAD and LMCA block.

It was also incidentally noticed that 2 patients in the study group had hyperhomocysteinaemia, however as all the patients were not assessed for the homocyseteine levels, its role as a risk factor for MI could not be assessed

In conclusion, the study underscores the importance of ECG and echocardiography in diagnosing and assessing myocardial infarction, providing valuable insights into patient management and risk stratification. ECG and 2D-ECHO serve as reliable tools in identifying infarct vessels in AMI, demonstrating good concordance with CAG findings. Their high sensitivity and specificity make them valuable in clinical practice for prompt diagnosis and appropriate management of AMI patients. This study contributes to the growing body of evidence supporting the use of ECG and 2D-ECHO in AMI diagnosis and underscores the need for comprehensive, multimodal approaches to enhance patient care.Top of Form

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