Acute Coronary Syndrome (ACS) is a broad clinical term used to describe a spectrum of conditions that result from the sudden reduction or cessation of blood flow to the heart muscle. This encompasses a range of serious cardiovascular events, including unstable angina, non-ST-elevation myocardial infarction (NSTEMI), and ST-elevation myocardial infarction (STEMI). These events are typically the result of the rupture of an

atherosclerotic plaque and the subsequent formation of a thrombus, which obstructs the coronary artery and disrupts blood flow. ACS is a major cause of morbidity and mortality worldwide, placing a significant burden on healthcare systems and requiring rapid intervention to restore coronary perfusion, limit myocardial injury, and prevent complications such as heart failure and arrhythmias.

The treatment of ACS aims to achieve rapid reperfusion, mitigate further thrombotic events, and optimize long-term cardiovascular outcomes. Among the cornerstone therapies for ACS are antiplatelet agents, which inhibit platelet aggregation and thrombus formation. These medications, including P2Y12 inhibitors, are particularly important in ACS management. The P2Y12 receptor is a key mediator of platelet activation, and by inhibiting this receptor, P2Y12 inhibitors help prevent the formation of blood clots that may worsen the ischemic injury to the heart. Drugs in this class include Clopidogrel, and Ticagrelor, each of which has demonstrated efficacy in reducing the incidence of major adverse cardiovascular events (MACE), such as death, recurrent myocardial infarction (MI), and stroke

Despite the proven efficacy of P2Y12 inhibitors in preventing thrombotic complications in ACS, there are several important considerations in their clinical use. The selection of an appropriate P2Y12 inhibitor, the timing and duration of therapy, and the monitoring of potential adverse effects all require careful attention. Side effects (such as insomnia, dyspnea, nausea and vomiting) , including bleeding complications, are a particular concern, especially in patients who are elderly, frail, or have comorbid conditions such as renal impairment. Additionally, drug interactions can influence the pharmacokinetics of P2Y12 inhibitors, potentially modifying their effectiveness or increasing the risk of bleeding. These factors underscore the importance of personalized treatment approaches in ACS, as a one-size-fits-all strategy may not be optimal for all patients.

In the context of ACS, the use of P2Y12 inhibitors also raises important questions about the occurrence of chest pain despite treatment, recurrent myocardial infarctions (repeat MI), and the influence of Prothrombin Time (PT) and International Normalized Ratio (INR) values. Chest pain is a common symptom that can persist after initial treatment and may signal inadequate myocardial perfusion or the need for further intervention. The occurrence of repeat myocardial infarction in patients who are on appropriate antiplatelet therapy is another area of concern, as it suggests that the treatment regimen may be insufficient or that other underlying issues, such as stent thrombosis or persistent atherosclerotic burden, may be contributing factors. Additionally, PT and INR are frequently monitored in patients receiving anticoagulation therapy and may be relevant in the management of ACS, particularly in patients receiving dual antiplatelet therapy (DAPT) or concurrent anticoagulation. Variability in these markers, especially when used to assess the effectiveness of anticoagulant therapy in conjunction with antiplatelet agents, may provide important insights into the pharmacodynamics

of treatment and patient-specific responses.

Given these complexities, the current study aims to evaluate the real-world effectiveness and safety of P2Y12 inhibitors in the management of ACS, focusing on key outcomes such as side effects, chest pain, repeat MI, and the effectiveness of treatment as indicated by PT and INR levels. Specifically, the objectives of this prospective observational study include:

Identifying and analyzing the side effects associated with P2Y12 inhibitors in ACS patients. This includes bleeding events, insomnia, dyspnea, nausea and vomiting and other adverse reactions that may limit the tolerability and safety of these medications.

Assessing the occurrence of chest pain in patients despite treatment with P2Y12 inhibitors, to determine whether persistent symptoms correlate with treatment failure or other underlying issues

Examining the incidence of repeat myocardial infarction during treatment, with a focus on understanding whether the occurrence of recurrent events is related to the adequacy of P2Y12 inhibition or other contributing factors such as stent thrombosis or patient non-compliance

The study was conducted at Apollo Hospital, Kakinada, over a six-month period, from August 2024 to February 2025, with a sample size of 100 cases. It was a prospective observational study involving both male and female patients, including geriatrics, aged 20-80 years, who were receiving P2Y12 inhibitor therapy (clopidogrel or ticagrelor). Data were collected on patient demographics, lab parameters (Prothrombin time, INR), side effects, symptoms, and repeat myocardial infarction (MI) during a 1-month follow-up. The study excluded pregnant and lactating women, as well as patients on drugs affecting side effects or bleeding profiles. Ethical approval was obtained from the Institutional Ethical Committee, and informed consent was collected from all participants. Descriptive statistics were used for data analysis, and findings were represented through bar graphs.

Among patients taking P2Y12 inhibitors, 66% are on Clopidogrel and 34% on Ticagrelor. After taking P2Y12 inhibitors, 91% of patients (61% male and 30% female) experienced side effects, while 9% did not. Among these patients, 9% (4% male and 5% female) had a repeat MI, and 91% did not. Additionally, 21% (11% male and 10% female) experienced chest pain, while 79% did not, Furthermore, 86% of patients had changes in Prothrombin Time, and 14% showed no changes. No significant INR changes were noted.

Table-1 P2Y12 inhibitors drugs

              Figure-1

          Table-2 Representation of diagnosis in associated with P2Y12 inhibitors therapy

Figure-2

            Table-3 Side Effect

            Figure-3

    Table-4 Drug wise side effect distribution of patient taking P2Y12 inhibitors of acute coronary syndrome patients

   Figure-4

                 Table-5 Symptoms

                 Figure-5

                       Table-6: Repeat MI

            Figure-6

              Table-7 Prothrombin Time

           Figure-7

           Table-8 INR ratio in patients of p2y12 inhibitors therapy

          Figure-8

In this study, 100 patients with various morbidities were prescribed Clopidogrel (66 patients) or Ticagrelor (34 patients) at Apollo Hospital, Kakinada, from August 2024 to February 2025. We observed side effects, symptoms, repeat MI, and prothrombin time (PT) and INR profiles. Acute coronary syndrome primarily affected the 51–80 years age group. 91% of patients experienced side effects, with nausea, vomiting, and insomnia being the most common. Side effects were more prevalent in males and patients aged 61–70. Chest pain occurred in 21% of patients, and repeat MI was observed in 9%. PT changes were seen in 86% of patients, but no significant INR changes were noted. Overall, middle-aged to older patients experienced fewer repeat symptoms and MIs.

In conclusion, this study evaluated the clinical management of ACS patients treated with P2Y12 inhibitors, Clopidogrel and Ticagrelor, over a six-month period. Most patients experienced side effects, with nausea, vomiting, and insomnia being the most common. Clopidogrel was more frequently used across all age groups, while Ticagrelor was primarily prescribed to older patients with severe conditions. The study found that 91% of patients experienced side effects, and a small percentage had repeat chest pain or MI. Despite some changes in prothrombin time, there were no significant INR changes. Overall, both medications effectively reduce major cardiovascular events, with Ticagrelor being preferred for high-risk patients, and Clopidogrel remaining a suitable option for those with contraindications to Ticagrelor.

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