Short and Long-Term Clinical Outcomes in Octogenarian Patients With Non-ST-Elevation Myocardial Infarction: A Comparative Analysis of Revascularization Strategies Versus Medical Management

Introduction: As the primary cause of morbidity and mortality among older individuals, cardiovascular disease remains a major concern. Choosing between revascularization and medical management of elderly patients remains controversial. This study aims to evaluate the clinical implications of these treatment approaches in the context of non-ST-elevation myocardial infarction (NSTEMI) in octogenarian patients. Methods: This observational cohort study involved 41 octogenarian patients who were diagnosed with NSTEMI from 2019 to 2021 and were managed by revascularization (with either percutaneous coronary intervention, coronary artery bypass graft surgery, or both) or conservative medical therapy. All NSTEMI patients were diagnosed based on symptoms, electrocardiographic changes, and cardiac biomarkers. The study compared the short- and long-term outcomes of 13 patients in the revascularization group and 28 in the medical therapy group. Results: Overall, the mean patient age was 84.63 years. Eighteen patients were men (43.9%), and 23 were women (56.1%). The most prevalent disease among the sample was hypertension (34 patients, 82.9%), followed by diabetes mellitus (27 patients, 65.9%) and prior ischemic heart disease (21 patients, 51.2%). Almost all patients in the revascularization-treated group developed complications after the procedure (84.6%), while 46.4% of the patients in the medication-only group developed a complication later on. The revascularization-treated group showed higher mortality rates in both the short- and long-term (23.1% and 38.5%, respectively) compared to the medication-only group, which showed better survival rates numerically in both the short- and long-term (14.3% and 32.1%, respectively). This was not statistically significant. Conclusion: Revascularization treatment in elderly patients with NSTEMI was associated with a higher risk of complications and a higher mortality rate compared with conservative medical management. Patients managed with only medications had a better survival rate in both the short- and long-term.


Introduction
As the leading cause of morbidity and mortality among the elderly population, cardiovascular disease remains a significant concern [1].With advancements in health care services, the aging population is experiencing an increase in life expectancy, which emphasizes the need for a comprehensive understanding of cardiovascular diseases and effective strategies to address the health challenges they cause [1].However, regarding treatment options, the choice between revascularization and conservative medical management in elderly patients remains controversial [2,3], necessitating further research.While revascularization has improved clinical outcomes in patients with acute coronary syndrome, its applicability and effectiveness in the elderly population are not yet well established [2,4].
Physicians often opt for a conservative approach when contemplating revascularization procedures for their octogenarian patients, acknowledging the heightened risk of complications associated with revascularization and the lack of supporting evidence for its efficacy in this population [2,5].This knowledge gap underscores the importance of the present study comparing the effectiveness of revascularization with that of medical management in elderly patients, particularly those with non-ST-elevation myocardial

Follow-up and end-points
All patients who were diagnosed and managed in KAMC during the study period were followed for a total of three years.The end-points were obtained on two occasions, of 1 year and 3 years.The measured outcomes during the follow-up time included the development of complications (e.g., nonfatal myocardial infarction, stroke, heart failure requiring hospitalization, etc.) as well as cardiovascular disease-related death and allcause mortality.

Statistical analysis
IBM Statistical Product and Service Solutions (SPSS) (Version 26) was used.Numerical data are presented as mean±SD.For categorical variables, frequencies and percentages are used.Comparisons between groups were made using the Student's t-test.The chi-square test was used for categorical values.Survival analysis using the Kaplan-Meier curve was included to compare the survival rates between the medications group and the revascularization group in terms of cardiovascular death and all-cause mortality.A 95% confidence interval with a significance level of 5% was used for testing differences between variables.

Results
A total of 41 patients were included in the study.Table 2 compares the two groups regarding various factors, including demographics, clinical history, and medication use.Notably, no significant associations were found between these factors and the type of management (P > 0.05).All-cause mortality also showed no association with the type of management (P > 0.05).

Studied variables Medication only Revascularization
No  This study thoroughly assessed the clinical significance and effectiveness of revascularization versus medical therapy in octogenarians with NSTEMI, aiming to compare favorable outcomes between the two groups.The results revealed that a large proportion of patients in the revascularization-treated group (84.6%) developed complications, either due to the nature of their disease or related to the procedure.In the medication-only group, 46.4% of the patients experienced complications, but later (Table 3).Age, anemia, and use of beta-blockers after discharge showed significant association with the type of management (P < 0.000, P < 0.046, P < 0.039, respectively).As shown in Figures 1-2, we compared the survival rate between the revascularization and medical therapy groups regarding cardiovascular death and all-cause mortality.The medical therapy group exhibited slightly better survival rates for both cardiovascular death and all-cause mortality, though the differences were not statistically significant (P>0.05).

Discussion
Our results demonstrate that the revascularization-treated group had a higher mortality rate than the medication-only group, which exhibited better survival in both the short-and long-term.Elderly patients are known to be at higher risk for multiple health conditions and have a greater extent of atherosclerotic disease, making revascularization technically more challenging.However, recent evidence from Germany and Sweden has suggested that PCI in the older population leads to favorable outcomes [6,7].A previous systematic review and meta-analysis published by McKellar et al. reviewed 32 studies to investigate the outcomes of PCI among the elderly.They concluded that PCI had acceptable short-and long-term outcomes among octogenarians; however, most reviewed studies had low-level evidence [8].
Our results are inconsistent with previous findings, possibly due to several reasons.First, there is the nature of the population.Even without genetic changes, the risk of cardiovascular disease, in general, can be altered by changes in the environment resulting from migration to different geographic locations, modifications in lifestyle choices, and shifts in social policies and cultural practices [9].Our review of the literature showed no previous studies conducted among the Saudi population on the issue of treatment strategy.Therefore, we suggest conducting local investigations to gain a deeper understanding of the society, which will aid in transitioning from standardized to customized management tailored to the community.Second, methodological aspects may have contributed to the present results, such as the limited number of participants in the study and the difference in the number of patients in the two groups.Third, some of our patients in the revascularization-treated group received further treatment in the form of CABG, which may have contributed to the higher mortality rates, as suggested by previous studies [10][11][12].Moreover, a study published by Santos et al. showed a mortality rate of 8.7% among 1,628 patients who underwent CABG and identified the following risk factors: age over 65 years, being on dialysis, having type I neurologic dysfunction, use of intra-aortic balloon pump, serum creatinine level on admission and peak values over 0.4 mg/dL, cardiopulmonary bypass time of more than 115 minutes, and time window between hospital admission to the surgical procedure [13].
Our three-year survival analysis for all-cause mortality revealed a higher mortality rate for the revascularization-treated group than for the medication-only group (38.5% vs 32.1%, respectively) (Table 3).However, the difference was not statistically significant.These findings align with a meta-analysis of randomized controlled trials involving patients with all forms of coronary artery disease.A sensitivity analysis of the longer-term follow-up trials revealed a non-significant reduction in mortality rate in the revascularization-treated group among patients with myocardial infarction.In addition, revascularization did not impact three-year all-cause mortality in patients with stable coronary artery disease [14].
Several factors influence the decision to proceed with revascularization in elderly patients.Comorbid illnesses, clinical frailty, and the patient's functional status must be considered.Comorbid illnesses include but are not limited to, arthritis and cerebral, renal, and pulmonary diseases [15].Reports show patients with a lower risk profile were more likely to be selected for revascularization management [16,17].However, we can still not determine the specific factors influencing the decision to opt for PCI in managing older adult patients.Nevertheless, a previous cohort study confirmed that younger age, male gender, lower heart rate, lower systolic blood pressure, and no history of hypertension or stroke were determinants for selecting PCI for octogenarian patients [6].

Strengths and limitations
This study provided an extraordinary opinion regarding the decision to choose revascularization treatment in the case of octogenarian patients in the Saudi community.The study encourages and lays the groundwork for future randomized trials to be conducted locally.Despite all efforts, the study has several limitations.First, confounding factors from unmeasured variables could not be ruled out completely.Second, the limited sample size and different number of patients in each group may have remarkably affected our findings.This limitation depended on available data on patients who presented to our center between 2017 and 2021, over which we had no control.Lastly, there is the possibility of bias resulting from the study's retrospective nature, as our data were obtained from patient files.Missed documentation and recall bias are inherent limitations that cannot be avoided in this type of study.

Conclusions
Our study revealed that numerous patients in the revascularization-treated group developed complications after the procedure, while fewer complications were observed among the patients treated with only medication.The study also demonstrated that the revascularization-treated group had a higher mortality rate compared with the medical-therapy group, which showed better survival in both the short-and longterm.
However, these numbers were statistically non-significant.We suggest conducting additional local investigations involving multiple centers, larger numbers of patients, and randomized trials to gain a deeper understanding of our society in Saudi Arabia, which will aid in transitioning from standardized to customized management tailored to the community.

TABLE 3 : Summary of complications and short-and long-term outcomes among the included patients (n=41)
Abbreviations: MI: myocardial infarction; HFRH: heart failure requiring hospitalization; CV death: cardiovascular diseases-related death