European Journal of Cardiovascular Medicine

Heart failure with reduced ejection fraction (HFrEF) represents a significant public health challenge globally, characterized by the heart's inability to pump blood effectively, leading to reduced cardiac output and compromised organ perfusion. This condition is marked by frequent episodes of acute decompensation, which necessitate hospitalization and carry substantial morbidity and mortality risks. Acute decompensation in HFrEF can be triggered by a myriad of factors, both intrinsic and extrinsic, ranging from patient-related behaviors to external medical conditions and medication-related issues.

In India, the prevalence and burden of HFrEF are rising, paralleling global trends, yet the context-specific triggers and their relative impacts are not well-documented. Identifying these triggers is crucial for developing targeted interventions to prevent decompensation and improve patient outcomes. Factors such as excessive salt and water consumption, non-adherence to prescribed medications, acute infections, myocardial ischemia, and systemic hypertension are frequently implicated in acute decompensation episodes. Additionally, less common but significant triggers include arrhythmias, renal failure, inappropriate medication prescription, excessive physical exertion, and socio-behavioral factors like depression and social isolation.^3-6

This study aims to systematically identify and analyze the common triggers of acute decompensation in HFrEF patients admitted to tertiary care hospitals in India. By examining relevant data, we seek to provide a comprehensive overview of the precipitating factors, offering insights into their prevalence and impact. Understanding these triggers within the Indian healthcare context will aid in the formulation of effective management strategies to reduce the frequency and severity of acute decompensation episodes in HFrEF patients.

This research is particularly relevant given the unique dietary, cultural, and healthcare access patterns in India, which may influence the prevalence and impact of specific triggers. The findings are expected to inform clinicians, healthcare policymakers, and stakeholders in designing tailored interventions and educational programs aimed at mitigating the risk of acute decompensation, thereby improving the quality of life and clinical outcomes for patients with HFrEF.

Study Design and Setting

This hospital-based, observational study aimed to identify and analyze the triggers of acute decompensation in patients with heart failure with reduced ejection fraction (HFrEF). The study was conducted at two tertiary care hospitals in India, providing a comprehensive overview of the precipitating factors within this population.

Study Period

Data collection spanned from January to April 2024.

Inclusion and Exclusion Criteria

Inclusion Criteria:

• Patients aged 18 years and above.
• Diagnosed with HFrEF with an ejection fraction of less than 40%.
• Admitted with acute decompensation of heart failure.

Exclusion Criteria:

• Patients with heart failure with preserved ejection fraction (HFpEF).
• Patients with incomplete medical records.
• Patients admitted for reasons other than acute decompensated heart failure.

Data Collection

Data were extracted retrospectively from the medical records of patients admitted with acute decompensated HFrEF at the participating hospitals. The collected data included demographic information such as age and gender, clinical characteristics including medical history and comorbidities (e.g., diabetes, hypertension, chronic kidney disease), and detailed information on the triggers of acute decompensation. Specific triggers examined were excessive salt and water consumption, non-adherence to medication, acute infections (e.g., respiratory or urinary tract infections), myocardial ischemia (new or recurrent myocardial infarction), systemic hypertension, arrhythmias (including acute atrial fibrillation, other tachyarrhythmias, and bradyarrhythmias), renal failure (acute kidney injury or exacerbation of chronic kidney disease), excessive physical exertion, inappropriate prescription or dosing of medications, and socio-behavioral factors such as depression and social isolation. Additionally, outcomes such as length of hospital stay, in-hospital mortality, and the need for intensive care unit (ICU) admission were recorded.

Statistical Analysis

Data were entered into a standardized electronic database and analyzed using Epi Info version 7 statistical software. Descriptive statistics were used to summarize the demographic and clinical characteristics of the study population. Continuous variables were expressed as means and standard deviations, while categorical variables were presented as frequencies and percentages.

The frequency and percentage of each trigger of acute decompensation were calculated to identify the most common precipitating factors. Associations between the triggers and clinical outcomes were assessed using chi-square tests for categorical variables and t-tests for continuous variables. A p-value of less than 0.05 was considered statistically significant. Further, multivariate logistic regression analysis was conducted to adjust for potential confounders and to identify independent predictors of adverse outcomes.

Ethical Considerations

The study was conducted in accordance with the ethical standards of the Declaration of Helsinki. Throughout the study, data confidentiality and patient anonymity were strictly maintained, ensuring that all personal identifiers were removed from the dataset before analysis.

The following tables present the detailed analysis of the triggers of acute decompensation in patients with heart failure with reduced ejection fraction (HFrEF), based on data collected from January to April 2024.

Table 1 presents the demographic characteristics of the 336 patients included in the study. The mean age of the patients was 65.3 years (± 12.4 years), indicating a predominantly elderly population. There was a male predominance, with 202 males (60.1%) and 134 females (39.9%). This gender distribution aligns with the known higher prevalence of HFrEF in men.

Table 1: Demographic Characteristics of the Study Population

Table 2 outlines the clinical characteristics and comorbidities of the study population. Notably, 134 patients (39.9%) had a history of previous heart failure hospitalizations, reflecting a substantial burden of recurrent disease. Comorbid conditions were prevalent, with 185 patients (55.1%) diagnosed with diabetes, 252 patients (75%) with hypertension, 100 patients (29.8%) with chronic kidney disease, and 151 patients (44.9%) with ischemic heart disease. These comorbidities are known to exacerbate heart failure and complicate its management.

Table 2: Clinical Characteristics and Comorbidities

Table 3 identifies the triggers of acute decompensation in the study cohort. The most common trigger was excessive salt and water consumption, reported in 101 patients (30.1%), highlighting dietary non-compliance as a significant issue. Non-adherence to medication was the second most common trigger, affecting 84 patients (25%). Acute infections, such as respiratory and urinary tract infections, were identified in 67 patients (19.9%). Myocardial ischemia, either new or recurrent, was a trigger in 59 patients (17.6%), while systemic hypertension contributed to decompensation in 50 patients (14.9%). Arrhythmias, including acute atrial fibrillation and other tachyarrhythmias, were noted in 43 patients (12.8%). Renal failure was a trigger in 33 patients (9.8%), excessive physical exertion in 25 patients (7.4%), inappropriate prescription or dosing of medications in 17 patients (5.1%), and socio-behavioral factors like depression and social isolation in 14 patients (4.2%).

Table 3: Triggers of Acute Decompensation

Table 4 presents the outcomes of the study population. The mean length of hospital stay was 7.2 days (± 3.1 days), indicating a significant hospitalization burden. In-hospital mortality was observed in 25 patients (7.4%), reflecting the severity of acute decompensation in this cohort. Additionally, 68 patients (20.2%) required admission to the intensive care unit (ICU), underscoring the critical nature of many cases.

Table 4: Outcomes

Table 5 explores the association between specific triggers of decompensation and the need for ICU admission. Excessive salt and water consumption was significantly associated with ICU admission, occurring in 38 patients (55.9%) who were admitted to the ICU compared to 63 patients (23.5%) who were not, with a p-value of <0.001. Similarly, non-adherence to medication was more common in ICU-admitted patients (29 patients, 42.6%) compared to those not admitted to the ICU (55 patients, 20.5%), with a p-value of <0.001. Acute infections, myocardial ischemia, systemic hypertension, arrhythmias, renal failure, excessive physical exertion, inappropriate prescription/dosing, and socio-behavioral factors did not show statistically significant differences between ICU and non-ICU admissions.

Table 5: Association Between Triggers and ICU Admission

Table 6 provides the results of the multivariate logistic regression analysis identifying independent predictors of in-hospital mortality. Age was a significant predictor, with an odds ratio (OR) of 1.05 (95% CI: 1.02-1.08, p < 0.001), indicating that older patients had a higher risk of mortality. Excessive salt and water consumption was also a significant predictor (OR: 2.5, 95% CI: 1.3-4.9, p = 0.007), as was non-adherence to medication (OR: 2.1, 95% CI: 1.1-4.1, p = 0.021). Renal failure significantly increased the risk of mortality (OR: 3.0, 95% CI: 1.4-6.4, p = 0.005). Acute infections and myocardial ischemia were not significant predictors of in-hospital mortality in this analysis.

Table 6: Multivariate Logistic Regression Analysis for Predictors of In-Hospital Mortality

This study provides a detailed analysis of the triggers and outcomes of acute decompensation in patients with heart failure with reduced ejection fraction (HFrEF) in an Indian context. By examining data from 336 patients admitted to tertiary care hospitals, this research identifies key factors that precipitate acute decompensation and highlights their implications for clinical practice. The findings are compared with existing literature to offer a comprehensive understanding of the results.

Table 1 presents the demographic characteristics of the study population, with a mean age of 65.3 years and a male predominance (60.1%). This demographic profile aligns with global data on HFrEF patients, reflecting a higher prevalence in older adults and males.  Many Studies similarly reported a higher incidence of HFrEF in older males, indicating consistent demographic patterns across different populations.^7-9

Table 2 outlines the clinical characteristics and comorbidities, revealing that 39.9% of patients had previous heart failure hospitalizations, indicating a significant burden of recurrent disease. Comorbid conditions were prevalent, with diabetes in 55.1%, hypertension in 75%, chronic kidney disease in 29.8%, and ischemic heart disease in 44.9%. These findings are consistent with other studies which highlight the role of comorbidities in exacerbating heart failure and complicating its management.^10-11

Table 3 identifies the triggers of acute decompensation, with excessive salt and water consumption being the most common (30.1%). This finding is corroborated by Tsuyuki et al., who emphasize dietary non-compliance as a significant issue in heart failure management. Non-adherence to medication (25%) was the second most common trigger, consistent with studies which highlight the critical role of medication adherence in chronic disease management.^1,12,13

Acute infections (19.9%) were also a significant trigger, reflecting findings of other researches who reported respiratory and urinary tract infections as common precipitants of acute decompensation. Myocardial ischemia (17.6%) and systemic hypertension (14.9%) were other notable triggers, aligning with previous research, who underscore the impact of ischemic events and hypertensive crises on heart failure exacerbations.^14,15

Arrhythmias (12.8%) and renal failure (9.8%) were significant but less common triggers. The association between arrhythmias, especially atrial fibrillation, and heart failure is well documented. Similarly, the interplay between renal dysfunction and heart failure, often referred to as the cardiorenal syndrome. Socio-behavioral factors, including depression and social isolation (4.2%), were less frequently reported but are significant contributors to poor heart failure outcomes, as noted by other authors.^16-18

Table 4 presents the outcomes, with a mean length of hospital stay of 7.2 days, an in-hospital mortality rate of 7.4%, and an ICU admission rate of 20.2%. These outcomes underscore the severe burden of acute decompensation in HFrEF. Comparatively, studies from developed countries, report similar lengths of stay but often lower mortality rates, reflecting differences in healthcare infrastructure and access.^19,20

Table 5 explores the association between specific triggers and ICU admission. Excessive salt and water consumption was significantly associated with ICU admission (55.9% vs. 23.5%, p < 0.001), highlighting the critical impact of dietary non-compliance. Non-adherence to medication was also significantly associated with ICU admission (42.6% vs. 20.5%, p < 0.001). These associations emphasize the need for patient education and adherence support, consistent with findings of previous research.^20-22

Other triggers, such as acute infections, myocardial ischemia, systemic hypertension, arrhythmias, renal failure, excessive physical exertion, inappropriate prescription/dosing, and socio-behavioral factors, did not show statistically significant differences between ICU and non-ICU admissions. This may indicate that while these factors are important, their direct impact on the severity of decompensation requiring ICU care may be less pronounced than dietary and medication adherence issues.

Table 6 provides the results of the multivariate logistic regression analysis for predictors of in-hospital mortality. Age was a significant predictor (OR: 1.05, 95% CI: 1.02-1.08, p < 0.001), indicating that older patients had a higher risk of mortality. This finding is consistent with numerous studies, including those by Lee et al., which highlight increased vulnerability with advancing age.^14-19

Excessive salt and water consumption (OR: 2.5, 95% CI: 1.3-4.9, p = 0.007) and non-adherence to medication (OR: 2.1, 95% CI: 1.1-4.1, p = 0.021) were also significant predictors of mortality. These results underscore the importance of dietary compliance and medication adherence in improving patient outcomes. Renal failure (OR: 3.0, 95% CI: 1.4-6.4, p = 0.005) significantly increased the risk of mortality, aligning with findings from previous research, highlighting the complex interplay between renal function and heart failure outcomes. Acute infections and myocardial ischemia were not significant predictors of in-hospital mortality in this analysis, suggesting that their impact may be mitigated by prompt and effective treatment.^23-25

The findings from this study have important implications for clinical practice in India and similar healthcare settings. Addressing dietary non-compliance and enhancing medication adherence through patient education and support systems are critical. Additionally, prompt management of infections, ischemic events, and hypertensive crises can mitigate the risk of acute decompensation. Implementing comprehensive care plans that include regular monitoring, patient education, and support for lifestyle modifications can help reduce hospitalizations and improve outcomes for HFrEF patients.

Limitations and Future Directions

This study has several limitations. As an observational analysis, it may introduce biases related to data accuracy and completeness from medical records. The study is also confined to two tertiary care hospitals, potentially limiting the generalizability of the findings to broader populations. Additionally, the reliance on documented triggers may overlook less frequently recorded but significant factors. Future prospective studies with larger, more diverse populations and multi-center collaborations are needed to confirm these findings and address these limitations. Additionally, exploring the impact of tailored intervention programs on reducing hospitalizations and improving outcomes in HFrEF patients would be valuable.

This study highlights the critical triggers of acute decompensation in HFrEF patients, particularly emphasizing the roles of excessive salt and water consumption and non-adherence to medication. These findings underscore the importance of patient education and adherence support in managing heart failure. Age, dietary non-compliance, medication non-adherence, and renal failure were significant predictors of in-hospital mortality, emphasizing the need for comprehensive care plans that include regular monitoring and lifestyle modifications. By addressing these factors, healthcare providers can reduce hospitalizations and improve outcomes for HFrEF patients. Future research should focus on validating these findings through prospective studies and exploring tailored interventions to further mitigate the risks associated with acute decompensation.

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