|Year : 2020 | Volume
| Issue : 4 | Page : 155-160
Acute Decompensated Heart Failure with Reduced Ejection Fraction: Common Etiological Cause and Predictor of Mortality in the Nepalese Population
Rajesh Nepal MD, DM , Manoj Kumar Choudhary MD , Sushant Katuwal MD , Sunil Babu Khanal MBBS , Roshna Adhikari MBBS , Madhav Bista MD , Sahadev Dhungana MD, DM
Department of Internal Medicine, Cardiology Unit, Nobel Medical College Teaching Hospital, Biratnagar, Nepal
|Date of Submission||23-Jun-2020|
|Date of Decision||04-Aug-2020|
|Date of Acceptance||11-Sep-2020|
|Date of Web Publication||09-Feb-2021|
Dr. Rajesh Nepal
Department of Internal Medicine, Cardiology Unit, Nobel Medical College Teaching Hospital, Biratnagar
Source of Support: None, Conflict of Interest: None
Background: Heart failure with reduced ejection fraction (HFrEF) is one of the most common cardiac diseases causing hospital admission, with a very high short- and long-term mortality rate. The study aims to assess the short-term mortality rate of acute decompensated HFrEF and its correlation with the baseline characteristics in a Nepalese population. Methods: Patients with acute decompensated HFrEF admitted in the unit were prospectively enrolled in this study and were followed up for 3 months. Patients who died and those who did not die were compared using the Chi-square test for categorical variables and Student's t-test was used for the comparison of continuous variables. Results: A total of 100 patients were included in the study. The mean age of the patient was 60 ± 16.18 years, with 55% of the participants being male. Atrial fibrillation was documented in 17% and 16% had bundle branch block. Idiopathic dilated cardiomyopathy was seen in 56% of the participants and was found to be the most common cause of HFrEF, followed by coronary artery disease (18%). Pleural effusion was present in 17% of the patients, out of which bilateral effusion was more common (8%). Twenty-nine percent of the patients died during the 3 months follow-up period. Dyslipidemia, hypertension, ejection fraction, baseline hemoglobin, and creatinine level were significant predictors for mortality (P < 0.05 for all). Conclusion: Dilated cardiomyopathy was the most common cause of acute decompensated HFrEF in the Nepalese population. A very high 3-month mortality rate (29%) was recorded. The presence of cardiovascular risk factors, reduced ejection fraction, baseline hemoglobin, and creatinine levels were significant predictors of mortality in acute decompensated HFrEF patients.
Keywords: Cardiovascular risk factors, heart failure, mortality, reduced ejection fraction
|How to cite this article:|
Nepal R, Choudhary MK, Katuwal S, Khanal SB, Adhikari R, Bista M, Dhungana S. Acute Decompensated Heart Failure with Reduced Ejection Fraction: Common Etiological Cause and Predictor of Mortality in the Nepalese Population. J Clin Prev Cardiol 2020;9:155-60
|How to cite this URL:|
Nepal R, Choudhary MK, Katuwal S, Khanal SB, Adhikari R, Bista M, Dhungana S. Acute Decompensated Heart Failure with Reduced Ejection Fraction: Common Etiological Cause and Predictor of Mortality in the Nepalese Population. J Clin Prev Cardiol [serial online] 2020 [cited 2021 Mar 2];9:155-60. Available from: https://www.jcpconline.org/text.asp?2020/9/4/155/308978
| Introduction|| |
Heart failure (HF) is considered as an emerging epidemic, affecting around 26 million people worldwide. It is a common cardiovascular condition with increasing incidence and prevalence. In India, annually, 491600-1.8 million are diagnosed with HF due to various causes such as coronary artery disease (CAD), hypertension, obesity, diabetes, and rheumatic heart disease (RHD), although it may be still underestimated. After the diagnosis of HF, crude case fatality rates have been reported to be 20% and 45%, at 30 days and at 1 year, respectively. A reduced left ventricular ejection fraction (LVEF) was found to be associated with an increased risk of sudden death., In HF patients, younger age was a powerful predictor of survival. Anemia has also been associated with higher HF severity and mortality in some studies. Similarly, the creatinine levels are considered prognostic factors in hospitalized patients with HF.,, A previous study from Nepal reported in-hospital mortality of 9.4% in HF patients. Although the overall prevalence of RHD is still higher in Nepal and was one of the most common causes of HF previously, the incidence of CAD is on rise in Nepal., More than 60% of patients with HF in the US might be attributable to CAD compared to the other risk factors such as hypertension, obesity, diabetes, and smoking., However, a recently published study from Nepal reported idiopathic dilated cardiomyopathy (DCM) accounting for 50% of all clinically diagnosed causes for HF patients. Despite advances in the treatment, chronic HF with systolic dysfunction remain at high risk for re-hospitalization and higher mortality., This may be attributed to the advanced age of the population, progressive disease, and persistently high event rates.
To the best of our knowledge, there is a paucity of data related to etiological factors and predictors of mortality in acute decompensated HF patients in Nepal. Our study aims to assess 90-day outcomes in patients with HFrEF admitted with New York Heart Association (NYHA) class III/IV and the factors associated with re-admissions and mortality.
| Methods|| |
This was a prospective descriptive study done at Nobel Medical College, Biratnagar for 18 months. A cohort of 100 consecutive eligible patients with a primary diagnosis of HF with reduced ejection fraction (HFrEF) who were discharged from our cardiac care unit were selected. The diagnosis of acute decompensated HFrEF was made by cardiologists based on the HF guidelines. Inclusion criteria were age >16 years, NYHA III/IV, LVEF <45%. Chronic organ failure like chronic kidney disease requiring dialysis, chronic liver disease, advanced chronic obstructive pulmonary disease with cor-pulmonale, nonambulating stroke, HF with preserved ejection fraction (HFpEF) and those not willing to give consent were excluded. LVEF was calculated on echocardiography by the eyeballing method by expert operators. All enrolled patients were evaluated clinically and all of them underwent routine cardiac investigations and echocardiography (first assessment). The study complies with the declaration of Helsinki and was approved by the ethical committee of the Nobel Medical College Teaching Hospital. Signed informed consent was obtained from all participants.
The patients were followed up for 3 months on their follow-up visits in outpatient department, subsequent readmissions and/or through telephonic calls.
Ischemic heart disease heart failure
HF patients admitted with a history of chronic stable angina or acute coronary syndrome or with evidence of significant CAD by coronary angiogram were labeled as ischemic heart disease HF.
Idiopathic/dilated cardiomyopathy-heart failure
Patients with DCM and or no obvious cause of HF were found.
Valvular heart disease
Left ventricular systolic dysfunction in the presence of a significant valvular lesion.
Alcoholic heart failure
HF in the presence of significant alcohol consumption and no other obvious cause.
HF beginning at 1-month prior or 5-month postpartum period.
Any of the following values in fasting sample taken within 24 h of the event were as follows: total cholesterol ≥200 mg/dL, low-density lipoprotein cholesterol ≥130 mg/dL, triglycerides ≥150 mg/dL, and high-density lipoprotein cholesterol ≤40 mg/dL or patients already on medication for dyslipidemia.
Hypertension included systolic blood pressure ≥140 mmHg or diastolic blood pressure ≥90 mmHg and/or concomitant use of antihypertensive medications.
Optimal medical management was defined as a combination of beta-blockers, angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin receptor blockers (ARBs), and aldosterone receptor blockers in patients with left ventricular systolic dysfunction (LVSD, EF < 45%). This was in addition to diuretics and digoxin, as and when necessary.
The demographic, laboratory, and echocardiographic data were analyzed using analysis of variance (ANOVA), and the Bonferroni correction was applied in the post hoc analyses. Categorical variables were reported as a percentage (%), and continuous variables were reported as the mean ± standard error of the mean. Groups were compared using the Chi-square test (cross-tabulation method) for categorical variables and Student's t-test was used for the comparison of continuous variables. P < 0.05 was considered statistically significant, with a 95% confidence interval. Data were analyzed using the Statistical Package for the Social Sciences (SPSS) version 17.0 for Windows (SPSS, Inc., Chicago, Illinois, and the USA).
| Results|| |
Demographic and study characteristics
Altogether, 100 patients were included in this study, with equally divided male and female ratio. The mean age of the patient was 60 ± 16.18 years (male 61.18 ± 15.76, female 58.28 ± 16.60). Among the enrolled HF patients, 55% of patients aged > 60 years of age. Both age and sex did not correlate significantly with mortality (P = 0.25 and 0.36 respectively). The age distribution chart is presented in [Figure 1].
Laboratory and chest X-ray findings
Twenty-four percent of the patients with acute decompensated HF had a history of hypertension; among them, 48% of patients who expired had a history of hypertension, whereas dyslipidemia was observed in 66% of patients who expired. Seventeen percent of the patient had pleural effusion in chest X-ray. Eight percent of the patients had bilateral pleural effusion, while 6% had only right and 3% had isolated left-sided pleural effusion [Table 1]. The mean hemoglobin level of the study population was 11.92 ± 2.12 g/dL. Mean hemoglobin in survival group was higher (12.16 g/dL) compared to that in expired group (11.35 g/dL) (P = 0.020). The mean creatinine of the study population was 1.49 ± 0.95 mg/dL. Survival group had mean creatinine lower (1.37 mg/dL) compared to expired group (1.81 mg/dL) (P = 0.038) [Table 2].
Electrocardiogram and echocardiographic findings
Atrial fibrillation (AF) was reported in 17 patients, 16 patients had conduction abnormality out of which fifteen had left bundle branch block (LBBB) and one patient had right bundle branch block. Both AF and conduction defects did not correlate positively with mortality [Table 1].
Mean LVEF was 24.99 ± 6.57%, while mean pulmonary artery systolic pressure was 36.13 ± 8.03 mmHg. The mean left ventricle end-diastolic diameter (LVEDD) was 58.18 ± 8.56 mm, while the mean left atrium (LA) size was 40.02 ± 8.08 mm. Pericardial effusion was present in 11% of the patient. Mild mitral regurgitation (MR) was present in 34%, moderate in 34%, and severe MR in 6%. None of the echocardiographic parameters except ejection fraction correlated positively with mortality [Table 1] and [Table 2].
Hospital stay and mortality
There was no significant difference in the duration of hospital stay in both survivals (4 ± 3 days) versus expired group (5 ± 3 days). Ninety days mortality rate in acute decompensated HF patients was 29% of the total population. The mortality rate was not different between male (17%) and female (12%) HF patients. The mean age in the dead patient's group was 62 years, while in the survival group, it was 59 years [Table 1]. History of hypertension and dyslipidemia were significantly associated with mortality (P ≤ 0.004 for both). Hemoglobin less than 12 g/dL, and creatinine more than 1.2 mg/dL were also significantly associated with higher mortality (P ≤ 0.038 for both). LVEF was the strong predictor of mortality in HF patients (P = 0.039) [Table 3].
Etiologies of heart failure
In majority of the patients, definitive etiology could not be determined and hence were considered idiopathic DCM (56%). DCM was considered to be the most common cause of HF in the Nepalese population. CAD was diagnosed either by coronary angiography or if the clinical symptoms, electrocardiogram (ECG), and Echocardiographic findings are consistent with CAD. In this study, 18% of HF patients were diagnosed with ischemic cardiomyopathy. Twelve patients were diagnosed as alcoholic cardiomyopathy. Eight patients had valvular heart disease, mostly RHD and four patients had peripartum cardiomyopathy (PPCM). Most of these diagnosed patients also had hypertension and among them, only two patients (2%) were considered hypertensive cardiomyopathy with a history of long-term hypertension and absence of other likely causes among 24 hypertensive subjects [Table 4]. None of the etiology significantly correlates with mortality (P = 0.45). Among the 100 patients enrolled in this study, only twelve patients among the HF patients underwent coronary angiography.
Optimal medical therapy
All patients with HF could not receive goal-directed optimal medical therapy because of comorbidities and/or they could not tolerate it. Ninety-four percent of the patients received loop diuretics (furosemide or torsemide) at discharge. Aldosterone antagonist was prescribed in 78% of the patients. Fifty-seven percent of the patient received ACEI/ARB, while only 42% received beta-blockers. Sixty-three percent of the patients were getting digoxin, while only one patient received implantable cardioverter-defibrillator [Table 5].
| Discussion|| |
HF is a serious public health burden with patients having poor quality of life and shorter life expectancy compared to the general population. Due to an increasing life expectancy of the Nepalese population and comparatively progressive improvement in survival after acute myocardial infarction, it could be inevitable that HF will continue to be an important public health challenge in the near future. In our present study, 29% of the patients died in 3 months follow up period. Similar to our findings, a study reported 27% mortality in 90 days in ischemic HF patients. In another study from India, 8.5% in-hospital mortality was recorded in 90 days but did not provide data for overall mortality outside the hospital. In this study, HFpEF (≥45%) accounted for 26% of the total population. The high number of 3-month mortality in our study can be attributed to various reasons. HF patients of our study were very sick, as evidenced by advanced NYHA class at admission (93% at NYHA IV), higher mean LVEDD (59 mm) and higher creatinine, while lower hemoglobin level.
A large northern Europe observational study reported DCM as the cause of HF in 7.9% of patients admitted to the hospital. Whereas, recently in Nepal, Manandhar et al. reported DCM accounted for 50% of total HF cases reported. In agreement with above study from Nepal, even in our present study, the majority of the patients were considered idiopathic DCM (56%). The number of reported DCM cases was quite higher than in general. CAD is one of the main causes of HF worldwide.,,, Whereas in contrast to previous studies, the prevalence of CAD was low (18%) in the present study. Only 12% of the subjects among the total patients enrolled had undergone CAG in the current study. As the LVEF goes down, it is not easy to appreciate regional wall motion abnormalities in echocardiography, and ECG may remain inconclusive in the presence of triple vessel disease. Moreover, history alone is not sufficient for diagnosing CAD. This might have led to some underestimation of CAD in our study, but still, it is less compared to the western studies.,,, RHD accounted for 8% of total cases in the present study. However, Regmi et al. in 2009 reported that RHD was the major cause in HF patients, accounting for 45% of total cases. RHD is still common in the Nepalese population, but with much advancement in health facility since 2009, with better diagnostics and management, early medical attention and detection of subclinical carditis, and long-term anticoagulation therapy, a decreased risk of complication and overall mortality has been seen., Our results reported that alcohol abuse accounts for 12% of all HF patients. Alcohol use disorders have been on the rise in Nepal, with one in four/five men who consume alcohol are likely to have alcohol use disorders., Due to chronic alcohol abuse, there is an increase in blood pressure with weaker immune systems, which could lead to increased susceptibility to infections, which in turn could add to the development of HF. As our hospital is a high volume birth center, we found four patients with PPCM in such a short period. However, none of the etiology significantly correlated with mortality (P = 0.45). Our results are in contrast to Pocock et al., who reported that previous myocardial infarction, an ischaemic etiology of HF, was independent predictor mortality. The result of nonsignificant outcome on basis of the etiology could be due to a small sample size and shorter duration of follow up.
Arrhythmia is a common finding in HF. In fact, completely normal ECG virtually rules out HF. In this study, 17% of the participants had AF and 16% had conduction abnormity, mainly LBBB. Pericardial effusion was present in 11% of the patient. Mild MR was present in 34%, moderate in 34%, and severe MR in 6%. Previous studies have reported ischemic etiology of HF, AF, MR, and bundle branch block as a predictor of worse outcome., In our present study, none of the ECG and echocardiographic parameters except ejection fraction correlated positively with mortality.
In the present study, 55% of HF patients were >60 years of age, with 55 male and 45 female patients. Previous studies have reported advancing age, male sex, and lower LVEF as one of the most common predictors for HF death.,,,, However, in our present study though the number of death in males was numerically higher compared to females, it was not statistically significant. Similarly, advancing age was not significantly associated with mortality. Further studies are required with a larger number of a sample size to clarify the advancing age and male sex association with mortality in the Nepalese population. HF with systolic dysfunction is considered to have a poorer prognosis despite therapeutic advancement., The ECHOES mortality data reported poorer prognosis in HF patients with reduced LVEF compared to those with HF with normal LVEF. In agreement, our study also reported a high mortality rate in patients with reduced LVEF. Hobbs et al. reported a survival rate of 83% in those with EF 41%–50%, and 65% in those with <40%. Furthermore, in a large congestive HF population study, it reported an increase in 14% mortality rate for every 5% decrease in EF below 45%.
Studies have suggested that anemia increases the risk of CVD and mortality in chronic kidney disease or HF patients.,, Renal dysfunction is very common in HF patients. It is associated with high morbidity and mortality. Through multiple mechanisms, cardiac and renal dysfunction may worsen each other. Fluid overload, increased venous pressure, hypo-perfusion, neurohormonal or inflammatory activation, and concomitant treatment might be some of the underlying causes. In the current study, HF patients with mean hemoglobin < 12 g/dL and mean creatinine level more than 1.2 mg/dL at admission was significantly associated with increased mortality (P = 0.02). Our center observance to guideline-directed medical therapy with HF was in comparable to international studies guidelines.
The strength of the present study is it presents the real-world data of the region. It gives the outcome of 3-month follow-up of the HFrEF patients presenting in NYHA IV. One major limitation of the study is the lack of adequate coronary angiography. Many patients in the study labeled as idiopathic DCM may, in fact, be ischemic cardiomyopathy. Small sample size and inadequate therapy (lack of device therapy in eligible patients), and visually estimated LVEF are other limitations of the study.
| Conclusion|| |
DCM was the most common cause of acute decompensated HFrEF in the Nepalese population and had a very high 3-month mortality rate (29%). The presence of cardiovascular risk factors, such as hypertension and dyslipidemia, ejection fraction, hemoglobin, and creatinine level, was significant predictors of mortality in HFrEF patients. This study also highlights the importance of performing coronary angiography in Nepalese HFrEF patients for better etiological understanding.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3], [Table 4], [Table 5]