European Journal of Cardiovascular Medicine

Cardiovascular diseases (CVD) are a group of diseases that affect the heart and blood vessels, including coronary heart disease, cerebrovascular disease, arterial disease, rheumatic heart disease, congenital heart disease, deep venous thrombosis, and pulmonary embolism [1,2]. CVD is the leading cause of death in the world and the third leading cause of hospitalization in the public health system (SUS). The most frequent pathology of these hospitalizations is due to Heart Failure (HF) [3,4]. HF is a pathology where the heart muscle does not oxygenate and nurture the tissues properly. The etiology can differ among individuals, providing indirect or direct consequences in cardiac function and the cardiorespiratory system as a whole [5].

Cardiomyopathy is a primary disorder of the heart muscle that causes abnormal myocardial performance and is not the result of disease or dysfunction of other cardiac structures, systemic arterial hypertension, and valvular stenosis or regurgitation [6]. World Health Organization (WHO) and American Heart Association (AHA) classified cardiomyopathies into dilated, hypertrophic, and restrictive types depending upon the basic disturbance of the function [7,8]. Dilated cardiomyopathy (DCM) is characterized by cardiac enlargement and impaired systolic function of one or both ventricles. With increasing awareness of this condition along with improvement in diagnostic techniques, dilated cardiomyopathy is being recognized as a significant cause of morbidity and mortality. DCM is considered to be an important cause of heart failure and accounts for up to 25% of all cases of congestive heart failure [9]. The Framingham study has reported a 10% annual mortality rate for subjects having congestive cardiac failure [10]. Due to the increasing use of electrocardiogram (ECG) and echocardiography, the incidence of dilated cardiomyopathy is also showing a rising trend. It has become a topic of interest for physicians, cardiologists, cardiac surgeons, and many other groups of scientists.

Moreover, studies show that ECG and echocardiogram retain an extremely powerful role in the assessment of patients with dilated cardiomyopathy, which can provide diagnostic red flags useful to orient the following phases of the diagnostic work-up, prognostic stratification criteria, and information that can direct appropriate decision making. International guidelines state that both screenings are the most useful test in the diagnosis of HF structural abnormality, systolic dysfunction, diastolic dysfunction, or a combination of these abnormalities need to be documented in patients who present with resting or/and exertional symptoms to establish a definitive diagnosis. Hence, the present study was undertaken to study the clinical profile, electrocardiographic, and echocardiographic findings in patients with dilated cardiomyopathy.

Study Design and Setting

This prospective observational study was done over a period of one year in the Department of General Medicine of SVRRGGH, Tirupati. It was done in the Medical Wards and Intensive Care Units (AMC) of the hospital

Study Population and Sample Size

The population of the study admitted cases of dilated cardiomyopathy (DCM) to Medical Wards and Intensive Care Units. The study consisted of 60 cases, which were selected using a convenient sampling method.

Eligibility Criteria

Patients were included in the study on both clinical and echocardiographic reasons. Clinically, patients with signs and symptoms of heart failure were taken into consideration. Echocardiographic reasons were a left ventricular ejection fraction of less than 45%, global hypokinesia of the left ventricle, and dilation of all cardiac chambers. Patients providing written informed consent were included in the study. Patients with pericardial disease, peripartum cardiomyopathy, hypertrophic cardiomyopathy, restrictive cardiomyopathy, or congenital heart disease were excluded.

Ethical Concerns and Consent Ethical permission for the study was obtained from the Institutional Ethical Committee. Written informed consent was provided by all the participants agreeing to participate in the study.

Study Procedure

Patients who fulfilled the inclusion and exclusion criteria were enrolled in the study. A detailed clinical history was taken and a full physical examination was conducted. The findings were recorded on a pre-formatted proforma. All the patients underwent a panel of investigations, including 12-lead electrocardiogram (ECG), chest X-ray, and echocardiogram.

A 12-lead electrocardiogram was captured on the Mindray BeneHeart R3 Electrocardiograph. The ECG results were interpreted for any abnormalities. A posteroanterior chest X-ray was performed to assess the cardiothoracic ratio, pulmonary infiltrates, pulmonary plethora, and pleural effusion. Echocardiography was performed with the Esaote MyLab X6 Echo machine. Chamber sizes, ejection fraction, and global hypokinesia were assessed and interpreted accordingly.

Ischemic dilated cardiomyopathy was diagnosed either on the history of previous myocardial infarction or on the presence of >70% significant luminal occlusion on coronary angiography. Peripartum cardiomyopathy was diagnosed as per the criteria established by Demakis et al., i.e., onset of heart failure in the final month of pregnancy or within the first five months after delivery, lack of previous heart disease until the final month of pregnancy, echocardiographic demonstration of left ventricular dysfunction, and lack of other identifiable causes of heart failure.

Diabetic cardiomyopathy was also diagnosed in diabetic mellitus patients with over a ten-year history in whom no other definite reason for cardiomyopathy was present. Alcoholic cardiomyopathy was also diagnosed in patients with alcohol history (over ten years) with echocardiographic evidence of dilated cardiomyopathy with no other identifiable reason. If the etiology was not clear, the patient's case was termed idiopathic dilated cardiomyopathy.

Statistical Analysis

IBM SPSS Statistics software version 20 was used to analyze the data. Bar charts, pie charts, and frequency tables were used to present the findings. Mean and standard deviation were used to present continuous variables, while percentages and counts were used to present categorical variables. Chi-square test was used to analyze categorical variables. Parametric correlation analysis was performed using the Pearson correlation test, while the Spearman correlation test was used for non-parametric correlation. A p-value of < 0.05 was used as the cut-off for statistical significance.

Demographic Distribution

Age Distribution

The study population consisted of 60 patients who were diagnosed with dilated cardiomyopathy (DCM). Case distribution by age is shown in Table 1. Most of the patients (35%) were aged 50–59, followed by 32% in the >60 category. The 40–49 age group accounted for 23% of the population. Younger patients were affected less commonly, namely 7% aged between 19–29 and only 3% aged between 30–39. This age pattern indicates a greater burden of DCM among elderly persons since more than two-thirds of the cases were in the >50-year age group.

Table 1: Distribution of Cases Based on Age

Gender Distribution
As presented in Table 2, participants exhibited a large gender imbalance. Males represented 63% of the cases, while females represented 37%. This reveals a prominent male predominance in the occurrence of DCM.

Table 2: Distribution of Cases Based on Gender

Clinical Presentation

Symptomatology
The frequency of the symptoms seen among the study population has been shown in Table 3. Dyspnea was the most frequent symptom with 100% of patients reporting it. Easy fatigability was observed in 83% of the cases and pedal edema was observed in 70% of the patients. Palpitations, paroxysmal nocturnal dyspnea (PND), and cough were the other highly frequent symptoms seen (each in 60% of the patients). Orthopnea was described by 53%, whereas chest pain was described by 35%. The less frequent symptoms were abdominal pain (33%) and syncope (17%). There were no asymptomatic patients.

Table 3: Distribution of Cases Based on Symptomatology

Physical Examination Findings

Peripheral Pulse Characteristics
Table 4 depicts the classification of cases based on the nature of peripheral pulses. 44% of the cases had a reduced peripheral pulse, and 41% had a normal pulse. In addition, 15% of the respondents had irregular pulse rhythms.

Table 4: Distribution Based on Peripheral Pulse

Echocardiographic Findings

The echocardiography peripheral pulse assessment is outlined in Table 5. The group with decreased peripheral pulse had the lowest ejection fraction (EF) of 23% and also had elevated left ventricular end-diastolic (LVEDD) and end-systolic (LVESD) values.

Table 5: Echocardiographic Findings by Peripheral Pulse

NYHA Classification

The functional classification of the patients by the New York Heart Association (NYHA) system is demonstrated in Table 6. A total of 47% of the patients were NYHA Class IV, indicating severe heart failure.

Table 6: NYHA Classification

Electrocardiographic (ECG) Findings

ECG derangements were frequent, as shown in Table 7. The most common derangement was left axis deviation, occurring in 46% of the patients. Left ventricular hypertrophy was seen in 38%, and bundle branch blocks in 32% of the patients.

Table 7: ECG Features in DCM Patients

Alcohol Intake and DCM

The association between alcohol intake and DCM is summarized in Table 8. Alcoholic DCM was observed in 9 cases (15%), while non-alcoholic DCM accounted for 51 cases (85%).

Table 8: Distribution Based on Alcohol Intake

Results of this study highlight that dilated cardiomyopathy predominantly occurs in the elderly with a male predominance. Dyspnea, fatigue on minimal exertion, and pedal edema were the presenting features in most. Echocardiographic findings revealed extensive left ventricular dysfunction with low ejection fractions. Alcoholic cardiomyopathy was less prevalent compared to non-alcoholic types. These results provide an insight regarding the demographic, clinical, and echocardiographic features of DCM in the studied population.

Patient data analysis gives interesting information about the demographic and clinical profile of dilated cardiomyopathy (DCM) diagnosed individuals. The distribution by age shows that more than half of the patients are above 50 years, and 35% fall in the 50-59 age category and 32% are older than 60. This correlates with the experience of the Framingham Heart Study, which reported a higher occurrence of congestive heart failure (CHF) in older subjects. The gender ratio suggests a male predominance (63%) over females (37%), and higher prevalence of DCM in men, a finding consistent with earlier studies that have shown a greater occurrence of heart failure in men than in women.

Analysis of symptomatology reveals that all the patients had dyspnea, with a very high percentage stating easy fatigability (83%), pedal edema (70%), and palpitations (60%). These findings are in accordance with clinical presentation that is most commonly described in the literature with DCM. The clinical findings on physical examination are also consistent with the diagnosis, including basal crackles heard in 93% of patients, elevated jugular venous pressure (73%), and pedal edema (77%). These findings point towards fluid overload and impaired cardiac function, characteristic of heart failure [11].

Electrocardiographic (ECG) findings show that left axis deviation was found in 46% of the patients and left ventricular hypertrophy (LVH) in 38%. Bundle branch blocks were found in 32% of the cases, the left bundle branch block (LBBB) being more prevalent (15%) than right bundle branch block (RBBB) (5%). Such ECG changes agree with the electrical conduction defects often encountered in DCM patients [12].

Echocardiographic findings reveal severe structural and functional abnormalities of the heart. Enlargement of the left atrium was seen in 54% of the patients, right ventricular enlargement in 40%, and diastolic dysfunction in 42%. Valvular regurgitation was seen in 64% of the cases, with mitral regurgitation being the commonest. These echocardiographic abnormalities are typical of DCM and are responsible for the clinical syndrome of heart failure. The average ejection fraction (EF) was significantly low at 28.6%, indicating extreme systolic dysfunction. This is consistent with prior research emphasizing low EF as a predictive factor in heart failure patients [13].

Functional grading based on the New York Heart Association (NYHA) showed that 47% of patients were Class IV, meaning they had severe limitations. Such a distribution emphasizes the advanced stage of disease in a high percentage of the population. In comparison, the Framingham Heart Study had found a median survival following the development of CHF of 1.7 years in men and 3.2 years in women, which indicates the poor prognosis that can accompany advanced heart failure [14].

For alcohol use, 15% of the patients were diagnosed with alcoholic DCM and the other 85% had non-alcoholic DCM. This highlights the contribution of alcohol consumption to the etiology of DCM, in line with earlier studies that have demonstrated a correlation between chronic alcohol use and the pathogenesis of cardiomyopathy [15].

In summary, the patient data is a mirror of the demographic and clinical trends seen in DCM, with a prevalence that is more in elderly and men, and also with clinical presentation of high symptoms and structural cardiac defects. All of these concord with established literature and highlight the need for early detection and treatment in order to enhance patient outcomes.

In conclusion, the present study identifies the heavy toll of dilated cardiomyopathy (DCM), which occurs mainly in the elderly with increased prevalence in men. The clinical presentation is characterized by severe symptoms such as dyspnea, easy fatigability, and pedal edema, with extensive functional impairment evidenced by the large number of NYHA Class III and IV cases. Echocardiographic results show significant structural and functional cardiac derangements, particularly left ventricular dilatation and decreased ejection fraction, that are most predictive of poor outcome. The correlation with alcohol consumption in a subgroup of patients highlights its status as a modifiable risk factor. These results are in line with earlier research, including the Framingham Heart Study, and highlight the importance of early diagnosis and overall management approaches to enhance DCM patient outcomes.

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