Atrial fibrillation (AF) is a common supraventricular tachyarrhythmia affecting 1% to 2% of the general population.[1] The risk of AF generally increases with aging, hypertension, coronary artery disease, diabetes mellitus, alcohol use.[2,3] However, the valvular disease is the most common substrate for AF in areas with a high prevalence of rheumatic heart disease and is a risk factor for embolic stroke and heart failure.[4,5]

The cardiac remodeling that occurs in response to various causes tends to increase the left atrial pressure and size and alter wall stress creating a substrate to cause AF.[6,7,8] The enlarged left atrium (LA) has been correlated with AF occurrence and cardiovascular events.[9,10] The left ventricular ejection fraction (LVEF) is also associated with AF development and its consequences.[11,12]

Atrial fibrillation (AF) is the most common sustained cardiac arrhythmia worldwide, resulting from chaotic atrial electrical impulses that lead to loss of coordinated atrial contraction. It contributes substantially to cardiovascular morbidity and mortality by increasing the risk of stroke, heart failure, and all-cause death. The prevalence of AF rises with age and the presence of comorbid conditions such as hypertension, valvular heart disease, diabetes, and ischemic heart disease. Echocardiography serves as an invaluable diagnostic tool to evaluate structural and functional cardiac abnormalities, including chamber enlargement, valvular lesions, and ventricular dysfunction. Assessing the clinical profile and echocardiographic findings in patients with AF provides critical insights into underlying etiologies, disease severity, and guides individualized management strategies aimed at improving outcomes and reducing complications.

The aim of the present study is to determine the clinical profile and echocardiographic abnormalities in patients of AF in Indian perspective. It will help in better management and diagnosis of patients with atrial fibrillation.

Study Area: Outdoor and indoor patients of department of Cardiology Medical College and Hospital, Kolkata.

Study Population:

Consecutive adult patients in the outdoor diagnosed as Atrial fibrillation by surface electrocardiogram. Cases are defined as adult patients with a diagnosis of atrial fibrillation.

It was diagnosed clinically by the presence of irregularly irregular pulse rate, pulse deficit of >10, S1 of variable intensity and by using 12 Lead ECG showing absence of P waves, presence of fibrillatory waves that vary in size, shape and timing leading to irregular ventricular response.

Inclusion Criteria:

All case patients as defined.

Exclusion Criteria:

Patients <= 18 years age.

Patients suspected clinically to have atrial fibrillation later proved to have different arrhythmia electrocardiographically were excluded from this study.

Study Period:

One year (January 2022 – December 2022)

Sample Size: 1000

Study Design: Hospital based cross sectional study.

Statistical Analysis: -  

For statistical analysis, data were initially entered into a Microsoft Excel spreadsheet and then analyzed using SPSS (version 27.0; SPSS Inc., Chicago, IL, USA) and GraphPad Prism (version 5). Numerical variables were summarized using means and standard deviations, while Data were entered into Excel and analyzed using SPSS and GraphPad Prism. Numerical variables were summarized using means and standard deviations, while categorical variables were described with counts and percentages. Two-sample t-tests were used to compare independent groups, while paired t-tests accounted for correlations in paired data. Chi-square tests (including Fisher’s exact test for small sample sizes) were used for categorical data comparisons. P-values ≤ 0.05 were considered statistically significant

Table 1: Comparison Of Demographic Characteristics Between Valvular And Non-Valvular Atrial Fibrillation

Table 2: Distribution Of Study Subjects as Per Type of Atrial Fibrillation

Table 3: Comparison Of Type of Treatment Between Af Groups

Table 4: Comparison Of Chad-Vasc Score Between Afgroups

Figure 1: Comparison Of Heart Disease Between AF groups

Figure 2: Comparison Of Symptoms Between Valvular And Non-Valvular AF

In the present study, a total of 471 patients with atrial fibrillation were analyzed, comprising 395 (83.9%) cases of non-valvular AF and 76 (16.1%) cases of valvular AF. Among non-valvular AF patients, males predominated with 257 cases (65.1%) compared to 138 females (34.9%). In contrast, valvular AF showed a reverse pattern, with females being significantly higher at 45 cases (59.2%) compared to 31 males (40.8%). The overall distribution indicated that 288 patients (61.1%) were male and 183 (38.9%) were female. The difference in gender distribution between valvular and non-valvular AF was found to be statistically highly significant (P < 0.001).

The mean age of the study population was 58.7 ± 14.9 years, with a median age of 59 years (IQR 47–69) and an overall age range of 27 to 90 years. Patients with non-valvular atrial fibrillation (AF) were significantly older, with a mean age of 61.6 ± 14.0 years and a median of 63 years (IQR 51–71), compared to those with valvular AF, who had a mean age of 43.7 ± 9.1 years and a median of 41.5 years (IQR 35.5–53). This indicates that non-valvular AF predominantly affected an older population, while valvular AF was more common among younger patients. The difference in age distribution between the two groups was statistically highly significant (P < 0.001).

The mean body mass index (BMI) of the total study population was 23.6 ± 2.2 kg/m², with a median of 24.1 kg/m² (IQR 21.8–25.3) and a range of 18.3–27.4 kg/m². Patients with non-valvular atrial fibrillation (AF) had a higher mean BMI of 24.0 ± 2.1 kg/m² and a median of 24.4 kg/m² (IQR 22.8–25.6), whereas those with valvular AF had a lower mean BMI of 21.4 ± 1.8 kg/m² and a median of 21.6 kg/m² (IQR 20.0–22.7). This indicates that patients with non-valvular AF were relatively more overweight compared to those with valvular AF. The difference in BMI between the two groups was found to be statistically highly significant (P < 0.001).

In the present study comprising 471 patients with atrial fibrillation, the majority of cases were of the persistent type, accounting for 410 patients (87%), while paroxysmal atrial fibrillation was observed in 61 patients (13%). This indicates that persistent atrial fibrillation was the predominant form encountered in the study population.

In the present study, out of 471 patients with atrial fibrillation, 61 (13%) had paroxysmal AF and 410 (87%) had persistent AF. Among patients with paroxysmal AF, 36 (59.0%) received rhythm control therapy, 23 (37.7%) were managed with rate control, and 2 (3.3%) did not require specific treatment. In contrast, among those with persistent AF, the majority—375 patients (91.5%)—were managed with rate control, 30 (7.3%) received rhythm control therapy, and 5 (1.2%) required no treatment. The difference in treatment approach between paroxysmal and persistent AF was statistically highly significant (P < 0.001), indicating that rhythm control was more commonly used in paroxysmal AF, whereas rate control predominated in persistent AF.

In the present study, the mean CHAD-VASc score among patients with atrial fibrillation was 2.1 ± 1.5, with a median of 2.0 (IQR 1.0–3.0) and a range of 0–6. Patients with paroxysmal atrial fibrillation had a lower mean CHAD-VASc score of 0.9 ± 1.0 and a median of 0.0 (IQR 0.0–2.0), whereas those with persistent atrial fibrillation had a significantly higher mean score of 2.3 ± 1.4 and a median of 2.0 (IQR 1.0–3.0). The difference in CHAD-VASc scores between paroxysmal and persistent AF patients was statistically highly significant (P < 0.001), indicating a greater burden of comorbidities and higher thromboembolic risk in patients with persistent atrial fibrillation.

Majority of Paroxysmal AF group (34, 55.7%) had structurally normal heart whereas only a few of the Persistent AF group (30, 7.3%) had structurally normal heart. Commonest structural defects in Paroxysmal AF group were hypertensive heart disease (17, 27.9%) and post-operative defects (8 ,13.1%). Whereas commonest structural defects in Persistent AF group were hypertensive heart disease (128, 31.2%), Ischemic heart disease (75, 18.4%) and Rheumatic Mitral Stenosis (68, 16.7%). This differential pattern was statistically significant.

None of them were asymptomatic in valvular AF whereas few (13.7%) were asymptomatic in non-valvular AF. Commonest symptom in Valvular AF group was Dyspnoea (70, 92.1%) whereas commonest symptom in non valvular group was palpitation (161, 40.8%). This differential finding was statistically significant.

In the present study, gender distribution showed a significant difference between valvular and non-valvular atrial fibrillation (AF) groups (P < 0.001). Among 471 patients, non-valvular AF accounted for 395 (83.9%) cases, where males predominated with 257 (65.1%) compared to 138 females (34.9%). Conversely, in the valvular AF group (76 patients, 16.1%), females were more affected, constituting 45 (59.2%) cases, while males comprised 31 (40.8%). This pattern suggests that non-valvular AF is more prevalent among males, whereas valvular AF is more common among females, possibly due to the higher incidence of rheumatic valvular disease in women.

In the present study, the mean age of patients with atrial fibrillation was 58.7 ± 14.9 years, ranging from 27 to 90 years, indicating that AF commonly affected middle-aged and elderly individuals. Patients with non-valvular AF were significantly older, with a mean age of 61.6 ± 14.0 years, compared to valvular AF patients, whose mean age was 43.7 ± 9.1 years (P < 0.001). This difference highlights that non-valvular AF predominantly occurs in the older population, possibly due to degenerative and ischemic cardiac changes, while valvular AF tends to affect younger individuals, likely reflecting the influence of rheumatic valvular disease in this age group.

In the present study, the mean BMI of the overall atrial fibrillation population was 23.6 ± 2.2 kg/m², indicating that most patients were within the normal to overweight range. Patients with non-valvular AF had a significantly higher mean BMI of 24.0 ± 2.1 kg/m² compared to 21.4 ± 1.8 kg/m² in those with valvular AF (P < 0.001). This finding suggests that obesity and higher body mass index are more strongly associated with non-valvular AF, likely due to the link between increased adiposity, hypertension, and structural cardiac remodeling. In contrast, valvular AF occurred more frequently in leaner individuals, often secondary to rheumatic or structural valvular heart disease.

In the present study, persistent atrial fibrillation (AF) was the most prevalent type, observed in 410 patients (87%), while paroxysmal AF was seen in 61 patients (13%). The predominance of persistent AF suggests a higher burden of chronic or advanced cardiac disease among the study population. This finding aligns with existing literature indicating that persistent AF is more common in patients with structural heart abnormalities, hypertension, and advancing age. The lower frequency of paroxysmal AF may reflect delayed diagnosis or progression of intermittent AF to a sustained form due to inadequate early management or underlying comorbidities.

In the present study, treatment patterns differed significantly between paroxysmal and persistent atrial fibrillation (AF) (P < 0.001). Among the 61 patients with paroxysmal AF, rhythm control therapy was preferred in 36 cases (59.0%), while 23 (37.7%) received rate control and 2 (3.3%) required no treatment. Conversely, in the 410 patients with persistent AF, the majority—375 (91.5%)—were managed with rate control, 30 (7.3%) received rhythm control, and 5 (1.2%) required no specific therapy. This trend highlights that rhythm control is typically favored for paroxysmal AF to restore and maintain sinus rhythm, whereas rate control remains the mainstay in persistent AF to manage ventricular response and improve symptom control.

In the present study, a significant difference was observed in CHAD-VASc scores between paroxysmal and persistent atrial fibrillation (AF) (P < 0.001). The mean CHAD-VASc score of the total population was 2.1 ± 1.5, reflecting a moderate risk of thromboembolism. Patients with paroxysmal AF had a lower mean score of 0.9 ± 1.0, indicating fewer associated risk factors, while those with persistent AF had a higher mean score of 2.3 ± 1.4, suggesting a greater burden of comorbid conditions such as hypertension, diabetes, and structural heart disease. This significant difference underscores that persistent AF is associated with higher stroke risk and emphasizes the need for more aggressive anticoagulation and risk factor management in these patients.

In the present study, structural heart abnormalities showed a statistically significant difference between paroxysmal and persistent atrial fibrillation (AF) groups. A majority of patients with paroxysmal AF (34, 55.7%) had structurally normal hearts, whereas only 30 patients (7.3%) in the persistent AF group had no structural abnormalities. Among paroxysmal AF patients, the most common structural defects were hypertensive heart disease (17, 27.9%) and postoperative defects (8, 13.1%). In contrast, persistent AF was predominantly associated with hypertensive heart disease (128, 31.2%), ischemic heart disease (75, 18.4%), and rheumatic mitral stenosis (68, 16.7%). This pattern indicates that persistent AF is more frequently linked to significant structural and valvular heart disease, while paroxysmal AF often occurs in structurally normal hearts or with mild cardiac abnormalities.

In the present study, symptom distribution showed a statistically significant difference between valvular and non-valvular atrial fibrillation (AF) groups. None of the patients with valvular AF were asymptomatic, while 13.7% of those with non-valvular AF had no symptoms. The most common presenting symptom among valvular AF patients was dyspnoea, observed in 70 cases (92.1%), reflecting the underlying hemodynamic burden of valvular disease. In contrast, palpitation was the predominant symptom in the non-valvular AF group, reported by 161 patients (40.8%). This finding suggests that valvular AF is more likely to manifest with heart failure–related symptoms, whereas non-valvular AF often presents with awareness of irregular heartbeat or milder symptoms.

We concluded that, a comprehensive evaluation of patients with atrial fibrillation (AF) revealed distinct clinical and echocardiographic patterns between valvular and non-valvular types. Non-valvular AF was more common, particularly among older males, and was frequently associated with higher BMI and comorbidities such as hypertension and ischemic heart disease. In contrast, valvular AF predominantly affected younger females, with rheumatic mitral stenosis being the most frequent underlying cause. Persistent AF was the predominant form, associated with higher CHAD-VASc scores and greater structural abnormalities on echocardiography. Dyspnoea was the leading symptom in valvular AF, while palpitations were common in non-valvular AF. Rhythm control was preferred in paroxysmal AF, whereas rate control dominated in persistent AF. These findings highlight the importance of early detection, echocardiographic evaluation, and individualized management strategies to prevent complications such as heart failure and thromboembolism, thereby improving outcomes in patients with atrial fibrillation.

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