Atrial fibrillation (AF) is a supraventricular tachyarrhythmia with uncoordinated atrial electrical activation and consequent ineffective atrial contraction [1] . By substituting disordered electrical activity for regular sinus pulses, AF has haemodynamic consequences, with a loss of atrial contribution to cardiac output and an increased risk of thromboembolic events [2] . It can be complicated by stroke and heart failure [3] .

AF and HF share common pathophysiological features (4). The association of AF and CHF is explained by common risk factors such as age, arterial hypertension (AH), diabetes, obesity, as well as valvular, ischaemic or hypertrophic heart disease, and even hyperthyroidism [4] . Its management focuses on thromboembolic prevention, ventricular rate control, maintenance of sinus rhythm and management of risk factors and co-morbidities [5] . Epidemiologically, AF is the most common cardiac arrhythmia, affecting 1 to 2% of the general population [6] . It is the most common sustained arrhythmia in heart failure, with an average prevalence of 25% [7] . CHF and AF have emerged as two new epidemics of cardiovascular disease over the last 20 years. The prevalence of both conditions is expected to increase as the population ages. By 2030, there will be 12 million Americans with AF and more than 8 million with IC [8] .

The results of the NATURE HF registry show that among the 2040 heart failure patients, 337 with an average age of 65 ± 13 years had AF (16.5%) [9] .

In sub-Saharan Africa, a major cause of AF is rheumatic disease [10] .

The VALVAFRIC study carried out in 7 countries in West and Central Africa found that 22% of the 3441 patients with rheumatic valve disease had AF [11] .

In Senegal in 2023, AFFANGLA DA found 47.76% heart failure in patients suffering from atrial fibrillation [12] .

The aim of this study was to investigate the sociodemographic, diagnostic and therapeutic aspects of AF in patients hospitalised for IC in the cardiology department of the Ignace Deen University Hospital.

During the study period, 372 patients were hospitalised for heart failure, 98 of whom had atrial fibrillation, a rate of 26.3%. The mean age of the patients was 56.47 ± 20.37 years. The 60 - 74 age group was the most represented (30.6%). The majority of patients were female (59%) with a sex ratio M/F of 0.6. The majority of our patients had a primary school education (57.1%) ( Table 1 ). Age (53.1%) and arterial hypertension (44.9%) were the risk factors most frequently encountered in our study. A history of heart disease and atrial fibrillation were found in 36.7% and 30.6% respectively ( Table 2 ).

Dyspnoea was the main reason for consultation (85.7%), followed by palpitations (63.7%). NYHA class III was the most common (42.8%) ( Table 3 ). ECG abnormalities were dominated by left ventricular hypertrophy (38.7% of cases). The mean ventricular rate was 116 bpm ± 30.24 with extremes of 100 and 165. Permanent AF was predominant in 70% of our patients, persistent AF in 26% and paroxysmal AF in 4% ( Table 4 ). Dilatation of the left ear was predominant on TTE, accounting for 79.6% of cases. Underlying heart disease was dominated by rheumatic valve disease (48.9%), followed by hypertensive heart disease (22.4%) ( Table 5 ). The strategy of frequency control was the main objective in all our patients, beta-blockers were used in 81.6% of our patients followed by Digoxin in 29.5% of cases. Direct oral anticoagulants (DOACs) were used in 48% of our patients. Furosemide was prescribed in 94 patients (96%), Aldactone in 71%, ACE inhibitors in 57%, and inotropes and ARAII in 2% each ( Table 6 ).

Other: Cough, Tinnitus, epigastralgia, dizziness.

LAH: Left atrial hypertrophy, RAH: right atrial hypertrophy, LVH: left ventricular hypertrophy, RVH: right ventricular hypertrophy. AHR: average heart rate.

AF and heart failure have a complex, bidirectional relationship. AF aggravates heart failure, leading to a significant increase in symptoms, hospitalisations and cardiovascular mortality. These two conditions, which are constantly on the increase due to the ageing of the population, represent a major public health issue [13] . Both conditions have become epidemics of the 21st century, and prevalence continues to rise as a result of increased longevity and the successful reduction of cardiovascular (CV) mortality, significantly increasing the cost of treatment for healthcare systems worldwide [13] .

Our study of 98 patients at Ignace Deen University Hospital illustrates this reality. However, the constraints associated with an unfavourable socio-economic context, such as limited access to certain complementary examinations, limited our study. Despite these constraints, our results highlight the importance of this issue.

During our survey period, 372 patients were admitted to the department for heart failure, 98 of whom had atrial fibrillation, a frequency of 26.34%. This proportion is lower than the results reported in other studies, such as those by DIOP KR et al. [3] (66%) or Parag Goyal et al. [14] (40%). In the Framingham Heart Study, AF occurred in more than half of people with CHF, and CHF occurred in more than a third of people with AF [15] . This difference with our study could be explained by the difference in sample size, the study conditions and the means used to screen for AF in IC patients. It should be remembered that in Guinea AF is under-diagnosed, paroxysmal or asymptomatic AF is often unrecognised because only symptomatic and severe forms are referred to cardiology.

The mean age of our patients (56.47 years) was comparable to that reported in other African studies by SANGARE I et al. [16] and DIOP KR et al. [3] , but lower than the average observed in western countries (70 - 80 years). This difference could be explained by the higher prevalence of rheumatic valve disease in sub-Saharan Africa, which often affects younger populations [17] . Nevertheless, our results suggest a trend towards an increase in the mean age of patients with atrial fibrillation in Africa.

Our study revealed a predominance of females (59%), a result in agreement with the work of DIOP KR et al. [3] and SANGARE I et al. [16] . However, Samoura Aly et al. [18] reported a male predominance in their study of hypertensive patients. With regard to level of education, our results, similar to those of DIOP KR et al. [3] , show a majority of patients with primary education. Age and hypertension were the main risk factors identified in our study (53.1% and 42.9%), in line with the literature [19] [20] . A history of heart disease (36.7%) and diabetes (14.3%) were also common. These results confirm the importance of hypertension, diabetes, cardiovascular disease and age in the development of atrial fibrillation, as highlighted in previous studies [19] [20] . The main reasons for consultation in our study were dyspnoea (85.7%), palpitations (67.3%) and oedema of the lower limbs (44.9%). These results are comparable to those reported by DIOP KR et al. [3] and SANGARE I et al. [16] , where heart failure was the most frequent reason for consultation. These results could be explained by the fact that dyspnoea, a frequent symptom of heart failure, is often the main reason why patients consult their doctor.

With regard to NYHA classification, stage III was the most frequent in our cohort (42.8%), a result similar to that reported by Camara A et al. [21] . However, unlike that study, stage II was the second most common stage in our patients (30.6%). The difference in the study population could explain this result. The predominance of stage III suggests that our patients consult specialist facilities late.

We observed a predominance of permanent atrial fibrillation (70%) in our patients, followed by persistent AF (26%) and paroxysmal AF (4%). This distribution is in line with data from the African literature, where permanent AF is more frequently reported [3] . This difference can be explained by the high prevalence of valvular heart disease in sub-Saharan Africa and by later diagnosis, which favours progression to more chronic forms of AF.

Echocardiography revealed left atrial dilatation in 76.6% of our patients, a rate comparable to those reported by SANGARE I et al. [16] (42.31%) and Samoura A et al. [18] (95.92%). (20) and Samoura A et al. [18] (95.92%) (This association between AF and left atrial dilatation is well known. We also observed left (42.8%) and right (38.8%) ventricular dilatation, which could be explained by the prevalence of valvulopathy in our population.

We observed that 51% of cases had preserved LVEF. SANGARE I et al. [16] described left ventricular (LV) systolic dysfunction in 36.54% of cases. Studies in Korea and Sweden have shown that the prevalence of AF increases significantly in heart failure patients with preserved LVEF [15] , which could be explained by earlier detection and the ageing of the population in these regions. Furthermore, LVEF may remain preserved for a long time in patients with valvular heart disease, which could partly explain our results.

The predominance of rheumatic valve disease (48.97%) among the causes of atrial fibrillation (AF) in our cohort is characteristic of sub-Saharan African populations [3] [16] , where sequelae of rheumatic fever are still common. This observation contrasts with data from the international literature, where ischaemic heart disease and arterial hypertension are more often associated with AF [15] . These differences can be explained by socio-economic factors, lifestyle habits and variable access to healthcare in different regions.

Our study favoured a strategy of heart rate control in all patients, with the majority using beta-blockers (81.6%). This approach is in line with international recommendations [22] [23] and current practice in Africa, as shown by the work of DIOP KR et al. [3] (78%) (3) and SANGARE I et al. [16] (50%). The choice of frequency control rather than rhythm control is explained by the often late diagnosis, which limits the therapeutic options.

All our patients had a high thromboembolic risk (CHA2DS2-VASc ≥ 2) and received oral anticoagulation. AODs were the treatment of choice in 48% of patients, followed by VKAs (40%). This strategy is in line with international recommendations [22] [24] , which favour OADs because of their favourable benefit-risk profile. Our results differ from those reported in other African studies [3] [16] where VKAs were more frequently used. This evolution suggests a gradual adoption of AODs, despite their higher cost, particularly in patients with the means to obtain them.

The predominant use of diuretics, particularly furosemide, is justified by their essential role in managing congestion and facilitating heart rate control in patients suffering from both heart failure and atrial fibrillation.

Systematic screening during consultations could prevent the onset of heart failure, particularly of rhythmic origin.

Atrial fibrillation and heart failure represent a double burden for public health in Guinea, with significant consequences for morbidity and mortality. AF, which is particularly common in patients with rheumatic heart disease, is often under-diagnosed and more likely to be permanent. Although heart rate control is the preferred therapeutic strategy, access to anticoagulant treatments, particularly AODs, remains limited for some patients due to their cost. Despite this, AODs are becoming more widely available in clinical practice. The prevalence of AF in a young population with little education highlights the importance of setting up prevention and early detection programmes, targeting at-risk populations in particular.