Right atrial enlargement

Right atrial enlargement
Right atrial enlargement
Other names	Right atrium enlargement
	Right atrial enlargement (P pulmonale)
Causes	Pulmonary Hypertension
Diagnostic method	electrocardiogram

Right atrial enlargement (RAE) is a form of cardiomegaly, or heart enlargement. It can broadly be classified as either right atrial hypertrophy (RAH), overgrowth, or dilation, like an expanding balloon. Common causes include pulmonary hypertension, which can be the primary defect leading to RAE, or pulmonary hypertension secondary to tricuspid stenosis; pulmonary stenosis or Tetralogy of Fallot i.e. congenital diseases; chronic lung disease, such as cor pulmonale. Other recognised causes are: right ventricular failure, tricuspid regurgitation, and atrial septal defect.^[1] Right atrial enlargement (RAE) is clinically significant due to its prevalence in diagnosing supraventricular arrhythmias. Further, early diagnosis using risk factors like RAE may decrease mortality because patients with RAE are at 9x more risk of arrhythmias and other cardiac conditions compared to their healthy counterparts.^[2]

Signs and symptoms

Symptoms of right atrial enlargement include palpitations, dyspnea, paroxysmal tachycardia, general malaise, shortness of breath, syncope, chest pain, fatigue, cyanosis, loss of appetite, tachycardia, fever, and cough. Many patients with right atrial enlargement are asymptomatic.^[3]

Causes

Most authors have classified this condition as congenital, but the etiology is still unknown.^[3]

Diagnosis

Right Atrial Enlargement (RAE) increases the p wave, representing atrial depolarization, on an ECG to an amplitude > 2.5mm in lead II, an abnormality referred to as p-pulmonale, likely due to weakened right atrial myocardium close to the Sinoatrial (SA) node.^[4]

ECG criteria for RAE: P wave amplitude in lead II > 2.5 mm and upward deflection of the P wave in lead V1 > 1.5 mm in amplitude.^[5]

Large "a" waves on the JVP waveform can also aid in diagnosis.

References

^ "Size of the right atrium and associated structures". 123 sonography.com. Medical University of Vienna. 2012-08-20. Retrieved 13 December 2016.
^ Ho, A.K.; Low, G.; Zhang, Yi; Le, Lawrence H.; Minosse, Silvia; Vidiri, Antonello; Zheng, Rui; Lou, Edmond; Edam, A.N.; Bradley, D.A.; Nguyen, Vu-Hieu; Le, Lawrence H. (May 1, 2018). "Right atrium enlargement predicts clinically significant supraventricular arrhythmia in patients with pulmonary arterial hypertension". Heart & Lung. 47 (3). Mosby: 237–242. doi:10.1016/j.hrtlng.2018.01.004. ISSN 0147-9563. S2CID 3363049. Retrieved December 29, 2023.
^ ^a ^b Terada, Tadashi; Oiwake, Hisanori; Nakanuma, Yasuni; Ohta, Goroku; Nishino, Tomoichi (1988). "An Autopsy Case of Idiopathic Enlargement of the Right Atrium, and a Review of the Literature". Pathology International. 38 (3): 361–370. doi:10.1111/j.1440-1827.1988.tb02308.x. ISSN 1320-5463. PMID 2969171. S2CID 41759734.
^ G, Limongelli; D, Masarone; G, Frisso; M, Iacomino; I, Ferrara; A, Rea; R, Gravino; E, Bossone; F, Salvatore; R, Calabro; P, Elliott; G, Pacileo (2017). "Clinical and genetic characterization of patients with hypertrophic cardiomyopathy and right atrial enlargement". Journal of Cardiovascular Medicine (Hagerstown, Md.). 18 (4). J Cardiovasc Med (Hagerstown): 249–254. doi:10.2459/JCM.0000000000000361. ISSN 1558-2035. PMID 26808413. S2CID 25505222. Retrieved December 29, 2023.
^ Surawicz, Borys; Childers, Rory; Deal, Barbara J.; Gettes, Leonard S. (2009). "AHA/ACCF/HRS Recommendations for the Standardization and Interpretation of the Electrocardiogram". Circulation. 119 (10): e235-40. doi:10.1161/circulationaha.108.191095. PMID 19228822. S2CID 26702140.