PII S0894 7317(97)70027 0 Atrial Septal Aneurysm A N e w Classification in Two Hundred Five Adults Alexander Olivares Reyes, MD, Samuel Chan, MD, Eliot J Lazar, MD, Kishore Bandlamudi, RDCS, Venkatesw.
Atrial Septal Aneurysm: A N e w Classification in T w o Hundred Five Adults Alexander Olivares-Reyes, MD, Samuel Chan, MD, Eliot J Lazar, MD, Kishore Bandlamudi, RDCS, Venkateswara Narla, MD, and Kenneth Ong, MD, Brooklyn, New York Atrial septal aneurysm is a localized "saccular" deformity, generally at the level Of the fossa ovalis, which protrudes to the right or the left atrium or both For 39 months we prospectively analyzed 205 consecutive patients in whom atrial septal aneurysm was diagnosed echocardiographically The direction and movement of atrial septal aneurysms were carefully studied in multiple views, and, according to our findings, we now propose a new classification: type 1R if the bulging is in the right atrium only, type 2L if the bulging is in the left atrium only, type 3RL if the major excursion bulges to the right atrium and the lesser excursion bulges toward the left, type L R if the maximal excursion of the atrial septal aneurysm is toward the left atrium with a lesser excursion toward the right atrium, type if the atrial septal aneurysm movement is bidirectional and equidistant to both atria during the cardiorespiratory cycle We found an incidence of 1.9%, a mean age of 63 Atrial septal aneurysm (ASA) is a localized "saccular" deformity o f the interatrial septum, generally at the level o f the fossa ovalis, which bulges into the right or left atrium or both However, this definition o f ASA is arbitrary ASA was initially t h o u g h t to be a rare congenital abnormality, but, with the advent of two-dimensional echocardiography and, more recently, the widespread use o f transesophageal echocardiography (TEE), it has become more easily and more frequently identified in patients 2,s Prevalence The prevalence o f ASA varies, but transthoracic echocardiographic (TTE) studies estimate the rate to be between 0.08% and 1.2% 4-13 In a large autopsy series the prevalence reported was 1% ~ More recent studies with T E E have shown a prevalence between 2% and ].0% 6'12'14-16 In the pediatric patient population, the From the Echocardiography Laboratory, Cardiology Division, Department of Internal Medicine of The Brooklyn Hospital Center Reprint requests: AlexanderOlivares-Reyes,MD, 42-37 Hampton St., Suite No 2F, Elmhurst, New York, NY 11373 Copyright © 1997 by the American Sodety of Echoeardiography 0894-7317/97 $5.00+ 27/1/80030 644 years (25 to 97 years), a female/male ratio of 2:1, valvular regurgitation 74%, hypertension 64%, left ventricular hypertrophy 38%, coronary heart disease 32%, patent foramen ovale 32%, pulmonary hypertension 31%, stroke 20%, dysrhythmias 16%, valvular prolapse 15%, and atrial septal defect 3% No differences were found between mobile and motionless types of atrial septal aneurysm However, differences were found between predominantly left bulging or right bulging atrial septal aneurysm (134 versus 57 patients), as well as other variables All types of atrial septal aneurysm have particular clinical or echocardiographic characteristics The new classification is a complete, simple, and practical form Atrial septal aneurysm is associated with congenital and acquired heart diseases but also can present as an isolated abnormality (J Am Soc Echocardiogr 1997;10:644-56.) prevalence reported by T T E is 0.9% to 1.7% in children and 4.9% in infants 17-19 ASA Association ASA has been associated with congcnital heart diseases such as patent foramen ovale (PFO), atrial septal defects (ASD), ventricular septal defects, valvular prolapse, patent ductus arteriosus, Ebstein's anomaly, and tricuspid and pulmonary atresia,* as well as acquired heart diseases including valvular disease, cardiomyopathy, systemic and pulmonary hypertension, ischemic heart disease, arrhythmias, and thrombus formation.¢ More recently a n u m b e r o f studies found an association between ASA and cerebrovascular events (CVE) o f embolic origin, including transient ischemic attacks (TIA) and cerebrovascular accidents (CVA).* ASA Classification In 1985 Longhini ct al.10 reported on 23 patients with ASA diagnosed with M - m o d e and two-dimen- *References 2, 4, 8, 9, 11, 12, 16-40 eReferences 6-10, 23, 26, 35, 36, 41, 42 *References 6~9, 12, 14q6, 21-25, 34-36, 42-60 Journal of the American Society of Echocardiography Volmne 10 Number sional cchocardiography Three ASA m o t i o n patterns were observed: Type 1: T h e ASA projected into the right atrium during diastole, with early systolic bulging into the left atrium, followed by a rightward crossing-over m o t i o n in mid-systole and during inspiration or expiration Type 2: A sustained rightward deviation during expiration and a leftward m o t i o n occurred only during inspiration in early ventricular systole Type 3: T h e ASA remained in the right atrium, with an undulating m o t i o n during all phases o f the cardiorespiratory cycle T h a t same year H a n l e y et al studied ASA according to its m o v e m e n t by means o f t-vvo-dimensional echocardiography in 80 consecutive patients H e classified ASA as follows: Type 1A: T h e bulging in the right atrium being motionless Type 1B: T h e bulging confined to the right atrium but with rapid phasic oscillation during inspiration Type 2: T h e ASA p r o t r u d i n g maximally into the left atrium and accompanied by excursion into the right atrium Hanley's ASA types 1A and 1B were similar to those published by Longhini I n 1989 R o u d a u t et al studied 44 patients with two-dimensional echocardio g r a p h y and also identified three distinct groups o f ASA: type I, with aneurysms involving only the fossa ovalis; type II, involving the fossa ovalis and the posterior p o r t i o n o f the atrial septum (in types I and II, the ASA protrudes only to the right atrium); and type I I I , with aneurysms involving the entire atrial septum (type I I I protrudes only to the left atrium) I n 1991 Pearson et al 16 in a T E E study added a new type o f A S A - - t y p e 1C I n four patients he observed that the ASA m o v e m e n t is predominantly to the right atrium with left atrial excursion during early systole This m o v e m e n t was intensified by inspiration or the Valsalva maneuver METHODS Between lanuary 1991 and April 1994, we studied 10,803 patients who were referred for TTE Of these, 205 patients fulfilled the echocardiographic criteria for ASA Proposed New Classification We propose a modification of the existing classifications In our study of 205 consecutive patients with ASA, we analyzed all possible excursions and describe two previously Olivares-Reyes Table e t al 645 New Classification of Atrial Septal Aneurysm TYPE 1R: The ASA protrudes from the midlinc of the atrial to the right atrium throughout the cardiorespiratory cycle TYPE 2L: The ASA protrudes from the midline of the atrial septum to the left atrium throughout the cardiorespiratory cycle TYPE 3RL: The maximal excursion of the ASA is toward the right atrium with a lesser excursion toward the left atrium TYPE 4LR: The maximal excursion of the ASA is toward the left atrium with a lesser excursion toward the right atrium TYPE 5: The ASA movement is bidirectional and equidistant to the right as well as to the left atrium during the cardiorespiratory cycle unclassified types of ASA movement which have been called types "2L" and "5." Nomenclature Five possible types of ASA movements were observed in this study We have added tile letter "R" after the number if the septal bulging is toward the right atrium and the letter "L" if the bulging is toward the left atrium A second letter is added to those ASAs which have excursion into both atria In that case the first letter indicates the predominant direction of the pron'usion, and the letter in the second position indicates the lesser and opposite excursion In the case where the aneurysm bulges throughout both atria in an equal or bidirectional fashion, this type is not followed by any letter and the number is used alone (type 5) (Table and Figure 1) Echocardiographic Examination The echocardiographic studies were performed with three commercially available ultrasound systems (Acuson 128, Acuson 128 XP/10c, and Hewlett-Packard sonos 500) with 2.5 to M H z phased-array imaging transducers All systems were capable of both Doppler color and spectral flow All patients underwent standard TTE views including parasternal long-axis, short-axis, and apical five-, four-, three-, and two-chamber views, as well as subcostal fourchamber and short-axis views The studies were performed with the patient in supine and left lateral decubitus positions during quiet respiration Particular attention was given to subcostal views with appropriate transducer angulation to visualize the heart completely in four-chamber view and the interatrial septum with its foramen ovale segment in particular The atria, including the atrioventricular valves, was magnified to ease the visualization of movement and measurement of the ASA Patients were placed in the supine position with legs and knees flexed They were in quiet respiration and sustained inspiration TEE was performed in 25 patients who underwent prior TTE studies and who had a diagnosis or suspicion of ASA 646 Journalof the AmericanSocietyof Echocardiography July-August 1997 Olivares-Reyes et al N E W C L A S S I F I C A T I O N OF ATRIAL SEPTAL A N E U R Y S M Type 3Rk Type 4LR Type Figure Echocardiographic four-chamber view, as well as the different bulgings of the atrial septum with aneurysm, showing the new classification of atrial septal aneurysm and how normally the atrial septum is seen in a two-dimensional depiction All of them had additional indications such as rule-out source of embolism, masses or thrombus, intracavitary shunts, and vegetation TEE was performed after administration oforopharyngeal anesthesia with lidocaine (10%) or aerosolized benzocaine (14%) and occasionally diazepam for sedation The studies were performed with an Acuson 128 and Acuson 128 XP/10c ultrasound system, with to MHz single or biplane TEE probes Standard TEE views were obtained aneurysm was observed in subcostal, apical four-chamber, and parasternal short-axis views at the level of the great vessels Sometimes the bulging was also seen in apical twoand three-chamber views The classification of ASA was made according to its different movements, as in previous classifications and regardless of its possibly different etiology Contrast Study Mitral valve prolapse (MVP) and tricuspid valve prolapse (TVP) were diagnosed in the parasternal long-axis view, M-mode, and apical two- and four-chamber view using as diagnostic criteria any leaflets prolapsed behind the plane of the valve anulus in at least two different views and the presence of any degree of valvular regurgitation Contrast studies were performed during the TEE in patients in whom intracavitary shunt was suspected Ten milliliters of vigorously agitated saline solution was injected in an antecubital vein during normal respiration and during a series of coughs or Valsalva maneuver Diagnosis of PFO was made if microbubbles were observed in the left atrium during the first three or four heart beats of opacification of the right atrium ASD was diagnosed if a "clean area" (negative effect) was produced near the interatrial septum when the right atrium was opacificated by the microbubbles Criteria for ASA The diagnostic criteria for ASA was made if a sacculation or deformity in the intcratrial septum or the foramen ovale region was seen An excursion of-> 10 mm into the right or left atrium or if the sum of bilateral excursions of > 10 mm was required The minimal aneurysmal base amplitude (width) accepted in this study was 15 mm in diameter The Mitral and Tricuspid Valve Prolapse Valvular Regurgitation Valvular regurgitation was grade as + (tracc), + (mild), + (moderate), and + (severe) Left Ventricular Hypertrophy Left ventricular hypertrophy (LVH) was defined as left ventricular mass index61 (LV mass/body surface area [m 2] ) ->120 g m / m Left ventricular mass was calculated with the formula: LV mass (gm) = 1.05 ([LV internal diameter + LV septal thiclmess + posterior wall thickness] a - [LV internal diameter]) a All measurements done in this study were made according to the recommendations of the American Society of Echocardiography 62 Journal of the American Society of Echocardiography Volume 10 Number Table Olivares-Reyes et al 647 Atrial septal aneurysm in 205 patients clinical variables Patient Gender F: 135 (66%) M: 70 (34%) Age (yr) HTN CAD DM CVE SVTA 63 (25-97) 132 (64%) 65 (32%) 37 (18%) 40 (20%) 33 (16%) Echocardiographic variables PHT MR AI TR VP EF LVE LAE RYE RAE DCM LVH PFO ASD MAS ChN 58 93 51 94 20-89 42 17 19 78 19/6 7 (Th 5, Tu 2) (28%) (45%) (25%) (46%) 31 (MV 22, TV 7, MT 2) (15%) (62%) (4%) (20%) (8%) (9%) (3%) (38%) (32%) (3%) (3%) (4%) AI, Aortic insutiqciency;ASD, atrial septal defect; CAD, coronary artery disease; CVE, cerebrovascular events; C/aN, Chiari's network; DCM, dilated cardiomyopathy; DM, diabetes mellitus; EF~ejection fraction; HTN, systemic hypertension; LAE, left atrial enlargement; LVE, left ventricular enlargement; MAS, mass; MR, min'al regurgitation; M-T, mitral-tricuspid; MI/P, mitral valve prolapse; PFO,patent foramcn ovale; PHT;, pulmonary hypertension; RAE, right atrial enlargement; RVE~ right ventricular cnlargement; SVTA, supra-vcntricular tachyarrhythmias; Th, thrombus; TR~ tricuspid regurgitation; Tu, tumor; TVP, tricuspid valve prolapse; VP, valvular prolapse All the studies were taped, and hard copies were taken for further analysis and measurements All cases were reviewed by three different obsmwers ASA limited to the fossa ovalis and 28 (14%) had ASA involving the entire septum CVA a n d TIA Statistical Analysis The data were analyzed with Student's ttest and chi-square test and are given as mean -+ standard deviation A p value i mm of excursion are *References 6, 7, 9, 12, 16, 21, 42-60 associated with a higher risk of stroke They also concluded that ASA and PFO are significantly associated with stroke if considered individually and that the simultaneous presence of both had a strong synergistic effect In the same way Siostronek et al 14 reported 20% versus 0% (p = 0.0006) in the association of PFO and ASA in 99 patients with suspected cardiac source of embolism Interatrial communication (ASD and PFO) and ASA showed a high association (up to 90%) of cases with stroke 8,9,21 Arrhythmias Atrial arrhythmias have been associated with ASA2 It has been speculated that ASA movements initiate the arrhythmia In Longhini's study1° 57% of patients had associated SVA Hanley et al.8 found SVTA in 25% of their patients; of these, 20% had no other potential cause ofarrhythmias other than ASA Sixty-five percent of all patients with SVTA had the mobile ASA (types 1B and 2) Mfigge et al?s reported SVTA in 24% Schneider et al.6s reported SVTA in 52% of 50 patients with ASA, using Holtcr monitor in all of them In this study, we found a total of 37 instances of SVTA (18%) in 33 patients, which represents 16% of all patients Sixty-seven percent of these had atrial fibrillation, 27% had atrial flutter, 9% had paroxysmal SVTAs, and one patient (3%) had frequent premature atrial contractions and a short episode of ventricular tachycardia Eleven of these patients (33%) had ASA as the only possible cause of arrhythmia All had hypertension, 42% had left atrial enlargement, 36% had systolic dysfunction, 31% had right atrial enlargement, 24% had coronary artery disease, and 9% had valvular prolapse In the analysis of these variables by type, SVTA was more frequent in ASA type L R (23%); 75% of patients with SVTA related topredominantly left bulging ASA Finally, no differences were found among these patients regarding mobile versus fixed ASA The lower incidence of atrial arrhythmia in this study may be due to the lower number of patients who had 24-hour ambulatory monitoring Although association with cardiac abnormalities can be arrhythmogenic, such as hypertension, atrial enlargements, systolic dysfunction, coronary artery disease, or valvular prolapse, a third of these patients had ASA as the only possible cause of SVTA Valvular Prolapse MVP is one of the more frequent abnormalities seen w i t h ASA 2,8,1°,23,26-35 Some authors hypothesize that tReferences 8, 10, 26, 35, 41, 42, 63-68 Journal of the American Society of Echocardiography Volume 10 Number Olivares-Reyes et 653 Table Comparisonof predominantly left-bulging ASA types (2L + 4LR) versus predominantly right-bulging ASA types (1R + 3RL)* Left-bulging (134 patients) versus fight-bulging (57 patients) ASA Values Age (yr) Gender (men) Systemic hypertension Diabetes mellitus Cerebrovascular events Pulmonary hypertension Right ventricular enlargement Right atrial enlargement Left ventricular hypertrophy Patent foramen ovale 65 ± 17 50(37) 92(69) 29(22) 29(22) 42(31) 14(10) 15(11) 59(44) 5(4) vs 58 - 18 vs 14(25) vs 32(56) vs 6(11) vs 9(16) vs 12(21) vs 2(3) vs 3(5) vs 13(23) vs 0(0) p Value 0.0001 NS NS NS NS NS NS