Bayés syndrome and acute cardioembolic ischemic stroke

Table 1 Demographic, cerebrovascular risk factors, neuroimaging and outcome in the first-ever cardioembolic stroke vs first-ever non-cardioembolic cerebral infarct population

Variable	Cardioembolic stroke n = 575	Non-cardioembolic cerebral infarct1 n = 1507	P value
Age, yr, mean (SD)	78.96 (9.39)	73.45 (12.8)	0.0001
Age strata, yr			0.0001
< 65	44 (7.6)	285 (18.9)
65-74	116 (20.2)	405 (26.9)
75-84	251 (43.7)	557 (37.0)
≥ 85	164 (28.5)	260 (17.3)
Sex			0.0001
Males	199 (34.6)	788 (52.3)
Females	373 (65.4)	719 (47.7)
Hypertension	291 (50.6)	835 (55.4)	0.049
Diabetes	103 (17.9)	368 (24.4)	0.002
Atrial fibrillation	433 (75.3)	176 (11.7)	0.0001
Heavy smoking (> 20 cigarettes/d)	23 (4.0)	184 (12.2)	0.0001
ACM vascular topography	391 (68.0)	703 (46.6)	0.0001
Echocardiography	363 (63.1)	598 (39.7)	0.0001
Symptom-free at discharge	82 (14.3)	300 (19.9)	0.003
In-hospital death	126 (21.9)	123 (8.2)	0.0001
Transfer to convalescent/rehabilitation units	89 (15.5)	154 (10.2)	0.001
Length of stay, days, median (interquartile range)	15 (10-24)	11 (8-19)	0.0001
Prolonged hospital stay > 12 d	330 (57.4)	650 (43.1)	0.0001

Data expressed as numbers and percentages in parenthesis.

¹Atherothrombotic, n = 565; lacunar, n = 566; essential, n = 280; unusual, n = 96.

Table 2 Main studies of interatrial block as a cerebrovascular risk factor or as a predictor for acute ischemic stroke (period 1979-2016)

Ref.	Study type	n	Age (yr)	Gender	Inclusion criteria	Exclusion criteria	Confounding factors	Parameters evaluated	Results
Wu et al[32]	Retrospective cohort	1046	63 ± 10	612 males 434 females	Patients hospitalized in Zhengzhou University People's Hospital for diagnosis and treatment between March 1 and March 31 of 2010 ECG Presence of IAB	History of AF Patients under anticoagulant treatment Missing data for calculation of CHADS2 and CHA2DS2-VASc scores Lost to follow-up	Congestive Heart Failure Hypertension Diabetes Mellitus Previous strokes/TIA Coronary Artery Disease PCI during index admission CABG during index admission Tobacco consumption LVEF LA diameter Medication Use	Conduction lengths CHADS2 and CHA2DS2-VASc scores Apparition of Stroke (Hemorrhagic or Ischemic)	Mean follow-up of 4.9 ± 0.7 yr 0.8% hemorrhagic stroke 5.3% presented ischemic stroke or TIA Ischemic stroke or TIA increased with CHADS2 score: 0.37, 0.85, 0.96 and 1.92 per 100-person years for scores of 0, 1, 2, and > 3 respectively CHA2DS2-VASc scores correlated with Ischemic stroke or TIA (0.19, 0.59, 0.76, 0.88, and 2.0 for scores of 0, 1, 2, 3, and > 4 respectively) Cut-off points: > 3 for CHADS2, > 4 for CHA2DS2-VASc Conclusion: CHADS2 and CHA2DS2-VASc scores may be predictors of risk of ischemic stroke or TIA in patients with IAB without atrial fibrillation
Martinez-Selles et al[40]	Case-control	80	101.4 ± 1.5	21 males 59 females	Patients from the Cardiac and Clinical Characterization of Centenarians (4C) Registry	Hospitalized patients	Dementia Perceived health status score Previous stroke Mitral regurgitation Systolic dysfunction Left atrial diameter > 40 mm	Conduction lengths ECG measurements Short Portable Mental Status Questionnaire Premature atrial beats	IAB group showed higher rate of previous stroke than normal P wave and AF groups Premature atrial beats were more frequent in advanced IAB than normal P-wave Mitral regurgitation could play an important role in IAB Conclusion: Advanced IAB is a pre-atrial fibrillation condition associated with premature atrial beats. Atrial arrhythmias and IAB occurred more frequently in centenarians than in septuagenarians.
O'Neal et al[24]	Retrospective cohort	14716	54 ± 5.8	6622 males 8094 females	Patients enrolled in the ARIC Study Recruited between 1987 and 1989	Patients with prevalent stroke or AF at baseline Race other than black or white Black participants from Washington County and Minneapolis	Black Tobacco use Diabetes LDL cholesterol level BMI Hypertension Antihypertensive medication Coronary heart disease Heart failure	Conduction lengths Presence of stroke Stroke type	Incidence rate of ischemic stroke was higher in aIAB (8.05/1000 person-years vs 3.14; P < 0.0001) Conclusion: aIAB was associated with incident ischemic stroke
O'Neal et al[29]	Retrospective cohort	14625	54 ± 5.8	6581 males 8044 females	Patients enrolled in the ARIC Study Recruited between 1987 and 1989	Participants with AF at baseline Missing baseline covariates Missing follow-up data Race other than black or white Black participants from Washington County and Minneapolis	Black Tobacco consumption Diabetes LDL cholesterol level BMI Hypertension Antihypertensive medication	Conduction lengths	Total of 262 aIAB (69 baseline, 193 new) 1929 AF cases were identified aIAB patients presented an AF incidence of 29.8/1000 vs 6.8/1000 of non-aIAB; HR = 3.09 (P < 0.0001) Conclusion: aIAB is a useful marker to identify high risk subjects for developing atrial fibrillation
Pirinen et al[41]	Case-control	690	15-49	438 males 252 females	Correct diagnosis of IS Part of the Helsinki Young Stroke Study	Unknown stroke date Outpatient treatment only No ECG OR only take on the day of stroke in ER OR no ECG between day of stroke and 14 d after	Coronary heart disease Heart failure Obesity Hypertension Tobacco use Dyslipidemia CHF Preexisting AF #VALUE	Arrhythmia types Conduction lengths Stroke etiology	Most Common ECG abnormalities: T-wave inversion (LVH (14%), prolonged P-wave (13%), prolonged QTc (12%). Most ECG abnormalities in the Stroke Etiology Subgroups: HRCE, LAA and SVD Conclusion: Routine ECG provides useful information for directing the work-up of a young IS patient. In addition to AF, P-terminal force in particular showed a strong association with etiology of high-risk source of cardioembolism
Enriquez et al[42]	Prospective cohort	187	67 ± 10.7	Not reported	Patients with typical atrial flutter (AFI) with no prior history of AF referred for CTI ablation	Patients that had received repeat ablations or did not demonstrate a bidirectional block	Composite of Cardiovascular Disease not reported	Conduction lengths Ejection fraction Holter monitoring	Advanced IAB was detected in 18.2% of patients Left atrium was larger in aIAB (46.2 ± 5.9 mm vs 43.1 ± 6.0 mm; P = 0.01) 35.8% of patients developed new-onset AF
Cotter et al[31]	Retrospective cohort	51	17-73	28 males 23 females	ILR implanted after unexplained ischemic stroke Brain imaging consistent with embolism Arterial imaging Structural cardiac imaging and rhythm monitoring 50 d of continuous monitoring	TIA Documented cause of stroke before ILR implantation Intrinsic small-vessel disease cause Atheromatosis stenosis > 50% or dissection High-risk cardiac embolic source No AF detected in 24 h - Holter	Not reported	Rhythm monitoring ECG Conduction lengths CHADS2 and CHA2DS2-VASc scores	25.5% of cases had AF IAB more prevalent in patients with AF (P = 0.02) AF patients larger LA volumes (P = 0.025) Mean AF duration was 6 min Conclusion: In patients with unexplained stroke atrial fibrillation was detected by implantable loop recorders in 25.5%. IAB was an independent predictor of AF
Cotter et al[30]	Case-control	78	24-55	49 males 29 females	≤ 55 yr at time of stroke Index cerebral infarct with no cause found CT or MRI imaging, cervical vascular imaging, ECG and rhythm monitoring	Poor quality data	Not reported	Conduction lengths PFO status A-S-C-O Classification	IAB more frequent in cases than controls (40% vs 13%) (P < 0.05) 74.6% of stroke showed PFO (70.3% large) No statistical difference of P-wave length (with vs without PFO) Conclusion: In young patients with unexplained stroke, particularly those with patent foramen ovale atria l dysfunction is a possible mechanism of stroke
Ariyarajah et al[43]	Case-control	66	60-87	39 males 27 females	Definitive acute or subacute cerebral infarct Probable embolic origin	No 12-lead ECG during 14 d post infarct Non-sinusal rhythm detected in ECG	Hypertension Valvulopathies Cardiomyopathies Tobacco Use Dyslipidemia Diabetes Mellitus Hyper/Hypothyroidism COPD Florid Heart Failure Cardiac Catheterization Myocardial Infection Valvuloplasty Previous strokes/ TIA History of AF/Flutter CAD	Echocardiogram Conduction lengths	61% IAB prevalence CAD paroxistically more present in control, perhaps due to atherosclerotic origin LA more prevalent in IAB group, with greater LA thrombi (83% vs 0%) Conclusion: IAB could be a risk factor for embolic stroke due to its known sequelae of left atrial dilation and electromechanical dysfunction that predispose to thrombosis
Ariyarajah et al[2]	Case-control	228	30-102	118 males 110 females	Studied for suspicion of stroke with CT Scan and MRI	No 12-lead ECG during 14 d post infarct	Hypertension Valvulopathies Cardiomyopathies Tobacco Use Dyslipidemia Diabetes Mellitus Hyper/Hypothyroidism COPD Florid Heart Failure Cardiac Catheterization Myocardial Infection Valvuloplasty Previous strokes/ TIA History of AF/Flutter CAD	Conduction lengths Stroke etiology	61% IAB embolic vs 40% non-embolic (P = 0.006) Hypertension for embolic stroke (P < 0.0001) Conclusion: IAB could be a novel risk for embolic stroke
Ariyarajah et al[12]	Prospective cohort	32	66-94	15 males 17 females	Saint Vincent Hospital general patients (December 15, 2004 to January 14, 2005) Resting ECG obtained on admission Existing 2-dimensional transthoracic echocardiograms Sinus rhythm	Not reported	Mitral or tricuspid valvular disease Hypertension Coronary artery disease Hyperlipidemia Diabetes mellitus History of AF/Flutter ACEI use Beta-blocker use Statins use	Conduction lengths LA dimension LVEF Cardiovascular events (heart failure, peripheral embolism, transient ischemic attack, stroke, atrial tachyarrhythmias)	Coronary disease was more prevalent in the IAB group Cardiovascular events were overall most significant in IAB, except for stroke, TIA, peripheral arterial embolism and atrial flutter Conclusion: In patients with comparable echocardiographic parameters, IAB remained associated with atrial fibrillation after 15-mo follow-up
Lorbar et al[33]	Retrospective cohort	104	22-101	58 males 46 females	St Vincent Hospital (January 2000 to December 2001) patients with ICD codes for embolic stroke Diagnosis of embolic ischemic stroke or TIA by a neurologist with or without imaging techniques	Cerebrovascular events non ICD codes Dementia, seizure, hypertensive encephalopathy, subdural hematoma, dizziness, vertigo, psychosis, and headache	Not reported	Conduction lengths ECG patterns	41% history of AF, or newly diagnosed AF 80% normal sinus rhythm patients showed IAB on concurrent ECG Conclusion: IAB may represent a new factor for stroke
Jairat et al[23]	Prospective cohort	1000	24-94	585 males 415 females	Saint Vincent Hospital general patients	Not reported	Not reported	Conduction lengths ECG patterns	32.8% of all patients showed IAB 41.1% of sinus rhythm patients showed IAB Conclusion: Patients with IAB must be followed for atrial enlargement, potential thrombosis, and the onset of atrial fibrillation

ACEI: Angiotensin converting enzyme inhibitor; AF: Atrial fibrillation; aIAB: Advanced intraatrial block; BMI: Body mass index; CABG: Coronary artery bypass grafting; CAD: Coronary artery disease; COPD: Chronic obstructive pulmonary disease; CHF: Chronic heart failure; CT: Computed tomography; CTI: Cavotricuspid isthmus; DM1: Diabetes mellitus 1; DM2: Diabetes mellitus 2; ECG: Electrocardiogram; ER: Emergency room; HR: Hazard ratio; HRCE: High-risk source of cardioembolism; IAB: Intraatrial block; ILR: Implantable loop recorder; IS: Ischemic stroke; LA: Left atrium; LAA: Large artery atherosclerosis; LDL: Low density lipoprotein; LVEF: Left ventricular ejection fraction; LVH: Left ventricle hypertrophy; MRI: Magnetic resonance imaging; PCI: Percutaneous coronary intervention; PFO: Permeable foramen ovale; SVD: Small-vessel disease; TIA: Transient ischemic attack; ARIC: Atherosclerosis Risk in Communities.