Table 2.

List of included studies and PFO prevalence by diagnostic modality in the young.

Studies—young	Healthy/control population	Cryptogenic events	Non-cryptogenic events	Age (years)
	PFO(+)/Total Prevalence (%)	PFO(+)/Total Prevalence (%)	PFO(+)/Total Prevalence (%)
Transesophageal Echocardiography
Cabanes et al. (26)	9/50	36/64	7/36	<55
	18	56.3	19.5
Jones et al. (27)	2/19	4/14	3/12	<50
	11	28.6	25
Job et al. (28)	27/63	27/41	11/33	<55
	43	65.8	33.3
Mesa et al. (30)	7/35	23/55		<50
	20	42
Cerrato et al. (31)	6/27	27/53		<50
	22.2	51
Hausmann et al. (32)	2/18	9/18	0/1	<40
	11.1	50	0
Schuchlenz et al. (34)	38/123	54/66		<60
	30.9	81.8
Schwerzmann et al. (35)	16/93			Young
	17.2
Ranoux et al. (36)		31/54	1/14	<55
		57.4	7.1
Mas et al. (39)		267/581		<55
		46
Handke et al. (42)		36/82	7/49	<55
		43.9	14.3
Komar et al. (46)		69/88		<55
		78.4
Nighoghossian et al. (49)		27/79		<60
		34
Mesa et al. (51)		70/194		<55
		36
Total	107/428	680/1,389	29/145
	25	48.9	20
Transthoracic Echocardiography
Lechat et al. (52)	10/100	20/41	4/19	<55
	10	48.8	21
Webster et al. (55)	6/40	19/34		<40
	15	55.9
Di Tullio et al. (56)		10/21	1/24	<55
		47.6	4.2
Jeanrenaud et al. (57)		8/11	0/5	<50
		72.7	0
Total	29/140	57/107	5/48
	11.4	53.3	10.4
Transcranial Doppler
Del Sette et al. (59)	8/50			<50
	16
Anzola et al. (60)	5/25			<55
	20
Domitrz et al. (61)	16/65			<55
	24.6
Koutroulou et al. (62)	50/115	42/84		<55
	43.5	50
Serena et al. (63)		162/229		<55
		70.7
Mazzuco et al. (64)		29/74	16/52	<60
		39.2	30.8
Palazzo et al. (65)		34/47		<55
		72.3
Yeung et al. (66)		16/27		<50
		59.3
Carod-Artal et al. (69)		37/90	5/40	<45
		41.1	11.1
Total	79/255	320/551	21/92
	31	58.1	22.8