Table 3

Comparison of findings from different methods used to detect PAVMs

		Patient population		Sensitivity		Specificity		No. of PAVMs missed compared with angiography		No. where PAVMs not detected at angiography	Reference
		Total	PAVM present	Sensitivity		Specificity		No. of PAVMs missed compared with angiography		No. where PAVMs not detected at angiography	Reference	No PAVM	Unknown
Radiology
Chest radiography	98	12	84	2	83% (52–98)	92% (84–97)	2 (2% of pts)	7 (7% of pts)^3-151	42
CT scans	40™	40	0	0			2/109 PAVMs (2%)	42/109 PAVMs (39%)	88
Hypoxaemia
Pao ₂	98	12	84	2	67% (35–90)	61% (50–71)	4 (4% of pts)	33 (34% of pts)^3-151	42
Sao ₂ erect ⩽96%	66	66	0	0	73%	35%		0^3-150	89
R-L shunts
100% oxygen
shunt >5%	37	8	28	1	88% (47–100)	72% (51–87)	1 (2.7% of pts)	8/15 (53% of pts)^3-151	42
Contrast echocardiography	21	15	6	0				6 (28% of pts)	90
^99mTc scan
shunt >5%	66	66	0	0	68%	72%		0^3-150	89
shunt >3.5%	66	66	0	0	87%	61%		0^3-150	89

Pao ₂ = arterial oxygen tension; Sao ₂ = arterial oxygen saturation.
↵3-150 Method of patient ascertainment in reference 89.
↵3-151 The angiographic data were obtained by intravenous rather than pulmonary artery catheter DSA: the number of “overdiagnosed” PAVMs may therefore include some PAVMs missed by this less sensitive angiographic method. Data obtained from HHT family screening programmes^{42 90} or known PAVM patients.88 ,89