Technetium-99m-labeled macroaggregated albumin lung perfusion scan for diagnosis of hepatopulmonary syndrome: A prospective study comparing brain uptake and whole-body uptake

Table 1 Demographics and clinical characteristics of patients with and those without intrapulmonary vascular dilatations

	All patients, n = 69	IPVD, n = 32	Non-IPVD, n = 37	P value
Age in yr	53.6 ± 12.2	54.1 ± 11.6	53.1 ± 12.8	0.739
Sex, male/female	46/23 (67/33)	21/11 (66/34)	25/12 (68/32)	0.864
Etiology				0.460
Hepatitis B virus infection	16 (23)	7 (22)	9 (24)
Budd-Chiari syndrome	15 (22)	6 (19)	9 (24)
Hepatocellular carcinoma	15 (22)	9 (28)	6 (16)
Alcoholic liver disease	10 (14)	5 (16)	5 (14)
Cryptogenic	4 (6)	3 (9)	1 (3)
Others	9 (13)	2 (6)	7 (19)
Child-Pugh class, A/B/C	31/32/6 (45/46/9)	11/18/3 (34/56/10)	20/14/3 (54/38/8)	0.262
Child-Pugh score	7.0 ± 1.6	7.2 ± 1.6	6.9 ± 1.6	0.457
MELD score	9.8 ± 2.9	9.8 ± 2.5	9.7 ± 3.2	0.913
Bilirubin in mg/dL	1.5 ± 0.8	1.7 ± 1.0	1.3 ± 0.5	0.198
Albumin in g/L	35.4 ± 5.2	35.2 ± 5.5	35.6 ± 5.1	0.720
Creatinine in mg/dL	0.77 ± 0.22	0.71 ± 0.18	0.83 ± 0.23	0.041
International normalized ratio	1.26 ± 0.18	1.26 ± 0.15	1.26 ± 0.20	0.963
Variceal bleeding	38 (55)	17 (45)	21 (55)	0.762
Ascites	37 (54)	19 (51)	18 (49)	0.373
FEV1/FVC, % predicted	85.3 ± 6.8	84.4 ± 6.2	86.2 ± 7.5	0.553
Arterial blood gas
PaO2 in mmHg	85.8 ± 13.2	81.0 ± 12.1	90.1 ± 12.8	0.004
PaCO2 in mmHg	35.7 ± 5.1	36.5 ± 4.5	35.1 ± 5.6	0.255
AaO2 in mmHg	19.6 ± 14.0	23.2 ± 13.3	16.4 ± 14.1	0.043
MAA shunt fractions derived from different formulas
Brain-lung uptake	4.4 ± 4.3	5.3 ± 6.0	3.6 ± 1.8	0.245
Whole-body uptake	43.8 ± 8.2	48.0 ± 6.1	40.1 ± 8.1	0.001

Data are presented as means ± SD or as numbers of patients (percentiles). IPVD: Intrapulmonary vascular dilatations; MELD: Model for end-stage liver disease; FEV₁: Forced expiratory volume in 1 second; FVC: Forced vital capacity; PaO₂: Partial arterial pressure of oxygen; PaCO₂: Partial arterial pressure of carbon dioxide; AaO₂: Alveolar-arterial oxygen gradient.

Table 2 Demographics and clinical characteristics of patients who underwent acquisition of local images followed by whole-body images and vice versa

	Local images followed by whole-body images, n = 33	Whole-body images followed by local images, n = 36	P value
Age in yr	52.8 ± 12.0	54.4 ± 12.5	0.588
Sex, male/female	20/13 (61/39)	26/10 (72/28)	0.307
Etiology			0.161
Hepatitis B virus infection	12 (36)	4 (11)
Budd-Chiari syndrome	7 (21)	8 (22)
Hepatocellular carcinoma	4 (12)	11 (31)
Alcoholic liver disease	4 (12)	6 (17)
Cryptogenic	2 (6)	2 (6)
Others	4 (12)	5 (14)
Child-Pugh class, A/B/C	16/16/1 (48/48/3)	15/16/5 (42/44/14)	0.344
Child-Pugh score	6.9 ± 1.5	7.1 ± 1.7	0.458
MELD score	9.4 ± 2.4	10.0 ± 3.2	0.436
Bilirubin in mg/dL	1.5 ± 0.9	1.5 ± 0.7	0.958
Albumin in g/L	35.0 ± 5.0	35.8 ± 5.5	0.510
Creatinine in mg/dL	0.76 ± 0.21	0.78 ± 0.23	0.757
International normalized ratio	1.24 ± 0.14	1.28 ± 0.20	0.298
Variceal bleeding	22 (58)	16 (42)	0.064
Ascites	16 (43)	21 (57)	0.413
FEV1/FVC, % predicted	86.3 ± 7.5	84.3 ± 6.2	0.524
Arterial blood gas
PaO2 in mmHg)	87.6 ± 10.0	84.2 ± 15.6	0.283
PaCO2 in mmHg	35.9 ± 5.1	35.6 ± 5.2	0.785
AaO2 in mmHg	17.5 ± 11.4	21.6 ± 16.0	0.225
IPVD	13 (41)	19 (59)	0.265
HPS	12 (46)	14 (54)	0.829
Brain-lung uptake	3.5 ± 1.7	5.3 ± 5.6	0.158
Whole-body uptake	42.7 ± 10.0	44.7 ± 6.5	0.393

Data are presented as means ± SD or as numbers of patients (percentiles). MAA: Technetium-99m-labeled macroaggregated albumin; MELD: Model for end-stage liver disease; FEV₁: Forced expiratory volume in 1 second; FVC: Forced vital capacity; PaO₂: Partial arterial pressure of oxygen; PaCO₂: Partial arterial pressure of carbon dioxide; AaO₂: Alveolar-arterial oxygen gradient; IPVD: Intrapulmonary vascular dilatations; HPS: Hepatopulmonary syndrome.

Table 3 Multivariable logistic regression analysis of intrapulmonary vascular dilatations

Variable	β coefficients	SE	P value	OR	95%CI
Age	0.008	0.028	0.768	1.008	0.954–1.066
Sex	0.372	0.938	0.692	1.450	0.230–9.122
Creatinine	-2.350	2.257	0.298	0.095	0.001–7.949
Whole-body uptake	0.254	0.095	0.008	1.289	1.069–1.554

IPVD: Intrapulmonary vascular dilatations; SE: Standard error; OR: Odds ratio; CI: Confidence interval.

Table 4 Utility of macroaggregated albumin lung perfusion scan for detecting intrapulmonary vascular dilatations

	Sensitivity, %	Specificity, %	PPV, %	NPV, %	Accuracy, %
CEE	100	86	81	100	91
Brain-lung uptake > 6%	19	92	67	58	59
Brain-lung uptake > 5.7%	23	89	64	58	59
Whole-body uptake > 42.5%	100	52	65	100	74

MAA: Technetium-99m-labeled macroaggregated albumin; IPVD: Intrapulmonary vascular dilatations; CEE: Contrast-enhanced echocardiography; PPV: Positive predictive value; NPV: Negative predictive value.