1. ALL’ IPERTENSIONE POLMONARE
CORSO DI CLINICAL COMPETENCE SULLA
MALATTIA TOMBROEMBOLICA VENOSA
Firenze 4-5 Novembre 2010
DALLA TROMBOSI VENOSA
ALL’ EMBOLIA
ALL’ IPERTENSIONE POLMONARE
“Scintigrafia polmonare”
C. Marini, Dipartimento Cardio-Toracico e Vascolare
Università di Pisa, e Fondazione CNR/Regione Toscana
“Gabriele Monasterio”, Pisa.

2. Background. 1
“Prior to 1960, physician diagnosed pulmonary embolism (PE) by the identification of a suspicious combination of symptoms, signs, and non-specific laboratory tests.
After 1960, the diagnostic capabilities were enriched by the development of angiographic and radionuclide pulmonary imaging techniques1,2.”
Williams JR, et al. JAMA 1963;184:
Wagner HN Jr, et al. N Engl J Med 1964;271:

3. Background. 2
“Although invasive, angiography became a “gold standard” for a validation of any other technique in the diagnosis of PE, even though it was reported that a normal perfusion lung scan essentially excludes the presence of PE1.
In the mid ‘70s, due to some limitations of pulmonary angiography, ventilation scan (V) was added to perfusion lung scan (Q) to increase diagnostic capability for PE by non-invasive techniques2.”
1. Dalen JE, et al. Am Heart J 1971;81:
2. McNeal BJ, et al. JAMA 1974;227:

4. Rapporto ventilazione/perfusione nella embolia polmonare acuta (EPA)
La strategia diagnostica era basata sulla aspettativa (teorica) dei rapporti ventilazione/perfusione (V/Q) :
Ventilazione normale nelle zone con alterata perfusione (V/Q mismatch) 1,2 : EPA;
Ventilazione alterata nelle zone con alterata perfusione (V/Q match) 3: no EPA .
De Nardo GL, Goodwin DA, Ravasini R, Dietrich PA. The ventilatory lung scan in the diagnosis of pulmonary embolism. N Engl J Med 1970; 282:
2. McNeil BJ, Holman BL, Adelstein SJ. The scintigraphic definition of pulmonary embolism. JAMA 1974; 227:
3. Miller RF, O’Doherty MJ. Pulmonary nuclear medicine. Eur J Nucl Med 1992;19:

5. Background. 3
“Despite the availability of this new diagnostic tool (V/Q lung scan), a retrospective clinical pathologic correlative study published in the early ‘80s indicated a frequency of only 10% of in vita successful PE diagnosis1.
In other words, the PE diagnosis was still a problem, and the use of V/Q lung scan did not increase the diagnostic capability2.”
Goldhaber SZ, et al. Am J Med 1982;73:
Hull RD, et al. Chest 1985;88:

6. The PIOPED  study
Prospective Investigation of Pulmonary Embolism Diagnosis
( JAMA 1990;263: )
Aim. To determine the sensitivity and specificity of ventilation-perfusion (V/Q) lung scan for acute pulmonary embolism (PE).
Methods. To evaluate, in patients with established angiographic diagnosis, the presence and % dimention of at least two or more perfusion defects with or without matching ventilation or chest radiographic abnormalities.
Results. V/Q lung scan: sensitivity 41%, specificity 97%.
Conclusion. V/Q lung scan established the diagnosis or exclusion of PE only for a minority of patients.

7. The PISAPED study
Prospective Investigation Study of Acute Pulmonary Embolism Diagnosis.
(Miniati M, Pistolesi M, Marini C, et al. Am J Respir Crit Care Med1996;154: )
Aim. To assess the value of perfusion lung scan (PLS) alone in the diagnosis of acute pulmonary embolism.
Methods. To detect on PLS the presence (PE+) or the absence (PE-) of at least one of wedge-shaped perfusion defect with or without matching roentgenographic lung parenchimal abnormalities in patients with established angiographic diagnosis.
Results. PLS alone: sensitivity 86%, specificity 93%.
Conclusion. Accurate diagnosis of PE is possible by PLS alone.

8. Normal pulmonary angiography
Normal lung scan
Normal pulmonary angiography
Right lung
apex
apex
Anterior
Anterior 1 2 3
Right artery
lateral view 4 6 5 7 9 8
base
base
Left oblique posterior view
Left lung
apex
apex
Anterior
Anterior 1 2 3
Left artery
lateral view 4 6 5 7 8 9
base
base
Left oblique posterior view

9. (anterior-posterior view)
Acute pulmonary embolism
Left pulmonary artery angiogram
(anterior-posterior view)
Left lung perfusion scan
(left lateral view)
Apex
Anterior 1 2 3 4 6 5 7 9 8
Base

10. Lung scan with Lung scan without Normal lung scan wedge-shaped defects
Right lung
apex
Anterior
apex
apex 1 2
Anterior
Anterior 1 3 2 4 3 6 4 5 7 6 9 5 8 7 9 8
base
base
base
Right oblique posterior
Left lung
apex
apex
apex
Anterior
Anterior 1
Anterior 2 1 3 2 3 4 6 4 6 5 7 5 8 7 8 9
base
base
base
Left oblique posterior

11. PIOPED versus PISA-PED
V/Q scan
High probability
(PIOPED)
Q scan
suggestive of PE
(PISA-PED)
Sensitivity (%) 41 86
Specificity (%) 97 93

12. Alterazioni radiografiche in PIOPED e PISAPED
PIOPED: JAMA 1990;263:2753
1063 pazienti; 88% con alterazioni Rx toraciche*.
Nelle embolie, atelettasie e densità parenchimali
in 99/219 pz. (45%) a dx e 93/183 pz. (51%) a sn.
PISA-PED: Am J Respir Crit Care Med 1996;154:1387
1100 pazienti; nelle embolie, infarti in 74/440 pz.
(17%), atelettasie in 123/440 pz. (28%), elevazione
diaframma in 185/440 pz. (42%) e versamento
pleurico in 198/440 pz. (45%).
* Worsley DF, et al. Radiology 1993;189:133-6

13. The PIOPED  study sensitivity 83% 86% specificity 96% 93% PIOPED 
PISAPED
sensitivity
83%
86%
specificity
96%
93%

14. Radiation burden for commonly used imaging techniques
Dose(mSv)
Equivalent no. of chest radiographs
Ultrasonography
Chest radiography
0.02 1
Lung scintigraphy 50
Spiral CTPA 7
350

15. Costs of imaging techniques for pulmonary embolism
Cost (Euros)
Ultrasonography 72
Chest radiography 21
Lung scintigraphy (Q) 68
Lung scintigraphy (V)
198
Spiral CTPA
206

16. Follow-up scintigrafico ed emogasanalitico
in pazienti con APE
Miniati M. et al. Medicine (Baltimore) 2006;85(5):

17. Remy-Jardin M, et al. Radiology 2007;245:315-329
Management of suspected acute pulmonary embolism in the era of CTAngiography: A statement from the Fleischner Society.
Remy-Jardin M, et al. Radiology 2007;245:
“If scintigraphy is used, elimination of the ventilation scan can reduce cost and radiation. Although this is not common practice in most centers, there is evidence from two studies1,2 that ventilation scan can be eliminated without compromising diagnostic accuracy……
In addition, better sensitivity was achieved when the scans of the PIOPED I study were reread by a blinder observer using the perfusion images alone2.
Accordingly, scintigraphy can be considered as a preferred altenative chest imaging technique for patients who cannot undergo CTAngiography.”
1. Stein PD, et al. Am J Cardiol 1992;69:
2. Miniati M, et al. Am J Respir Crit Care Med 1996;154:

18. CONCLUSIONE
La scintigrafia polmonare da perfusione da sola nella diagnosi di embolia polmonare acuta:
VANTAGGI:
alta accuratezza diagnostica;
bassa esposizione radiante;
basso costo;
facile da ottenere;
facile da leggere;
innocua per il paziente;
utile per il monitoraggio del paziente .
LIMITI:
Nessuno

19. Consolidation
(infarction)
Consolidation
(no infarction)

20. Oblique posteriori destre
Scan Normale
Scan di EP
Scan di non EP
giugulo
giugulo
giugulo
base
base
base
Oblique posteriori sinistre
giugulo
giugulo
giugulo
base
base
base

21. Radiation burden for commonly used imaging techniques
Dose(mSv)
Equivalent no. of chest radiographs
Ultrasonography
Chest radiography
0.02 1
Lung scintigraphy 50
Spiral CTPA 7
350

22. Costs of imaging techniques for pulmonary embolism
Cost (Euros)
Ultrasonography 72
Chest radiography 21
Lung scintigraphy (Q) 68
Lung scintigraphy (V)
198
Spiral CTPA
206

23. Expected versus observed PE (583 patients)
Miniati et al: Am J Respir Crit Care Med 1999 1
2/187 2
PE-
Low 10
8/81 13
Intermediate 71
15/21 58
High 59
10/17
PE+ 92
59/64 93 99
212/213
(%)
PE /no. pts
Expected PE (%)
Scan
Clinical probability
119/583 = 20% need further investigation to reach diagnosis

24. Clinical probability combined with CTA results (PIOPED , 477 patients)
PE/No. of pts %
High +
22/23 96
Intermediate
93/101 92
Low
22/38 58 -
6/15 40
15/136 11
6/164 4
189/477 = 40% need further investigation to reach diagnosis

25. Miniati M, et al. Am J Respir Crit Care Med 2008;178:290-294
Pisa Model 2. AUC: 0.88
Miniati M, et al. Am J Respir Crit Care Med 2008;178:

26. Clinical models: predictors of PE
AUC: 0.78
AUC: 0.74
Wells PS, et al.
Thromb Haemost 2000;83:413
Le Gal, et al.
Ann Intern Med 2006;144:165

27. Angiografia polmonare con “Stop Flow”

28. Remy-Jardin M, et al. Radiology 2007;245:315-329
Management of suspected acute pulmonary embolism in the era of CTAngiography: A statement from the Fleischner Society.
Remy-Jardin M, et al. Radiology 2007;245:
“If scintigraphy is used, elimination of the ventilation scan can reduce cost and radiation. Although this is not common practice in most centers, there is evidence from two studies1,2 that ventilation scan can be eliminated without compromising diagnostic accuracy……
In addition, better sensitivity was achieved when the scans of the PIOPED I study were reread by a blinder observer using the perfusion images alone2.
Accordingly, scintigraphy can be considered as a preferred altenative chest imaging technique for patients who cannot undergo CTAngiography.”
1. Stein PD, et al. Am J Cardiol 1992;69:
2. Miniati M, et al. Am J Respir Crit Care Med 1996;154: