External validation of a simple non-invasive algorithm to rule out chronic thromboembolic pulmonary hypertension after acute pulmonary embolism.
OBJECTIVE
International guidelines do not provide strong recommendations on the duration and intensity of follow-up after acute pulmonary embolism (PE), nor on screening-programs for chronic thromboembolic pulmonary hypertension (CTEPH). We aimed to address this gab by performing an external validation of the easy "CTEPH rule-out-criteria" based on a normal NT-proBNP level and the absence of 3 ECG characteristics.


METHODS
134 patients underwent clinical follow-up 6months after PE. Predefined transthoracic echocardiographic (TTE) criteria were used to categorize patients as "PH unlikely" or "PH possible/likely". The latter patients underwent further (invasive) diagnostic procedures to confirm and classify the diagnosis of pulmonary hypertension. NT-proBNP and ECGs, both assessed at the day of echocardiography, were evaluated post-hoc.


RESULTS
Sixty-three patients (47%) scored none of the "CTEPH rule-out criteria" positive, of whom 61 had normal TTE (97%). Twenty-five patients (19%) were categorized by TTE as "PH possible/likely"; of those, 6 were diagnosed with CTEPH. The sensitivity of rule-out criteria for CTEPH was 100% (95%CI 56-100%; 6/6 patients identified), and for "PH possible/likely" on TTE 92% (95%CI 74-99%; 23/25 patients identified): 2 asymptomatic patients with estimated systolic pulmonary arterial pressure of 36mmHg and 38mmHg, respectively, who remained stable during further 2-year follow-up, were not identified. Inter-observer agreement for the adjudication of the ECG characteristics was excellent (kappa-statistic 0.97).


CONCLUSIONS
In this external validation cohort, we confirmed the diagnostic accuracy and reproducibility of the "CTEPH rule-out criteria". These results provide a solid ground for future outcome trials applying this algorithm.
Center for Thrombosis and Hemostasis (CTH), University Medical Center Mainz, Germany.
F A
FA
Klok
Department of Cardiology and Pulmonology, Heart Center, University of Göttingen, Germany.
C
C
Tesche
Department of Cardiology and Pulmonology, Heart Center, University of Göttingen, Germany.
L
L
Rappold
Department of Cardiology and Pulmonology, Heart Center, University of Göttingen, Germany; Department of Paediatric Cardiology, Heart Center, University of Göttingen, Germany.
C
C
Dellas
Department of Cardiology and Pulmonology, Heart Center, University of Göttingen, Germany.
G
G
Hasenfuß
Department of Thrombosis and Hemostasis, Leiden University Medical Center, Leiden, the Netherlands.
M V
MV
Huisman
Center for Thrombosis and Hemostasis (CTH), University Medical Center Mainz, Germany.
S
S
Konstantinides
Center for Thrombosis and Hemostasis (CTH), University Medical Center Mainz, Germany; Department of Cardiology and Pulmonology, Heart Center, University of Göttingen, Germany. Electronic address: mareike.lankeit@unimedizin-mainz.de.
M
M
Lankeit
D000328:Adult; D000368:Aged; D000465:Algorithms; D002908:Chronic Disease; D015331:Cohort Studies; D020000:Decision Support Systems, Clinical; D003936:Diagnosis, Computer-Assisted; D004452:Echocardiography; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000150:complications*; D008297:Male; D008403:Mass Screening; D008875:Middle Aged; D020097:Natriuretic Peptide, Brain / Q000737:chemistry; D010446:Peptide Fragments / Q000737:chemistry; D011655:Pulmonary Embolism / Q000150:complications* / Q000175:diagnosis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013923:Thromboembolism / Q000150:complications* / Q000175:diagnosis*; D020107:Troponin T / Q000737:chemistry
D010446:Peptide Fragments; D020107:Troponin T; C109794:pro-brain natriuretic peptide (1-76); D020097:Natriuretic Peptide, Brain
ECG; Echocardiography; NT-proBNP; Pulmonary embolism; Pulmonary hypertension; Screening