https://doi.org/10.1007/s00392-024-02526-y
1Justus-Liebig-Universität Gießen, Campus Kerckhoff Bad Nauheim, Deutschland; 2Kerckhoff-Klinik GmbH Thoraxchirurgie Bad Nauheim, Deutschland; 3Universitätsklinikum Frankfurt Med. Klinik III - Kardiologie, Angiologie Frankfurt am Main, Deutschland; 4Universitätsklinikum Gießen und Marburg GmbH Medizinische Klinik II - Pneumologie Gießen, Deutschland; 5Kerckhoff Klinik GmbH Allgemeine Pneumologie Bad Nauheim, Deutschland; 6Asklepios Neurologische Klinik Bad Salzhausen, Deutschland
Background:
Chronic thromboembolic pulmonary hypertension (CTEPH) is considered to be a late sequela of pulmonary embolism (PE) causing distressing symptoms, a reduced quality of life and an increased mortality rate. CTEPH may be accompanied by typical electrocardiographic (ECG) changes which may help in diagnosis. Less than one quarter of patients who develop CTEPH are diagnosed in Germany. The aim of the present study was to explore the utility of a simple ECG model for an improved detection of CTEPH after PE.
Methods:
The present study was conducted as a bicentric, retrospective study in two German high volume referral centres for pulmonary hypertension (PH). Between 07/2012 and 11/2023, 100 patients without PH and 200 patients with PH, all confirmed by right heart catheterisation (RHC), were retrospectively enrolled. Sensitivity and specificity of ECG parameters for the diagnosis of PH were calculated. Based on the results a simple ECG model for the detection of CTEPH was developed and its potential utility in CTEPH screening after PE calculated.
Results:
A total of 300 patients, subdivided into the control (n = 100) and PH group (n = 200, 100 with pulmonary arterial hypertension and 100 with CTEPH), were included. The parameter “R V1, V2 + S I, aVL - S V1” with a cut-off of > -0.25 mV was determined the best parameter for application as a screening test (sensitivity: 90%, specificity: 53%). An ECG score based on 5 electrocardiographic parameters (≥ one of the following positive: QRS axis associated with right heart strain, P dextroatriale or P biatriale, R/S in V1 > 1.0, “R V1, V2 + S I, aVL - S V1” > 0.6 mV, “R V1 + S V5, V6” > 1.05 mV) was determined best for application as a confirmatory test (specificity : 90%, sensitivity: 81%). When applying this diagnostic ECG model to the present PH cohort, 73% of PH patients were correctly identified and only 5% of non-PH patients were incorrectly identified as PH patients. About 2% of PE survivors develop CTEPH, but only about 400 CTEPH cases are diagnosed annually (detection rate: 24%). When theoretically applying the present diagnostic ECG model in screening of persistently symptomatic PE survivors after PE (Figure 1), based on German figures a total 69% of CTEPH patients could be detected and unnecessary RHC would only be performed on 1.5% of non-CTEPH patients. Compared to the current estimated CTEPH detection rate this would be an increase of 295% (from 24% to 69%).
Conclusions:
Electrocardiographic screening of all persistently symptomatic PE survivors could potentially increase the CTEPH detection rate from about 24% to 69%, with a rate of only about 1.5% unnecessary RHCs, if all persistently symptomatic PE survivors were given an ECG as standard follow-up. However, this approach remains theoretical and needs to be validated externally.
Figure 1 Potential effectiveness of an ECG derived diagnostic model for the detection of chronic thromboembolic pulmonary hypertension based on German figures